WO1999062934A9 - Interferon receptor hkaef92 - Google Patents

Abstract

The present invention relates to a novel Interferon receptor 'INFR-HKAEF92' protein which is a member of the Interferon/IL-10 receptor family. In particular, isolated nucleic acid molecules are provided encoding the human INFR-HKAEF92 protein. INFR-HKAEF92 polypeptides are also provided as are vectors, host cells and recombinant methods for producing the same. The invention further relates to screening methods for identifying agonists and antagonists of INFR-HKAEF92 activity. Also provided are diagnostic methods for detecting immune system-related disorders and therapeutic methods for treating immune system-related disorders.

Description

Interferon Receptor HKNEF92

Field of the Invention

The present invention relates to a novel human gene encoding a polypeptide which is a member of the interferon receptor family. More specifically, isolated nucleic acid molecules are provided encoding a human polypeptide named Interferon Receptor HKAEF92, hereinafter referred to as "LΝFR-HKAEF92". LNFR-HKAEF92 polypeptides are also provided, as are vectors, host cells and recombinant methods for producing the same. Also provided are diagnostic methods for detecting disorders related to the immune system, and therapeutic methods for treating such disorders. The invention further relates to screening methods for identifying agonists and antagonists of INFR-HKAEF92 activity.

Background of the Invention Interferons (IFNs) are a well known family of cytokines secreted by a large variety of eukaryotic cells upon exposure to various stimuli. The interferons have been classified by their chemical and biological characteristics into four groups: IFN-alpha (leukocytes), LFN-beta (fibroblasts), IFN-gamma (lymphocytes), and IFN-omega (leukocytes). LFN-alpha and beta are known as Type I interferons; IFN-gamma is known as a Type-II or immune interferon. A single functional gene in the human genome codes for interferon omega (IFN omega), a monomeric glycoprotein distantly related in structure to LFN-alpha and LFN-beta, but unrelated to IFN-gamma. IFN-omega is secreted by virus-infected leukocytes as a major component of human leukocyte interferon. The LFNs exhibit anti-viral, immunoregulatory, and antiproliferative activity. The clinical potential of interferons has been recognized, and will be summarized below.

Anti-viral: LFNs have been used clinically for anti-viral therapy, for example, in the treatment of AIDS (Lane. Semin. Oncol. 18:46-52 (Oct. 1991)), viral hepatitis including chronic hepatitis B. hepatitis C (Woo, M. H. and Brunakis, T. G., Ann. Parmacother, 31:330-337 (March 1997); Gibas, A.L., Gastroenterologist, 1:129-142 (June 1993)), hepatitis D. papilloma viruses (Levine, L.A. et al, Urology 47:55-3-557 (April 1996)), herpes (Ho, M., Annu. Rev. Med. 38:51-59 (1987)), viral encephalitis (Wintergerst et al, Infection, 20:207-212 (July 1992)), and in the prophylaxis of rhinitis and respiratory infections (Ho. M., Annu. Rev. Med. 38:51-59 (1987)).

Anti-parasitic: LFNs have been suggested for anti-parasite therapy, for example, IFN-gamma for treating Cryptosporidium parvum infection (Rehg, J.E., J. Infect Des. 174:229-232 (July 1996)).

Anti-bacterial: LFNs have been used clinically for anti-bacterial therapy. For example, IFN-gamma has been used in the treatment of multidrug-resistant pulmonary tuberculosis (Condos. R. et al, Lancet 349: 1513-1515 ( 1997)).

Anti-cancer: Interferon therapy has been used in the treatment of numerous cancers (e.g., hairy cell leukemia (Hofmann et al, Cancer Treat. Rev. 12 (Suppl. B):33-37 (Dec. 1985)), acute myeloid leukemia (Stone, R.M. et al. Am. J. Clin. Oncol. 16:159-163 (April 1993)), osteosarcoma (Strander, H. et al, Acta Oncol.

34:877-880 (1995)), basal cell carcinoma (Dogan, B. et al, Cancer Lett. 91:215-219 (May 1995)), glioma (Fetell, M.R. et al, Cancer 65: 78-83 (Jan. 1990)), renal cell carcinoma (Aso, Y. et al. Prog. Clin. Biol. Res. 303:653-659 (1989)), multiple myeloma (Peest, D. et al, Br. J. Haematol. 94:425-432 (Sept. 1996)), melanoma (Ikic, D. et al, Int. J Dermatol. 34:872-874 (Dec. 1995)), and Hodgkin's disease (Rybak, M.E. et al., 7 Biol. Response Mod. 9: 1-4 (Feb. 1990)). Synergistic treatment of advanced cancer with a combination of alpha interferon and temozolomide has also been reported (Patent publication WO 9712630 to Dugan, M.H.).

Immunotherapy: IFNs have been used clinically for immunotherapy or more particularly, (1) for example, to prevent graft vs. host rejection, or to curtail the progression of autoimmune diseases, such as arthritis, multiple sclerosis, (2) or diabetes (3). LFN-beta is approved of sale in the United States for the treatment (i.e., as an immunosuppressant) of multiple sclerosis. Recently it has been reported that patients with multiple sclerosis have diminished production of type I interferons and interleukin-2 (Wandinger, K.P. et al., J. Neurol. Sci. 149: 87-93( 1997)). In addition, immunotherapy with recombinant LFN-alpha (in combination with recombinant human LL-2) has been used successfully in lymphoma patients following autologous bone marrow or blood stem cell transplantation, that may intensify remission following translation (Nagler, A. et al, Blood 89:3951-3959 (June 1997)).

Anti-allergy: The administration of LFN-gamma has been used in the treatment of allergies in mammals (See, Patent Pubhcation WO 8701288 to Parkin, J.M. and Pinchina, A.J . It has also recently been demonstrated that there is a reduced production of LL-12 and LL- 12-dependent LFN-gamma release in patients with allergic asthma (van der Pouw Kraan, T.C. et al.. J. Immunol. 158:5560-5565 (1997)). Thus, IFN may be useful in the treatment of allergy by inhibiting the humoral response.

Vaccine adjuvantation: Interferons may be used as an adjuvant or coadjuvant to enhance or simulate the immune response in cases of prophylactic or therapeutic vaccination (Heath. A.W. and Playfair, J.H.L., Vaccine 10:427-434 (1992)). A receptor is a protein which is embedded in the membrane of a cell and provides the cell with one mechanism of responding to its environment. An extracellular portion of the receptor can recognize and bind to ligands in the extracellular environment. These interactions are specific in nature. A receptor will recognize only one, or a few ligands. A receptor which binds to one or more interferon ligands is an interferon receptor. Thus, in order for an interferon ligand to directly affect any particular cell, the cell must display and interferon receptor on its surface.

Thus, there is a need for the isolation and characterization of interferon receptor polypeptides that modulate immunoregulatory and antiproliferative activities and can play a role in detecting, preventing, ameliorating or correcting disorders associated with viral infection, immune dysfunction and proliferative diseases such as cancer.

Summary of the Invention The present invention relates to novel polynucleotides and the encoded polypeptides LNFR-HKAET92. Moreover, the present invention relates to vectors, host cells, antibodies, and recombinant methods for producing the polypeptides and polynucleotides. Also provided are diagnostic methods for detecting disorders related to the polypeptides, and therapeutic methods for treating such disorders. The invention further relates to screening methods for identifying binding partners of INFR-HKAET92.

Brief Description of the Figures Figure 1 shows the nucleotide sequence (SEQ ID NO: 1) and deduced amino acid sequence (SEQ ID NO:2) of LNFR-HKAEF92. The predicted leader sequence of about 29 amino acid residues (residues 1-29) is underlined as is the predicted transmembrane domain of about 17 amino acid residues (residues 234-250).

Figure 2 shows the regions of identity between the amino acid sequences of the LNFR-HKAEF92 protein and translation products of other interferon receptor polypeptides: INFRA1 (SEQ ID NO:3); LNFAR2 (SEQ ID NO:4): INFrRalpha (SEQ ID NO:5); INFgR AF- 1 (SEQ ID NO:6); LL10R1 (SEQ ID NO:7); LL10R2/CRFB4 (SEQ ID NO:8); and CRF2-4 (SEQ ID NO:9), determined by the computer routine Megalign in the DNAStar suite. Figure 3 shows an analysis of the INFR-HKAEF92 amino acid sequence.

Alpha, beta, turn and coil regions; hydrophilicity and hydrophobicity; amphipathic regions; flexible regions; antigenic index and surface probability are shown. In the " Antigenic Index - Jameson-Wolf graph, the positive peaks indicate locations of the highly antigenic regions of the LNFR-HKAEF92 protein, i.e., regions from which epitope-bearing peptides of the invention can be obtained.

Figure 4 shows the nucleic acid sequences HTECC41R (SEQ ID NO: 10) and HKAAF94R (SEQ ID NO: 11 ), both of which are related to SEQ ID NO: 1.

Detailed Description The present invention provides isolated nucleic acid molecules comprising a polynucleotide encoding an LNFR-HKAEF92 polypeptide having the amino acid sequence shown in SEQ LD NO:2, which was determined by sequencing a cloned cDNA. The nucleotide sequence shown in Figure 1 (SEQ ID NO: 1) was obtained by sequencing the HKAEF92 clone, which was deposited on April 7, 1998 at the American Type Culture Collection. 12301 Park Lawn Drive, Rockville, Maryland

20852, and given accession number ATCC 209746. The deposited clone is contained in the pCMVSport 2.0 plasmid (Life Technologies. Inc.. Gaithersburg, MD).

The LNFR-HKAEF92 protein of the present invention shares sequence similarity with several interferon (INF) receptors as shown in (Figure 2). Based on the structural similarity between these molecules LNFR-HKAEF92 is expected to share certain biological activities with members of the LNFR polypeptide family as described in detail below.

Nucleic Acid Molecules

Unless otherwise indicated, all nucleotide sequences determined by sequencing a DNA molecule herein were determined using an automated DNA sequencer (such as the Model 373 from Applied Biosystems, Inc., Foster City, CA), and all amino acid sequences of polypeptides encoded by DNA molecules determined herein were predicted by translation of a DNA sequence determined as above. Therefore, as is known in the art for any DNA sequence determined by this automated approach, any nucleotide sequence determined herein may contain some errors. Nucleotide sequences determined by automation are typically at least about 90% identical, more typically at least about 95% to at least about 99.9% identical to the actual nucleotide sequence of the sequenced DNA molecule. The actual sequence can be more precisely determined by other approaches including manual DNA sequencing methods well known in the art. As is also known in the art, a single insertion or deletion in a determined nucleotide sequence compared to the actual sequence will cause a frame shift in translation of the nucleotide sequence such that the predicted amino acid sequence encoded by a determined nucleotide sequence will be completely different from the amino acid sequence actually encoded by the sequenced DNA molecule, beginning at the point of such an insertion or deletion.

By "nucleotide sequence" of a nucleic acid molecule or polynucleotide is intended, for a DNA molecule or polynucleotide, a sequence of deoxyribonucleotides, and for an RNA molecule or polynucleotide, the corresponding sequence of ribonucleotides (A, G, C and U), where each thymidine deoxyribonucleotide (T) in the specified deoxyribonucleotide sequence is replaced by the ribonucleotide uridine (U).

Using the information provided herein, such as the nucleotide sequence in Figure 1 (SEQ ID NO: 1), a nucleic acid molecule of the present invention encoding an LNFR-HKAEF92 polypeptide may be obtained using standard cloning and screening procedures, such as those for cloning cDNAs using mRNA as starting material. Illustrative of the invention, the nucleic acid molecule described in Figure 1 (SEQ ID NO: 1) was discovered in a cDNA library derived from human keratinocytes.

While this gene appears to be primarily expressed in keratinocytes additional clones of the same gene were also identified in cDNA libraries from the following tissues: a healing wound, testes and smooth muscle.

The determined nucleotide sequence of the INFR-HKAEF92 cDNA of Figure 1 (SEQ ID NO: 1) contains an open reading frame encoding a protein of 311 amino acid residues, with an initiation codon at nucleotide positions 130-132 of the nucleotide sequence in Figure 1 (SEQ ID NO: 1). The open reading frame of the LNFR-HKAEF92 gene includes the following conserved domains: (a) a predicted extracellular domain of about 204 amino acid residues (shown as residues 130-233 in Figure 1); (b) a predicted transmembrane domain of about 17 amino acid residues (shown as residues 234-250 in Figure 1), and (c) an intracellular domain of about 61 amino acid residues (shown as residues 251-311 in Figure 1).

As one of ordinary skill would appreciate, due to the possibilities of sequencing errors discussed above, the actual complete LNFR-HKAEF92 polypeptide encoded by the deposited cDNA may be somewhat longer or shorter than shown in Figure 1. More generally, the actual open reading frame may be anywhere in the range of ± 40 amino acids, more likely in the range of ± 10 amino acids, of that predicted from the methionine codon at the N-terminus shown in Figure 1 (SEQ ID NO: 1). It will further be appreciated that, depending on the analytical criteria used for identifying various functional domains, the exact "address" of the domains of the INFR-HKAEF92 polypeptide may differ slightly from the predicted positions above. For example, the exact location of the LNFRHKAEF92 extracellular domain in SEQ ID NO:2 may vary slightly (e.g., the address may "shift" by about 1 to about 20 residues, more likely about 1 to about 5 residues) depending on the criteria used to define the domain. In this case, the ends of the transmembrane domain and the beginning of the extracellular domain were predicted on the basis of the identification of the hydrophobic amino acid sequence in the above indicated positions, as shown in Figure 3. In any event, as discussed further below, the invention further provides polypeptides having various residues deleted from the N-terminus of the complete polypeptide. including polypeptides lacking one or more amino acids from the N-terminus of the extracellular domain described herein, which constitute soluble forms of the extracellular domain of the INFR-HKAEF92 protein.

Leader and Mature Sequences The amino acid sequence of the complete LNFR-HKAEF92 protein includes a leader sequence and a mature protein, as shown in SEQ ID NO:2. More in particular, the present invention provides nucleic acid molecules encoding a mature form of the INFR-HKAEF92 protein. Thus, according to the signal hypothesis, once export of the growing protein chain across the rough endoplasmic reticulum has been initiated, proteins secreted by mammalian cells have a signal or secretory leader sequence which is cleaved from the complete polypeptide to produce a secreted "mature" form of the protein. Most mammalian cells and even insect cells cleave secreted proteins with the same specificity. However, in some cases, cleavage of a secreted protein is not entirely uniform, which results in two or more mature species of the protein. Further, it has long been known that the cleavage specificity of a secreted protein is ultimately determined by the primary structure of the complete protein, that is, it is inherent in the amino acid sequence of the polypeptide. Therefore, the present invention provides a nucleotide sequence encoding the mature LNFR-HKAEF92 polypeptide having the amino acid sequence encoded by the cDNA clone identified as ATCC Deposit No. 209746. By the "mature

LNFR-HKAEF92 polypeptide having the amino acid sequence encoded by the cDNA clone in ATCC Deposit No. 209746" is meant the mature form(s) of the INFR-HKAEF92 protein produced by expression in a mammalian cell (e.g., COS cells, as described below) of the complete open reading frame encoded by the human DNA sequence of the corresponding clone contained in the vector in the deposit.

In addition, methods for predicting whether a protein has a secretory leader as well as the cleavage point for that leader sequence are available. For instance, the method of McGeoch (Virus Res. 3:271-286 (1985)) uses the information from a short N-terminal charged region and a subsequent uncharged region of the complete (uncleaved) protein. The method of von Heinje (Nucleic Acids Res. 14:4683-4690 (1986)) uses the information from the residues surrounding the cleavage site, typically residues -13 to +2 where +1 indicates the amino terminus of the mature protein. The accuracy of predicting the cleavage points of known mammalian secretory proteins for each of these methods is in the range of 75-80% (von Heinje, supra). However, the two methods do not always produce the same predicted cleavage point(s) for a given protein.

In the present case, the deduced amino acid sequence of the complete LNFR-HKAEF92 polypeptide was analyzed by a computer program "PSORT" available from Dr. Kenta Nakai of the Institute for Chemical Research, Kyoto

University (see K. Nakai and M. Kanehisa, Genomics 14:897-911 (1992)), which is an expert system for predicting the cellular location of a protein based on the amino acid sequence. As part of this computational prediction of localization, the methods of McGeoch and von Heinje are incorporated. The analysis of the LNFR-HKAEF92 amino acid sequence by this program predicted a cleavage site between residues 29 and 30 shown in Figure 1 such that the leader sequence is 29 amino acids long and the mature LNFR-HKAEF92 polypeptide begins at residue 30.

As one of ordinary skill would appreciate from the above discussions, due to the possibilities of sequencing errors as well as the variability of cleavage sites in different known proteins, the mature LNFR-HKAEF92 polypeptide encoded by the deposited cDNA is expected to consist of about 282 amino acids (presumably residues 30 to 311 of Figure 1 (SEQ ID NO:2), but may consist of any number of amino acids in the range of about 272 to 292 amino acids: and the actual leader sequence(s) of this protein is expected to be 29 amino acids, but may consist of any number of amino acids in the range of 19 to 39 amino acids; i.e., the mature polypeptide is expected to consist of residues 30-31 1 but may actually consist of one (or more) of the following polypeptides, 19-311, 20-311. 21-311, 22-311, 23 -311, 24-311, 25-311, 26-311, 27-311. 28 -311, 29-311, 30-311. 31-311, 32-311, 33-311, 34-311, 35-311, 36-311, 37-311, 38-311 and/or 39-31 1. Polynucleotides encoding such polypeptides are also provided.

As indicated, nucleic acid molecules of the present invention may be in the form of RNA, such as mRNA, or in the form of DNA. including, for instance, cDNA and genomic DNA obtained by cloning or produced synthetically. The DNA may be double-stranded or single-stranded. Single-stranded DNA or RNA may be the coding strand, also known as the sense strand, or it may be the non-coding strand, also referred to as the anti-sense strand.

By "isolated" nucleic acid molecule(s) is intended a nucleic acid molecule, DNA or RNA, which has been removed from its native environment. For example, recombinant DNA molecules contained in a vector are considered isolated for the purposes of the present invention. Further examples of isolated DNA molecules include recombinant DNA molecules maintained in heterologous host cells or purified (partially or substantially) DNA molecules in solution. Isolated RNA molecules include in vivo or in vitro RNA transcripts of the DNA molecules of the present invention. Isolated nucleic acid molecules according to the present invention further include such molecules produced synthetically.

Isolated nucleic acid molecules of the present invention include DNA molecules comprising an open reading frame (ORF) with an initiation codon at positions 130-132 of the nucleotide sequence shown in Figure 1 (SEQ ID NO: 1). In addition, isolated nucleic acid molecules of the invention include DNA molecules which comprise a sequence substantially different from those described above but which, due to the degeneracy of the genetic code, still encode the LNFR- HKAEF92 protein. Of course, the genetic code and species-specific codon preferences are well known in the art. Thus, it would be routine for one skilled in the art to generate the degenerate variants described above, for instance, to optimize codon expression for a particular host (e.g., change codons in the human mRNA to those preferred by a bacterial host such as E. coli).

In another aspect, the invention provides isolated nucleic acid molecules encoding the LNFR-HKAEF92 polypeptide having an amino acid sequence encoded by the HKAEF92 cDNA clone contained in the plasmid deposited as ATCC Deposit No. 209746 on April 7. 1998. Preferably, this nucleic acid molecule will encode the mature polypeptide encoded by the above-described deposited cDNA clone.

The invention further provides an isolated nucleic acid molecule having the nucleotide sequence shown in Figure 1 (SEQ ID NO:l) or the nucleotide sequence of the LNFR-HKAEF92 cDNA contained in the above-described deposited clone, or a nucleic acid molecule having a sequence complementary to one of the above sequences. Such isolated molecules, particularly DNA molecules, are useful as probes for gene mapping, by in situ hybridization with chromosomes, and for detecting expression of the LNFR-HKAEF92 gene in human tissue, for instance, by Northern blot analysis.

The present invention is further directed to nucleic acid molecules encoding portions of the nucleotide sequences described herein as well as to fragments of the isolated nucleic acid molecules described herein. In particular, the invention provides a polynucleotide having a nucleotide sequence representing the portion of SEQ ID NO: l which consists of positions 130-1062 of SEQ ID NO: 1.

In addition, the invention provides nucleic acid molecules having nucleotide sequences related to extensive portions of SEQ ID NO: 1 which have been determined from the following related cDNA clones: sequence HTECC41R (SEQ ID NO: 10) was determined from cDNA clone HTECC41 and sequence HKAAF94R (SEQ ID NO: 11) was determined from cDNA clone HKAAF94. These sequences are shown in Figure 4.

Further, the invention includes a polynucleotide comprising any portion of at least about 30 nucleotides. preferably at least about 50 nucleotides, of SEQ ID NO: 1 from nucleotide 132 to 1062 (or preferably from nucleotide 200 to 750).

More generally, by a fragment of an isolated nucleic acid molecule having the nucleotide sequence of the deposited cDNA or the nucleotide sequence shown in Figure 1 (SEQ ID NO: 1), preferably within the coding region (nucleotides 132- 1062), more preferably nucleotides 200 to 750. is intended fragments at least about 15 nt, and more preferably at least about 20 nt, still more preferably at least about 30 nt, and even more preferably, at least about 40 nt in length which are useful as diagnostic probes and primers as discussed herein. Of course, larger fragments 50-300 nt in length are also useful according to the present invention as are fragments corresponding to most, if not all. of the nucleotide sequence of the deposited cDNA or as shown in Figure 1 (SEQ ID NO: 1). By a fragment at least 20 nt in length, for example, is intended fragments which include 20 or more contiguous bases from the nucleotide sequence of the deposited cDNA or the nucleotide sequence as shown in Figure 1 (SEQ ID NO: 1). Preferred nucleic acid fragments of the present invention include nucleic acid molecules encoding epitope-bearing portions of the LNFR-HKAEF92 polypeptide as identified in Figure 3 and described in more detail below.

In another aspect, the invention provides an isolated nucleic acid molecule comprising a polynucleotide which hybridizes under stringent hybridization conditions to a portion of the polynucleotide in a nucleic acid molecule of the invention described above, for instance, the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746. By "stringent hybridization conditions" is intended overnight incubation at 42° C in a solution comprising: 50% formamide. 5x SSC (150 mM NaCl, 15 mM trisodium citrate), 50 mM sodium phosphate (pH 7.6), 5x Denhardt's solution, 10% dextran sulfate. and 20 μg/ml denatured, sheared salmon sperm DNA, followed by washing the filters in 0.1 x SSC at about 65° C.

By a polynucleotide which hybridizes to a "portion" of a polynucleotide is intended a polynucleotide (either DNA or RNA) hybridizing to at least about 15 nucleotides (nt), and more preferably at least about 20 nt, still more preferably at least about 30 nt, and even more preferably about 30-70 (e.g., 50) nt of the reference polynucleotide. These are useful as diagnostic probes and primers as discussed above and in more detail below.

By a portion of a polynucleotide of "at least 20 nt in length," for example, is intended 20 or more contiguous nucleotides from the nucleotide sequence of the reference polynucleotide (e.g., the deposited cDNA or the nucleotide sequence as shown in Figure 1 (SEQ ID NO: 1)). Of course, a polynucleotide which hybridizes only to a poly A sequence (such as the 3' terminal poly(A) tract of the LNFR-HKAEF92 cDNA shown in Figure 1 (SEQ ID NO: 1)), or to a complementary stretch of T (or U) residues, would not be included in a polynucleotide of the invention used to hybridize to a portion of a nucleic acid of the invention, since such a polynucleotide would hybridize to any nucleic-acid molecule containing a poly (A) stretch or the complement thereof (e.g., practically any double-stranded cDNA clone). As indicated, nucleic acid molecules of the present invention which encode a

LNFR-HKAEF92 polypeptide may include, but are not limited to those encoding the amino acid sequence of the mature polypeptide. by itself; and the coding sequence for the mature polypeptide and additional sequences, such as those encoding the about 29 amino acid leader or secretory sequence, such as a pre-, or pro- or prepro-protein sequence: the coding sequence of the mature polypeptide, with or without the aforementioned additional coding sequences.

Also encoded by nucleic acids of the invention are the above protein sequences together with additional, non-coding, sequences, including for example, but not limited to introns and non-coding 5' and 3' sequences, such as the transcribed, non-translated sequences that play a role in transcription, mRNA processing, including splicing and polyadenylation signals, for example - ribosome binding and stability of mRNA; an additional coding sequence which codes for additional amino acids, such as those which provide additional functionalities. Thus, the sequence encoding the polypeptide may be fused to a marker sequence, such as a sequence encoding a peptide which facilitates purification of the fused polypeptide. In certain preferred embodiments of this aspect of the invention, the marker amino acid sequence is a hexa-histidine peptide. such as the tag provided in a pQE vector (QIAGEN, Inc., 9259 Eton Avenue. Chatsworth, CA, 91311), among others, many of which are commercially available. As described in Gentz et al, Proc. Natl. Acad. Sci. USA 86:821-824 (1989), for instance, hexa-histidine provides for convenient purification of the fusion protein. The "HA" tag is another peptide useful for purification which corresponds to an epitope derived from the influenza hemagglutinin protein, which has been described by Wilson et al, Cell 37:161

(1984). As discussed below, other such fusion proteins include the INFR-HKAEF92 fused to Fc at the N- or C-terminus.

Variant and Mutant Polynucleotides The present invention further relates to variants of the nucleic acid molecules of the present invention, which encode portions, analogs or derivatives of the LNFR-HKAEF92 protein. Variants may occur naturally, such as a natural allelic variant. By an "allelic variant" is intended one of several alternate forms of a gene occupying a given locus on a chromosome of an organism. Genes II, Lewin, B., ed., John Wiley & Sons, New York (1985). Non-naturally occurring variants may be produced using art-known mutagenesis techniques.

Such variants include those produced by nucleotide substitutions, deletions or additions. The substitutions, deletions or additions may involve one or more nucleotides. The variants may be altered in coding regions, non-coding regions, or both. Alterations in the coding regions may produce conservative or non-conservative amino acid substitutions, deletions or additions. Especially preferred among these are silent substitutions, additions and deletions, which do not alter the properties and activities of the LNFR-HKAEF92 protein or portions thereof. Also especially preferred in this regard are conservative substitutions. Most highly preferred are nucleic acid molecules encoding the mature protein having the amino acid sequence shown in SEQ ID NO: 2 or the mature INFR-HKAEF92 amino acid sequence encoded by the deposited HKAEF92 cDNA clone. Most highly preferred are nucleic acid molecules encoding the extracellular domain of the protein having the amino acid sequence shown in SEQ ID NO:2 or the extracellular domain of the INFR-HKAEF92 amino acid sequence encoded by the deposited HKAEF92 cDNA clone. Further embodiments include an isolated nucleic acid molecule comprising a polynucleotide having a nucleotide sequence at least 90% identical, and more preferably at least 95%, 96%, 97%, 98% or 99% identical to a polynucleotide selected from the group consisting of: (a) a nucleotide sequence encoding the complete amino acid sequence in SEQ ID NO:2; (b) a nucleotide sequence encoding positions 2 to 311 of SEQ ID NO:2; (c) a nucleotide sequence encoding the amino acid sequence at positions 30 to 311 of SEQ ID NO:2: (d) a nucleotide sequence encoding the amino acid sequence at positions 30 to 233 in SEQ ID NO:2 (e) a nucleotide sequence encoding a polypeptide having the complete amino acid sequence encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746; (f) a nucleotide sequence encoding the polypeptide having the complete amino acid sequence excepting the N-terminal methionine encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746; (g) a nucleotide sequence encoding the mature polypeptide having the amino acid sequence encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746; (h) a nucleotide sequence encoding the extracellular domain of the polypepide encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746; and (i) a nucleotide sequence complementary to any of the nucleotide sequences in (a), (b), (c), (d), (e), (f), (g) or (h) above.

Further embodiments of the invention include isolated nucleic acid molecules that comprise a polynucleotide having a nucleotide sequence at least 90% identical, and more preferably at least 95%, 96%, 97%, 98% or 99% identical, to any of the nucleotide sequences in (a), (b), (c), (d), (e), (f), (g), (h) or (i) above, or a polynucleotide which hybridizes under stringent hybridization conditions to a polynucleotide in (a), (b), (c), (d), (e), (f), (g), (h) or (i), above. This polynucleotide which hybridizes does not hybridize under stringent hybridization conditions to a polynucleotide having a nucleotide sequence consisting of only A residues or of only T residues. An additional nucleic acid embodiment of the invention relates to an isolated nucleic acid molecule comprising a polynucleotide which encodes the amino acid sequence of an epitope-beaπng portion of a INFR HKAEF92 polypeptide having an amino acid sequence in (a), (b). (c). (d). (e). (f). (g) or (h), above

The present imention also relates to recombinant vectors, which include the isolated nucleic acid molecules of the present invention, and to host cells containing the recombinant vectors, as well as to methods of making such vectors and host cells and for using them for production of INFR-HKAEF92 polypeptides or peptides by recombinant techniques

By a polynucleotide having a nucleotide sequence at least, for example, 95% "identical" to a reference nucleotide sequence encoding an INFR HKAEF92 polypeptide is intended that the nucleotide sequence of the polynucleotide is identical to the reference sequence except that the polynucleotide sequence may include up to five point mutations per each 100 nucleotides of the reference nucleotide sequence encoding the INFR-HKAEF92 polypeptide In other words, to obtain a polynucleotide having a nucleotide sequence at least 95% identical to a reference nucleotide sequence, up to 5% of the nucleotides in the reference sequence may be deleted, inserted or substituted with another nucleotide These mutations of the reference sequence may occur at the 5' or 3' terminal positions of the reference nucleotide sequence or anywhere between those terminal positions, interspersed either individually among nucleotides in the reference sequence or in one or more contiguous groups within the reference sequence

As a practical matter, whether any particular nucleic acid molecule is at least 90%, 95%, 96%. 97% 98% or 99% identical to, for instance, the nucleotide sequence shown in Figure 1 or to the nucleotides sequence of the deposited cDNA clone can be determined conventionally using known computer programs such as the Bestfit program (Wisconsin Sequence Analysis Package, Version 8 for Unix, Genetics Computer Group. University Research Park, 575 Science Drive. Madison, Wl 5371 1) Bestfit uses the local homology algorithm of Smith and Waterman, Advances in Applied Mathematics 2 482-489 ( 1981), to find the best segment of homology between two sequences When using Bestfit or any other sequence alignment program to determine whether a particular sequence is, for instance, 95% identical to a reference sequence according to the present invention, the parameters are set, of course, such that the percentage of identity is calculated over the full length of the reference nucleotide sequence and that gaps in homology of up to 5% of the total number of nucleotides in the reference sequence are allowed The present application is directed to nucleic acid molecules at least 90%, 95%, 96%, 97%, 98% or 99% identical to the nucleic acid sequence shown in Figure 1 (SEQ ID NO: 1) or to the nucleic acid sequence of the deposited cDNA, irrespective of whether they encode a polypeptide having LNFR-HKAEF92 activity. This is because even where a particular nucleic acid molecule does not encode a polypeptide having INFR-HKAEF92 activity, one of skill in the art would still know how to use the nucleic acid molecule, for instance, as a hybridization probe or a polymerase chain reaction (PCR) primer. Uses of the nucleic acid molecules of the present invention that do not encode a polypeptide having LNFR-HKAEF92 activity include, inter alia, (1) isolating the LNFR HKAEF92 gene or allelic variants thereof in a cDNA library; (2) in situ hybridization (e.g., "FISH") to metaphase chromosomal spreads to provide precise chromosomal location of the LNFR-HKAEF92 gene, as described in Verma et al., Human Chromosomes: A Manual of Basic Techniques, Pergamon Press, New York (1988); and Northern Blot analysis for detecting LNFR-HKAEF92 mRNA expression in specific tissues.

Preferred, however, are nucleic acid molecules having, sequences at least 90%, 95%, 96%, 97%, 98% or 99% identical to the nucleic acid sequence shown in Figure 1 (SEQ ID NO: 1) or to the nucleic acid sequence of the deposited cDNA clone HKAEF92 which do, in fact, encode a polypeptide having LNFR-HKAEF92 protein activity. By "a polypeptide having INFR-HKAEF92 activity" is intended polypeptides exhibiting activity similar, but not necessarily identical, to an activity of the soluble extracellular form of the LNFR-HKAEF92 protein of the invention, as measured in a particular biological assay. For example, the LNFRHKAEF92 protein of the present invention is expected to activate Jaks according to the method of Example 12.

LNFR-HKAEF92 protein activates Jaks in a dose-dependent manner in the above-described assay. Thus, "a polypeptide having LNFR-HKAEF92 protein activity" includes polypeptides that also exhibit any of the same activities in the above-described assays in a dose-dependent manner. Although the degree of dose- dependent activity need not be identical to that of the NFR-HKAEF92 protein, preferably, "a polypeptide having LNFR-HKAEF92 protein activity" will exhibit substantially similar dose-dependence in a given activity as compared to the LNFR-HKAEF92 protein (i.e., the candidate polypeptide will exhibit greater activity or not more than about 25-fold less and, preferably, not more than about tenfold less activity relative to the reference LNFR-HKNEF92 protein).

Of course, due to the degeneracy of the genetic code, one of ordinary skill in the art will immediately recogmze that a large number of the nucleic acid molecules having a sequence at least 90%, 95%, 96%, 97%, 98%, or 99% identical to the nucleic acid sequence of the deposited cDΝA or the nucleic acid sequence shown in Figure 1 (SEQ ID NO: 1) will encode a polypeptide "having INFR-HKAEF92 protein activity." In fact, since degenerate variants of these nucleotide sequences all encode the same polypeptide, this will be clear to the skilled artisan even without performing the above described comparison assay. It will be further recognized in the art that, for such nucleic acid molecules that are not degenerate variants, a reasonable number will also encode a polypeptide having LNFR-HKAEF92 protein activity. This is because the skilled artisan is fully aware of amino acid substitutions that are either less likely or not likely to significantly effect protein function (e.g., replacing one aliphatic amino acid with a second aliphatic amino acid), as further described below.

Vectors and Host Cells

The present invention also relates to vectors which include the isolated DNA molecules of the present invention, host cells which are genetically engineered with the recombinant vectors, and the production of LNFR-HKAEF92 polypeptides or fragments thereof by recombinant techniques. The vector may be, for example, a phage, plasmid, viral or retroviral vector. Retroviral vectors may be replication competent or replication defective. In the latter case, viral propagation generally will occur only in complementing host cells.

The polynucleotides may be joined to a vector containing a selectable marker for propagation in a host. Generally, a plasmid vector is introduced in a precipitate, such as a calcium phosphate precipitate, or in a complex with a charged lipid. If the vector is a virus, it may be packaged in vitro using an appropriate packaging cell line and then transduced into host cells.

The DNA insert should be operatively linked to an appropriate promoter, such as the phage lambda PL promoter, the E. coli lac. trp, phoA and tac promoters, the SV40 early and late promoters and promoters of retroviral LTRs, to name a few. Other suitable promoters will be known to the skilled artisan. The expression constructs will further contain sites for transcription initiation, termination and, in the transcribed region, a ribosome binding site for translation. The coding portion of the transcripts expressed by the constructs will preferably include a translation initiating codon at the beginning and a termination codon (UAA, UGA or UAG) appropriately positioned at the end of the polypeptide to be translated.

As indicated, the expression vectors will preferably include at least one selectable marker. Such markers include dihydrofolate reductase. G418 or neomycin resistance for eukaryotic cell culture and tetracycline, kanamycin or ampicillin resistance genes for culturing in E. coli and other bacteria. Representative examples of appropriate hosts include, but are not limited to, bacterial cells, such as E. coli, Streptomyces and Salmonella typhimurium cells; fungal cells, such as yeast cells; insect cells such as Drosophila S2 and Spodoptera Sf9 cells; animal cells such as CHO, COS, 293 and Bowes melanoma cells; and plant cells. Appropriate culture mediums and conditions for the above-described host cells are known in the art. Among vectors preferred for use in bacteria include pQΕ70, pQE60 and pQE-9, available from QIAGEN, Inc., supra; pBS vectors, Phagescript vectors, Bluescript vectors, pNH8A, pNHlόa, pNH18A, pNH46A, available from Stratagene; and ptrc99a, pKK223-3, pKK233-3. pDR540, pPJT5 available from Pharmacia. Among preferred eukaryotic vectors are pWLNEO, pSV2CAT, pOG44, pXTl and pSG available from Stratagene; and pSVK3, pBPV, pMSG and pSVL available from Pharmacia. Other suitable vectors will be readily apparent to the skilled artisan.

Introduction of the construct into the host cell can be effected by calcium phosphate transfection, DEAE-dextran mediated transfection, cationic lipid-mediated transfection, electroporation, transduction, infection or other methods. Such Methods are described in many standard laboratory manuals, such as Davis et a Basic Methods In Molecular Biology (1986).

The polypeptide may be expressed in a modified form, such as a fusion protein, and may include not only secretion signals, but also additional heterologous functional regions. For instance, a region of additional amino acids, particularly charged amino acids, may be added to the N-terminus of the polypeptide to improve stability and persistence in the host cell, during purification, or during subsequent handling and storage. Also, peptide moieties may be added to the polypeptide to facilitate purification. Such regions may be removed prior to final preparation of the polypeptide. The addition of peptide moieties to polypeptides to engender secretion or excretion, to improve stability and to facilitate purification, among others, are familiar and routine techniques in the art. A preferred fusion protein comprises a heterologous region from immunoglobulin that is useful to stabilize and purify proteins. For example. EP-A-O 464 533 (Canadian counterpart 2045869) discloses fusion proteins comprising various portions of constant region of immunoglobulin molecules together with another human protein or part thereof. In many cases, the Fc part in a fusion protein is thoroughly advantageous for use in therapy and diagnosis and thus results, for example, in improved pharmacokinetic properties (EP-A 0232 262). On the other hand, for some uses it would be desirable to be able to delete the Fc part after the fusion protein has been expressed, detected and purified in the advantageous manner described. This is the case when Fc portion proves to be a hindrance to use in therapy and diagnosis, for example when the fusion protein is to be used as antigen for immunizations. In drug discovery, for example, human proteins, such as hIL-5. have been fused with Fc portions for the purpose of high-throughput screening assays to identify antagonists of hLL-5. See, D. Bennett et al, J Molecular Recognition 8:52-58 (1995) and K. Johanson et al, J Biol. Chem. 270:9459-9471 (1995).

The LNFR-HKAEF92 protein can be recovered and purified from recombinant cell cultures by well-known methods including, ammonium sulfate or ethanol precipitation, acid extraction, anion or cation exchange chromatography, phosphocellulose chromatography, hydrophobic interaction chromatography, affinity chromatography, hydroxylapatite chromatography and lectin chromatography. Most preferably, high performance liquid chromatography ("HPLC") is employed for purification. Polypeptides of the present invention include: products purified from natural sources, including bodily fluids, tissues and cells, whether directly isolated or cultured; products of chemical synthetic procedures; and products produced by recombinant techniques from a prokaryotic or eukaryotic host, including, for example, bacterial, yeast, higher plant, insect and mammalian cells. Depending upon the host employed in a recombinant production procedure, the polypeptides of the present invention may be glycosylated or may be non-glycosylated. In addition, polypeptides of the invention may also include an initial modified methionine residue, in some cases as a result of host-mediated processes. Thus, it is well known in the art that the N-terminal methionine encoded by the translation initiation codon generally is removed with high efficiency from any protein after translation in all eukaryotic cells. While the N-terminal methionine on most proteins also is efficiently removed in most prokaryotes, for some proteins this prokaryotic removal process is inefficient, depending on the nature of the amino acid to which the N-terminal methionine is covalently linked.

Polypeptides and Fragments The invention further provides an isolated LNFR-HKAEF92 polypeptide having the amino acid sequence encoded by the deposited cDNA, or the amino acid sequence in SEQ ID NO:2, or a peptide or polypeptide comprising a portion of the above polypeptides.

Variant and Mutant Polypeptides

To improve or alter the characteristics of LNFR-HKAEF92 polypeptides, protein engineering may be employed. Recombinant DNA technology known to those skilled in the art can be used to create novel mutant proteins or "muteins including single or multiple amino acid substitutions, deletions, additions or fusion proteins. Such modified polypeptides can show, e.g., enhanced activity or increased stability. In addition, they may be purified in higher yields and show better solubility than the corresponding natural polypeptide, at least under certain purification and storage conditions.

N -Terminal and C-Terminal Deletion Mutants

For instance, for many proteins, including the extracellular domain of a membrane associated protein or the mature form(s ) of a secreted protein, it is known in the art that one or more amino acids may be deleted from the N-terminus or

C-terminus without substantial loss of biological function. For instance, Ron et al., J Biol. Chem., 268:2984-2988 (1993) reported modified KGF proteins that had heparin binding activity even if 3, 8, or 27 amino-terminal amino acid residues were missing. In the present case, since the protein of the invention is a member of the LNFRAL-IOR polypeptide family, deletions of N-terminal amino acids up to the cysteine at position 89of SEQ ID NO:2 may retain some biological activity such as such as ligand binding or modulation of target cell activities. Polypeptides having further N-terminal deletions including the cysteine residue at position 89 in SEQ ID NO:2 would not be expected to retain such biological activities because it is known that this residue in a INFR-ILlO-R-related polypeptide is required for ligand binding and signal transduction.

However, even if deletion of one or more amino acids from the N-terminus of a protein results in modification of loss of one or more biological functions of the protein, other biological activities may still be retained. Thus, the ability of the shortened protein to induce and/or bind to antibodies which recognize the complete or extracellular form of the protein generally will be retained when less than the majority of the residues of the complete or extracellular domain of the protein are removed from the N-terminus. Whether a particular polypeptide lacking N-terminal residues of a complete protein retains such immunologic activities can readily be determined by routine methods described herein and otherwise known in the art.

Accordingly, the present invention further provides polypeptides having one or more residues deleted from the amino terminus of the amino acid sequence of the LNFR-HKAEF92 shown in SEQ ID NO:2, up to the cysteine residue at position number 89, and polynucleotides encoding such polypeptides. In particular, the present invention provides polypeptides comprising the amino acid sequence of residues n-233 of SEQ ID NO:2, where n is an integer in the range of 19 to 89 and where cys-89 is the position of the first residue from the N-terminus of the complete LNFR-HKAEF92 polypeptide (shown in SEQ ID NO:2) believed to be required for ligand binding activity of the LNFR-HKAEF92 protein.

More in particular, the invention provides polynucleotides encoding polypeptides having the amino acid sequence of residues of 19-233, 20-233, 21-233, 22-233, 23-233, 24-233, 25-233. 26-233, 27-233. 28-233. 29-233, 30-233,-31-233, 32-233, 33-233, 34-233, 35-233, 36-233, 37-233, 38-233, 39-233. 40-233, 41-233, 42-233, 43-233, 44-233, 45-233. 46-233, 47-233, 48-233, 49-233, 50-233, 51-233, 52-233, 53-233, 54-233, 55-233, 56-233, 57-233, 58-233, 59-233, 60-233, 61-233, 62-233, 63-233, 64-233, 65-233, 66-233, 67-233, 68-233. 69-233, 70-233, 71-233, 72-233, 73-233, 74-233, 75-233. 76-233, 77-233, 78-233. 79-233, 80-233,81-233, 82-233, 83-233, 84-233, 85-233, 86-233, 87-233, 88-233 and 89-233of SEQ ID NO:2. Polynucleotides encoding these polypeptides also are provided.

Similarly, many examples of biologically functional C-terminal deletion muteins are known. For instance. Interferon gamma shows up to ten times higher activities by deleting 8-10 amino acid residues from the carboxy terminus of the protein (Dδbeli et al., J Biotechnology 7:199-216 (1988). In the present case, since the protein of the invention is a member of the LNFF/JLL-10R polypeptide family, deletions of C-terminal amino acids up to the cysteine at position-222 of SEQ ID NO: 2 may retain some biological activity such as ligand binding and signal transduction. Polypeptides having further C-terminal deletions including the cysteine residue at position 222 of SEQ ID NO:2 would not be expected to retain such biological activities because it is known that this residue in a LNFR/TL-lOR-related polypeptide is required for ligand binding and signal transduction.

However, even if deletion of one or more amino acids from the C-terminus of a protein results in modification of loss of one or more biological functions of the protein, other biological activities may still be retained. Thus, the ability of the shortened protein to induce and/or bind to antibodies which recognize the complete or extracellular portion of the protein generally will be retained when less than the majority of the residues of the complete or extracellular protein are removed from the C-terminus. Whether a particular polypeptide lacking C-terminal residues of a complete protein retains such immunologic activities can readily be determined by routine methods described herein and otherwise known in the an.

Accordingly, the present invention further provides polypeptides having one or more residues from the carboxy terminus of the amino acid sequence of the LNFR-HKAEF92 shown in SEQ ID NO:2, up to the cysteine residue at position 222 of SEQ ID NO:2, and polynucleotides encoding such polypeptides. In particular, the present invention provides polypeptides having the amino acid sequence of residues 19-m of the amino acid sequence in SEQ ID NO:2, where m is any integer in the range of 222-233 and where 222 is the position of the first residue from the C- terminus of the complete INFR-HKAEF92 polypeptide (shown in SEQ ID NO:2) believed to be required for ligand binding activity of the LNFR-HKAEF92 protein. More in particular, the invention provides polynucleotides encoding polypeptides having the amino acid sequence of residues 19-222, 19-223, 19-224, 19-225, 19-226, 19-227, 19-228, 19-229, 19-230, 19-231, 19-232 and 19-233 of SEQ ID NO:2. Polynucleotides encoding these polypeptides also are provided. The invention also provides polypeptides having one or more amino acids deleted from both the amino and the carboxyl termini, which may be described generally as having residues n-m of SEQ ID NO:2, where n and m are integers as described above. Polynucleotides encoding these polypeptides are also provided. Also included are a nucleotide sequence encoding a polypeptide consisting of a portion of the complete INFR-HKAEF92 amino acid sequence encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746, where this portion excludes from 18 to about 89 amino acids from the amino terminus of the complete amino acid sequence encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746. or from about 78 to about 89 amino acids from the carboxy terminus, or any combination of the above amino terminal and carboxy terminal deletions, of the complete amino acid sequence encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746. Polynucleotides encoding all of the above deletion mutant polypeptide forms also are provided.

Other Mutants

In addition to terminal deletion forms of the protein discussed above, it also will be recognized by one of ordinary skill in the art that some amino acid sequences of the INFR-HKAEF92 polypeptide can be varied without significant effect of the structure or function of the protein. If such differences in sequence are contemplated, it should be remembered that there will be critical areas on the protein which determine activity.

Thus, the invention further includes variations of the LNFR-HKAEF92 polypeptide which show substantial LNFR-HKAEF92 polypeptide activity or which include regions of LNFR-HKAEF92 protein such as the protein portions discussed below. Such mutants include deletions, insertions, inversions, repeats, and type substitutions selected according to general rules known in the art so as have little effect on activity. For example, guidance concerning how to make phenotypically silent amino acid substitutions is provided in Bowie. J. U. et al., "Deciphering the Message in Protein Sequences: Tolerance to Amino Acid Substitutions," Science 247:1306-1310 (1990). wherein the authors indicate that there are two main approaches for studying the tolerance of an amino acid sequence to change. The first method relies on the process of evolution, in which mutations are either accepted or rejected by natural selection. The second approach uses genetic engineering to introduce amino acid changes at specific positions of a cloned gene and selections or screens to identify sequences that maintain functionality.

As the authors state, these studies have revealed that proteins are surprisingly tolerant of amino acid substitutions. The authors further indicate which amino acid changes are likely to be permissive at a certain position of the protein. For example, most buried amino acid residues require nonpolar side chains, whereas few features of surface side chains are generally conserved. Other such phenotypically silent substitutions are described in Bowie, J. U. et al, supra, and the references cited therein. Typically seen as conservative substitutions are the replacements, one for another, among the aliphatic amino acids Ala, Val, Leu and lie; interchange of the hydroxyl residues Ser and Thr, exchange of the acidic residues Asp and Glu, substitution between the amide residues Asn and Gin. exchange of the basic residues Lys and Arg and replacements among the aromatic residues Phe, Tyr. Thus, the fragment, derivative or analog of the polypeptide of SEQ ID NO: 2, or that encoded by the deposited cDNA, may be (i) one in which one or more of the amino acid residues are substituted with a conserved or non-conserved amino acid residue (preferably a conserved amino acid residue) and such substituted amino acid residue may or may not be one encoded by the genetic code, or (ii) one in which one or more of the amino acid residues includes a substituent group, or (iii) one in which the soluble extracellular form of the polypeptide is fused with another compound, such as a compound to increase the half-life of the polypeptide (for example, polyethylene glycol), or (iv) one in which the additional amino acids are fused to the above form of the polypeptide, such as an IgG Fc fusion region peptide or leader or secretory sequence or a sequence which is employed for purification of the above form of the polypeptide or a proprotein sequence. Such fragments, derivatives and analogs are deemed to be within the scope of those skilled in the art from the teachings herein

Thus, the INFR-HKAEF92 of the present invention may include one or more amino acid substitutions, deletions or additions, either from natural mutations or human manipulation. As indicated, changes are preferably of a minor nature, such as conservative amino acid substitutions that do not significantly affect the folding or activity of the protein (see Table 1). TABLE 1. Conservative Amino Acid Substitutions.

Amino acids in the LNFR-HKAEF92 protein of the present invention that are essential for function can be identified by methods known in the art, such as site-directed mutagenesis or alanine-scanning mutagenesis (Cunningham and Wells, Science 244:1081-1085 (1989)). The latter procedure introduces single alanine mutations at every residue in the molecule. The resulting mutant molecules are then tested for biological activity such as receptor binding or in vitro or in vitro proliferative activity.

Of special interest are substitutions of charged amino acids with other charged or neutral amino acids which may produce proteins with highly desirable improved characteristics, such as less aggregation. Aggregation may not only reduce activity but also be problematic when preparing pharmaceutical formulations, because aggregates can be immunogemc (Pinckard et al, Clin. Exp. Immunol 2:331-340 (1967); Robbins et al. Diabetes 36: 838-845 (1987); Cleland et al, Crit. Rev. Therapeutic Drug Carrier Systems 10:301-311 (1993).

Replacement of amino acids can also change the selectivity of the binding of a ligand to cell surface receptors. For example, Ostade et al, Nature 361. -266-268 (1993) describes certain mutations resulting in selective binding of TNF-α to only one of the two known types of TNF receptors. Sites that are critical for ligand-receptor binding can also be determined by structural analysis such as crystallization, nuclear magnetic resonance or photoaffinity labeling (Smith et al, J. Mol Biol 224:899-904 (1992) and de Vos et al. Science 255:306-312 (1992)). Since INFR-HKAEF92 is a member of the INFR/ILIOR related protein family, to modulate rather than completely eliminate biological activities of LNFR-HKAEF92 preferably mutations are made in sequences encoding amino acids in the INFR-HKAEF92 conserved domain, more preferably in residues within this region which are not conserved in all members of the LNFR/LLIOR family. Also forming part of the present invention are isolated polynucleotides comprising nucleic acid sequences which encode the above LNFR-HKAEF92 mutants.

The invention further provides an isolated LNFR-HKAEF92 polypeptide comprising an amino acid sequence selected from the group consisting of: (a) the amino acid sequence shown as 1 to 311 of SEQ LD NO:2; (b) the amino acid sequence shown as 2 to 311 of SEQ ID NO:2; (c) the amino acid sequence shown as 30 to 311 of SEQ ID NO:2; (d) the amino acid sequence shown as 30 to 233 of SEQ ID NO:2; (e) the full length polypeptide encoded by the human cDNA clone HKAEF92; (f) the full length polypeptide except the N-terminal methoinine encoded by the human cDNA clone HKAEF92; (g) the mature polypeptide encoded by cDNA clone HKAEF92: and (h) the extracellular domain of the polypeptide encoded by cDNA clone HKAEF92.

Further polypeptides of the present invention include polypeptides which have at least 90% similarity, more preferably at least 95% similarity, and still more preferably at least 96%, 97%, 98% or 99% similarity to those described above. The polypeptides of the invention also comprise those which are at least 80% identical, more preferably at least 90% or 95% identical, still more preferably at least 96%, 97%, 98% or 99% identical to the polypeptide encoded by the deposited cDNA or to the polypeptide of SEQ ID NO:2, and also include portions of such polypeptides with at least 30 amino acids and more preferably at least 50 amino acids. By "% similarity" for two polypeptides is intended a similarity score produced by comparing the amino acid sequences of the two polypeptides using the Bestfit program (Wisconsin Sequence Analysis Package, Version 8 for Unix, Genetics Computer Group, University Research Park. 575 Science Drive, Madison, Wl 53711) and the default settings for determining similarity. Bestfit uses the local homology algorithm of Smith and Waterman (Advances in Applied Mathematics 2:482-489, 1981) to find the best segment of similarity between two sequences.

By a polypeptide having an amino acid sequence at least, for example, 95% "identical" to a reference amino acid sequence of a LNFR-HKAEF92 polypeptide is intended that the amino acid sequence of the polypeptide is identical to the reference sequence except that the polypeptide sequence may include up to five amino acid alterations per each 100 amino acids of the reference amino acid of the LNFR-HKAEF92 polypeptide. In other words, to obtain a polypeptide having an amino acid sequence at least 95% identical to a reference amino acid sequence, up to 5% of the amino acid residues in the reference sequence may be deleted, inserted or substituted with another amino acid. These alterations of the reference sequence may occur at the amino or carboxy terminal positions of the reference amino acid sequence or anywhere between those terminal positions, interspersed either individually among residues in the reference sequence or in one or more contiguous groups within the reference sequence.

As a practical matter, whether any particular polypeptide is at least 90%, 95%, 96%, 97%, 98% or 99% identical to, for instance., the amino acid sequence shown in SEQ ID NO:2 or to the amino acid sequence encoded by deposited cDNA clone can be determined conventionally using known computer programs such the Bestfit program (Wisconsin Sequence Analysis Package, Version 8 for Unix, Genetics Computer Group, University Research Park, 575 Science Drive, Madison, Wl 53711). When using Bestfit or any other sequence alignment program to determine whether a particular sequence is, for instance, 95% identical to a reference sequence according to the present invention, the parameters are set, of course, such that the percentage of identity is calculated over the full length of the reference amino acid sequence and that gaps in homology of up to 5% of the total number of amino acid residues in the reference sequence are allowed. The polypeptide of the present invention could be used as a molecular weight marker on SDS-PAGE gels or on molecular sieve gel filtration columns using methods well known to those of skill in the art.

As described in detail below, the polypeptides of the present invention can also be used to raise polyclonal and monoclonal antibodies, which are useful in assays for detecting LNFR-HKAEF92 protein expression as described below or as agonists and antagonists capable of enhancing or inhibiting LNFR-HKAEF92 protein function. Further, such polypeptides can be used in the yeast two-hybrid system to "capture" LNFR-HKAEF92 protein binding proteins which are also candidate agonists and antagonists according to the present invention. The yeast two hybrid system is described in Fields and Song, Nature 340:245-246 (1989).

Eptiope-Bearing Portions

In another aspect, the invention provides a peptide or polypeptide comprising an epitope-bearing portion of a polypeptide of the invention. The epitope of this polypeptide portion is an immunogenic or antigenic epitope of a polypeptide of the invention. An "immunogenic epitope" is defined as a part of a protein that elicits an antibody response when the whole protein is the immunogen. On the other hand, a region of a protein molecule to which an antibody can bind is defined as an "antigenic epitope." The number of immunogenic epitopes of a protein generally is less than the number of antigenic epitopes. See, for instance. Geysen et al, Proc. Natl Acad. Sci. USA 81:39944002 (1983).

As to the selection of peptides or polypeptides bearing an antigenic epitope (i.e., that contain a region of a protein molecule to which an antibody can bind), it is well known in that art that relatively short synthetic peptides that mimic part of a protein sequence are routinely capable of eliciting an antiserum that reacts with the partially mimicked protein. See, for instance, Sutcliffe, J. G Shinnick, T. M., Green, N. and Learner. R. A. (1983) "Antibodies that react with predetermined sites on proteins," Science. 219:660-666. Peptides capable of eliciting protein-reactive sera are frequently represented in the primary sequence of a protein, can be characterized by a set of simple chemical rules, and are confined neither to immunodominant regions of intact proteins (i.e., immunogenic epitopes) nor to the amino or carboxyl terminals. Antigenic epitope-bearing peptides and polypeptides of the invention are therefore useful to raise antibodies, including monoclonal antibodies, that bind specifically to a polypeptide of the invention. See, for instance, Wilson et al. Cell 37:767-778 (1984) at 777.

Antigenic epitope-bearing peptides and polypeptides of the invention preferably contain a sequence of at least seven, more preferably at least nine and most preferably between about 15 to about 30 amino acids contained within the amino acid sequence of a polypeptide of the invention. Non-limiting examples of antigenic polypeptides or peptides that can be used to generate LNFR-HKAEF92 specific antibodies include: a polypeptide comprising amino acid residues from about residue 69 to about residue 77, from about residue 92 to about residue 107, from about residue 129 to about residue 162, from about residue 172 to about 199, and from about 272 to about 307, all of SEQ ID NO:2. These polypeptide fragments have been determined to bear antigenic epitopes of the LNFR-HKAEF92 protein by the analysis of the Jameson-Wolf antigenic index, as shown in Figure 3, above.

The epitope-bearing peptides and polypeptides of the invention may be produced by any conventional means. See, e.g., Houghten, R. A. (1985) "General method for the rapid solid-phase synthesis of large numbers of peptides: specificity of antigen-antibody interaction at the level of individual amino acids." Proc. Natl. Acad. Sci. USA 82:5131-5135; this "Simultaneous Multiple Peptide Synthesis (SMPS)" process is further described in U.S. Patent No. 4,631,211 to Houghten et al. (1986).

Epitope-bearing peptides and polypeptides of the invention are used to induce antibodies according to methods well known in the art. See, for instance. Sutcliffe et al., supra; Wilson et al., supra: Chow, M. et al, Proc. Natl. Acad. Sci. USA 82:910-914; and Bittle, F. J. et al. J. Gen. Virol. 66:2347-2354 (1985). Immunogenic epitope-bearing peptides of the invention, i.e., those parts of a protein that elicit an antibody response when the whole protein is the immunogen, are identified according to methods known in the art. See, for instance, Geysen et al., supra. Further still, U.S. Patent No. 5,194,392 to Geysen (1990) describes a general method of detecting or determining the sequence of monomers (amino acids or other compounds) which is a topological equivalent of the epitope (i.e., a "mimotope") which is complementary to a particular paratope (antigen binding site) of an antibody of interest. More generally, U.S. Patent No. 4,433,092 to Geysen (1989) describes a method of detecting, or determining a sequence of monomers which is a topographical equivalent of a ligand which is complementary to the ligand binding site of a particular receptor of interest. Similarly, U.S. Patent No. 5,480,971 to Houghten, R. A. et al. (1996) on Peralkylated Oligopeptide Mixtures discloses linear Cl-C7-alkyl peralkylated oligopeptides and sets and libraries of such peptides, as well as methods for using such oligopeptide sets and libraries for determining the sequence of a peralkylated oligopeptide that preferentially binds to an acceptor molecule of interest. Thus, non-peptide analogs of the epitope-bearing peptides of the invention also can be made routinely by these methods.

Fusion Proteins As one of skill in the art will appreciate, LNFR-HKAEF92 polypeptides of the present invention and the epitope-bearing fragments thereof described above can be combined with parts of the constant domain of immunoglobulins (IgG), resulting in chimeric polypeptides. These fusion proteins facilitate purification and show an increased half-life in vivo. This has been shown, e.g., for chimeric proteins consisting of the first two domains of the human CD4-polypeptide and various domains of the constant regions of the heavy or light chains of mammalian immunoglobulins (EP A 394,827; Traunecker et al., Nature 331:84-86(1988)). Fusion proteins that have a disulfide-linked dimeric structure due to the IgG part can also be more efficient in binding and neutralizing other molecules than the monomeric LNFR-HKAEF92 protein or protein fragment alone (Fountoulakis et al., J Biochem. 270:3958-3964 (1995)).

Antibodies

INFR-HKAEF92 -protein specific antibodies for use in the present invention can be raised against the intact INFR-HKAEF92 protein or an antigenic polypeptide fragment thereof, which may be presented together with a carrier protein, such as an albumin, to an animal system (such as rabbit or mouse) or, if it is long enough (at least about 25 amino acids), without a carrier.

As used herein, the term "antibody" (Ab) or "monoclonal antibody" (Mab) is meant to include intact molecules as well as antibody fragments (such as, for example, Fab and F(ab^')2 fragments) which are capable of specifically binding to LNFR-HKAEF92 protein. Fab and F(ab')2 fragments lack the Fc fragment of intact antibody, clear more rapidly from the circulation, and may have less non-specific tissue binding of an intact antibody (Wahl et al., J Nucl Med. 24:316-325 (1983)). Thus, these fragments are preferred.

The antibodies of the present invention may be prepared by any of a variety of methods. For example, cells expressing the LNFR-HKAEF92 protein or an antigenic fragment thereof can be administered to an animal in order to induce the production of sera containing polyclonal antibodies. In a preferred method, a preparation of LNFR-HKAEF92 protein is prepared and purified to render it substantially free of natural contaminants. Such a preparation is then introduced into an animal in order to produce polyclonal antisera of greater specific activity. In the most preferred method, the antibodies of the present invention are monoclonal antibodies (or INFR-HKAEF92 protein binding fragments thereof). Such monoclonal antibodies can be prepared using hybridoma technology (Kδhler et al, Nature 256:495 (1975); Kδhler et al, Eur. J Immitnol. 6:511 (1976); Kδhler et al., EMr. J. Immunol. 6:292 (1976); Hammerling et al., in: Monoclonal Antibodies and T-Cell Hybridomas. Elsevier, N.Y., (1981) pp. 563-681). In general, such procedures involve immunizing an animal (preferably a mouse) with a INFR-HKAEF92 protein antigen or, more preferably, with a LNFR-HKAEF92 protein-expressing cell. Suitable cells can be recognized by their capacity to bind anti-LNFR-HKAEF92 protein antibody. Such cells may be cultured in any suitable tissue culture medium; however, it is preferable to culture cells in Earle's modified Eagle's medium supplemented with 10% fetal bovine serum (inactivated at about 56°C), and supplemented with about 10 g/1 of nonessential amino acids, about 1,000 U/ml of penicillin, and about 100 μg/ml of streptomycin. The splenocytes of such mice are extracted and fused with a suitable myeloma cell line. Any suitable myeloma cell line may be employed in accordance with the present invention; however, it is preferable to employ the parent myeloma cell line (SP20), available from the American Type Culture Collection, Rockville, Maryland. After fusion, the resulting hybridoma cells are selectively maintained in HAT medium, and then cloned by limiting dilution as described by Wands et al. (Gastroenterology 80:225-232 ( 1981)). The hybridoma cells obtained through such a selection are then assayed to identify clones which secrete antibodies capable of binding the LNFR-HKAEF92 protein antigen.

Alternatively, additional antibodies capable of binding to the LNFR- HKAEF92 protein antigen may be produced in a two-step procedure through the use of anti-idiotypic antibodies. Such a method makes use of the fact that antibodies are themselves antigens, and that, therefore, it is possible to obtain an antibody which binds to a second antibody. In accordance with this method, INFR-HKAEF92-protein specific antibodies are used to immunize an animal. preferably a mouse. The splenocytes of such an animal are then used to produce hybridoma cells, and the hybridoma cells are screened to identify clones which produce an antibody whose ability to bind to the LNFR-HKAEF92 protein-specific antibody can be blocked by the LNFR-HKAEF92 protein antigen. Such antibodies comprise anti-idiotypic antibodies to the LNFR-HKAEF92 protein-specific antibody and can be used to immunize an animal to induce formation of further INFR-HKAEF92 protein-specific antibodies.

It will be appreciated that Fab and F(ab')2 and other fragments of the antibodies of the present invention may be used according to the methods disclosed herein. Such fragments are typically produced by proteolytic cleavage, using enzymes such as papain (to produce Fab fragments) or pepsin (to produce F(ab')2 fragments). Alternatively, LNFR-HKAEF92 protein-binding fragments can be produced through the application of recombinant DNA technology or through synthetic chemistry.

For in vivo use of anti-LNFR-HKAEF92 in humans, it may be preferable to use "humanized" chimeric monoclonal antibodies. Such antibodies can be produced using genetic constructs derived from hybridoma cells producing the monoclonal antibodies described above. Methods for producing chimeric antibodies are known in the art. See, for review, Morrison, Science 229:1202 ( 1985); Oi et al., BioTechniques 4:214 (1986); Cabilly et al., U.S. Patent No. 4.1816,567; Taniguchi et al., EP 171496; Morrison et al., EP 173494; Neuberger et al., WO 8601533; Robinson et al., WO 8702671; Boulianne et al. Nature 312:643 (1984); Neuberger et al, Nature 314:268 (1985).

Immune System-Related Disorders Diagnosis

For a number of immune system-related disorders, substantially altered (increased or decreased) levels of LNFR-HKAEF92 gene expression can be detected in immune system tissue or other cells or bodily fluids (e.g., sera, plasma, urine, synovial fluid or spinal fluid) taken from an individual having such a disorder, relative to a "standard" LNFR-HKAEF92 gene expression level, that is, the LNFR-HKAEF92 expression level in immune system tissues or bodily fluids from an individual not having the immune system disorder. Thus, the invention provides a diagnostic method useful during diagnosis of an immune system disorder, which involves measuring the expression level of the gene encoding the LNFR-HKAEF92 protein in immune system tissue or other cells or body fluid from an individual and comparing the measured gene expression level with a standard LNFR-HKAEF92 gene expression level, whereby an increase or decrease in the gene expression level compared to the standard is indicative of an immune system disorder. In particular, it is believed that certain tissues in mammals with cancer express significantly altered levels of the LNFR-HKAEF92 protein and mRNA encoding the INFR-HKAEF92 protein when compared to a corresponding "standard" level. Further, it is believed that enhanced levels of the LNFR-HKAEF92 protein can be detected in certain body fluids (e.g., sera, plasma, urine, and spinal fluid) from mammals with such a cancer when compared to sera from mammals of the same species not having the cancer.

Thus, the invention provides a diagnostic method useful during diagnosis of an immune system disorder, which involves measuring the expression level of the gene encoding the LNFR-HKAEF92 protein in immune system tissue or other cells or body fluid from an individual and comparing the measured gene expression level with a standard LNFR-HKAEF92 gene expression level, whereby an increase or decrease in the gene expression level compared to the standard is indicative of an immune system disorder.

Where a diagnosis of a disorder in the immune system has already been made according to conventional methods, the present invention is useful as a prognostic indicator, whereby patients exhibiting altered gene expression will experience a worse clinical outcome relative to patients expressing the gene at a level nearer the standard level.

By "assaying the expression level of the gene encoding the LNFRHKAEF92 protein" is intended qualitatively or quantitatively measuring or estimating the level of the LNFR-HKAEF92 protein or the level of the mRNA encoding the INFR-HKAEF92 protein in a first biological sample either directly (e.g., by determining or estimating absolute protein level or mRNA level) or relatively (e.g., by comparing to the LNFR-HKAEF92 protein level or mRNA level in a second biological sample). Preferably, the LNFR-HKAEF92 protein level or mRNA level in the first biological sample is measured or estimated and compared to a standard LNFR-HKAEF92 protein level or mRNA level, the standard being taken from a second biological sample obtained from an individual not having the disorder or being determined by averaging levels from a population of individuals not having a disorder of the immune system. As will be appreciated in the art, once a standard LNFR-HKAEF92 protein level or mRNA level is known, it can be used repeatedly as a standard for comparison.

By "biological sample" is intended any biological sample obtained from an individual, body fluid, cell line, tissue culture, or other source, which contains

INFR-HKAEF92 protein or mRNA. As indicated, biological samples include body fluids (such as sera, plasma, urine, synovial fluid and spinal fluid) which contain free soluble extracellular domains of LNFR-HKAET92 protein, immune system tissue, and other tissue sources found to express complete or extracellular domain of the LNFR-HKAEF92 or a LNFR-HKAEF92 receptor. Methods for obtaining tissue biopsies and body fluids from mammals are well known in the art. Where the biological sample is to include mRNA, a tissue biopsy is the preferred source.

The present invention is useful for diagnosis or treatment of various immune system-related disorders in mammals, preferably humans. Such disorders include inflammatory disorders, persistent infection and any disregulation of immune cell function including, but not limited to. autoimmunity, arthritis, leukemias, lymphomas, immunosuppression, immunity, humoral immunity, inflammatory bowel disease, myelo suppression, and the like.

Total cellular RNA can be isolated from a biological sample using any suitable technique such as the single-step guanidinium-thiocyanate-phenol chloroform method described in Chomczynski and Sacchi, Anal. Biochem. 162: 156-159 (1987). Levels of mRNA encoding the INFR-HKAEF92 protein are then assayed using any appropriate method. These include Northern blot analysis, S 1 nuclease mapping, the polymerase chain reaction (PCR), reverse transcription in combination with the polymerase chain reaction (RT-PCR), and reverse transcription in combination with the ligase chain reaction (RT-LCR).

Assaying LNFR-HKAEF92 protein levels in a biological sample can occur using antibody-based techniques. For example, INFR-HKAEF92 protein expression in tissues can be studied with classical immunohistological methods (Jalkanen, M., et al., J Cell Biol 101:976-985 (1985): Jalkanen, M., et al, J Cell . Biol 105:3087-3096 (1987)). Other antibody-based methods useful for detecting LNFR-HKAEF92 protein gene expression include immunoassays, such as the enzyme linked immunosorbent assay (ELISA) and the radioimmunoassay (RIA). Suitable antibody assay labels are known in the art and include enzyme labels, such as, glucose oxidase, and radioisotopes, such as iodine (¹²⁵I, ¹²¹I), carbon (^l4C), sulfur (³⁵S), tritium (³H), indium (¹¹²In), and technetium (""Tc), and fluorescent labels, such as fluorescein and rhodamine, and biotin.

In addition to assaying LNFR-HKAEF92 protein levels in a biological sample obtained from an individual, LNFR-HKAEF92 protein can also be detected in vivo by imaging. Antibody labels or markers for in vivo imaging of LNFR-HKAEF92 protein include those detectable by X-radiography, NMR or ESR. For X-radiography, suitable labels include radioisotopes such as barium or cesium, which emit detectable radiation but are not overtly harmful to the subject. Suitable markers for NMR and ESR include those with a detectable characteristic spin, such as deuterium, which may be incoφorated into the antibody by labeling of nutrients for the relevant hybridoma.

A LNFR-HKAEF92 protein-specific antibody or antibody fragment which has been labeled with an appropriate detectable imaging moiety, such as a radioisotope (for example, ¹³¹I, "²In. "Tc), a radio-opaque substance, or a material detectable by nuclear magnetic resonance, is introduced (for example, parenterally, subcutaneously or intraperitoneally) into the mammal to be examined for immune system disorder. It will be understood in the an that the size of the subject and the imaging system used will determine the quantity of imaging moiety needed to produce diagnostic images. In the case of a radioisotope moiety, for a human subject, the quantity of radioactivity injected will normally range from about 5 to 20 millicuries of "^mTc. The labeled antibody or antibody fragment will then preferentially accumulate at the location of cells which contain LNFR-HKAEF92 protein. In vivo tumor imaging is described in S.W. Burchiel et al.,"Lmmunopharmacokinetics of Radiolabeled Antibodies and Their Fragments" (Chapter 1-3 in Tumor Imaging: The Radiochemical Detection of Cancer. S.W. Burchiel and B. A. Rhodes, eds.. Masson Publishing Inc. ( 1982)). Treatment

As noted above. LNFR-HKAEF92 polynucleotides and polypeptides are useful for diagnosis of conditions involving abnormally high or low expression of INFR-HKAEF92 activities. Given the cells and tissues where LNFR-HKAEF92 is expressed as well as the activities modulated by LNFR-HKAEF92, it is readily apparent that a substantially altered (increased or decreased) level of expression of INFR-HKAEF92 in an individual compared to the standard or "normal" level produces pathological conditions related to the bodily system(s) in which LNFR- HKAEF92 is expressed and/or is active.

It will also be appreciated by one of ordinary skill that, since the LNFR- HKAEF92 protein of the invention is a member of the LNFR/LL 10R family the extracellular domain of the protein may be released in soluble form from the cells which express the LNFR-HKAEF92 by proteolytic cleavage. Therefore, when INFR-HKAEF92 soluble extracellular domain is added from an exogenous source to cells, tissues or the body of an individual, the protein will exert its physiological activities on its target cells of that individual. Also, cells expressing this transmembrane protein may be added to cells, tissues or the body of an individual and these added cells will bind to cells expressing receptor for LNFR-HKAEF92, whereby the cells expressing LNFR-HKAEF92 can cause actions on the receptor-bearing target cells.

Therefore, it will be appreciated that conditions caused by a decrease in the standard or normal level of LNFR-HKAEF92 activity in an individual, particularly disorders of the immune system, can be treated by administration of INFR-HKAEF92 polypeptide in the form of soluble extracellular domain or cells expressing the complete protein. Thus, the invention also provides a method of treatment of an individual in need of an increased level of LNFR-HKAEF92 activity comprising administering to such an individual a pharmaceutical composition comprising an amount of an isolated LNFR-HKAEF92 polypeptide of the invention, effective to increase the LNFR-HKAEF92 activity level in such an individual.

Formulations

The LNFR-HKAEF92 polypeptide composition will be formulated and dosed in a fashion consistent with good medical practice, taking into account the clinical condition of the individual patient (especially the side effects of treatment with LNFR-HKAEF92 polypeptide alone), the site of delivery of the INFR-HKAEF92 polypeptide composition, the method of administration, the scheduling of administration, and other factors known to practitioners. The "effective amount" of INFR-HKAEF92 polypeptide for purposes herein is thus determined by such considerations.

As a general proposition, the total pharmaceutically effective amount of LNFR-HKAEF92 polypeptide administered parenterally per dose will be in the range of about 1 μg/kg/day to 10 mg/kg/day of patient body weight, although, as noted above, this will be subject to therapeutic discretion. More preferably, this dose is at least 0.01 mg/kg/day, and most preferably for humans between about 0.01 and 1 mg/kg/day for the hormone. If given continuously, the LNFR-HKAEF92 polypeptide is typically administered at a dose rate of about 1 μg kg/hour to about 50 μg/kg/hour, either by 1-4 injections per day or by continuous subcutaneous infusions, for example, using a mini-pump. An intravenous bag solution may also be employed. The length of treatment needed to observe changes and the interval following treatment for responses to occur appears to vary depending on the desired effect.

Pharmaceutical compositions containing the LNFR-HKAEF92 of the invention may be administered orally, rectally, parenterally, intracistemally, intravaginally, intraperitoneally, topically (as by powders, ointments, drops or transdermal patch), bucally, or as an oral or nasal spray. By "pharmaceutically acceptable carrier" is meant a non-toxic solid, semisolid or liquid filler, diluent, encapsulating material or formulation auxiliary of any type. The term "parenteral" as used herein refers to modes of administration which include intravenous, intramuscular, intraperitoneal, intrastemal, subcutaneous and intraarticular injection and infusion.

The LNFR-HKAEF92 polypeptide is also suitably administered by sustained-release systems. Suitable examples of sustained-release compositions include semi-permeable polymer matrices in the form of shaped articles, e.g., films, or mirocapsules. Sustained-release matrices include polylactides (U.S. Pat. No.

3,773,919, EP 58,481), copolymers of L-glutamic acid and gamma-ethyl-L glutamate (Sidman, U. et al., Biopolymers 22:547-556 (1983)), poly (2-hydroxyethyl methacrylate) (R. Langer et al., J. Biomed Mater. Res. 15:167-277 (1981), and R. Langer, Chem. Tech. 12:98-105 (1982)). ethylene vinyl acetate (R.Langer et al.. Id.) or poly-D- (+3-hydroxybutyπc acid (EP 133,988). Sustained release INFR-HKAEF92 polypeptide compositions also include liposomally entrapped INFR-HKAEF92 polypeptide. Liposomes containing LNFR-HKAEF92 polypeptide are prepared by methods known per se: DE 3,218,121; Epstein et al., Proc. Natl. Acad. Sci. (USA) 82:3688-3692 (1985); Hwana et al., Proc. Natl. Acad. Sci. (USA) 77:4030-4034 (1980): EP 52,322; EP 36,676; EP 88,046; EP 143,949; EP 142,641; Japanese Pat. Appl. 83-118008; U.S. Pat. Nos. 4,485,045 and 4,544,545; and EP 102,324. Ordinarily, the liposomes are of the small (about 200-800 Angstroms) unilamellar type in which the lipid content is greater than about 30 mol. percent cholesterol, the selected proportion being adjusted for the optimal INFR-HKAEF92 polypeptide therapy.

For parenteral administration, in one embodiment, the LNFR-HKAEF92 polypeptide is formulated generally by mixing it at the desired degree of purity, in a unit dosage injectable form (solution, suspension, or emulsion), with a pharmaceutically acceptable carrier, i.e., one that is non-toxic to recipients at the dosages and concentrations employed and is compatible with other ingredients of the formulation. For example, the formulation preferably does not include oxidizing agents and other compounds that are known to be deleterious to polypeptides.

Generally, the formulations are prepared by contacting the LNFR-HKAEF92 polypeptide uniformly and intimately with liquid carriers or finely divided solid carriers or both. Then, if necessary, the product is shaped into the desired formulation. Preferably the carrier is a parenteral carrier, more preferably a solution that is isotonic with the blood of the recipient. Examples of such carrier vehicles include water, saline. Ringer's solution, and dextrose solution. Nonaqueous vehicles such as fixed oils and ethyl oleate are also useful herein, as well as liposomes.

The earner suitably contains minor amounts of additives such as substances that enhance isotonicity and chemical stability. Such materials are non-toxic to recipients at the dosages and concentrations employed, and include buffers such as phosphate, citrate, succinate, acetic acid, and other organic acids or their salts; antioxidants such as ascorbic acid; low molecular weight (less than about ten residues) polypeptides, e.g., polyarginine or tripeptides; proteins, such as serum albumin, gelatin, or immunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone; amino acids, such as glycine, glutamic acid, aspartic acid, or arginine; monosaccharides, disaccharides, and other carbohydrates including cellulose or its derivatives, glucose, manose, or dextrins; chelating agents such as EDTA; sugar alcohols such as mannitol or sorbitol: counterions such as sodium; and/or nonionic surfactants such as polysorbates, poloxamers, or PEG.

The LNFR-HKAEF92 polypeptide is typically formulated in such vehicles at a concentration of about 0.1 mg/ml to 100 mg/ml. preferably 1-10 mg/ml, at a pH of about 3 to 8. It will be understood that the use of certain of the foregoing excipients, carriers, or stabilizers will result in the formation of LNFR-HKAEF92 polypeptide salts.

LNFR-HKAEF92 polypeptide to be used for therapeutic administration must be sterile. Sterility is readily accomplished by filtration through sterile filtration membranes (e.g., 0.2 micron membranes). Therapeutic LNFR-HKAEF92 polypeptide compositions generally are placed into a container having a sterile access port, for example, an intravenous solution bag or vial having a stopper pierceable by a hypodermic injection needle. LNFR-HKAEF92 polypeptide ordinarily will be stored in unit or multi- dose containers, for example, sealed ampoules or vials, as an aqueous solution or as a lyophilized formulation for reconstitution. As an example of a lyophilized formulation, 10-ml vials are- filled with 5 ml of sterile-filtered 1 % (w/v) aqueous LNFR-HKAEF92 polypeptide solution, and the resulting mixture is lyophilized. The infusion solution is prepared by reconstituting the lyophilized LNFR- HKAEF92 polypeptide using bacteriostatic Water-for-Injection.

The invention also provides a pharmaceutical pack or kit comprising one or more containers filled with one or more of the ingredients of the pharmaceutical compositions of the invention. Associated with such container(s) can be a notice in the form prescribed by a governmental agency regulating the manufacture, use or sale of pharmaceuticals or biological products, which notice reflects approval by the agency of manufacture, use or sale for human administration. In addition, the polypeptides of the present invention may be employed in conjunction with other therapeutic compounds.

Gene Mapping

The nucleic acid molecules of the present invention are also valuable for chromosome identification. The sequence is specifically targeted to and can hybridize with a particular location on an individual human chromosome. Moreover, there is a current need for identifying particular sites on the chromosome. Few chromosome marking reagents based on actual sequence data (repeat polymorphisms) are presently available for marking chromosomal location. The mapping of DNAs to chromosomes according to the present invention is an important first step in correlating those sequences with genes associated with disease.

In certain prefened embodiments in this regard, the cDNA herein disclosed is used to clone genomic DNA of a LNFR-HKAEF92 protein gene. This can be accomplished using a variety of well known techniques and libraries, which generally are available commercially. The genomic DNA then is used for in situ chromosome mapping, using well known techniques for this purpose.

In addition, in some cases, sequences can be mapped to chromosomes by preparing PCR primers (preferably 15-25 bp) from the cDNA. Computer analysis of the 3' untranslated section of the gene is used to rapidly select primers that do not span more than one exon in the genomic DNA, thus complicating the amplification process.

These primers are then used for PCR screening of somatic cell hybrids containing individual human chromosomes. Fluorescence in situ hybridization ("FISH") of a cDNA clone to a metaphase chromosomal spread can be used to provide a precise chromosomal location in one step. This technique can be used with probes from the cDNA as short as 50 or 60 bp. For a review of this technique, see Verma et al, Human Chromosomes: A Manual Of Basic Techniques, Pergamon Press. New York (1988).

Once a sequence has been mapped to a precise chromosomal location, the physical position of the sequence on the chromosome can be corcelated with genetic map data. Such data are found, for example, in V. McKusick, Mendelian Inheritance In Man, available on-line through Johns Hopkins University, Welch Medical Library. The relationship between genes and diseases that have been mapped to the same chromosomal region are then identified through linkage analysis (coinheritance of physically adjacent genes). Next, it is necessary to determine the differences in the cDNA or genomic sequence between affected and unaffected individuals. If a mutation is observed in some or all of the affected individuals but not in any normal individuals, then the mutation is likely to be the causative agent of the disease. Having generally described the invention, the same will be more readily understood by reference to the following examples, which are provided by way of illustration and are not intended as limiting.

Examples

Example 1: Isolation of the INFR-HKAEF92 cDNA Clones From the Deposited Samples

The cDNA encoding LNFR-HKAEF92 is inserted into the Sal I and Not I restriction sites of the multiple cloning site of pCMVSport. pCMVSport contains an ampicillin resistance gene and may be transformed into E. coli strain DH10B, available from Life Technologies (see, for instance. Gruber, C. E.. et al., Focus 15:59 (1993)).

Two approaches can be used to isolate LNFR-HKAEF92 from the deposited sample. First, a specific polynucleotide of SEQ ID NO: 1 with 30-40 nucleotides is synthesized using an Applied Biosystems DNA synthesizer according to the sequence reported. The oligonucleotide is labeled, for instance, with ³²P-γ-ATP using T4 polynucleotide kinase and purified according to routine methods (e.g., Maniatis, et al, Molecular Cloning: A Laboratory Manual. Cold Spring Harbor Press, Cold Spring, NY (1982)). The plasmid mixture is transformed into a suitable host (such as XL-1 Blue (Stratagene)) using techniques known to those of skill in the art, such as those provided by the vector supplier or in related publications or patents. The transformants are plated on 1.5% agar plates (containing the appropriate selection agent, e.g., ampicillin) to a density of about 150 transformants (colonies) per piate. These plates are screened using Nylon membranes according to routine methods for bacterial colony screening (e.g., Sambrook. et al., Molecular Cloning: A Laboratory Manual, 2nd Edit., (1989), Cold Spring Harbor Laboratory Press, pages 1.93 to 1.104), or other techniques known to those of skill in the art.

Alternatively, two primers of 17-20 nucleotides derived from both ends of the SEQ ID NO: 1 (i.e., within the region of SEQ ID NO: 1 bounded by the 5' and 3' nucleotides of the clone) are synthesized and used to amplify the INFR-HKAEF92 cDNA using the deposited cDNA plasmid as a template. The polymerase chain reaction is carried out under routine conditions, for instance, in 25 μl of reaction mixture with 0.5 μg of the above cDNA template. A convenient reaction mixture is 1.5-5 mM MgCl₂, 0.01% (w/v) gelatin, 20 μM each of dATP, dCTP, dGTP, dTTP, 25 pmol of each primer and 0.25 Unit of Taq polymerase. Thirty five cycles of PCR (denaturation at 94°C for 1 min: annealing at 55°C for 1 min; elongation at 72°C for 1 min) are performed with a Perkin-Elmer Cetus automated thermal cycler. The amplified product is analyzed by agarose gel electrophoresis and the DNA band with expected molecular weight is excised and purified. The PCR product is verified to be the selected sequence by subcloning and sequencing the DNA product.

Example 2: Isolation of INFR-HKAEF92 Genomic Clones

A human genomic PI library (Genomic Systems, Inc.) is screened by PCR using primers selected for the cDNA sequence corresponding to SEQ ID NO: 1, according to the method described in Example 1 (see also. Sambrook. et al, supra).

Example 3: Tissue Distribution of INFR-HKAEF92

Tissue distribution of mRNA expression of LNFR-HKAEF92 is determined using protocols for Northern blot analysis, described by, among others, Sambrook and colleagues (supra). For example, an LNFR-HKAEF92 probe produced by the method described in Example 1 is labeled with ³²P using the rediprime™ DNA labeling system (Amersham Life Science), according to manufacturer's instructions.

After labeling, the probe is purified using a CHROMA SPLN-100™ column (Clontech Laboratories, Inc.), according to manufacturer's protocol number

PT 1200-1. The purified labeled probe is then used to examine various human tissues for mRNA expression.

Multiple Tissue Northern (MTN) blots containing various human tissues (H) or human immune system (IM) tissues (Clontech) are examined with the labeled probe using ExpressHyb™ hybridization solution (Clontech) according to manufacturer's protocol number PT 1190-1. Following hybridization and washing, the blots are mounted and exposed to film at -70°C overnight, and the films developed according to standard procedures.

Example 4: Chromosomal Mapping of INFR-HKAEF92

An oligonucleotide primer set is designed according to the sequence at the 5' end of SEQ ID NO: 1. This primer preferably spans about 100 nucleotides. This primer set is then used in a polymerase chain reaction under the following set of conditions: 30 seconds, 95°C; 1 minute, 56°C; 1 minute, 70°C. This cycle is repeated 32 times followed by one 5 minute cycle at 70°C. Human, mouse, and hamster DNA is used as template in addition to a somatic cell hybrid panel containing individual chromosomes or chromosome fragments (Bios. Inc). The reactions are analyzed on either 8% polyacrylamide gels or 3.5 % agarose gels. Chromosome mapping is determined by the presence of an approximately 100 bp PCR fragment in the particular somatic cell hybrid.

Example 5: Bacterial Expression of INFR-HKAEF92

An LNFR-HKAEF92 polynucleotide encoding an LNFR-HKAEF92 polypeptide of the invention is amplified using PCR oligonucleotide primers corresponding to the 5' and 3' ends of the DNA sequence, as outlined in Example 1, to synthesize insertion fragments. The primers used to amplify the cDNA insen should preferably contain restriction sites, such as Bam HI and Hin dill, at the 5' end of the primers in order to clone the amplified product into the expression vector. For example, Bam HI and Hin dm correspond to the restriction enzyme sites on the bacterial expression vector pQE-9 (Qiagen Inc., Chatsworth. CA). This plasmid vector encodes antibiotic resistance (AMP^R) , a bacterial origin of replication (ori), an IPTG-regulatable promoter/operator (P/O), a ribosome binding site (RBS), a 6-histidine tag (6-His), and restriction enzyme cloning sites. Specifically, to clone the soluble extracellular domain of the LNFR-

HKAEF92 protein in a bacterial vector, the 5' primer has the sequence 5'-CATATGACAGATGAAGTGGCCATTC-3' (SEQ LD NO: 12) containing the underlined Nde I restriction site followed several nucleotides of the amino terminal coding sequence of the soluble extracellular domain LNFR-HKAEF92 sequence in SEQ ID NO: 1. One of ordinary skill in the art would appreciate, of course, that the point in the protein coding sequence where the 5' primer begins may be varied to amplify a DNA segment encoding any desired portion of the complete INFR- HKAEF92 protein shorter or longer than the extracellular form of the protein. The 3' primer has the sequence 5'-GGTACCTTACACCATGAAAGCCCCG-3' (SEQ ID NO: 13) containing the underlined. Asp 718 restriction site followed by a number nucleotides complementary to the 3' end of the coding sequence of the INFR-HKAEF92 DNA sequence of SEQ ID NO: 1.

The pQE-9 vector is digested with Nde I and Asp 718 and the amplified fragment is ligated into the pQE-9 vector maintaining the reading frame initiated at the bacterial RBS. The ligation mixture is then used to transform the E. coli strain M15/rep4 (Qiagen, Inc.) which contains multiple copies of the plasmid pREP4. which expresses the lad repressor and also confers kanamycin resistance (Kan^R). Transformants are identified by their ability to grow on LB plates and colonies are selected which are resistant to both ampicillin and kanamycin. Plasmid DNA is isolated and confirmed by restriction analysis.

Clones containing the desired constructs are grown overnight (O/N) in liquid culture in LB media supplemented with both Amp (100 μg/ml) and Kan (25 μg/ml). The O/N culture is used to inoculate a large culture at a ratio of 1 : 100 to 1 :250. The cells are grown to an optical density 600 (O.D-600^) of between 0.4 and 0.6. IPTG (Isopropyl-B-D-thiogalacto pyranoside) is then added to a final concentration of 1 mM. IPTG induces by inactivating the lad repressor. clearing the promoter/operator leading to increased gene expression.

Cells are grown for an additional 3 to 4 hours. Cells are then harvested by centrifugation (20 mins at 6000 X g). The cell pellet is solubilized in the chaotropic agent 6 M Guanidine-HCl by stirring for 3-4 hours at 4°C. The cell debris is removed by centrifugation, and the supernatant containing the polypeptide is loaded onto a nickel-nitrilo-tri-acetic acid ("Ni-NTA") affinity resin column (QIAGEN, Inc., supra). Proteins with a 6 x His tag bind to the Ni-NTA resin with high affinity and can be purified in a simple one-step procedure (for details see: The QlAexpressionist (1995) QIAGEN, Inc., supra).

Briefly, the supernatant is loaded onto the column in 6 M guanidine-HCl, pH 8, the column is first washed with 10 volumes of 6 M guanidine-HCl, pH 8, then washed with 10 volumes of 6 M guanidine-HCl pH 6. and finally the polypeptide is eluted with 6 M guanidine-HCl, pH 5.

The purified LNFR-HKAEF92 protein is then renatured by dialyzing it against phosphate-buffered saline (PBS) or 50 mM Na-acetate, pH 6 buffer plus 200 mM NaCl. Alternatively, the LNFR-HKAEF92 protein can be successfully refolded while immobilized on the Ni-NTA column. The recommended conditions are as follows: renature using a linear 6M-1M urea gradient in 500 mM NaCl, 20% glycerol, 20 mM Tris/HCl pH 7.4, containing protease inhibitors. The renaturation should be performed over a period of 1.5 hours or more. After renaturation the proteins are eluted by the addition of 250 mM immidazole. Immidazole is removed by a final dialyzing step against PBS or 50 mM sodium acetate pH 6 buffer plus 200 mM NaCl. The purified INFR-HKAEF92 protein is stored at 4°C or frozen at -80°C.

In addition to the above expression vector, the present invention further includes an expression vector comprising phage operator and promoter elements operatively linked to an LNFR-HKAEF92 polynucleotide, called pHE4a (ATCC Accession Number 209645, deposited February 25, 1998). This vector contains: (1) a neomycin phosphotransferase gene as a selection marker, (2) an E. coli origin of replication, (3) a T5 phage promoter sequence, (4) two lac operator sequences, (5) a Shine-Delgarno sequence, and (6) the lactose operon repressor gene (laclq). The origin of replication (oriC) is derived from pUC 19 (LTI, Gaithersburg, MD) The promoter sequence and operator sequences are made synthetically.

DNA can be inserted into the pHEa by restricting the vector with Nde I and Xba I, Bam HI, Xho 1, or Asp 718, running the restricted product on a gel, and isolating the larger fragment (the stuffer fragment should be about 310 base pairs). The DNA insert is generated according to the PCR protocol described in Example 1. using PCR primers which encode restriction sites for Nde I (5' primer) and Nde I and Xba 1, Bam HI, Xho I, or Asp 718 (3' primer). The PCR insert is gel purified and restricted with compatible enzymes. The insert and vector are ligated according to standard protocols. The engineered vector could easily be substituted in the above protocol to express protein in a bacterial system.

Example 6; Purification of INFR-HKAEF92 Polypeptide from an Inclusion Body The following alternative method can be used to purify LNFR-HKAEF92 polypeptide expressed in E coli when it is present in the form of inclusion bodies. Unless otherwise specified, all of the following steps are conducted at 4-10°C.

Upon completion of the production phase of the E. coli fermentation, the cell culture is cooled to 4-10°C and the cells harvested by continuous centrifugation at 15,000 rpm (Heraeus Sepatech). On the basis of the expected yield of protein per unit weight of cell paste and the amount of purified protein required, an appropriate amount of cell paste, by weight, is suspended in a buffer solution containing 100 mM Tris, 50 mM EDTA, pH 7.4. The cells are dispersed to a homogeneous suspension using a high shear mixer. The cells are then lysed by passing the solution through a microfluidizer (Microfuidics. Corp. or APV Gaulin. Inc.) twice at 4000-6000 psi. The homogenate is then mixed with NaCl solution to a final concentration of 0.5 M NaCl, followed by centrifugation at 7000 xg for 15 min. The resultant pellet is washed again using 0.5M NaCl, 100 mM Tris, 50 mM EDTA, pH 7.4.

The resulting washed inclusion bodies are solubilized with 1.5 M guanidine hydrochloride (GuHCl) for 2-4 hours. After 7000 x g centrifugation for 15 min., the pellet is discarded and the polypeptide containing supernatant is incubated at 4°C overnight to allow further GuHCl extraction. Following high speed centrifugation (30,000 x g) to remove insoluble particles, the GuHCl solubilized protein is refolded by quickly mixing the GuHCl extract with 20 volumes of buffer containing 50 mM sodium, pH 4.5, 150 mM NaCl, 2 mM EDTA by vigorous stirring. The refolded diluted protein solution is kept at 4°C without mixing for 12 hours prior to further purification steps. To clarify the refolded polypeptide solution, a previously prepared tangential filtration unit equipped with 0.16 μm membrane filter with appropriate surface area (e.g., Filtron), equilibrated with 40 mM sodium acetate, pH 6.0 is employed. The filtered sample is loaded onto a cation exchange resin (e.g., Poros HS-50, Perseptive Biosystems). The column is washed with 40 mM sodium acetate, pH 6.0 and eluted with 250 mM, 500 mM. 1000 mM. and 1500 mM NaCl in the same buffer, in a stepwise manner. The absorbance at 280 nm of the effluent is continuously monitored. Fractions are collected and further analyzed by SDS-PAGE.

Fractions containing the INFR-HKAEF92 polypeptide are then pooled and mixed with 4 volumes of water. The diluted sample is then loaded onto a previously prepared set of tandem columns of strong anion (Poros HQ-50. Perseptive

Biosystems) and weak anion (Poros CM-20, Perseptive Biosystems) exchange resins. The columns are equilibrated with 40 mM sodium acetate, pH 6.0. Both columns are washed with 40 mM sodium acetate, pH 6.0. 200 mM NaCl. The CM-20 column is then eluted using a 10 column volume linear gradient ranging from 0.2 M NaCl, 50 mM sodium acetate, pH 6.0 to 1.0 M NaCl, 50 mM sodium acetate. pH 6.5. Fractions are collected under constant A₂₈₀ monitoring of the effluent. Fractions containing the polypeptide (determined, for instance, by 16% SDS-PAGE) are then pooled. The resultant LNFR-HKAEF92 polypeptide should exhibit greater than 95% purity after the above refolding and purification steps. No major contaminant bands should be observed from Commassie blue stained 16% SDS-PAGE gel when 5 μg of purified protein is loaded. The purified INFR- HKAEF92 protein can also be tested for endotoxin LPS contamination, and typically the LPS content is less than 0. 1 ng ml according to LAL assays.

Example 7: Cloning and Expression of INFR-HKA-EF92 in a Baculovirus Expression System In this example, the plasmid shuttle vector pA2 is used to insert LNFR-

HKAEF92 polynucleotide into a baculovirus to express LNFR-HKAEF92. This expression vector contains the strong polyhedrin promoter of the Autographa calif ornica nuclear polyhedrosis virus (AcMNPV) followed by convenient restriction sites such as Bam HI, Xba I and Asp 718. The polyadenylation site of the simian virus 40 ("SV40") is used for efficient polyadenylation. For easy selection of recombinant virus, the plasmid contains the beta-galactosidase gene from E. coli under control of a weak Drosophila promoter in the same orientation, followed by the polyadenylation signal of the polyhedrin gene. The inserted genes are flanked on both sides by viral sequences for cell-mediated homologous recombination with wild-type viral DNA to generate a viable virus that express the cloned LNFR-HKAEF92 polynucleotide.

Many other baculovirus vectors can be used in place of the vector above, such as pAc373, pVL941, and pAcLMl, as one skilled in the art would readily appreciate, as long as the construct provides appropriately located signals for transcription, translation, secretion and the like, including a signal peptide and an in-frame AUG as required. Such vectors are described, for instance, by Luckow and colleagues (Virology 170:31-39 (1989)).

Specifically, the LNFR-HKAEF92 cDNA sequence contained in the deposited clone, including the AUG initiation codon and any naturally associated leader sequence, is amplified using the PCR protocol described in Example 1. If the naturally occurring signal sequence is used to produce the secreted protein, the pA2 vector does not need a second signal peptide. The vector can be modified (now designated pA2GP) to include a baculovirus leader sequence, using the standard methods described by Summers and coworkers ("A Manual of Methods for Baculovirus Vectors and Insect Cell Culture Procedures," Texas Agricultural Experimental Station Bulletin No. 1555 (1987)).

More specifically, the cDNA sequence encoding the extracellular form of INFR-HKAEF92 protein in the deposited clone is amplified using PCR oligonucleotide primers corresponding to the 5' and 3' sequences of the gene. The 5' primer has the sequence

5'-GCGAGATCTGCCATCATGCAGACTTTCACAATG-3' (SEQ ID NO: 14) containing the Bgl π restriction enzyme site, an efficient signal for initiation of translation in eukaryotic cells (shown in the primer sequence in italics; Kozak, M., J. Mol Biol. 196:947-950 (1987)). The 3' primer has the sequence

5'-GCGAGATCTTCACAGGGGAATGGCCTCTCC-3' (SEQ ID NO: 15) containing the Bgl II restriction site followed by 20 nucleotides complementary to the 3' noncoding sequence in Figure 1.

The amplified fragment is isolated from a 1 % agarose gel using a commercially available kit ("Geneclean, " BIO 101 Inc., La Jolla, CA). The fragment then is digested with appropriate restriction enzymes and again purified on a 1 % agarose gel.

The plasmid is digested with the corresponding restriction enzymes and optionally, can be dephosphorylated using calf intestinal phosphatase, using routine procedures known in the art. The DNA is then isolated from a 1 % agarose gel using a commercially available kit ("Geneclean" BIO 101 Inc., La Jolla, CA).

The fragment and the dephosphorylated plasmid are ligated together with T4 DNA ligase E. coli HB101 or other suitable E. coli hosts such as XL-1 Blue (Stratagene Cloning Systems, La Jolla, CA) cells are transformed with the ligation mixture and spread on culture plates. Bacteria containing the plasmid are identified by digesting DNA from individual colonies and analyzing the digestion product by gel electrophoresis. The sequence of the cloned fragment is confirmed by DNA sequencing.

Five μg of a plasmid containing the polynucleotide is co-transfected with 1.0 μg of a commercially available linearized baculovirus DNA ("BaculoGoId™ baculovirus DNA", Pharmingen, San Diego, CA), using the lipofection method described by Feigner and colleagues {Proc. Natl. Acad. Sci. USA 84:1413-1411 (1987)). One μg of BaculoGoId™ virus DNA and 5 μg of the plasmid are mixed in a sterile well of a microtiter plate containing 50 μl of serum-free Grace's medium (Life Technologies Inc., Gaithersburg, MD). Afterwards. 10 μl Lipofectin plus 90 μl Grace's medium are added, mixed and incubated for 15 minutes at room temperature. Then the transfection mixture is added drop-wise to Sf9 insect cells (ATCC CRL 1711) seeded in a 35 mm tissue culture plate with 1 ml Grace's medium without serum. The plate is then incubated for 5 hours at 27°C. The transfection solution is then removed from the plate and 1 ml of Grace's insect medium supplemented with 10% fetal calf serum is added. Cultivation is then continued at 27°C for four days.

After four days the supernatant is collected and a plaque assay is performed, as described by Summers and Smith (supra). An agarose gel with "Blue Gal" (Life Technologies Inc., Gaithersburg) is used to allow easy identification and isolation of gal-expressing clones, which produce blue-stained plaques. (A detailed descnption of a "plaque assay" of this type can also be found in the user's guide for insect cell culture and baculovirology distributed by Life Technologies Inc., Gaithersburg, page 9-10.) After appropriate incubation, blue stained plaques are picked with the tip of a micropipettor (e.g., Eppendorf). The agar containing the recombinant viruses is then resuspended in a microcentrifuge tube containing 200 μl of Grace's medium and the suspension containing the recombinant baculovirus is used to infect Sf9 cells seeded in 35 mm dishes. Four days later the supematants of these culture dishes are harvested and then they are stored at 4°C. To verify the expression of the polypeptide, Sf 19 cells are grown in Grace's medium supplemented with 10% heat-inactivated FBS. The cells are infected with the recombinant baculovirus containing the polynucleotide at a multiplicity of infection ("MOI") of about 2. If radiolabeled proteins are desired, 6 hours later the medium is removed and is replaced with SF900 II medium minus methionine and cysteine (available from Life Technologies Inc., Rockville, MD). After 42 hours, 5 μCi of

³⁵S-methionine and 5 μCi of ³⁵S-cysteine (available from Amersham) are added. The cells are further incubated for 16 hours and then are harvested by centrifugation. The proteins in the supernatant as well as the intracellular proteins are analyzed by SDS-PAGE followed by autoradiography (if radiolabeled). Microsequencing of the amino acid sequence of the amino terminus of purified protein may be used to determine the amino terminal sequence of the produced LNFR-HKAEF92 protein.

Example 8: Expression of INFR-HKAEF92 in Mammalian Cells LNFR-HKAEF92 polypeptide can be expressed in a mammalian cell. A typical mammalian expression vector contains a promoter element, which mediates the initiation of transcription of mRNA. a protein coding sequence, and signals required for the termination of transcnption and polyadenylation of the transcript. Additional elements include enhancers, Kozak sequences and intervening sequences flanked by donor and acceptor sites for RNA splicing. Highly efficient transcription is achieved with the early and late promoters from SV40, the long terminal repeats (LTRs) from Retroviruses, e.g., RSV, HTLV-1, HTV-1 and the early promoter of the cytomegalovirus (CMV). However cellular elements can also be used (e.g., the human actin promoter).

Suitable expression vectors for use in practicing the present invention include, for example, vectors such as pS VL and pMSG (Pharmacia. Uppsala, Sweden), pRSVcat (ATCC 37152), pSV2dhfr (ATCC 37146), pBC12MI (ATCC 67109), pCMVSport 2.0, and pCMVSport 3.0. Mammalian host cells that could be used include, Hela, 293, H9 and Jurkat cells, mouse NIH3T3 and C 127 cells, Cos 1, Cos 7 and CVI, quail QC1-3 cells, mouse L cells and Chinese hamster ovary (CHO) cells. Alternatively, INFR-HKAEF92 polypeptide can be expressed in stable cell lines containing the LNFR-HKAEF92 polynucleotide integrated into a chromosome. The co-transfection with a selectable marker such as dhft, gpt, neomycin or hygromycin allows the identification and isolation of the transfected cells.

The transfected LNFR-HKAEF92 gene can also be amplified to express large amounts of the encoded protein. The DHFR (dihydrofolate reductase) marker is useful in developing cell lines that carry several hundred or even several thousand copies of the gene of interest (see. e.g., Alt, F. W., et al, J. Biol. Chem. 253:1357-1370 (1978): Hamlin, J. L. and Ma. C, Biochem. et Biophys. Acta,

1097:107-143 (1990); Page, M. J. and Sydenham, M. A.. Biotechnology 9:64-68 (199 1)). Another useful selection marker is the enzyme glutamine synthase (GS; Murphy, et al, Biochem. J. 227:277-279 (1991); Bebbington, et al, Bio/Technology 10:169-175 (1992)). Using these markers, the mammalian cells are grown in selective medium and the cells with the highest resistance are selected. These cell lines contain the amplified gene(s) integrated into a chromosome. Chinese hamster ovary (CHO) and NSO cells are often used for the production of proteins.

Derivatives of the plasmid pSV2-dhfr (ATCC Accession No. 37146), the expression vectors pC4 (ATCC Accession No. 209646) and pC6 (ATCC Accession No.209647) contain the strong promoter (LTR) of the Rous SarcomaVirus (Cullen, et al., Mol. Cell. Biol, 438-447 (March, 1985)) plus a fragment of the CMV-enhancer (Boshart. et al. Cell 41:521-530 (1985)). Multiple cloning sites, e.g., with the restriction enzyme cleavage sites Bam HI, Xba I and Asp 718, facilitate the cloning of LNFR-HKAEF92. The vectors also contain the 3' intron, the polyadenylation and termination signal of the rat preproinsulin gene, and the mouse DHFR gene under control of the SV40 early promoter.

Specifically, the plasmid pC6, for example, is digested with appropriate restriction enzymes and then dephosphorylated using calf intestinal phosphates by procedures known in the art. The vector is then isolated from a 1% agarose gel. LNFR-HKAEF92 polynucleotide is amplified according to the protocol outlined in Example 1. If the naturally occurcing signal sequence is used to produce the secreted protein, the vector does not need a second signal peptide.

Alternatively, if the naturally occurring signal sequence is not used, the vector can be modified to include a heterologous signal sequence (see, e.g., WO 96/34891). The amplified fragment is isolated from a 1 % agarose gel using a commercially available kit ("Geneclean," BIO 101 Inc., La Jolla, Ca.). The fragment then is digested with appropriate restriction enzymes and again purified on a 1% agarose gel. The amplified fragment is then digested with the same restriction enzyme and purified on a 1% agarose gel. The isolated fragment and the dephosphorylated vector are then ligated with T4 DNA ligase. E. coli HB 101 or XL-1 Blue cells are then transformed and bacteria are identified that contain the fragment inserted into plasmid pC6 using, for instance, restriction enzyme analysis. Chinese hamster ovary cells lacking an active DHFR gene is used for transfection. Five μg of the expression plasmid pC6 is cotransfected with 0.5 μg of the plasmid pSV-neo using lipofectin (Felaner, et al., supra). The plasmid pSV2-neo contains a dominant selectable marker, the neo gene from Tn5 encoding an enzyme that confers resistance to a group of antibiotics including G418. The cells are seeded in alpha minus MEM supplemented with 1 mg/ml G418. After 2 days, the cells are trypsinized and seeded in hybridoma cloning plates (Greiner, Germany) in alpha minus MEM supplemented with 10, 25, or 50 ng/ml of metothrexate plus 1 mg/ml G418. After about 10-14 days single clones are trypsinized and then seeded in 6-well petri dishes or 10 ml flasks using different concentrations of methotrexate (for example, 50 nM, 100 nM. 200 nM. 400 nM, 800 nM). Clones growing at the highest concentrations of methotrexate are then transferred to new 6-well plates containing even higher concentrations of methotrexate (1 μM, 2 μM, 5 μM, 10 mM, 20 mM). The same procedure is repeated until clones are obtained which grow at a concentration of 100-200 μM. Expression of LNFR-HKAEF92 is analyzed, for instance, by SDS-PAGE and Western blot or by reverse phase HPLC analysis.

Example 9: Protein Fusions of INFR-HKAEF92

LNFR-HKAEF92 polypeptides are preferably fused to other proteins. These fusion proteins can be used for a variety of applications. For example, fusion of INFR-HKAEF92 polypeptides to His-tag, HA-tag, protein A, IgG domains, and maltose binding protein facilitates purification (see Example 5; see also EP A 394,827; Traunecker, et al., Nature 331:84-86 (1988).) Similarly, fusion to IgG-1, IgG-3 and albumin increases the halflife time in vivo. Nuclear localization signals fused to LNFR-HKAEF92 polypeptides can target the protein to a specific subcellular localization, while covaient heterodimer or homodimers can increase or decrease the activity of a fusion protein. Fusion proteins can also create chimeric molecules having more than one function. Finally, fusion proteins can increase solubility and/or stability of the fused protein compared to the non-fused protein. All of the types of fusion proteins described above can be made by modifying the following protocol, which outlines the fusion of a polypeptide to an IgG molecule, or the protocol described in Example 5.

Briefly, the human Fc portion of the IgG molecule can be PCR amplified, using primers that span the 5' and 3 ' ends of the sequence described below. These primers also should have convenient restriction enzyme sites that will facilitate cloning into an expression vector, preferably a mammalian expression vector.

For example, if pC4 (Accession No. 209646) is used, the human Fc portion can be ligated into the Bam HI cloning site. Note that the 3' Bam HI site should be destroyed. Next, the vector containing the human Fc portion is again restricted with Bam HI, linearizing the vector, and LNFR-HKAEF92 polynucleotide, isolated by the PCR protocol described in Example 1. is ligated into this Bam HI site. Note that the polynucleotide is cloned without a stop codon, otherwise a fusion protein will not be produced. If the naturally occurring signal sequence is used to produce the secreted protein, pC4 does not need a second signal peptide. Alternatively, if the naturally occurring signal sequence is not used, the vector can be modified to include a heterologous signal sequence (see, e.g., WO96/34891).

Human IgG Fc region (SEQ ID NO:16):

GGGATCCGGAGCCCAAATCTTCTGACAAAACTCACACATGCCCACCGTG CCCAGCACCTGAATTCGAGGGTGCACCGTCAGTCTTCCTCTTCCCCCCAA AACCCAAGGACACCCTCATGATCTCCCGGACTCCTGAGGTCACATGCGT GGTGGTGGACGTAAGCC ACGAAG ACCCTGAGGTC AAGTTC AACTGGTAC GTGGACGGCGTGGAGGTGCATAATGCCAAGACAAAGCCGCGGGAGGAG CAGTACAACAGCACGTACCGTGTGGTCAGCCCTCACCGTCCTGCACCAG GACTGGCTGAATGGCAAGGAGTACAAGTGCAAGGTCTCCAACAAAGCCC TCCCAACCCCCATCGAGAAAACCATCTCCAAAGCCAAAGGGCAGCCCCG AGAACCACAGGTGTACACCCTGCCCCCATCCCGGGATGAGCTGACCAAG AACCAGGTCAGCCTGACCTGCCTGGTCAAAGGCTTCTATCCAAGCGACA TCGCCGTGGAGTGGGAGAGCAATGGGCAGCCGGAGAACAACTACAAGA CCACGCCTCCCGTGCTGGACTCCGACGGCTCCTTCTTCCTCTACAGCAAG CTCACCGTGGACAAGAGCAGGTGGCAGCAGGGGAACGTCTTCTCATGCT CCGTGATGCATGAGGCTCTGCACAACCACTACACGCAGAAGAGCCTCTC CCTGTCTCCGGGTAAATGAGTGCGACGGCCGCGACTCTAGAGGAT

Example 10; Production of an Antibody

The antibodies of the present invention can be prepared by a variety of methods (see, Current Protocols, Chapter 2). For example, cells expressing LNFR- HKAEF92 is administered to an animal to induce the production of sera containing polyclonal antibodies. In a prefened method, a preparation of LNFR-HKAEF92 protein is prepared and purified to render it substantially free of natural contaminants. Such a preparation is then introduced into an animal in order to produce polyclonal antisera of greater specific activity.

In the most preferred method, the antibodies of the present invention are monoclonal antibodies (or protein binding fragments thereof). Such monoclonal antibodies can be prepared using hybridoma technology (Kohler, et al, Nature 256:495 (1975); Kohler. et al., Ewr. J Immunol 6:511 (1976); Kohler, et al.. Eur.J Immitnol 6:292 ( 1976); Hammerling, et al., in: Monoclonal Antibodies and T-Cell Hybridomas, Elsevier, N.Y., pp. 563-681 (1981)). In general, such procedures involve immunizing an animal (preferably a mouse) with LNFR-HKAEF92 polypeptide or, more preferably, with a secreted LNFR-HKAEF92 polypeptide-expressing cell. Such cells may be cultured in any suitable tissue culture medium; however, it is preferable to culture cells in Earle's modified Eagle's medium supplemented with 10% fetal bovine serum (inactivated at about 56°C and supplemented with about 10 g/1 of nonessential amino acids, about 1,000 U/ml of penicillin, and about 100 μg/ml of streptomycin. The splenocytes of such mice are extracted and fused with a suitable myeloma cell line. Any suitable myeloma cell line may be employed in accordance with the present invention; however, it is preferable to employ the parent myeloma cell line (SP20), available from the ATCC. After fusion, the resulting hybridoma cells are selectively maintained in HAT medium, and then cloned by limiting dilution as described by Wands and colleagues (Gastroenterology 80:225-232 ( 1981)). The hybridoma cells obtained through such a selection are then assayed to identify clones which secrete antibodies capable of binding the LNFR-HKAEF92 polypeptide.

Alternatively, additional antibodies capable of binding to LNFR-HKAEF92 polypeptide can be produced in a two-step procedure using anti-idiotypic antibodies. Such a method makes use of the fact that antibodies are themselves antigens, and therefore, it is possible to obtain an antibody which binds to a second antibody. In accordance with this method, protein specific antibodies are used to immunize an animal, preferably a mouse. The splenocytes of such an animal are then used to produce hybridoma cells, and the hybridoma cells are screened to identify clones which produce an antibody whose ability to bind to the LNFR-HKAEF92 protein-specific antibody can be blocked by LNFR-HKAEF92. Such antibodies comprise anti-idiotypic antibodies to the INFR-HKAEF92 protein-specific antibody and can be used to immunize an animal to induce formation of further LNFR-HKAEF92 protein-specific antibodies. It will be appreciated that Fab and F(ab')2 and other fragments of the antibodies of the present invention may be used according to the methods disclosed herein. Such fragments are typically produced by proteolytic cleavage, using enzymes such as papain (to produce Fab fragments) or pepsin (to produce F(ab')2 fragments). Alternatively, secreted LNFR-HKAEF92 protein-binding fragments can be produced through the application of recombinant DNA technology or through synthetic chemistry.

For in vivo use of antibodies in humans, it may be preferable to use "humanized" chimeric monoclonal antibodies. Such antibodies can be produced using genetic constructs derived from hybridoma cells producing the monoclonal antibodies described above. Methods for producing chimeric antibodies are known in the art (see, for review, Morrison, Science 229:1202 (1985); Oi, et al, BioTechniques 4:214 (1986); Cabilly, et al., U.S. Patent No. 4,816,567; Taniguchi, et al., EP 171496; Monison, et al.. EP 173494; Neuberger, et al, WO 8601533; Robinson, et al, WO 8702671; Boulianne. et al. Nature 312:643 ) (1984); Neuberger, et al., Nature 314:268 (1985)).

Example 11: Production Of IΝFR-HKNEF92 Protein For High-Throughput Screening Assays The following protocol produces a supernatant containing LΝFR-HKAEF92 polypeptide to be tested. This supernatant can then be used in the screening assays described subsequently in Examples 13-20.

First, dilute poly-D-lysine (644 587 Boehringer-Mannheim) stock solution (1 mg/ml in PBS) 1:20 in PBS (Phosphate Buffered Saline; w/o calcium or magnesium 17-516F Biowhittaker) for a working solution of 50 μg/ml. Add 200 μl of this solution to each well (24 well plates) and incubate at RT for 20 minutes. Be sure to distribute the solution over each well (note: a 12-channel pipetter may be used with tips on every other channel). Aspirate the poly-D-lysine solution and rinse with 1 ml PBS. The PBS should remain in the well until just prior to plating the cells and plates may be poly-lysine coated in advance for up to two weeks.

Plate 293 T cells (do not carry cells past P+20) at 2 x 10⁵ cells/well in 0.5 ml DMEM (Dulbecco's Modified Eagle Medium) supplemented with 4.5 G/L glucose, L-glutamine (12-604F Biowhittaker)), 10% heat inactivated FBS (14-503F Biowhittaker), and lx Penstrep (17-602E Biowhittaker). Let the cells grow overnight. Following overnight incubation, mix together in a sterile solution basin: 300 μl Lipofectamine (18324-012 Gibco/BRL) and 5ml Optimem I (31985070 Gibco/BRL) in each well of a 96-well plate. With a small volume multi-channel pipetter, aliquot approximately 2 μg of an expression vector containing a polynucleotide insert, produced by the methods described in Examples 8 or 9, into an appropriately labeled 96-well round bottom plate. With a multi-channel pipetter. add 50 μl of the Lipofectamine/Optimem I mixture to each well. Pipette up and down gently to mix. Incubate at RT for 15-45 minutes. After about 20 minutes, use a multi-channel pipetter to add 150 μl Optimem I to each well. As a control, one plate of vector DNA lacking an insert should be transfected with each set of transfections. Preferably, the transfection should be performed by simultaneously performing the following tasks in a staggered fashion. Thus, hands-on time is cut in half, and the cells are not excessively incubated in PBS. First, person A aspirates the media from four 24-well plates of cells, and then person B rinses each well with 0.5-lml PBS. Person A then aspirates the PBS rinse, and person B, using a 12-channel pipetter with tips on every other channel, adds the 200 μl of DNA/Lipofectamine/Optimem I complex to the odd wells first, then to the even wells, to each row on the 24-well plates. Plates are then incubated at 37°C for 6 hours.

While cells are incubating, the appropriate media is prepared: either 1 % BSA in DMEM with 1 x penstrep, or HGS CHO-5 media (116.6 mg/L of CaCl₂ (anhyd): 0.00130 mg/L CuSO₄-5H₂O; 0.050 mg/L of Fe(N0₃)₃-9H₂O; 0.417 mg/L of FeSO₄-7H₂O; 311.80 mg/L of KC1; 28.64 mg/L of MgCl₂; 48.84 mg/L of MgSO₄; 6995.50 mg/L of NaCl; 2400.0 mg/L of NaHCO₃; 62.50 mg/L of NaH₂PO₄-H₂0; 71.02 mg/L of Na₂HP0₄; .4320 mg/L of ZnS0₄-7H,0: .002 mg/L of Arachidonic Acid; 1.022 mg/L of Cholesterol; 0.070 mg/L of D-L-alpha-Tocopherol-Acetate; 0.0520 mg/L of Linoleic Acid: 0.010 mg/L of Linolenic Acid; 0.010 mg/L of Myristic Acid; 0.010 mg/L of Oleic Acid: 0.010 mg/L of Palmitric Acid; 0.010 mg/L of Palmitic Acid; 100 mg/L of Pluronic F-68; 0.010 mg/L of Stearic Acid; 2.20 mg/L of Tween 80; 4551 mg/L of D-Glucose; 130.85 mg/ml of L- Alanine; 147.50 mg/ml of L-Arginine-HCL; 7.50 mg/ml of L-Asparagine-H-,0; 6.65 mg ml of L-Aspartic Acid; 29.56 mg/ml of L-Cystine-2HCL-H₂0; 31.29 mg/ml of L-Cystine-2HC1; 7.35 mg/ml of L-Glutamic Acid; 365.0 mg/ml of L-Glutamine; 18.75 mg/ml of Glycine; 52.48 mg/ml of L-Histidine-HCL-H₂0; 106.97 mg/ml of L-Isoleucine; 111.45 mg/ml of L-Leucine; 163.75 mg/ml of L-Lysine HCL; 32.34 mg/ml of L-Methionine; 68.48 mg/ml of L-Phenylalainine; 40.0 mg/ml of L-Proline; 26.25 mg/ml of L-Serine; 101.05 mg/ml of L-Threonine: 19.22 mg/ml of L-Tryptophan; 91.79 mg/ml of L-Tryrosine-2Na-2H₂0; and 99.65 mg/ml of L-Valine; 0.0035 mg/L of Biotin 3.24 mg/L of D-Ca Pantothenate; 11.78 mg/L of Choline Chloride; 4.65 mg/L of Folic Acid; 15.60 mg/L of i-Inositol: 3.02 mg/L of Niacinamide: 3.00 mg/L of Pyridoxal HCL; 0.031 mg/L of Pyridoxine HCL; 0.319 mg/L of Riboflavin; 3.17 mg/L of Thiamine HCL; 0.365 mg/L of Thymidine; 0.680 mg/L of Vitamin B_]2; 25 mM of HEPES Buffer; 2.39 mg/L of Na Hypoxanthine; 0.105 mg/L of Lipoic Acid; 0.081 mg/L of Sodium Putrescine-2HCL; 55.0 mg/L of Sodium Pyruvate; 0.0067 mg/L of Sodium Selenite; 20uM of Ethanoiamine; 0. 122 mg/L of Ferric Citrate; 41.70 mg/L of Methyl-B-Cyclodextrin complexed with Linoleic Acid; 33.33 mg/L of Methyl-B- Cyclodextrin complexed with Oleic Acid; 10 mg/L of Methyl-B-Cyclodextrin complexed with Retinal Acetate. Adjust osmolarity to 327 mOsm) with 2mm glutamine and lx penstrep. (BSA (81-068-3 Bayer) lOOgm dissolved in 1L DMEM for a 10% BSA stock solution). Filter the media and collect 50 μl for endotoxin assay in 15ml polystyrene conical.

The transfection reaction is terminated, again, preferably by two people, at the end of the incubation period. Person A aspirates the transfection media, while person B adds 1.5 ml of the appropriate media to each well. Incubate at 37°C for 45 or 72 hours, depending on the media used (1% BSA for 45 hours or CHO-5 for 72 hours).

On day four, using a 300 μl multichannel pipetter, aliquot 600 μl in one 1ml deep well plate and the remaining supernatant into a 2 ml deep well. The supernatant from each well can then be used in the assays described in Examples 13-20. It is specifically understood that when activity is obtained in any of the assays described below using a supernatant, the activity originates from either the INFR-HKAEF92 polypeptide directly (e.g., as a secreted protein) or by LNFR- HKAEF92 inducing expression of other proteins, which are then secreted into the supernatant. Thus, the invention further provides a method of identifying the protein in the supernatant characterized by an activity in a particular assay.

Example 12: Construction of GAS Reporter Construct

One signal transduction pathway involved in the differentiation and proliferation of cells is called the Jaks-STATs pathway. Activated proteins in the Jaks-STATs pathway bind to gamma activation site ("GAS") elements or interferon-sensitive responsive element ("ISRE"), located in the promoter of many genes. The binding of a protein to these elements alter the expression of the associated gene. GAS and ISRE elements are recognized by a class of transcription factors called Signal Transducers and Activators of Transcription, or "STATs." There are six members of the STATs family. Statl and Stat3 are present in many cell types, as is Stat2 (as response to LFN-alpha is widespread). Stat4 is more restricted and is not in many cell types though it has been found in T-helper class I. cells after treatment with LL-12. Stat5 was originally called mammary growth factor, but has been found at higher concentrations in other cells including myeloid cells. It can be activated in tissue culture cells by many cytokines.

The STATs are activated to translocate from the cytoplasm to the nucleus upon tyrosine phosphorylation by a set of kinases known as the Janus Kinase ("Jaks") family. Jaks represent a distinct family of soluble tyrosine kinases and include Tyk2, Jakl, Jak2. and Jak3. These kinases display significant sequence similarity and are generally catalytically inactive in resting cells.

The Jaks are activated by a wide range of receptors summarized in the Table below (adapted from review by Schidler and Damell, Ann. Rev. Biochem. 64:621-51 (1995))). A cytokine receptor family, capable of activating Jaks, is divided into two groups: (a) Class 1 includes receptors for LL-2, LL-3, LL-4, LL-6, LL-7, LL-9, LL-11, IL-12, LL-15, Epo, PRL, GH. G-CSF, GM-CSF, LLF, CNTF, and thrombopoietin; and (b) Class 2 includes LFN-a, LFN-g, and IL-10. The Class 1 receptors share a conserved cysteine motif (a set of four conserved cysteines and one tryptophan) and a WSXWS motif (a membrane proximal region encoding Trp-Ser-Xxx-Trp-Ser (where "Xxx" represents any amino acid)).

Thus, on binding of a ligand to a receptor, Jaks are activated, which in turn activate STATs, which then translocate and bind to GAS elements. This entire process is encompassed in the Jaks-STATs signal transduction pathway.

Therefore, activation of the Jaks-STATs pathway, reflected by the binding of the GAS or the ISRE element, can be used to indicate proteins involved in the proliferation and differentiation of cells. For example, growth factors and cytokines are known to activate the Jaks-STATs pathway (see Table below). Thus, by using GAS elements linked to reporter molecules, activators of the Jaks-STATs pathway can be identified.

JAKs STATS

GAS (elements) or ISRE Ligand tyk2 Jakl Jak2 Jak3

IFN family

IFN-a/B + + - - 1,2,3 ISRE IFN-g + + - 1 GAS (IRFl>Lys6>IFP)

11-10 + ? ? - 1,3

gp!30 family LL-6 (Pleiotrophic) + + + "^> 1,3 GAS (IRFl>Lys6>IFP)

II- 11 (Pleiotrophic) ? + ? ? 1,3

OnM(Pleiotrophic) ? + + ? 1,3

LIF(Pleiotrophic) ? + + ? 1.3 CNTF(Pleiotrophic) -/+ + + ? 1,3

G-CSF(Pleiotrophic) ? + ? ? 1,3

LL-12(Pleiotrophic) + - + + 1,3

g-C family LL-2 (lymphocytes) - + - + 1,3,5 GAS

LL-4 (lymph/myeloid) + - + 6 GAS (IRF1

IFP »Ly6)(IgH)

IL-7 (lymphocytes) - + - + 5 GAS

LL-9 (lymphocytes) + - + 5 GAS LL-13 (lymphocyte) - + ? ? 6 GAS

LL-15 ? + ? + 5 GAS

gp!40 family

LL-3 (myeloid) + - 5 GAS (IRFl>LFP»Ly6)

LL-5 (myeloid) + - 5 GAS

GM-CSF (myeloid) - - + - 5 GAS

Growth hormone family GH 0 - + 5

PRL 0 +/- + 1.3,5

EPO 9 - + 5

GAS(B-CAS>IRFl=LFP»Ly6)

Receptor Tyrosine Kinases EGF ? 1,3 GAS (IRF1)

PDGF + 1,3 CSF-1 + 1,3 GAS (not IRF1)

To construct a synthetic GAS containing promoter element, which is used in the biological assays described in Examples 13-14, a PCR based strategy is employed to generate a GAS-SV40 promoter sequence. The 5' primer contains four tandem copies of the GAS -binding site found in the LRF 1 promoter and previously demonstrated to bind STATs upon induction with a range of cytokines (Rothman, et al, Immunity 1:457-468 (1994)). although other GAS or ISRE elements can be used instead. The 5' primer also contains 18 bp of sequence complementary to the SV40 early promoter sequence and is flanked with an Xho I restriction site. The sequence of the 5 primer is: 5'-GCG CCT CGA GAT TTC CCC GAA ATC TAG ATT TCC CCG AAA TGA TTT CCC CGA AAT GAT TTC CCC GAA ATA TCT GCC ATC TCA ATT AG-3' (SEQ ID NO: 18).

The downstream primer is complementary to the SV40 promoter and is flanked with a Hin dHI site: 5'-GCG GCA AGC TTT TTG CAA AGC CTA GGC-3' (SEQ ID NO: 19).

PCR amplification is performed using the SV40 promoter template present in the B-gal:promoter plasmid obtained from Clontech. The resulting PCR fragment is digested with Xho I and Hin dill and subcloned into BLSK2-(Stratagene). Sequencing with forward and reverse primers confirms that the insert contains the following sequence:

CTCGAGATTTCCCCGAAATCTAGATTTCCCCGAAATGATTTCCCCGAAAT GATTTCCCCGAANTATCTGCCATCTCAATTAGTCAGCAACCATAGTCCCG CCCCTAACTCCGCCCATCCCGCCCCTAACTCCGCCCAGTTCCGCCCATTC TCCGCCCCATGGCTGACTAATTTTTTTTATTTATGCAGAGGCCGAGGCCG CCTCGGCCTCTGAGCTATTCCAGAAGTAGTGAGGAGGCTTTTTTGGAGG CCTAGGCTTTTGCAAAAAGCTT (SEQ ID NO:20).

With this GAS promoter element linked to the SV40 promoter, a GAS:SEAP2 reporter construct is next engineered. Here, the reporter molecule is a secreted alkaline phosphatase, or "SEAP", Clearly, however, any reporter molecule can be instead of SEAP, in this or in any of the other Examples. Well known reporter molecules that can be used instead of SEAP include chloramphenicol acetyltransferase (CAT), luciferase, alkaline phosphatase, B-galactosidase, green fluorescent protein (GFP), or any protein detectable by an antibody.

The above sequence confirmed synthetic GAS-SV40 promoter element is subcloned into the pSEAP-Promoter vector obtained from Clontech using Hin dill andZ/201, effectively replacing the SV40 promoter with the amplified GAS: SV40 promoter element, to create the GAS-SEAP vector. However, this vector does not contain a neomycin resistance gene, and therefore, is not preferred for mammalian expression systems.

Thus, in order to generate mammalian stable cell lines expressing the GAS-SEAP reporter, the GAS-SEAP cassette is removed from the GAS-SEAP vector using Sal I and Not I, and inserted into a backbone vector containing the neomycin resistance gene, such as pGFP-1 (Clontech), using these restriction sites in the multiple cloning site, to create the GAS-SEAP/Neo vector. Once this vector is transfected into mammalian cells, this vector can then be used as a reporter molecule for GAS binding as described in Examples 13-14.

Other constructs can be made using the above description and replacing GAS with a different promoter sequence. For example, construction of reporter molecules containing NF-kB and EGR promoter sequences are described in Examples 15 and 16. However, many other promoters can be substituted using the protocols described in these Examples. For instance, SRE, LL-2, NFAT, or Osteocalcin promoters can be substituted, alone or in combination (e.g., GAS/NF-KB/EGR, GAS/NF-KB, I1-2/NFAT, or NF-KB/GAS). Similarly, other cell lines can be used to test reporter construct activity, such as HeLa (epithelial), HUVEC (endothelial), Reh (B-cell), Saos-2 (osteoblast), HUVAC (aortic), or Cardiomyocyte. Example 13: High-Throughput Screening Assay for T-cell Activity

The following protocol is used to assess T-cell activity of LNFR-HKAEF92 by determining whether LNFR-HKAEF92 supernatant proliferates and/or differentiates T-cells. T-cell activity is assessed using the GAS/SEAP/Neo construct produced in Example 12. Thus, factors that increase SEAP activity indicate the ability to activate the Jaks-STATS signal transduction pathway. The T-cell used in this assay is Jurkat T-cells (ATCC Accession No. TLB- 152), although Molt-3 cells (ATCC Accession No. CRL-1552) and Molt-4 cells (ATCC Accession No. CRL-1582) cells can also be used. Jurkat T-cells are lymphoblastic CD4+ Th 1 helper cells. In order to generate stable cell lines, approximately 2 million Jurkat cells are transfected with the GAS-SEAP/neo vector using DMRIE-C (Life Technologies; transfection procedure described below). The transfected cells are seeded to a density of approximately 20,000 cells per well and transfectants resistant to 1 mg/ml genticin selected. Resistant colonies are expanded and then tested for their response to increasing concentrations of interferon gamma. The dose response of a selected clone is demonstrated.

Specifically, the following protocol will yield sufficient cells for 75 wells containing 200 μl of cells. Thus, it is either scaled up, or performed in multiple to generate sufficient cells for multiple 96 well plates. Jurkat cells are maintained in RPMI + 10% serum with 1% Pen-Strep. Combine 2.5 mis of OPTI-MEM (Life Technologies) with 10 μg of plasmid DNA in a T25 flask. Add 2.5 ml OPTI-MEM containing 50 μl of DMRLE-C and incubate at room temperature for 15-45 min.

During the incubation period, count cell concentration, spin down the required number of cells ( 10⁷ per transfection), and resuspended in OPTI-MEM to a final concentration of 10⁷ cells/ml. Then add 1 ml of 1 x 10⁷ cells in OPTI-MEM to T25 flask and incubate at 37°C for 6 hrs. After the incubation, add 10 ml of RPMI + 15% serum.

The Jurkat:GAS-SEAP stable reporter lines are maintained in RPMI + 10% serum, 1 mg/ml Genticin, and 1 % Pen-Strep. These cells are treated with supematants containing LNFR-HKAEF92 polypeptides or LNFR-HKAEF92 induced polypeptides as produced by the protocol described in Example 11.

On the day of treatment with the supernatant, the cells should be washed and resuspended in fresh RPMI + 10% serum to a density of 500,000 cells per ml. The exact number of cells required will depend on the number of supematants being screened. For one 96 well plate, approximately 10 million cells (for 10 plates. 100 million cells) are required.

Transfer the cells to a triangular reservoir boat, in order to dispense the cells into a 96 well dish, using a 12 channel pipette. Using a 12 channel pipette, transfer 200 μl of cells into each well (therefore adding 100,000 cells per well).

After all the plates have been seeded, 50 μl of the supematants are transferred directly from the 96 well plate containing the supematants into each well using a 12 channel pipette. In addition, a dose of exogenous interferon gamma (0.1, 1.0, 10 ng) is added to wells H9, H10, and HI 1 to serve as additional positive controls for the assay.

The 96 well dishes containing Jurkat cells treated with supematants are placed in an incubator for 48 hrs (note: this time is variable between 48-72 hrs). 35 μl samples from each well are then transferced to an opaque 96 well plate using a 12 channel pipette. The opaque plates should be covered (using sellophene covers) and stored at -20°C until SEAP assays are performed according to Example 17. The plates containing the remaining treated cells are placed at 4°C and serve as a source of material for repeating the assay on a specific well if desired.

As a positive control, 100 Unit/ml interferon gamma can be used which is known to activate Jurkat T cells. Over 30 fold induction is typically observed in the positive control wells.

Example 14: High-Throughput Screening Assay Identifying Myeloid Activity The following protocol is used to assess myeloid activity of LNFR-

HKAEF92 by determining whether INFR-HKAEF92 proliferates and/or differentiates myeloid cells. Myeloid cell activity is assessed using the GAS/SEAP/Neo construct produced in Example 12. Thus, factors that increase SEAP activity indicate the ability to activate the Jaks-STATS signal transduction pathway. The myeloid cell used in this assay is U937. a pre-monocyte cell line, although TF-1, HL60, or KG1 can be used.

To transiently transfect U937 cells with the GAS/SEAP/Neo construct produced in Example 12. a DEAE-Dextran method (Kharbanda, et. al Cell Growth & Differentiation, 5:259-265 ( 1994)) is used. First, harvest 2xl0⁷ U937 cells and wash with PBS. The U937 cells are usually grown in RPMI 1640 medium containing 10% heat-inactivated fetal bovine serum (FBS) supplemented with 100 units/ml penicillin and 100 mg/ml streptomycin.

Next, suspend the cells in 1 ml of 20 mM Tris-HCl (pH 7.4) buffer containing 0.5 mg/ml DEAE-Dextran, 8 μg GAS-SEAP2 plasmid DNA, 140 mM NaCl, 5 mM KC1 , 375 uM Na,HP0₄7H₂O, 1 mM MgCl₂, and 675 uM CaC12. Incubate at 37°C for 45 min.

Wash the cells with RPMI 1640 medium containing 10% FBS and then resuspend in 10 ml complete medium and incubate at 37°C for 36 hr. The GAS-SEAP/U937 stable cells are obtained by growing the cells in 400 μg/ml G418. The G418-free medium is used for routine growth but every one to two months, the cells should be re-grown in 400 ug/ml G418 for couple of passages.

These cells are tested by harvesting 1x10^s cells (this is enough for ten 96-well plates assay) and wash with PBS. Suspend the cells in 200 ml above described growth medium, with a final density of 5xl0⁵ cells/ml. Plate 200 μl cells per well in the 96-well plate (or lx20⁵ cells/well).

Add 50 μl of the supernatant prepared by the protocol described in Example 1 1. Incubate at 37°C for 48 to 72 hr. As a positive control. 100 U/ml interferon gamma can be used which is known to activate U937 cells. Over 30-fold induction is typically observed in the positive control wells. SEAP assay the supernatant according to the protocol described in Example 17.

Example 15: High-Throughput Screening Assay Identifying Neuronal Activity When cells undergo differentiation and proliferation, a group of genes are activated through many different signal transduction pathways. One of these genes, EGR1 (early growth response gene 1), is induced in various tissues and cell types upon activation. The promoter of EGR1 is responsible for such induction. Using the EGR1 promoter linked to reporter molecules, activation of cells can be assessed by INFR-HKAEF92.

Particularly, the following protocol is used to assess neuronal activity in PC 12 cell lines. PC 12 cells (rat phenochromocytoma cells) are known to proliferate and/or differentiate by activation with a number of mitogens, such as TPA (tetradecanoyl phorbol acetate), NGF (nerve growth factor), and EGF (epidermal growth factor). The EGR1 gene expression is activated during this treatment. Thus, by stably transfecting PC 12 cells with a construct containing an EGR promoter linked to SEAP reporter, activation of PC 12 cells by INFR-HKAEF92 can be assessed. The EGR/SEAP reporter construct can be assembled by the following protocol. The EGR-1 promoter sequence (nucleotides -633 to +1; Sakamoto, K., et al, Oncogene 6:867-871 (1991)) can be PCR amplified from human genomic DNA using the following primers: (A) 5' Primer: 5'-GCG CTC GAG GGA TGA CAG CGA TAG AAC CCC GG-3' (SEQ ID NO:21) and (B) 3' Primer: 5'-GCG AAG CTT CGC GAC TCC CCG GAT CCG CCT C-3' (SEQ ID NO:22).

Using the GAS: SEAP/Neo vector produced in Example 12. EGR1 amplified product can then be inserted into this vector. Linearize the GAS: SEAP/Neo vector using restriction enzymes Xho I and Hin dill, removing the GAS/SV40 stuffer fragment. Digest the EGR1 amplified product with the same enzymes. Ligate the vector and the EGR1 promoter.

To prepare 96 well-plates for cell culture, 2 ml of a coating solution (1:30 dilution of collagen type I (Upstate Biotech Inc. Cat#08-115) in 30% ethanol (filter sterilized)) is added per one 10 cm plate or 50 ml per well of the 96-well plate, and allowed to air dry for 2 hr. PC 12 cells are routinely grown in RPMI- 1640 medium (Bio Whittaker) containing 10% horse serum (JRH BIOSCIENCES. Cat.#12449-78P), 5% heat-inactivated fetal bovine serum (FBS) supplemented with 100 units/ml penicillin and 100 μg/ml streptomycin on a precoated 10 cm tissue culture dish. A 1:4 split is done every three to four days. Cells are removed from the plates by scraping and resuspended with pipetting up and down for more than 15 times.

Transfect the EGR/SEAP/Neo construct into PC 12 using the Lipofectamine protocol described in Example 11. EGR-SEAP/PC12 stable cells are obtained by growing the cells in 300 μg/ml G418. The G418-free medium is used for routine growth but every one to two months, the cells should be re-grown in 300 μg/ml G418 for several passages.

To assay for neuronal activity, a 10 cm plate with cells around 70 to 80% confluent is screened by removing the old medium. Wash the cells once with PBS. Then starve the cells in low serum medium (RPMI- 1640 containing 1% horse serum and 0.5% FBS with antibiotics) overnight. The next morning, remove the medium and wash the cells with PBS. Scrape off the cells from the plate, suspend the cells well in 2 ml low serum medium. Count the cell number and add more low serum medium to reach final cell density as 5xl0⁵ cells/ml. Add 200 μl of the cell suspension to each well of 96-well plate (equivalent to lxlO⁵ cells/well). Add 50 μl supernatant produced by Example 11, 37°C for 48 to 72 hr. As a positive control, a growth factor known to activate PC12 cells through EGR can be used, such as 50 ng/gl of Neuronal Growth Factor (NGF). Over fifty-fold induction of SEAP is typically seen in the positive control wells. SEAP assay the supernatant according to Example 17.

Example 16: High-Throughput Screening Assay for T-cell Activity

NF-kB (Nuclear Factor kB) is a transcription factor activated by a wide variety of agents including the inflammatory cytokines LL-1 and TNF, CD30 and CD40, lymphotoxin-a and lymphotoxin-b, by exposure to LPS or thrombin, and by expression of certain viral gene products. As a transcription factor, NF-kB regulates the expression of genes involved in immune cell activation, control of apoptosis (NF- kB appears to shield cells from apoptosis), B- and T-cell development, anti-viral and antimicrobial responses, and multiple stress responses. In non-stimulated conditions, NF- kB is retained in the cytoplasm with I-kB

(Inhibitor kB). However upon stimulation. I- kB is phosphorylated and degraded, causing NF- kB to shuttle to the nucleus, thereby activating transcription of target genes. Target genes activated by NF- kB include LL-2, LL-6, GM-CSF, ICAM-1 and class 1 MHC. Due to its central role and ability to respond to a range of stimuli, reporter constructs utilizing the NF-kB promoter element are used to screen the supematants produced in Example 1 1. Activators or inhibitors of NF-kB would be useful in treating diseases. For example, inhibitors of NF-kB could be used to treat those diseases related to the acute or chronic activation of NF-kB, such as rheumatoid arthritis.

To construct a vector containing the NF-kB promoter element, a PCR based strategy is employed. The upstream primer contains four tandem copies of the NF-kB binding site (5'-GGG GAC TTT CCC-3'; SEQ ID NO:20), 18 bp of sequence complementary to the 5' end of the SV40 early promoter sequence, and is flanked with an Xho I site: 5 -GCG GCC TCG AGG GGA CTT TCC CGG GGA

CTT TCC GGG GAC TTT CCG GGA CTT TCC ATC CTG CCA TCT CAA TTA

G-3' (SEQ ID NO:.24).

The downstream primer is complementary to the 3' end of the SV40 promoter and is flanked with a Hin dm site: 5 -GCG GCA AGC TTT TTG CAA AGC CTA

GGC-3' (SEQ ID NO:25).

PCR amplification is performed using the SV40 promoter template present in the pB-gal:promoter plasmid obtained from Clontech. The resulting PCR fragment is digested with Xho I and Hin dill and subcloned into BLSK2-(Stratagene). Sequencing with the T7 and T3 primers confirms the insert contains the following sequence:

5'-CTCGAGGGGACTTTCCCGGGGACTTTCCGGGGACTTTCCGGGACTTT

CCATCTGCCATCTCAATTAGTCAGCAACCATAGTCCCGCCCCTAACTCCG

CCCATCCCGCCCCTAACTCCGCCCAGTTCCGCCCATTCTCCGCCCCATG GCTGACTAATTTTTTTTATTTATGCAGAGGCCGAGGCCGCCTCGGCCTCT

GAGCTATTCCAGAAGTAGTGAGGAGGCTTTTTTGGAG

GCCTAGGCTTTTGCAAAAAGCTT-3' (SEQ LD NO:26)

Next, replace the SV40 minimal promoter element present in the pSEAP2-promoter plasmid (Clontech) with this NF-kB/SV40 fragment using Xho I and Hin dm. However, this vector does not contain a neomycin resistance gene, and therefore, is not preferred for mammalian expression systems.

In order to generate stable mammalian cell lines, the NF-kB/SV40/SEAP cassette is removed from the above NF-kB/SEAP vector using restriction enzymes

Sal I and Not I, and inserted into a vector containing neomycin resistance. Particularly, the ΝF-kB/SV40/SEAP cassette was inserted into pGFP- 1 (Clontech), replacing the GFP gene, after restricting pGFP- 1 with Sal I and Not I

Once NF-kB/SV40/SEAP/Neo vector is created, stable Jurkat T-cells are created and maintained according to the protocol described in Example 13. Similarly, the method for assaying supematants with these stable Jurkat T-cells is also described in. Example 13. As a positive control, exogenous TNF-a (0. 1, 1, 10 ng) is added to wells H9, H10, and HI 1 with a 5-10 fold activation typically observed.

Example 17: Assay for SEAP Activity As a reporter molecule for the assays described in Examples 13-16, SEAP activity is assayed using the Tropix Phospho-light Kit (Cat. BP-400) according to the following general procedure. The Tropix Phospho-light Kit supplies the Dilution, Assay, and Reaction Buffers used below. Prime a dispenser with the 2.5x Dilution Buffer and dispense 15 μl of 2.5x dilution buffer into Optiplates containing 35 μl of a supernatant. Seal the plates with a plastic sealer and incubate at 65°C for 30 min. Separate the Optiplates to avoid uneven heating.

Cool the samples to room temperature for 15 minutes. Empty the dispenser and prime with the Assay Buffer. Add 50 μl Assay Buffer and incubate at room temperature 5 min. Empty the dispenser and prime with the Reaction Buffer (see the table below). Add 50 μl Reaction Buffer and incubate at room temperature for 20 minutes. Since the intensity of the chemiluminescent signal is time dependent, and it takes about 10 minutes to read 5 plates on luminometer, one should treat 5 plates at each time and start the second set 10 minutes later.

Read the relative light unit in the luminometer. Set H 12 as blank, and print the results. An increase in chemiluminescence indicates reporter activity.

Reaction Buffer Formulation:

# of plates Rxn buffer diluent (ml) CSPD (ml)

10 60 3

11 65 3.25

12 70 3.5

13 75 3.75

14 80 4

15 85 4.25

16 90 4.5

17 95 4.75

18 100 5

19 105 5.25

20 110 5.5

21 115 5.75

22 120 6 23 125 6.25

24 130 6.5

25 135 6.75

26 140 7

27 145 7.25

28 150 7.5

29 155 7.75

30 160 8

31 165 8.25 3 322 1 17700 8.5

33 175 8.75

34 180 9

35 185 9.25

36 190 9.5 3 377 1 19955 9.75

38 200 10

39 205 10.25

40 210 10.5

41 215 10.75 4 422 2 22200 11

43 225 11.25

44 230 11.5

45 235 1 1.75

46 240 12 4 477 2 24455 12.25

48 250 12.5

49 255 12.75

50 260 13

Example 18: High-Throughput Screening Assay Identifying Changes in Small Molecule Concentration and Membrane Permeability

Binding of a ligand to a receptor is known to alter intracellular levels of small molecules, such as calcium, potassium, sodium, and pH, as well as alter membrane potential. These alterations can be measured in an assay to identify supematants which bind to receptors of a particular cell. Although the following protocol describes an assay for calcium, this protocol can easily be modified to detect changes in potassium, sodium, pH. membrane potential, or any other small molecule which is detectable by a fluorescent probe. The following assay uses Fluorometric Imaging Plate Reader ("FLLPR") to measure changes in fluorescent molecules (Molecular Probes) that bind small molecules. Clearly, any fluorescent molecule detecting a small molecule can be used instead of the calcium fluorescent molecule, fluo-3. used here.

For adherent cells, seed the cells at 10,000-20,000 cells/well in a Co-star black 96-well plate with clear bottom. The plate is incubated in a CO₂ incubator for 20 hours. The adherent cells are washed two times in Biotek washer with 200μl of HBSS (Hank's Balanced Salt Solution) leaving 100 ul of buffer after the final wash. A stock solution of 1 mg/ml fluo-3 is made in 10% pluronic acid DMSO. To load the cells with fluo-3, 50 ul of 12 gg/ml fluo-3 is added to each well. The plate is incubated at 37°C in a CO., incubator for 60 min. The plate is washed four times in the Biotek washer with HBSS leaving 100 μl of buffer.

For non-adherent cells, the cells are spun down from culture media. Cells are re-suspended to 2-5xl0⁶ cells/ml with HBSS in a 50-ml conical tube. Four μl of 1 mg/ml fluo-3 solution in 10% pluronic acid DMSO is added to each 1 ml of cell suspension. The tube is then placed in a 37°C water bath for 30-60 min. The cells are washed twice with HBSS, resuspended to lxlO⁶ cells/ml. and dispensed into a microplate. 100 μl/well. The plate is centrifuged at 1000 rpm for 5 min. The plate is then washed once in Denley CellWash with 200 μl. followed by an aspiration step to 100 μl final volume. For a non-cell based assay, each well contains a fluorescent molecule, such as fluo-3. The supernatant is added to the well, and a change in fluorescence is detected.

To measure the fluorescence of intracellular calcium, the FL PR is set for the following parameters: (1) System gain is 300-800 mW; (2) Exposure time is 0.4 second; (3) Camera F/stop is F/2; (4) Excitation is 488 nm; (5) Emission is 530 nm; and (6) Sample addition is 50 ul. Increased emission at 5.30 nm indicates an extracellular signaling event caused by the a molecule, either LNFR-HKAEF92 or a molecule induced by LNFR-HKAEF92, which has resulted in an increase in the intracellular Ca²⁺ concentration. Example 19: High-Throughput Screening Assay Identifying Tyrosine Kinase Activity

The Protein Tyrosine Kinases (PTK) represent a diverse group of transmembrane and cytoplasmic kinases. Within the Receptor Protein Tyrosine Kinase RPTK) group are receptors for a range of mitogenic and metabolic growth factors including the PDGF. FGF, EGF, NGF, HGF and Insulin receptor subfamilies. In addition there are a large family of RPTKs for which the corresponding ligand is unknown. Ligands for RPTKs include mainly secreted small proteins, but also membrane -bound and extracellular matrix proteins. Activation of RPTK by ligands involves ligand-mediated receptor dimerization, resulting in transphosphorylation of the receptor subunits and activation of the cytoplasmic tyrosine kinases. The cytoplasmic tyrosine kinases include receptor associated tyrosine kinases of the src -family (e.g., src, yes, lck, lyn,fyn) and non-receptor linked and cytosolic protein tyrosine kinases, such as the Jak family, members of which mediate signal transduction triggered by the cytokine superfamily of receptors (e.g., the Interleukins, Interferons, GM-CSF, and Leptin).

Because of the wide range of known factors capable of stimulating tyrosine kinase activity, identifying whether INFR-HKAEF92 or a molecule induced by LNFR-HKAEF92 is capable of activating tyrosine kinase signal transduction pathways is of interest. Therefore, the following protocol is designed to identify such molecules capable of activating the tyrosine kinase signal transduction pathways.

Seed target cells (e.g., primary keratinocytes) at a density of approximately 25,000 cells per well in a 96 well Loprodyne Silent Screen Plates purchased from Nalge Nunc (Naperville, LL). The plates are sterilized with two 30 minute rinses with 100% ethanol, rinsed with water and dried overnight. Some plates are coated for 2 hr with 100 ml of cell culture grade type I collagen (50 mg/ml), gelatin (2%) or polylysine (50 mg/ml), all of which can be purchased from Sigma Chemicals (St. Louis, MO) or 10% Matrigel purchased from Becton Dickinson (Bedford,MA), or calf serum, rinsed with PBS and stored at 4°C. Cell growth on these plates is assayed by seeding 5,000 cells/well in growth medium and indirect quantitation of cell number through use of alamar Blue as described by the manufacturer Alamar Biosciences, Inc. (Sacramento, CA) after 48 hr. Falcon plate covers #3071 from Becton Dickinson (Bedford,MA) are used to cover the Loprodyne Silent Screen Plates. Falcon Microtest ILL cell culture plates can also be used in some proliferation experiments.

To prepare extracts. A431 cells are seeded onto the nylon membranes of Loprodyne plates (20,000/200mi/well) and cultured overnight in complete medium. Cells are quiesced by incubation in serum-free basal medium for 24 hr. After 5-20 minutes, treatment with EGF (60ng/ml) or 50 μl of the supernatant produced in Example 11, the medium was removed and 100 ml of extraction buffer ((20 mM HEPES pH 7.5, 0.15 M NaCl, 1% Triton X-100, 0.1% SDS, 2 mM Na3VO4, 2 mM Na4P207 and a cocktail of protease inhibitors (# 1836170) obtained from Boeheringer Mannheim (Indianapolis, LN) is added to each well and the plate is shaken on a rotating shaker for 5 minutes at 4°C. The plate is then placed in a vacuum transfer manifold and the extract filtered through the 0.45 mm membrane bottoms of each well using house vacuum. Extracts are collected in a 96-well catch/assay plate in the bottom of the vacuum manifold and immediately placed on ice. To obtain extracts clarified by centrifugation, the content of each well, after detergent solubilization for 5 minutes, is removed and centrifuged for 15 minutes at 4°C at 16,000 x g.

Test the filtered extracts for levels of tyrosine kinase activity. Although many methods of detecting tyrosine kinase activity are known, one method is described here.

Generally, the tyrosine kinase activity of a supernatant is evaluated by determining its ability to phosphorylate a tyrosine residue on a specific substrate (a biotinylated peptide). Biotinylated peptides that can be used for this purpose include PSK1 (corresponding to amino acids 6-20 of the cell division kinase cdc2-p34) and PSK2 (corresponding to amino acids 1-17 of gastrin). Both peptides are substrates for a range of tyrosine kinases and are available from Boehringer Mannheim.

The tyrosine kinase reaction is set up by adding the following components in order. First, add 10 μl of 5 μM Biotinylated Peptide, then 10 μl ATPMg²⁺ (5 mM ATP/50 mM MgCIN then 10 μl of 5x Assay Buffer (40 mM imidazole hydrochloride, pH 7.3, 40 mM b-glycerophosphate, 1 mM EGTA, 100 mM MgCl₂, 5 mM MnCl₂, 0.5 mg/ml BSA), then 5 μl of Sodium Vanadate (1 mM), and then 5 μl of water. Mix the components gently and preincubate the reaction mix at 30°C for 2 min. Initial the reaction by adding 10 μl of the control enzyme or the filtered supernatant. The tyrosine kinase assay reaction is then terminated by adding 10 μl of 120 mm EDTA and place the reactions on ice.

Tyrosine kinase activity is determined by transferring 50 μl aliquot of reaction mixture to a microtiter plate (MTP) module and incubating at 37°C for 20 min. This allows the streptavadin coated 96 well plate to associate with the biotinylated peptide. Wash the MTP module with 300 μl well of PBS four times. Next add 75 μl of anti-phospotyrosine antibody conjugated to horse radish peroxidase(anti-P-Tyr-POD (0.5 μl/ml)) to each well and incubate at 37°C for one hour. Wash the well as above. Next add 100 μl of peroxidase substrate solution (Boehringer Mannheim) and incubate at room temperature for at least 5 min (up to 30 min). Measure the absorbance of the sample at 405 nm by using ELIS A reader. The level of bound peroxidase activity is quantitated using an ELISA reader and reflects the level of tyrosine kinase activity.

Example 20: High-Throughput Screening Assay Identifying Phosphorylation Activity

As a potential alternative and/or compliment to the assay of protein tyrosine kinase activity described in Example 19, an assay which detects activation (phosphorylation) of major intracellular signal transduction intermediates can also be used. For example, as described below one particular assay can detect tyrosine phosphorylation of the Erk-1 and Erk-2 kinases. However, phosphorylation of other molecules, such as Raf. INK, p38 MAP, Map kinase kinase (MEK), MEK kinase, Src, Muscle specific kinase (MuSK), IRAK, Tec, and Janus, as well as any other phosphoserine, phospho tyrosine, or phosphothreonine molecule, can be detected by substituting these molecules for Erk-1 or Erk-2 in the following assay.

Specifically, assay plates are made by coating the wells of a 96-well ELISA plate with 0.1 ml of protein G (1 μg/ml) for 2 hr at room temp (RT). The 5 plates are then rinsed with PBS and blocked with 3% BSA7PBS for 1 hr at RT. The protein G plates are then treated with 2 commercial monoclonal antibodies (100 ng/well) against Erk-1 and Erk-2 (1 hr at RT; available from Santa Cruz Biotechnology). To detect other molecules, this step can easily be modified by substituting a monoclonal antibody detecting any of the above described molecules. After 3-5 rinses with PBS, the plates are stored at 4°C until use. A431 cells are seeded at 20,000/well in a 96-well Loprodyne filterplate and cultured overnight in growth medium. The cells are then starved for 48 hr in basal medium (DMEM) and then treated with EGF (6 ng/well) or 50 μl of the supematants obtained in Example 11 for 5-20 minutes. The cells are then solubilized and extracts filtered directly into the assay plate.

After incubation with the extract for lhr at RT, the wells are again rinsed. As a positive control, a commercial preparation of MAP kinase (10 ng/well) is used in place of A431 extract. Plates are then treated with a commercial polyclonal (rabbit) antibody (1 μg/ml) which specifically recognizes the phosphorylated epitope of the Erk- 1 and Erk-2 kinases (1 hr at RT). This antibody is biotinylated by standard procedures. The bound polyclonal antibody is then quantitated by successive incubations with Europium-streptavidin and Europium fluorescence enhancing reagent in the Wallac DELFIA instrument (time-resolved fluorescence). An increased fluorescent signal over background indicates a phosphorylation by LNFR-HKNEF92 or a molecule induced by LΝFR-HKAEF92.

Example 21: Method of Determining Alterations in the INFR-HKAEF92 Gene

RNA isolated from entire families or individual patients presenting with a phenotype of interest (such as a disease) is be isolated. cDNA is then generated from these RNA samples using protocols known in the art (see. Sambrook, et al, supra)

The cDNA is then used as a template for PCR. employing primers surrounding regions of interest in SEQ ID NO: 1. Suggested PCR conditions consist of 35 cycles at 95°C for 30 seconds; 60-120 seconds at 52-58°C: and 60-120 seconds at 70°C, using buffer solutions described by Sidransky and colleagues (Science

252:706 (1991)).

PCR products are then sequenced using primers labeled at the 5' end with T4 polynucleotide kinase. employing SequiTherm Polymerase (Epicentre Technologies).

The intron-exon borders of selected exons of LNFR-HKAEF92 are also determined and genomic PCR products analyzed to confirm the results. PCR products harboring suspected mutations in NFR-HKAEF92 are then cloned and sequenced to validate the results of the direct sequencing.

PCR products of LNFR-HKAEF92 are cloned into T-tailed vectors as described by Holton and Graham (Nucl. Acids Res. 19:1156 (1991)) and sequenced with T7 polymerase (United States Biochemical). Affected individuals are identified by mutations in LNFR-HKAEF92 not present in unaffected individuals.

Genomic rearrangements are also observed as a method of determining alterations in the LNFR-HKAEF92 gene. Genomic clones isolated according to Example 2 are nick-translated with digoxigenindeoxy-uridine 5'-triphosphate (Boehringer Manheim), and FISH performed as described by Johnson and coworkers (Methods Cell Biol. 35:73-99 (1991)). Hybridization with the labeled probe is carried out using a vast excess of human cot- 1 DNA for specific hybridization to the INFR-HKAEF92 genomic locus. Chromosomes are counterstained with 4,6-diamino-2-phenylidole and propidium iodide, producing a combination of C- and R-bands. Aligned images for precise mapping are obtained using a triple-band filter set (Chroma Technology, Brattleboro, VT) in combination with a cooled charge -coupled device camera (Photometries, Tucson, AZ) and variable excitation wavelength filters (Johnson, C. et al, Genet. Anal. Tech. Appl. 8:75 (1991)). Image collection, analysis and chromosomal fractional length measurements are performed using the ISee Graphical Program System. (Inovision Corporation. Durham, NC). Chromosome alterations of the genomic region of LNFR-HKAEF92 (hybridized by the probe) are identified as insertions, deletions, and translocations. These LNFR-HKAEF92 alterations are used as a diagnostic marker for an associated disease.

Example 22: Method of Detecting Abnormal Levels of INFR-HKAEF92 in a Biological Sample

LNFR-HKAEF92 polypeptides can be detected in a biological sample, and if an increased or decreased level of LNFR-HKAEF92 is detected, this polypeptide is a marker for a particular phenotype. Methods of detection are numerous, and thus, it is understood that one skilled in the art can modify the following assay to fit their particular needs.

For example, antibody-sandwich ELISAs are used to detect LNFR-HKAEF92 in a sample, preferably a biological sample. Wells of a microtiter plate are coated with specific antibodies to INFR-HKAEF92, at a final concentration of 0.2 to 10 μg/ml.

The antibodies are either monoclonal or polyclonal and are produced by the method described in Example 10. The wells are blocked so that non-specific binding of

INFR-HKAEF92 to the well is reduced. The coated wells are then incubated for > 2 hours at RT with a sample containing LNFR-HKAEF92. Preferably, serial dilutions of the sample should be used to validate results. The plates are then washed three times with deionized or distilled water to remove unbounded LNFR-HKAEF92. Next, 50 μl of specific antibody-alkaline phosphatase conjugate, at a concentration of 25-400 ng, is added and incubated for 2 hours at room temperature. The plates are again washed three times with deionized or distilled water to remove unbounded conjugate.

Add 75 μl of 4-methylumbelliferyl phosphate (MUP) or p-nitrophenyl phosphate (NPP) substrate solution to each well and incubate 1 hour at room temperature. Measure the reaction by a microtiter plate reader. Prepare a standard curve, using serial dilutions of a control sample, and plot LNFR-HKAEF92 polypeptide concentration on the X-axis (log scale) and fluorescence or absorbance of the Y-axis (linear scale). Interpolate the concentration of the LNFR-HKAEF92 in the sample using the standard curve.

Example 23: Formulating a Polypeptide

The INFR-HKAEF92 composition will be formulated and dosed in a fashion consistent with good medical practice, taking into account the clinical condition of the individual patient (especially the side effects of treatment with the

LNFR-HKAEF92 polypeptide alone), the site of delivery, the method of administration, the scheduling of administration, and other factors known to practitioners. The "effective amount" for purposes herein is thus determined by such considerations. As a general proposition, the total pharmaceutically effective amount of

INFR-HKAEF92 administered parenterally per dose will be in the range of about 1 μg kg/day to 10 mg kg/day of patient body weight, although, as noted above, this will be subject to therapeutic discretion. More preferably, this dose is at least 0.01 mg/kg/day, and most preferably for humans between about 0.01 and 1 mg/kg/day for the hormone. If given continuously, LNFR-HKAEF92 is typically administered at a dose rate of about 1 μg/kg/hour to about 50 μg/kg/hour, either by 1-4 injections per day or by continuous subcutaneous infusions, for example, using a mini-pump. An intravenous bag solution may also be employed. The length of treatment needed to observe changes and the interval following treatment for responses to occur appears to vary depending on the desired effect.

Pharmaceutical compositions containing LNFR-HKAEF92 are administered orally, rectally, parenterally, intracistemally, intravaginally. intraperitoneally, topically (as by powders, ointments, gels, drops or transdermal patch), bucally, or as an oral or nasal spray. "Pharmaceutically acceptable carrier" refers to a non-toxic solid, semisolid or liquid filler, diluent, encapsulating material or formulation auxiliary of any type. The term "parenteral" as used herein refers to modes of administration which include intravenous, intramuscular, intraperitoneal, intrastemal, subcutaneous and intraarticular injection and infusion.

LNFR-HKAEF92 is also suitably administered by sustained-release systems. Suitable examples of sustained-release compositions include semi-permeable polymer matrices in the form of shaped articles, e.g., films, or mirocapsules. Sustained-release matrices include polylactides (U.S. Pat. No. 3,773,919, EP 58,481), copolymers of L-glutamic acid and gamma-ethyl-L-glutamate (Sidman, U., et al, Biopolymers 22:547-556 (1983)), poly (2- hydroxyethyl methacrylate) (Langer, R., et al, J Biomed. Mater. Res. 15: 167-277 (1981); Langer, R. Chem. Tech. 12:98-105 (1982)), ethylene vinyl acetate (Langer, R., et al.) or poly-D- (-)-3-hydroxybutyric acid (EP 133,988). Sustained-release compositions also include liposomally entrapped LNFR- HKAEF92 polypeptides. Liposomes containing the LNFR-HKAEF92 are prepared by methods known per se (DE 3.218.121 ; Epstein, et al, Proc. Natl. Acad Sci. USA 82:3688-3692 (1985); Hwang, et al, Proc. Natl Acad Sci. USA 77:4030-4034 ( 1980): EP 52,322; EP 36,676; EP 88,046; EP 143,949; EP 142,641 ; Japanese Pat. Appl. 83-1 18008; U.S. Pat. Nos. 4.485,045 and 4,544,545; and EP 102,324). Ordinarily, the liposomes are of the small (about 200-800 Angstroms) unilamellar type in which the lipid content is greater than about 30 mol. percent cholesterol, the selected proportion being adjusted for the optimal secreted polypeptide therapy. For parenteral administration, in one embodiment, INFR-HKAEF92 is formulated generally by mixing it at the desired degree of purity, in a unit dosage injectable form (solution, suspension, or emulsion), with a pharmaceutically acceptable carrier, i.e.. one that is non-toxic to recipients at the dosages and concentrations employed and is compatible with other ingredients of the formulation. For example, the formulation preferably does not include oxidizing agents and other compounds that are known to be deleterious to polypeptides.

Generally, the formulations are prepared by contacting INFR-HKAEF92 uniformly and intimately with liquid carriers or finely divided solid carriers or both. Then, if necessary, the product is shaped into the desired formulation. Preferably the carrier is a parenteral carrier, more preferably a solution that is isotonic with the blood of the recipient. Examples of such carrier vehicles include water, saline, Ringer's solution, and dextrose solution. Non-aqueous vehicles such as fixed oils and ethyl oleate are also useful herein, as well as liposomes. The earner suitably contains minor amounts of additives such as substances that enhance isotonicity and chemicai stability. Such materials are non-toxic to recipients at the dosages and concentrations employed, and include buffers such as phosphate, citrate, succinate, acetic acid, and other organic acids or their salts; antioxidants such as ascorbic acid; low molecular weight (less than about ten residues) polypeptides, e.g., polyarginine or tripeptides; proteins, such as semm albumin, gelatin, or immunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone; amino acids, such as glycine, glutamic acid, aspartic acid, or arginine; monosaccharides, disaccharides, and other carbohydrates including cellulose or its derivatives, glucose, manose, or dextrins; chelating agents such as EDTA; sugar alcohols such as mannitol or sorbitol; counterions such as sodium; and or nonionic surfactants such as polysorbates, poloxamers, or PEG.

LNFR-HKAEF92 is typically formulated in such vehicles at a concentration of about 0.1 mg/ml to 100 mg/ml, preferably 1-10 mg/ml, at a pH of about 3 to 8. It will be understood that the use of certain of the foregoing excipients, carriers, or stabilizers will result in the formation of polypeptide salts.

LNFR-HKAEF92 used for therapeutic administration can be sterile. Sterility is readily accomplished by filtration through sterile filtration membranes (e.g., 0.2 micron membranes). Therapeutic polypeptide compositions generally are placed into a container having a sterile access port, for example, an intravenous solution bag or vial having a stopper pierceable by a hypodermic injection needle.

INFR-HKAEF92 polypeptides ordinarily will be stored in unit or multi-dose containers, for example, sealed ampoules or vials, as an aqueous solution or as a lyophilized formulation for reconstitution. As an example of a lyophilized formulation, 10-ml vials are filled with 5 ml of sterile-filtered 1% (w/v) aqueous LNFR-HKAEF92 polypeptide solution, and the resulting mixture is lyophilized. The infusion solution is prepared by reconstituting the lyophilized INFR-HKAEF92 polypeptide using bacteriostatic Water-For-Injection (WFI).

The invention also provides a pharmaceutical pack or kit comprising one or more containers filled with one or more of the ingredients of the pharmaceutical compositions of the invention. Associated with such container(s) can be a notice in the form prescribed by a governmental agency regulating the manufacture, use or sale of pharmaceuticals or biological products, which notice reflects approval by the agency of manufacture, use or sale for human administration. In addition, INFR-HKAEF92 may be employed in conjunction with other therapeutic compounds.

Example 24: Method of Treating Decreased Levels of INFR-HKAEF92

The present invention relates to a method for treating an individual in need of a decreased level of LNFR-HKAEF92 activity in the body comprising, administering to such an individual a composition comprising a therapeutic ally effective amount of LNFR-HKAEF92 antagonist. Preferced antagonists for use in the present invention are LNFR-HKAEF92 -specific antibodies.

Moreover, it will be appreciated that conditions caused by a decrease in the standard or normal expression level of LNFR-HKAEF92 in an individual can be treated by administering LNFR-HKAEF92, preferably in the secreted form. Thus, the invention also provides a method of treatment of an individual in need of an increased level of INFR-HKAEF92 polypeptide comprising administering to such an individual a pharmaceutical composition comprising an amount of LNFR-HKAEF92 to increase the activity level of LNFR-HKAEF92 in such an individual.

For example, a patient with decreased levels of LNFR-HKAEF92 polypeptide receives a daily dose 0.1-100 μg/kg of the polypeptide for six consecutive days. Preferably, the polypeptide is in the secreted form. The exact details of the dosing scheme, based on administration and formulation, are provided in Example 23.

Example 25: Method of Treating Increased Levels of INFR-HKAEF92

The present invention also relates to a method for treating an individual in need of an increased level of INFR-HKAEF92 activity in the body comprising administering to such an individual a composition comprising a therapeutically effective amount of LNFR-HKAEF92 or an agonist thereof.

Antisense technology is used to inhibit production of INFR-HKAEF92. This technology is one example of a method of decreasing levels of LNFR-HKAEF92 polypeptide, preferably a secreted form, due to a variety of etiologies, such as cancer.

For example, a patient diagnosed with abnormally increased levels of INFR-HKAEF92 is administered intravenously antisense polynucleotides at 0.5, 1.0, 1.5, 2.0 and 3.0 mg/kg day for 21 days. This treatment is repeated after a 7-day rest period if the treatment was well tolerated. The formulation of the antisense polynucleotide is provided in Example 23.

Example 26: Method of Treatment Using Gene Therapy

One method of gene therapy transplants fibroblasts, which are capable of expressing LNFR-HKAEF92 polypeptides, onto a patient. Generally, fibroblasts are obtained from a subject by skin biopsy. The resulting tissue is placed in tissue-culture medium and separated into small pieces. Small chunks of the tissue are placed on a wet surface of a tissue culture flask, approximately ten pieces are placed in each flask. The flask is turned upside down, closed tight and left at room temperature over night. After 24 hours at room temperature, the flask is inverted and the chunks of tissue remain fixed to the bottom of the flask and fresh media (e.g., Ham's F 12 media, with 10% FBS, penicillin and streptomycin) is added. The flasks are then incubated at 37°C for approximately one week.

At this time, fresh media is added and subsequently changed every several days. After an additional two weeks in culture, a monolayer of fibroblasts emerge. The monolayer is trypsinized and scaled into larger flasks. pMV-7 (Kirschmeier, P.T., et al, DNA 7:219-25 (1988)), flanked by the long terminal repeats of the Moloney murine sarcoma vims, is digested with Eco RI and Hin dill and subsequently treated with calf intestinal phosphatase. The linear vector is fractionated on agarose gel and purified, using glass beads. The cDNA encoding INFR-HKAEF92 can be amplified using PCR primers which correspond to the 5' and 3' end sequences respectively as set forth in Example 1. Preferably, the 5' primer contains an Eco RI site and the 3' primer includes a Hin din site. Equal quantities of the Moloney murine sarcoma vims linear backbone and the amplified Eco RI and Hin dill fragment are added together, in the presence of T4 DNA ligase. The resulting mixture is maintained under conditions appropriate for ligation of the two fragments. The ligation mixture is then used to transform bacteria HB 101, which are then plated onto agar containing kanamycin for the purpose of confirming that the vector contains properly inserted LNFR-HKAEF92. The amphotropic pA317 or GP+aml2 packaging cells are grown in tissue culture to confluent density in Dulbecco's Modified Eagles Medium (DMEM) with 10% calf semm (CS), penicillin and streptomycin. The MSV vector containing the LNFR-HKAEF92 gene is then added to the media and the packaging cells transduced with the vector. The packaging cells now produce infectious viral particles containing the LNFR-HKAEF92 gene (the packaging cells are now refened to as producer cells).

Fresh media is added to the transduced producer cells, and subsequently, the media is harvested from a 10 cm plate of confluent producer cells. The spent media, containing the infectious viral particles, is filtered through a millipore filter to remove detached producer cells and this media is then used to infect fibroblast cells. Media is removed from a sub-confluent plate of fibroblasts and quickly replaced with the media from the producer cells. This media is removed and replaced with fresh media. If the titer of virus is high, then virtually all fibroblasts will be infected and no selection is required. If the titer is very low. then it is necessary to use a retroviral vector that has a selectable marker, such as neo or his. Once the fibroblasts have been efficiently infected, the fibroblasts are analyzed to determine whether INFR-HKAEF92 protein is produced.

The engineered fibroblasts are then transplanted onto the host, either alone or after having been grown to confluence on cytodex 3 microcarrier beads. It will be clear that the invention may be practiced otherwise than as particularly described in the foregoing description and examples. Numerous modifications and variations of the present invention are possible in light of the above teachings and, therefore, are within the scope of the appended claims.

The entire disclosure of each document cited (including patents, patent applications, journal articles, abstracts, laboratory manuals, books, or other disclosures) in the Background of the Invention, Detailed Description, and Examples is hereby incoφorated herein by reference. INDICATIONS RELATING TO A DEPOSITED MICROORGANISM

( PCT Rule \ 3bis)

A. The indications made below relate to the microorganism referred to in the descπption on page . line 31

B. IDENTrnCAΗONOFDEPOSIT Fuπher deposits are identified on an additional sheet | |

Name of depositary institution American Type Culture Collection

Address of depositary institution (including postal code and country)

10801 University Boulevard Manassas, Virginia 20110-2209 United States of America

Date of deposit Accession Number

April 7, 1998 209746

C. ADDITIONAL INDICATIONS iteαve blank if not applicable) This information is continued on an additional sheet | |

D. DESIGNATED STATES FOR WHICH INDICATIONS ARE MXOEln i".e dicationsarenotforalldesignatedStates)

Europe in respect to those designations in which a European Patent is sought a sample of the deposited microorganism will be made available until the publication of the mention of the grant of the European patent or until the date on which application has been refused or withdrawn or is deemed to be withdrawn, only by the issue of such a sample to an expert nominated by the person requesting the sample (Rule 28 (4) EPC).

E. SEPARATE FURNISHING OF INDICATIONS t leave blank ifnoi applicable ,

The indications listed below will be submitted to the International Bureau later tspecn me general nature of the indications e g "Accession Number of Deposit")

For receiving Office use only For intemational Bureau use onlv

I j This sheet was received with the international application D This sheet w as received bv the International Bureau on-

Authoπzed officer Authoπzed officer ATCC Deposit No. 209746

CANADA

The applicant requests that, until either a Canadian patent has been issued on the basis of an application or the application has been refused, or is abandoned and no longer subject to reinstatement, or is withdrawn, the Commissioner of Patents only authonzes the furnishing of a sample of the deposited biological matenal refened to in the application to an independent expert nominated by the Commissioner, the applicant must, by a wntten statement, inform the International Bureau accordingly before completion of technical preparations for pubhcation of the international application

NORWAY

The applicant hereby requests that the application has been laid open to public inspection (by the Norwegian Patent Office), or has been finally decided upon by the Norwegian Patent Office without having been laid open inspection, the furnishing of a sample shall only be effected to an expert in the art The request to this effect shall be filed by the applicant with the Norwegian Patent Office not later than at the time when the application is made available to the public under Sections 22 and 33(3) of the Norwegian Patents Act If such a request has been filed by the applicant, any request made by a third party for the furnishing of a sample shall indicate the expert to be used That expert may be any person entered on the list of recognized experts drawn up by the Norwegian Patent Office or any person approved by the applicant in the individual case

AUSTRALIA

The applicant hereby gives notice that the furnishing of a sample of a microorganism shall only be effected pnor to the grant of a patent, or pnor to the lapsing, refusal or withdrawal of the application, to a person who is a skilled addressee without an interest in the invention (Regulation 3.25(3) of the Australian Patents Regulations)

FINLAND

The applicant hereby requests that, until the application has been laid open to public inspection (by the National Board of Patents and Regulations), or has been finally decided upon by the National Board of Patents and Registration without having been laid open to public inspection, the furnishing of a sample shall only be effected to an expert in the art

UNITED KINGDOM

The applicant hereby requests that the furnishing of a sample of a microorganism shall only be made available to an expert The request to this effect must be filed by the applicant with the International Bureau before the completion of the technical preparations for the international publication of the application ATCC Deposit No. 209746

DENMARK

The applicant hereby requests that, until the application has been laid open to public inspection (by the Danish Patent Office), or has been finally decided upon by the Danish Patent office without having been laid open to public inspection, the furnishing of a sample shall only be effected to an expert in the art. The request to this effect shall be filed by the applicant with the Danish Patent Office not later that at the time when the application is made available to the public under Sections 22 and 33(3) of the Danish Patents Act. If such a request has been filed by the applicant, any request made by a third party for the furnishing of a sample shall indicate the expert to be used. That expert may be any person entered on a list of recognized experts drawn up by the Danish Patent Office or any person by the applicant in the individual case.

SWEDEN

The applicant hereby requests that, until the application has been laid open to public inspection (by the Swedish Patent Office), or has been finally decided upon by the Swedish Patent Office without having been laid open to public inspection, the furnishing of a sample shall only be effected to an expert in the art. The request to this effect shall be filed by the applicant with the International Bureau before the expiration of 16 months from the priority date (preferably on the Form PCT/RO/134 reproduced in annex Z of Volume I of the PCT Applicant's Guide). If such a request has been filed by the applicant any request made by a third party for the furnishing of a sample shall indicate the expert to be used. That expert may be any person entered on a list of recognized experts drawn up by the Swedish Patent Office or any person approved by a applicant in the individual case.

NETHERLANDS

The applicant hereby requests that until the date of a grant of a Netherlands patent or until the date on which the application is refused or withdrawn or lapsed, the microorganism shall be made available as provided in the 31 F(l ) of the Patent Rules only by the issue of a sample to an expert. The request to this effect must be furnished by the applicant with the Netherlands Industrial Property Office before the date on which the application is made available to the public under Section 22C or Section 25 of the Patents Act of the Kingdom of the Netherlands, whichever of the two dates occurs earlier.

Claims

What is Claimed Is:

1. An isolated nucleic acid molecule comprising a polynucleotide having a nucleotide sequence at least 95% identical to a sequence selected from the group consisting of. (a) a nucleotide sequence encoding residues 1 to 311 of SEQ ID NO:2;

(b) a nucleotide sequence encoding residues 2 to 311 of SEQ ID NO:2;

(c) a nucleotide sequence encoding residues 30 to 311 of SEQ ID NO:2;

(d) a nucleotide sequence encoding residues 30 to 233 in SEQ ID NO:2;

(e) a nucleotide sequence encoding a polypeptide having the complete amino acid sequence encoded by the cDNA clone HKAEF92 contained in ATCC Deposit

No. 209746;

(f) a nucleotide sequence encoding the polypeptide having the complete amino acid sequence excepting the N-terminal methionine encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746; (g) a nucleotide sequence encoding the mature polypeptide having the amino acid sequence encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746;

(h) a nucleotide sequence encoding the extracellular domain of the polypeptide encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746; and

(i) a nucleotide sequence complementary to any of the nucleotide sequences in (a), (b), (c), (d), (e), (f), (g) or (h) above.

2. The nucleic acid molecule of claim 1 wherein said polynucleotide has the complete nucleotide sequence in Figure 1 (SEQ ID NO:l).

3. The nucleic acid molecule of claim 1 wherein said polynucleotide has the nucleotide sequence in Figure 1 (SEQ ID NO: l) encoding the LNFR-HKAEF92 polypeptide having the amino acid sequence in positions 1 to 311 of SEQ ID NO:2.

4. The nucleic acid molecule of claim 1 wherein said polynucleotide has the nucleotide sequence in Figure 1 (SEQ ID NO: 1) encoding residues 30 to 233 in SEQ ID NO:2.

5. An isolated nucleic acid molecule comprising a polynucleotide having a nucleotide sequence at least 95% identical to a sequence selected from the group consisting of: (a) a nucleotide sequence encoding a polypeptide comprising the amino acid sequence of residues n-233 of SEQ ID NO:2, where n is an integer in the range of 19-89;

(b) a nucleotide sequence encoding a polypeptide comprising the amino acid sequence of residues 1-m of SEQ ID NO:2, where m is an integer in the range of 222-233;

(c) a nucleotide sequence encoding a polypeptide having the amino acid sequence consisting of residues n-m of SEQ ID NO:2, where n and m are integers as defined respectively in (a) and (b) above; and

(d) a nucleotide sequence encoding a polypeptide consisting of a portion of the complete LNFR-HKAEF92 amino acid sequence encoded by the cDNA clone

HKAEF92 contained in ATCC Deposit No. 209746 wherein said portion excludes from 1 to about 88 amino acid residues from the amino terminus of said complete amino acid sequence;

(e) a nucleotide sequence encoding a polypeptide consisting of a portion of the complete LNFR-HKAEF92 amino acid sequence encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No.209746 wherein said portion excludes from about 78 to 89 amino acids from the carboxy terminus of said complete amino acid sequence; and

(f) a nucleotide sequence encoding a polypeptide consisting of a portion of the complete LNFR-HKAEF92 amino acid sequence encoded by the cDNA clone contained in ATCC Deposit No. 209746 wherein said portion include a combination of any of the amino terminal and carboxy terminal deletions in (d) and (e), above.

6. The nucleic acid molecule of claim 1 wherein said polynucleotide has the complete nucleotide sequence of the cDNA clone HKAEF92 contained in ATCC

Deposit No. 209746.

7. The nucleic acid molecule of claim 1 wherein said polynucleotide has the nucleotide sequence encoding the INFR-HKAEF92 polypeptide having the complete amino acid sequence excepting the N-terminal methionine encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746.

8. The nucleic acid molecule of claim 1 wherein said polynucleotide has the nucleotide sequence encoding the extracellular domain of the LNFR-HKAEF92 polypeptide having the amino acid sequence encoded by the cDNA clone HKAEF92 contained in ATCC Deposit No. 209746.

9. An isolated nucleic acid molecule comprising a polynucleotide which hybridizes under stringent hybridization conditions to a polynucleotide having a nucleotide sequence identical to a nucleotide sequence in (a), (b), (c), (d), (e), (f), (g), (h) or (i) of claim 1 wherein said polynucleotide which hybridizes does not hybridize under stringent hybridization conditions to a polynucleotide having a nucleotide sequence consisting of only A residues or of only T residues.

10. An isolated nucleic acid molecule comprising a polynucleotide which encodes the amino acid sequence of an epitope-bearing portion of a LNFR-HKAEF92 polypeptide having an amino acid sequence in (a), (b), (c), (d), (e), (f), (g) or (h) of claim 1.

11. The isolated nucleic acid molecule of claim 10, which encodes an epitope-bearing portion of a LNFR-HKAEF92 polypeptide wherein the amino acid sequence of said portion is selected from the group of sequences in SEQ ID NO:2 consisting of: from about about residue 69 to about residue 77, from about residue 92 to about residue 107, from about residue 129 to about residue 162, from about residue 172 to about 199, and from about 272 to about 307.

12. A method for making a recombinant vector comprising inserting an isolated nucleic acid molecule of claim 1 into a vector.

13. A recombinant vector produced by the method of claim 12.

14. A method of making a recombinant host cell comprising introducing the recombinant vector of claim 13 into a host cell.

15. A recombinant host cell produced by the method of claim 14.

16. A recombinant method for producing a LNFR-HKAEF92 polypeptide, comprising culturing the recombinant host cell of claim 15 under conditions such that said polypeptide is expressed and recovering said polypeptide.

17. An isolated LNFR-HKAEF92 polypeptide comprising an amino acid sequence at least 95% identical to a sequence selected from the group consisting of: (a) the amino acid sequence shown as 1 to 311 of SEQ ID NO:2;

(b) the amino acid sequence shown as 2 to 311 of SEQ LD NO:2;

(c) the amino acid sequence shown as 30 to 311 of SEQ ID NO:2;

(d) the amino acid sequence shown as 30 to 233 of SEQ ID NO:2;

(e) the full length polypeptide encoded by the human cDNA clone HKAEF92;

(f) the full length polypeptide except the N-terminal methoinine encoded by the human cDNA clone HKAEF92;

(g) the mature polypeptide encoded by cDNA clone HKAEF92; and (h) the extracellular domain of the polypeptide encoded by cDN A clone HKAEF92.

18. An isolated polypeptide comprising an epitope-bearing portion of the INFR-HKAEF92 protein, wherein said portion is selected from the group consisting of: a polypeptide comprising amino acid residues from about about residue 69 to about residue 77, from about residue 92 to about residue 107, from about residue 129 to about residue 162, from about residue 172 to about 199, and from about 272 to about 307, all of SEQ ID NO:2.

19. An isolated antibody that binds specifically to a LNFR-HKAEF92 polypeptide of claim 17.