NZ623656B2 - Anti-??tcr antibody - Google Patents

Abstract

Disclosed is a humanised monoclonal antibody specific for the human ??TCR/CD3 complex which comprises a heavy chain variable region comprising an amino acid sequence selected from the group consisting of the sequences set forth as SEQ ID NOs: 7, 12, 13, 15 and 16, and a light chain variable region comprising the amino acid sequence set forth as SEQ ID NO: 14, wherein the sequences are as disclosed in the complete specification. Also disclosed is the use of said antibody in in the manufacture of a medicament for use in suppressing a T cell mediated response in a subject. omprising the amino acid sequence set forth as SEQ ID NO: 14, wherein the sequences are as disclosed in the complete specification. Also disclosed is the use of said antibody in in the manufacture of a medicament for use in suppressing a T cell mediated response in a subject.

Description

Anti-ocBTCR antibody The present invention relates to an dy specific for the alpha beta T cell or (dBTCR). I n particular, the invention relates to a humanized anti-ocBTCR antibody, which is derived from the murine monoclonal antibody BMAOSt, and the use of said humanized LA dy in immunosuppressive therapy.

Introduction The use of immunosuppressive agents in autoimmune diseases and organ transplant therapy is well documented; however the process is far from optimal. Toxicity, opportunistic ions, cytokine storm and increased risk of cancer are prevalent in patients d with these agents. The use of ics in this arena has improved t outcome to some degree yet these side effects remain evident. pose The use of polyclonal antisera against lymphocytes is well known for the pur of immunosuppression. However, antisera are labor—intensive to produce, show properties which vary between batches, and the specificity which can be obtained using polyclonal antisera is limited. onal antibody production by hybridoma logy was first described by K6hler and Milstein (Nature 256:495—497 (1975)). As compared to polyclonal ra, monoclonal antibodies (mAbs) are more ic, and have more consistent properties. mAbs have been most frequently and successfully used for immunosuppressive therapy in clinical organ transplantation. However, most mAbs used as immunosuppressive agents for treating autoimmune diseases and in transplant patients have a broad immunosuppressive capacity, thus undesirably influencing functions of a wide um of immune cells, presumably not all involved in graft rejection.

Mouse monoclonal antibodies against T cell surface receptor antigens were first produced in 1979 using hybridoma technology (Kung et al. (1979) Science 206:347-349). Of the three monoclonal antibodies discovered by Kung et a/., one antibody ated muromonab—CD3 (OKT3) had d specificity to the CD3 receptor of the T cell, reacting with more that 95% of peripheral mature T cells without affecting immature thymocytes.

Binding of OKT3 to the CD3 complex causes internalization of the CD3 receptor and loss of CD3 positive cells from the periphery. Successful OKT3 treatment is associated with a prompt decline in CD3 positive T cells from approximately 60% to less than 5%.

OKT3 has been extensively used for the treatment of patients oing acute allograft rejection after kidney transplantation (Russell, P.S., Colvin, R.B., Cosimi, A (1984) Annu. Rev. Med. 35:63 and Cosimi, A.B., Burton, R.C., Colvin, R B ef al. (1981) Transplantation 32:535). Moreover, OKT3 and rabbit complement were used for purging U‘i mature T cells from donor marrow to t acute graft versus host disease (GVHD) in allogeneic bone marrow transplantation (Prentice, H.G., Blacklock, H.A., Janossy, G. etal. (1982) Lancet 1:700 and Blacklock, H.A., Prentice, H.G., e, MJ. etal. (1983) Exp.

Hematol. 11:37). Whereas OKT3 ent seems to be effective in the prevention of GVHD in allogeneic bone marrow transplantation for acute leukemia, a combined in / in vifro vivo treatment with OKT3 failed to prevent GVHD during therapy for severe combined immunodeficiency (Hayward, A. et al. (1982) Clin. Lab. Observ. 100:665). ponses Treatment of T cells with OKT3 s several res inconsistent with immune suppression including T cell activation, production of immune mediators and T3- modulation. The T3-antigen complex ized by CD3-mAbs (e.g., OKT3) is postulated to play a crucial role during T cell activation. beta T lymphocytes recognize peptide— MHC ligands by means of a multimeric protein ensemble termed the GB T cell antigen receptor (TCR)-CD3 complex. This structure is composed of a variable 08 TCR dimer which binds antigens and three invariant dimers (CD3ve, 55 and (C) which are involved in TCR-CD3 surface transport, ization and signal transduction. The alpha beta T cell receptor (dBTCR) is expressed on the majority (approx. 95%) of T cells and has a critical role in T cell activation via engagement of antigen displayed on MHC. The remaining 5% of cells are gamma delta T cell receptor (y8TCR) positive. The ySTCR positive cell ponse population plays an important role in the innate immune res in defense against opportunistic infections of bacterial, viral and fungal . Gamma delta T cells do not play a role in graft rejection in transplantation. Therefore, targeting the ocBTCR positive cell population and sparing the y5TCR positive population should allow for significant therapeutic efficacy whilst maintaining a baseline immune protection against opportunistic infections.

The mouse lgG2b monoclonal dy BMA031 (Borst etal. (Nov. 1990) Hum. Immunol. 29(3):175-88; EP0403156) is specific for the common determinant on the TCR alpha/beta/CD3 x, and does not bind to the gamma-delta TCR. BMA031 is highly immunosuppressive and is e of inducing apoptosis of activated T cells via a mechanism of activation—induced cell death (AICD) (Wesselborg et al. (May 1993) J. l. 150(10): 345). In vitro it inhibits a mixed lymphocyte reaction and it has shown preliminary clinical efficacy in prevention of graft rejection in a number of solid organ transplant scenarios as well as the treatment of acute graft versus host e ) (Kurrle efal. (Feb 1989) Transplant Proc. 21 (1): 1017—1019). BMA031 does not engage human Fc gamma receptors (FcyR) in the majority of the human population (approximately 10 of human possess FcyRs which do bind to mouse lgG2b isotype). As such the antibody does not cause T cell activation via cross-linking of the T cell receptor and, therefore, it does not induce T cell activation or the associated cytokine release. In this regard its profile is highly preferable over that of OKTS. However, BMA031 is a murine dy and, as such, is not suitable for repeat dosing in human subjects in view ponse of the human anti-mouse antibody (HAMA) res elicited therein.

Several humanized versions of BMA031 have been described (see, E 0403156; also Shearman eta/., (1991) J. l. 147:4366-4373). As noted in EP0403156, mere CDR ng was not sful in retaining antigen binding. One clone with significant framework modifications, EUCIV3, successfully bound to T cells; however, as noted in EP0403156, binding to the ocBTCR is not as ive as the parent BMA031 antibody as determined by flow cytometry competition assays. We have also shown that the ability of EuClV3 to inhibit an in vitro immune response is significantly reduced as compared to BMA031 (see, Fig. 2). In addition EuCIV3 was originally generated on a wild-type human IgG1 or IgG4 backbone which still retains FcyR binding. These humanized antibodies ore allowed for T cell activation, proliferation and the concomitant cytokine release and as such were significantly different to the original properties of BMA031.

The modification of antibody glycosylation is known in the art. For example, it is known that aglycosylated antibodies can have extensively modified functionality; see, Boyd et al. (1996) Mol. l. 32:1311—1318. However, aglycosylated forms of humanized BMA031, or derivatives with modified glycosylation patterns, have previously not been descnbed.

There is a need in the art, therefore, for an anti-ocBTCR humanized antibody which improves on the binding properties of EUCIV3 and advantageously retains the immunosuppressive and non-T cell-activatory properties of BMA031.

Summary of the Invention In a first aspect, there is provided a humanized monoclonal antibody which comprises the CDRs of BMA031, and retains the g ty of BMA031 for its cognate antigen. In a first embodiment, said humanized antibody comprises a heavy chain variable region sing the CDRs set forth in SEQ ID NOs: 7, 12 or 13 and the human lGH3—23 framework set forth in SEQ ID NO: 17, wherein framework position 6 is a donor residue; in an ative embodiment, framework position 18 is a donor residue. Optionally, framework positions 49 and/ 69 are donor residues.

I n a second embodiment, the humanized monoclonal antibody comprises a heavy chain U‘l variable region sing the CDRs set forth in SEQ ID NOs: 15 or 16 and the human IGHV1-3*O1 ork set forth in SEQ ID NO: 18, wherein one or more of framework positions 38, 44 and/or 48 is a donor e; in an alternative embodiment, framework ons 44 and 48 are donor residues.

I n a third embodiment, the humanized monoclonal antibody comprises a light chain variable region comprising the CDRs set forth in SEQ ID NO: 1 and the human IGKV3- 11*01 framework set forth in SEQ ID NO: 19, wherein framework positions 70 and/ 71 are donor es. Optionally, position 46 is a donor residue.

Examples of antibodies according to the first embodiment include antibodies which comprise a heavy chain variable region selected from the heavy chains comprising the sequences set forth in SEQ ID NO: 7, SEQ ID NO: 12 and SEQ ID NO: 13, and a light chain variable region sequence comprising the ce as set forth in SEQ ID NO: 1 Examples of dies ing to the second embodiment include antibodies which comprise a heavy chain variable region selected from the heavy chains comprising the sequences set forth in SEQ ID NO: 15 and SEQ ID NO: 16, and a light chain variable 2O region sing the sequence as set forth in SEQ ID NO: 14. The humanized antibodies according to the described embodiments are humanized versions of the BMA031. Their primary structures differ from that of the humanized antibody EuCIV3, which has decreased binding to the ocBTCR as ed to BMA031.

In the sequence listing, CDRs are ted by means of annotation or underlining.

Frameworks are all sequences outside of the CDRs, which are defined according to the "Kabat" numbering system and extended, where applicable, by use of “IMGT” CDR definition. If a framework residue is not indicated to be changed to match a donor sequence, it will rily be understood to be an acceptor residue.

The humanized antibodies may comprise a constant region. In one embodiment, the constant region is of human origin.

The humanized antibodies of the invention may be further modified by EC engineering.

Immunoglobulins are liable to cross—link Fcy receptors, which can lead to constitutive T cell tion for anti—T cell antibodies. In order to avoid Fcy cross—linking, dies can be modified to remove the Fc region, such as by the generation of Fab or F fragments; however, truncated immunoglobulins lack beneficial effector functions and exhibit a lower serum half—life. Therefore, the Fc region of the humanized antibody can be modified to prevent Fcy cross—linking. Exemplary techniques include generation of sylated immunoglobulins, for instance by modification of the Fc region by an N297Q mutation. Immunoglobulins which fail to bind Fcy are also described by Armour et a/., (1999) Eur. J. Immunol. -2624. The modification effected to IgG1 is known as the Aab modification, and consists in a combination of the Aa on, in which IgG residues are substituted at positions 327, 330 and 881 and , IgG2 residues substituted at positions 233-236, and the Ab mutation, in which residue 236 is deleted. In another embodiment, the glycosylation pattern of dies according to the invention can be modified.

I n one embodiment, the antibody comprised one or more of ons 8298N, T299A and Y3OOS.

I n embodiments, the dy comprises two or more of ons N297Q, S298N, T299A and YSOOS. For example, there is provided a zed antibody comprising the multiple mutations N297Q/8298N/Y3008, S298N/T299A/Y3008 or S298N/YSOOS.

I n a second aspect, there is provided a humanized monoclonal antibody which comprises the CDRs of BMA031, and retains the T cell suppression properties of BMA031.

According to one embodiment, there is ed a humanized monoclonal antibody specific for the human /CDS complex which comprises a heavy chain variable region comprising an amino acid sequence selected from the group consisting of the sequences set forth as SEQ ID NOs: 7, 12, 13, 15 and 16, and a light chain variable region comprising the amino acid sequence set forth as SEQ ID NO: 14.

In a third aspect, there is ed a nucleic acid encoding at least a heavy chain variable region of a humanized monoclonal antibody according to the preceding aspects of the described embodiments.

The nucleic acid may encode variable and constant regions of the humanized antibody. Heavy and light chains may be encoded on separate nucleic acids or on the same nucleic acid molecule.

According to a fourth aspect, there is provided a cell which expresses a nucleic acid according to the preceding aspect. The cell is, for example, a cell adapted to express antibody molecules in culture.

The nucleic acid may include signal sequences and/or other sequences or modifications which are required for, or which modulate, sion of the antibody molecule in the cell, and/or secretion of the antibody molecule from the cell.

I n a further embodiment, a humanized antibody is provided as bed in the foregoing aspects, for use in suppressing a T cell mediated response in a subject.

For example, the T cell mediated response can be involved in a condition selected from tissue transplantation, including solid organ transplant and composite tissue transplant, U‘i tissue grafting, le sclerosis and type 1 diabetes.

Moreover, another ment provides a method for treating a subject suffering from a condition involving an aberrant T cell mediated response comprising administering to a subject in need thereof a pharmaceutically effective dose of an antibody according to the described embodiments.

Humanized non-activatory anti-ocBTCR antibodies which do not induce cytokine release have thus been ted which are capable of selective modulation of the ocBTCR and of inducing apoptosis of activated orBTCR positive T cells. These antibodies have been generated for use as immunosuppressive agents in T cell mediated diseases. These antibodies have been generated through humanization of a mouse anti—dBTCR antibody BMA031 and by Fc—engineering of the humanized antibodies to prevent engagement of Fc gamma receptors. The antibodies according to the bed embodiments retain the binding affinity of BMA031, unlike the humanized ns of BMA031 available in the art.

Further, as shown in in vitro education assays, the immunosuppressive properties of dies according to the described embodiments are or to those of BMA031.

Moreover, unlike the humanized BMA031 antibodies of the prior art, the antibodies according to the described embodiments do not induce cytokine release in normal PBMC.

In accordance with a fifth aspect, there is provided an antibody comprising a modified Fc, in which said modified Fc comprises a modified glycosylation pattern which reduces chR or binding, comprising one or more of mutations 8298N, T299A and YBOOS.

In one ment, the antibody comprises two or more of ons N297Q, 8298N, T299A and Y3OOS. ln embodiments, the antibody comprises the multiple mutations 8298N/Y3OOS, S298N/T299A/Y3008 or 8298N/Y3008.

For example, the antibody may be an antibody as bed in ing aspects of the invention.

According to a sixth , there is provided a multispecific antibody comprising at least a heavy chain of a first binding domain as described in the preceding aspects of the invention, and a second binding domain specific for a tumor—specific antigen.

I n one embodiment, the first binding domain comprises a heavy chain according to the U‘i second aspect of the invention.

The multispecific antibody can comprise many different conformations; in one embodiment, it comprises an anti-TCR/CD3 scFv and an anti-tumor scFv.

In one embodiment, the multispecific antibody is bispecific.

Brief Description of the Figures Fig. 1. BMA031 binds more strongly to ocBTCR compared to EuCIV3.

Competition of binding of eled BMAO31 antibody by BMA031 MolgG2b, BMA031 HulgG1 and EuCIV3 Hulth antibodies. EuCIV3 has a decreased potency ed to Fig. 2. EuCIV3 is less potent than BMA031 in an in vitro education (IVE) assay.

Plot showing loss of performance of EuCIV3 humanized antibody in biological assay when compared to parent BMA031 antibody. CD8+ T cells were treated with anti—dBTCR antibodies at various concentrations (X—axis) and tured with autologous tic cells pulsed with the CMV peptide 3 (pp65) for seven days.

Fig. 3. HEBE1 binds ocBTCR comparably to BMA031 in a competition assay.

Competition of binding of PE—labeled BMAO31 antibody by BMA031 Hulth, HEBE1 HulgG1 and EuCIV3 HulgG1 antibodies. EuCIV3 has a sed potency compared to BMA031 and HEBE1.

Fig. 4. HEBE1 has similar potency to EuCIV3 in an in vitro education (IVE) assay.

The IVE assay was performed as described in respect of Fig. 2.

Fig. 5. Schematic showing iterative rounds of mutagenesis of anti-aBTCR variable domains.

Framework in shaded box depicts the F region where certain mouse residues lie.

Shaded residues in first row of mutations are the mouse amino acids that are useful to U‘i maintain off—rate. Shaded residues in second row of mutations are the mouse residues surrounding the CDR regions which were retained during the final germlining process.

Fig. 6. Optimized humanized antibody has ed off-rate compared to BMA031.

The kinetics of antibody dissociation from ocBTCR on T cells was measured by flow BE 1 . cytometry. BMA031 had a better off-rate compared to EuC|V3 and H E By optimizing E BE 1 the binding domain of H we were able to improve the off-rate of HEBE1.H10 compared to BMA031.

Fig. 7. zed humanized antibody has improved off-rate compared to .

The kinetics of antibody dissociation from ocBTCR on T cells was measured by flow cytometry. By optimizing the binding domain of HEBE1 we were able to improve the off- rate of HEBE1.H66 compared to BMA031.

Fig. 8. Optimized humanized dy has improved off-rate compared to BMA031 in both Aab and aglycosylated formats.

The cs of dy dissociation from dBTCR on T cells was measured by flow cytometry.

Fig. 9. Optimization of HEBE1 leads to equivalent onality as BMA031.

IVE assay as described in Fig. 4. BMA031 inhibited education of CD8+ T cells, as they were unable to lyse specific targets in a dose dependent manner. The parental humanized antibody, HEBE1, was not as potent as BMA031 and was able to only inhibit ion at the highest dose (similar results observed with a second non-improved humanized Ab, HEBE1 H13). Further improvements were made to the zed dy, HEBE1 H10, which had equivalent potency to BMA031 in this assay.

Fig. 10. IVE data with anti-aBTCR antibodies.

Both HEBE1 and GL1 BM series antibodies showed improvements in IVE results in comparison with BMA031.

Fig. 11. Antigen positive cells from I assay as determined by antigen-specific tetramer binding.

Cells which are antigen—positive (i.e., have been educated within IV assay) are able to bind to an MHC—tetramer molecule. When the IV assay was conducted in the presence U‘i of antibody which has been able to prevent the education of T cells to antigen, there were fewer cells able to bind to the MHC-tetramer at the end of the assay.

Fig. 12. Proliferation of PBMCs in presence of anti-ocBTCR antibodies, OKT3 and stimulatory beads.

The stimulatory activity of OKT3 was not seen in anti-dBTCR antibodies in this comparison.

Fig. 13. ne release from PBMCs in presence of anti-ocBTCR antibodies.

Cytokine release profile of anti—orBTCR dies was similar to the profile demonstrated by . 4. V E Fig. 1 mma release from T cells in I assay.

CD8+ T cells were treated with anti—dBTCR antibodies at various concentrations (see Fig. 2, x—axis) and co—cultured with autologous dendritic cells pulsed with the CMV peptide 495—503 (pp65) for seven days in an in vitro education (IVE) assay. lFN—gamma release was measured in this assay.

Fig. 15. Activation-induced apoptosis by anti-aBTCR antibodies.

Antigen stimulated CD8+ T cells were induced to apoptosis by g of anti-aBTCR antibodies BMA031 and HEBE1 H66. The ability of HEBE1 H66 to induce apoptosis was increased compared to BMA031.

Fig. 16. Isolation of glycosylation s and aglycosylated dies sie-blue stained gel g expression and purification of glycosylation mutants Fig. 17. Binding of dBTCR antibody mutants to human Fclella using Biacore.

Biacore was used to assess binding to recombinant human Fclella (V158 & F158).

Fig 18. Binding of dBTCR antibody mutants to human Fcle using Biacore.

Biacore was used to assess binding to recombinant human and Fcle.

Fig. 19. Cytokine release from PBMCs in ce of glycosylation mutant anti- ocBTCR antibodies (day 2).

Cytokine release profile for TNFa, GM-CSF, IFNy and |L10 of anti-dBTCR antibodies was similar to the profile demonstrated by BMA031 and H66 delta A Fig. 20. Cytokine release from PBMCs in presence of glycosylation mutant anti- ocBTCR antibodies (day 2).

Cytokine e profile for IL6, |L4 and IL2 of anti-dBTCR antibodies was similar to the e trated by BMA031 and H66 delta AB.

Fig. 21. Cytokine release from PBMCs in presence of glycosylation mutant anti- ocBTCFt antibodies (day 4).

Cytokine release profile for TNFa, GM-CSF, IFNy and |L10 of anti-dBTCR antibodies was similar to the profile demonstrated by BMA031 and H66 delta A Fig. 22. Cytokine release from PBMCs in presence of glycosylation mutant anti- ocBTCR antibodies (day 4). 4 2 Cytokine release profile for lL6, |L and IL of anti—dBTCR antibodies was similar to the e demonstrated by BMA031 and H66 delta AB.

Fig. 23: Binding profiles of TRACERS.

Binding profiles of bi-specific antibodies to both tumor target cells and human T cells assessed by flow cytometery.

Fig. 24: Cytotoxic activity of different T cell recruitment arms.

A panel of humanised BMAO31 antibodies have been created and from this panel a number of antibodies have been selected which y xic activity against tumor antigen sing cell lines Fig. 25: Cytokine release profile of different T cell recruitment arms.

A panel of TRACERs with different T cell recruitment arms show similar cytokine release profiles. Large amounts of cytokines are ed following activation of T cells in the presence of target cells whereas in the presence of only unstimulated human PBMC observed cytokine levels are significantly lower.

Fig. 26: Binding of CD52 antibody mutants to human Fclella using Biacore.

Biacore was used to assess binding of modified anti—CD52 to inant human U] Fclella . Anti-CD52 sing S298N/Y3008 mutations in the Fc domain were used to assess the effector on of the modified molecule. A: binding to CD52 peptide.

B: binding to a (V158). C: control binding to mouse FcRn.

Detailed Description of the Invention Unless otherwise , all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. Any methods and materials similar or equivalent to those described herein can be used in the methods or techniques of the t invention. Al publications pose cited herein are incorporated herein by nce in their entirety for the pur of describing and disclosing the methodologies, reagents, and tools reported in the publications that might be used in connection with the invention.

The methods and techniques of the present application are generally performed according to conventional methods well known in the art and as described in various general and more specific references that are cited and discussed throughout the present ication unless otherwise indicated. See, e.g., Gennaro, A.R., ed. (1990) Remington's Pharmaceutical es, 18th ed., Mack Publishing Co.; Hardman, J.G., Limbird, LE, and Gilman, A.G., eds. (2001) The Pharmacological Basis of Therapeutics, 10th ed., McGraw-Hill Co.; Colowick, S. et al., eds., Methods In Enzymology, Academic Press, Inc.; Weir, D.M. and Blackwell, C.C., eds. (1986) Handbook of Experimental Immunology, Vols. l-lV, Blackwell Scientific Publications; Maniatis, T. et al., eds. (1989) Molecular Cloning: A Laboratory , 2nd edition, Vols. l-lll, Cold Spring Harbor Laboratory Press; Ausubel, FM. et al., eds. (1999) Short Protocols in Molecular Biology, 4th n, John Wiley & Sons; Ream et al., eds. (1998) Molecular Biology Techniques: An Intensive Laboratory Course, Academic Press; Newton, OR. and Graham, A., eds. (1997) PCB (Introduction to Biotechniques Series), 2nd ed., er—Verlag.

A humanized monoclonal antibody, as referred to herein, is an antibody which is ed of a human antibody framework, into which have been grafted complementarity determining regions (CDRs) from a non—human antibody. Changes in the human acceptor framework may also be made. Procedures for the design and production of humanized antibodies are well known in the art, and have been described, for example, in y et a/., U.S. Patent No. 4,816,567; Cabilly et a/., European Patent Application 0 125 023; U‘l Boss et a/., U.S. Patent No. 4,816,397; Boss et al., European Patent Application 0 120 694; Neuberger, MS. ef al., WO 86/01533; ger, MS. et a/., European Patent Application 0 194 276 B1; Winter, U.S. Patent No. 5,225,539; , European Patent Application 0 239 400; Padlan, E.A. eta/., European Patent Application 0 519 596. Further s on antibodies, humanized antibodies, human engineered antibodies, and methods for their preparation can be found in Kontermann, R . and DUbel, S. eds. (2001, 2010) Antibody Engineering, 2nd ed., Springer-Verlag, New York, N The term "antibody", unless ted otherwise, is used to refer to entire antibodies as well as antigen-binding fragments of such antibodies. For example, the term asses encomp four-chain lgG molecules, as well as antibody fragments.

As used herein, the term “antibody fragments” refers to portions of an intact full—length antibody, for example, as further described below.

Antibodies may be of any class, such as lgG, lgA or lgM; and of any subclass, such as lgG1 or lgG4. Different classes and subclasses of globulin have different properties, which may be ageous in different applications. For example, lgG4 2O antibodies have d binding to Fc receptors. icity, in the context of the antibodies described herein, means that the claimed antibody be capable of selectively binding its defined cognate antigen, which is the ocBTCRCDB complex. The antibodies of the invention bind the ocBTCR.CD3 complex expressed on cells.

The human /CD3 complex is the T cell or complex presented on the surface of T cells. See, Kuhns ef al., (2006) Immunity 24:133—139. This complex is targeted by the murine monoclonal antibody BMA031 (see, European patent application EP 0 403 156; SEQ ID NOs: 1 and 2).

Naturally occurring immunoglobulins have a common core ure in which two identical light chains (about 24 kD) and two identical heavy chains (about 55 or 70 kD) form a tetramer. The amino—terminal portion of each chain is known as the variable (V) region and can be distinguished from the more conserved constant (C) regions of the remainder of each chain. Within the le region of the light chain (also called the VL domain) is a C—terminal portion known as the J region. Within the variable region of the heavy chain (also called the VH domain), there is a D region in addition to the J region. Most of the amino acid ce variation in immunoglobulins is confined to three separate locations in the V regions known as hypervariable regions or complementarity determining s U‘l (CDRs) which are directly involved in antigen binding. Proceeding from the amino— terminus, these regions are designated CDR1, CDR2 and CDR3, respectively. The CDRs are held in place by more conserved framework regions (FRs). Proceeding from the amino-terminus, these regions are designated FR1, FR2, FR3 and FR4, respectively. The locations of CDB and F R regions and a numbering system have been defined by Kabat et al. (Kabat, E et a/., ces of Proteins of Immunological Interest, Fifth Edition, US Department of Health and Human Services, US. Government ng Office (1991), and updates thereof which may be found online). In addition, CDR region boundaries have been further defined by IMGT nomenclature.

Variable regions of antibodies according to the described ments may be found in SEQ ID NOs: 5-7 and 12-16, and may be obtained by humanizing BMA031, that is, by transferring the CDRs of BMA031 to a human ork. Two series of humanized E BE 1 antibodies are described; the H series, comprising SEQ ID NOs: 5—7, 12 and 13, and the GL1 BM series, comprising heavy chain le regions as shown in SEQ ID NOS: 8, and 16. In both cases, the light chain variable region used is as shown in SEQ ID NO: 2O 14 (GL1 BM VK43).

The human frameworks used are IGH3-23 in the case of HEBE1, and 3*O1 and IGKV3-11*O1 in the case of GL1 BM. nt regions may be derived from any human antibody nt regions. Variable region genes may be cloned into expression vectors in frame with constant region genes to express heavy and light immunoglobulin chains. Such expression vectors can be transfected into antibody producing host cells for antibody synthesis.

Human antibody variable and constant s may be derived from sequence databases.

For example, immunoglobulin sequences are available in the IMGT/LIGM database (Giudicelli et a/., (2006) Nucleic Acids Res. 34 :(suppl. 1—D784) or VBase (vbase.mrc—cpe.cam.ac.uk).

Aglycosylated antibodies can have extensively modified functionality; see, Boyd et al. (1996) Mol. l. 32:1311-1318. A "delta ab" or Aab modification, referred to herein, is an F0 modification as described in Armour et a/., (1999) Eur. J. Immunol. 292613—2624.

Techniques for modifying glycosylation of antibody Fc regions are known in the art, and e chemical, enzymatic and mutational means, for example, mutation of the N297 position in the CH2 domain. Techniques for mutating antibody genes for producing aglycosylated lgG les are described in Tao and Morrison (1989) J. Immunol. 95-2601.

"Nucleic acids" as referred to herein e D N molecules which encode the antibodies U‘t of the invention. Preferred are expression vectors, which are suitable for expressing the antibody genes in a host cell. sion vectors and host cells for antibody gene expression are known in the art; see, for example, Morrow, K.J. c Engineering & Biotechnology News (June 15, 2008) 28(12), and Backliwal, G. et al. (2008) Nucleic Acids Res. 36(15):e96-e96. 1. Antibodies The invention encompasses antigen-binding nts of the humanized anti-ocBTCR antibodies. Fragments of the antibodies are capable of binding the ocBTCRCDB complex.

They encompass Fab, Fab’, F(ab’)2, and F(v) fragments, or the individual light or heavy chain le regions or portion thereof. Fragments include, for example, Fab, Fab', F(ab')2, Fv and scFv. These fragments lack the Fc portion of an intact antibody, clear more rapidly from the circulation, and can have less non-specific tissue binding than an intact antibody. These fragments can be produced from intact antibodies using well known methods, for example by proteolytic cleavage with s such as papain (to 2O produce Fab fragments) or pepsin (to produce F(ab')2 fragments).

The antibodies and fragments also encomp single—chain antibody fragments (scFv) that bind to the DB complex. An scFv comprises an antibody heavy chain le region (VH) operably linked to an antibody light chain variable region (VL) wherein the heavy chain variable region and the light chain variable region, together or individually, form a g site that binds ocBTCR. An scFv may comprise a VH region at the amino- al end and a VL region at the carboxy-terminal end. Alternatively, scFv may comprise a VL region at the amino-terminal end and a VH region at the carboxy-terminal end. Furthermore, although the two domains of the Fv fragment, VL and VH, are coded for by separate genes, they can be joined, using recombinant methods, by a synthetic linker that enables them to be made as a single protein chain in which the VL and VH regions pair to form monovalent les (known as single chain Fv (scFv)). An scFv may optionally further comprise a polypeptide linker between the heavy chain variable region and the light chain variable region.

The antibodies and nts also encompass domain antibody (dAb) fragments as described in Ward, E.S. et al. (1989) Nature 341:544—546 which consist of a VH domain.

The antibodies and fragments also encompass heavy chain antibodies (HCAb). These antibodies are reported to form antigen—binding regions using only heavy chain variable region, in that these functional antibodies are dimers of heavy chains only (referred to as U‘i "heavy—chain antibodies" or "HCAbs"). Accordingly, antibodies and fragments may be heavy chain antibodies (HCAb) that specifically bind to the ocBTCR.CD3 complex.

The antibodies and fragments also encomp antibodies that are SMlPs or binding domain immunoglobulin fusion proteins specific for ocBTCR.CD3 complex. These constructs are -chain polypeptides comprising antigen-binding domains fused to globulin domains necessary to carry out antibody effector functions (see, WO 17148).

The antibodies and fragments also encompass diabodies. These are bivalent antibodies in which VH and VL domains are expressed on a single polypeptide chain, but using a linker that is too short to allow for pairing between the two domains on the same chain.

This forces the domains to pair with mentary domains of another chain and thereby creates two antigen-binding sites (see, for e. WO 61). Diabodies can be bispecific or monospecific.

The antibody or antibody fragment thereof does not cross-react with any target other than the qBTCRCDB complex.

The antibody or fragment thereof may be ed in order to increase its serum half—life, for example, by adding molecules — such as PEG or other water soluble polymers, including polysaccharide polymers to increase the half—life.

The antibodies and fragments thereof may be bispecific. For example, bispecific antibodies may resemble single antibodies (or antibody nts) but have two different antigen g sites (variable regions). Bispecific antibodies can be produced by various methods — such as al techniques, "polydoma" techniques or recombinant DNA techniques. Bispecific antibodies may have binding specificities for at least two different epitopes, at least one of which is the dBTCRCDB complex. The other specificity may be selected from any useful or desired specificities ing, for example, specificity for human serum albumin for the extension of ife in vivo.

The use of bi-specific antibodies in the clinic for gy ations is now becoming reality with the tri—functional Catumaxomab (Removmab®) ed for use in cases of malignant ascites and the bi—specific antibody Blinatumomab now in phase II trials in hematological malignancies. These molecules have in common a binding arm which binds to T cells and a second arm which binds to the tumor target cell which s in T cell mediated lysis of the tumor target. Also in common, these molecules recruit T cells via the CD3 n located on the cell surface. An alternative to recruitment via CD3 is to make use of the GB T cell receptor (dB TCR) which is also expressed on the surface of the cell.

U‘i Accordingly, antibodies according to the present ion can be used to develop anti— tumor antibodies by combining a specificity for a tumor associated antigen with a icity for the dB T cell receptor (dB TCR). 2. Antibody production The amino acid sequences of the variable s of the antibodies described herein are set forth in SEQ ID NOs: 5-7 and 12-16. Antibody production can be performed by any technique known in the art, ing in transgenic organisms such as goats (see, Pollock et al. (1999) J. Immunol. Methods 231:147-157), chickens (see, , K.J.J. (2000) Genet. Eng. News 20:1-55), mice (see Pollock et al., supra) or plants (see, Doran, P (2000) Curr. Opinion Biotechnol. 11:199—204, Ma. J.K—C. (1998) Nat. Med. 4:601—606, Baez, J. et al. (2000) BioPharm. 13:50—54, Stoger, E. etal. (2000) Plant Mol. Biol. 42:583— 590). Antibodies may also be produced by chemical synthesis or by expression of genes encoding the dies in host cells.

A polynucleotide encoding the antibody is isolated and inserted into a replicable construct 2O or vector such as a plasmid for further propagation or expression in a host cell. Constructs or vectors (e.g., expression vectors) suitable for the expression of a humanized immunoglobulin according to the described embodiments are available in the art. A variety of vectors are available, including vectors which are maintained in single copy or multiple copies in a host cell, or which become integrated into the host cell's chromosome(s). The constructs or vectors can be introduced into a suitable host cell, and cells which express a humanized immunoglobulin can be produced and maintained in culture. A single vector or multiple vectors can be used for the expression of a humanized immunoglobulin.

Polynucleotides encoding the antibody are readily isolated and sequenced using conventional ures (e.g., oligonucleotide probes). Vectors that may be used include plasmid, virus, phage, transposons, romosomes of which plasmids are a typical embodiment. Generally such vectors r e a signal sequence, origin of replication, one or more marker genes, an enhancer element, a promoter and transcription termination sequences operably linked to the light and/or heavy chain cleotide so as to facilitate sion. Polynucleotides encoding the light and heavy chains may be inserted into separate vectors and introduced (e.g., by ormation, ection, electroporation or transduction) into the same host cell concurrently or sequentially or, if desired, both the heavy chain and light chain can be ed into the same vector prior to such introduction.

U‘i A promoter can be provided for expression in a suitable host cell. Promoters can be constitutive or ble. For example, a promoter can be operably linked to a c acid encoding a humanized immunoglobulin or immunoglobulin chain, such that it s expression of the encoded polypeptide. A y of suitable promoters for prokaryotic and eukaryotic hosts are available. Prokaryotic promoters include lac, tac, T3, T promoters for E. coli; 3-phosphoglycerate kinase or other glycolytic enzymes e.g., enolase, glyceralderhyde 3-phosphate dehydrogenase, hexokinase, pyruvate decarboxylase, phosphofructokinase, glucose 6 phosphate isomerase, 3-phosphoglycerate mutase and glucokinase. Eukaryotic promoters include inducible yeast promoters such as l dehydrogenase 2, isocytochrome C, acid atase, metallothionein and enzymes responsible for nitrogen metabolism or maltose/galactose utilization; R polymerase I I promoters including viral promoters such as polyoma, fowlpox and iruses (e.g., adenovirus 2), bovine papilloma virus, avian sarcoma virus, cytomegalovirus (in particular, the immediate early gene promoter), irus, tis B virus, actin, rous sarcoma virus (RSV) promoter and the early or late Simian virus 40 and non-viral promoters such as EF- 2O 1 alpha (Mizushima and Nagata (1990) Nucleic Acids Res. 18(17):5322). Those of skill in the art will be able to select the appropriate promoter for expressing a humanized antibody or portion thereof.

Where appropriate, e.g., for expression in cells of higher eukaroytes, additional er elements can be included instead of or as well as those found located in the promoters described above. Suitable mammalian enhancer sequences include enhancer elements from globin, elastase, albumin, otein, metallothionine and insulin. Alternatively, one may use an enhancer element from a eukaryotic cell virus such as SV4O enhancer, cytomegalovirus early promoter enhancer, polyoma enhancer, baculoviral enhancer or murine lgG2a locus (see, WO 04/009823). Whilst such ers are often d on the vector at a site upstream to the promoter, they can also be located elsewhere e.g., within the untranslated region or downstream of the polyadenylation signal. The choice and positioning of enhancer may be based upon compatibility with the host cell used for expression.

In addition, the vectors (9.9., expression vectors) may comprise a selectable marker for selection of host cells carrying the vector, and, in the case of a replicable vector, an origin of replication. Genes encoding products which confer antibiotic or drug resistance are common able markers and may be used in prokaryotic (e.g., f3—lactamase gene (ampicillin resistance), Tet gene (tetracycline resistance) and eukaryotic cells (9.9., neomycin (G418 or geneticin), gpt (mycophenolic acid), ampicillin, or hygromycin U‘i resistance . Dihydrofolate reductase marker genes permit selection with methotrexate in a variety of hosts. Genes encoding the gene product of auxotrophic markers of the host (e.g., LEU2, URAB, HISS) are often used as selectable markers in yeast. Use of viral (e.g., baculovirus) or phage vectors, and vectors which are capable of integrating into the genome of the host cell, such as retroviral vectors, are also plated.

I n eukaryotic systems, polyadenylation and termination signals are ly linked to polynucleotide encoding the antibody of the invention. Such signals are typically placed 3' of the o reading frame. In mammalian systems, non-limiting examples of polyadenylation/termination signals include those derived from growth hormones, elongation factor-1 alpha and viral (e.g., SV40) genes or retroviral long terminal repeats.

I n yeast systems, non—limiting examples of polydenylation/termination signals include those derived from the phosphoglycerate kinase (PGK) and the alcohol dehydrogenase 1 (ADH) genes. In prokaryotic systems polyadenylation s are lly not required and it is instead usual to employ r and more defined terminator sequences. The 2O choice of polyadenylation/termination sequences may be based upon compatibility with the host cell used for expression. In addition to the above, other features that can be employed to enhance yields e chromatin remodeling elements, introns and host cell specific codon modification. The codon usage of the antibodies of the invention can be modified to accommodate codon bias of the host cell such to augment ript and/or product yield (9.9., Hoekema, A. et al. (1987) Mol. Cell Biol. 914-24). The choice of codons may be based upon compatibility with the host cell used for expression.

The invention thus relates to isolated nucleic acid molecules that encode the humanized immunoglobulins, or heavy or light chains, thereof. The invention also s to isolated nucleic acid molecules that encode an antigen—binding portion of the immunoglobulins and their chains.

The antibodies can be produced, for e, by the expression of one or more recombinant nucleic acids encoding the antibody in a le host cell. The host cell can be produced using any suitable method. For e, the expression constructs (e.g., one or more vectors, 9.9., a mammalian cell expression vector) described herein can be introduced into a suitable host cell, and the resulting cell can be maintained (e.g., in e, in an animal, in a plant) under ions suitable for expression of the construct(s) or vector(s). Host cells can be prokaryotic, including bacterial cells such as E. coli (e.g., strain DH5aTM) (lnvitrogen, Carlsbad, CA), PerC6 (Crucell, Leiden, NL), B. subti/is and/ other suitable bacteria; eukaryotic cells, such as fungal or yeast cells (e.g., U‘i Pichia pastor/s, Aspergillus sp., Saccharomyces cerevisiae, Schizosaccharomyces pombe, Neurospora crassa), or other lower otic cells, and cells of higher eukaryotes such as those from insects (e.g., Drosophi/a der 82 cells, St9 insect cells) (WO 94/126087 (O'Connor)), BTl-TN-SB1-4 (High FiveT'V') insect cells (lnvitrogen), mammals (e.g., COS cells, such as COS-1 (ATCC Accession No. CRL-1650) and COS-7 (ATCC Accession No. CRL-1651), CHO (e.g., ATCC Accession No. CRL-9096), CHO DG44 (Urlaub, G. and Chasin, L (1980) Proc. Natl. Acad. Sci. USA, 77(7):4216-4220), 293 (ATCC Accession No. CRL-1573), HeLa (ATCC ion No. COL-2), CVl (ATCC Accession No. COL-70), WOP (Dailey, L., et al. (1985) J. Virol., 54:739-749), 3T3, 293T (Pear, W.S., et al. (1993) Proc. Natl. Acad. Sci. USA, 90:8392—8396), NSO cells, SP2/ cells, HuT 78 cells, and the like, or plants (e.g., tobacco, lemna (duckweed), and algae).

See, for example, Ausubel, F M et al., eds. Current Protocols in Molecular Biology, Greene Publishing Associates and John Wiley & Sons Inc. (1993). I n some embodiments, the host cell is not part of a multicellular organism (e.g., plant or animal), e.g., it is an isolated host cell or is part of a cell e. 2O Host cells may be cultured in spinner flasks, shake flasks, roller bottles, wave rs (e.g., System 1000 from otechcom) or hollow fibre systems but it is preferred for large scale production that stirred tank reactors or bag reactors (e.g., Wave h, Somerset, New Jersey USA) are used particularly for suspension cultures. Stirred tank rs can be adapted for aeration using e.g., spargers, baffles or low shear impellers.

For bubble columns and airlift rs, direct aeration with air or oxygen bubbles maybe used. Where the host cells are cultured in a serum-free culture medium, the medium can be supplemented with a cell protective agent such as pluronic F—68 to help prevent cell damage as a result of the aeration process. Depending on the host cell characteristics, microcarriers maybe used as growth substrates for age dependent cell lines, or the cells maybe adapted to suspension culture. The culturing of host cells, particularly vertebrate host cells, may utilize a variety of operational modes such as batch, fed—batch, repeated batch processing (see, Drapeau et al. (1994) Cytotechnology 15:103—109), ed batch process or perfusion culture. gh recombinantly transformed mammalian host cells may be cultured in serum—containing media such media comprising fetal calf serum (FCS), it is preferred that such host cells are cultured in serum—free media such as disclosed in Keen et al. (1995) Cytotechno/ogy —163, or commercially available media such as ProCHO—CDM or UltraCHOT'V' (Cambrex NJ, USA), supplemented where necessary with an energy source such as glucose and synthetic growth factors such as recombinant insulin. The serum—free culturing of host cells may require that those cells are adapted to grow in serum—free ions. One tion U‘l approach is to culture such host cells in serum containing media and repeatedly exchange 80% of the culture medium for the serum-free media so that the host cells learn to adapt in serum-free conditions (see, e.g., Scharfenberg, K. etal. (1995) Animal Cell Technology: pments Towards the 21st y (Beuvery, E.C. et al., eds), pp.619-623, Kluwer Academic publishers).

Antibodies according to the described embodiments may be secreted into the medium and red and purified therefrom using a variety of techniques to provide a degree of purification suitable for the intended use. For example, the use of therapeutic antibodies for the treatment of human patients typically mandates at least 95 purity as ined % % by reducing SDS-PAGE, more typically 98 or 99 purity, when compared to the culture media comprising the therapeutic antibodies. In the first instance, cell debris from the e media can be removed using centrifugation followed by a clarification step of the supernatant using e.g., iltration, ultrafiltration and/ depth filtration. Alternatively, the antibody can be harvested by microfiltration, ultrafiltration or depth filtration without prior centrifugation. A variety of other techniques such as is and gel ophoresis 2O and chromatographic techniques such as hydroxyapatite (HA), affinity tography (optionally involving an affinity tagging system such as polyhistidine) and/or hydrophobic interaction Chromatography (HIC) (see, US 5,429,746) are available. In one embodiment, the antibodies, following various clarification steps, are ed using Protein A or G affinity chromatography followed by further chromatography steps such as ion exchange and/or HA chromatography, anion or cation exchange, size ion chromatography and ammonium sulphate precipitation. Various virus removal steps may also be employed (e.g., nanofiltration using, e.g., a DV—20 filter). Following these various steps, a purified preparation comprising at least 10 mg/ml or greater, e.g., 100 mg/ml or greater of the antibody of the invention is provided and, therefore, forms another embodiment of the invention. Concentration to 100 mg/ml or greater can be generated by ultracentrifugation.

Such preparations are ntially free of aggregated forms of antibodies of the ion.

Bacterial systems are particularly suited for the expression of antibody fragments. Such fragments are zed intracellularly or within the periplasm. Insoluble asmic proteins can be extracted and refolded to form active proteins according to methods known to those skilled in the art, see, Sanchez etal. (1999) J. Biotechnol. 72:13—20; Cupit, P M etal. (1999) Lett. Appl. Microbiol. 29:273—277.

The t invention also relates to cells sing a nucleic acid, e.g., a vector, of the invention (e.g., an expression vector). For example, a c acid (i.e., one or more U‘i nucleic acids) encoding the heavy and light chains of a humanized globulin ing to the described embodiments, or a uct (i.e., one or more constructs, e.g., one or more vectors) comprising such nucleic ), can be uced into a suitable host cell by a method appropriate to the host cell selected (e.g., transformation, transfection, electroporation, infection), with the nucleic acid(s) being, or becoming, operably linked to one or more expression control elements (9.9., in a vector, in a construct created by processes in the cell, integrated into the host cell genome). Host cells can be maintained under conditions suitable for expression (9.9., in the presence of inducer, suitable media supplemented with appropriate salts, growth factors, antibiotic, nutritional supplements, etc), whereby the encoded polypeptide(s) are ed. I f desired, the encoded humanized antibody can be isolated, for example, from the host k . asses cells, culture medium, or mil This s encomp sion in a host cell (9.9., a mammary gland cell) of a transgenic animal or plant (e.g., tobacco) (see, e.g., WO 92/03918). 3. Therapeutic Applications Suppression of T cell activity is desirable in a number of situations in which immunosuppression is warranted, and/or an autoimmune condition occurs. Accordingly, targeting of the dBTCR.CD3 complex is indicated in the treatment of es involving an inappropriate or red immune response, such as inflammation, autoimmunity, and other conditions involving such mechanisms. In one embodiment, such disease or disorder is an mune and/or inflammatory disease. Examples of such autoimmune and/or inflammatory diseases are ic Lupus Erythematosus (SLE), Rheumatoid Arthritis (RA) and inflammatory bowel disease (IBD) (including ulcerative colitis (U0) and Crohn's disease (CD)), multiple sclerosis (MS), scleroderma and type 1 diabetes (T1D), and other diseases and disorders, such as PV (pemphigus vulgaris), psoriasis, atopic dermatitis, celiac disease, Chronic Obstructive Lung disease, Hashimoto's thyroiditis, Graves' disease (thyroid), Sjogren’s me, Guillain—barré syndrome, Goodpasture's syndrome, Addison's disease, Wegener's granulomatosis, primary biliary sclerosis, sclerosing cholangitis, autoimmune hepatitis, polymyalgia rheumatica, Raynaud's enon, temporal arteritis, giant cell arteritis, autoimmune hemolytic anemia, pernicious anemia, teritis nodosa, behcet‘s disease, primary bilary sis, uveitis, myocarditis, rheumatic fever, ankylosing spondylitis, glomerulenephritis, sarcoidosis, dermatomyositis, myasthenia gravis, polymyositis, alopecia areata, and vitilgo.

BD .

I n one embodiment, such disease or disorder is SLE, R A or I In one embodiment, U‘i such disease or disorder is MS.

In another embodiment, the antibodies according to the described embodiments are used to aid transplantation by immunosuppressing the subject. Such use alleviates graft- versus-host e. For a description of existing treatments for versus-host disease, see , e.g., Svennilson, Bone Marrow Transplantation (2005) —867, and references cited therein. Advantageously, the antibodies of the invention may be used in combination with other available therapies.

With regard to the treatment of autoimmune diseases, combination therapy may include administration of an antibody of the present invention together with a medicament, which together with the antibody comprises an effective amount for ting or ng such autoimmune diseases. Where said autoimmune disease is Type 1 es, the combination therapy may encomp one or more of an agent that promotes the growth of atic beta—cells or enhances beta—cell transplantation, such as beta cell growth or survival factors or immunomodulatory dies. Where said mune disease is rheumatoid arthritis, said combination therapy may encompass one or more of rexate, an anti—TNF—B antibody, a TNF—B receptor—lg fusion protein, an anti—IL—15 or anti—lL—21 antibody, a non—steroidal anti—inflammatory drug (NSAID), or a disease— modifying anti—rheumatic drug (DMARD). For example, the additional agent may be a biological agent such as an anti-TNF agent (e.g., Enbrel®, imab (Remicade®) and adalimumab a®) or rituximab (Rituxan®). Where said autoimmune disease is hematopoietic transplant rejection, poietic growth factor(s) (such as erythropoietin, G—CSF, GM—CSF, IL—3, IL—11, thrombopoietin, etc.) or antimicrobial(s) (such as antibiotic, antiviral, antifungal drugs) may be administered. Where said autoimmune disease is psoriasis, the additional agent may be one or more of tar and derivatives thereof, phototherapy, corticosteroids, Cyclosporine A, vitamin D analogs, methotrexate, p38 mitogen—activated protein kinase (MAPK) inhibitors, as well as biologic agents such as anti—TNF— agents and Rituxan® . Where said autoimmune disease is an inflammatory bowel disease (IBD) such as, for example, Crohn's Disease or ulcerative colitis, the additional agent may be one or more of aminosalicylates, corticosteroids, immunomodulators, antibiotics, or biologic agents such as Remicade® and Humira®.

The combination treatment may be carried out in any way as deemed ary or convenient by the person skilled in the art and for the purpose of this specification, no limitations with regard to the order, amount, repetition or relative amount of the compounds to be used in combination is contemplated. Accordingly, the antibodies U‘i according to the described embodiments may be formulated into pharmaceutical compositions for use in therapy. 4. Pharmaceutical Compositions In a preferred embodiment, there is provided a pharmaceutical composition comprising an antibody ing to the invention, or a ligand or ligands identifiable by an assay method as defined in the previous aspect of the invention. Ligands may be immunoglobulins, peptides, nucleic acids or small molecules, as discussed herein. They are referred to, in the ing discussion, as “compounds”.

A ceutical composition according to the invention is a ition of matter comprising a compound or compounds capable of modulating T cell activity as an active ingredient. The nd is in the form of any pharmaceutically acceptable salt, or e.g., where appropriate, an analog, free base form, tautomer, enantiomer racemate, or combination thereof. The active ients of a pharmaceutical composition comprising the active ingredient according to the invention are contemplated to exhibit therapeutic activity, for example, in the treatment of graft-versus-host disease, when administered in 2O amount which depends on the particular case.

In another ment, one or more compounds of the ion may be used in combination with any art recognized compound known to be suitable for ng the particular indication in treating any of the aforementioned conditions. Accordingly, one or more compounds of the invention may be combined with one or more art ized compounds known to be suitable for treating the foregoing indications such that a convenient, single composition can be administered to the subject. Dosage regima may be ed to provide the optimum therapeutic response.

For example, several divided doses may be administered daily or the dose may be proportionally reduced as indicated by the exigencies of the therapeutic ion.

The active ingredient may be administered in a convenient manner such as by the oral, intravenous (where water soluble), intramuscular, subcutaneous, intranasal, intradermal or suppository routes or implanting (9.9., using slow release molecules).

Depending on the route of administration, the active ingredient may be required to be coated in a material to protect said ients from the action of enzymes, acids and other natural conditions which may inactivate said ingredient.

I n order to administer the active ient by means other than eral administration, U‘l it will be coated by, or administered with, a material to prevent its inactivation. For example, the active ingredient may be administered in an adjuvant, co-administered with enzyme inhibitors or in liposomes. nt is used in its broadest sense and includes any immune stimulating compound such as interferon. Adjuvants contemplated herein include resorcinols, non-ionic tants such as yethylene oleyl ether and n-hexadecyl polyethylene ether. Enzyme inhibitors include atic trypsin.

Liposomes include water-in-oil-in-water CGF emulsions as well as conventional liposomes.

The active ingredient may also be administered parenterally or intraperitoneally. sions can also be prepared in ol, liquid hylene glycols, and mixtures thereof and in oils. Under ordinary conditions of storage and use, these preparations contain a preservative to prevent the growth of microorganisms.

The pharmaceutical forms suitable for injectable use include sterile aqueous solutions (where water soluble) or dispersions and sterile powders for the extemporaneous preparation of sterile injectable solutions or dispersion. In all cases the form must be sterile and must be fluid to the extent that easy syringability exists. It must be stable under the conditions of manufacture and storage and must be preserved against the contaminating action of microorganisms such as bacteria and fungi. The carrier can be a solvent or dispersion medium containing, for example, water, ethanol, polyol (for example, glycerol, ene glycol, and liquid polyethylene glycol, and the like), suitable mixtures thereof, and vegetable oils. The proper fluidity can be maintained, for example, by the use of a g such as lecithin, by the maintenance of the required particle size in the case of dispersion and by the use of superfactants.

The prevention of the action of microorganisms can be brought about by various antibacterial and ngal agents, for example, parabens, chlorobutanol, phenol, sorbic acid, thirmerosal, and the like. In certain cases, it may be preferable to include isotonic agents, for example, sugars or sodium chloride. Prolonged absorption of the injectable compositions can be brought about by the use in the compositions of agents delaying absorption, for example, aluminium monostearate and gelatin.

Sterile able solutions are prepared by incorporating the active ingredient in the required amount in the appropriate solvent with several of the other ingredients U‘i enumerated above, as required, followed by ed sterilization. Generally, dispersions are prepared by incorporating the sterilized active ingredient into a sterile vehicle which contains the basic dispersion medium and the required other ingredients from those enumerated above. In the case of sterile powders for the preparation of sterile injectable solutions, the preferred methods of preparation are vacuum drying and the freeze-drying que which yield a powder of the active ingredient plus any additional desired ingredient from usly sterile-filtered solution thereof.

Various other als may be t as coatings or to otherwise modify the physical form of the dosage unit. Of , any material used in preparing any dosage unit form should be pharmaceutically pure and substantially non-toxic in the amounts employed. In addition, the active ingredient may be incorporated into sustained—release ations and formulations.

As used herein "pharmaceutically acceptable r and/or diluent" includes any and all solvents, dispersion media, coatings, antibacterial and antifungal agents, isotonic and tion delaying agents and the like. The use of such media and agents for 2O pharmaceutical active substances is well known in the art. Except insofar as any conventional media or agent is incompatible with the active ingredient, use thereof in the therapeutic compositions is contemplated. Supplementary active ingredients can also be incorporated into the compositions.

It is especially advantageous to formulate parenteral compositions in dosage unit form for ease of administration and mity of dosage. Dosage unit form as used herein refers to physically discrete units suited as unitary dosages for the mammalian subjects to be treated; each unit containing a predetermined quantity of active material calculated to produce the desired therapeutic effect in association with the required pharmaceutical carrier. The specification for the novel dosage unit forms of the invention are dictated by and ly dependent on (a) the unique characteristics of the active al and the particular therapeutic effect to be achieved, and (b) the limitations inherent in the art of nding such as active material for the treatment of disease in living subjects having a diseased condition in which bodily health is impaired.

The principal active ingredients are compounded for convenient and effective administration in ive amounts with a suitable pharmaceutically acceptable r in dosage unit form. In the case of compositions containing supplementary active ingredients, the dosages are determined by reference to the usual dose and manner of U‘l administration of the said ingredients.

In order to facilitate delivery of peptide compounds, including antibodies, to cells, peptides may be ed in order to improve their ability to cross a cell membrane. For example, US 5,149,782 discloses the use of fusogenic peptides, ion-channel forming peptides, membrane peptides, hain fatty acids and other membrane blending agents to increase n transport across the cell membrane. These and other methods are also 37016 described in WO 97/ and US 5,108,921, incorporated herein by reference.

I n a further aspect there is provided the active ingredient of the invention as hereinbefore defined for use in the treatment of disease either alone or in combination with art recognized compounds known to be suitable for treating the particular indication.

Consequently there is provided the use of an active ient of the invention for the manufacture of a medicament for the treatment of disease associated with an aberrant ponse. immune res Moreover, there is provided a method for treating a condition ated with an aberrant immune response, comprising administering to a subject a therapeutically 2O ive amount of a ligand identifiable using an assay method as described above.

The invention is further described, for the purposes of illustration only, in the ing examples.

Comparative Example 1 Binding and biological activity of EuCIV3 is decreased compared with BMA031 Using flow cytometry, we have shown that EuCIVS is inferior to BMA031 in T cell binding (Fig. 1). In this competition assay, T cells were incubated on ice in the presence of a fixed concentration of directly Phycoerythrin—labeled MolgG2b—BMAO31 (murine competitor) and an increasing concentration of anti—dBTCR antibodies. After 20 minutes incubation, the cells were washed and surface bound directly Phycoerythrin—labeled MolgG2b— BMA031 was detected by flow cytometry. The BMA031 HulgG1 ic antibody competes much more effectively than EuClV3.

In order to assess its ability to inhibit T cell ty in vivo, CD8+ T cells were treated with anti—dBTCR antibodies at s concentrations (see, Fig. 2, x—axis) and co—cultured with autologous dendritic cells (DCs) pulsed with the CMV peptide 495—503 (pp65) for seven days in an in vitro education (IVE) assay.

Normal donor aphaeresis products from + individuals were obtained from HemaCare Corp., Van Nuys, CA). PBMC were isolated by centrifugation over Ficoll (GE U‘i Healthcare, Piscataway, NJ). CD8+ T cells were isolated using magnetic beads (lnvitrogen, Carlsbad, California) ing to the manufacturer’s ctions. To generate autologous immature tic cells, PBMC were resuspended in RPMI 1640/5% human AB serum (Sigma), plated in triple flasks (Corning) and ted for more than 2 hours at 37°C/5%C02. The adherent monocytes were then rinsed with PBS and cultured P M I / 5% B for 6 days in R 1640 human A serum supplemented with GM-CSF (lmmunex, -4 /DC Seattle, WA) and lL (PeproTech, Rocky Hill, NJ). Prior to establishing the T cell co- cultures, the DCs were pulsed with peptides (10ug/ml) for 4 hours and then matured.

Mature dendritic cells were generated by the addition of 50ng/ml TNF-alpha, 25ng/ml lL- 1B, l lL-6, 500ng/ml PGE-2 (PeproTech, Rocky Hill, NJ) and culturing the dendritic cells for an additional 24 hours. The e-pulsed DCs were then added to the previously isolated CD8+ T cells at a T:DC ratio of 10:1. Cultures were immediately fed with lL-2 (100 lU/ml) added to the cultures. The cultures were supplemented with lL-2 (100 lU/ml) on day 4. The bulk cultures were assayed for peptide reactivity in a chromium release assay on day 7. 2O The graph in Fig. 2 shows lysis data from the chromium release assay, where untreated T cells were successfully educated against pp65 e and able to lyse specific targets at >50%. BMA031 inhibited education of these T cells, as they were unable to lyse specific targets in a dose—dependent manner. Humanized dy EuClV3 was less potent than BMAO31 and was only able to inhibit education at the highest dose.

Example 2 Fc Engineering of BMA031 chimeric antibodies In vitro profile We have assessed the in vitro profile of BMA031 in a panel of assays. Table 1 shows the in vitro profile of BMA031. BMA031 is compared to OKT3 in these assays.

In the PBMC eration assay, human PBMC were cultured with increasing concentrations of therapeutic antibody for 72 hours, 3H-thymidine was added and cells were harvested 18 hours later.

For the T cell depletion/Cytokine Release assay, human PBMC were ed with increasing concentrations of therapeutic antibody and were analyzed daily for cell counts and viability (Vi—Cell, n Coulter) out to day 7. Cell supernatants were also harvested, stored at 2000 and analyzed on an 8—plex cytokine panel (Bio—Rad).

BMA031 does not induce: (i) PBMC proliferation; (ii) T cell depletion; (iii) CD25 expression; or (iv) cytokine e. In contrast, OKT3 does induce all of the U‘l aforementioned effects. BMA031 and OKT3 are e of blocking the education of CD8+ cells to peptide in an in vitro education (IVE) assay and are also e of blocking a mixed cyte reaction (MLR). BMA031 also induces apoptosis of activated T cells (activation-induced cell death; AICD).

Unlike BMA031, a chimeric version of BMA031 (HulgG1), with wild-type human IgG1 constant region, had an in vitro profile comparable to OKT3 (Table 1). We postulated that FcyR involvement was critical for this change of in vitro profile for HulgG1 BMA031 ed to BMA031 MolgGZb. Therefore we made F(ab’)2 fragments of BMAO31 HulgG1 and found these to recover the profile of BMA031 MolgG2b. By Fc engineering we incorporated modifications that removed FcyR binding in mutations known as “delta ab” (Armour ef al. (1999) Eur. J. Immunol., 292613—2624) and by generating an aglycosylated form of HulgG4 ). HulgG1 delta ab and HulgG4 agly anti-dBTCR antibodies had the same in vitro profile as BMAO31 MolgG2b (Table 1).

Normal PBMC Antigen Activated T-cells TSTCR uflTCR FcyR PBMC CD25 Cylokine MLR Apoptosis/ IVE Depletion binding binding binding Proliferation Expression Inhibition Inhibition OKT3 BMAO31 b BMA031 HulgG1 BMA031 F(ab)2 BMA031 Aab HulgG1 HEBE1 Aab HulgG1 HEBE1 |gG4 agly Table 1 Example 3 Construction of humanized antibodies with improved g We have generated two series of humanized versions of BMAO31 called HEBE1 series (IGH3—23) and GL1BM series (IGHV1—3*01 & |GKV3—11*01; see, VBase, vbase.mrc— cpe.cam.ac.uk). Initial ng of BMA031 heavy chain CDR regions onto IGH3—23 ork regions (see, SEQ ID NOs: 5 and 6) improved the binding of the antibody to the ocBTCR as shown by a competition assay (Fig. 3); see, e 2. r, this improvement did not translate into a functional improvement in the antibody as shown by an IV assay (Fig. 4).

Example 4 Optimization of humanized antibodies The strategy for optimization of the humanized antibodies was based u nesis and functional ing. Optimization was started with block changes of amino acid residues in one of each of the four framework regions of the variable domains, from mouse to human. Key framework regions were fied in each of the GL1BM HC, BE 1 GL1 B M LC and H E HC series. Following this identification, individual residues within those framework regions were mutated to human germline residues from the original mouse ce. Framework residues for which identity with the mouse sequence was found to be important to retaining the binding properties of the antibody were retained as mouse residues. Otherwise, framework residues were changed to match the human germline amino acid sequence. This was continued across the sequence until the minimal number of mouse residues, to retain the original binding properties of the antibody, were identified. See Fig. 5. We have demonstrated that several of the antibodies from these series have an improved binding compared to BMA031 as 2O determined by antibody off-rate from T cells (Figs. 6, 7 and 8).

For off—rate assays, 105 human T cells were incubated for 30—60 minutes at room temperature in 100uL full growth media containing 2ug/mL of the antibodies expressed as HulgG1—Aab. The cells were then , resuspended in 50uL full growth media and 20ug/mL of HEBE1 F(ab’)2 was added in order to t the ing of the dissociated candidate antibodies. At the end of this time course assay, the cells were fixed and the level of remaining HulgG1—Aab antibody bound to the cell surface was ed by flow cytometry via a PE labeled goat anti-HulgG secondary antibody.

We have also demonstrated that the antibodies are active in preventing the immune response in an IVE (Figs. 9, 10 and 11) and a MLR assay. In the IVE assay, er binding was used as a quantitative measurement for the IVE. The percentage of cells which were antigen specific was determined by staining the T cells with a directly labeled tetramer that is specific for the educating peptide. Briefly, day 7 CD8+ T cells from the IVE were stained with tetramer by standard flow cytometry staining ols and analyzed on B D FACSCaIibur. I n addition, the humanized antibodies demonstrated comparable levels of erative potential on PBMCs and cytokine release as compared to BMA031 (Figs. 12 and 13).

The antibodies also showed an ability to inhibit the release of IFNytrom T cells in an IV U‘l assay (Fig. 14). In addition we have shown that a number of these antibodies have an improved ability to elicit activation-induced cell death (AICD) of ted ocBTCR-positive T cells compared to BMA031 (Fig. 15). In the AICD assay, antigen-specific CD8+ T cells were cultured with therapeutic antibody. At 24 hours, 48 hours and 72 hours cells were stained for apoptosis markers Annexin-V and 7-AAD. Cells were also stained with tetramer to track sis with effects on antigen-specific T cells.

In conclusion, we have made significant improvement over previous attempts to humanize BMA031. The discovery of antibodies with an improved off-rate compared to BMA031 is an unexpected finding via this process. This ement in binding correlates with an improvement in potency to suppress an immune response as demonstrated in the IVE assay (Figs. 10 and 11). The specificity of the antibodies for ocBTCR, the decreased genicity by humanization, the specific apoptosis of activated T cells and the lack of T cell activation u antibody binding make these antibodies excellent candidates for poses. therapeutic pur Example 5 Generation of Fc mutants for reduced effector function. ered Fc variants was designed and generated where a glycosylation site is introduced at amino acid Ser 298 position, next to the naturally—occurring Asn297 site. The ylation at Asn297 was either kept or knocked out by mutations. Mutations and glycosylation results are set forth in Table 2.

# Mutation Predicted result Expected t 1 N297Q No glycosylation Agly Control No glycosylation Agly Control, 2 T299A unknown effector function No glycosylation at 297 but Reduced effector N297Q/8298N/Y3008 3 engineered glycosylation SiteI I I functionI (NSY) at 298 No glycosylation at 297 but Reduced effector 8298N/T299A/Y3008 4 engineered glycosylation SiteI I I functionI (STY) at 298 Two potential glycosylation Positive control for sites at 297 & 298; Double reduced effector Y3008 S298N/ (SY) glycosylation?I Mixed I functionI glycosylation? Table 2 ons were made on the heavy chain of (18 T—cell receptor antibody clone #66 by H E BE 1 Quikchange using a pENTRiLICiIgG1 template. The V domain of H Aab |ng #66 was amplified with LIC primers, and cloned into mutated or wild type pENTR_L|C_IgG1 by LIC to create a full—length Ab mutants or wild type. The subcloning was verified with Dralll/Xhol double digest, producing ~125O bp insert in the successful clones. Those full—length s were then cloned into an expression vector, pCEP4(—E+|)Dest, via Gateway cloning. The ons were then confirmed by DNA sequencing.

Two constructs, HEBE1 Agly lgG4 and HEBE1 Aab lng in pCEP4, were used as controls in H EK293 transfection.

The mutants, wt and controls (Agly and Aab) were transfected into —EBNA cells in triple—flask for expression. Proteins were ed from 160 ml of conditioned media (GM) with 1 ml HiTrap protein A columns (GE) on hannel peristaltic pump. Five micrograms of each atant were analyzed on 4—20 Tris—Glycine reducing and non— reducing SDS—PAGE (see Figure 16). The heavy chain of the aglycosylated mutants (N297Q, T299A, and Agly l, is lower (arrow in black), consistent with the loss of the s in these antibody. The heavy chains of the engineered glycosylated antibodies U‘l (NSY, STY, SY, Aab, and wt control, arrows in red), however, migrate the same way as the ype control. This result is consistent with the ed outcome of engineered glycosylation site at 298 positions. SEC-HPLC analysis indicated that all mutants are expressed as monomers.

G/ycosy/ation analysis by LC-MS.

The ered H66 lgG1 Fc variants were partially reduced with 20mM D T at 37°C for min. The samples were analyzed by capillary LC/ on an Agilent 1100 capillary HPLC system coupling with a QSTAR qq TOF hybrid system (Applied Biosystem).

Bayesian protein truct with ne correction and er modeling in Analyst T299A/ Y3008 08 1.1 ed Bisoystem) was used for data analysis. For mutant S298N/ H66 antibody lead, one glycosylation site was ed at amino acid 298 with bi— antennary and tri— antennary complex—type glycans detected as the major species, as well as GOF, G1 F and (32F.

Binding of (1,8 TCR antibody mutants to human FcyR/lla and Fcle using Biacore.

Biacore was used to assess binding to recombinant human Fclella (V158 & F158) and 2O Fcle. All 4 flowcells of a CM5 chip were immobilized with anti-HPC4 antibody via the standard amine coupling procedure provided by Biacore. The anti—HPC4 antibody was diluted to 50ug/mL in 10mM sodium acetate pH 5.0 for the coupling reaction and injected for 25 min at 5uL/min. Approximately 12,000 RU of antibody was immobilized to the chip surface. Recombinant human Fclella-V158 and Fclella-F158 were diluted to 0.6ug/mL in binding buffer, HBS—P with 1mM CaClg, and injected to flowcells 2 and 4, respectively, for 3 min at 5uL/min to capture 300 — 400 RU receptor to the anti-HPC4 chip. In order to distinguish between the low binders, three times more la was captured to the PC4 surface than usually used in this assay. Flowcells 1 and 3 were used as reference controls. Each antibody was diluted to 200nM in binding buffer and injected over all 4 flowcells for 4 min, followed by 5 min dissociation in butter. The surfaces were regenerated with 10mM EDTA in HBS—EP butter for 3 min at 20uL/min.

The results are shown in Figure 17.

Biacore was also used to e the chRI binding. Anti—tetra His antibody was buffer exchanged into 10mM sodium acetate pH 4.0 using a Zeba ing column and diluted to 25ug/mL in the acetate buffer for amine coupling. Two flowcells of a CM5 chip were immobilized with ~9000 RU of the anti—Tetra—His antibody after 20 min injection at U‘i 5uL/min. r to the us experiment, ten times more Fcle was captured to the anti-tetra-His surface in order to compare weak binders. Recombinant human chRl was diluted foug/mL in HBS—EP binding buffer and injected to flowcell 2 for 1 min at 5uL/min to capture ~1000 RU receptor to the anti-tetra-His chip. A single concentration of antibody, 100nM, was injected for 3 min at 30uL/min over the captured receptor and control surface. Dissociation was monitored for 3 min. The e was regeneration with two 30 sec injections of 10mM glycine pH 2.5 at 20uL/min.

The results are shown in Figure 18.

The result suggests very little binding of the glycoengineered mutants to chRllla or T299A/ YSOOS Fcle. H66 8298N/ in particular has almost completely abolished binding to both receptors. This mutant was chosen as the lead for ed characterization.

Stability characterization using Circular Dichroism (CD).

The stability of the S298N/T299A/Y3008 antibody mutant was monitored by a Far—UV CD thermo melting experiment where the CD signal at 216nm and 222nm was monitored as temperature increases that eventually leads to the unfolding of the antibody. The CD 2O spectra were collected on a Jasco 815 ophotometer at a protein concentration of imately 0.5 mg/mL in PBS buffer in a quartz cuvette (Hellma, Inc) with a path length of 10 mm. Temperature was controlled by a thermoelectric peltier (Jasco model AWCtOO) and was ramped at a rate of 1°C/min from 25-89 °C. CD signal and HT voltage were both collected. Data was obtained from 210-260 nm with data intervals of 0.5 nm and at temperature intervals of 1 °C. The scanning speed was 50 nm/min and a data pitch of 0.5 nm. A bandwidth of 2.5 nm was used with a sensitivity setting of medium. 4 ate scans were performed for each sample. The result suggest that both delta AB H66 and the T299A/Y3008 H66 mutant show similar thermal behavior and have the same onset temperature for degradation around 630. In other word, the mutant is as stable as the delta AB format.

See Figure 18.

Example 6 Functional is of Fc—engineered mutants PBMC proliferation and cytokine release assays were conducted as set forth in Example 2. Normal donor PBMC were thawed and treated under the following conditions (all in media containing complement): U] - Untreated - , molgG2b10ug/ml - OKT3, molgG2a10ug/ml 0 H66, hulgG1 deltaAB10ug/ml, 1ug/ml and 0.1ug/ml T299A/ Y3008 c H66, hulgG1 S298N/ 10ug/ml, 1ug/ml and 0.1ug/ml Cytokines were ted at day 2 (D2) and day 4 (D4) for Bioplex Analysis (IL2, lL4, IL6, lL8, lLlO, GM-CSF, IFNg, TNFa). Cells were stained at D4 for CD4, CD8, CD25 and abTCR expression.

The results, shown in Figures 19-22, demonstrate that H66 8298N/T299A/Y3008 behaved similarly to the H66 deltaAB in all cell based , showing minimal T-cell activation by CD25 expression; binding to abTCR, gh with slightly different kinetics to deltaAB; minimal cytokine release at both D2 and D4 time points; the mutant was in fact superior to deltaAB at D4 in respect of several of the cytokines.

The 8298N/T299A/Y3008 mutant thus eliminated effector function as effectively as the deltaAB mutation.

Example 7 Bispecific antibodies Bi—specific molecules were constructed comprised of two single chain antibodies (scFv) linked together via a short amino acid linker whereby one arm is capable of binding a tumor target and the other e of binding T cells via the 06 TCR. The ific le is referred to herein as a TRACER (T cell Receptor Activated Cytotoxic EnableR).

The following humanized anti—dBTCR scFv constructs were made: GL1BMASXVK1 GL1BMASXVK27 GL1BMASVH11XVK1 GL1BMASVH15XVK1 U] SVH28XVK43 GL1BMASVH31XVK43 The sequences of the heavy and light chains are set forth in SEQ ID nos 14-16 and 20-24 Characterization of these molecules comprised an assessment of binding to tumor target and T cells, in vitro cytotoxic activity and cytokine release profile in the presence and absence of tumor target cells.

The binding profile assessed by flow cytometery shows that anti— dB TCR bi—specific dies are able to bind both the tumor target cell line and T cells. See Figure 23.

I n v/fro cytotoxic activity measured by flow cytometery shows that T cells recruited via anti— dB TCR cific antibody are capable of inducing T cell mediated lysis. See Figure 24 Analysis of the cytokine release profile has shown that u binding of both arms of the cific antibody there is a high level of TH1/ cytokine release from the T cells which is not seen in the absence of target cells. Taken together this mechanism of action shows a similar profile to that of the CD3 based bispecifics described in the literature.

Example 8: Preparation and terization of an engineered Fc variant in anti- CD52 antibody.

In order to test the generality of the applicability of the Fc mutations described herein, glycosylation mutant 8298N/Y3008 was also prepared in an anti-CD52 antibody (clone 203) to see whether the or function modulation with the loss of chRlll binding applies to a different antibody backbone. S298N/Y3OOS 203 t DNA was prepared by quick change mutagenesis. The protein was purified from conditioned media after HEK293 ent ection. Anti—CD52 203 wild—type antibody was produced in parallel as a control. Biacore was used to characterize the antigen—binding, Fclell, and binding properties of the purified antibodies (see Figure 26).

Y3008 The S298N/ 203 variant binds to CD52 peptide tightly and the binding sensorgram is undistinguishable with the wild—type control, suggesting that this on on the Fc U‘i domain does not affect its antigen binding (Figure 26A).

To assay Fc or function, Fclell receptor (Val158) was used in binding studies. The mutant and wild-type control antibody were d to 200nM and injected to HPC4-tag ed Fclella. Fclell binding is almost undetectable for the S298N/Y3008 mutant, which indicates loss of effector function with this variant (Figure 268). The mutant also binds to FcRn receptor with the same affinity as the wild-type antibody control so we expect no change in its circulation half-life or other pharmacokinetic properties. (see YBOOS Figure 260). We conclude that the S298N/ mutation is able to antibodies in general, to reduce or eliminate undesired Fc effector function, for e through engagement of human Fcy receptors.

Claims (12)

Claims

1. A humanized onal antibody specific for the human ocBTCR/CDB complex which comprises a heavy chain variable region comprising an amino acid sequence selected from the group ting of the sequences set forth as SEQ ID NOs: 7, 12, 13, 15 and 16, and a light chain variable region comprising the amino acid sequence set forth as SEQ ID NO: 1

2. The humanized monoclonal antibody according to claim 1, wherein the heavy Chain variable region is ed from the group consisting of the amino acid ces set forth as SEQ ID NO: 7, SEQ ID NO: 12 and SEQ ID NO: 13.

3. The humanized monoclonal antibody according to claim 1, wherein the heavy chain variable region is selected from the group consisting of the amino acid sequences set forth as SEQ ID NO: 15 and SEQ ID NO: 16.

4. The humanized monoclonal antibody according to any one of the preceding claims, further comprising a constant region of human origin.

5. The humanized monoclonal antibody according to claim 4, further comprising an F0 modification which reduces Fcy receptor binding.

6. The humanized monoclonal antibody according to claim 5, which comprises an aglycosylayted Fc region or a delta ab modification.

7. The zed monoclonal dy according to claim 5, which comprises a modified glycosylation pattern.

8. A nucleic acid encoding at least a heavy chain variable region and a light chain variable region of a humanized monoclonal antibody ing to any one of claims 1 to 7.

9. An isolated cell which expressesethe nucleic acid according to claim 8, wherein cells capable of generating humans and transformed cells in a human host, are excluded.

10. A zed antibody according to any one of claims 1 to 7 for use in suppressing a T cell mediated response in a subject.

11. Use of a humanized antibody ing to any one of claims 1 to 7 in the cture of a medicament for use in suppressing a T cell mediated response in a subject.

12. A humanized dy according to claim 10 or the use according to claim 11, wherein the T ponse cell mediated res is involved in a condition selected from tissue transplantation including solid organ transplant and composite tissue transplant, tissue grafting, multiple sis and type 1 diabetes. GENZYME CORPORATION A T ER M A RK P A T E N T A N D T R A D E W MARKS ATTORNEYS P38649NZOO :03: gmo_>_ 5:: 6:80 _m_ Fmo<_>_m_ m>_03m