KR20000070542A - Peptides Comprising a T-Cell Epitope Specific to Collagen II - Google Patents

Abstract

The present invention provides an isolated peptide having the amino acid sequence of the formula (I) and its use in medical treatment, in particular in the treatment of autoimmune diseases such as rheumatoid arthritis.

<Formula I>

A ₁ -Xaa-Gly-A ₄ -A ₅ -Gly-A ₇ -Xaa-Gly

In the above formula, A ₁ represents an amino acid residue with an aromatic or aliphatic side chain,

A ₄ represents an asparagine or arginine residue or an amino acid residue having an aromatic or aliphatic side chain,

A ₅ can be any natural amino acid,

A ₇ represents an amino acid with a negatively charged residue,

Xaa can be any amino acid,

Gly represents a glycine residue.

Description

Peptides Comprising a T-Cell Epitope Specific to Collagen II

The present invention provides novel peptides derived from type II collagen (CII), methods for their preparation and their use in medical treatment, in particular in the treatment of rheumatoid arthritis and related autoimmune diseases.

Collagen molecules are some of the major structural proteins of connective tissue. The collagen molecule consists of three polypeptide chains, which form an elongated three-stranded helix with a unique X-Y-Gly repeating amino acid sequence. The extracellular matrix of cartilage is unique in that it mainly contains type II collagen, but there are also type IX and XI collagen. CII has recently been cloned from mice and its total amino acid sequence 1419 has been determined (Metsarantam et al., 1991, J. Biol. Chem., 266: 16862-9)

Collagen type II is believed to be inaccessible to cells of the immune system because it is found only in non-vascular tissues such as cartilage and eye vitreous. Thus, the immune system is not completely tolerant of its type II collagen. CII, an isolated protein, can be dissolved and injected into Freund's complete adjuvant to cause tissue specific autoimmune diseases. The disease caused by collagen is called collagen-induced arthritis (CIA). Collagen-induced arthritis (CIA) is usually caused by the injection of foreign CII, caused by the foreign CII production of T cells and antibodies capable of recognizing its own protein corresponding to the foreign CII.

Susceptibility to collagen induced arthritis (CIA) in mice is limited to MHC types IA ^q and IA ^r . The binding motifs of these molecules are similar to the binding motifs of human DR4 and DR1. CII is therefore believed to be an autoantigen of rheumatoid arthritis (RA).

There is currently no possible cure for rheumatoid arthritis. Existing therapies, such as adding corticosteroids, are nonspecific because they suppress the entire immune system. Recent studies suggest that autoreactive T cells play an important role in the development of rheumatoid arthritis. This fact leads to the idea that tolerating these pathogenic T cells by intranasal / oral administration of immunogenic peptides may have therapeutic potential.

Miyahara H. et al., Immunology, 1995, 86, 110-115 describe the use of type II collagen fragments in the inhibition of arthritis in mice. However, since the fragment used (CII 602-621) does not contain a binding motif for any of the HLA-DR molecules involved in human rheumatoid arthritis, it is an immunotolerant in the treatment of human rheumatoid arthritis. It will not be effective to use.

WO 96/20950 describes that type II collagen peptides capable of binding human HLA DRB1 MHC proteins may be used to treat rheumatoid arthritis. However, these peptides present at the 273-404 site of collagen type II (CII) protein show only weak activity in the relevant assays of the predicted immunotolerant for rheumatoid arthritis. In comparison, the peptides of the present invention have significant therapeutic efficacy.

The present invention provides peptides found to be particularly effective in inducing immune tolerance against type II collagen (CII) derived T cell epitopes. These peptides can be used for the treatment of autoimmune diseases such as rheumatoid arthritis.

According to the present invention there is provided an isolated peptide having or comprising the amino acid sequence of the formula (I).

A ₁ -Xaa-Gly-A ₄ -A ₅ -Gly-A ₇ -Xaa-Gly

In the above formula, A ₁ represents an amino acid residue with an aromatic or aliphatic side chain,

A ₄ represents an asparagine or arginine residue or an amino acid residue having an aromatic or aliphatic side chain,

A ₅ can be any natural amino acid,

A ₇ represents an amino acid with a negatively charged residue,

Xaa can be any amino acid,

Gly represents a glycine residue.

The peptide of the present invention is preferably 9, 10, 11, 12, 13, 14 or 15 amino acid peptides, more preferably 9 amino acid peptides.

In the peptide of the present invention, the following independent preferences are applied.

-A ₁ is any _one of Phe (F), Ile (I), Leu (L), Ala (A), Pro (P), most preferably Phe (F).

-A ₄ is any one of Phe (F), Ile (I), Leu (L), Ala (A), Arg (R), Asn (N), Pro (P), most preferably Phe (F) )to be.

-A ₅ is Lys (K) or Arg (R).

-A ₇ is any one of Glu (E), Asp (D), Gln (Q), Pro (P), Asn (N), most preferably Gln (Q).

Preferred peptides according to the invention include the following amino acid sequences 1-25

SEQ ID NO: 1 Glu Ser Gly Ser Pro Gly Glu Asn Gly

SEQ ID NO: 2: Pro Pro Gly Ala Asp Gly Gln Pro Gly

SEQ ID NO: 3 Ala Arg Gly Asn Asp Gly Gln Pro Gly

SEQ ID NO: 4 Gln Pro Gly Ala Lys Gly Asp Gln Gly

SEQ ID NO 5: Ala Pro Gly Ala Lys Gly Glu Ala Gly

SEQ ID NO: 6: Pro Thr Gly Val Thr Gly Pro Lys Gly

SEQ ID NO: 7: Ala Gln Gly Ser Arg Gly Glu Pro Gly

SEQ ID NO: 8: Arg Val Gly Pro Pro Gly Ala Asn Gly

SEQ ID NO: 9: Pro Ala Gly Ala Ser Gly Asn Pro Gly

SEQ ID NO: 10: Ala Asn Gly Asn Pro Gly Pro Ala Gly

SEQ ID NO: 11: Thr Asp Gly Ile Pro Gly Ala Lys Gly

SEQ ID NO: 12 Asp Pro Gly Leu Gln Gly Pro Ala Gly

SEQ ID NO: 13: Ser Ala Gly Ala Pro Gly Ile Ala Gly

SEQ ID NO: 14 Ala Pro Gly Glu Lys Gly Glu Pro Gly

SEQ ID NO: 15 Ile Ala Gly Ala Pro Gly Phe Pro Gly

SEQ ID NO: 16: Pro Gln Gly Leu Ala Gly Gln Arg Gly

SEQ ID NO: 17 Phe Pro Gly Pro Arg Gly Pro Pro Gly

SEQ ID NO: 18 Pro Pro Lys Gly Ala Asn Gly Asp Pro Gly

SEQ ID NO: 19: Ala Pro Gly Ala Ser Gly Asp Arg Gly

SEQ ID NO: 20 Leu Pro Gly Ala Arg Gly Leu Thr Gly

SEQ ID NO: 21 Asp Ala Gly Pro Gln Gly Lys Val Gly

SEQ ID NO: 22 Ala Leu Gly Ala Pro Gly Ala Pro Gly

SEQ ID NO: 23 Pro Ala Gly Ala Asn Gly Glu Lys Gly

SEQ ID NO: 24 Lys Gln Gly Asp Arg Gly Glu Ala Gly

SEQ ID NO: 25 Ala Arg Gly Ala Pro Gly Glu Pro Gly

And those containing or having any of them, more preferred are Arg Val Gly Pro Pro Gly Ala Asn Gly (SEQ ID NO: 8) or Ala Asn Gly Asn Pro Gly Pro Ala Gly (SEQ ID NO: 10).

In addition, preferred examples of the peptide according to the present invention include the following amino acid sequences 26-52

SEQ ID NO 26: Val Lys Gly Glu Ser Gly Ser Pro Gly Glu Asn Gly Ser Pro Gly

SEQ ID NO: 27 Phe Ala Gly Pro Pro Gly Ala Asp Gly Gln Pro Gly Ala Lys Gly

SEQ ID NO: 28 Ala Ala Gly Ala Arg Gly Asn Asp Gly Gln Pro Gly Pro Ala Gly

SEQ ID NO: 29 Ala Asp Gly Gln Pro Gly Ala Lys Gly Asp Gln Gly Glu Ala Gly

SEQ ID NO: 30 Ala Pro Gly Ala Lys Gly Glu Ala Gly Pro Thr Gly Ala Arg Gly

SEQ ID NO: 31 Pro Gln Gly Pro Thr Gly Val Thr Gly Pro Lys Gly Ala Arg Gly

SEQ ID NO: 32 Pro Glu Gly Ala Gln Gly Ser Arg Gly Glu Pro Gly Asn Pro Gly

SEQ ID NO: 33 Ala Ala Gly Arg Val Gly Pro Pro Gly Ala Asn Gly Asn Pro Gly

SEQ ID NO: 34 Pro Ala Gly Ala Ser Gly Asn Pro Gly Thr Asp Gly Ile Pro Gly

SEQ ID NO: 35 Pro Pro Gly Ala Asn Gly Asn Pro Gly Pro Ala Gly Pro Pro Gly

SEQ ID NO: 36 Asn Pro Gly Thr Asp Gly Ile Pro Gly Ala Lys Gly Ser Ala Gly

SEQ ID NO: 37 Arg Ala Gly Asp Pro Gly Leu Gln Gly Pro Ala Gly Ala Pro Gly

SEQ ID NO: 38 Ala Lys Gly Ser Ala Gly Ala Pro Gly Ile Ala Gly Ala Pro Gly

SEQ ID NO: 39 Pro Ala Gly Ala Pro Gly Glu Lys Gly Glu Pro Gly Asp Asp Gly

SEQ ID NO: 40 Ala Pro Gly Ile Ala Gly Ala Pro Gly Phe Pro Gly Pro Arg Gly

SEQ ID NO: 41 Pro Pro Gly Pro Gln Gly Leu Ala Gly Gln Arg Gly Ile Val Gly

SEQ ID NO: 42 Ala Pro Gly Phe Pro Gly Pro Arg Gly Pro Pro Gly Pro Gln Gly

SEQ ID NO: 43 Leu Ala Gly Pro Lys Gly Ala Asn Gly Asp Pro Gly Arg Pro Gly

SEQ ID NO: 44 Lys Gln Gly Ala Pro Gly Ala Ser Gly Asp Arg Gly Pro Pro Gly

SEQ ID NO: 45 Glu Pro Gly Leu Pro Gly Ala Arg Gly Leu Thr Gly Arg Pro Gly

SEQ ID NO: 46 Arg Pro Gly Asp Ala Gly Pro Gln Gly Lys Val Gly Pro Ser Gly

SEQ ID NO: 47 Glu Thr Gly Ala Leu Gly Ala Pro Gly Ala Pro Gly Pro Pro Gly

SEQ ID NO: 48 Pro Pro Gly Pro Ala Gly Ala Asn Gly Glu Lys Gly Glu Val Gly

SEQ ID NO: 49 Pro Thr Gly Lys Gln Gly Asp Arg Gly Glu Ala Gly Ala Gln Gly

SEQ ID NO: 50 Ser Ser Gly Ala Arg Gly Ala Pro Gly Glu Pro Gly Glu Thr Gly

SEQ ID NO: 51 Ala Ala Gly Arg Val Gly Pro Pro Gly Ala Asn Gly Asn Pro Gly

SEQ ID NO: 52: Pro Pro Gly Ala Asn Gly Asn Pro Gly Pro Ala Gly Pro Pro Gly

And those which include or have any one of them, more preferably Ala Ala Gly Arg Val Gly Pro Pro Gly Ala Asn Gly Asn Pro Gly (SEQ ID NO: 2) or Pro Pro Gly Ala Asn Pro Gly Pro Ala Gly Pro Pro Gly (SEQ ID NO: 35 )to be.

Preferably the peptide according to the invention comprises a contiguous 9-15 amino acid sequence of the 701-721 region of type II collagen.

The invention also provides a peptide comprising at least 9 amino acids having the same sequence as that sequence, selected sequentially from the 110-239, 338-379, 587-895 site sequences of type II collagen, wherein each amino acid is a functional equivalent amino acid. A peptide comprising a T cell epitope specific for type II collagen, a peptide of formula I as defined above, is optionally substituted with.

According to the present invention there is also provided a pharmaceutical composition containing a peptide according to the invention together with a pharmaceutically acceptable carrier or diluent. This composition is preferably used to provide immune tolerance to autoimmune diseases such as rheumatoid arthritis and recurrent polychondritis.

The invention also provides the use of a peptide according to the invention and a composition according to the invention in the manufacture of a medicament for the treatment of autoimmune diseases.

According to the present invention, there is also provided a method for treating a person or animal suffering from an autoimmune disease such as rheumatoid arthritis and recurrent polychondritis, which method provides a therapeutically effective amount of a peptide or composition of the present invention. (Comprise).

Peptides according to the invention can be prepared using methods known to those skilled in the art. For example, automated polypeptide synthesizers can be prepared via standard solid-phase continuous coupling techniques (eg Jones, J. The Chemical Synthesis of Peptides, pp 132-156, 1st Ed., Oxford University Press, 1991 and R. Epton (ed) Innovation and Perspectives in Solid Phase Peptide Synthesis, SPCC (UK), Ltd., 1990). The preparation starts at C-terminal amino acids, which can be obtained by grafting on methylbenzhydrylamine, benzhydrylamine or chloromethylated resin or on a suitable solid support. The other amino acid is first grafted stepwise after its side chain is protected. In this coupling method the alpha amino group of an amino acid is protected by the F-moc or t-Boc method. Protecting groups for the side chains of amino acids are well known in the art. In the case of the chloromethylated resin, the whole protected peptide is separated by ammonia hydrolysis to obtain a protected amide, and in the case of methylbenzhydrylamine or benzhydrylamine resin, the entire protected peptide is dropped through acid hydrolysis.

Peptides according to the invention can also be prepared using a solution method via either stepwise condensation or fragment condensation (eg Jones, J. The Chemical Synthesis of Peptides, pp. 115-131, 1st Ed., Oxford). See Unversity Press, 1991). Suitably the α-aminoprotected amino acid is coupled to the appropriate α-carboxylprotected amino acid using diimides, symmetric or asymmetric anhydrides, or other coupling agents or techniques known to those skilled in the art, where the protection is the selected coupling method. May not be necessary). This technique can be either chemical or enzymatic. The peptide is extended longer and longer by removing the α-amino acid and / or α-carboxyl protecting group and coupling the next stable protected amino acid or block of amino acids. Various combinations of protecting groups and various combinations of chemical and / or enzymatic and assembly methods can be used for each synthesis.

Peptides according to the invention are defined as comprising T cell epitopes. In other words, the peptide of the present invention can activate T cells. Several techniques for measuring bond strength are known. Peptides according to the invention have a binding strength of at least 2 in the IFN-γ release assay and can activate T cells with a stimulation index of at least 3. IFN- [gamma] release assays can be performed using the methods described in the Examples herein or using methods known in the art. Similarly, the stimulation index can be determined using known proliferation assays such as those described in "Analysis of type II collagen reactive T cells in the mouse" Andersson and Holmdahl, Eur. J. Immunol. 20: 1061-1066, 1990). Can be determined and this analysis is preferably performed by the method used in the Examples herein.

The peptide of the present invention is used for treatment without modification, but may also be modified by covalent bonding or the like, for example, to a delivery system such as a mucosal binding structure including cholera β toxin, which aids absorption in the small intestine.

The peptides of the present invention can be used for the treatment, prevention or diagnosis of autoimmune diseases, and the terms "therapeutic" and "treatment" as used herein should be understood to encompass prevention and diagnosis.

It is to be understood that the peptides of the present invention are isolated peptides in the sense that they do not include peptides present in the organism. Peptides of the invention can be isolated from naturally occurring or recombinantly produced peptides or proteins or can be chemically synthesized as described above.

The compounds of the present invention may be administered in a single dose of about 10 μg to 10 mg per day or divided into two to four times a day. Thus, the unit dose contains 2.5 μg to 10 mg of the compound according to the invention. The compound may be administered intranasally in the form of solutions, suspensions, HFA aerosols, dry powders, for example the trademark Turbuhaler formulations or systemic administration, for example in the form of tablets, pills, capsules, syrups, powders or granules. It can be administered orally, or parenterally in the form of sterile parenteral solutions or suspensions or rectally in the form of suppositories.

The compounds of the invention may be administered on their own or as pharmaceutical compositions containing a compound of the invention in combination with a pharmaceutically acceptable diluent, adjuvant or carrier. Especially preferred are compositions that are free of substances that can cause side effects such as allergic reactions.

Dry powders and pressurized HFA aerosols of the compounds of this invention may be administered by nasal inhalation. For inhalation, the finely divided compound is preferred. The finely divided compound preferably has a mass median diameter of less than 10 μm, C ₈ -C ₂₀ fatty acids or salts thereof (for example oleic acid), bile salts, phospholipids, alkyl saccharides, perfluorinated or polyethoxy It may be suspended in a propellant mixture which auxiliaryly contains a dispersing agent such as a flame retardant or other pharmaceutically acceptable dispersing agent.

The compounds of the present invention can also be administered using a dry powder inhaler. This inhaler may be a single dose or multidose inhaler and may be a breath operated dry powder inhaler.

The finely divided compound may be mixed with a carrier material such as monosaccharides, disaccharides, polysaccharides, sugar alcohols or other polyhydric alcohols. Suitable carriers are sugars such as lactose, glucose, raffinose, melezitose, lactitol, maltitol, trehalose, sucrose, mannitol and starch. The fine compound can also be coated with other materials. Powder mixtures may also be formulated into hard gelatin capsules, each containing the desired active compound dose.

Pharmaceutical compositions containing a compound of the present invention may typically be tablets, pills, capsules, syrups, powders or granules for oral administration, sterile parenteral solutions or suspensions for parenteral administration, or suppositories for rectal administration. .

For oral administration, the active compound may be added as an adjuvant or carrier, such as lactose, saccharose, sorbitol, mannitol, starch (e.g. potato starch, corn starch, amylopectin), cellulose derivatives, binders (e.g. gelatin or polyvinylpi Ralidone) and a lubricant (eg, magnesium stearate, calcium stearate, polyethylene glycol, wax, paraffin, etc.) and then compressed into tablets. If epidermal tablets are required, the cores prepared as described above may be coated with a sugar concentrate which may contain gum arabic, gelatin, talc, titanium dioxide and the like. Tablets may also be coated with an easily volatile organic solvent in which the appropriate polymer is dissolved.

To prepare soft gelatin capsules, the compounds can be mixed with vegetable oils or polyethylene glycols and the like. Hard gelatin capsules may comprise granules of the compound using any of the aforementioned excipients for tablets, for example, lactose, saccharose, sorbitol, mannitol, starch, cellulose derivatives or gelatin. It is also possible to fill hard gelatin capsules with liquid or semisolid formulations of medicine.

Liquid preparations for oral administration may be in the form of syrups or suspensions, for example in the form of solutions containing the compounds of the invention and the remainder of which are sugars and mixtures of ethanol, water, glycerol and propylene glycol. . In some cases such liquid preparations may contain colorants, flavors, thickeners saccharin and carboxymethylcellulose or other excipients known to those skilled in the art.

The invention will now be illustrated by the following examples, which should not be construed as limiting the invention.

<Example 1>

The CII peptide chains listed in Table 1 consisted of 15 amino acids each, and were synthesized by known Fmoc chemistry using an SMPS 350 automated synthesizer (Zinsser, Frankfurt / Main, Germany) (Atherton and Sheppard, Solid Phase). Peptide Synthesis-A Practical Approach, IRL Press, Oxford. Each peptide was then acetylated at the N terminus and amidated at the C terminus. The amount of peptide was measured by HPLC, and the peptide sample confirmed the expected molecular weight by mass spectrometry.

The amino acids shown in bold have been found to be the most strongly bound amino acid portions when comparing the binding strengths of the core sequences, structurally adjacent peptides.

<Example 2>

Mice CII were extracted by digestion with pepsin using known techniques in the dendritic spines and further purified by salt precipitation. Rat CII was again purified from Swarm cartilage sarcoma using known techniques. These collagen were dissolved in 0.1 M acetic acid. Collagen for use in restimulating primed lymph node cells was denatured by incubation at 56 ° C. for 30 minutes.

<Example 3>

To test for proliferative response and cytokine release in drained lymph node cells, CFA (H37Ra, Difco, USA) of 7-10 week old male (B10.Q x DBA / 1) F1 mice was found in the hind paw. Inoculated with 50 μg mouse CII or synthetic peptides emulsified in Detroit, Michigan. 100 μg of rat CII emulsified CFA prepared in Example 2 was inoculated at the base of the mouse tail to induce arthritis in the same mice at 7-10 weeks of age.

Five weeks later, mice were inoculated with 50 μg of CII emulsified with IFA (Difco, Detroit, Mich.) At a weight ratio of 1: 1. The lymph node cells drained from the joints of these mice with severe arthritis were then collected and tested for reactivity to the mouse CII peptide plates prepared in Example 1 in the proliferation assay in the following manner.

Cytokine release was performed using mouse IFN-γ and IL-4 minikits (Endogen, Cambridge, Mass.) And re-stimulated in vitro using a CII peptide plate prepared according to Example 1 50 μl of primary culture supernatant was analyzed.

<Example 4>

Lymph node cells obtained from mice first stimulated with mouse CII were either monoclonal rat anti-mouse L3T4 (CD4) antibody or rat anti-mouse B220 (CD45R) (both from Miltenyi Biotec GmbH, Bergisch Gladbach, Germany). Was passed through a magnetically activated cell sorter (MACS) using superparamagnetic microglass pellets conjugated as directed, containing 2% FCS, 5 mM EDTA, 50 μM 2-ME and 10 mM HEPES instead of PBS / BSA buffer. T cells or B cells were removed using PBS. FITScan-conjugated anti-mouse-CD3-ε for T cell staining and FITC-conjugated anti-mouse-κ-light chain for B cell staining (Pharmigen, San Francisco, CA, USA) FACScan flow cytometer ( Fractions were analyzed by Becton Dickinson). After separation, cells were washed three times with serum-free DMEM medium and then subjected to a proliferation assay performed by the method described in Example 3. Enhanced CD4 + T cells were mixed with splenic cells (antigen presenting cells) obtained in syngeneic mice at a weight ratio of 1: 2. AP cells (antigen presenting cells) are used in the form of single cell suspensions obtained from spleens lysed with red blood cells treated with 0.84% NH4Cl (pH 7.4).

Cell morphology CPM x 10 ^-3 Nonfragmentation 13.6 CD4 + Enhancement 21.4 CD4 + depletion 0.3 CD45R + depletion 12.5 CD45R + Reinforcement 0.4

Claims (19)

Isolated peptide having the amino acid sequence of formula (I) <Formula I> A ₁ -Xaa-Gly-A ₄ -A ₅ -Gly-A ₇ -Xaa-Gly In the above formula, A ₁ represents an amino acid residue with an aromatic or aliphatic side chain, A ₄ represents an asparagine or arginine residue or an amino acid residue having an aromatic or aliphatic side chain, A ₅ represents any natural amino acid, A ₇ represents an amino acid with a negatively charged residue, Xaa represents any amino acid, Gly represents a glycine residue. An isolated peptide comprising the amino acid sequence of any of the peptides of claim 1. The peptide of claim 2 comprising 10 to 15 amino acids. The peptide of claim 1, wherein A ₅ is a lysine or arginine residue and A ₇ is a glutamic acid residue. An isolated peptide having any one of the following SEQ ID NOs: 1-25. SEQ ID NO: 1 Glu Ser Gly Ser Pro Gly Glu Asn Gly SEQ ID NO: 2: Pro Pro Gly Ala Asp Gly Gln Pro Gly SEQ ID NO: 3 Ala Arg Gly Asn Asp Gly Gln Pro Gly SEQ ID NO: 4 Gln Pro Gly Ala Lys Gly Asp Gln Gly SEQ ID NO 5: Ala Pro Gly Ala Lys Gly Glu Ala Gly SEQ ID NO: 6: Pro Thr Gly Val Thr Gly Pro Lys Gly SEQ ID NO: 7: Ala Gln Gly Ser Arg Gly Glu Pro Gly SEQ ID NO: 8: Arg Val Gly Pro Pro Gly Ala Asn Gly SEQ ID NO: 9: Pro Ala Gly Ala Ser Gly Asn Pro Gly SEQ ID NO: 10: Ala Asn Gly Asn Pro Gly Pro Ala Gly SEQ ID NO: 11: Thr Asp Gly Ile Pro Gly Ala Lys Gly SEQ ID NO: 12 Asp Pro Gly Leu Gln Gly Pro Ala Gly SEQ ID NO: 13: Ser Ala Gly Ala Pro Gly Ile Ala Gly SEQ ID NO: 14 Ala Pro Gly Glu Lys Gly Glu Pro Gly SEQ ID NO: 15 Ile Ala Gly Ala Pro Gly Phe Pro Gly SEQ ID NO: 16: Pro Gln Gly Leu Ala Gly Gln Arg Gly SEQ ID NO: 17 Phe Pro Gly Pro Arg Gly Pro Pro Gly SEQ ID NO: 18 Pro Pro Lys Gly Ala Asn Gly Asp Pro Gly SEQ ID NO: 19: Ala Pro Gly Ala Ser Gly Asp Arg Gly SEQ ID NO: 20 Leu Pro Gly Ala Arg Gly Leu Thr Gly SEQ ID NO: 21 Asp Ala Gly Pro Gln Gly Lys Val Gly SEQ ID NO: 22 Ala Leu Gly Ala Pro Gly Ala Pro Gly SEQ ID NO: 23 Pro Ala Gly Ala Asn Gly Glu Lys Gly SEQ ID NO: 24 Lys Gln Gly Asp Arg Gly Glu Ala Gly SEQ ID NO: 25 Ala Arg Gly Ala Pro Gly Glu Pro Gly An isolated peptide comprising the amino acid sequence of any of the peptides of claim 3. An isolated peptide having any one of the following amino acid sequences 26-52. SEQ ID NO 26: Val Lys Gly Glu Ser Gly Ser Pro Gly Glu Asn Gly Ser Pro Gly SEQ ID NO: 27 Phe Ala Gly Pro Pro Gly Ala Asp Gly Gln Pro Gly Ala Lys Gly SEQ ID NO: 28 Ala Ala Gly Ala Arg Gly Asn Asp Gly Gln Pro Gly Pro Ala Gly SEQ ID NO: 29 Ala Asp Gly Gln Pro Gly Ala Lys Gly Asp Gln Gly Glu Ala Gly SEQ ID NO: 30 Ala Pro Gly Ala Lys Gly Glu Ala Gly Pro Thr Gly Ala Arg Gly SEQ ID NO: 31 Pro Gln Gly Pro Thr Gly Val Thr Gly Pro Lys Gly Ala Arg Gly SEQ ID NO: 32 Pro Glu Gly Ala Gln Gly Ser Arg Gly Glu Pro Gly Asn Pro Gly SEQ ID NO: 33 Ala Ala Gly Arg Val Gly Pro Pro Gly Ala Asn Gly Asn Pro Gly SEQ ID NO: 34 Pro Ala Gly Ala Ser Gly Asn Pro Gly Thr Asp Gly Ile Pro Gly SEQ ID NO: 35 Pro Pro Gly Ala Asn Gly Asn Pro Gly Pro Ala Gly Pro Pro Gly SEQ ID NO: 36 Asn Pro Gly Thr Asp Gly Ile Pro Gly Ala Lys Gly Ser Ala Gly SEQ ID NO: 37 Arg Ala Gly Asp Pro Gly Leu Gln Gly Pro Ala Gly Ala Pro Gly SEQ ID NO: 38 Ala Lys Gly Ser Ala Gly Ala Pro Gly Ile Ala Gly Ala Pro Gly SEQ ID NO: 39 Pro Ala Gly Ala Pro Gly Glu Lys Gly Glu Pro Gly Asp Asp Gly SEQ ID NO: 40 Ala Pro Gly Ile Ala Gly Ala Pro Gly Phe Pro Gly Pro Arg Gly SEQ ID NO: 41 Pro Pro Gly Pro Gln Gly Leu Ala Gly Gln Arg Gly Ile Val Gly SEQ ID NO: 42 Ala Pro Gly Phe Pro Gly Pro Arg Gly Pro Pro Gly Pro Gln Gly SEQ ID NO: 43 Leu Ala Gly Pro Lys Gly Ala Asn Gly Asp Pro Gly Arg Pro Gly SEQ ID NO: 44 Lys Gln Gly Ala Pro Gly Ala Ser Gly Asp Arg Gly Pro Pro Gly SEQ ID NO: 45 Glu Pro Gly Leu Pro Gly Ala Arg Gly Leu Thr Gly Arg Pro Gly SEQ ID NO: 46 Arg Pro Gly Asp Ala Gly Pro Gln Gly Lys Val Gly Pro Ser Gly SEQ ID NO: 47 Glu Thr Gly Ala Leu Gly Ala Pro Gly Ala Pro Gly Pro Pro Gly SEQ ID NO: 48 Pro Pro Gly Pro Ala Gly Ala Asn Gly Glu Lys Gly Glu Val Gly SEQ ID NO: 49 Pro Thr Gly Lys Gln Gly Asp Arg Gly Glu Ala Gly Ala Gln Gly SEQ ID NO: 50 Ser Ser Gly Ala Arg Gly Ala Pro Gly Glu Pro Gly Glu Thr Gly SEQ ID NO: 51 Ala Ala Gly Arg Val Gly Pro Pro Gly Ala Asn Gly Asn Pro Gly SEQ ID NO: 52: Pro Pro Gly Ala Asn Gly Asn Pro Gly Pro Ala Gly Pro Pro Gly An isolated peptide which is a 10-14 amino acid fragment of any of the peptides described in claim 7. The peptide of any one of claims 1-8, which binds to T cells with a binding strength of at least two in an IFN-γ release assay. The peptide according to any one of claims 1 to 9, which binds to T cells with a stimulation index of 3 or higher. The peptide of any one of claims 1-10, wherein the sequence is at positions 110-239, 338-379 or 587-895 in the sequence of type II collagen. The peptide of claim 11, wherein the sequence is in the 701-721 region of type II collagen. Isolated peptide for medical treatment according to any one of claims 1 to 12. The peptide of claim 13, wherein said medical treatment comprises induction of immune tolerance. Use of the isolated peptide according to any one of claims 1 to 14 in the manufacture of a medicament for the treatment of autoimmune diseases. Use according to claim 10, wherein said autoimmune disease is rheumatoid arthritis. A pharmaceutical composition comprising a peptide according to claim 1 and a pharmaceutically acceptable carrier or diluent therefor. A method of treating a human or animal with or possibly suffering from an autoimmune disease comprising providing to the human or animal a therapeutically effective amount of the peptide according to any one of claims 1 to 12 or the composition according to claim 17. Wherein the sequences are identical to the 110-239, 338-379, and 587-895 sites of the type II collagen sequence and include nine or more amino acids selected sequentially at that site, wherein each amino acid may be replaced with a functional equivalent amino acid; A peptide comprising a T cell epitope specific for type II collagen, having a structure of Formula (I): <Formula I> A ₁ -Xaa-Gly-A ₄ -A ₅ -Gly-A ₇ -Xaa-Gly In the above formula, A ₁ represents an amino acid residue with an aromatic or aliphatic side chain, A ₄ represents an asparagine or arginine residue or an amino acid residue having an aromatic or aliphatic side chain, A ₅ represents any natural amino acid, A ₇ represents an amino acid with a negatively charged residue, Xaa represents any amino acid, Gly represents a glycine residue.