TCR LIBRARIES

1 . A library of particles, the library displaying a plurality of different T cell receptors (TCRs), wherein the plurality of TCRs consists essentially of TCRs comprising an alpha chain comprising an alpha chain variable domain and a beta chain comprising a beta chain variable domain, wherein the alpha chain variable domain comprises a TRAV17 gene product and the beta chain variable domain comprises a TRBV2 gene product.

2 . The library according to claim 1 wherein the CDR3 sequence of the alpha and/or beta chain variable domains are obtained from a natural repertoire.

3 . The library of claim 1 , wherein the CDR3 sequence of the alpha and/or beta chain variable domains is designed artificially.

4 . The library of claim 1 , wherein the framework region, CDR1, CDR2 and/or CDR3 sequence of the alpha and/or beta variable domain comprises a non-natural mutation a non-natural mutation.

5 . The library of claim 1 , wherein the alpha chain variable domain and the beta chain variable domain are displayed as a single polypeptide chain.

6 . The library of claim 1 , wherein the TCRs comprise a non-native disulphide bond between a constant region of the alpha chain and a constant region of the beta chain.

7 . The library of claim 1 , wherein the TCRs comprise a native disulphide bond between a constant region of the alpha chain and a constant region of the beta chain.

8 . The library of claim 1 , wherein each alpha chain and each beta chain comprises a dimerization domain.

9 . The library according to claim 8 , wherein the dimerization domain is heterologous.

10 . The library of claim 1 , wherein the particles are phage particles.

11 . The library of claim 1 , wherein the particles are ribosomes.

12 . The library of claim 1 , wherein the particles are yeast cells.

13 . The library of claim 1 , wherein the particles are mammalian cells.

14 . A non-natural isolated T cell receptor (TCR) comprising a TCR alpha chain variable domain comprising a TRAV17 gene product and a TCR beta chain variable domain comprising a TRBV2 gene product obtained from the library of claim 1 .

15 . (canceled)

16 . (canceled)

17 . A method of obtaining a T cell receptor that specifically binds a peptide antigen, comprising screening the library of claim 1 with the peptide antigen, the method comprising:

a) panning the library using as a target the peptide antigen;

b) repeating step a) one or more times;

c) screening the phage clones identified in step a) or b); and

d) identifying a TCR that specifically binds the peptide antigen.

18 . A nucleic acid encoding a TCR alpha chain variable domain and/or a beta chain variable domain of the TCR of claim 14 .

19 . A method of making a library of particles, the library displaying a plurality of different TCRs, the method comprising:

i) obtaining a plurality of nucleic acids that encode different TRAV17 alpha chain variable domains;

ii) obtaining a plurality of nucleic acids that encode different TRBV2 beta chain variable domains;

iii) cloning the TRAV17 alpha chain variable domain encoding nucleic acids into expression vectors;

iv) cloning the TRBV2 beta chain variable domain encoding nucleic acids into the same or different vectors; and

v) expressing the vectors in particles, thereby generating a library consisting essentially of TCRs comprising an alpha chain variable domain and a beta chain variable domain encoded by the nucleic acids.

20 . A method of making a library of particles, the library displaying a plurality of different TCRs, the method comprising:

i) obtaining a plurality of nucleic acids that encode different TRAV17 alpha chain variable domains using primers that hybridise to nucleic acids encoding TRAV17 alpha chain variable domains;

ii) obtaining a plurality of nucleic acids that encode different TRBV2 beta chain variable domains using primers that hybridise to nucleic acids encoding TRBV2 beta chain variable domains;

iii) cloning the TRAV17 alpha chain variable domain encoding nucleic acids into expression vectors;

iv) cloning the TRBV2 beta chain variable domain encoding nucleic acids into the same or different vectors; and

v) expressing the vectors in particles, thereby generating a library consisting essentially of TCRs comprising an alpha chain variable domain and a beta chain variable domain encoded by the nucleic acids to which said primers hybridise.

21 .- 29 . (canceled)

30 . A particle displaying on its surface the TCR of claim 14 .

31 . (canceled)

32 . The method of claim 19 , wherein

the particles are phage particles; and

the primers that hybridize to nucleic acids encoding TRAV17 alpha chain variable domains consist of SEQ ID NOS: 2, 5, 7, and 8; and

the primers that hybridize to nucleic acids encoding TRBV2 beta chain variable domains consist of SEQ ID NOS: 1, 3, 6, and 9; and

the expression vectors are pIM672.

33 . A library of particles made by the method of claim 32 .