The current invention provides methods to identify ³9´2T-cell receptor (³9´2TCR) that mediate anti-tumour responses. Suprisingly it was now found that the CDR3 regions of the ³9-T-cell receptor chain and the ´2-T-cell receptor chain (´2TCR chain) are of importance. Based on this findings, combinatorial- ³´TCR-chain-exchange (CTE) is proposed as an efficient method for identifying ³9´2TCR that mediate anti-tumour responses. Using the method of the invention, specific sequences of the respective y9TCR and ´2TCR chains were identified that mediate anti-tumour responses. Hence, the invention further provides for specific ³9´2TCRs, or fragments thereof, that may be used e.g. in diagnostics or treatment of cancer. The invention further provides for nucleic acid sequences, genetic constructs and retroviral vectors that can be used to express the ³9´2TCRs according to the invention.
