The present invention relates to a recombinant soluble T cell receptor. The T cell receptor (TCR) is refolded and comprises a recombinant TCR alpha or gamma chain extracellular domain having a first heterologous C-terminal dimerisation peptide; and a recombinant TCR beta or delta chain extracellular domain having a second C-terminal dimerisation peptide which is specifically heterodimerised with the first dimerisation peptide to form a heterodimerisation domain, which may be a coiled coil domain. The invention also provides nucleic acid sequences encoding the recombinant TCR and a method for producing the recombinant TCR. The TCR may be labelled with a detectable label so as to enable the detection of specific MHC-peptide complexes. Alternatively, it can be linked to a therapeutic agent such as a cytotoxic agent or an immunostimulating agent so as to deliver such an agent to the site of a specific MHC-peptide complex.
