BINDING OF SOLUBLE NATURAL LIGANDS TO A SOLUBLE HUMAN T-CELL RECEPTOR FRAGMENT PRODUCED IN ESCHERICHIA-COLI

An Escherichia coli expression system has been developed to produce milligram quantities- of the variable domains of a human T-cell receptor from a cytotoxic T cell that recognizes the HLA-A2-influenza matrix peptide complex as a single polypeptide chain. The recombinant protein was purified by metal-chelate chromatography and then refolded in a redox buffer system. The refolded protein was shown to directly bind both Staphylococcus aureus enterotoxin B and the major histo compatibility complex protein-peptide complex using a BIAcore biosensor. Thus this preparation of a single-chain, variable-domain, T cell receptor fragment can bind both of its natural ligands and some of it is therefore a functional fragment of the receptor molecule.