Soluble class I MHC with β₂-microglobulin covalently linked peptides: Specific binding to a T cell hybridoma

Soluble forms of the mouse MHC class I molecule, D(d), were produced in which the peptide binding groove was uniformly occupied by peptides attached via a covalent flexible peptide linker to the N terminus of the associated β₂-microglobulin. The MHC heavy chain and β₂-microglobulin were firmly associated, and the molecules displayed an Ab epitope requiring proper occupancy of the peptide binding groove. Soluble D(d) containing a covalent version of a well-characterized D(d)-binding peptide from HIV stimulated a T cell hybridoma specific for this combination. Furthermore, a tetravalent version of this molecule bound specifically with apparent high avidity to this hybridoma.