Loss of serological determinants does not affect recognition of H-2Kk target cells by an influenza-specific cytotoxic T cell clone.

The recognition of "self determinants" by an H-2Kk-restricted cytotoxic T (Tc) cell clone (K5) has been investigated as follows: (a) differential inhibition of cytotoxicity by several monoclonal antibodies directed to determinants on the H-2Kk molecule of the target cells and (b) recognition and lysis of target cell variants of cell line LDHB, which have lost the majority or all of the serological determinants defined by the inhibiting antibodies while still expressing an H-2Kk molecule. Such variant cells infected with influenza virus were effectively recognized by Tc cell clone K5, whereas a target cell line, which lacks the Kk molecule, was not lysed. The results suggest; (a) that virus-specific Tc cell see "self" in a manner distinct from the recognition of serological determinants by B cell and (b) that antibody inhibition indicates conformational closeness, but not identity, of the class I determinant seen by T cells.