Molecular localization of allogeneic and self determinants recognized by bulk and clonal populations of cytotoxic T cells

The localization of MHC-encoded determinants recognized by hapten- and allo-specific cytotoxic T cells was analyzed with the use of cell lines expressing recombinant H-2D(d) and H-2L(d) MHC products. Bulk cultures of CTL against TNP-self, FITC-self, and AED-self recognized self determinants associated with the N/C1 domains of both D(d) and L(d) products. A number of allo- and hapten-specific CTL clones were also tested for recognition of the recombinant MHC products. The allo clones specific for L(d) or D(d) antigens recognized the respective N/C1-associated determinants. In addition, all clones generated against H-2(q) and known to cross-react with H-2D(d) antigens recognized determinants associated with the N/C1-associated D(d) determinants. Thus, some of the results obtained with CTL parallel, whereas others contrast with, those findings obtained with monoclonal anti-H-2 antibodies. Similar to the observations made with the monoclonal antibodies, no determinant as defined by T cells has been found to be lost as a result of the interaction between the N/C1 and C2/M domains of the L(d) and D(d) proteins. Nor did our studies detect the presence of new antigens resulting from the interaction of these gene products. However, the present T cell findings continue to contrast previous results demonstrating that antibody interaction with class I products includes recognition of C2/M-associated epitopes.