Specificity of Cytotoxic Effector Cells Directed against Trinitrobenzene Sulfonate-modified Syngeneic Cells

Cell-mediated lympholysis (CML) 1 has been generated in vitro against trinitrophenyl (TNP)-modified syngeneic murine spleen cells (1). The specificity of the effectors generated is such that the stimulater and target cells must beth be modified by the same agent (2, 3)1 and must also express the same H-2K and/or H-2D haplotypes (4, 5). In previous studies of the specificity of the CML effecters directed against TNP self, the modifying agents were coupled to cell surface proteins via covalent linkage, primarily to the amino groups of lysines (6). The present report describes experiments in which TNP stearoyl dextran was inserted into the lipid bilayer of mouse spleen cells (used as sensitizing cells) and lymphoid tumor cells (used as target cells) for the generation of effectors directed against self-modified cells. The results indicate that when quantitatively equivalent amounts of TNP are present on the cell surface either in the form of TNP stearoyl dextran (TSD) or as a result of direct covalent modification of the cell surface with trinitrobenzene sulfonate (TNBS), only the latter is immunogenic for the generation of a TNP self CML. Furthermore, the TSDmodified cells do not serve either as lysable targets or as inhibiting cells of effecters generated by sensitization with TNBS-modified syngeneic cells.