Receptors for antigen on lymphoid cells. I. Immunoadsorption of plaque forming cells to poly L lysine fixed antigen monolayers

A method was developed for examining the binding specificities of plaque forming cells (PFC) which were immune to either goat red blood cell surface antigens or to the trinitrophenyl (TNP) haptenic group. Immune rat lymph node cells were plated on poly L lysine fixed red blood cell (RBC) monolayers which functioned dually as immunoadsorbents and as plaque indicators of both adherent and nonadherent PFC populations. Anti TNP PFC demonstrated marked specific adherence to TNP GRBC. The adherence was optimal following a 30 min adsorption phase and was essentially independent of the adsorption temperature in the 4° to 37° C range. Specific adherence of anti GRBC PFC to GRBC monolayers at 4° C was not detectable, but did occur at adsorption temperatures of 25° or 37° C. Temperature differences in specific adsorption in the two systems were not due simply to differences in the density of antigenic determinants on the adsorbing monolayers. Specific adherence of anti GRBC PFC at 4° C was able to occur in the presence of DEAE dextran, indicating the importance of surface charge effects. This immunoadsorbent indicator system provides a means of studying the recognition events occurring at the PFC surface.