The relation between the T cells responsible for cell-mediated cytotoxic killing of mastocytoma cells and the helper-cell effect.

The relationship between T cells involved in cell-mediated immunity and antibody response of C57Bl/6J mice towards DBA/2 mastocytoma cells was investigated. Spleen cells primed with viable mastocytoma cells demonstrated marked cell-mediated cytotoxicity (CMC) in vitro, but antibody response of these cells to a hapten (TNP) conjugated to the allogeneic tumour cells in vitro was suppressed as compared with that of normal spleen cells. In contrast, spleen cells primed with frozen-thawed mastocytoma cells showed no CMC, but antibody response to the hapten in vitro of these cells was enhanced. C57Bl/6J mice primed with frozen-thawed mastocytoma cells produced more cytotoxic antibody than non-primed mice when immunized with viable mastocytoma cells. These results indicate that T cells involved in cell-mediated immunity and those involved in the antibody response to allogeneic mastocytoma cells are distinct.?222