Effect of spleen-derived cells on autochthonous peripheral blood lymphocyte responses to mitogens in gastric cancer patients.

Lymphocyte-rich mononuclear cells and their fractions which were prepared from spleens removed at the time of total or proximal gastrectomy for gastric cancer were treated with mitomycin C, and their effect on autochthonous peripheral blood lymphocyte responses to phytohemagglutinin P and concanavalin A was assessed in coculture experiments. It was found that splenic mitomycin C-treated lymphocyte-rich mononuclear cells from certain gastric cancer patients had suppressor cell activity on peripheral blood lymphocyte responses to phytohemagglutinin P and concanavalin A and that the cells with the activity were either plastic dish-adherent cells or T-enriched cells alone or both of them. It was also found that splenic lymphocyte-rich mononuclear cells from certain gastric cancer patients had augmenting activity on peripheral blood lymphocyte responses to phytohemagglutinin P and that the cells which exerted the activity were either plastic dish-adherent cells or T-enriched cells or all of plastic dish-adherent cells and T- and B-enriched cells.