In vitro immune responses: effects of masking lymphocyte membrane components

Mouse peripheral blood cells and fetal liver cells were cultured with a variety of antigens or with allogeneic cells together with antisera raised against H-2 specificities, θ, or mouse immunoglobulins. All responses dependent upon thymus-passaged cells were profoundly impaired by antisera putatively directed against H-2 specificities. On the other hand, the responses by fetal liver cells (B cells) to these same “thymus-dependent” antigens or by blood cells from adult mice to “thymus-independent” antigens were not affected by the same treatment. The heterologous antiserum to mouse immunoglobulins produced a moderate reduction in the responses by blood cells and fetal liver cells to all antigens tested. The AKr-anti-θC3H serum either was without effect or it slightly increased the response to these same antigens.