The Role of Adherent Cells in the Immune Response.

Abstract

The primary immune response to sheep erythrocytes in adherent cell-depleted cultures was restored by adding a critical number of peritoneal ceils. Complete substitution was achieved also with supernatants from allogencic and syngeneic peritoneal cells. Both living fibroblasts and supernatants from fibroblast cultures were found to be highly efficient substitutes for adherent cells in both syngeneic and allogeneic systems. Supernatants from non-antigen-treated peritoneal cells and fibroblasts caused increased DNA synthesis and induction of polyclonal antibody synthesis in normal spleen cells. Thus, adherent cells need not function in the immune response by presenting antigen to the B cells via ‘IgT’ or by releasing signal-2 activity, which acts on lymphocytes that have already received signal 1.