Stimulation of gamma-globulin synthesis and specific antibody production by a factor released by activated lymphocytes.

Abstract

By using a radioactive immune coprecipitation technique, supernatants of lymph node cells from immunized rabbits incubated with keyhole limpet hemocyanin (KLH) were shown to enhance γ-globulin synthesis and anti-KLH antibody production of KLH-primed and nonprimed lymphoid cells from the peripheral blood and lymph nodes in the presence of KLH in vitro. Similarly, when KLH-stimulated supernatants were added both to BSA-primed and nonprimed lymphocyte cultures in the presence of BSA, increases in γ-globulin and anti-BSA synthesis were observed. The data presented provide evidence that a soluble factor is released by antigen-stimulated lymphocytes which enhances immunoglobulin and specific antibody production in a nonspecific manner. The evidence obtained suggests that the factor may be a lymphokine which either directly or indirectly stimulates bone marrow-derived lymphocyte function in both the primary and secondary responses.