Production of human heterophile antibodies. III. In vitro specific stimulation and immortalization of human lymphocytes.

The production of primary human specific antibody against an exogenous antigen by in vitro system was achieved in this study. Human lymphocytes were prepared from the lymphocytes of human spleen (SPL), tonsil (TL), and peripheral blood (PBL). These lymphocytes were stimulated by sheep red blood cells (SRBC) co-cultured with the appropriate number of allogeneic lymphocytes or fractionated T cells. Significant numbers of plaque forming cells (PFC) against SRBC were obtained. A major population of PFC responded to the stimulator RBC and a minor population of PFC responded to both SRBC and bovine red blood cells (BRBC). The culture of allogeneic combination of whole SPL or TL stimulated with SRBC produced PFC, but not that of whole PBL. Reconstitution of equal numbers of allogeneic separated B cells and T cells from PBL was required for a significant response. These specific antibody forming cells (AFC) were immortalized by Epstein Barr virus (EBV) infection and culture supernatant containing antigen-specific antibodies (anti-SRBC: Forssman antibody) were obtained after repeated cloning.