Induction of immunoglobulin and antigen-dependent antibody synthesis in human lymphocytes, using supernatants from mitogen-stimulated cultures

Supernatants derived from pokeweed mitogen-stimulated peripheral blood lymphocytes were freed of lectin by passage over an antibody column: the eluate contained < 2 ng/ml of PWM, measured by radioimmunoassay. In serum-free medium, these supernatants induce B-cell but not T-cell proliferation. Maximum proliferation is seen only if the B cells are co-cultured with irradiated T cells. The supernatants induce polyclonal immunoglobulin production, and in the presence of a soluble protein antigen (tetanus toxoid) they also induce specific antibody synthesis, in donors immunized up to 18 months previously.