Abstract
Polyclonal activation of human B lymphocytes by LPS or protein A, alone or in combination or by Epstein-Barr virus (EBV), generates suppressive conditions that inhibit the response of human B lymphocytes to pokeweed mitogen (PWM), measured by the induction of immunoglobulin-secreting cells (PFC). Moreover, EBV-transformed B cell lines of normal or neoplastic (Burkitt lymphoma) origin also suppressed the PWM-induced immunoglobulin production of normal B cells. Cell separation experiments have shown that mitogen activated autologous B cells stimulate suppressor T cells in a similar way as B cell-derived lymphoblastoid cell lines. The significance of this phenomenon is considered in relation to the escape of the activating microorganism or virus from immune control and the occurrence of network interactions within the immune system.