Humoral helper activity for B-cell differentiation released from non-Hodgkin's lymphoma cells having both SRBC and complement receptors in the pokeweed mitogen system.

The majority of lymphoid cells from a patient with non-Hodgkin's lymphoma with leukemic transformation were demonstrated to carry receptors for both sheep erythrocytes and complements by the combined rosette assay using neuraminidase-treated sheep erythrocytes and complement-coated zymosan beads. Most of them were considered morphologically lymphoblasts and were positive for acid phosphatase staining. Terminal deoxynucleotidyl transferase activity was not detected in these cells. Lymphoid cells from this patient did not respond to the stimulation with phytohemagglutinin-P, concanavalin-A, and pokeweed mitogen (PWM). When these cells were cultured with PWM for 7 days, no plasma cell was generated. Although only a few plasma cells were generated in the PWM-stimulated culture of normal purified B cells alone, the addition of the patient's cells to purified normal B cells resulted in a markedly enhanced generation of plasma cells in response to PWM, as was the case with normal T cells. But leukemic cells either from a patient with T-cell leukemia not having complement receptors or from a patient with null-cell leukemia showed no enhancing ability in B-cell differentiation. In addition, the culture supernates of the patient's cells obtained after 24-hr PWM stimulation had an ability to promote B-cell differentiation comparable in activity to those from the PWM-stimulated normal T cells.