title: Mitogenic proteins of pokeweed. II. The differentiation of human peripheral blood B lymphocytes stimulated with purified pokeweed mitogens (Po-2 and Po-6) from pokeweed, Phytolacca octandra.
abstract: Purified pokeweed mitogens, Po-2 and Po-3, extracted from Phytolacca octandra, stimulated plasma cell formation in cultures of human peripheral blood lymphocytes. Plasma cell formation did not occur in cultures of purified B cells but was dependent on T-cell help. High T-cell numbers, however, suppressed plasma cell formation in mixed B- and T-cell cultures stimulated with Po-2. T-cell helper function was exerted across a major histocompatibility barrier and was not dependent on T-cell proliferation. Soluble helper factor(s) from activated T cells were not demonstrated. Po-3 was an effective B-cell stimulant only at concentrations between 0.1 and 1.0 micrograms/ml. In contrast, relatively high concentrations of Po-2 (50--100 micrograms/ml) were required to induce B-cell differentiation. More plasma cells were generated in Po-2-stimulated cultures than in Po-3-stimulated cultures and this was thought to reflect the more aggregated state of Po-2.
mesh_terms: D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D002454:Cell Differentiation; D002478:Cells, Cultured; D006801:Humans; D008213:Lymphocyte Activation; D037121:Plant Lectins; D010944:Plants / Q000032:analysis; D010950:Plasma Cells / Q000166:cytology; D011043:Pokeweed Mitogens / Q000494:pharmacology*; D012621:Seasons; D013601:T-Lymphocytes / Q000166:cytology
chemical_list: D037121:Plant Lectins; D011043:Pokeweed Mitogens