Human B cell differentiation. II. Suppression by T cells of T-dependent and T-independent plasma cell maturation.
In vitro human plasma cell generation induced by both T-dependent (PWM) and T-independent (NWSM) mitogens was found to be suppressed by peripheral blood lymphocytes preincubated with human aggregated IgG. T cells, but not B lymphocytes, were able to mediate the suppressive activity; since aggregated (Fab)'2 fragments were found unable to generate suppressor cells, it was concluded that the suppressor cell was a T lymphocyte bearing Fcgamma receptors. These cells appeared to be largely radiosensitive. In most cases the proliferative responses remained unchanged. Since NWSM-induced activation is not dependent on the presence of T cells, these results show that, at least in this case, T cells exert their suppressor function directly on B lymphocytes. Whether PWM-induced B cell differentiation is suppressed by the same mechanism or/and by inactivation of T helper lymphocytes remains under investigation.
D001402:B-Lymphocytes / Q000166:cytology*; D002454:Cell Differentiation; D006801:Humans; D007140:Immunoglobulin Fab Fragments; D007074:Immunoglobulin G; D009615:Nocardia / Q000276:immunology; D010950:Plasma Cells / Q000166:cytology*; D011043:Pokeweed Mitogens / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology*
D007140:Immunoglobulin Fab Fragments; D007074:Immunoglobulin G; D011043:Pokeweed Mitogens