Characterization of self-reactive B cells by polyclonal B-cell activators.

Abstract
The aim of the present experiments was to investigate if the capacity of self-reactive B [bone marrow-derived] cells to be activated with different polyclonal B-cell activators (PBA) reflects the heterogeneity of the response as seen in all the Ig[immunoglobulin]positive cells. Mice were injected with dextran sulfate, lipopolysaccharide from Escherichia coli 055:B5, and purified protein derivate of turbercle bacteria RT32. The mice were then studied for complement-dependent cytotoxicity against syngeneic spleen cells (caused by the sera from injected mice) with regard to the different parameters used for characterization of B-cell subpopulations. The capacity of self-reactive B cells to secrete antibodies reflects the polyclonal-activating capacity of the PBA used. The implications of these findings for the understanding of the triggering mechanism of B lymphocytes and for self-nonself discrimination are discussed.