ANTIIMMUNOGLOBULIN ANTIBODIES INDUCE APOPTOSIS IN IMMATURE B-CELL LYMPHOMAS

WEHI‐231 and CH31 are phenotypically immature sIgM+ murine B cell lymphomas whose growth is inhibited by anti‐immunoglobulin (Ig) antibodies. These lines have therefore been used as models for studying the role of surface Ig receptors in the induction of B cell tolerance. We show here that anti‐γ antibodies induce DNA cleavage into oligonucleosomal fragments characteristic of programed cell death (apoptosis) in both cell lines, although WEHI‐231 cells are less susceptible than CH31. This effect was reversed by lipopolysaccharide, in agreement with the known effects of lipopolysaccharide on anti‐Ig‐induced growth inhibition. These results therefore indicate that these lymphomas afford a potentially interesting model to study the mechanisms of programed cell death induced by ligation of the antigen receptors on normal B cells. Copyright © 1990 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim