B lymphocyte receptors and polyphosphoinositide degradation.
Resting B lymphocytes can be activated and induced to proliferate by antibodies against their antigen receptors (anti-lg). We demonstrate an early increase in the level of [3H]inositol trisphosphate in [3H]inositol-labeled murine B cells, which suggests breakdown of phosphatidylinositol bisphosphate by phospholipase C. In line with this, the level of [3H]1,2-diacylglycerol was also elevated after incubation of [3H]arachidonic-acid-labeled B cells with anti-Ig. Anti-lg also caused a rapid increase in the level of cytosolic Ca2+ in B cells. In contrast, two other polyclonal B cell activators, lipopolysaccharide and phorbol myristate acetate, failed to induce any of these effects. Our results suggest that anti-lg may induce B cell growth via phosphoinositide degradation and Ca2+ mobilization, and that phorbol myristate acetate, and possibly lipopolysaccharide, bypass these initial events.
M K
MK
Bijsterbosch
C J
CJ
Meade
G A
GA
Turner
G G
GG
Klaus
D000818:Animals; D000906:Antibodies / Q000502:physiology*; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002712:Chlorides / Q000494:pharmacology; D004075:Diglycerides / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008094:Lithium / Q000494:pharmacology; D018021:Lithium Chloride; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols / Q000378:metabolism*; D012313:RNA / Q000096:biosynthesis; D011947:Receptors, Antigen, B-Cell / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
C011439:1,2-diacylglycerol; D000906:Antibodies; D002712:Chlorides; D004075:Diglycerides; D008070:Lipopolysaccharides; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols; D011947:Receptors, Antigen, B-Cell; D012313:RNA; D008094:Lithium; D018021:Lithium Chloride; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium