Antigen-induced changes in phospholipid metabolism in antigen-binding B lymphocytes.
Previous studies have demonstrated a marked change in the metabolism of phospholipids (PL) after activation of resting B lymphocytes with anti-immunoglobulin (anti-Ig). In this study we examined PL metabolism in highly purified trinitrophenyl (TNP)-binding B cells after their activation with various forms of TNP-carrier protein. Such cells show similar changes in PL metabolism when stimulated with either antigen or anti-Ig, i.e., increased incorporation of 32PO4 into phosphatidic acid and phosphatidyl inositol (PI) but not phosphatidyl choline, phosphatidyl ethanolamine, or phosphatidyl serine. We have demonstrated that these responses to antigen are TNP-specific and dose-related between 1 and 50 micrograms/ml, producing up to a 2.5-fold stimulation of 32PO4 incorporation into PI. The PL response is also directly related to the density of TNP on the carrier and can be augmented by additional cross-linking of the carrier protein. These data suggest that cross-linking of surface Ig by antigen induces a change in PL metabolism as an early event in B cell activation.
D000818:Animals; D000941:Antigens / Q000502:physiology*; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D002454:Cell Differentiation; D004306:Dose-Response Relationship, Immunologic; D006241:Haptens; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation; D051379:Mice; D010743:Phospholipids / Q000378:metabolism*; D011947:Receptors, Antigen, B-Cell / Q000502:physiology*; D013329:Structure-Activity Relationship; D013601:T-Lymphocytes / Q000276:immunology
D000941:Antigens; D006241:Haptens; D008070:Lipopolysaccharides; D010743:Phospholipids; D011947:Receptors, Antigen, B-Cell