Phenotypic convergence and divergence of surface immunoglobulin and CD40 signals.
Both anti-CD40 antibodies and anti-immunoglobulin (Ig) coupled to Sepharose induced proliferation of resting B cells and suppressed lipopolysaccharide (LPS)-induced B-cell differentiation to immunoglobulin secretion at comparable levels determined with the plaque-forming assay and Ig RNA steady state levels. Anti-CD40 antibodies also increased the proliferation of B cells stimulated by T helper cells in vitro while suppressing their differentiation to Ig secretion. Further, B cells preactivated by anti-Ig, anti-CD40 or a combination of the two mitogens could be restimulated by anti-CD40 but not by anti-Ig antibodies. Phenotypic divergence of Ig and CD40 signals regarding surface expression of activation markers was observed. Restimulation of anti-Ig- or anti-CD40-prestimulated cells with anti-Ig induced apoptosis whereas apoptosis could be inhibited when cells were recultivated with anti-CD40.
Axcrona
K
K
Department of Cell and Molecular Biology, Lund University, Sweden.
Akerblad
P
P
Leanderson
T
T
D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D001402:B-Lymphocytes / Q000276:immunology; D019013:CD40 Antigens / Q000502:physiology*; D002453:Cell Cycle / Q000502:physiology; D015536:Down-Regulation; D005260:Female; D018796:Immunoconjugates / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010641:Phenotype; D011947:Receptors, Antigen, B-Cell / Q000502:physiology*; D012685:Sepharose / Q000494:pharmacology; D015398:Signal Transduction / Q000502:physiology*; D013601:T-Lymphocytes / Q000276:immunology
D000906:Antibodies; D019013:CD40 Antigens; D018796:Immunoconjugates; D008070:Lipopolysaccharides; D011947:Receptors, Antigen, B-Cell; D012685:Sepharose