Activation of bovine B cells via surface immunoglobulin M cross-linking or CD40 ligation results in different B-cell phenotypes.
Experiments reported herein demonstrate that activation of bovine B cells via surface immunoglobulin M (sIgM) cross-linking, analogous to T-cell independent (TI-2) antigenic stimulation, results in the expression of CD5. Interestingly, in the presence of CD40 ligand, sIgM-mediated induction of CD5 on B cells was inhibited. These findings indicate that activation of bovine B cells via B-cell receptor (BCR) cross-linking results in a CD5+ B-cell phenotype and that CD40 signalling is inhibitory to this process. Analysis of cytokine mRNA indicates that bovine B cells constitutively express tumour necrosis factor-alpha (TNF-alpha) and interleukin (IL)-1beta transcripts in vitro, while IL-10 mRNA expression is induced following sIgM cross-linking. IL-12 p40 transcripts were produced by B cells activated by CD40, but not by BCR, ligation. Analysis of cytokine receptor mRNA indicates that activation through CD40, in the presence or absence of IgM cross-linking, results in increased IL-4 receptor-alpha (IL-4Ralpha), IL-13Ralpha1 and interferon-alpha receptor 1 (IFN-alphaR1) mRNA levels. Overall, these findings suggest that activation of bovine B cells through BCR cross-linking yields an activation phenotype that differs substantially from that of B cells activated through CD40.
Haas
K M
KM
Department of Molecular Microbiology and Immunology, School of Medicine, College of Veterinary Medicine, University of Missouri-Columbia, Columbia, MO 65211, USA.
Estes
D M
DM
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D019013:CD40 Antigens / Q000276:immunology*; D023201:CD40 Ligand; D018956:CD5 Antigens / Q000378:metabolism; D002417:Cattle / Q000276:immunology*; D018929:Cell Culture Techniques; D005260:Female; D005786:Gene Expression Regulation / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology*; D016130:Immunophenotyping; D008024:Ligands; D008213:Lymphocyte Activation / Q000276:immunology*; D008297:Male; D008562:Membrane Glycoproteins / Q000276:immunology; D012333:RNA, Messenger / Q000235:genetics; D018121:Receptors, Cytokine / Q000378:metabolism
D019013:CD40 Antigens; D018956:CD5 Antigens; D007075:Immunoglobulin M; D008024:Ligands; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D018121:Receptors, Cytokine; D023201:CD40 Ligand