CD36 is differentially expressed on B cell subsets during development and in responses to antigen.
Of a number of mAbs made by immunization with sort-purified marginal zone (MZ) B cells, one was shown to recognize the mouse scavenger receptor CD36. Although CD36 is expressed by most resting MZ B cells and not by follicular and B1 B cells, it is rapidly induced on follicular B cells in vitro following TLR and CD40 stimulation. In response to T-independent and T-dependent Ag challenge, we found that CD36 was expressed on IgM+ plasma cells, but down-regulated on isotype-switched plasma cells in vivo. Although development, localization, and phenotype of MZ B cells in CD36-/- mice appeared normal, there was a minor block in the transitional stages of mature B cell development. In both primary and secondary Ab responses to heat-killed Streptococcus pneumoniae (R36A strain), both phosphoryl choline (PC)-specific IgM and IgG levels in CD36-/- mice were slightly reduced compared with wild-type mice. In addition, mice deficient in both TLR2 and CD36 produced significantly reduced levels of anti-PC IgG titers than those of single gene-deficient mice, suggesting that they may cooperate in an anti-PC Ab response. Collectively, these results show that CD36 does not affect the development of B cells, but modulates both primary and secondary anti-PC Ab responses during S. pneumoniae infection similarly to TLR2.
Won
Woong-Jai
WJ
Division of Developmental and Clinical Immunology, Department of Microbiology, University of Alabama at Birmingham 35294-2182, USA.
Bachmann
Martin F
MF
Kearney
John F
JF
D000818:Animals; D000907:Antibodies, Bacterial / Q000378:metabolism; D000955:Antigens, T-Independent / Q000276:immunology*; D016175:B-Lymphocyte Subsets / Q000276:immunology*; D018955:CD36 Antigens / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D007074:Immunoglobulin G / Q000378:metabolism; D008213:Lymphocyte Activation; D051379:Mice; D008817:Mice, Mutant Strains; D010950:Plasma Cells / Q000276:immunology*; D013296:Streptococcus pneumoniae / Q000276:immunology; D051195:Toll-Like Receptor 2 / Q000378:metabolism
D000907:Antibodies, Bacterial; D000955:Antigens, T-Independent; D018955:CD36 Antigens; D007074:Immunoglobulin G; C493486:Tlr2 protein, mouse; D051195:Toll-Like Receptor 2