title: CD43 (S7) expression identifies peripheral B cell subsets.
abstract: CD43 (leukosialin) expression has previously been demonstrated on the surface of developing B cells in mouse bone marrow and on plasma cells induced in vitro, but not on peripheral B cells in spleen. Here we show that CD43, as recognized by mAb S7, is indeed expressed on a small population of splenic B cells. Flow cytometric phenotyping of normal mice and radiation chimeras reveals that CD43/S7 is expressed on virtually all (> 90 to 95%) splenic B-1 cells and the majority of peritoneal B-1 cells, but not on conventional B cells. The expression of CD43/S7, in conjunction with other cell surface markers, clearly distinguishes B-1 cells from follicular, marginal zone, and immature B cells in the unstimulated adult spleen and permits further phenotyping of these subsets. The phenotype of splenic and peritoneal B-1 cells in normal BALB/c and BAB/25 mice is essentially identical with the exception that all peritoneal B-1 cells express CD11b (Mac-1) and some lack CD43/S7 and heat stable Ag (as detected by the mAb 53-10) expression. Although splenic B-1, marginal zone, and immature B cells share many phenotypic characteristics, these studies show that, in addition to CD43, they differ with respect to the expression levels of a variety of Ags including heat stable Ag, B220, and the B cell activation Ag B7.
authors.affiliation: Department of Microbiology, Columbia University, College of Physicians and Surgeons, New York, NY 10032-3702.
authors.forename: S M
authors.initials: SM
authors.lastname: Wells
authors.forename: A B
authors.initials: AB
authors.lastname: Kantor
authors.forename: A M
authors.initials: AM
authors.lastname: Stall
mesh_terms: D000375:Aging / Q000276:immunology; D000818:Animals; D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D016175:B-Lymphocyte Subsets / Q000276:immunology*; D001854:Bone Marrow Cells; D002478:Cells, Cultured; D005434:Flow Cytometry; D016130:Immunophenotyping; D051917:Leukosialin; D008070:Lipopolysaccharides / Q000494:pharmacology; D051379:Mice; D008815:Mice, Inbred Strains; D010529:Peritoneal Cavity / Q000166:cytology; D011828:Radiation Chimera; D012795:Sialoglycoproteins / Q000096:biosynthesis*; D013154:Spleen / Q000166:cytology
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D051917:Leukosialin; D008070:Lipopolysaccharides; D012795:Sialoglycoproteins; C497863:Spn protein, mouse