Functional heterogeneity of the Lyb-5- B cell subpopulation: mutant xid B cells and normal Lyb-5- B cells differ in their responsiveness to phenol-extracted lipopolysaccharide.
In the present study, responses stimulated by phenol-extracted lipopolysaccharide (LPS(phenol)) and butanol-extracted LPS (LPS(butanol)) were used to assess the possibility that xid B cells might not be identical to the Lyb-5- B cells present in normal mice. It was found that xid B cells responded well only to LPS(butanol) whereas normal B cells responded well to both LPS(butanol) and LPS(phenol). Thus, LPS(butanol) appeared to be a TI-1 antigen and LPS(phenol) appeared to be a TI-2 antigen. In contrast to classical TI-2 responses, however, responses stimulated by LPS(phenol) did not exhibit a stringent requirement for accessory cells. Furthermore, if LPS(phenol) were a classical TI-2 antigen, it should only activate Lyb-5+ B cells. To determine if the responsiveness of normal B cells to LPS(phenol) were due, at least in part, to the stimulation of normal Lyb-5- B cells, the responsiveness of normal neonatal B cells and normal adult B cells that had been pretreated with anti-Lyb-5.1 + C was assessed. It was found that both normal neonatal B cells and normal adult Lyb-5- B cells did respond well to LPS(phenol). Thus, even though LPS(phenol) does not stimulate xid B cells, these data demonstrate that LPS(phenol) is different from other TI-2 antigens. More importantly, these data also demonstrate that xid B cells and normal Lyb-5- B cells are not identical. It is hypothesized that the normal Lyb-5- B cell subpopulation is heterogeneous, consisting of an Lyb-5(1)- and an Lyb-5(2)-B cell subset with the xid mutation blocking the differentiation of Lyb-5(1)-B cells into Lyb-5(2)-B cells.
D000818:Animals; D000921:Antibody-Producing Cells / Q000276:immunology; D000942:Antigens, Bacterial / Q000276:immunology; D015478:Antigens, Heterophile / Q000276:immunology*; D000950:Antigens, Ly / Q000276:immunology*; D001402:B-Lymphocytes / Q000145:classification / Q000276:immunology*; D005260:Female; D006462:Hemolytic Plaque Technique; D007700:Kinetics; D008070:Lipopolysaccharides / Q000276:immunology* / Q000494:pharmacology; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D008817:Mice, Mutant Strains; D008819:Mice, Nude; D050378:T-Lymphocytes, Regulatory / Q000276:immunology
D000942:Antigens, Bacterial; D015478:Antigens, Heterophile; D000950:Antigens, Ly; D008070:Lipopolysaccharides