Recirculating and sessile B cell populations in normal and CBA/N mice.
Chromosomally distinguishable syngeneic mice were parabiosed and the resultant chimerism was followed for 6 weeks in the lymphoid organs, by culturing their cells with polyclonal mitogens, lipopolysaccharide (LPS) for B cells and phytohemagglutinin (PHA) for T cells. As expected of a recirculating population, the T cells equilibrated completely. The B cells in lymph nodes (LN) and Peyer's patches (PP) also equilibrated completely, suggesting that they too are recirculating. B cells in the spleen and blood, however, did not equilibrate over this period. After separation of parabiosed mice, the percentage of partner cells in both the recirculating T and B lymphocyte populations declined steadily, but it continued to rise in the LPS-responsive populations in spleen and peripheral blood suggesting that they were derived from precursor populations which were themselves chimeric. Injection of lymphocytes into CBA/Ca or CBA/N mice showed that LPS-responsive populations in LN and spleen localized differently. These results have been interpreted as demonstrating two major populations of LPS-responsive B lymphocytes in the mouse, one recirculating and the other sessile. The recirculating population appears to be the only LPS-responsive population in LN and PP. In the spleen, however, the recirculating cells constitute about a quarter of the LPS-responsive cells, while the rest are sessile cells. The relationship between these two populations has yet to be clarified. CBA/N mice are deficient in both populations but the sessile one appears to be more severely depleted.
D000818:Animals; D001402:B-Lymphocytes / Q000145:classification / Q000502:physiology*; D002452:Cell Count; D002678:Chimera; D003427:Cross Circulation; D008070:Lipopolysaccharides / Q000494:pharmacology; D008198:Lymph Nodes / Q000166:cytology; D008213:Lymphocyte Activation; D017710:Lymphocyte Transfusion; D008297:Male; D051379:Mice; D008808:Mice, Inbred CBA / Q000235:genetics*; D010227:Parabiosis; D013154:Spleen / Q000166:cytology
D008070:Lipopolysaccharides