title: Toll-like receptor 4-mediated signaling regulates IL-7-driven proliferation and differentiation of B-cell precursors.
abstract: Lipopolysaccharide (LPS) is known to be a potent activator of mature B cells by signaling through Toll-like receptor 4 (TLR4). Its impact on early B-cell development, however, is not well defined. When comparing to C3H/HeN mice, TLR4-mutant C3H/HeJ mice showed an increase in the number of pro-B and pre-B cells in the bone marrow. When cultured in the presence of IL-7, the proliferation of pro-B and large pre-B cells was significantly inhibited by LPS, possibly due to reduced IL-7 receptor-α (IL-7Rα) expression. Meanwhile, the generation of IgM(+)/IgD(+) B cells was greatly enhanced in IL-7 cultures of pro-B and pre-B cells. Consistent with these results, treatment with LPS facilitated the progression of adoptively transferred B220(+)IgM(-)IgD(-) precursors into IgD(+) cells. Overall, these data suggest that LPS has a profound influence on early B-cell development, which may contribute to the deregulated B-cell development under physiological and pathological conditions such as bacterial infections.
authors: Department of Immunology, Key Laboratory of Medical Immunology of Ministry of Health, Peking University Health Science Center, Beijing, China.
authors: Qian
authors: Q
authors: Li
authors: Department of Immunology, Key Laboratory of Medical Immunology of Ministry of Health, Peking University Health Science Center, Beijing, China.
authors: Dongmei
authors: D
authors: Han
authors: Department of Immunology, Key Laboratory of Medical Immunology of Ministry of Health, Peking University Health Science Center, Beijing, China.
authors: Wei
authors: W
authors: Wang
authors: Department of Microbiology, Faculty of Basic Medical Sciences, Institute of Translational Medicine, Nanchang University, Nanchang, China.
authors: Xiaoqing
authors: X
authors: Liu
authors: Department of Immunology, Key Laboratory of Medical Immunology of Ministry of Health, Peking University Health Science Center, Beijing, China.
authors: Xiuyuan
authors: X
authors: Sun
authors: Department of Immunology, Key Laboratory of Medical Immunology of Ministry of Health, Peking University Health Science Center, Beijing, China.
authors: Jun
authors: J
authors: Zhang
authors: Department of Microbiology, Faculty of Basic Medical Sciences, Institute of Translational Medicine, Nanchang University, Nanchang, China.
authors: Rong
authors: R
authors: Li
authors: Department of Immunology, Key Laboratory of Medical Immunology of Ministry of Health, Peking University Health Science Center, Beijing, China.
authors: Yu
authors: Y
authors: Zhang
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D002454:Cell Differentiation / Q000235:genetics; D048708:Cell Growth Processes / Q000235:genetics; D002478:Cells, Cultured; D007072:Immunoglobulin D / Q000378:metabolism; D007075:Immunoglobulin M / Q000378:metabolism; D015851:Interleukin-7 / Q000276:immunology; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008070:Lipopolysaccharides / Q000276:immunology; D038041:Lymphopoiesis; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D009154:Mutation / Q000235:genetics; D054448:Precursor Cells, B-Lymphoid / Q000276:immunology*; D015398:Signal Transduction; D051197:Toll-Like Receptor 4 / Q000235:genetics / Q000276:immunology / Q000378:metabolism*
chemical_list: D007072:Immunoglobulin D; D007075:Immunoglobulin M; D015851:Interleukin-7; D008070:Lipopolysaccharides; C493487:Tlr4 protein, mouse; D051197:Toll-Like Receptor 4; D017493:Leukocyte Common Antigens