title: The modulatory effects of lipopolysaccharide-stimulated B cells on differential T-cell polarization.
abstract: Lipopolysaccharide (LPS) is a major component of environmental microbial products. Studies have defined the LPS dose as a critical determining factor in driving differential T-cell polarization but the direct effects of LPS on individual antigen-presenting cells is unknown. Here, we investigated the effects of LPS doses on naive B cells and the subsequent modulatory effects of these LPS-activated B cells on T-cell polarization. The LPS was able to induce a proliferative response starting at a dose of 100 ng/ml and was capable of enhancing antigen internalization at a dose of 1 microg/ml in naive B cells. Following LPS stimulation, up-regulation of the surface markers CD40, CD86, I-Ad, immunoglobulin M, CD54 and interleukin-10 production, accompanied by down-regulation of CD5 and CD184 (CXCR4) were observed in a LPS dose-dependent manner. Low doses (<10 ng/ml) of LPS-activated B cells drove T helper type 2 polarization whereas high doses (>0.1 microg/ml) of LPS-activated B cells resulted in T regulatory type 1 cell polarization. In conclusion, LPS-activated B cells acquire differential modulatory effects on T-cell polarization. Such modulatory effects of B cells are dependent on the stimulation with LPS in a dose-dependent manner. These observations may provide one of the mechanistic explanations for the influence of environmental microbes on the development of allergic diseases.
authors: Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors: Hui
authors: H
authors: Xu
authors: Lip Nyin
authors: LN
authors: Liew
authors: I Chun
authors: IC
authors: Kuo
authors: Chiung Hui
authors: CH
authors: Huang
authors: Denise Li-Meng
authors: DL
authors: Goh
authors: Kaw Yan
authors: KY
authors: Chua
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000378:metabolism; D001402:B-Lymphocytes / Q000276:immunology*; D016764:Cell Polarity / Q000276:immunology; D049109:Cell Proliferation; D002478:Cells, Cultured; D004306:Dose-Response Relationship, Immunologic; D004705:Endocytosis / Q000276:immunology; D016753:Interleukin-10 / Q000096:biosynthesis; D037181:Lectins, C-Type / Q000276:immunology; D008070:Lipopolysaccharides / Q000276:immunology*; D008213:Lymphocyte Activation / Q000276:immunology; D008211:Lymphocyte Cooperation / Q000276:immunology*; D000090323:Mannose Receptor; D037241:Mannose-Binding Lectins / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008822:Mice, Transgenic; D010873:Pinocytosis; D011956:Receptors, Cell Surface / Q000276:immunology; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D015854:Up-Regulation / Q000276:immunology
chemical_list: D000954:Antigens, Surface; D037181:Lectins, C-Type; D008070:Lipopolysaccharides; D000090323:Mannose Receptor; D037241:Mannose-Binding Lectins; D011956:Receptors, Cell Surface; D016753:Interleukin-10