title: High dose lipopolysaccharide triggers polarization of mouse thymic Th17 cells in vitro in the presence of mature dendritic cells.
abstract: Lipopolysaccharide (LPS) plays an important role in the activation of innate immune cells, leading to secretion of proinflammatory factors and bridging the adaptive immune system. Exposing total mouse thymic cells culture to LPS induced a unique expression profile of cytokines (IL-17A, IL-17F, and IL-22) and the essential ROR-γt master transcription factor, which suggested a preferential differentiation of thymocytes towards the Th17 cell phenotype. Th17-polarizing molecules (IL-23, IL-23R, IL-6, and TGF-β) and IL-17A(+)CD4(+) thymocytes were also specifically produced by the in vitro LPS-stimulation of thymic cells. Furthermore, both the expression of Th17 differentiation-related molecules and the frequency of Th17 cells were significantly up-regulated with increasing doses of LPS, as evidenced by quantitative RT-PCR and flow cytometric analysis, respectively. The expressions and frequency reached maximum levels when LPS exposure had been maintained at an extremely high concentration (100 μg/mL) for 48 h. On the other hand, depletion of thymic dendritic cells (DCs) blocked the LPS-induced polarization of thymus-derived Th17 cell lineage. Addition of bone marrow-derived DCs (BMDCs) to the purified immature CD4(+) CD62L(low) thymocytes culture recovered the switch towards Th17 cells, which synergistically prompted the cytotoxic activity of CD8(+) T cells. Taken together, our data indicates that high doses of LPS can promote the differentiation of mouse thymus-derived Th17 cells by a mechanism involving components associated with mature DCs.
authors.affiliation: Department of Immunology, Wuhan University School of Medicine, Wuhan University, Wuhan, PR China.
authors.forename: Lan
authors.initials: L
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Xiao
authors.forename: Yingcheng
authors.initials: Y
authors.lastname: Zheng
authors.forename: Ruijing
authors.initials: R
authors.lastname: Xiao
authors.forename: Guoguo
authors.initials: G
authors.lastname: Zhu
authors.forename: Mei
authors.initials: M
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Shu
authors.initials: S
authors.lastname: Peng
authors.forename: Xinti
authors.initials: X
authors.lastname: Tan
authors.forename: Yuling
authors.initials: Y
authors.lastname: He
authors.forename: Jinquan
authors.initials: J
authors.lastname: Tan
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D019070:Cell Lineage; D002478:Cells, Cultured; D018920:Coculture Techniques; D003713:Dendritic Cells / Q000276:immunology*; D005260:Female; D020381:Interleukin-17 / Q000096:biosynthesis; D053759:Interleukin-23 / Q000096:biosynthesis; D015850:Interleukin-6 / Q000096:biosynthesis; D007378:Interleukins / Q000096:biosynthesis; D008070:Lipopolysaccharides / Q000276:immunology*; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3 / Q000096:biosynthesis; D058504:Th17 Cells / Q000276:immunology*; D060168:Thymocytes / Q000166:cytology / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000096:biosynthesis; D000097043:Interleukin-22
chemical_list: D020381:Interleukin-17; D053759:Interleukin-23; D015850:Interleukin-6; D007378:Interleukins; D008070:Lipopolysaccharides; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3; D016212:Transforming Growth Factor beta; D000097043:Interleukin-22