Lamina propria macrophages and dendritic cells differentially induce regulatory and interleukin 17–producing T cell responses
Lamina propria macrophages and dendritic cells differentially induce regulatory and interleukin 17–producing T cell responses
Timothy, L. D.,et al.2007. Nat. Immunol. 8, 1086 – 1094
Speaker : 朱晏廷 Time: 13:10~14:00, Dec. 19, 2007
Commentator : 謝奇璋 醫師 Place: Room 601
Abstract :
The intestinal immune system which responds to antigens such as harmal pathogens, commensal floras or food antigens is a complex network. Different antigen presenting cells (APCs) such as dendritic cells (DCs) and macrophages with different abilities can modulate T cell responses in lamina propria by secreting various cytokines. In this paper, the authors detect that abundant CD11b+CD11c- macrophages in lamina propria spontaneously produce IL-10 and are hyporesponsive to TLR stimulation. Lamina propria macrophages induce efficient differentiation of Foxp3+regulatory T cells (Treg cells) dependent on IL-10, retinoic acid and exogenous TGF-β. This promote tolerance , prevent intestinal inflammation, and suppress the differentiation of and TH1 and IL-17-producing T cells (TH17 cells). On the contrary, lamina propria CD11b+ DCs promote the generation of TH17 cells in the presence of TGF-β. However, these lamina propria macrophages may limit the lamina propria DCs to drive the generaion of IL-17-producing T cells. Thus, lamina propria macrophages induce the development of Foxp3+ Treg cells to promote tolerance and prevent intestinal inflammation. While, the lamina propria DCs promote the generation of TH17 cells that elicit immune responds. Therefore, the intestinal immune system considered to have a dynamic regulation between these APCs which may influence the balance between immune activation and toleration.
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