DC-SIGN固有免疫调节及其表达调控机制研究进展

Research progress on DC-SIGN medicated innate immunoregulation and regulatory mechanism of its expression

DC-SIGN(DC-specific ICAM-3-grabbing non integrin,CD209)系C型凝集素家族主要成员,具有模式识别受体和介导细胞黏附功能。DC-SIGN可通过分子中凝集素糖识别域,识别多种病原体的外源性和机体内源性抗原以及细胞表面黏附分子(ICAM-2,3)中甘露糖或岩藻糖的糖基团,并对话协调Toll样受体等,介导树突状细胞(DC)等参与病原体或肿瘤细胞的免疫逃逸;也可调节DC黏附迁移并在炎症启动中激活初始T细胞免疫应答。因而,作为天然免疫分子介导基础,DC-SIGN在DC参与的感染性和炎症性疾病等的正负免疫调节中发挥了关键作用。目前有关DC-SIGN免疫调节效应涉及的信号转导以及分子表达调控机制尚未完全阐明,就相关进展作一综述。

DC-SIGN （dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin） belongs to the major members of C-type lectin family, which is a PRR （pattern recognition receptor） and can mediate cell adhesion. DC-SIGN can specifically recognize glycoconjugates containing mannose or fucose in various exogenous antigen of pathogens, endogenous self-antigen and intercellular adhesion molecule 2,3 （ICAM-2, 3） by its lectin carbohydrate recognition domain. Moreover, it is also involved in immune escape of tumor cell or pathogens mediated by dendritic cells （DCs） through cross-talking with Toll like receptors. In the initial response of inflammation, DC-SIGN modulates the adhesion and migration of DCs to activate naive T-cell. Therefore, as an innate immune molecule, DC-SIGN plays an crucial role in infectious and inflammatory diseases through its positive and negative immunoregulatory effects on DCs. However, the immunoregulation mechanisms of DC-SIGN including signal transduction and expression regulation have not been fully elucidated. We have reviewed some progress in this field here.