论文部分内容阅读
分泌型免疫球蛋白A（ SIgA）是由J链连接成的多聚体 IgA与分泌片段结合后形成的复合物，主要存在于乳汁、胃肠液、呼吸道分泌液等外分泌液中，是黏膜免疫的主要抗体，它能有效地阻断病原体对深层组织的感染和入侵，是机体抵御有害物质的第一道防线。 SIgA是黏膜表面分泌量最多的抗体，它能在细胞内中和病原微生物，并且可以穿过上皮细胞，有效清除黏膜部位的免疫复合物及上皮细胞内的抗原。现就SIgA的结构、合成与分泌、生物学功能以及临床应用等方面作一综述，以阐明SIgA在黏膜免疫中所起的重要作用。“,”Secretory immunoglobulin A( SIgA) is a compound composed by a polymer IgA molecule con -nected with a J chain and secretory component,which mainly exists in the external secretions,such as milk, respiratory secretions,gastrointestinal secretions and so on.Moreover SIgA is the vital antibody of mucosal immunity,which can effectively prevent body from infection and invasion of pathogens.Therefore it serves as a first line of defense from harmful substances.The number of the secretory volume of SIgA is the most on the mucosal surface,and it can neutralize pathogens within cell,and it also can go through the epithelial cells to effectively clear immune complexes and antigens on the mucosal surface .Here is to make a review of the structure,synthesis and secretion,biological functions and clinical application of SIgA ,with the aim to illus-trate the importance of SIgA in mucosal immunity.