免疫介导的胃肠线虫驱除机制研究进展

Progress on New Mechanisms of Immune-mediated Expulsion of Gastrointestinal Nematodes

寄生线虫对人类的侵染一直是公认的健康问题,给全球经济造成了重大损失。近年来,人们利用肠道线虫侵染鼠模型,研究寄主如何通过免疫系统调控对线虫侵染的抗性、敏感性及相关的细胞分子基础,取得了一定的成果。寄主对线虫侵染的敏感性是由T细胞1类细胞因子反应调控的,而对寄生在肠道的成虫的免疫性则严格依赖2类细胞因子反应。然而,在肠道微环境中,2类细胞因子是如何引发逐出蠕虫的免疫效应的,至今仍不清楚。文章综述了寄主对线虫的主要免疫效应的研究进展,具体讨论两种近期发现的依赖2类细胞因子的免疫分子,内源凝集蛋白、抵抗素类似分子及其在逐出线虫过程中的作用,以及由肠道上皮细胞翻转调控逐出线虫的机制。

Parasitic nematode infections of human continue to impose a significant public health and economic burden worldwide. Murine models of intestinal nematode infection have proved to be relevant and tractable systems to define the cellular and molecular basis on how the host immune system regulates resistance and susceptibility to infection. Results indicate that susceptibility to chronic infection is propagated by T helper cell type 1 cytokine responses, while immunity to intestinal-dwelling adult nematode worms is critically dependent on type 2 cytokine response. However, the immune effector mechanisms elicited by type 2 cytokines in the gut microenvironment that precipitate worm expulsion have remained elusive. This review focused on new studies that implicate host intestinal epithelial cells as one of the dominant immune effector cells against this group of pathogens. Specifically, two recently identified type 2 cytokine-dependent immune molecules including the intelectins and the resistin-like molecules, and their roles in expulsing nematodes and cytokine regulation of intestinal epithelial cell turnover,were discussed.