The gastrointestinal tract is a major portal of entry for many pathogens, including the protozoan parasite Toxoplasma gondii. Billions of people worldwide have acquired T. gondii at some point in their life, and for the vast majority this has led to latent infection in the central nervous system. The first line of host defense against Toxoplasma is located within the intestinal mucosa. Appropriate coordination of responses by the intestinal epithelium, intraepithelial lymphocytes, and lamina propria cells results in an inflammatory response that controls acute infection. Under some conditions, infection elicits bacterial dysbiosis and immune-mediated tissue damage in the intestine. Here, we discuss the complex interactions between the microbiota, the epithelium, as well as innate and adaptive immune cells in the intestinal mucosa that induce protective immunity, and that sometimes switch to inflammatory pathology as T. gondii encounters tissues of the gut.

胃肠道是许多病原体（包括原生动物寄生虫）的主要入口 弓形虫。全球已有数十亿人获得弓形虫在他们生命中的某个时刻，对于绝大多数人来说，这导致了中枢神经系统的潜在感染。针对主机的第一道防线弓形虫位于肠粘膜内。肠上皮，上皮内淋巴细胞和固有层细胞对反应的适当协调会导致控制急性感染的炎症反应。在某些情况下，感染会引起细菌性营养不良和肠道中免疫介导的组织损伤。在这里，我们讨论了微生物群，上皮细胞以及肠粘膜中先天性和适应性免疫细胞之间的复杂相互作用，这些相互作用会诱导保护性免疫，有时会转变为炎症病理。弓形虫 遇到肠道组织。