Hoft D F, Farrar P L, Kratz-Owens K, Shaffer D
Department of Internal Medicine, Saint Louis University Health Sciences Center, Missouri 63110, USA.
Infect Immun. 1996 Sep;64(9):3800-10. doi: 10.1128/iai.64.9.3800-3810.1996.
Trypanosoma cruzi is an intracellular parasite transmitted from a reduviid insect vector to humans by exposure of mucosal surfaces to infected insect excreta. We have used an oral challenge murine model that mimics vector-borne transmission to study T. cruzi mucosal infection. Although gastric secretions have microbicidal activity against most infectious pathogens, we demonstrate that T. cruzi can invade and replicate in the gastric mucosal epithelium. In addition, gastric mucosal invasion appears to be the unique portal of entry for systemic T. cruzi infection after oral challenge. The mucosal immune responses stimulated by T. cruzi gastric infection are protective against a secondary mucosal parasite challenge. This protective mucosal immunity is associated with increased numbers of lymphocytes that secrete parasite-specific immunoglobulin A. Our results document the first example of systemic microbial invasion through gastric mucosa and suggest the feasibility of a mucosal vaccine designed to prevent infection with this important human pathogen.
克氏锥虫是一种细胞内寄生虫，通过粘膜表面接触受感染昆虫排泄物，从锥蝽昆虫媒介传播给人类。我们使用了一种模拟媒介传播的口服攻击小鼠模型来研究克氏锥虫的粘膜感染。尽管胃分泌物对大多数传染性病原体具有杀菌活性，但我们证明克氏锥虫可以在胃粘膜上皮中侵入并复制。此外，胃粘膜侵袭似乎是口服攻击后全身性克氏锥虫感染的唯一入口途径。克氏锥虫胃部感染刺激的粘膜免疫反应对继发性粘膜寄生虫攻击具有保护作用。这种保护性粘膜免疫与分泌寄生虫特异性免疫球蛋白A的淋巴细胞数量增加有关。我们的结果记录了通过胃粘膜进行全身性微生物侵袭的首个例子，并表明设计用于预防这种重要人类病原体感染的粘膜疫苗的可行性。
