A diverse group of antimicrobial proteins (AMPs) helps protect the mammalian intestine from varied microbial challenges. We show that small proline-rich protein 2A (SPRR2A) is an intestinal antibacterial protein that is phylogenetically unrelated to previously discovered mammalian AMPs. In this study, SPRR2A was expressed in Paneth cells and goblet cells and selectively killed Gram-positive bacteria by disrupting their membranes. SPRR2A shaped intestinal microbiota composition, restricted bacterial association with the intestinal surface, and protected against Listeria monocytogenes infection. SPRR2A differed from other intestinal AMPs in that it was induced by type 2 cytokines produced during helminth infection. Moreover, SPRR2A protected against helminth-induced bacterial invasion of intestinal tissue. Thus, SPRR2A is a distinctive AMP triggered by type 2 immunity that protects the intestinal barrier during helminth infection.

中文翻译：

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富含脯氨酸的小蛋白 2A 是蠕虫感染期间部署的肠道杀菌蛋白

一组不同的抗菌蛋白 (AMP) 有助于保护哺乳动物肠道免受各种微生物挑战。我们表明富含脯氨酸的小蛋白 2A (SPRR2A) 是一种肠道抗菌蛋白，在系统发育上与先前发现的哺乳动物 AMP 无关。在这项研究中，SPRR2A 在潘氏细胞和杯状细胞中表达，并通过破坏革兰氏阳性细菌的膜选择性地杀死它们。SPRR2A 塑造肠道微生物群组成，限制细菌与肠道表面的结合，并防止单核细胞增生李斯特菌感染。SPRR2A 与其他肠道 AMP 的不同之处在于它是由蠕虫感染期间产生的 2 型细胞因子诱导的。此外，SPRR2A 保护肠道组织免受蠕虫诱导的细菌入侵。因此，SPRR2A 是一种独特的 AMP，由 2 型免疫触发，可在蠕虫感染期间保护肠道屏障。