Commensal-pathogen interactions in the intestinal tract: lactobacilli promote infection with, and are promoted by, helminth parasites.
Commensal-pathogen interactions in the intestinal tract: lactobacilli promote infection with, and are promoted by, helminth parasites.
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DOI：
10.4161/gmic.32155
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发表时间：
2014-07-01
期刊：
影响因子：
12.2
通讯作者：
Maizels RM
中科院分区：
文献类型：
--
作者：
Reynolds LA;Smith KA;Filbey KJ;Harcus Y;Hewitson JP;Redpath SA;Valdez Y;Yebra MJ;Finlay BB;Maizels RM
肠道微生物群在决定哺乳动物宿主的发育、代谢和免疫状态中是关键的。然而，肠道也可能容纳致病生物，包括在大多数热带国家高度流行的蠕虫寄生虫。微生物和蠕虫都必须逃避或操纵宿主的免疫系统才能在肠道环境中生存，但它们是否会影响彼此在宿主中的持久性仍然是未知的。我们现在表明，丰富的乳酸杆菌细菌与感染小鼠肠道线虫，Heligmosomoides polygyrus，以及与调节性T细胞（Treg）和Th 17的反应增强正相关。此外，H.多脑回增加了对H.多脑回感染，而不是在BALB/c小鼠，这是相对抵抗。在细菌gyrB基因座处对样品进行测序，鉴定出主要的乳杆菌属物种为L. taiwanensis，一种先前被描述的啮齿动物。L. taiwanensis对BALB/c小鼠的感染提高了调节性T细胞的频率，并导致更大的蠕虫建立，证明了肠道细菌促进肠道寄生虫感染的因果关系，并暗示细菌诱导的T细胞扩增是更大的蠕虫易感性的机制。宿主、细菌和寄生虫之间三方相互作用的发现对地方性人群中抗生素和驱虫剂的使用具有重要意义。
The intestinal microbiota are pivotal in determining the developmental, metabolic and immunological status of the mammalian host. However, the intestinal tract may also accommodate pathogenic organisms, including helminth parasites which are highly prevalent in most tropical countries. Both microbes and helminths must evade or manipulate the host immune system to reside in the intestinal environment, yet whether they influence each other’s persistence in the host remains unknown. We now show that abundance of Lactobacillus bacteria correlates positively with infection with the mouse intestinal nematode, Heligmosomoides polygyrus, as well as with heightened regulatory T cell (Treg) and Th17 responses. Moreover, H. polygyrus raises Lactobacillus species abundance in the duodenum of C57BL/6 mice, which are highly susceptible to H. polygyrus infection, but not in BALB/c mice, which are relatively resistant. Sequencing of samples at the bacterial gyrB locus identified the principal Lactobacillus species as L. taiwanensis, a previously characterized rodent commensal. Experimental administration of L. taiwanensis to BALB/c mice elevates regulatory T cell frequencies and results in greater helminth establishment, demonstrating a causal relationship in which commensal bacteria promote infection with an intestinal parasite and implicating a bacterially-induced expansion of Tregs as a mechanism of greater helminth susceptibility. The discovery of this tripartite interaction between host, bacteria and parasite has important implications for both antibiotic and anthelmintic use in endemic human populations.