Sutherland Duncan B, Suzuki Keiichiro, Fagarasan Sidonia
Laboratory of Intestinal Immunology, Global Health Institute, School of Life Sciences, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland.
Center for Innovation in Immunoregulative Technology and Therapeutics, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Immunol Rev. 2016 Mar;270(1):20-31. doi: 10.1111/imr.12384.
Immunoglobulin A (IgA), the most abundantly secreted antibody isotype in mammals, not only provides direct immune protection to neonates via maternal milk but also helps program the infant immune system by regulating the microbiota. IgA continues to maintain dynamic interactions with the gut microbiota throughout life and this influences immune system homeostasis as well as other physiological processes. The secretory IgA produced independently of T-cell selection are commonly referred to as natural or innate antibodies. Our studies have shown that innate-IgA, while effective at excluding microorganisms from the gut, does not promote mutualism with the microbiota in the same way as adaptive-IgA that is selected in T cell-dependent germinal center reactions. Adaptive-IgA fosters more advanced mutualism with the microbiota than innate-IgA by selecting and diversifying beneficial microbial communities. In this review, we suggest that the diversified microbiota resulting from adaptive-IgA pressure was pivotal in promoting ecological adaptability and speciation potential of mammals.
免疫球蛋白A（IgA）是哺乳动物中分泌量最丰富的抗体同种型，它不仅通过母乳为新生儿提供直接的免疫保护，还通过调节微生物群来帮助塑造婴儿的免疫系统。IgA在一生中持续与肠道微生物群保持动态相互作用，这会影响免疫系统的稳态以及其他生理过程。独立于T细胞选择产生的分泌型IgA通常被称为天然或固有抗体。我们的研究表明，固有IgA虽然能有效地将微生物排除在肠道之外，但与在T细胞依赖性生发中心反应中选择产生的适应性IgA不同，它不会以同样的方式促进与微生物群的共生关系。适应性IgA通过选择和使有益微生物群落多样化，比固有IgA更能促进与微生物群的高级共生关系。在这篇综述中，我们认为由适应性IgA压力导致的多样化微生物群在促进哺乳动物的生态适应性和物种形成潜力方面起着关键作用。
