Regulation of immune response at intestinal and peripheral sites by probiotics

Abstract

The gut associated lymphoid tissue (GALT) should protect intestinal mucosa against pathogens, but also avoid hypersensitivity reactions to food proteins, normal bacterial flora and other environmental macromolecules. The interaction between epithelial cells and microflora is fundamental to establish gut mucosal barrier and GALT development. The normal colonization of intestine by commensal bacteria is thus crucial for a correct development of mucosal immune system. Probiotic bacteria are normal inhabitants of microflora and may confer health benefits to the host. The modification of the intestinal microflora towards a healthier probiotics enriched microflora may generate beneficial mucosal immunomodulatory effects and may represent a new strategy to cure intestinal and allergic diseases. The health benefits may be specific for different probiotic strains. Ongoing research is providing new insights into the probiotic beneficial effects and related mechanisms. This review represents an update of immunomodulatory activity of different probiotics and of the more accredited mechanisms underlying such activities.