Probiotics and functional foods in immunosupressed host

Abstract

The intestine is colonized by several bacterial species comprising the normal microbiota.It is known that exist an active dialogue between the commensal microorganisms and the intestinal epithelial and immune cells. This crosstalk can produce different responses of the gut immune system in order to maintain the homeostasis. Daily food intake harbors many microorganisms that can influence positively or negatively this balance. Among the beneficial microorganisms we can mention probiotics, many of which are contained in fermented products. One of the main properties attributed to probiotics is the improvement of the host immune states. It was demonstrated that probiotic fermented milk administration activated mainly the innate immune response, and promoted immunity at sites outside the gut such as bronchus and mammary glands. Experimental animal models are useful to understand the mechanisms implicated in the probiotic interaction with intestinal epithelial and immune cells. This chapter deals with the stimulation of the intestinal and systemic immune responses affected by malnutrition or stress using animal models. Probiotic bacteria or a probiotic fermented milk successfully restored the compromised immune system.