Current Knowledge on Intestinal Microbes and Immunity

Abstract

The aggregation of many microorganisms, ranging from virus, bacteria, parasites, to lower plants such as fungi are frequently referred to as the microbiota, colonizes the skin and mucosal surfaces of vertebrates. In man, more than 100 trillion microorganisms, mostly bacteria, colonize the oral-gastrointestinal tract, and the majority of these microbes dwell in the distal digestive tract. A large number of years of co-evolution between the host and microorganisms have prompted a mutualistic relationship in which the micro-biota adds to many host physiological processes and, thus, the host gives niches and supplements to microbial survival. The principal roles of the microbiota to the host incorporate the digestion and fermentation of sugars, the synthesis of vitamins, the improvement of gut-related lymphoid tissues (GALTs), the polarization of gut-specific insusceptible reactions and the aversion of colonization by pathogens. Thus, gut resistant reactions that are initiated by commensal populaces control the creation of the microbiota. Therefore, an overwhelming interchange between the host immune system and the microbiota is fundamental for gut homeostasis. Nevertheless, when the mutualistic relationship between the host and microbiota is disturbed, the gut microbiota can initiate or add to infection. In this review, we will be discussing on both the beneficial and detrimental roles of the gut microbiota.