Crosstalk between Gut Microbiota and Host Mucosal Immune System

Abstract

The research on intestinal microbiota has recently accelerated and expanded with the development of the sequencing and mass spectrometric technologies such as metagenomic and metabolomic analyses. As the research on the elucidation of crosstalk between intestinal microbiota and mucosal immune system progresses, it has become clear that the immune effector molecules such as secretory IgA (SIgA) antibodies have important roles in the creation and maintenance of the unique homeostasis between intestinal microbiota and host intestinal tissues via so called physiological inflammation. To this end, T helper cell subsets with an opposite regulatory functions of activation and inhibition are induced and maintained by intestinal microbiota for the development of physiological inflammatory state in the intestine. This physiological inflammation is tightly controlled by the crosstalk between intestinal microbiota and mucosal immune systems, thereby disruption of this homeostasis leads to the onset of immune diseases including inflammatory bowel disease. Further studies about the molecular and cellular mechanisms of the homeostasis of intestinal microflora and the mucosal immune system should provide the important basic information for the development of the innovative treatment of these undesired diseases as well as contribute to the developmental strategy of mucosal vaccine such as oral vaccine as a new generation vaccine for the control of emerging and re-emerging infectious diseases.