Author(s)

Qingfeng Wan, Tingyu Wu, Man Ma

Corresponding Author

Qingfeng Wan

ABSTRACT

There are hundreds of millions of microorganisms in the intestinal tract of animals. These symbiotic microorganisms can help the animals digest and metabolize and maintain intestinal homeostasis. However, microorganisms and their metabolites can also act as antigens to affect the normal function of the intestine. Under normal circumstances, the intestinal immune system can accurately identify symbiotic microorganisms and their metabolites, make them immune tolerant, and maintain homeostasis; in addition, the immune system of the intestine can also avoid the reaction to harmless antigens, and the waste of immune resources. Immune tolerance has been widely used in clinical medicine to reduce the incidence of rejection after organ transplantation and reduce the immune rejection of the uterus to the fetus. However, there are still few reports on how to use the immune tolerance mechanism to slow the ruminal acidosis in ruminants, increase the efficiency of synthesis and utilization of rumen microbial proteins, and improve the feeding regulations for probiotics. To this end, this paper describes the general concepts and applications of immune tolerance, the composition and function of the intestinal immune system, the immunogenicity of intestinal commensal microorganisms, and the mechanism of intestinal immune tolerance.

KEYWORDS

Immunity system, intestinal symbiotic microorganisms