口服耐受机制的研究进展

Mechanism of oral tolerance

口服耐受是指机体口服某种抗原后,表现出特异性无应答或低应答的状态,但机体对其他抗原仍可产生正常的免疫应答。当口服耐受未能正常建立或被破坏时,机体就可能发生过敏反应。近年来,我国儿童食物过敏发病率增高,家长报告率平均为5.83%,因此研究口服耐受的建立机制具有极其重要的意义。口服耐受的机制有主动抑制、旁路抑制、克隆清除和免疫无能。口服低剂量抗原可诱导调节性T细胞分泌抑制性细胞因子,主动地抑制效应T细胞的功能;口服大剂量抗原后,机体会出现克隆清除或免疫无能的现象。调节性B细胞、树突状细胞、各种细胞因子、肠道菌群及其代谢产物等也在口服耐受中扮演着重要的角色。该文就口服耐受的机制及部分影响因素作一综述。

Oral tolerance is a state of no or low response to a specific oral antigen,but there are still normal immune responses to other antigens.Anaphylaxis may occur when oral tolerance is not established or destroyed.In recent years,the incidence of food allergy in Chinese children has increased,with an average of 5.83%reported by parents.Therefore,it is of great significance to explore the mechanisms of oral tolerance.The mechanisms of oral tolerance include active suppression,bypass suppression,clonal anergy/deletion.Oral administration of low-dose antigen can induce regulatory T cells to secrete inhibitory cytokines and actively inhibit effector T cells.Oral administration of high-dose antigen can induce clonal anergy/deletion.Regulatory B cells,dendritic cells,various cytokines,gut microbiota and short-chain fatty acids also play an important role in oral tolerance.This review focuses on the mechanism and some influencing factors of oral tolerance.