牛初乳中的IgG对肠黏膜免疫系统调节的初步研究

Regulatory Effects of IgG from Bovine Colostrum on Gastrointestinal Mucosa Immunity System

目的:探索牛初乳中的IgG对家兔胃肠黏膜免疫系统中细胞因子网络的调节作用。方法:以家兔为研究对象,通过口服,腹腔注射,耳静脉注射IgG这三种给药方式,分别在3、2、2h后取血,并用ELISA法检测血清中IFN-γ,TNF-α,TGF-β1,IL-1β,IL-10,IL-4,IL-6,IL-1Ra的水平。结果:口服IgG后发炎细胞因子IL-6,IL-1β,TNF-α,IFN-γ水平比给药前显著上升,抗炎细胞因子IL-1Ra、IL-4、IL-10及TGF-β1的水平比给药前显著下降;而腹腔注射和静脉注射IgG后,抗炎细胞因子水平升高,发炎细胞因子水平下降。结论:口服牛初乳中的IgG,IgG并不会被吸收,而是被肠上皮细胞、巨噬细胞、肥大细胞以及NK细胞等先天免疫细胞所识别,并最终促进发炎细胞因子的产生,抑制抗炎细胞因子的产生。相反,腹腔和静脉注射IgG,IgG会与免疫细胞的FcγRⅡB受体结合,从而抑制发炎细胞因子的产生,诱导抗炎细胞因子的产生。

Objective： To explore and evaluate the regulatory effects of IgG from bovine colostrum on cytokine network in gastrointestinal mucoca immunity systercL Methods： Rabbit serum was collected 3, 2, and 2 h after oral administration, intraperitoneal injection and ear intravenous injection with IGF- 1, respectively, to examine the contents of IFN-γ,TNF-α,TGF-β1,IL-1D,IL-10,IL-4,IL-6,and IL-1Ra by ELISA assay. Results： After oral administration, the contents of inflammatory cytokines like IFN- γ, 1I,-6, IL-1 and TNF- α were significantly increased while those of anti-inflammatory cytokines like TGF- β1, IL- 10, IL-4 and IL-1Ra were significantly decreased. The IgG administration by intraperitoneal injection or ear intravenous injection resulted in the content increases of the anti-inflammatory cytokines and the content decrease of the inflammatory cytokines. Conclusions： IgG which is administered orally can not be absorbed but identified easily by intestinal epithelial cells, macrophages, mast cells, NK cells and other innate immune cells and thus induces the production of inflammatory cytokines and inhibits the production of anti-inflammatory cytokines. In contrast, IgG administered in the ways of intraperitoneal injection and intravenous injection is easy to bind with the inhibitory Fcγ RⅡB of immune cells so as to inhibit the production of inflammatory cytokines and induce the production of anti-inflammatory cytokines.