Cholera Toxin Suppresses Expression of Ubiquitin Editing Enzyme A20 and Enhances Transcytosis

Cellular Physiology and Biochemistry

关键词: Intestine;    Barrier function;    Ubiquitin editing enzyme A20;    Protein degradation;    Epithelial cells;   

DOI  :  10.1159/000350070

学科分类：分子生物学，细胞生物学和基因

来源: S Karger AG

【 摘 要 】

Background The ubiquitin editing enzyme A20 plays an important role in maintaining the homeostasis in the body Microbe-derived adjuvants are commonly used in animal models of intestinal allergy. Objective This study aims to investigate the role of cholera toxin-induced A20 suppression in compromising intestinal barrier function. Methods Human intestinal epithelial cells were cultured into monolayers as an in vitro epithelial barrier model. Ovalbumin (OVA) was used as a specific allergen to test the degrading capability of intestinal epithelial cells for the endocytic allergens. The fusion of endosomes and lysosomes in epithelial cells was observed by immunocytochemistry. The antigenicity of OVA was tested by T cell proliferation assay. Results A20 was detectable in the intestinal cell lines and mouse intestinal epithelialum. A20 was required in the degradation of endocytic allergens in HT-29 cells. The allergen, OVA, could pass through A20-deficient HT-29 monolayer barrier. Exposure to microbial adjuvant, cholera toxin, suppressed the expression of A20 in HT-29 cells, which compromised the epithelial barrier function. Conclusion The microbial product, cholera toxin, interferes with the expression of A20 in intestinal epithelial cells, which compromises the intestinal epithelial barrier function.

【 授权许可】

CC BY-NC-ND