화학공학소재연구정보센터
Current Microbiology, Vol.76, No.4, 510-519, 2019
Deletion of the Type IV Secretion System Effector VceA Promotes Autophagy and Inhibits Apoptosis in Brucella-Infected Human Trophoblast Cells
Brucellosis is the most common zoonotic disease that caused by intracellular parasitic bacteria Brucella. The survival and replication of Brucella in the host depend on the type IV secretion system (T4SS). The T4SS system of Brucella has many components and secreted proteins. But the mechanism helped Brucella to evade the host defense is still not clear. The objective of the present study was to investigate the effects of VceA on autophagy and apoptosis in Brucella-infected embryonic trophoblast cells. We constructed the VceA mutant strain (2308VceA) and complementary strain (2308VceA-C) of Brucella abortus 2308 (S2308). The human trophoblast cells (HPT-8 cells) and mice were infected by S2308, 2308VceA and 2308VceA-C. The cell autophagy and apoptosis were detected. The Atg5, LC3-II and Bcl-2 mRNA expression were significantly increased in 2308VceA group than the S2308 group, and mRNA expression of P62 and Caspase-3 were significantly decreased than the S2308 group. Western blotting, qPCR and flow cytometry analysis showed that 2308VceA promoted autophagy and inhibited apoptosis. Mouse immunohistochemistry experiments showed that P62 protein was scattered coloring and Cytochrome C protein was scarcely in 2308VceA group at the myometrium. These results indicated that 2308VceA promoted autophagy and inhibited apoptosis in HPT-8 cells during Brucella infection.