Study on Brucella interfering the ubiquitin-dependent autophagic pathway in macrophage / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the effect on ubiquitin-dependent autophagic pathway in macrophage(MΦ) infected by B.suis S1330 attenuated strains.Methods Infected MΦ in vitro using Brucella S1330 strains to construct experimental model.Observed the process of phagocytic,the level of ubiquitination and autophagy in MΦ of mice.MΦ was divided into control group,infected group,positive control group and infected group after RAPA induced autophagy.The Giemsa staining immunofluorescence and Western blot were applied to observe the chances of ubiquitinated and autophagic protein in MΦ at different time points within different groups.Results Ubiquitinated bacterial protein was detected at 0.5 h after infected MΦ.With the time passing,the ubiquitinated bacterial protein increased and aggregated intracellular until MΦ dead at 12 h after infected.The expression of LC3B protein was serious deficiency in MΦ which infected group,but ubiquitinated bacterial protein decreased significantly in MΦ after RAPA induced.Conclusion Brucella S1330 stain can arouse intracellular ubiquitination process in infected MΦ,and interfere the ubiquitin-dependent autophagic pathway.A large number of aggregated and ubiquitinated bacterial protein can not be effectively removed,it leads to MΦ dysfunction and dead.