The Interacrion Between Mycobacterium Tuberculosis And Autophagy In Alveolar Epithelial Cell Type â…¡

Mycobacterium tuberculosis (M.tuberculosis) commonly known as TB, is caused by TB bacteria. A large number of studies over the last concern of Mycobacterium tuberculosis with macrophages relationship between. Recently, people began to realize that alveolar epithelial cells infected with Mycobacterium tuberculosis play an important role. Mycobacterium tuberculosis can not only invade into epithelial cells, and can replicate in alveolar epithelial cells.Alveolar type II epithelial cells are a group of multi-functional cell lung protection. While under the influence of Mycobacterium tuberculosis, alveolar type II epithelial cells can secrete a large number of gama-IFN, which in the natural immunity play an important role. Recent studies have shown that alveolar type II epithelial cells sterilization.In this study, RT-PCR method, total RNA from A549 cells was amplified cDNA sequence encoding human LC3 molecules by MTB infection in alveolar type II epithelial cells A549 after the detection of LC3 mRNA expression changes, and to investigate the 3 - methyl adenine (3-methyladenine ,3-MA) on the inhibition of LC3. To further verify the accuracy of this experiment, application of RNA interference expression was constructed by the low autophagic cell lines, further experiments show that autophagy in type II alveolar epithelial cells resistant Mycobacterium tuberculosis play an important role in the process of . This study further autophagy and Mycobacterium tuberculosis infection, of Mycobacterium tuberculosis molecular mechanisms of disease basis.To study the role of autophagy in the resistance of Mycobacterium tuberculosis in the process, especially in this experiment was designed RNAi sequences against Atg5 sequence and import it into the expression vector pSilencer ? 3.1-H1 hygro, after sequencing, the sequence is correct. And then sequencing the plasmid transfected A549 cells transfected with the Western Blot test results, results showed that the inhibitory effect of good genes. After using the cell model to further verify the autophagosome in Mycobacterium tuberculosis Infection. The results show that interference by RNAi technology Atg5 gene, autophagosome lower expression levels of LC3â…¡. BCG infection at a time then A549 cells, resistance decreased. It showed the autophagosome in alveolar typeâ…¡cells resistant Mycobacterium tuberculosis plays an important role.This study shows that autophagy play a key role in type II alveolar epithelial cells infected with Mycobacterium tuberculosis , and Mycobacterium tuberculosis can inhibit autophagy, autophagy of the alveolar type II epithelial cells inhibited by 3MA, Mycobacterium tuberculosis resistance decreased. Construction of the low expression of autophagy by the cell line A549, further confirmed the low expression of autophagy in the cells by Western Blot, Mycobacterium tuberculosis resistance decreased significantly. In summary, the infection of Mycobacterium tuberculosis in epithelial cells in the process of autophagy is a protective mechanism. If autophagy is inhibited, cells of Mycobacterium tuberculosis resistance to drop, and necrosis of the epithelial cells help the spread of Mycobacterium tuberculosis after infetion.