Role of lncRNA-mtb in Mycobacterium tuberculosis-infected macrophages

Objective To study the mechanism of lncRNA-mtb in Mycobacterium tuberculosis (M.tuberculosis)-infected macrophages. Methods A predicting software and Western blot assay were used to verify the non-coding nature of lncRNA-mtb. RT-qPCR was performed to detect lncRNA-mtb expression in macrophages infected by different Mycobacteria. Cytokine secretion was detected with ELISA after silencing the expression of lncRNA-mtb in macrophages with RNA interference (RNAi) technology. Western blot and RT-qPCR were performed to analyze whether the activation of macrophage inflammation could be induced by lncRNA-mtb during M. tuberculosis infection. Effects of lncRNA-mtb silencing on the bactericidal activity of M. tuberculosis-infected macrophages were evaluated. Results Increased expression of lncRNA-mtb was observed in macrophages infected with M. tuberculosis H37Rv or H37Ra. After silencing the expression of lncRNA-mtb, IL-1β secretion in H37Rv infected-macrophages was significantly decreased. Further studies revealed that lncRNA-mtb might be involved in the activation of NLRP3 in M. tuberculosis-infected macrophages. The bactericidal activity of macrophages against H37Ra was impaired after silencing the expression of lncRNA-mtb. Conclusions Enhanced expression of lncRNA-mtb could be induced in macrophages infected with H37Rv or H37Ra. Moreover, lncRNA-mtb was involved in M. tuberculosis-induced inflammation in cells. Silencing lncRNA-mtb wolud attenuate the ability of macrophages to clear M. tuberculosis. Key words: Mycobacterium tuberculosis; lncRNA-mtb; Macrophage; Inflammation