Mycobacterium abscessus infection leads to enhanced production of type 1 interferon and NLRP3 inflammasome activation in murine macrophages via mitochondrial oxidative stress
Fig 6
MAB-R infection enhanced IFN-β production via the cGAS−STING axis in infected murine macrophages.
(A) RAW264.7 cells were transfected with siRNAs targeting cGAS or STING or a scramble siRNA (siNT). Forty-eight hours after transfection, protein and transcription levels were measured in total cell lysates by immunoblotting (left panels) and RT-qPCR (right panels), respectively. (B-D) RAW264.7 cells were transfected with cGAS, STING or a scramble siRNA (siNT). Forty-eight hours after transfection, the cells were infected with MAB-R or -S strains (10 M.O.I) and then harvested 24 h after infection. The transcription levels of IFN-β and IL-1β in infected cells were measured via qRT-PCR. Normalization was performed using the β-actin gene (B). IL-1β and IFN-β cytokine levels in the supernatant of infected cells were measured by ELISA (C), and infected cell lysates were serially diluted and plated onto 7H10 agar plates for CFU assays (D). Error bars represent the SD. Statistical significance was determined by ANOVA with Tukey's multiple comparison test (A) two-way ANOVA with multiple comparison test (B-D).