MCL Plays an Anti-Inflammatory Role in Mycobacterium tuberculosis-Induced Immune Response by Inhibiting NF-κB and NLRP3 Inflammasome Activation

Figure 4

MCL attenuates the amount of NLRP3 inflammasome components in Mtb-infected Raw264.7 cell. Raw264.7 cells (1 × 10⁵/well) were seeded in 6-well plates which were precovered with cell climbing slice overnight, and the cells were infected with H37Ra as previously. Cells were then treated with MCL at the concentration of 10 μM for 12 hr. Rabbit anti-ASC (green) or rabbit anti-caspase-1 (green) antibody and DAPI (blue) were used for immunostaining assay. Images were taken with laser scanning confocal microscopy. Con. is the abbreviation of control group, which showed no effect on the expression of ASC (a) and caspase-1 (b). Mtb promoted the formation and amounts of ASC specks, and the treatment of MCL reduced it apparently (a). Meanwhile, consistent with ASC, Mtb infection evidently augments the expression of caspase-1 and MCL decreased caspase-1 (b). Thus, MCL treatment apparently inhibits the activity of NLRP3 inflammasome. The results of (a) and (b) were obtained, respectively.

(a)

(b)