FIG 3.

Autophagy-dependent induction of TNF-α. (A) Peritoneal macrophages derived from TLR2 KO mice were treated with 100 μM chloroquine or 5 mM 3MA for 30 min. The treated cells were infected with live M. pneumoniae. After 6 h of incubation, TNF-α concentrations in the culture medium were measured using ELISA. (B and C) Peritoneal macrophages were infected with live M. pneumoniae for 6 h. LC3 was stained with anti-LC3 antibody and FITC-labeled secondary antibody (green). DNAs of macrophages and M. pneumoniae were stained with DAPI (blue). Small DNA particles derived from M. pneumoniae are indicated with arrows. Bar, 20 μm. (D) Peritoneal macrophages derived from TLR2 KO mice were treated with 2 μM cytochalasin D for 30 min and then infected with M. pneumoniae. After 6 h of incubation, TNF-α concentrations in the culture medium were measured using ELISA. All values are presented as the means and SD of the results of 3 assays. *, P < 0.01 compared with PBS or DMSO treatment by multiple comparison.