(A) Raw 264.7 cells were infected with Mtb H37Ra at a multiplicity of infection (MOI) of 1 or 10 and then incubated for the indicated times. Western blot analysis of CRT expression. (B) THP-1 cells were incubated with Mtb H37Ra (MOI=10) for the indicated times. Western blot analysis of CRT expression. (C) Raw 264.7 cells were infected with Mtb H37Ra (MOI=10) and then incubated for the indicated times. The levels of CRT, GRP78, p-eIF2α, CHOP, caspase-3, and β-actin determined by western blotting. (D-G) Raw 264.7 cells were pretreated with specific inhibitors for 1 h and then infected with Mtb H37Ra (MOI=10) for 24 h. CRT production was analyzed by western blotting in the absence or presence of (D) GSK2606414 (3 μM), (E) irestatin (5 μM), or (F) AEBSF (500 nM) for 24 h. (G) Flow cytometric analysis of the cell-surface expression of CRT in the absence or presence of ER-stress-specific inhibitors at 24 h post-infection. Western blot data presented are representative of three independent experiments. Numbers below the blot indicate the intensities ratios of each target protein to the β-actin control in each lane. Thapsigargin (TG; 500 nM) and Staurosporine (STS; 500 nM, 18 h) served as the positive control. The data are means ± SD of three independent experiments. ***p<0.001.