Figure 6.

IFN-γ increases necrosis heavily infected macrophages as determined by loss of ΔΨ_m A) increased LDH release B) and increased HMGB1 release C) from heavily infected macrophages. A) Cells infected with Mtb Erdman at MOI of 25 for 3 h were stained with MitoTracker CMXRos to measure ΔΨ_m. The filled peak corresponds to uninfected cells, the solid line corresponds to Mtb-infected cells, while the dashed and dotted lines correspond to Mtb-infected cells treated with IFN-γ or IFN-γ plus Z-VAD-fmk, respectively. Histograms are representative of three independent experiments. B) For LDH assays IFN-γ pretreated BMDM were infected with BCG at MOI of 25 for 9 h and then supernatant was collected for measurement of LDH. Data are means ± SEM of four independent experiments. C) For HMGB1 assays cells were infected with Mtb Erdman at MOI of 25 for 6 h. Culture supernatants were collected and HMGB1 was measured by antigen-capture ELISA. Data are presented as the mean ± SD from two independent experiments. *p < 0.05.