Figure 2.

Proposed cell-to-cell spread model for M. tuberculosis during host cell infection. Internalized M. tuberculosis disrupts phagosome in an ESAT-6 dependent manner. After reaching the cytosol, mycobacteria trigger ER stress, and activate pro-apoptotic cellular routes involving the ASK1-p38MAPK signaling axis, and causing host cell apoptosis by activation of the mitochondrial apoptotic pathway. Consequently, fresh macrophages are recruited and M. tuberculosis-containing apoptotic bodies are phagocytosed by new cells, re-starting the infection cycle.