The crosstalk between bacteria and host autophagy: host defense or bacteria offense.

Xenophagy is a specific selective autophagy for the elimination of intracellular bacteria. Current evidence suggests that the processes for host autophagy system to recognize and eliminate invading bacteria are complex, and vary according to different pathogens. Although both ubiquitin-dependent and ubiquitin-independent autophagy exist in host to defense invading bacteria, successful pathogens have evolved diverse strategies to escape from or paralyze host autophagy system. In this review, we discuss the mechanisms of host autophagy system to recognize and eliminate intracellular pathogens and the mechanisms of different pathogens to escape from or paralyze host autophagy system, with a particular focus on the most extensively studied bacteria.