FIG 7.

Proposed model of action for PPE51 inhibition of TLR2 signaling and autophagy. Data presented in the current study demonstrated that PPE51 inhibits TLR2-associated phagocytosis of Mtb and the associated signaling cascade. Infection of macrophages with Δ51 demonstrated increased phosphorylation of MAP kinase, ERK1/2 resulting in enhanced proinflammatory cytokine secretion, ROS accumulation, and autophagy. Pam₃CSK₄ competitively overcame the PPE51 inhibition of this signaling cascade, resulting in bactericidal autophagy during Mtb infection. The image was generated using BioRender.com.