Infection-Induced Vascular Permeability Aids Mycobacterial Growth

Pathogenic mycobacteria trigger formation of organized granulomas. As granulomas mature, they induce angiogenesis and vascular permeability. Here, in a striking parallel to tumor pro-angiogenic signaling, we identify angiopoietin-2 (ANG-2) induction as an important component of vascular dysfunction during mycobacterial infection. Mycobacterial infection in humans and zebrafish results in robust induction of ANG-2 expression from macrophages and stromal cells. Using a small-molecule inhibitor closely related to one currently in clinical trials, we link ANG-2/TIE2 signaling to vascular permeability during mycobacterial infection. Targeting granuloma-induced vascular permeability via vascular endothelial-protein tyrosine phosphatase inhibition limits mycobacterial growth, suggesting a new strategy for host-directed therapies against tuberculosis.