AngTie2

AngTie2 refers to the angiopoietin-2 (ANGPT2) ligand and its signaling axis with the endothelial receptor tyrosine kinase Tie2 (also known as TEK). The ANG-Tie signaling pathway regulates endothelial cell function, vascular stability, and remodeling during development and in response to physiological and pathological cues.

ANGPT2 is a secreted protein produced by endothelial cells that binds the Tie2 receptor on the surface of endothelial cells. Its activity is context dependent: in many settings it antagonizes ANGPT1-Tie2 signaling, promoting destabilization of existing vessels and increasing vascular permeability; in the presence of vascular endothelial growth factor (VEGF), ANGPT2 can facilitate angiogenic sprouting and new vessel formation.

AngTie2 plays roles in embryonic development, tissue repair, and adaptive remodeling of the vasculature. It interacts with other signaling pathways to influence vascular maturation, permeability, and inflammation. The balance between ANGPT2 and ANGPT1 signaling influences whether vessels remain stable or become remodeled, leaky, or sprouting.

Dysregulation of ANGPT2 has been associated with several diseases. Elevated ANGPT2 levels are observed in conditions such as sepsis, acute lung injury and acute respiratory distress syndrome (ARDS), certain cancers, and preeclampsia, where increased vascular permeability and endothelial dysfunction are common features. ANGPT2 is studied as a potential biomarker for endothelial dysfunction and as a therapeutic target; approaches include ANGPT2-neutralizing strategies and efforts to modulate Tie2 signaling to promote vascular stabilization.