A-F Primary human umbilical vein endothelial cells (HUVECs) or primary human dermal microvascular endothelial cells (HMVEC-DBls) were stimulated at 80% confluency with Vasculotide (treatment), Ang1 (positive control; ligand of Tie2), PBS (vehicle control), or VEGF (negative control; non-ligand of Tie2). Tie2 was immunoprecipitated from cell lysates and immunoblotted for total Tie2 or phosphotyrosine. Vasculotide treatment did not lead to increases in the pTie2/Tie2 ratio in HUVECs after 45-min (A-D) or 15-min (E) treatments, with (E) or without (A-D) serum/supplement starvation. Vasculotide also did not activate Tie2 receptors in HMVEC-DBls, whether in the presence or absence of serum, growth factor, and cytokine supplements (F). 