Inhibition of soluble tie-1 release by the hydroxamic acid-based metalloprotease inhibitor BB-24. HUVECs were preincubated with the indicated concentrations of BB-24 for 15 minutes before the stimulation of tie-1 release by (A) 10 ng/mL TNF (•) or (B) 10 ng/mL PMA (▪), 100 ng/mL VEGF (•), 10 ng/mL IL-1β (▴), or 10 ng/mL LPS+100 ng/mL soluble CD14 (⧫). After 1 hour of incubation, supernatants were collected and analyzed for soluble tie-1 release by sandwich ELISA as described in Materials and Methods. Basal soluble tie-1 release in the presence of media alone (○) was also inhibited by BB-24. Results are expressed as the percentage control (±SD), where 100% control represents soluble tie released by HUVECs in the absence of inhibitor.