Expression of cell surface markers on HMEC-1 over 48 hours following incubation with rhHMGB1 (50 ng/mL), TNFα (10 ng/mL), or media alone.

Significantly different time courses were observed for (A) ICAM-1 (P = .002), (B) VCAM-1 (P = .01), and (C) RAGE (P = .03) under the 3 conditions. Increased expression of ICAM-1 and VCAM-1 occurred within 3 hours after TNFα stimulation and was delayed until 6 hours after rhHMGB1 stimulation. Increased expression of RAGE occurred within 1 hour after either TNFα or rhHMGB1 stimulation and followed a similar time course. Data represent mean ± SEM of 4 separate experiments.