Anti-TNF antibody partially suppresses rhHMGB1-mediated endothelial cell activation.

Polyclonal neutralizing anti-TNF antibody (5 and 10 μg/mL) was incubated with HMEC-1, 30 minutes prior to stimulation with rhHMGB1 (100 ng/mL), TNFα (10 ng/mL), or media alone. (A) Anti-TNF antibody (10 μg/mL) treatment suppressed TNFα-induced IL-8 release by 91% ± 0.2% and rhHMGB1 IL-8 release by 72% ± 2 (P = .004). Suppression of the TNFα-induced production of IL-8 was greater than that of rhHMGB1 (P = .002). The antibody did not completely suppress the effects of either stimulus (TNFα with anti-TNF versus media alone or rhHMGB1 with anti-TNF versus media alone, P = .003). Similar responses were observed for ICAM-1 (B) and VCAM-1 (C) expression with 5 and 10 μg/mL anti-TNF antibody (P < .002). Data represent mean ± SEM of 3 separate experiments.