Objective: To determine the tumor necrosis factor (TNF) receptor type involved in induction of E-selectin expression on vascular endothelial cells.
Design: Prospective, in vitro repeated-measures analysis of cellular responses.
Setting: Research laboratory in an academic medical center.
Subjects: Cultured human umbilical vein endothelial cells.
Interventions: Human umbilical vein endothelial cells were incubated with recombinant human TNF (rhTNF) to induce the expression of E-selectin on their surfaces. To block rhTNF from binding to receptors, the cells were incubated with monoclonal antibodies against TNF receptors (anti-CD120a and anti-CD120b). TNF-induced E-selectin expression of the endothelial cells, with and without blocking antibodies, was then determined using indirect immunofluorescence and flow cytometry.
Measurements and main results: Blocking of either CD120a or CD120b receptors individually resulted in inhibition of TNF-induced E-selectin expression on human umbilical vein endothelial cells. When both antibodies were added, the inhibition of TNF-induced E-selectin expression was synergistic. Inhibition of E-selectin expression was dependent on both TNF concentrations and antibody concentrations.
Conclusions: Both CD120a and CD120b receptors are involved in TNF-induced E-selectin expression on human umbilical vein endothelial cells. Blocking of both or one receptor type can reduce or totally inhibit expression of E-selectin on human umbilical vein endothelial cells, but the response is dependent on both TNF and antibody concentrations.