Digibind attenuates cytokine TNFα-induced endothelial inflammatory response: potential benefit role of Digibind in preeclampsia

Objective: Exaggerated inflammatory response occurs in preeclampsia. Preeclampsia is also associated with elevated endogenous digoxin-like factors (EDLFs). Clinical data suggest that Digibind (a polyclonal sheep digoxin binding Fab fragment) binds to EDLF and may have the potential to attenuate vasoconstriction and other clinical symptoms of preeclampsia. This study was undertaken to determine if Digibind could attenuate increased endothelial inflammatory response induced by tumor necrosis factor-α (TNFα). Study Design: Confluent endothelial cells were treated with TNFα at different concentrations with or without Digibind in culture. Endothelial adhesion molecule ICAM, VCAM and E-selectin expressions were determined by an immunoassay directly detected on the endothelial surface. Effects of Digibind on TNFα-induced extracellular signal-regulated kinase and Na + /K + -ATPase expressions were also examined. Result: (1) TNFα induced dose-dependent increases in ICAM, VCAM and E-selectin expressions in endothelial cells; (2) Digibind could attenuate and reduce TNFα-induced upregulation of endothelial E-selectin, ICAM and VCAM expressions. The blocking effect was in a concentration dependent manner; (3) Digibind had no effects on TNFα-induced upregulation of extracellular signal-regulated kinase phosphorylation, but could block TNFα-induced downregulation of Na + /K + -ATPase β1 expression. Conclusion: Digibind may exert beneficial effects by preserving cell membrane Na + /K + -ATPase function and consequently to offset increased inflammatory response in endothelial cells.