Detection of Fcγ receptors on human endothelial cells stimulated with cytokines tumour necrosis factor‐alpha (TNF‐α) and interferon‐gamma (IFN‐γ)

This investigation was conducted to detect Fcγ receptors (FcγR) on cytokine‐stimulated human endothelial cells (EC) by measuring anti‐FcγR MoAb binding with an ELISA. TNF‐α and IFN‐γ significantly increased the expression of FcγR type II (FcγRII) and type III (FcγRIII) on aortic EC. Simultaneous treatment with both cytokines had a synergistic effect and pretreatment of EC with IFN‐γ augmented the effect of TNF‐α. The greatest effect was the increase (up to four‐to‐six‐fold) in expression of FcγRII found by the simultaneous treatment of aortic EC with both cytokines. The receptors were expressed on the cell surface and showed receptor capping after incubation at 37°C. This study showed that the inflammatory cytokines TNF‐α and IFN‐γ enhanced low‐affinity FcγR expression on human EC in vitro. The expression of FcγR may contribute to the specific localization of circulating immune complexes on blood vessels in areas of vasculitis.