MEMORY T-LYMPHOCYTES ADHERENCE TO INTERFERON GAMMA-ACTIVATED HUMAN DERMAL MICROVASCULAR ENDOTHELIAL-CELLS VIA E-SELECTIN

The regulation of leukocytes-endothelial cells binding by biological response modifiers have an important role in determining the progression of acute and chronic inflammatory responses. In order to define the influence of E-selectin on the binding of T lymphocytes to human dermal microvascular endothelial cells (HDMEC), we examined the cell surface expression of E-selectin on HDMEC and the regulation of the binding of T lymphocytes to HDMEC by IFN-gamma. We have demonstrated that stimulation of HDMEC with IL-1 alpha or TNF alpha leads to transient E-selectin induction which disappears after 48 h, but stimulation of HDMEC with IFN-gamma resulted in delayed E-selectin induction which was seen at 48 h of incubation and persisted until 72 h after stimulation, However, stimulation with IFN-gamma failed to induce E-selectin expression on human umbilical vein endothelial cells. The delayed E-selectin expression on HDMEC by IFN-gamma coincided with the increases in T lymphocyte binding to IFN-gamma-activated HDMEC. The binding of memory T lymphocytes to IFN-gamma-activated HDMEC was greater than that of naive T lymphocytes. Anti-E-selectin antibody partially inhibited memory T lymphocyte binding to HDMEC after 48 h of stimulation with IFN-gamma. These data show that E-selectin expressions by IFN-gamma on endothelial cells are regulated in a tissue-specific fashion and that E-selectin may be important in vivo in the preferential migration of memory T lymphocytes into inflammatory sites in the skin.