CYTOMEGALOVIRUS-RELATED AND INTERFERON-RELATED EFFECTS ON HUMAN ENDOTHELIAL-CELLS - CYTOMEGALOVIRUS-INFECTION REDUCES UP-REGULATION OF HLA CLASS-II ANTIGEN EXPRESSION AFTER TREATMENT WITH INTERFERON-GAMMA

Cultured human umbilical vein endothelial cells (HUVEs) were infected with human cytomegalovirus (HCMV) strain AD 169. Up to 5 0% HUVEs proved to be positive for HCMV early nuclear antigens 24 hours after inoculation with virus. Following infection kinetics of surface expression of HLA class I and II, intercellular adhesion molecule (ICAM-1) and endothelial lymphocyte adhesion molecule (ELAM-1) on HUVEs were investigated by means of flow cytometry. A slight increase in HLA class I expression was observed, whereas expression of HLA class II (DR, DP, DQ) antigens was not induced by infection with HCMV. Furthermore, when compared with uninfected cells treated with interferon-gamma (IFN-gamma), reduced enhancement of HLA-DR expression was conspicuous in HCMV-infected cells treated with IFN-gamma. There is evidence that only a portion of HUVE is affected in its ability to upregulate HLA class II antigens. While expression of ICAM-1 was found to be enhanced between 8 and 20 hours after infection with a maximum at 12 hours after infection, no modulation of ELAM-I was seen.