Virus induced adherence of monocytes to endothelial cells

In this study we have demonstrated that infection of human umbilical vein endothelial cells (HUVEC) with Herpes simplex virus type 1 (HSV-1) resulted in an increased adherence of monocytes (MC). This enhanced adherence occurred at 3 h post infection (p.i.) when about 20% of the monolayer is infected and when there is no cytopathic effect observable in the monolayer. The adherence of human MC to virus-infected HUVEC monolayers proved to be effective and reproducible if a multiplicity of infection (MOI) of ten and a ratio of number of MC to number of HUVEC of 5 was used. The increased adherence was also induced by incubating non-infected HUVEC with the 'supernatant medium' of the HSV-1 infected cells, showing that soluble factors induced by viral infection are responsible for the increased adherence. The augmentation of MC adherence to infected endothelium was sensitive to tunicamycin treatment, suggesting that the MC adherence is probably mediated by glycoproteins expressed on the HUVEC membranes by virus infection.