Nipah virus (isolate UMMC1, Genebank AY029767) [49] was prepared on Vero-E6 cells as described previously [50] . HUVECs were infected with a multiplicity of infection (MOI) of 1 and harvested for RNA isolation 8 and 24 hours post infection (p.i.). At indicated times p.i. 150 ml of cell culture supernatant were collected and frozen and viral titration was performed as detailed elsewhere [50] .