Cell viability assay
To determine the effect of H9N2 virus on cell death,HUVECs were infected with the viruses at a MOI of 5,and cell viability was determined at selected time intervals by the trypan blue-exclusion assay. At 24 h postinfection,there were approximately 62% viable cells, which decreased to 43% at 36 h postinfection.For mock-infected cells,the number of viable cells remained relatively constant throughout the experiment.Our data demonstrated that
H9N2 viral infection caused an apparent decrease in viability of
HUVECs. This drop in cell viability might be related with reduction
in viral titers at the late stage of H9N2 virus infection of HUVECs.