Figure 5

Thermal stability and virus-like particles (VLP) formation. The four H5N6 viruses were incubated at 56℃ for 5, 10, 15, 30, 60, 90, 120, 150 and 180 min. A Mean HA titers of the four H5N6 viruses were tested by haemagglutination assay. B TCID₅₀ titers of the four H5N6 viruses were determined in MDCK cells. C The supernatants were collected to purify the VLP by sucrose density gradient centrifugation at 48 h, and the hemagglutination test was employed to detect the aboundance of VLP. D The HA protein levels were measured in supernatants by western blotting. The values represent means ± SD from three independent experiments (*P < 0.05, ***p < 0.001).