Figure 2

Weight loss and replication of viruses in mice lungs (A, B); Neuraminidase activities and release efficiency of erythrocyte bound virions (C, D). A Relative weight loss of mice inoculated with 10⁶ EID₅₀ of virus or PBS (mock). B Virus titers in mice lungs. The error bars represent the standard deviations. C Neuraminidase activity values after normalization to renilla luciferase expression (relative activity). The activity values are displayed as mean ± SEM of three independent experiments containing three replicates. D Release efficiency of erythrocyte bound virions. Twofold dilutions of virus containing 1:128 HA units were incubated with equal volumes of 0.5% chicken erythrocytes at 4 °C for 1 h. The reduction in HA units was recorded for 4 h after incubation at 37 °C. **p < 0.01.