56°C-inactivated influenza virus induces cytokines in human neutrophils. Human neutrophils (10⁶ cells) were incubated with GM-CSF (100 U/mL) for 30 minutes, then stimulated with influenza virus (Hong Kong, 500 000 HA), influenza virus treated at 56°C for 30 minutes, or influenza virus treated at 100°C for 30 minutes. Supernatants were collected at 24 hours and IL-8 was measured by ELISA. Error bars represent the SD of triplicate samples. Data shown are representative of at least 3 independent experiments.