Obesity and influenza virus: Is elevated leptin the mechanism for increased infection severity?

Previous work from our laboratory demonstrated that obese mice have alterations in antiviral cytokine gene expression when infected with the influenza virus. Since these cytokines play a major role in the infected cells’ innate immune response, we evaluated the effects of leptin dosage on expression of several cytokines during a flu infection in human alveolar lung epithelium (A549 cells). Following 48 hours of infection by influenza A/Puerto Rico/8/1934 H1N1, increasing leptin dosage resulted in significant decreases in expression of interferon-α (IFNα) and monocyte chemotactic protein-1 (MCP-1); a strong, similar trend was found for IFNβ, but it was not statistically significant. No leptin dosage trends were found for IL-6 or for the amount of viral particles released by cells into the supernatant. These data suggest that leptin contributes to the increased flu severity in obese individuals by weakening the innate immune response.Bachelor of Science in Public Healt