Investigating how the presence of neutrophils in the lungs prior to infection with respiratory viruses can exacerbate disease severity in mice

Respiratory viruses such as RSV, influenza viruses and the recently emerged SARS-CoV-2, represent a major global burden to public health. While infection with such viruses will often only result in mild "cold-like" symptoms, many will result in severe disease and require hospitalisation. Why some people get seriously ill while others only develop mild symptoms is not yet understood. Recent studies in both humans and mice have suggested that the presence of white blood cells, known as neutrophils, in the lungs prior to infection with respiratory virus results in more severe disease. The aim of this project is to investigate how the presence of these neutrophils alter the immune response to respiratory virus and ultimately how this drives more severe disease. To achieve our aims, we will use mouse models to characterise how and which parts of the immune environment in the lung that is changed by the presence of neutrophils prior to infection with respiratory virus and how this influence the severity of disease. This work will help us to better understand why some individuals are more at risk of severe disease following respiratory viral infection and help the development of effective treatments and vaccines.