As people age, their immune system becomes less robust. This makes them more susceptible to serious and frequently life-threatening infections with viruses that affect the respiratory tract such as influenza A virus (IAV).
Stanley Perlman and colleagues, at the University of Iowa, Iowa City, have now identified a new immune system defect in aged mice that makes them more susceptible than young mice to developing severe clinical disease upon infection with respiratory viruses such as IAV. Importantly, they were able to reverse the defect by inhibiting the immune molecule PGD2. Perlman and colleagues therefore suggest that inhibition of PGD2 could provide a way to improve clinical outcomes in older patients with severe respiratory viral infections and perhaps more importantly enhance the efficacy of flu vaccines in the elderly.