How cigarette smoke negatively impacts the consequences of viral infections

Jack Elias and colleagues, at Yale University School of Medicine, have performed new studies in mice that provide mechanistic insight into why viral infections have more severe consequences in individuals exposed to cigarette smoke than in those not exposed to cigarette smoke (e.g., influenza-infected smokers have increased mortality when compared with influenza-infected nonsmokers). In the study, a combination of cigarette smoke and compounds that mimic viral components were found to cause more severe airway damage in a mouse model of the lung disease chronic obstructive pulmonary disease than the compounds that mimic viral components alone. Further, cigarette smoke enhanced the effects of influenza in mice. The effects of the combination of cigarette smoke and the compounds that mimic viral components were associated with an increased immune response in the lung and detailed analysis identified the molecular pathways involved. In an accompanying commentary, Rubin Tuder and Jeong Yun, at the University of Colorado Denver School of Medicine, explain the importance of defining the signaling pathways involved in the cigarette smoke–enhanced effects of viral infection for human disease.

Source: Journal of Clinical Investigation