Immune-mediated disease pathogenesis in respiratory syncytial virus infection

Respiratory syncytial virus (RSV) is an important cause of severe respirato ry disease in persons at both extremes of age. Wheezing is a cardinal sign of infection and the illness is associated with an increased incidence of c hildhood asthma. Data from both humans and animal models have linked severe disease in infants and the syndrome of vaccine-enhanced illness with an ab errant composition of CD4 + T cells, suggestive of an exaggerated Th2 respo nse. Studies in murine models have shown that prior vaccination, coexisting allergic inflammation, or direct modulation of the cytokine milieu can pro foundly influence the immune response to RSV and thereby affect the express ion of disease. in addition, there are intrinsic antigenic properties of th e RSV G glycoprotein that promote Th2 responses and eosinophilia. This pape r proposes an integrated working model of how host and virus factors intera ct to determine the characteristics of RSV-induced illness. This model sugg ests strategies for the development of new vaccine and immunotherapeutic in terventions, and creates a framework for asking additional questions about the immunopathogenesis of RSV. (C) 2000 Elsevier Science B.V, All rights re served.