T Helper Lymphocyte Response to Respiratory Syncytial Virus and Its Components in Patients with Respiratory Allergy and Nonatopic Controls

BACKGROUND: Respiratory syncytial virus (RSV) G protein is involved in Th2-shifted immune response, while F protein has a reverse effect on RSV infection in Th2-prone BALB/c mice. Studies on the human T cell response to F or G protein are few, and the relationship between the immune response to G protein and atopy is not known. METHODS: We established CD4+ RSV-specific T cell lines (TCLs) from adult patients with respiratory allergic diseases (allergics) or nonatopic controls (controls), and examined proliferative responses and gamma-interferon (IFN-gamma) and interleukin 4 (IL-4) production in these TCLs upon stimulation with RSV, F or G proteins. RESULTS: 32 and 29 RSV-specific oligoclonal TCLs were established from allergics and controls, respectively. IL-4/IFN-gamma in the culture supernatant of antigen-stimulated TCLs was significantly higher in allergics than in controls (p = 0.042). IL-4/IFN-gamma ratios in the culture supernatants of G-protein-reactive TCLs were significantly higher in allergics than in controls (p = 0.016), while no differences in IL-4/IFN-gamma in culture supernatants of F-protein-reactive TCLs were found between allergics and controls (p = 0.787). IL-4/IFN-gamma in the culture supernatants of G-protein-reactive TCLs was significantly higher than those of F-protein-reactive TCLs in allergics (p = 0.023) but not in controls (p = 0.768). CONCLUSION: The results suggest that the T cell response to RSV is influenced by the atopic diathesis as well as by individual RSV antigens, and that G protein may be an important antigen involved in allergy in humans.