Statistical analyses (Spearmans rank correlations and Wilcoxon matched -paired signed-rank tests) were performed using the Stata/IC 10.0 (Stata corporation, College Station, Tx U.S.A.). Due to the exploratory nature of the study there was no correction for multiple comparisons, and calculated p values are reported herein.  Baculovirus-based Vaccine Displaying Respiratory Syncytial Virus Glycoprotein Induces Protective Immunity against RSV Infection without Vaccine-Enhanced Disease BACKGROUND: Respiratory syncytial virus (RSV) is a major cause of severe lower respiratory tract diseases in infancy and early childhood. Despite its importance as a pathogen, there is no licensed vaccine against RSV yet. The attachment glycoprotein (G) of RSV is a potentially important target for protective antiviral immune responses. Recombinant baculovirus has been recently emerged as a new vaccine vector, since it has intrinsic immunostimulatory properties and good bio-safety profile. METHODS: We have constructed a recombinant baculovirus-based RSV vaccine, Bac-RSV/G, displaying G glycoprotein, and evaluated immunogenicity and protective efficacy by intranasal immunization of BALB/c mice with Bac-RSV/G. RESULTS: Bac-RSV/G efficiently provides protective immunity against RSV challenge. Strong serum IgG and mucosal IgA responses were induced by intranasal immunization with Bac-RSV/G. In addition to humoral immunity, G-specific Th17- as well as Th1-type T-cell responses were detected in the lungs of Bac-RSV/G-immune mice upon RSV challenge. Neither lung eosinophilia nor vaccine-induced weight loss was observed upon Bac-RSV/G immunization and subsequent RSV infection. CONCLUSION: Our data demonstrate that intranasal administration of baculovirus-based Bac-RSV/G vaccine is efficient for the induction of protection against RSV and represents a promising prophylactic vaccination regimen. Respiratory syncytial virus (RSV) is the most important viral pathogen of causing serious bronchiolitis and pneumonia in infants and young children worldwide. RSV is also receiving increasing recognition as an important cause of lower respiratory tract illness in immunocompromised patients, the young children, and the elderly (1) (2) (3) . Despite the importance of RSV as a respiratory pathogen, there is no licensed vaccine currently available against RSV infection.