1. CpG ODN enhances the efficacy of F protein vaccine against respiratory syncytial virus infection in the upper respiratory tract via CD4+ T cells.
- Author
-
Kawahara, Eigo, Yamamoto, Shinya, Shibata, Takehiko, Hirai, Toshiro, and Yoshioka, Yasuo
- Subjects
- *
RESPIRATORY syncytial virus infection vaccines , *RESPIRATORY syncytial virus infections , *RESPIRATORY infections , *T cells , *TH1 cells - Abstract
Respiratory syncytial virus (RSV) is a leading cause of severe respiratory illness worldwide, particularly in infants and older adults. Vaccines targeting the fusion glycoprotein (F protein) —one of the surface antigens of RSV— are highly effective in preventing RSV-associated severe lower respiratory tract disease. However, the efficacy of these vaccines against upper respiratory tract challenge needs improvement. Here, we aimed to examine the efficacy of F protein vaccines with or without CpG oligodeoxynucleotide (CpG ODN) as an adjuvant in the upper and lower respiratory tracts in mice. F + CpG ODN induced higher levels of F-specific IgG than that induced by F alone; however, levels of neutralizing antibodies did not increase compared to those induced by F alone. F + CpG ODN induced T helper 1 (Th1) cells while F alone induced T helper 2 (Th2) cells. Moreover, F + CpG ODN improved the protection against RSV challenge in the upper respiratory tract compared to F alone, which was largely dependent on CD4+ T cells. Meanwhile, both F + CpG ODN and F alone protected the lower respiratory tract. In conclusion, we demonstrated that induction of F-specific Th1 cells is an effective strategy to prevent RSV challenge in the upper respiratory tract in F protein vaccines. These data support the development of novel F protein vaccines. • F protein vaccine efficacy in the upper respiratory tract (URT) needs improvement. • We examined the potential of CpG ODN to improve F protein efficacy in mice. • F + CpG ODN increases F-specific Th1 cells but not neutralizing antibody levels. • F + CpG ODN improves protection against RSV challenge in the URT. • CD4+ T cells help protect against RSV challenge in the URT. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF