Simultaneous aerosol and intra-muscular immunization with influenza vaccine induces powerful protective local T cell and systemic Ab immune responses in pigs

• Published in: bioRxiv 2020-09
• Main Authors: Martini, Veronica, Basu Paudyal, Chrun, Tiphany, Mcnee, Adam, Edmans, Matthew, Maze, Emmanuel, Clark, Beckie, Nunez, Alejandro, Dolton, Garry, Sewell, Andrew, Beverley, Peter, Macloughlin, Ronan, Townsend, Alain, Tchilian, Elma
• Format: Article
• Language: English
• Subjects: Aerosols; Antibodies; Immune response (cell-mediated); Immunization; Influenza; Lymphocytes; Lymphocytes T; Respiratory diseases; Respiratory tract; Vaccines; Viruses
• DOI: 10.1101/2020.09.10.291625

Abstract A vaccine providing both powerful antibody and cross-reactive T cell immune responses against influenza viruses would be beneficial for both humans and pigs. Here we evaluated intramuscular (IM), aerosol (Aer) and simultaneous immunization (SIM) by both routes in pigs, using the single cycle candidate influenza vaccine S-FLU. After prime and boost immunization pigs were challenged with H1N1pdm09 virus. IM immunized pigs generated high titer of neutralizing antibodies but poor T cell responses, while Aer induced powerful respiratory tract T cell responses, but a low titer of antibodies. SIM pigs combined high antibody titers and strong local T cell responses. SIM pigs showed the most complete suppression of virus shedding and the greatest improvement in pathology. We conclude that SIM regimes for immunization against respiratory pathogens warrant further study. Competing Interest Statement AT is named on a patent concerning the use of S-FLU as a vaccine. RM is employed by Aerogen Limited, focused on development of vibrating mesh nebulizer technologies. The other authors have no financial conflicts of interest.