NEW YORK (Reuters Health) Feb 01 - An influenza vaccine administered sublingually protects mice against lethal infection, according to a report in the January 28th Early Edition of the Proceedings of the National Academy of Sciences.
In the study, Dr. Mi-Na Kweon, from the International Vaccine Institute in Seoul, Korea, and colleagues administered formalin-inactivated or live influenza A/PR/8 (H1N1) virus to mice via the sublingual route.
Vaccination with the inactivated virus induced systemic and mucosal anti-influenza antibodies and protected against lethal intranasal challenge with influenza virus. The addition of a mucosal adjuvant enhanced the antibody response and protected against respiratory viral challenge.
Further analysis showed that the inactivated virus, administered sublingually, caused expansion of interferon-gamma-secreting T cells and enhanced virus-specific cytotoxic T cell responses.
Sublingual administration of the live vaccine was not pathogenic and produced heterosubtypic protection against respiratory challenge with H3N2 virus.
In contrast to what has been seen with intranasally administered influenza vaccine, sublingually administered vaccine did not travel to or replicate in the central nervous system.
"Based on these promising findings, we propose that the sublingual mucosal route offers an attractive alternative to mucosal routes for administering influenza vaccines," the authors conclude.
Proc Natl Acad Sci USA 2008
In the study, Dr. Mi-Na Kweon, from the International Vaccine Institute in Seoul, Korea, and colleagues administered formalin-inactivated or live influenza A/PR/8 (H1N1) virus to mice via the sublingual route.
Vaccination with the inactivated virus induced systemic and mucosal anti-influenza antibodies and protected against lethal intranasal challenge with influenza virus. The addition of a mucosal adjuvant enhanced the antibody response and protected against respiratory viral challenge.
Further analysis showed that the inactivated virus, administered sublingually, caused expansion of interferon-gamma-secreting T cells and enhanced virus-specific cytotoxic T cell responses.
Sublingual administration of the live vaccine was not pathogenic and produced heterosubtypic protection against respiratory challenge with H3N2 virus.
In contrast to what has been seen with intranasally administered influenza vaccine, sublingually administered vaccine did not travel to or replicate in the central nervous system.
"Based on these promising findings, we propose that the sublingual mucosal route offers an attractive alternative to mucosal routes for administering influenza vaccines," the authors conclude.
Proc Natl Acad Sci USA 2008