An experimental influenza subunit vaccine (iscom): induction of protective immunity to challenge infection in mice after intranasal or subcutaneous administration.

An experimental influenza virus (A/PR/8/34(H1N1] vaccine was tested and evaluated in mice. The mice were inoculated once or twice intranasally or subcutaneously with 1 or 10 micrograms of iscoms prior to challenge with high dose of live virus. It was demonstrated that two intranasal administrations were as efficient as two s.c. administrations, both routes inducing high levels of antibody and protection against challenge infection. With a one-dose regimen, the s.c. route induced a somewhat higher antibody response than the intranasal route; this might be explained by technical difficulties connected with an intranasal administration.