Evaluation of live and inactivated influenza A virus vaccines in a mouse model.
Induction of cross-protective immunity against serologically distinct subtypes of influenza A virus in mice was examined in an attempt to correlate cross-protection with heterotypic lymphocyte responses. Live and inactivated virus vaccines protected against the homologous subtype, but only whole virus protected against heterologous subtypes. Live virus vaccines provided better cross-protection than inactivated virus vaccines. A weak defense against heterotypic challenge generated by live H0N1 virus could be boosted by cross-stimulation with whole H3N2 virus and by restimulation with pathogenic H0N1 virus. Heterotypic protection persisted for at least five months. Live viruses induced cross-reactive cytotoxic T cells in normal mice. However, cross-stimulation with heterologous virus was required to generate secondary cytotoxicity. Cross-reactive B lymphocytes were evident after inoculation with whole virus.
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology; D003429:Cross Reactions; D003602:Cytotoxicity, Immunologic; D004195:Disease Models, Animal; D006801:Humans; D007117:Immunization, Secondary; D009980:Influenza A virus / Q000276:immunology*; D007252:Influenza Vaccines; D051379:Mice; D008807:Mice, Inbred BALB C; D013601:T-Lymphocytes / Q000276:immunology; D013997:Time Factors; D014613:Vaccines, Attenuated
D007252:Influenza Vaccines; D014613:Vaccines, Attenuated