title: Serum and nasal wash antibodies associated with resistance to experimental challenge with influenza A wild-type virus.
abstract: To identify immunological predictors of resistance to influenza A infection and illness, the immunological status of live and inactivated virus vaccines subsequently challenged with H1N1 or H3N2 wild-type virus was examined. We refer to prechallenge antibodies of vaccinees receiving live attenuated virus as infection induced and those receiving inactivated virus as inactivated vaccine induced. Inactivated vaccine-induced protection against wild-type virus infection or illness correlated with the level of neuraminidase-inhibiting antibody in serum, local hemagglutinin immunoglobulin G (IgG) (but not IgA) enzyme-linked immunosorbent assay antibody, and hemagglutination-inhibiting antibody in serum. In contrast, infection-induced resistance to wild-type virus infection correlated with local hemagglutinin IgA antibody and neuraminidase-inhibiting antibody in serum, but not with hemagglutination-inhibiting antibody in serum. These observations suggest that live vaccine virus infection-induced and inactivated vaccine-induced immunity may involve different compartments of the immune system; sufficient antibody in either serum or nasal secretions is capable of conferring resistance.
mesh_terms: D000914:Antibodies, Viral / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay; D006385:Hemagglutination Inhibition Tests; D006389:Hemagglutinins, Viral / Q000276:immunology; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D007140:Immunoglobulin Fab Fragments / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis; D009980:Influenza A virus / Q000276:immunology*; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000276:immunology; D009439:Neuraminidase / Q000276:immunology; D014613:Vaccines, Attenuated / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D006389:Hemagglutinins, Viral; D007070:Immunoglobulin A; D007140:Immunoglobulin Fab Fragments; D007074:Immunoglobulin G; D007252:Influenza Vaccines; D014613:Vaccines, Attenuated; D009439:Neuraminidase