title: Parameters of humoral and cellular immunity of influenza A/USSR/90/77 (H1N1) virus in various age groups.
abstract: After a local epidemic of A/USSR influenza, immunologic parameters related to influenza A/USSR/90/77 (H1N1) virus were studied in four age groups: elderly persons (greater than or equal to 64 years), healthy adults (20-44 years), children (six to 13 years), and neonates (who served as controls). Sera from the first three groups had nearly equivalent titers of hemagglutination-inhibiting antibody (geometric mean titers, 1:8-1:11), which were greater than those in cord blood of neonates. Lymphocyte proliferation responses to influenza A/USSR viral antigens among study groups were similar, with mean stimulation ratios (to whole virus) of 4.2-5.4; neonatal cord blood samples were unresponsive (stimulation ratio, 1.1). In contrast, the magnitude of antibody-dependent cellular cytotoxicity against baby hamster kidney target cells infected with influenza A/USSR virus was significantly greater with lymphocytes from adults and elderly persons (P less than 0.05) than with those from children.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000917:Antibody Formation; D000956:Antigens, Viral / Q000276:immunology; D002648:Child; D003601:Cytotoxicity Tests, Immunologic; D006801:Humans; D007111:Immunity, Cellular; D053118:Influenza A Virus, H1N1 Subtype; D009980:Influenza A virus / Q000276:immunology*; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology / Q000502:physiology; D008875:Middle Aged
chemical_list: D000956:Antigens, Viral