title: Influenza A neuraminidase antibodies in children and young adults studied by serum absorption.
abstract: A study is described of influenza A anti-neuraminidase antibodies in the sera of young people of three different groups. Each serum was individually absorbed with viruses containing the N2 neuraminidases of 1957, 1968 and 1972. Rabbit antisera prepared against the viruses were similarly absorbed. Results obtained with the animal sera suggested that these neuraminidases were antigenically distinct, but the human sera had a broader range of anti-neuraminidase activity and gave indication of asymmetric antigenic relationships. Earlier workers who surveyed anti-haemagglutinin antibodies reported that the virus of primary infection absorbed all antibodies, and the virus of secondary infection only those directed against itself. We too found that the virus of secondary infection absorbed only homologous anti-neuraminidase antibody. However, although the primary infecting virus did absorb some secondary antibody, this absorption was incomplete and it lessened with the lengthening of the time interval between the primary and secondary infecting viruses. A similar pattern was seen with anti-haemagglutinin antibodies. Absorption of anti-neuraminidase antibodies from human sera proved much more difficult than absorption of anti-haemagglutinin antibodies particularly after repeated influenza virus infections. The relative rarity of antigenic shift in the neuraminidase subunit also creates problems in the interpretation of results of serum neuraminidase antibody surveys.
mesh_terms: D000328:Adult; D000914:Antibodies, Viral; D000918:Antibody Specificity; D002648:Child; D004739:England; D006385:Hemagglutination Inhibition Tests; D006723:Hong Kong; D006801:Humans; D007106:Immune Sera; D009980:Influenza A virus / Q000276:immunology; D007251:Influenza, Human / Q000201:enzymology / Q000276:immunology*; D009439:Neuraminidase / Q000276:immunology*; D012846:Singapore
chemical_list: D000914:Antibodies, Viral; D007106:Immune Sera; D009439:Neuraminidase
references.citation: Infect Immun. 1976 Jan;13(1):1-8
references.pmid: 814097
references.citation: J Infect Dis. 1972 Jul;126(1):61-8
references.pmid: 4114028
references.citation: J Exp Med. 1974 Dec 1;140(6):1559-70
references.pmid: 4139233
references.citation: J Exp Med. 1974 Dec 1;140(6):1571-8
references.pmid: 4139234
references.citation: Bull World Health Organ. 1969;41(3):643-5
references.pmid: 5309489
references.citation: J Exp Med. 1966 Sep 1;124(3):331-45
references.pmid: 5922742
references.citation: Trans Assoc Am Physicians. 1953;66:231-9
references.pmid: 13136267
references.citation: J Exp Med. 1956 Aug 1;104(2):199-209
references.pmid: 13345965
references.citation: Br Med J. 1958 Feb 1;1(5065):259-61
references.pmid: 13499916