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W G Laver

Publications and source records attributed to W G Laver.

140 records · Page 8Linked to original sources
PubMed1968

Antiviral activity of antiserum specific for an influenza virus neuraminidase.

Antiserum specific for influenza A(2) neuraminidase was produced by immunization of rabbits with the purified enzyme which had been isolated by electrophoresis from the proteins of a detergent-disrupted A(0)A(2) influenza virus recombinant [X-7 (F1)]. This recombinant contained hemagglutinin of the A(0) subtype and A(2) neuraminidase. Antiserum to the isolated A(2) neuraminidase did not react in any of four serological tests with A(0) or A(2) subtype viruses that lacked the A(2) enzyme. In contrast, the antiserum inhibited the neuraminidase activity only of wild-type and recombinant viruses containing the A(2) enzyme, regardless of the nature of their hemagglutinin proteins. The antiserum caused hemagglutination-inhibition of some, but not all, viruses bearing the A(2) enzyme, and it reduced the plaque size or plaque number of all viruses tested that contained A(2) neuraminidase. In the chick embryo and in cell culture, low dilutions of antiserum reduced the yield of virus. True neutralization of virus in the chick embryo did not occur. We conclude that an antiserum specific for A(2) neuraminidase influenced the yield and release of virus from influenza virus-infected cells.

Animals↗
PubMed1967

Adenovirus proteins. II. N-terminal amino acid analysis.

Adenovirus types 2, 4, 5, 6, 18, 21 and 27, were analyzed for N-terminal amino acids by use of (35)S-labeled phenylisothiocyanate of high specific radioactivity. Two free N-terminal amino acids, alanine and glycine, were found in these viruses in the molar ratio (alanine-glycine) of 2.5:1, with the exception of type 2 where the ratio was 3.6:1 and type 5 where the ratio was 5.5:1 Adenovirus type 2 was disrupted by acetone treatment, and two protein fractions were obtained after sucrose gradient centrifugation. One of these fractions, which was associated with the viral deoxyribonucleic acid and comprised approximately 18% of the total protein of the virus, was greatly enriched with respect to N-terminal alanine and glycine.

Adenoviridae↗
PubMedDate not supplied

Structure of the influenza virus glycoprotein antigen neuraminidase at 2.9 A resolution.

The influenza virus neuraminidase glycoprotein is a tetramer with a box-shaped head, 100 X 100 X 60 A, attached to a slender stalk. The three-dimensional structure of neuraminidase heads shows that each monomer is composed of six topologically identical beta-sheets arranged in a propeller formation. The tetrameric enzyme has circular 4-fold symmetry stabilized in part by metal ions bound on the symmetry axis. Sugar residues are attached to four of the five potential glycosylation sequences, and in one case contribute to the interaction between subunits in the tetramer.

Antigens, Viral↗
PubMedDate not supplied

Structure of the catalytic and antigenic sites in influenza virus neuraminidase.

The catalytic sites of influenza virus neuraminidase are located on the upper corners of the box-shaped tetramer that forms the head of the molecule. Antigenic determinants form a nearly-continuous surface across the top of the monomer encircling the catalytic site. Approximately the same number of amino acid sequence changes occurred in these determinants between the years 1968 and 1975 as occurred in the antigenic sites of influenza virus haemagglutinin in the same period.

Amino Acid Sequence↗
PubMedDate not supplied

Three-dimensional structure of a complex of antibody with influenza virus neuraminidase.

The structure of a complex between influenza virus neuraminidase and an antibody displays features inconsistent with the inflexible 'lock and key' model of antigen-antibody binding. The structure of the antigen changes on binding, and that of the antibody may also change; the interaction therefore has some of the character of a handshake.

Amino Acid Sequence↗
PubMedDate not supplied

Potentiation of the immune response to influenza virus subunit vaccines.

Influenza subunit vaccines are poorly immunogenic in unprimed lower animals and man and a method was sought to potentiate the humoral response. Intact heterologous influenza A virus vaccine (A/Victoria/3/75 [H3N2]) potentiated the antibody response of hamsters to A/NJ/76 [Hsw1 N1] subunit vaccines but large doses of intact virus were required. Studies in seronegative young human adults showed that much lower doses of homologous A/NJ/76 [Hsw1 N1] virus potentiated the antibody response to both the hemagglutinin and neuraminidase subunits of A/NJ/76 influenza vaccines. This suggests that future influenza subunit vaccines for use in seronegative people should contain a small amount of whole virus vaccine, sufficient to potentiate the immune response to the subunits but insufficient to be reactogenic.

Adolescent↗