Antigenic and Genetic Analysis of A/Hong Kong (H3N2) Influenza Viruses Isolated from Swine and Man

Self Cite

The complete nucleotide sequences of the neuraminidase (NA) genes of two reassortant (H1N2) and two H3N2 influenza A viruses isolated from pigs were determined and phylogenetic relationships between these and previously reported N2 NA genes were investigated. On the basis of pairwise nucleotide sequence identity, the NA genes of two reassortants, A/sw/Kanagawa/2/78 and A/sw/Ehime/1/80, were most closely related to those of human influenza A virus strains isolated in 1972 and the earliest available swine H3N2 influenza A viruses, respectively. Phylogenetic trees showed that the NA genes can be segregated into three groups, including lineages for (i) swine strains, (ii) the earliest human strain and (iii) recent human strains. The evolutionary tree for the 11 nucleotide and amino acid sequences suggested that the NAs of A/sw/HK/4/76 and A/sw/Kanagawa/2/78 belong to the lineage for recent human viruses. In contrast, the NA genes of the A/sw/HK/3/76 and H1N2 reassortant A/sw/Ehime/1/80 viruses were found to be of a swine lineage. The swine virus NA genes were further characterized by the cocirculation of two distinct lineages. Although the rates of synonymous (silent) substitutions for the swine and human viruses were nearly identical (0.00946 to 0.00884 per site per year), the rate of non-synonymous (amino acid changing) substitutions for swine virus NA genes was about 60% of that for the human virus.

Section: Discussionmentioning

confidence: 75%

Evolutionary pathways of N2 neuraminidases of swine and human influenza A viruses: origin of the neuraminidase genes of two reassortants (H1N2) isolated from pigs

Nerome

Kanegae

Yoshioka

et al. 1991

Self Cite

“…t Hyperimmune rabbit serum. :~ Antiserum monospecific for the isolated N2 NA of A/Aichi/2/68 virus was prepared as described previously (Nerome et al, 1981). § Homologous reactions are underlined.…”

Section: Analysis Of Gene Composition Of a Reassortant Virusmentioning

confidence: 99%

Origin and evolutionary characteristics of antigenic reassortant influenza A (H1N2) viruses isolated from man in China

Li¹,

Zhao²,

Gao³

et al. 1992

Self Cite

During the 1988/1989 influenza season, five antigenic reassortant influenza A (H 1N2) viruses not previously isolated from man were isolated in Hebei province, People's Republic of China. All isolates contained haemagglutinins (HAs) and neuraminidases (NAs) which were antigenically similar to those of the recent Russian (H1N1) and Hong Kong influenza A (H3N2) viruses, respectively. The results of antigenic and nucleotide sequence analyses revealed that the genes encoding the polymerase, nucleoprotein, NA, matrix and non-structural proteins of the reassortant A/Hebei/24/89 (H1N2) virus were derived from the H3N2 parent virus, whereas its HA gene was from the H1N1 parent virus. The nucleotide sequences of the HA (encoding the HA1 subunit) and NA genes of the reassortant viruses were also determined. Phylogenetic trees constructed from these data by the neighbourjoining method revealed that the HA gene of the reassortant virus was cl6sely related to those of recent human H 1N 1 viruses, whereas the NA gene was related to a recent human Hong Kong (H3N2) virus lineage.

“…The frequent transmission of H3N2 influenza viruses from man to swine has been documented by genome and antigen characterization of numerous H3N2 virus variants isolated from the above two hosts (Kundin, 1970;Shortridge et al, 1976Hinshaw et al, 1978;Shortridge & Webster, 1979;Kanai et al, 1981 ;Nerome et al, 1981 ;Nakajima et al, 1982). On the other hand, in a large-scale serological and virological survey conducted by research workers in several countries it was shown that swine (H1N1, formerly Hswl N1) virus different from the 'classical' strain has been rapidly circulating in the swine population of many areas of the world (Kendal et al, 1977;Hinshaw et al, 1978;Shortridge & Webster, 1979;Yamane et al, 1979;Pensaert et al, 1981;Sugimura et al, 1980;Nerome et al, 1982a).…”

Section: Introductionmentioning

confidence: 99%

Antigenic Characteristics and Genome Composition of a Naturally Occurring Recombinant Influenza Virus Isolated from a Pig in Japan

Nerome

Sakamoto

Yano

et al. 1983

Self Cite

SUMMARYWe performed antigenic analysis of the haemagglutinin and neuraminidase subunits of a recombinant virus (A/swine/Kanagawa/2/78) isolated from a pig in Japan in 1978, using a series of monoclonal antibodies to H1 (Hswl) haemagglutinin and N2 neuraminidases of H2N2 and H3N2 viruses. Results obtained in haemagglutination inhibition tests with five monoclonal antibodies to the haemagglutinin of A/N J/8/76 (H1N1) revealed that the haemagglutinin of three H1N1 and the recombinant viruses were indistinguishable from that of A/N J/8/76. The neuraminidase of A/swine/Kanagawa/2/78 was found to be antigenically similar to A/Kumamoto/22/76 (H3N2, A/Victoria/3/75-1ike strain). The oligonucleotide maps of the entire RNAs of H 1N 1, H1N2 and H3N2 viruses showed that A/swine/Kanagawa/2/78 (HIN2) virus was more similar to swine (H1N1) virus than to A/Kumamoto/22/76 (H3N2) virus. Radioactive cDNA was prepared by reverse transcription of the recombinant virus RNA using a dodecadeoxyribonucleotide primer and used in DNA-RNA hybridization experiments. The results obtained in molecular hybridization based on blotting procedures showed that all cDNA segments except gene 6 hybridized efficiently with RNAs of swine (H 1N 1) influenza virus. The sixth cDNA segment was homologous to the corresponding RNA segment of H3N2 virus. The genetic relatedness of A/swine/Kanagawa/2/78 (H1N2) with either A/swine/Kanagawa/4/78 (HIN 1) or A/Kumamoto/22/76 (H3N2) was clearly established by hybridization between the cDNA segment probes and viral RNA. It was concluded that the neuraminidase gene of A/swine/Kanagawa/2/78 (H1N2) was derived from a human H3N2 virus, while the seven other genes were from a swine H1N1 virus.