RT Journal Article SR Electronic(1) A1 Nerome, Kuniaki A1 Sakamoto, Shinichi A1 Yano, Noriko A1 Yamamoto, Tadashi A1 Kobayashi, Susumu A1 Webster, Robert G. A1 Oya, AkiraYR 1983 T1 Antigenic Characteristics and Genome Composition of a Naturally Occurring Recombinant Influenza Virus Isolated from a Pig in Japan JF Journal of General Virology, VO 64 IS 12 SP 2611 OP 2620 DO https://doi.org/10.1099/0022-1317-64-12-2611 PB Microbiology Society, SN 1465-2099, AB SUMMARY We 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 (Hsw1) haemagglutinin and N2 neuraminidases of H2N2 and H3N2 viruses. Results obtained in haemagglutination inhibition tests with five monoclonal antibodies to the haemagglutinin of A/NJ/8/76 (H1N1) revealed that the haemagglutinin of three H1N1 and the recombinant viruses were indistinguishable from that of A/NJ/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-like strain). The oligonucleotide maps of the entire RNAs of H1N1, H1N2 and H3N2 viruses showed that A/swine/Kanagawa/2/78 (H1N2) 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 (H1N1) 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 (H1N1) 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., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-64-12-2611