{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T21:46:25Z","timestamp":1789076785709,"version":"build-2803163510"},"reference-count":48,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2024,6,27]],"date-time":"2024-06-27T00:00:00Z","timestamp":1719446400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Major Scientific and Technological Innovation Project (MSTIP) of Shandong Province","award":["2023CXGC010705"],"award-info":[{"award-number":["2023CXGC010705"]}]},{"name":"The Major Scientific and Technological Innovation Project (MSTIP) of Shandong Province","award":["2024SKLVPHS03"],"award-info":[{"award-number":["2024SKLVPHS03"]}]},{"name":"The State Key Laboratory of Veterinary Public Health and Safety","award":["2023CXGC010705"],"award-info":[{"award-number":["2023CXGC010705"]}]},{"name":"The State Key Laboratory of Veterinary Public Health and Safety","award":["2024SKLVPHS03"],"award-info":[{"award-number":["2024SKLVPHS03"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Swine influenza viruses (SIVs) have been circulating in swine globally and are potential threats to human health. During the surveillance of SIVs in Shandong Province, China, from 2019 to 2022, 21 reassortant G4 genotype Eurasian avian-like (EA) H1N1 subtypes containing genes from the EA H1N1 (HA and NA), 2009 pandemic (pdm\/09) H1N1 virus (PB2, PB1, PA, NP, and M), and classical swine (CS) H1N1 (NS) lineages were isolated. The analysis of the key functional amino acid sites in the isolated viruses showed that two mutation sites (190D and 225E) that preferentially bind to the human \u03b12-6 sialic acid receptor were found in HA. In PB2, three mutation sites (271A, 590S, and 591R) that may increase mammalian fitness and a mutation site (431M) that increases pathogenicity in mice were found. A typical human signature marker that may promote infection in humans, 357K, was found in NP. The viruses could replicate efficiently in mouse lungs and turbinates, and one of the H1N1 isolates could replicate in mouse kidneys and brains without prior adaption, which indicates that the viruses potentially pose a threat to human health. Histopathological results showed that the isolated viruses caused typical bronchopneumonia and encephalitis in mice. The results indicate that G4 genotype H1N1 has potential transmissibility to humans, and surveillance should be enhanced, which could provide important information for assessing the pandemic potential of the viruses.<\/jats:p>","DOI":"10.3390\/genes15070849","type":"journal-article","created":{"date-parts":[[2024,6,28]],"date-time":"2024-06-28T03:42:30Z","timestamp":1719546150000},"page":"849","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Swine Influenza Viruses Isolated from 2019 to 2022 in Shandong Province, China, Exemplify the Dominant Genotype"],"prefix":"10.3390","volume":"15","author":[{"given":"Yuzhong","family":"Zhao","sequence":"first","affiliation":[{"name":"College of Animal Science and Veterinary Medicine, Shandong Agricultural University, 61 Daizong Street, Tai\u2019an 271018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lebin","family":"Han","sequence":"additional","affiliation":[{"name":"College of Animal Science and Veterinary Medicine, Shandong Agricultural University, 61 Daizong Street, Tai\u2019an 271018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haotian","family":"Sang","sequence":"additional","affiliation":[{"name":"College of Animal Science and Veterinary Medicine, Shandong Agricultural University, 61 Daizong Street, Tai\u2019an 271018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sidang","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Animal Science and Veterinary Medicine, Shandong Agricultural University, 61 Daizong Street, Tai\u2019an 271018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pingping","family":"Yang","sequence":"additional","affiliation":[{"name":"College of Animal Science and Veterinary Medicine, Shandong Agricultural University, 61 Daizong Street, Tai\u2019an 271018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanmeng","family":"Hou","sequence":"additional","affiliation":[{"name":"College of Animal Science and Veterinary Medicine, Shandong Agricultural University, 61 Daizong Street, Tai\u2019an 271018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0857-8080","authenticated-orcid":false,"given":"Yihong","family":"Xiao","sequence":"additional","affiliation":[{"name":"College of Animal Science and Veterinary Medicine, Shandong Agricultural University, 61 Daizong Street, Tai\u2019an 271018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1111\/j.1750-2659.2010.00148.x","article-title":"Historical thoughts on influenza viral ecosystems, or behold a pale horse, dead dogs, failing fowl, and sick swine","volume":"4","author":"Morens","year":"2010","journal-title":"Influenza Other Respir. 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