{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T09:06:18Z","timestamp":1790845578184,"version":"4.1.0"},"reference-count":50,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2015,12,25]],"date-time":"2015-12-25T00:00:00Z","timestamp":1451001600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Pearl River S&amp;T Nova program of Guangzhou","award":["No. 2014J2200033"],"award-info":[{"award-number":["No. 2014J2200033"]}]},{"name":"the Natural Science Foundation of China","award":["U1301224"],"award-info":[{"award-number":["U1301224"]}]},{"name":"Shanghai Joint Research Projects on the Prevention and Control of Avian Influenza H7N9 Virus","award":["2013QLG010"],"award-info":[{"award-number":["2013QLG010"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Influenza A viruses (IAVs) cause seasonal pandemics and epidemics with high morbidity and mortality, which calls for effective anti-IAV agents. The glycoprotein hemagglutinin of influenza virus plays a crucial role in the initial stage of virus infection, making it a potential target for anti-influenza therapeutics development. Here we found that quercetin inhibited influenza infection with a wide spectrum of strains, including A\/Puerto Rico\/8\/34 (H1N1), A\/FM-1\/47\/1 (H1N1), and A\/Aichi\/2\/68 (H3N2) with half maximal inhibitory concentration (IC50) of 7.756 \u00b1 1.097, 6.225 \u00b1 0.467, and 2.738 \u00b1 1.931 \u03bcg\/mL, respectively. Mechanism studies identified that quercetin showed interaction with the HA2 subunit. Moreover, quercetin could inhibit the entry of the H5N1 virus using the pseudovirus-based drug screening system. This study indicates that quercetin showing inhibitory activity in the early stage of influenza infection provides a future therapeutic option to develop effective, safe and affordable natural products for the treatment and prophylaxis of IAV infections.<\/jats:p>","DOI":"10.3390\/v8010006","type":"journal-article","created":{"date-parts":[[2015,12,28]],"date-time":"2015-12-28T04:23:49Z","timestamp":1451276629000},"page":"6","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":348,"title":["Quercetin as an Antiviral Agent Inhibits Influenza A Virus (IAV) Entry"],"prefix":"10.3390","volume":"8","author":[{"given":"Wenjiao","family":"Wu","sequence":"first","affiliation":[{"name":"State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richan","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xianglian","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jian","family":"He","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shibo","family":"Jiang","sequence":"additional","affiliation":[{"name":"Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA"},{"name":"Key Lab of Medical Molecular Virology of Ministries of Education and Health, Shanghai Medical College, Fudan University, Shanghai 200032, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6346-5006","authenticated-orcid":false,"given":"Shuwen","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Yang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China"},{"name":"Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2015,12,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1126\/science.1176225","article-title":"Antigenic and genetic characteristics of swine-origin 2009 A(H1N1) influenza viruses circulating in humans","volume":"325","author":"Garten","year":"2009","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"357","DOI":"10.1038\/modpathol.2012.193","article-title":"Pathological study of archival lung tissues from five fatal cases of avian H5N1 influenza in Vietnam","volume":"26","author":"Nakajima","year":"2013","journal-title":"Mod. 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