{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T11:27:00Z","timestamp":1772105220853,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T00:00:00Z","timestamp":1772064000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100009619","name":"Japan Agency for Medical Research and Development","doi-asserted-by":"publisher","award":["JP24fk0210132"],"award-info":[{"award-number":["JP24fk0210132"]}],"id":[{"id":"10.13039\/100009619","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100009619","name":"Japan Agency for Medical Research and Development","doi-asserted-by":"publisher","award":["JP25fk0210132"],"award-info":[{"award-number":["JP25fk0210132"]}],"id":[{"id":"10.13039\/100009619","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["JP23K15055"],"award-info":[{"award-number":["JP23K15055"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Hepatitis A virus (HAV) infection can occasionally cause acute severe hepatitis. Patients with this disease sometimes need to undergo liver transplantation with immunosuppressants. Although rare, breakthrough HAV infections, despite vaccination, appear to be more common among immunocompromised populations. The effect of immunosuppressants on HAV replication is unclear. In this study, we examined the effects of immunosuppressants on HAV HA11-1299 genotype IIIA replication in human hepatocytes, finding that azathioprine inhibited HAV replication with a half-maximal inhibitory concentration of 0.967 \u03bcmol\/L. We further examined the effect of azathioprine on the replication of HAV HM175 18f genotype IB using replication-competent or replication-incompetent subgenomic replicon in HuhT7 cells. Azathioprine had significant inhibitory effects on the HAV replication-competent subgenomic replicon compared to the replication-incompetent subgenomic replicon. The effect of azathioprine on the activity of the HAV HM175 18f genotype IB-internal ribosomal entry site (IRES) was investigated in COS7-HAV-IRES cells using a reporter assay. Azathioprine at 1 \u03bcmol\/L had a significant inhibitory effect on HAV IRES activity but at 0.5 \u03bcmol\/L had no inhibitory effect. Azathioprine appears to inhibit HAV replication as well as HAV translation. In conclusion, we found that azathioprine inhibits HAV replication in human hepatocytes, meaning that it may be useful for patients with a HAV infection who need to use immunosuppressants.<\/jats:p>","DOI":"10.3390\/pathogens15030249","type":"journal-article","created":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T10:33:02Z","timestamp":1772101982000},"page":"249","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Azathioprine Inhibits Hepatitis A Virus Replication In Vitro"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-8135-342X","authenticated-orcid":false,"given":"Tatsuo","family":"Kanda","sequence":"first","affiliation":[{"name":"Division of Gastroenterology and Hepatology, Uonuma Institute of Community Medicine, Niigata University Medical and Dental Hospital, Uonuma Kikan Hospital, 4132 Urasa, Minamiuonuma 949-7302, Japan"},{"name":"Department of General Medicine, Uonuma Kikan Hospital, 4132 Urasa, Minamiuonuma 949-7302, Japan"},{"name":"Division of Gastroenterology and Hepatology, Graduate School of Medical and Dental Sciences, Niigata University, 1-757 Aasahimachi-Dori, Chuo-ku, Niigata 951-8520, Japan"},{"name":"Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, 30-1 Oyaguchi Kamicho, Itabashi-ku, Tokyo 173-8610, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2681-0776","authenticated-orcid":false,"given":"Reina","family":"Sasaki-Tanaka","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology and Hepatology, Graduate School of Medical and Dental Sciences, Niigata University, 1-757 Aasahimachi-Dori, Chuo-ku, Niigata 951-8520, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2618-7494","authenticated-orcid":false,"given":"Hiroyuki","family":"Abe","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology and Hepatology, Graduate School of Medical and Dental Sciences, Niigata University, 1-757 Aasahimachi-Dori, Chuo-ku, Niigata 951-8520, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7138-1785","authenticated-orcid":false,"given":"Takeshi","family":"Yokoo","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology and Hepatology, Graduate School of Medical and Dental Sciences, Niigata University, 1-757 Aasahimachi-Dori, Chuo-ku, Niigata 951-8520, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Akira","family":"Sakamaki","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology and Hepatology, Graduate School of Medical and Dental Sciences, Niigata University, 1-757 Aasahimachi-Dori, Chuo-ku, Niigata 951-8520, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3764-3598","authenticated-orcid":false,"given":"Kazunao","family":"Hayashi","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology and Hepatology, Graduate School of Medical and Dental Sciences, Niigata University, 1-757 Aasahimachi-Dori, Chuo-ku, Niigata 951-8520, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9135-3092","authenticated-orcid":false,"given":"Hiroteru","family":"Kamimura","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology and Hepatology, Graduate School of Medical and Dental Sciences, Niigata University, 1-757 Aasahimachi-Dori, Chuo-ku, Niigata 951-8520, 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University School of Medicine, 30-1 Oyaguchi Kamicho, Itabashi-ku, Tokyo 173-8610, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0827-0964","authenticated-orcid":false,"given":"Hiroaki","family":"Okamoto","sequence":"additional","affiliation":[{"name":"Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, 3311-1 Yakushiji, Shimotsuke 329-0498, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5439-635X","authenticated-orcid":false,"given":"Shuji","family":"Terai","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology and Hepatology, Graduate School of Medical and Dental Sciences, Niigata University, 1-757 Aasahimachi-Dori, Chuo-ku, Niigata 951-8520, 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Rep."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"100505","DOI":"10.1016\/j.jfp.2025.100505","article-title":"Investigation of Two Outbreaks of Hepatitis A Virus Infections Linked to Fresh and Frozen Strawberries Imported from Mexico\u20142022\u20132023","volume":"88","author":"McClure","year":"2025","journal-title":"J. Food Prot."},{"key":"ref_3","first-page":"19","article-title":"Hepatitis A outbreak among men who have sex with men, Shinjuku, Japan, 2018","volume":"16","author":"Itaki","year":"2025","journal-title":"West. Pac. Surveill. Response J."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1038\/s41572-023-00461-2","article-title":"Hepatitis A virus infection","volume":"9","author":"Feng","year":"2023","journal-title":"Nat. Rev. Dis. Primers"},{"key":"ref_5","unstructured":"Los Angels Times (2025, October 24). California. Hepatitis A Outbreak Declared in L.A. County. \u2018We Really Have to Get Ahead of This\u2019. Available online: https:\/\/www.latimes.com\/california\/story\/2025-05-05\/hepatitis-a-outbreak-declared-in-la-county."},{"key":"ref_6","unstructured":"European Centre for Disease Prevention and Control (2025, October 24). ECDC Releases Risk Assessment with Actions Needed to Address Spike in Hepatitis A Cases. Available online: https:\/\/www.ecdc.europa.eu\/en\/news-events\/ecdc-releases-risk-assessment-actions-needed-address-spike-hepatitis-cases."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"S148","DOI":"10.1016\/0264-410X(92)90572-2","article-title":"Inactivated hepatitis A vaccine: Active and passive immunoprophylaxis in chimpanzees","volume":"10","author":"Purcell","year":"1992","journal-title":"Vaccine"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"4282","DOI":"10.1002\/j.1460-2075.1996.tb00803.x","article-title":"Identification of a surface glycoprotein on African green monkey kidney cells as a receptor for hepatitis A virus","volume":"15","author":"Kaplan","year":"1996","journal-title":"EMBO J."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"108113","DOI":"10.1016\/j.ijid.2025.108113","article-title":"Hepatitis A breakthrough infections despite vaccination\u2014A systematic review and meta-analysis","volume":"161","author":"Schnyder","year":"2025","journal-title":"Int. J. Infect. Dis."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1366","DOI":"10.1681\/ASN.V1061366","article-title":"Newer immunosuppressive drugs: A review","volume":"10","author":"Gummert","year":"1999","journal-title":"J. Am. Soc. Nephrol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"3791","DOI":"10.3748\/wjg.v11.i24.3791","article-title":"Prolonged acute hepatitis A mimicking autoimmune hepatitis","volume":"11","author":"Mikata","year":"2005","journal-title":"World J. Gastroenterol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"2381","DOI":"10.1001\/jama.2010.1658","article-title":"Mycophenolate mofetil vs azathioprine for remission maintenance in antineutrophil cytoplasmic antibody-associated vasculitis: A randomized controlled trial","volume":"304","author":"Hiemstra","year":"2010","journal-title":"JAMA"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1111\/ajt.16139","article-title":"The Fourth International Workshop on Clinical Transplant Tolerance","volume":"21","author":"Issa","year":"2021","journal-title":"Am. J. Transplant."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Di Maira, T., Little, E.C., and Berenguer, M. (2020). Immunosuppression in liver transplant. Best. Pract. Res. Clin. Gastroenterol., 46\u201347.","DOI":"10.1016\/j.bpg.2020.101681"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"2183","DOI":"10.1099\/0022-1317-83-9-2183","article-title":"Replication of a hepatitis A virus replicon detected by genetic recombination in vivo","volume":"83","author":"Kusov","year":"2002","journal-title":"J. Gen. Virol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"908","DOI":"10.1016\/j.bbrc.2015.02.058","article-title":"The JAK2 inhibitor AZD1480 inhibits hepatitis A virus replication in Huh7 cells","volume":"458","author":"Jiang","year":"2015","journal-title":"Biochem. Biophys. Res. Commun."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Kanda, T., Sasaki-Tanaka, R., Abe, H., Yokoo, T., Sakamaki, A., Hayashi, K., Kamimura, H., Tsuchiya, A., Masuzaki, R., and Kogure, H. (2025). Zinc Acetate Inhibits Hepatitis A Virus Replication: Possible Treatment for Patients with Type A Acute-on-Chronic Liver Failure. Pathogens, 14.","DOI":"10.3390\/pathogens14090882"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"212","DOI":"10.1186\/1743-422X-7-212","article-title":"Inhibitory effects on HAV IRES-mediated translation and replication by a combination of amantadine and interferon-alpha","volume":"7","author":"Yang","year":"2010","journal-title":"Virol. J."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"4633","DOI":"10.1128\/JVI.80.9.4633-4639.2006","article-title":"Generation of infectious hepatitis C virus in immortalized human hepatocytes","volume":"80","author":"Kanda","year":"2006","journal-title":"J. Virol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1002\/hep.1840220107","article-title":"Effect of immunosuppressive and antiviral agents on hepatitis B virus replication in vitro","volume":"22","author":"McMillan","year":"1995","journal-title":"Hepatology"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"397","DOI":"10.1002\/hep.27847","article-title":"Novel perspectives for hepatitis A virus therapy revealed by comparative analysis of hepatitis C virus and hepatitis A virus RNA replication","volume":"62","author":"Harak","year":"2015","journal-title":"Hepatology"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Rios-Usuga, C., Martinez-Gutierrez, M., and Ruiz-Saenz, J. (2024). Antiviral Potential of Azathioprine and Its Derivative 6- Mercaptopurine: A Narrative Literature Review. Pharmaceuticals, 17.","DOI":"10.3390\/ph17020174"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1111\/j.1365-2125.2007.02985.x","article-title":"IMPDH activity in thiopurine-treated patients with inflammatory bowel disease\u2013relation to TPMT activity and metabolite concentrations","volume":"65","author":"Haglund","year":"2008","journal-title":"Br. J. Clin. Pharmacol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"3042","DOI":"10.1073\/pnas.75.7.3042","article-title":"Adenosine kinase initiates the major route of ribavirin activation in a cultured human cell line","volume":"75","author":"Willis","year":"1978","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_25","first-page":"1682","article-title":"Effects of cyclosporine, azathioprine, mizoribine, and prednisolone on replication of human cytomegalovirus","volume":"22","author":"Shiraki","year":"1990","journal-title":"Transplant. Proc."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1007\/BF01310762","article-title":"Immunosuppressive dose of azathioprine inhibits replication of human cytomegalovirus in vitro","volume":"117","author":"Shiraki","year":"1991","journal-title":"Arch. Virol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"358","DOI":"10.1002\/j.1552-4604.1990.tb03606.x","article-title":"Azathioprine metabolism: Pharmacokinetics of 6-mercaptopurine, 6-thiouric acid and 6-thioguanine nucleotides in renal transplant patients","volume":"30","author":"Chan","year":"1990","journal-title":"J. Clin. Pharmacol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1611","DOI":"10.2169\/internalmedicine.4261-19","article-title":"Rare Genotype of His\/His in NUDT15 Codon 139 and Thiopurine-associated Adverse Events in a Case of Ulcerative Colitis","volume":"59","author":"Tomiyoshi","year":"2020","journal-title":"Intern. Med."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1759720X20947296","DOI":"10.1177\/1759720X20947296","article-title":"Oral disease-modifying antirheumatic drugs and immunosuppressants with antiviral potential, including SARS-CoV-2 infection: A review","volume":"12","author":"Tsai","year":"2020","journal-title":"Ther. Adv. Musculoskelet. Dis."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"823","DOI":"10.1097\/00126334-200407010-00009","article-title":"Effect of mycophenolate mofetil on immune response and plasma and lymphatic tissue viral load during and after interruption of highly active antiretroviral therapy for patients with chronic HIV infection: A randomized pilot study","volume":"36","author":"Plana","year":"2004","journal-title":"J. Acquir. Immune Defic. Syndr."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1807","DOI":"10.1099\/jgv.0.000512","article-title":"Mycophenolic acid, an immunomodulator, has potent and broad-spectrum in vitro antiviral activity against pandemic, seasonal and avian influenza viruses affecting humans","volume":"97","author":"To","year":"2016","journal-title":"J. Gen. Virol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"658","DOI":"10.1038\/nature03434","article-title":"Loss of cyclophilin D reveals a critical role for mitochondrial permeability transition in cell death","volume":"434","author":"Baines","year":"2005","journal-title":"Nature"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"4154","DOI":"10.1016\/j.jmb.2016.08.001","article-title":"A Novel In Vitro CypD-Mediated p53 Aggregation Assay Suggests a Model for Mitochondrial Permeability Transition by Chaperone Systems","volume":"428","author":"Lebedev","year":"2016","journal-title":"J. Mol. Biol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1282","DOI":"10.1053\/jhep.2003.50449","article-title":"Cyclosporin A suppresses replication of hepatitis C virus genome in cultured hepatocytes","volume":"38","author":"Watashi","year":"2003","journal-title":"Hepatology"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1031","DOI":"10.1053\/j.gastro.2005.06.031","article-title":"Suppression of hepatitis C virus replication by cyclosporin a is mediated by blockade of cyclophilins","volume":"129","author":"Nakagawa","year":"2005","journal-title":"Gastroenterology"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1016\/S1665-2681(19)31878-2","article-title":"Autoimmune hepatitis induced by the prolonged hepatitis A virus infection","volume":"7","author":"Tabak","year":"2008","journal-title":"Ann. Hepatol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"e0064622","DOI":"10.1128\/jvi.00646-22","article-title":"Amantadine and Rimantadine Inhibit Hepatitis A Virus Replication through the Induction of Autophagy","volume":"96","author":"Shibata","year":"2022","journal-title":"J. Virol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"223","DOI":"10.1111\/j.1600-0676.1989.tb00403.x","article-title":"Prolonged IgM antibodies and histopathological evidence of chronicity in hepatitis A","volume":"9","author":"McDonald","year":"1989","journal-title":"Liver"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"1318","DOI":"10.1002\/jmv.21822","article-title":"Atypical manifestations of hepatitis A infection: A prospective, multicenter study in Korea","volume":"82","author":"Jung","year":"2010","journal-title":"J. Med. Virol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1111\/hepr.13983","article-title":"Recent advances in hepatitis A virus research and clinical practice guidelines for hepatitis A virus infection in Japan","volume":"54","author":"Kanda","year":"2024","journal-title":"Hepatol. Res."}],"container-title":["Pathogens"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-0817\/15\/3\/249\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T10:53:26Z","timestamp":1772103206000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-0817\/15\/3\/249"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,2,26]]},"references-count":40,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2026,3]]}},"alternative-id":["pathogens15030249"],"URL":"https:\/\/doi.org\/10.3390\/pathogens15030249","relation":{},"ISSN":["2076-0817"],"issn-type":[{"value":"2076-0817","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2,26]]}}}