{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,16]],"date-time":"2026-05-16T14:40:41Z","timestamp":1778942441198,"version":"3.51.4"},"reference-count":30,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,17]],"date-time":"2021-01-17T00:00:00Z","timestamp":1610841600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Quinacrine (Qx), a molecule used as an antimalarial, has shown anticancer, antiprion, and antiviral activity. The most relevant antiviral activities of Qx are related to its ability to raise pH in acidic organelles, diminishing viral enzymatic activity for viral cell entry, and its ability to bind to viral DNA and RNA. Moreover, Qx has been used as an immunomodulator in cutaneous lupus erythematosus and various rheumatological diseases, by inhibiting phospholipase A2 modulating the Th1\/Th2 response. The aim of this study was to evaluate the potential antiviral effect of Qx against denominated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Vero E6 cells. The cytotoxicity of Qx in Vero E6 cells was determined by the MTT assay. Afterwards, Vero E6 cells were infected with SARS-CoV-2 at different multiplicities of infections (MOIs) of 0.1 and 0.01 in the presence of Qx (0\u201330 \u00b5M) to determinate the half maximal effective concentration (EC50). After 48 h, the effect of Qx against SARS-CoV-2 was assessed by viral cytotoxicity and viral copy numbers, the last were determined by digital real-time RT-PCR (ddRT-PCR). Additionally, electron and confocal microscopy of Vero E6 cells infected and treated with Qx was studied. Our data show that Qx reduces SARS-CoV-2 virus replication and virus cytotoxicity, apparently by inhibition of viral ensemble, as observed by ultrastructural images, suggesting that Qx could be a potential drug for further clinical studies against coronavirus disease 2019 (COVID-19) infection.<\/jats:p>","DOI":"10.3390\/v13010121","type":"journal-article","created":{"date-parts":[[2021,1,21]],"date-time":"2021-01-21T02:36:05Z","timestamp":1611196565000},"page":"121","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Quinacrine, an Antimalarial Drug with Strong Activity Inhibiting SARS-CoV-2 Viral Replication In Vitro"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7046-0967","authenticated-orcid":false,"given":"M\u00f3nica","family":"Salas Rojas","sequence":"first","affiliation":[{"name":"Unidad de Investigaci\u00f3n M\u00e9dica en Inmunolog\u00eda, Unidad Medica de Alta Especialidad, Hospital de Pediatr\u00eda, Centro M\u00e9dico Nacional \u201cSiglo XXI\u201d, Instituto Mexicano del Seguro Social, Cuauht\u00e9moc 330, Mexico Ctiy 06720, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ra\u00fal","family":"Silva Garcia","sequence":"additional","affiliation":[{"name":"Unidad de Investigaci\u00f3n M\u00e9dica en Inmunolog\u00eda, Unidad Medica de Alta Especialidad, Hospital de Pediatr\u00eda, Centro M\u00e9dico Nacional \u201cSiglo XXI\u201d, Instituto Mexicano del Seguro Social, Cuauht\u00e9moc 330, Mexico Ctiy 06720, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Estela","family":"Bini","sequence":"additional","affiliation":[{"name":"Secci\u00f3n de Patolog\u00eda Experimental, Instituto Nacional de Ciencias M\u00e9dicas y Nutrici\u00f3n Salvador Zubir\u00e1n, Vasco de Quiroga 15, Mexico Ctiy 14080, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1451-8754","authenticated-orcid":false,"given":"Ver\u00f3nica","family":"P\u00e9rez de la Cruz","sequence":"additional","affiliation":[{"name":"Laboratorio de Neurobioqu\u00edmica y Conducta, Instituto Nacional de Neurolog\u00eda y Neurocirug\u00eda, Insurgentes sur 3877, Mexico Ctiy 14269, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8827-1670","authenticated-orcid":false,"given":"Juan Carlos","family":"Le\u00f3n Contreras","sequence":"additional","affiliation":[{"name":"Secci\u00f3n de Patolog\u00eda Experimental, Instituto Nacional de Ciencias M\u00e9dicas y Nutrici\u00f3n Salvador Zubir\u00e1n, Vasco de Quiroga 15, Mexico Ctiy 14080, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rogelio","family":"Hern\u00e1ndez Pando","sequence":"additional","affiliation":[{"name":"Secci\u00f3n de Patolog\u00eda Experimental, Instituto Nacional de Ciencias M\u00e9dicas y Nutrici\u00f3n Salvador Zubir\u00e1n, Vasco de Quiroga 15, Mexico Ctiy 14080, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1670-5879","authenticated-orcid":false,"given":"Fernando","family":"Bastida Gonzalez","sequence":"additional","affiliation":[{"name":"Laboratorio de Biolog\u00eda Molecular, Laboratorio Estatal de Salud P\u00fablica del Estado de Mexico, Estado de M\u00e9xico, Toluca 50130, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eduardo","family":"Davila-Gonzalez","sequence":"additional","affiliation":[{"name":"Laboratorio de Biolog\u00eda Molecular, Laboratorio Estatal de Salud P\u00fablica del Estado de Mexico, Estado de M\u00e9xico, Toluca 50130, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mario","family":"Orozco Morales","sequence":"additional","affiliation":[{"name":"Unidad Funcional de Oncolog\u00eda Tor\u00e1cica y Medicina Personalizada, Instituto Nacional de Cancerolog\u00eda, San Fernando 22, Mexico Ctiy 14080, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Armando","family":"Gamboa Dom\u00ednguez","sequence":"additional","affiliation":[{"name":"Departamento de Patolog\u00eda, Instituto Nacional de Ciencias M\u00e9dicas y Nutrici\u00f3n Salvador Zubir\u00e1n, Mexico Ctiy 14080, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Julio","family":"Sotelo","sequence":"additional","affiliation":[{"name":"Laboratorio de Neuroinmunolog\u00eda, Instituto Nacional de Neurolog\u00eda y Neurocirug\u00eda, Insurgentes sur 3877, Mexico Ctiy 14269, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1455-312X","authenticated-orcid":false,"given":"Benjam\u00edn","family":"Pineda","sequence":"additional","affiliation":[{"name":"Laboratorio de Neuroinmunolog\u00eda, Instituto Nacional de 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