{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,20]],"date-time":"2026-09-20T16:39:07Z","timestamp":1789922347889,"version":"4.0.1"},"reference-count":37,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,4,22]],"date-time":"2025-04-22T00:00:00Z","timestamp":1745280000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia (FCT)","doi-asserted-by":"publisher","award":["GHTM-UID\/04413\/2020"],"award-info":[{"award-number":["GHTM-UID\/04413\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia (FCT)","doi-asserted-by":"publisher","award":["LA-REAL\u2013LA\/P\/0117\/2020"],"award-info":[{"award-number":["LA-REAL\u2013LA\/P\/0117\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Crimean\u2013Congo hemorrhagic fever virus (CCHFV) causes severe or fatal infections in humans and is geographically widespread. The virus has coevolved with its tick vectors, establishing persistent infections critical to its transmission. This study explored the mechanisms underpinning these persistent infections, using tick cell lines and the Hazara virus (HAZV) as a biosafety level 2 (BSL-2) model for CCHFV. Initially, an RT-qPCR protocol was developed to detect HAZV in tick cells. The study then focused on the production of virus-derived DNA (vDNAs) by tick cells as a defensive response to infection. These vDNAs regulate viral particle production, enabling tick cells to maintain viability and establish persistent infections. The experiments characterized vDNAs production, viral titers, and subcellular localization, and they examined the effect of the reverse transcriptase inhibitor azidothymidine triphosphate (AZT). The results showed that all tested tick cell lines supported HAZV replication, achieving persistent infections without cytopathic effects. vDNAs was detected in both the cytoplasm and nucleus, and its formation was dependent on HAZV infection. Importantly, vDNAs presence was linked to infection persistence; cells treated with AZT exhibited a marked reduction in vDNAs production and an associated increase in viral particle production, which correlated with higher cell death. These findings underscore the critical role of vDNAs in balancing viral replication and promoting long-term cell survival in tick cells, highlighting their importance in the coevolution of tick-borne viruses and their vectors.<\/jats:p>","DOI":"10.3390\/v17050591","type":"journal-article","created":{"date-parts":[[2025,4,22]],"date-time":"2025-04-22T20:24:52Z","timestamp":1745353492000},"page":"591","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Persistent Infections in Tick Cell Lines: The Role of Viral-Derived DNA Forms in Hazara Virus Replication and Cellular Survival"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0138-6999","authenticated-orcid":false,"given":"Eva","family":"Dias","sequence":"first","affiliation":[{"name":"Global Health and Tropical Medicine (GHTM), Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa, UNL, Rua da Junqueira 100, 1349-008 Lisboa, Portugal"},{"name":"Gulbenkian Institute for Molecular Medicine (GIMM), Avenida Professor Egas Moniz, 1649-028 Lisboa, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0375-4698","authenticated-orcid":false,"given":"Filipe","family":"Tomaz","sequence":"additional","affiliation":[{"name":"Global Health and Tropical Medicine (GHTM), Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa, UNL, Rua da Junqueira 100, 1349-008 Lisboa, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-6919-1209","authenticated-orcid":false,"given":"Silvia","family":"Fabi","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine, University of Padova, Via A. Gabelli 63, 35121 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5136-7406","authenticated-orcid":false,"given":"Cristiano","family":"Salata","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine, University of Padova, Via A. Gabelli 63, 35121 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4570-2060","authenticated-orcid":false,"given":"Ana","family":"Domingos","sequence":"additional","affiliation":[{"name":"Global Health and Tropical Medicine (GHTM), Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa, UNL, Rua da Junqueira 100, 1349-008 Lisboa, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5745-2153","authenticated-orcid":false,"given":"Gon\u00e7alo","family":"Seixas","sequence":"additional","affiliation":[{"name":"Global Health and Tropical Medicine (GHTM), Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa, UNL, Rua da Junqueira 100, 1349-008 Lisboa, Portugal"},{"name":"Gulbenkian Institute for Molecular Medicine (GIMM), Avenida Professor Egas Moniz, 1649-028 Lisboa, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"463","DOI":"10.1038\/s41579-023-00871-9","article-title":"Crimean\u2013Congo haemorrhagic fever virus","volume":"21","author":"Hawman","year":"2023","journal-title":"Nat. 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