{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T13:38:24Z","timestamp":1785418704564,"version":"3.56.0"},"reference-count":39,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2026,7,4]],"date-time":"2026-07-04T00:00:00Z","timestamp":1783123200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Health"},{"id":[{"id":"https:\/\/ror.org\/00789fa95","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Human endogenous retroviruses (HERVs) originate from ancient retroviral integration into the primate germline. Although most are defective proviruses, the most recently endogenized groups, like the HERV-K family, retain intact ORFs encoding retroviral proteins. HERVs usually remain transcriptionally silent, yet this status is reversible. Multiple HIV-HERV interactions, mainly mediated by the HIV Tat protein, lead to HERV transcription and protein production. The present study investigates HERV-K transcription in particular of Human MMTV-like (HML) group-2 and 6 in peripheral blood of people with HIV (PWH). Using different experimental approaches\u2014such as single-cell and plasma transcriptomics-, we found that HERV-K transcripts may be detected during both acute and chronic phases of the infection, with HML-6 showing higher expression compared to HML-2, predominantly within myeloid cells. Effective combined antiretroviral therapy (cART) was able to significantly reduce HML-6 transcription, regardless of whether the treatment was initiated in the acute or late chronic phases of HIV infection. Notably, chronic infections showed higher HML-6 transcript levels compared to acute infections in both na\u00efve and successfully cART-treated subjects, potentially associated with persistent immune dysregulation observed in chronic HIV infection, although a direct causal role of HML-6 expression remains to be established.<\/jats:p>","DOI":"10.3390\/ijms27136025","type":"journal-article","created":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T13:43:14Z","timestamp":1783345394000},"page":"6025","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Expression of Human Endogenous Retroviruses in Peripheral Blood of Acute and Chronically HIV-Infected Subjects and Effect of Antiretroviral Therapy"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-0558-0610","authenticated-orcid":false,"given":"Elisabetta","family":"Lazzari","sequence":"first","affiliation":[{"name":"Laboratory of 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Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4233-0839","authenticated-orcid":false,"given":"Daniele","family":"Pietrucci","sequence":"additional","affiliation":[{"name":"Department for Innovation in Biological, Agro-Food and Forest Systems\u2014DIBAF, University of Tuscia, 01100 Viterbo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3574-6027","authenticated-orcid":false,"given":"Daniele Maria","family":"Papetti","sequence":"additional","affiliation":[{"name":"Department of Informatics, Systems and Communication, University of Milano-Bicocca, 20126 Milan, Italy"},{"name":"Bicocca Bioinformatics Biostatistics and Bioimaging B4 Center, Department of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2975-8611","authenticated-orcid":false,"given":"Lavinia","family":"Fabeni","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, National Institute for Infectious Diseases Lazzaro Spallanzani IRCCS, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-8975-0089","authenticated-orcid":false,"given":"Flavia","family":"Smoquina","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, National Institute for Infectious Diseases Lazzaro Spallanzani IRCCS, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0331-2627","authenticated-orcid":false,"given":"Giulia","family":"Berno","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, National Institute for Infectious Diseases Lazzaro Spallanzani IRCCS, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3954-5679","authenticated-orcid":false,"given":"Federica","family":"Forbici","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, National Institute for Infectious Diseases Lazzaro Spallanzani IRCCS, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0240-7504","authenticated-orcid":false,"given":"Valentina","family":"Mazzotta","sequence":"additional","affiliation":[{"name":"Clinical Department, National Institute for Infectious Diseases Lazzaro Spallanzani IRCCS, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6351-2623","authenticated-orcid":false,"given":"Roberta","family":"Gagliardini","sequence":"additional","affiliation":[{"name":"Clinical Department, National Institute for Infectious Diseases Lazzaro Spallanzani IRCCS, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2121-4684","authenticated-orcid":false,"given":"Andrea","family":"Antinori","sequence":"additional","affiliation":[{"name":"Clinical Department, National Institute for Infectious Diseases Lazzaro Spallanzani IRCCS, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3901-6926","authenticated-orcid":false,"given":"Giovanni","family":"Chillemi","sequence":"additional","affiliation":[{"name":"Bioinformatics Research Unit in Infectious Diseases, National Institute for Infectious Diseases Lazzaro Spallanzani IRCCS, 00149 Rome, Italy"},{"name":"Department of Experimental Medicine, University of Rome \u201cTor Vergata\u201d, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7489-5271","authenticated-orcid":false,"given":"Fabrizio","family":"Maggi","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, National Institute for Infectious Diseases Lazzaro Spallanzani IRCCS, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4154-2434","authenticated-orcid":false,"given":"Isabella","family":"Abbate","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, National Institute for Infectious Diseases Lazzaro Spallanzani IRCCS, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e70452","DOI":"10.1002\/mco2.70452","article-title":"Human Endogenous Retroviruses and 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