{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T23:20:36Z","timestamp":1789600836466,"version":"build-2803163510"},"reference-count":45,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,7,25]],"date-time":"2021-07-25T00:00:00Z","timestamp":1627171200000},"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>Approximately 25% of HIV-infected patients are co-infected with HCV. Notably, the burden of HCV infection (e.g., viral persistence, viral load, or HCV-related liver symptoms) is more pronounced in the presence of HIV co-infection. However, to date, the underlying immune mechanisms accounting for accelerated disease progression in HIV\/HCV-coinfected individuals have not been described in sufficient detail. We hypothesized that regulatory T cells (Treg) bearing potent immunosuppressive capacities could not only play a substantial role in the pathogenesis of HCV\/HIV coinfection but also modulate the response to the standard anti-viral therapy. Materials and Methods: To this end, we studied alterations in frequencies of Treg cells in correlation with other Treg-related and virus-related parameters in both HCV and HCV\/HIV-infected patients subjected to standard pegIFN-\u03b1\/RBV therapy. Results: Notably, we found that pegIFN-\u03b1\/RBV therapy significantly increased levels of Treg cells in HCV-infected but not in HIV\/HCV-coinfected individuals. Furthermore, HIV\/HCV-coinfection was demonstrated to inhibit expansion of regulatory T cells during anti-viral treatment; thus, it might probably be responsible for viral persistence and HCV-related liver damage. Conclusions: Therapy with pegIFN-\u03b1\/RBV demonstrated a significant effect on regulatory T cells in the course of HIV and\/or HCV infection indicating a crucial role in the anti-viral immune response.<\/jats:p>","DOI":"10.3390\/v13081448","type":"journal-article","created":{"date-parts":[[2021,7,25]],"date-time":"2021-07-25T22:07:00Z","timestamp":1627250820000},"page":"1448","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Effects of Pegylated Interferon Alpha and Ribavirin (pegIFN-\u03b1\/RBV) Therapeutic Approach on Regulatory T Cells in HCV-Monoinfected and HCV\/HIV-Coinfected Patients"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6828-6397","authenticated-orcid":false,"given":"Kamil","family":"Grubczak","sequence":"first","affiliation":[{"name":"Department of Regenerative Medicine and Immune Regulation, Medical University of Bialystok, 15-269 Bia\u0142ystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Grzeszczuk","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Neuroinfections, Medical University of Bialystok, 15-540 Bialystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monika","family":"Groth","sequence":"additional","affiliation":[{"name":"Department of Allergology and Internal Medicine, Medical University of Bialystok, 15-089 Bialystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Hryniewicz","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation, Medical University of Bialystok, 15-089 Bialystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6820-6273","authenticated-orcid":false,"given":"Anna","family":"Kretowska-Grunwald","sequence":"additional","affiliation":[{"name":"Department of Regenerative Medicine and Immune Regulation, Medical University of Bialystok, 15-269 Bia\u0142ystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3394-1635","authenticated-orcid":false,"given":"Robert","family":"Flisiak","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Hepatology, Medical University of Bialystok, 15-540 Bialystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcin","family":"Moniuszko","sequence":"additional","affiliation":[{"name":"Department of Regenerative Medicine and Immune Regulation, Medical University of Bialystok, 15-269 Bia\u0142ystok, Poland"},{"name":"Department of Allergology and Internal Medicine, Medical University of Bialystok, 15-089 Bialystok, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1016\/j.antiviral.2009.10.021","article-title":"Viral hepatitis and HIV co-infection","volume":"85","author":"Soriano","year":"2010","journal-title":"Antivir. 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