{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,27]],"date-time":"2026-04-27T18:45:00Z","timestamp":1777315500799,"version":"3.51.4"},"reference-count":32,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,6,28]],"date-time":"2023-06-28T00:00:00Z","timestamp":1687910400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o Ci\u00eancia e Tecnologia","award":["UIDP\/04923\/2020"],"award-info":[{"award-number":["UIDP\/04923\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Torque teno virus (TTV) was recently identified as a potential biomarker for the degree of immunosuppression, and potentially as a predictor of rejection and infection in solid organ transplant patients. We evaluated TTV viral load in kidney transplant (KT) patients during the first year post-transplant to examine overall kinetics and their relationships with deleterious events, including episodes of infection and the formation of de novo donor-specific antibodies (DSAs). In a single-center, prospective observational cohort study, 81 KT patients were monitored at baseline, week 1, and month 1, 3, 6, 9 and 12, post-KT, and whenever required by clinical events. Kidney function, plasma TTV load, immunoglobulins and lymphocyte subpopulations were assessed at each time point. Twenty-six patients (32.1%) presented a total of 38 infection episodes post-KT. Induction immunosuppression with thymoglobulin, compared to basiliximab, was not associated with more infections (p = 0.8093). Patients with infectious events had lower T-cells (p = 0.0500), CD8+ T-cells (p = 0.0313) and B-cells (p = 0.0009) 1 month post-KT, compared to infection-free patients. Patients with infection also showed higher increases in TTV viral loads between week 1- month 1, post-KT, with TTV viral load variations &gt;2.65 log10 cp\/mL predicting the development of infectious events during the 12-month study period (p &lt; 0.0001; sensitivity 99.73%; specificity 83.67%). Patients who developed de novo DSAs had lower TTV DNA viral loads at month 12 after KT, compared to patients who did not develop DSA (3.7 vs. 5.3 log10 cp\/mL, p = 0.0023). Briefly, evaluating early TTV viremia is a promising strategy for defining infectious risk in the 1st year post-KT. The availability of standardized commercial real-time PCR assays is crucial to further validate this as an effective tool guiding immunosuppression prescription.<\/jats:p>","DOI":"10.3390\/v15071464","type":"journal-article","created":{"date-parts":[[2023,6,29]],"date-time":"2023-06-29T00:49:47Z","timestamp":1687999787000},"page":"1464","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Kinetics of Torque Teno Virus Viral Load Is Associated with Infection and De Novo Donor Specific Antibodies in the First Year after Kidney Transplantation: A Prospective Cohort Study"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2325-1817","authenticated-orcid":false,"given":"Sara","family":"Querido","sequence":"first","affiliation":[{"name":"Renal Transplantation Unit, Nephrology Department, Hospital de Santa Cruz, Centro Hospitalar de Lisboa Ocidental, 2790-134 Carnaxide, Portugal"},{"name":"Infection, Sepsis & Antibiotics Resistance Research Group, CHRC\u2014Comprehensive Health Research Center, NOVA Medical School, Faculdade de Ci\u00eancias M\u00e9dicas (NMS|FCM), Universidade NOVA de Lisboa, 1150-082 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0353-0421","authenticated-orcid":false,"given":"Catarina","family":"Martins","sequence":"additional","affiliation":[{"name":"Immune Dysregulation from Pregnancy to Adulthood Research Group, CHRC\u2014Comprehensive Health Research Center, NOVA Medical School, Faculdade de Ci\u00eancias M\u00e9dicas (NMS|FCM), Universidade NOVA de Lisboa, 1150-082 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3271-8255","authenticated-orcid":false,"given":"Perp\u00e9tua","family":"Gomes","sequence":"additional","affiliation":[{"name":"Laboratory of Clinical Microbiology and Molecular Biology, Department of Clinical Pathology, Centro Hospitalar de Lisboa Ocidental, 1349-019 Lisboa, Portugal"},{"name":"Centro de Investiga\u00e7\u00e3o Interdisciplinar Egas Moniz (CiiEM), IUEM, 2829-511 Almada, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1393-932X","authenticated-orcid":false,"given":"Maria Ana","family":"Pessanha","sequence":"additional","affiliation":[{"name":"Laboratory of Clinical Microbiology and Molecular Biology, Department of Clinical Pathology, Centro Hospitalar de Lisboa Ocidental, 1349-019 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7648-3294","authenticated-orcid":false,"given":"Maria Jorge","family":"Arroz","sequence":"additional","affiliation":[{"name":"Flow Cytometry Laboratory, Department of Clinical Pathology, Centro Hospitalar de Lisboa Ocidental, 1349-019 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3919-1070","authenticated-orcid":false,"given":"Teresa","family":"Adrag\u00e3o","sequence":"additional","affiliation":[{"name":"Renal Transplantation Unit, Nephrology Department, Hospital de Santa Cruz, Centro Hospitalar de Lisboa Ocidental, 2790-134 Carnaxide, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-0660-5168","authenticated-orcid":false,"given":"Ana","family":"Casqueiro","sequence":"additional","affiliation":[{"name":"Renal Transplantation Unit, Nephrology Department, Hospital de Santa Cruz, Centro Hospitalar de Lisboa Ocidental, 2790-134 Carnaxide, Portugal"}]},{"given":"Regina","family":"Oliveira","sequence":"additional","affiliation":[{"name":"Renal Transplantation Unit, Nephrology Department, Hospital de Santa Cruz, Centro Hospitalar de Lisboa Ocidental, 2790-134 Carnaxide, Portugal"}]},{"given":"In\u00eas","family":"Costa","sequence":"additional","affiliation":[{"name":"Laboratory of Clinical Microbiology and Molecular Biology, Department of Clinical Pathology, Centro Hospitalar de Lisboa Ocidental, 1349-019 Lisboa, Portugal"}]},{"given":"Jorge","family":"Azinheira","sequence":"additional","affiliation":[{"name":"Laboratory of Biochemistry, Department of Clinical Pathology, Centro Hospitalar de Lisboa Ocidental, 1349-019 Lisboa, Portugal"}]},{"given":"Paulo","family":"Paix\u00e3o","sequence":"additional","affiliation":[{"name":"Infection, Sepsis & Antibiotics Resistance Research Group, CHRC\u2014Comprehensive Health Research Center, NOVA Medical School, Faculdade de Ci\u00eancias M\u00e9dicas (NMS|FCM), Universidade NOVA de Lisboa, 1150-082 Lisboa, Portugal"}]},{"given":"Andr\u00e9","family":"Weigert","sequence":"additional","affiliation":[{"name":"Renal Transplantation Unit, Nephrology Department, Hospital de Santa Cruz, Centro Hospitalar de Lisboa Ocidental, 2790-134 Carnaxide, Portugal"},{"name":"Pharmacology and Neurosciences Institute, Faculdade de Medicina, Universidade de Lisboa, 1649-004 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1225","DOI":"10.1080\/17425255.2017.1395413","article-title":"Pharmacokinetic considerations 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Int."}],"container-title":["Viruses"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1999-4915\/15\/7\/1464\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T20:02:33Z","timestamp":1760126553000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1999-4915\/15\/7\/1464"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,6,28]]},"references-count":32,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2023,7]]}},"alternative-id":["v15071464"],"URL":"https:\/\/doi.org\/10.3390\/v15071464","relation":{},"ISSN":["1999-4915"],"issn-type":[{"value":"1999-4915","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,6,28]]}}}