{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,27]],"date-time":"2025-11-27T13:50:09Z","timestamp":1764251409309,"version":"build-2065373602"},"reference-count":53,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2015,10,28]],"date-time":"2015-10-28T00:00:00Z","timestamp":1445990400000},"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>Background: indeterminate Western blot (WB) patterns are a major concern for diagnosis of human T-cell lymphotropic virus type 1 (HTLV-1) infection, even in non-endemic areas. Objectives: (a) to define the prevalence of indeterminate WB among different populations from Argentina; (b) to evaluate if low proviral load (PVL) is associated with indeterminate WB profiles; and (c) to describe mutations in LTR and tax sequence of these cases. Results: Among 2031 samples, 294 were reactive by screening. Of them, 48 (16.3%) were WB indeterminate and of those 15 (31.3%) were PCR+. Quantitative real-time PCR (qPCR) was performed to 52 HTLV-1+ samples, classified as Group 1 (G1): 25 WB+ samples from individuals with pathologies; Group 2 (G2): 18 WB+ samples from asymptomatic carriers (AC); and Group 3 (G3): 9 seroindeterminate samples from AC. Median PVL was 4.78, 2.38, and 0.15 HTLV-1 copies\/100 PBMCs, respectively; a significant difference (p=0.003) was observed. Age and sex were associated with PVL in G1 and G2, respectively. Mutations in the distal and central regions of Tax Responsive Elements (TRE) 1 and 2 of G3 were observed, though not associated with PVL.The 8403A&gt;G mutation of the distal region, previously related to high PVL, was absent in G3 but present in 50% of WB+ samples (p = 0.03). Conclusions: indeterminateWBresults confirmed later as HTLV-1 positive may be associated with low PVL levels. Mutations in LTR and tax are described; their functional relevance remains to be determined.<\/jats:p>","DOI":"10.3390\/v7112897","type":"journal-article","created":{"date-parts":[[2015,10,28]],"date-time":"2015-10-28T13:43:01Z","timestamp":1446039781000},"page":"5643-5658","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Low Proviral Load is Associated with Indeterminate Western Blot Patterns in Human T-Cell Lymphotropic Virus Type 1 Infected Individuals: Could Punctual Mutations be Related?"],"prefix":"10.3390","volume":"7","author":[{"given":"Camila","family":"C\u00e1nepa","sequence":"first","affiliation":[{"name":"Instituto de Investigaciones Biom\u00e9dicas en Retrovirus y SIDA, UBA-CONICET, Paraguay 2155, piso 11, C1121ABG, CABA, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jimena","family":"Salido","sequence":"additional","affiliation":[{"name":"Instituto de Investigaciones Biom\u00e9dicas en Retrovirus y SIDA, UBA-CONICET, Paraguay 2155, piso 11, C1121ABG, CABA, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mat\u00edas","family":"Ruggieri","sequence":"additional","affiliation":[{"name":"Instituto de Investigaciones Biom\u00e9dicas en Retrovirus y SIDA, UBA-CONICET, Paraguay 2155, piso 11, C1121ABG, CABA, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sindy","family":"Fraile","sequence":"additional","affiliation":[{"name":"Instituto de Investigaciones Biom\u00e9dicas en Retrovirus y SIDA, UBA-CONICET, Paraguay 2155, piso 11, C1121ABG, CABA, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gabriela","family":"Pataccini","sequence":"additional","affiliation":[{"name":"Instituto de Investigaciones Biom\u00e9dicas en Retrovirus y SIDA, UBA-CONICET, Paraguay 2155, piso 11, C1121ABG, CABA, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carolina","family":"Berini","sequence":"additional","affiliation":[{"name":"Instituto de Investigaciones Biom\u00e9dicas en Retrovirus y SIDA, UBA-CONICET, Paraguay 2155, piso 11, C1121ABG, CABA, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mirna","family":"Biglione","sequence":"additional","affiliation":[{"name":"Instituto de Investigaciones Biom\u00e9dicas en Retrovirus y SIDA, UBA-CONICET, Paraguay 2155, piso 11, C1121ABG, CABA, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,10,28]]},"reference":[{"doi-asserted-by":"crossref","unstructured":"Gessain, A., and Cassar, O. 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