{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T22:12:04Z","timestamp":1775081524750,"version":"3.50.1"},"reference-count":45,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2024,11,22]],"date-time":"2024-11-22T00:00:00Z","timestamp":1732233600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:sec><jats:title>Introduction<\/jats:title><jats:p>TLR7 detects the presence of single-stranded RNA (ssRNA) viruses, including human T-lymphotropic virus 1 (HTLV-1), and triggers antiviral and inflammatory responses that are responsible for infection control. Genetic variations in the <jats:italic>TLR7<\/jats:italic> gene may alter cytokine production and influence the course of HTLV-1 infection. In the present study, the associations of <jats:italic>TLR7<\/jats:italic> gene polymorphisms with HTLV-1-related symptoms, receptor expression levels, IFN-\u03b1 and TNF-\u03b1 levels and the proviral load were investigated.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>Blood samples from 159 individuals with HTLV-1 infection (66 with inflammatory diseases and 93 asymptomatic individuals) and 159 controls were collected. The genotyping of polymorphisms, TLR7 gene expression analysis and the quantification of the proviral load were performed by real-time PCR, and cytokine measurement was performed by enzyme-linked immunosorbent assay (ELISA).<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>Carriers of the polymorphic allele for <jats:italic>TLR7<\/jats:italic> rs179008 (A\/T) had lower levels of IFN-\u03b1, while carriers of the polymorphic allele for <jats:italic>TLR7<\/jats:italic> rs3853839 (C\/G) had higher levels of TLR7 and IFN-\u03b1 expression. The polymorphisms were not associated with symptoms of diseases related to HTLV-1 infection. The combination of A\/G alleles for the <jats:italic>TLR7<\/jats:italic> rs179008 (A\/T) and <jats:italic>TLR7<\/jats:italic> rs3853839 (C\/G) polymorphisms was associated with increased IFN-\u03b1 levels and a decreased proviral load.<\/jats:p><\/jats:sec><jats:sec><jats:title>Discussion<\/jats:title><jats:p>Although the polymorphisms did not influence the presence of symptoms of diseases caused by HTLV-1, carriers of the wild-type alleles for <jats:italic>TLR7<\/jats:italic> rs179008 (A\/T) and the polymorphism for <jats:italic>TLR7<\/jats:italic> rs3853839 (C\/G) appears to have a stronger antiviral response and increased infection control.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fimmu.2024.1462352","type":"journal-article","created":{"date-parts":[[2024,11,22]],"date-time":"2024-11-22T05:13:03Z","timestamp":1732252383000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":7,"title":["TLR7 rs179008 (A\/T) and TLR7 rs3853839 (C\/G) polymorphisms are associated with variations in IFN-\u03b1 levels in HTLV-1 infection"],"prefix":"10.3389","volume":"15","author":[{"given":"Emmanuelle Giuliana Mendes","family":"Santana","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fabiane dos Santos","family":"Ferreira","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wandrey Roberto dos Santos","family":"Brito","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Felipe Teixeira","family":"Lopes","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aline Cecy Rocha","family":"de Lima","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gabriel dos Santos 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