{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T02:27:43Z","timestamp":1785464863203,"version":"3.56.0"},"reference-count":44,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,24]],"date-time":"2023-01-24T00:00:00Z","timestamp":1674518400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Human T-cell leukemia virus type 1 (HTLV-1) is the causal agent of adult T-cell leukemia\/lymphoma and HTLV-1-associated myelopathy\/tropical spastic paraparesis. Its tropism is known to be broad in cultured cell lines, while in vivo data support a more selective transmission toward CD4+ T cells and the limited targeting of other hematopoietic cell types. An essential condition for HTLV-1 infection is cell-to-cell contact, to which both virological synapse and viral biofilm have been suggested to strongly contribute. As cell lines and animal models each present their own limitations in studying HTLV-1 replication, we have explored the use of an ex vivo model based on the secondary lymphoid tonsillar tissue. HIV-1 luciferase-expressing pseudotyped viruses bearing the HTLV-1 envelope protein at their surface were first shown to recapitulate the wide spectrum of infectivity of HTLV-1 toward various cell lines. Tonsil fragments were next exposed to pseudotyped viruses and shown to be reproducibly infected. Infection by HTLV-1 Env-pseudotyped viruses was blocked by different anti-gp46 antibodies, unlike infection by HIV-1 virions. The dose-dependent infection revealed a gradual increase in luciferase activity, which was again sensitive to anti-gp46 antibodies. Overall, these results suggest that the ex vivo tonsil model represents a reliable alternative for studying HTLV-1 replication and potentially viral latency, as well as early clonal formation.<\/jats:p>","DOI":"10.3390\/pathogens12020182","type":"journal-article","created":{"date-parts":[[2023,1,25]],"date-time":"2023-01-25T03:23:49Z","timestamp":1674617029000},"page":"182","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Infection of the Ex Vivo Tonsil Model by HTLV-1 Envelope-Pseudotyped Viruses"],"prefix":"10.3390","volume":"12","author":[{"given":"M\u00e9lanie","family":"Langlois","sequence":"first","affiliation":[{"name":"Axe des Maladies Infectieuses et Immunitaires, Centre de Recherche du Centre Hospitalier, Universitaire de Qu\u00e9bec-Universit\u00e9 Laval, Qu\u00e9bec, QC G1V 4G2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Salim","family":"Bounou","sequence":"additional","affiliation":[{"name":"Axe des Maladies Infectieuses et Immunitaires, Centre de Recherche du Centre Hospitalier, Universitaire de Qu\u00e9bec-Universit\u00e9 Laval, Qu\u00e9bec, QC G1V 4G2, Canada"},{"name":"Euromed Research Center, Faculty of Pharmacy, Universit\u00e9 EUROMED de F\u00e8s, Fez 30000, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michel J.","family":"Tremblay","sequence":"additional","affiliation":[{"name":"Axe des Maladies Infectieuses et Immunitaires, Centre de Recherche du Centre Hospitalier, Universitaire de Qu\u00e9bec-Universit\u00e9 Laval, Qu\u00e9bec, QC G1V 4G2, Canada"},{"name":"D\u00e9partement de Microbiologie-Infectiologie et Immunologie, Facult\u00e9 de M\u00e9decine, Universit\u00e9 Laval, Qu\u00e9bec, QC G1V 0A6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benoit","family":"Barbeau","sequence":"additional","affiliation":[{"name":"D\u00e9partement de Sciences Biologiques, Universit\u00e9 du Qu\u00e9bec \u00e0 Montr\u00e9al, Montr\u00e9al, QC H3C 3P8, Canada"},{"name":"R\u00e9seau Intersectoriel de Recherche en Sant\u00e9 de l\u2019Universit\u00e9 du Qu\u00e9bec (RISUQ), Montr\u00e9al, QC H2X 1E3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7415","DOI":"10.1073\/pnas.77.12.7415","article-title":"Detection and isolation of type C retrovirus particles from fresh and cultured lymphocytes of a patient with cutaneous T-cell lymphoma","volume":"77","author":"Poiesz","year":"1980","journal-title":"Proc. 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