{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T12:28:10Z","timestamp":1789820890415,"version":"4.0.1"},"reference-count":0,"publisher":"National Academy of Sciences","issue":"6","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1992,3,15]]},"abstract":"<jats:p>A unique feature of both human T-cell leukemia virus type I (HTLV-I) carriers and subjects with HTLV-I-associated myelopathy\/tropical spastic paraparesis (HAM\/TSP), a chronic inflammatory disease of the nervous system, is the presence of large numbers of activated T cells that spontaneously proliferate in vitro. We have investigated the mechanisms of T-cell activation by HTLV-I in freshly isolated blood T cells and in naturally infected T-cell clones obtained by direct single-cell cloning from patients with HAM\/TSP. Both CD4+ and CD8+ HTLV-I-infected T-cell clones showed the unusual ability to proliferate in the absence of exogenous interleukin 2 (IL-2). Nevertheless, HTLV-I-infected clones were not transformed, as they required periodic restimulation with phytohemagglutinin and feeder cells for long-term growth. Irradiated or fixed HTLV-I-infected clones were found to induce the proliferation of blood T cells when cocultured, which we refer to as THTLV-1-T cell activation. This THTLV-1-T cell-mediated activation was blocked by monoclonal antibodies (mAbs) against CD2\/lymphocyte function-associated molecule 3 (LFA-3), LFA-1\/intercellular cell-adhesion molecule (ICAM), and the IL-2 receptor but not by mAbs against class I or class II major histocompatibility complex molecules, HTLV-I gp46, or a high-titer HAM\/TSP serum. Spontaneous proliferation of blood T cells from HAM\/TSP patients could also be inhibited by mAbs to CD2\/LFA-3, LFA-1\/ICAM and to the IL-2 receptor (CD25). These results show at the clonal level that HTLV-I infection induces T-cell activation and that such activated T cells can in turn stimulate noninfected T cells by cognate THTLV-1-T cell interactions involving the CD2 pathway.<\/jats:p>","DOI":"10.1073\/pnas.89.6.2110","type":"journal-article","created":{"date-parts":[[2006,5,31]],"date-time":"2006-05-31T08:18:24Z","timestamp":1149063504000},"page":"2110-2114","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":67,"title":["T-cell activation by autologous human T-cell leukemia virus type I-infected T-cell clones."],"prefix":"10.1073","volume":"89","author":[{"given":"K W","family":"Wucherpfennig","sequence":"first","affiliation":[{"name":"Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P","family":"H\u00f6llsberg","sequence":"additional","affiliation":[{"name":"Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J H","family":"Richardson","sequence":"additional","affiliation":[{"name":"Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D","family":"Benjamin","sequence":"additional","affiliation":[{"name":"Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D A","family":"Hafler","sequence":"additional","affiliation":[{"name":"Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[1992,3,15]]},"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.89.6.2110","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T13:40:56Z","timestamp":1649857256000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.89.6.2110"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1992,3,15]]},"references-count":0,"journal-issue":{"issue":"6","published-print":{"date-parts":[[1992,3,15]]}},"alternative-id":["10.1073\/pnas.89.6.2110"],"URL":"https:\/\/doi.org\/10.1073\/pnas.89.6.2110","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1992,3,15]]},"assertion":[{"value":"1992-03-15","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}