Comparative biology of human T-cell lymphotropic virus type 1 (HTLV-1) and HTLV-2.
HTLV-1 and HTLV-2 are highly related complex retroviruses that have been studied intensely for nearly three decades because of their association with neoplasia, neuropathology, and/or their capacity to transform primary human T lymphocytes. The study of HTLV also represents an attractive model that has allowed investigators to dissect the mechanism of various cellular processes, several of which may be critical steps in HTLV-mediated pathogenesis. Both HTLV-1 and HTLV-2 can efficiently immortalize and transform T lymphocytes in cell culture and persist in infected individuals or experimental animals. However, the clinical manifestations of these two viruses differ significantly. HTLV-1 is associated with adult T-cell leukemia (ATL) and a variety of immune-mediated disorders including the chronic neurological disease termed HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). In contrast, HTLV-2 is much less pathogenic with reports of only a few cases of variant hairy cell leukemia and neurological disease associated with infection. The limited number of individuals shown to harbor HTLV-2 in association with specific diseases has, to date, precluded convincing epidemiological demonstration of a definitive etiologic role of HTLV-2 in human disease. Therefore, it has become clear that comparative studies designed to elucidate the mechanisms by which HTLV-1 and HTLV-2 determine distinct outcomes are likely to provide fundamental insights into the initiation of multistep leukemogenesis.
Feuer
Gerold
G
Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse, New York 13210, USA.
Green
Patrick L
PL
D000818:Animals; D002453:Cell Cycle / Q000235:genetics; D002471:Cell Transformation, Neoplastic; D016356:Gene Products, tax / Q000378:metabolism; D015368:Human T-lymphotropic virus 1 / Q000472:pathogenicity / Q000502:physiology*; D015367:Human T-lymphotropic virus 2 / Q000472:pathogenicity / Q000502:physiology*; D006801:Humans; D016328:NF-kappa B / Q000378:metabolism; D013601:T-Lymphocytes / Q000821:virology
D016356:Gene Products, tax; D016328:NF-kappa B