Human T-cell leukemia viruses: epidemiology, biology, and pathogenesis

Blood Rev. 1997 Jun;11(2):91-104. doi: 10.1016/s0268-960x(97)90015-1.


The human T-cell lymphotropic viruses type I and type II are closely related human retroviruses that have similar biological properties, genetic organization and tropism for T lymphocytes. Along with the simian T-cell lymphoma virus type I, they define the group of retroviruses known as the primate T-cell leukemia/lymphoma viruses. Initially identified in 1980, the human T-cell lymphotropic virus type I has been implicated as the etiologic agent of adult T-cell leukemia/lymphoma and of a degenerative neurologic disorder known as tropical spastic paraparesis or human T-cell lymphotropic virus type I-associated myelopathy. The intriguing link between human T-cell lymphotropic virus type, T-cell malignancy, and a totally unrelated and non-overlapping neurological disorder suggests divergent and unique pathogenetic mechanisms. This review will address the epidemiology, molecular biology, and pathogenesis of human T-cell leukemia viruses.

Publication types

  • Review

MeSH terms

  • Adult
  • Animals
  • Gene Products, rex / metabolism
  • Gene Products, tax / metabolism
  • HTLV-I Infections / epidemiology*
  • HTLV-I Infections / genetics
  • HTLV-I Infections / transmission
  • HTLV-II Infections / epidemiology*
  • HTLV-II Infections / genetics
  • HTLV-II Infections / transmission
  • Human T-lymphotropic virus 1 / genetics
  • Human T-lymphotropic virus 1 / pathogenicity*
  • Human T-lymphotropic virus 2 / genetics
  • Human T-lymphotropic virus 2 / pathogenicity*
  • Humans


  • Gene Products, rex
  • Gene Products, tax