Human T-lymphotropic virus type I-associated myelopathy and tax gene expression in CD4+ T lymphocytes

Ann Neurol. 1996 Jul;40(1):84-90. doi: 10.1002/ana.410400114.


Infection by human T-lymphotropic virus type I (HTLV-I) is associated with adult T-cell leukemia and a slowly progressive disease of the central nervous system (CNS), HTLV-I-associated myelopathy/tropical spastic paraparesis, characterized pathologically by inflammation and white matter degeneration in the spinal cord. One of the explanations for the tissue destruction is that HTLV-I infects cells in the CNS, or HTLV-I-infected CD4+ T lymphocytes enter the CNS, and this drives local expansion of virus-specific CD8+ cytotoxic T lymphocytes, which along with cytokines cause the pathological changes. Because both in the circulation and in the cerebrospinal fluid, CD8+ cytotoxic T lymphocytes are primarily reactive to the product of the HTLV-I tax gene, we sought evidence of expression of this gene within cells in the inflammatory lesions. After using double-label in situ hybridization techniques, we now report definitive localization of HTLV-I tax gene expression in CD4+ T lymphocytes in areas of inflammation and white matter destruction. These findings lend support to a hypothetical scheme of neuropathogenesis in which HTLV-I tax gene expression provokes and sustains an immunopathological process that progressively destroys myelin and axons in the spinal cord.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Base Sequence
  • Brain / pathology
  • Brain / virology
  • CD4-Positive T-Lymphocytes / metabolism*
  • CD4-Positive T-Lymphocytes / virology
  • Cells, Cultured
  • Culture Techniques
  • Female
  • Gene Expression
  • Genes, pX*
  • Humans
  • Immunohistochemistry
  • In Situ Hybridization
  • Leukemia, T-Cell / genetics
  • Leukemia, T-Cell / pathology
  • Leukemia, T-Cell / virology
  • Male
  • Molecular Sequence Data
  • Paraparesis, Tropical Spastic / genetics
  • Paraparesis, Tropical Spastic / pathology
  • Paraparesis, Tropical Spastic / virology*
  • RNA, Messenger / analysis
  • RNA, Viral / analysis
  • Spinal Cord / pathology
  • Spinal Cord / virology


  • RNA, Messenger
  • RNA, Viral