Expression of human T lymphotropic virus type 1 (HTLV-1) tax/rex gene in fresh bronchoalveolar lavage cells of HTLV-1-infected individuals

Clin Exp Immunol. 1994 May;96(2):193-201. doi: 10.1111/j.1365-2249.1994.tb06541.x.


Accumulating evidence has suggested the involvement of HTLV-1 in the inflammatory lesions of various organs, including the lung. However, the causal relationship between HTLV-1 and inflammatory responses in the organs remains to be elucidated. In order to evaluate the expression of HTLV-1 and its effects in the lung, we examined the expression of mRNA for the HTLV-1 tax/rex gene in fresh bronchoalveolar lavage cells (BALC) and peripheral blood mononuclear cells (PBMC) of 23 seropositive individuals, including six patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), by use of an improved method of reverse transcription-polymerase chain reaction (RT-PCR). The tax/rex mRNA was more frequently detected in BALC than in PBMC. All the HAM/TSP patients and eight of 17 carriers without neurological symptoms showed the expression of tax/rex mRNA in the BALC. IgM class antibodies to HTLV-1 were preferentially detected in sera of the tax/rex mRNA-positive individuals. The detection of tax/rex mRNA correlated closely with the presence of lymphocytosis accompanied by an elevated proportion of IL-2 receptor-bearing T cells in the BALC. Our findings indicate the crucial role of viral expression in the inflammatory response in the lung in HTLV-1-infected individuals.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Base Sequence
  • Bronchoalveolar Lavage Fluid / cytology
  • Bronchoalveolar Lavage Fluid / microbiology*
  • Carrier State / microbiology
  • Deltaretrovirus Antibodies / blood
  • Female
  • Genes, pX / genetics*
  • HTLV-I Infections / immunology
  • HTLV-I Infections / microbiology*
  • Humans
  • Lung Diseases / microbiology
  • Male
  • Middle Aged
  • Molecular Sequence Data
  • Paraparesis, Tropical Spastic / microbiology
  • Polymerase Chain Reaction
  • RNA, Messenger / analysis*
  • Receptors, Interleukin-2 / analysis
  • T-Lymphocytes / pathology


  • Deltaretrovirus Antibodies
  • RNA, Messenger
  • Receptors, Interleukin-2