Immunologic assessment of a cluster of asymptomatic HTLV-I-infected individuals in New Orleans

Am J Med. 1989 Jan;86(1):65-70. doi: 10.1016/0002-9343(89)90231-3.


Purpose: Although clusters of individuals infected with the human T-cell lymphotrophic virus type I (HTLV-I) have been identified in the United States, no systematic evaluation of the immunologic status of these persons has been reported. We therefore studied a group of 11 HTLV-I-infected former intravenous drug abusers who were long-term participants in a methadone maintenance program in New Orleans, Louisiana, to determine the effects of HTLV-I and chronic opiate use on immunity.

Patients and methods: Mitogenic responses and results of serologic studies, cell phenotype analysis, and cytotoxicity assays were compared to those in two other HTLV-I seronegative groups: a similar group of 17 methadone users and 15 healthy age-, sex-, and race-matched control subjects. All study participants were seronegative for human immunodeficiency virus type 1.

Results: Percentages and numbers of total T lymphocytes (CD2+,CD3+), T-suppressor/cytotoxic lymphocytes (CD8+), cytotoxic lymphocytes (Leu7+, Leu11+, NKH-1+) and B lymphocytes (B4+) were similar among the study groups. Although percentages and numbers of total T-helper lymphocytes (CD4+) were also similar among the groups, HTLV-I-infected subjects had higher percentages and proportions of helper/inducer cells (CD4:4B4+) than did HTLV-I seronegative methadone users. Both methadone using groups had decreased percentages and numbers of suppressor/inducer T lymphocytes (CD4:2H4+). Major histocompatibility complex unrestricted T-cell cytotoxicity (lectin-dependent cellular cytotoxicity), natural killer cell function, and mitogenic responses to the T-cell mitogen phytohemagglutin were similar among the three study groups. Pokeweed mitogen responses were severely depressed in the HTLV-I-infected population.

Conclusions: We conclude that HTLV-I infection is associated with abnormalities in T-cell-dependent B-cell proliferative responses. Furthermore, both long-term methadone use and HTLV-I infection are associated with abnormalities in the distribution of CD4+ cell subpopulations. The increase in the helper/inducer and T-cell cell populations and decrease in the pokeweed mitogenic response noted in HTLV-I-infected subjects appear to be markers for infection with this retrovirus.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Antibodies, Monoclonal
  • Female
  • HIV Antibodies / analysis
  • HTLV-I Antibodies / analysis
  • HTLV-I Infections / immunology*
  • Humans
  • Killer Cells, Natural / classification
  • Louisiana
  • Lymphocyte Activation
  • Male
  • Methadone / therapeutic use*
  • Middle Aged
  • Substance-Related Disorders / rehabilitation*
  • T-Lymphocytes / classification*
  • T-Lymphocytes, Helper-Inducer / classification
  • T-Lymphocytes, Regulatory / classification


  • Antibodies, Monoclonal
  • HIV Antibodies
  • HTLV-I Antibodies
  • Methadone