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


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.
deShazo
R D
RD
Tulane/Louisiana State University AIDS Clinical Trials Group, New Orleans.
Chadha
N
N
Morgan
J E
JE
Shorty
V J
VJ
Rangan
S R
SR
Kalyanaraman
V S
VS
Hyslop
N
N
Chapman
Y
Y
O'Dea
S
S
D000328:Adult; D000911:Antibodies, Monoclonal; D005260:Female; D015483:HIV Antibodies / Q000032:analysis; D015481:HTLV-I Antibodies / Q000032:analysis; D015490:HTLV-I Infections / Q000276:immunology*; D006801:Humans; D007694:Killer Cells, Natural / Q000145:classification; D008145:Louisiana; D008213:Lymphocyte Activation; D008297:Male; D008691:Methadone / Q000627:therapeutic use*; D008875:Middle Aged; D019966:Substance-Related Disorders / Q000534:rehabilitation*; D013601:T-Lymphocytes / Q000145:classification*; D006377:T-Lymphocytes, Helper-Inducer / Q000145:classification; D050378:T-Lymphocytes, Regulatory / Q000145:classification
D000911:Antibodies, Monoclonal; D015483:HIV Antibodies; D015481:HTLV-I Antibodies; D008691:Methadone