Anti-HTLV-1 tax antibody and tax-specific cytotoxic T lymphocyte are associated with a reduction in HTLV-1 proviral load in asymptomatic carriers.
Previous studies have suggested that higher anti-human T-lymphotropic virus 1 (HTLV-1) antibody titer and lower anti-HTLV-1 Tax antibody reactivity are risk factors for adult T-cell leukemia/lymphoma. In the present study, we analyzed the relationships between these factors and clarified their significance. Forty-five carriers were examined for anti-HTLV-1 and anti-Tax antibody by ELISA. In addition, 43 of the 45 carriers with HLA-A*0201 and/or A*2402 were examined for frequency of Tax-specific cytotoxic T lymphocytes (CTLs) using HTLV-1/HLA tetramers, and 44 were examined for proviral load by real-time PCR. The relationships between these factors were analyzed statistically. The frequencies of Tax11-19 and Tax301-309-specific CTLs were significantly higher in the anti-Tax antibody-positive group as compared with the antibody-negative group (P = 0.002 and 0.033, respectively). Anti-HTLV-1 antibody titer had a positive correlation with proviral load (P = 0.019), whereas anti-Tax antibody did not show a significant correlation. Higher frequencies of both Tax11-19 and Tax301-309-specific CTLs are related to a reduction in proviral load (P = 0.017 and 0.015, respectively). Synergistic interactions of humoral and cellular immunity against Tax protein were demonstrated in HTLV-1 carriers. Tax-specific CTL may reduce HTLV-1 proviral load to prevent asymptomatic carriers from developing adult T-cell leukemia/lymphoma.
Akimoto
Masaki
M
Department of Hematology and Immunology, Kagoshima University Hospital, Kagoshima, Japan.
Kozako
Tomohiro
T
Sawada
Takashi
T
Matsushita
Kakushi
K
Ozaki
Atsuo
A
Hamada
Heiichiro
H
Kawada
Hideaki
H
Yoshimitsu
Makoto
M
Tokunaga
Masahito
M
Haraguchi
Koichi
K
Uozumi
Kimiharu
K
Arima
Naomichi
N
Tei
Chuwa
C
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D002353:Carrier State / Q000276:immunology* / Q000821:virology*; D005260:Female; D016356:Gene Products, tax / Q000235:genetics / Q000276:immunology*; D015481:HTLV-I Antibodies / Q000097:blood*; D015490:HTLV-I Infections / Q000276:immunology* / Q000821:virology*; D015368:Human T-lymphotropic virus 1 / Q000276:immunology / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000235:genetics / Q000276:immunology; D011533:Proviruses / Q000276:immunology / Q000302:isolation & purification; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
D016356:Gene Products, tax; D015481:HTLV-I Antibodies; D010446:Peptide Fragments