title: Anti-HTLV-1 tax antibody and tax-specific cytotoxic T lymphocyte are associated with a reduction in HTLV-1 proviral load in asymptomatic carriers.
abstract: 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.
authors.affiliation: Department of Hematology and Immunology, Kagoshima University Hospital, Kagoshima, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Akimoto
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Kozako
authors.forename: Takashi
authors.initials: T
authors.lastname: Sawada
authors.forename: Kakushi
authors.initials: K
authors.lastname: Matsushita
authors.forename: Atsuo
authors.initials: A
authors.lastname: Ozaki
authors.forename: Heiichiro
authors.initials: H
authors.lastname: Hamada
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kawada
authors.forename: Makoto
authors.initials: M
authors.lastname: Yoshimitsu
authors.forename: Masahito
authors.initials: M
authors.lastname: Tokunaga
authors.forename: Koichi
authors.initials: K
authors.lastname: Haraguchi
authors.forename: Kimiharu
authors.initials: K
authors.lastname: Uozumi
authors.forename: Naomichi
authors.initials: N
authors.lastname: Arima
authors.forename: Chuwa
authors.initials: C
authors.lastname: Tei
mesh_terms: 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
chemical_list: D016356:Gene Products, tax; D015481:HTLV-I Antibodies; D010446:Peptide Fragments