title: Humoral immune response to HTLV-1 basic leucine zipper factor (HBZ) in HTLV-1-infected individuals.
abstract: BACKGROUND
  Human T cell lymphotropic virus type 1 (HTLV-1) infection can lead to development of adult T cell leukemia/lymphoma (ATL) or HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in a subset of infected subjects. HTLV-1 basic leucine zipper factor (HBZ) gene has a critical role in HTLV-1 infectivity and the development of ATL and HAM/TSP. However, little is known about the immune response against HBZ in HTLV-1-infected individuals. In this study, we examined antibody responses against HBZ in serum/plasma samples from 436 subjects including HTLV-1 seronegative donors, asymptomatic carriers (AC), ATL, and HAM/TSP patients using the luciferase immunoprecipitation system.
  
  
  RESULTS
  Immunoreactivity against HBZ was detected in subsets of all HTLV-1-infected individuals but the test did not discriminate between AC, ATL and HAM/TSP. However, the frequency of detection of HBZ-specific antibodies in the serum of ATL patients with the chronic subtype was higher than in ATL patients with the lymphomatous subtype. Antibody responses against HBZ were also detected in cerebrospinal fluid of HAM/TSP patients with anti-HBZ in serum. Antibody responses against HBZ did not correlate with proviral load and HBZ mRNA expression in HAM/TSP patients, but the presence of an HBZ-specific response was associated with reduced CD4+ T cell activation in HAM/TSP patients. Moreover, HBZ-specific antibody inhibited lymphoproliferation in the PBMC of HAM/TSP patients.
  
  
  CONCLUSIONS
  This is the first report demonstrating humoral immune response against HBZ associated with HTLV-I infection. Thus, a humoral immune response against HBZ might play a role in HTLV-1 infection.
authors: Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA.
authors: Yoshimi
authors: Y
authors: Enose-Akahata
authors: Anna
authors: A
authors: Abrams
authors: Raya
authors: R
authors: Massoud
authors: Izabela
authors: I
authors: Bialuk
authors: Kory R
authors: KR
authors: Johnson
authors: Patrick L
authors: PL
authors: Green
authors: Elizabeth M
authors: EM
authors: Maloney
authors: Steven
authors: S
authors: Jacobson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood / Q000134:cerebrospinal fluid / Q000276:immunology; D050976:Basic-Leucine Zipper Transcription Factors / Q000276:immunology*; D005260:Female; D015686:Gene Products, env / Q000276:immunology; D015683:Gene Products, gag / Q000276:immunology; D016356:Gene Products, tax / Q000276:immunology; D015490:HTLV-I Infections / Q000276:immunology*; D015368:Human T-lymphotropic virus 1 / Q000276:immunology*; D006801:Humans; D056724:Immunity, Humoral; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012191:Retroviridae Proteins; D013601:T-Lymphocytes / Q000276:immunology; D014764:Viral Proteins / Q000276:immunology*; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D050976:Basic-Leucine Zipper Transcription Factors; D015686:Gene Products, env; D015683:Gene Products, gag; D016356:Gene Products, tax; C479751:HBZ protein, human T-cell leukemia virus type I; D012191:Retroviridae Proteins; D014764:Viral Proteins