title: Human T-lymphotropic virus type I (HTLV-I)-specific CD8+ cells accumulate in the lungs of patients infected with HTLV-I with pulmonary involvement.
abstract: Pulmonary involvement has been identified in human T-lymphotropic virus type I (HTLV-I) carriers and patients with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). However, the relationship between HTLV-I infection and lung disease is poorly understood. The occurrence of HTLV-I-specific immune responses in the lungs of patients infected with HTLV-I with pulmonary involvement was investigated. The frequency of HTLV-I-specific CD8+ cells and the amount of HTLV-I proviral DNA were determined in bronchoalveolar lavage fluid cells and peripheral blood mononuclear cells (PBMCs) from five patients with HAM/TSP and one HTLV-I carrier who had pulmonary involvement. HTLV-I-specific CD8+ cells were detected by flow cytometry using human leukocyte antigen/antigen complex multimers. The analysis of bronchoalveolar lavage fluid revealed lymphocytosis in five of six patients. HTLV-I provirus was detected in the bronchoalveolar lavage fluid cells of all patients, and the proviral load in these cells was comparable to that in PBMCs. The frequency of HTLV-I-specific CD8+ cells in the bronchoalveolar lavage fluid cells was 5.1 times higher than that in PBMCs. Immunohistochemically, clusters formed by HTLV-I-specific CD8+ cells were detected in lung tissue by in situ tetramer staining. No samples were available from patients infected with HTLV-I without lung disorders. Whether accumulation of CD8+ cells is specific to patients with pulmonary involvement remains unclear. These results indicate that HTLV-I-specific CD8+ cells accumulate and HTLV-I-infected cells exist in the lungs of patients infected with HTLV-I with pulmonary involvement.
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawabata
authors.forename: Ikkou
authors.initials: I
authors.lastname: Higashimoto
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takashima
authors.forename: Shuji
authors.initials: S
authors.lastname: Izumo
authors.forename: Ryuji
authors.initials: R
authors.lastname: Kubota
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001769:Blood / Q000276:immunology / Q000821:virology; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000821:virology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002353:Carrier State / Q000276:immunology / Q000821:virology; D005260:Female; D015490:HTLV-I Infections / Q000276:immunology* / Q000821:virology; D015368:Human T-lymphotropic virus 1 / Q000276:immunology*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000821:virology; D008168:Lung / Q000276:immunology* / Q000821:virology*; D008171:Lung Diseases / Q000276:immunology* / Q000821:virology; D008875:Middle Aged; D011533:Proviruses / Q000302:isolation & purification; D019562:Viral Load