title: Natural killer (NK) cells in HTLV-I-associated myelopathy/tropical spastic paraparesis-decrease in NK cell subset populations and activity in HTLV-I seropositive individuals.
abstract: We examined natural killer (NK) cell activity and NK cell subset populations in 18 patients with HTLV-I associated myelopathy (HAM)/tropical spastic paraparesis (TSP), ten HTLV-I seropositive asymptomatic carriers and 20 seronegative healthy controls. The NK cell activity was significantly decreased in HAM/TSP, compared with that in controls. The percentages of NK cell subsets, such as CD16+, CD11b+, CD56+, CD16+ CD56-, CD16-CD56+, CD16+CD8-, or CD16+CD3+ cells were significantly decreased in HAM/TSP patients. Of particular interest is that the percentage of CD16+CD3+ cells, which have a wide spectrum of cytotoxic properties commonly seen in NK, lymphokine activated killer (LAK) and antibody-dependent cellular-cytotoxic (ADCC) effector cells, was significantly decreased in HAM/TSP as compared to asymptomatic carriers as well as controls. The percentage of CD16+CD3+ cells correlated inversely with the value of spontaneous proliferation of peripheral blood lymphocytes (SPP), which is a characteristic change observed in HAM/TSP.
authors.affiliation: Department of Neurology, Kyushu University, Fukuoka, Japan.
authors.forename: F
authors.initials: F
authors.lastname: Yu
authors.forename: Y
authors.initials: Y
authors.lastname: Itoyama
authors.forename: K
authors.initials: K
authors.lastname: Fujihara
authors.forename: I
authors.initials: I
authors.lastname: Goto
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D015490:HTLV-I Infections / Q000276:immunology* / Q000473:pathology; D006801:Humans; D016130:Immunophenotyping; D007694:Killer Cells, Natural / Q000276:immunology* / Q000473:pathology; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D015493:Paraparesis, Tropical Spastic / Q000276:immunology* / Q000382:microbiology / Q000473:pathology