title: In vitro virus propagation and high cellular responsiveness to the infected cells in patients with HTLV-I-associated myelopathy (HAM/TSP).
abstract: The reasons for the development of HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in certain infected individuals remain poorly understood, but the susceptibility should involve both viral factors and host conditions. To assess simultaneously both virus-induced activation of infected cells and the cellular response to virus producing cells, an analysis of fractionated peripheral blood lymphocytes obtained from patients with HAM/TSP (n = 15) were compared with those of asymptomatic HTLV-I carriers (n = 9) in an age-matched manner. The in vitro propagation of HTLV-I infection was evaluated as the spontaneous thymidine incorporation into CD4+ cells, and proliferative response of CD8+ cells against cultured and irradiated autologous CD4+ cells was employed to analyze the HTLV-I-induced cellular response. The comparative analysis using these two parameters demonstrated that HAM/TSP patients were characterized by the concomitance of a high inducibility of HTLV-I propagation and a high cellular responsiveness against HTLV-I as compared with asymptomatic HTLV-I carriers, suggesting the involvement of both of these factors in disease susceptibility. In addition, the coupled evaluation of these two in vitro phenomena may offer a better diagnostic hallmark for HTLV-I seropositive myelopathy cases with other known cause of myelopathy.
authors.affiliation: Third Department of Internal Medicine, Faculty of Medicine, Kagoshima University, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Machigashira
authors.forename: S
authors.initials: S
authors.lastname: Ijichi
authors.forename: M
authors.initials: M
authors.lastname: Nagai
authors.forename: Y
authors.initials: Y
authors.lastname: Yamano
authors.forename: W W
authors.initials: WW
authors.lastname: Hall
authors.forename: M
authors.initials: M
authors.lastname: Osame
mesh_terms: D000328:Adult; D000368:Aged; D000956:Antigens, Viral / Q000494:pharmacology; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000821:virology; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000821:virology; D002353:Carrier State / Q000821:virology; D002455:Cell Division / Q000187:drug effects / Q000276:immunology; D005260:Female; D015368:Human T-lymphotropic virus 1 / Q000254:growth & development*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015493:Paraparesis, Tropical Spastic / Q000276:immunology / Q000821:virology*
chemical_list: D000956:Antigens, Viral