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HTLV1 proviral load in peripheral blood mononuclear cells quantified in 100 HAM/TSP patients: A marker of disease progression

Department of Neurology and UMR 433 INSERM, Pierre Zobda-Quitman Hospital, Fort-de-France, Martinique, French West Indies.
Journal of the Neurological Sciences (Impact Factor: 2.24). 01/2005; 237(1):53-59. DOI: 10.1016/j.jns.2005.05.010

ABSTRACT A high proviral load of human T cell lymphotropic virus type 1 (HTLV-1) in peripheral blood mononuclear cells (PBMCs) has been reported in patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The aim of the present study was to investigate the role of HTLV-1 proviral load in PBMCs (expressed as the number of copies per 106 PBMCs) in HAM/TSP disease course. One hundred consecutive HAM/TSP patients were recruited and assigned on the basis of the disability score and disease duration to either a rapid (n=38) or a slow (n=62) progression group. Thirty-four asymptomatic HTLV-1 carriers were also included. HTLV-1 proviral load was quantified in all HAM/TSP patients and asymptomatic subjects. The mean HTLV-1 proviral load was 6-fold lower in asymptomatic carriers than in HAM/TSP patients (18,224±24,811 vs. 107,905±96,651, p

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