CD4(+) T cells predominate in early lesions in the CNS in the inflammatory disease human lymphotropic T cell virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP), but the pathogenesis of the disease remains unclear and the HTLV-I-specific CD4(+) T cell response has been little studied. We quantified the IFN-gamma-producing HTLV-I-specific CD4(+) T cells, in patient...

Background: Perforin is known to be important in cytolytic activity mediated by natural killer (NK) cells.   Objective: To study the relationship between the efficiency of NK and lymphokine-activated killer (LAK) cells activity, and the expression of perforin and HLA class I molecules.   Methods: LAK cells were generated by in vitro culturing of human peripheral blood lymphocytes (PBLs) in the ...

Neurogenic bladder is common in patients with human T lymphotropic virus type 1 (HTLV-1)–associated myelopathy/tropical spastic paraparesis (HAM/TSP). Here, we describe isolated neurogenic bladder dysfunction in HTLV-1–infected individuals without HAM/TSP and show that HTLV-1 proviral load is higher in such patients than it is in asymptomatic carriers. We suggest that testing for HTLV-1 antibod...

Human T lymphotropic virus type 2 (HTLV-2) is characterized by a clinically asymptomatic persistent infection in the vast majority of infected individuals. In this study, we have characterized for the first time ex vivo specific CTL responses against the HTLV-2 Tax protein. We could detect CTL responses only against a single HLA-A*0201-restricted Tax2 epitope, comprising residues 11-19 (LLYGYPV...

BACKGROUND High HTLV-1 proviral load (PVL) is mainly found in infected individuals with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). However one third of asymptomatic carriers may have high PVL. This study aimed to evaluate the impact of PVL in the activation of T lymphocytes of asymptomatic individuals infected with HTLV-1. METHODS Membrane activation markers (CD25+, ...