This review focuses on current approaches to understanding the immunopathogenesis of human T cell lymphotropic virus (HTLV) type I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) based on newly developed molecular and immunologic techniques that have been adapted to studies of HTLV-I proviral load, HTLV-I mRNA, and HTLV-I tax-specific CD8 T cells. These methods enable researchers t...

BACKGROUND Human T-cell lymphotropic virus type 1 (HTLV-1) screening of blood and organ donors is not mandatory in Germany because of its low prevalence (about 7/100 000). An HTLV-1 transmission event caused by a multiple organ donor was investigated. Validity of diagnostic procedures and HTLV-1 disease association in immunosuppressed organ recipients were analyzed. METHODS Two screening immu...

OBJECTIVE Th1 activation based on a high HTLV-I proviral load is one of the characteristic immunological abnormalities in the peripheral blood lymphocytes of patients with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). To clarify the cause of this abnormality with the potential to be one of the therapeutic targets, we analyzed the involvement of interleukin-2 (IL-2)/IL-2 r...

Human T-lymphotropic virus type 1 (HTLV-1), the etiological agent of adult T-cell leukemia, encodes unique regulatory and accessory proteins in the pX region of the provirus, including the open reading frame II product p13(II). p13(II) localizes to mitochondria, binds farnesyl pyrophosphate synthetase, an enzyme involved in posttranslational farnesylation of Ras, and alters Ras-dependent cell s...

Patients with human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) typically have a high HTLV-1 proviral load in peripheral blood mononuclear cells and abundant, activated HTLV-1-specific cytotoxic T lymphocytes (CTLs). No effective treatment for HAM/TSP has been described so far. We report a 10-fold reduction in viral DNA for five patients wi...

The extent of human T-cell leukemia/lymphoma virus type II (HTLV-II) infection and its rate of spread have been difficult to determine owing to the serological cross-reactivity between HTLV-I and HTLV-II. The present study overcame this problem by directly detecting type-specific proviral sequences by means of the polymerase chain reaction (PCR) and liquid hybridization. Screening was performed...

OBJECTIVE Few studies have specifically examined proviral load (PVL) and clonal evolution of human T-lymphotropic virus type 1 (HTLV-1)-infected cells in vertically infected children. METHODS Sequential samples (from ages 1 to 16 years) from 3 HTLV-1-infected children (cases A, B and C) in the Jamaica Mother Infant Cohort Study were analyzed for their PVL and clonal expansion of HTLV-1-infect...

BACKGROUND Human T-Lymphotropic Virus type 1 (HTLV-1) is endemic among people of Melanesian descent in Papua New Guinea, Solomon Islands and Vanuatu, and in Indigenous populations from Central Australia. Molecular studies revealed that these Australo-Melanesian strains constitute the highly divergent HTLV-1c subtype. New Caledonia is a French overseas territory located in the Southwest Pacific ...

INTRODUCTION To date there has been no statistical evaluation of the profiles of immunoglobulin classes and viral replication as variables in the study of HTLV-1 infection and circulation among families in virus-endemic areas of Colombia. OBJECTIVE To evaluate the correlation of several immunological and molecular characteristics with the transmission and circulation of HTLV-1 among families ...