A third type of primate T-lymphotropic virus, PTLV-L, with STLV-PH969 as a prototype, has recently been isolated from an African baboon (Papio hamadryas). Classification of this virus has been based on partial sequence analysis of cDNA from a virus-producing cell line, PH969. We obtained the complete nucleotide sequence of this virus with a proviral genome of 8,916 bp. All major genes, homologo...

HTLV-1 Tax expression exerts an inhibitory effect on the Foxp3 transcription factor in CD4+CD25+ T-regulatory cells (Treg). For a better understanding of the role of Tax mRNA in the gene expression of cellular markers we measured Tax, Foxp3, CTLA4, GITR, TGF-β, and IL-10 mRNA in Treg cells of 50 patients with human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic para...

HTLV-I is a retrovirus now identified as the etiologic agent of two diverse disease processes: ATLL, an aggressive T-cell malignancy; and TSP/HAM, a chronic progressive myelopathy. Transmission can occur horizontally through blood transfusions, IV drug abuse and sexual intercourse. Vertical transmission may also occur. Available diagnostic modalities are serologic in nature and include the EIA ...

When the human T cell lymphotropic virus (HTLV) is integrated with the host cell genome (provirus), its proviral DNA is a replication marker. Proviral load appears to be an important factor in the development of diseases related to these retroviruses. In this study, a methodology for absolute quantification of the HTLV-1 and HTLV-2 proviral load using real-time PCR was developed. Fifty-three bl...

The susceptibility to Fas-mediated apoptosis was evaluated in seven T-cell lines (two infected with HTLV-2, one with HTLV-1, and four HTLV-free) as well as in Jurkat cells transfected with a Tax-2 expressing vector. Fas-mediated apoptosis was significantly reduced in the HTLV-1- and HTLV-2-infected lines in comparison with the HTLV-free lines regardless of the surface expression of Fas antigen ...

We investigated the tempo and mode of evolution of the primate T-lymphotropic viruses (PTLVs). Several different models of nucleotide substitution were tested on a general phylogenetic tree obtained using the 20 full-genome HTLV/STLV sequences available. The likelihood ratio test showed that the Tamura and Nei model with discrete gamma-distributed rates among sites is the best-fitting substitut...

Human T-lymphotropic virus type I (HTLV-I), a causative agent of adult T-cell leukemia, (ATL) is transmitted from mother to child. ATL cells originate from the CD4 subset of peripheral T cells. The main route of mother-to-child transmission is postnatal breast-feeding. Refraining from breast-feeding or limiting the duration of breast-feeding can reduce the risk of mother-to-child transmission. ...

The human T-lymphotropic virus type III (HTLV-III) is the primary cause of the acquired immunodeficiency syndrome (AIDS) and related disorders (ARC). Prior studies have reported that nearly all symptomatic patients with AIDS or ARC manifest antibody to HTLV-III. This observation has engendered efforts to screen for HTLV-III, especially prior to blood donation, with assays for antibody to HTLV-I...

BACKGROUND Retroviruses of human T-lymphotropic viruses (HTLV-1 and HTLV-2) have been demonstrated to be endemic in the north-eastern region of Iran. This study was aimed to determine the HTLV-1 and HTLV-2 prevalence among healthy individuals in Neyshabur City during 2010-2014. METHODS A total of 8054 blood samples were collected from healthy participants in Neyshabur, North-Eastern Iran. The...