The role of human T-cell leukemia virus type II (HTLV-II) in human lymphoproliferative and hematopoietic abnormalities in which the retrovirus can be isolated is still elusive. Here we show that the C344 T-cell-derived lymphotropic HTLV-II type IIa Mo strain acts directly on CD34+ hematopoietic precursors by rescuing them from apoptosis induced by interleukin-3 (IL-3) deprivation. This effect i...

Although most patients with the cutaneous T-cell lymphoma, mycosis fungoides (MF), are seronegative for human T-cell lymphotropic virus-I or -II (HTLV-I/II) when tested by assays that measure only antibodies to the viral structural proteins, the majority of such patients harbor HTLV-I-related pol and tax proviral sequences that encode proteins not included in routinely used serologic tests. Tax...

Blood samples from native Indians in the Kararao village (Kayapo), were analysed using serological and molecular methods to characterize infection and analyse transmission of HTLV-II. Specific reactivity was observed in 3/26 individuals, of which two samples were from a mother and child. RFLP analysis of the pX and env regions confirmed HTLV-II infection. Nucleotide sequence of the 5' LTR segme...

In this report, we describe a flow cytometric analysis of HTLV-I specific binding to fresh and cultured cells on a single cell basis. This assay uses rhodamine hydrocarbon tagged, purified HTLV-I virions according to the procedure originally described for avian retroviruses. Successful HTLV-I transmission was detected by analysis of integrated HTLV-I DNA, virion-associated reverse transcriptase...

Human T-lymphotropic virus type 1 (HTLV-1) is a persistent CD4+ T-lymphotropic retrovirus. Most HTLV-1-infected individuals remain asymptomatic, but a proportion develop adult T cell leukemia or inflammatory disease. It is not fully understood how HTLV-1 persists despite a strong immune response or what determines the risk of HTLV-1-associated diseases. Until recently, it has been difficult to ...

Abstract Background Human T-lymphotropic virus 1 (HTLV-1) is etiologically associated with the chronic inflammatory neurodegenerative disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) Annexin A1 (AnxA1) an anti-inflammatory protein proposed neuroprotective and anti-neuroinflammatory functions. We hypothesized that ANXA1 gene expression may be dysregulated in HTLV-1-inf...

Methods: Of 1340 present and former blood donors examined at enrollment, 1213 (90.5%) were re-examined after approximately 2 years, including 136 HTLV-I– and 337 HTLV-II–seropositive subjects and 740 demographically stratified HTLV-seronegative subjects. All subjects were seronegative for human immunodeficiency virus. Odds ratios (ORs) for incident disease outcomes were adjusted for covariates,...

The human retroviruses HIV-1 and HTLV-1/HTLV-2 share similar routes of transmission but cause significantly different diseases. In this review we have outlined the immune mediated mechanisms by which HTLVs affect HIV-1 disease in co-infected hosts. During co-infection with HIV-1, HTLV-2 modulates the cellular microenvironment favoring its own viability and inhibiting HIV-1 progression. This is ...

The human T-cell leukemia viruses HTLV-I and HTLV-II are unique among the transforming retroviruses of vertebrates in their ability to transform human T cells in vitro and in their close association with human malignancies (T-cell lymphomas and leukemia). Their genomes are relatively simple, containing the genes gag, pol, env, and a 3' region termed "X." This 3' region may be responsible for th...