Human T-cell leukemia virus type 1 (HTLV-1) but not HTLV-2 is associated with adult T-cell leukemia. We found that HTLV-2 Tax2 protein stimulated reporter gene expression regulated by the interleukin (IL)-2 promoter through the nuclear factor of activated T cells (NFAT) in a human T-cell line (Jurkat). However, the activity of HTLV-1 Tax1 was minimal in this system. T-cell lines immortalized by...

Synthetic peptides representing the immunodominant structural motifs of the envelope region of human T-lymphotropic virus types I (HTLV-I) (Env-1(191-214) and Env-5(242-257)) and II (HTLV-II) (Env-20(85-102 and Env-2(187-209)) were used to develop an enzyme immunoassay that could discriminate between HTLV-I and HTLV-II. Serum specimens from individuals whose infections were confirmed and typed ...

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-cell lymphotropic virus type I (HTLV-I) associated adult T-cell leukemia/lymphoma (ATLL) occurs endemically in southwestern Japan, the Caribbean, and West Africa, but occurs sporadically in most of the rest of the world. However, because ATLL and non-HTLV-I associated T-cell neoplasms share overlapping clinicopathologic features, the prevalence of ATLL in nonendemic regions is unknown. ...

OBJECTIVES Human T-lymphotropic virus (HTLV)-1 causes T-cell leukaemia and myelopathy. Together with HTLV-2, it is endemic in some African nations. Seroprevalence data from Malawi are scarce, with no reports on associated disease incidence. HTLV seroprevalence and type were tested in 418 healthy mothers from Malawi. In addition, we tested the sera of 534 children to investigate mother-to-child ...

BACKGROUND HTLV-1 and HTLV-2 are retroviruses linked etiologically to various human diseases, and both of them can be transmitted by vertical route, sexual intercourse, blood transfusion and intravenous drug use. Recently, some HTLV-infected cases have been reported and this virus is mainly present in the Southeast coastal areas in China, but has not been studied for the people in Central China...

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 ...

The complete nucleotide sequence of a human T-cell lymphotropic virus type II isolate (HTLV-II-Gu) from an Italian injecting drug user was obtained, representing the first entire sequence of a European HTLV-II isolate. The HTLV-II-Gu genome was more similar to the HTLV-IIb-NRA isolate (98.4%) and HTLV-IIb-G12 (98.2%) than to HTLV-IIa-Mo (95.2%). The classification of HTLV-II-Gu as subtype IIb w...

To determine the molecular genetic relationship between Melanesian strains of human T-lymphotropic virus type I (HTLV-I) and cosmopolitan prototype HTLV-I, we amplified by PCR, then cloned, and sequenced a 522-base-pair region of the HTLV-I env gene in DNA extracted from uncultured (fresh) and cultured peripheral blood mononuclear cells obtained from six seropositive Melanesian Papua New Guinea...