Skip to main content

The plasticity of HTLV-1 infected CD4+CD25+CCR4+ T-cells through HTLV-1 tax in HAM/TSP

Recently, it has become increasingly clear that some committed effecter and regulatory T (Treg) cells are not stable, and the plasticity of committed T-cells may be related to autoimmunity and inflammatory disease. However, the environmental (extrinsic) molecules that allow for plasticity have not yet been clearly understood.

In Human T-lymphotropic virus type 1 (HTLV-1) associated myelopathy /tropical spastic paraparesis (HAM/TSP), the pathogenesis is known as HTLV-1 infected CD4+ T-cells triggered hyper immune response, which leads to chronic inflammation of the central nervous system. In our previous study, we demonstrated that the majority of CD4+CD25+CCR4+ T-cells were infected with HTLV-1 and that this T-cell subset was increased in HAM/TSP. Although CD4+CD25+CCR4+ T-cells of healthy condition include suppressive T cell subsets such as Treg and Th2, this T-cell subset becomes Th1-like cells with overproduction of IFN-γ in HAM/TSP patients (PLoS ONE 2009). Since HTLV-1 tax is known to up-regulate the expression of several proinflammatory cytokines, and importantly, the level of HTLV-1 tax mRNA expression is reported to correlate with disease severity in HAM/TSP patients, we hypothesize that HTLV-1 tax may convert HTLV-1 infected T-cells into abnormal IFN-γ producing Th1-like T-cells in HAM/TSP. In this study, we present the molecular mechanisms underlying the plasticity of HTLV-1 infected CD4+CD25+CCR4+ T-cells through HTLV-1 tax.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Yoshihisa Yamano.

Rights and permissions

Open Access This article is published under license to BioMed Central Ltd. This is an Open Access article is distributed under the terms of the Creative Commons Attribution License ( ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Reprints and permissions

About this article

Cite this article

Araya, N., Sato, T., Utsunomiya, A. et al. The plasticity of HTLV-1 infected CD4+CD25+CCR4+ T-cells through HTLV-1 tax in HAM/TSP. Retrovirology 8 (Suppl 1), A104 (2011).

Download citation

  • Published:

  • DOI: