The frequency of CD127(low) expressing CD4(+)CD25(high) T regulatory cells is inversely correlated with human T lymphotrophic virus type-1 (HTLV-1) proviral load in HTLV-1-infection and HTLV-1-associated myelopathy/tropical spastic paraparesis

• Autor(a) principal: Michaelsson, Jakob
• Data de Publicação: 2008
• Outros Autores: Barbosa, Hugo Marcelo Ribeiro [UNIFESP], Jordan, Kimberley A., Chapman, Joan M., Brunialti, Milena Karina Coló [UNIFESP], Kleine Neto, Walter, Nukui, Youko, Sabino, Ester C., Chieia, Marco Antonio [UNIFESP], Oliveira, Acary Souza Bulle [UNIFESP], Nixon, Douglas F., Kallas, Esper Georges [UNIFESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: http://dx.doi.org/10.1186/1471-2172-9-41; http://repositorio.unifesp.br/handle/11600/30805

Background: CD4(+)CD25(high) regulatory T (T(Reg)) cells modulate antigen-specific T cell responses, and can suppress anti-viral immunity. in HTLV-1 infection, a selective decrease in the function of T(Reg) cell mediated HTLV-1-tax inhibition of FOXP3 expression has been described. the purpose of this study was to assess the frequency and phenotype of T(Reg) cells in HTLV-1 asymptomatic carriers and in HTLV-1-associated neurological disease (HAM/TSP) patients, and to correlate with measures of T cell activation.Results: We were able to confirm that HTLV-1 drives activation, spontaneous IFN gamma production, and proliferation of CD4+ T cells. We also observed a significantly lower proportion of CTLA-4(+) T(Reg) cells (CD4(+)CD25(high) T cells) in subjects with HAM/TSP patients compared to healthy controls. Ki-67 expression was negatively correlated to the frequency of CTLA-4(+) T(Reg) cells in HAM/TSP only, although Ki-67 expression was inversely correlated with the percentage of CD127(low) T(Reg) cells in healthy control subjects. Finally, the proportion of CD127(low) T(Reg) cells correlated inversely with HTLV-1 proviral load.Conclusion: Taken together, the results suggest that T(Reg) cells may be subverted in HAM/TSP patients, which could explain the marked cellular activation, spontaneous cytokine production, and proliferation of CD4(+) T cells, in particular those expressing the CD25(high)CD127(low) phenotype. T(Reg) cells represent a potential target for therapeutic intervention for patients with HTLV-1-related neurological diseases.