GB virus type C infection modulates T-cell activation independently of HIV-1 viral load

• Autor(a) principal: Maidana-Giret, Maria Teresa [UNIFESP]
• Data de Publicação: 2009
• Outros Autores: Silva, Tania M. [UNIFESP], Sauer, Mariana M. [UNIFESP], Tomiyama, Helena [UNIFESP], Levi, Jose Eduardo, Bassichetto, Katia Cristina, Nishiya, Anna, Diaz, Ricardo S. [UNIFESP], Sabino, Ester Cerdeira [UNIFESP], Palacios, Ricardo [UNIFESP], Kallas, Esper Georges [UNIFESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: http://dx.doi.org/10.1097/QAD.0b013e32832d7a11; http://repositorio.unifesp.br/handle/11600/31949
• topic: activation; CD38; coinfection; GB virus type C; HIV-1; T lymphocyte

Background: Many clinical studies have suggested a beneficial effect of GB virus type C (GBV-C) on the course of HIV-1 infection, but the mechanisms involved in such amelioration are not clear. As recent evidence has implicated cellular activation in HIV-1 pathogenesis, we investigated the effect of GBV-C viremia on T-cell activation in early HIV-1 infection.Methods: Forty-eight recently infected HIV-1 patients (23 GBV-C viremic) were evaluated for T-cell counts, expanded immunophenotyping GBV-C RNA detection, and HIV-1 viral load. Nonparametric univariate and multivariate analyses were carried out to identify variables associated with cellular activation, including GBV-C status, HIV-1 viral load, T lymphocyte counts, and CD38 and chemokine (C-C motif) receptor 5 (CCR5) surface expression.Finding: We not only confirmed the positive correlation between HIV-1 viral load and the percentage of T cells positive for CD38(+)CD8(+) but also observed that GBV-C viremic patients had a lower percentage of T cells positive for CD38(+)CD4(+), CD38(+)CD8(+), CCR5(+)CD4(+), and CCR5(+)CD8(+) compared with HIV-1-infected patients who were not GBV-C viremic. in regression models, GBV-C RNA(+) status was associated with a reduction in the CD38 on CD4(+) or CD8(+) T cells and CCR5(+) on CD8(+) T cells, independent of the HIV-1 viral load or CD4(+) and CD8(+) T-cell counts. These results were also supported by the lower expression of CD69 and CD25 in GBV-C viremic patients.Interpretation: the association between GBV-C replication and lower T-cell activation may be a key mechanism involved in the protection conferred by this virus against HIV-1 disease progression to immunodeficiency in HIV-1-infected patients. (C) 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins