Details

Autor(en) / Beteiligte

• Sáez-Cirión, Asier
• Lacabaratz, Christine
• Lambotte, Olivier
• Versmisse, Pierre
• Urrutia, Alejandra
• Boufassa, Faroudy
• Barré-Sinoussi, Françoise
• Delfraissy, Jean-François
• Sinet, Martine
• Pancino, Gianfranco
• Venet, Alain

Titel

HIV controllers exhibit potent CD8 T cell capacity to suppress HIV infection ex vivo and peculiar cytotoxic T lymphocyte activation phenotype

Ist Teil von

• Proceedings of the National Academy of Sciences - PNAS, 2007-04, Vol.104 (16), p.6776-6781

Ort / Verlag

United States: National Academy of Sciences

Erscheinungsjahr

2007

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• Some rare HIV-1-infected individuals, referred to as HIV controllers (HIC), have persistently undetectable plasma viral load in the absence of therapy. This control of HIV-1 replication has been associated with a strong, multifunctional specific CD8⁺ T cell response. However, no direct link between this immune response and the control of viremia has so far been provided. We investigated parameters of specific CD8⁺ T cell response and in vitro susceptibility to HIV-1 infection in 11 HIC. We found high frequencies of HIV-specific CD8⁺ T cells. Interestingly, these cells expressed the activation marker HLA-DR but not CD38. This unique phenotype differentiates HIV-specific CD8⁺ T cells from HIC and noncontroller subjects and likely reflects a high potential to expand upon exposure to antigen and a capacity to exert effector functions. Accordingly, although CD4⁺ T cells from HIC were fully susceptible to HIV-1 superinfection, their CD8⁺ T cells effectively suppressed HIV-1 infection. Remarkably, this potent anti-HIV activity was observed without prior stimulation of CD8⁺ T cells. This activity was not mediated by secreted inhibitory factors but was due to the elimination of infected CD4⁺ T cells and was observed only with autologous CD4⁺ T cells, indicating an HLA-restricted cytotoxic mechanism. This constitutive antiviral capacity of CD8⁺ T cells could account for the control of viral replication in HIC.