Double-edged HIV-specific CD4+ T Cells?
Recent findings suggest that HIV persistence in 'Elite Controllers' is driven by the strong specific CD4+ T cell response that allows these patients to remain stable.
A study published ahead of print on January 8, 2011 in Clinical Infectious Diseases (Peter Hunt et al. CID 2011) suggests that in "Elite Controllers", strong HIV-specific CD4+ T cell responsess, while contributing to a potent adaptive immune response, may also contribute to viral persistence. Although this study wasa correlation study, and HIV RNA and DNA cell quantitation not done on specific T cells fractions, the model is interesting.
Thirty eight HIV controllers (HIV RNA < 50 copies/ml for more than 5 years without ART) were analysed. Most of them has normal CD4+ T cell counts (median: 746 cells/mm3). A strong relationship between activated and HIV-specific CD4+ T frequencies and cell-associated HIV burden was found, although no evidence of a relationship between activated and HIV-specific CD8+ T cell frequencies and cell-associated HIV burden was found.
These data support a model in which HIV-specific CD4+ T cells may replenish the latent reservoir and prevent the natural eradication of HIV infection in HIV controllers, and suggest that the latent reservoir in HIV controllers is more highly concentrated in the HIV-specific CD4+ T cell population than in most other HIV-infected individuals..