Immune Activation While on Potent Antiretroviral Therapy Can Predict Subsequent CD4+ T-Cell Increases Through 15 Years of Treatment.

BACKGROUND: While persistent T-cell activation has been cross-sectionally associated with poor CD4+ T-cell restoration in HIV-infected individuals maintaining antiretroviral treatment (ART)-mediated viral suppression, it remains unclear whether CD8+ T-cell activation is of predictive effect on CD4+ T-cell recovery.
OBJECTIVE: We assessed whether the extent of persistent CD8+ T-cell activation (% CD38+/HLA-DR+) in the first few years of ART-mediated viral suppression predicted subsequent CD4+ T-cell recovery in 95 subjects with up to 15 years of observation on suppressive ART.
RESULTS: Lower CD8+ T-cell activation and higher naïve CD4+ T-cell frequencies (CD45RA+/CD62L+) measured at year 3 to 5 after starting ART independently predicted greater subsequent CD4+ T-cell increases. The mean CD4 count increase from year 0 to year 5 and the increase to the average of year 10 to 15 in the low CD8 activation group (≤18.5%; mean = 13%) were 342 and 458 cells/mm,3 and the increases were 248 and 349 cells/mm3 for the high CD8 activation group (≯18.5%; mean = 29%) (P = .002 and P = .016, respectively, comparing groups). At years 10 to 15, the mean CD4 counts in the groups were 579 and 484 cells/mm3, respectively (P = .026).
CONCLUSION: These findings support the need to identify approaches to reduce immune activation in treated HIV disease.