Persistent CD8+ T-cell activation (HLA-DR/CD38) as an immunological marker in antiretroviral-treated human...

ObjectiveTo analyze the relationship among CD8+ T-cell activation markers (CD38/human leukocyte antigen-D-related (HLA-DR)), viral load, and CD4+/CD8+ counts in patients with human immunodeficiency virus-1 receiving antiretroviral therapy in Southern Turkey and evaluate their potential as indicators of persistent immune activation.MethodsNinety-nine patients receiving antiretroviral therapy were included in this cross-sectional study. Human immunodeficiency virus RNA was quantified using real-time polymerase chain reaction, whereas CD4+, CD8+, and activation markers (CD38, HLA-DR) were analyzed using flow cytometry.ResultsPatients with detectable viral load (viral load ≥20 copies/mL) had significantly higher percentages of CD8+ CD38+, CD8+ HLA-DR+, and dual-positive CD8+ CD38+ HLA-DR+ T-cells than those with suppressed viral load (<20 copies/mL) (all p < 0.05). The correlation with viral load was moderate for CD8+ T-cells alone (rho = 0.40, p < 0.001) and remained significant for CD38+ CD8+ T-cells (rho = 0.39, p < 0.001); it was stronger for HLA-DR+ CD8+ T-cells (rho = 0.55, p < 0.001) and HLA-DR+ CD38+ CD8+ T-cells (rho = 0.46, p < 0.001). Patients with coinfections showed significantly higher levels of these activation markers.ConclusionsFindings suggest that CD8+ activation markers serve as potential immunological indicators of persistent immune activation and dysfunction. These markers may help identify patients at risk for inflammaging and incomplete recovery despite suppressed viral loads, offering valuable insights for personalized management in the antiretroviral therapy era.