Circulating cell-free DNA as a biomarker for immune function and disease progression in HIV-infected patients: a cross-sectional observational study.

BACKGROUND

Human immunodeficiency virus type 1 (HIV-1) causes immune deficiency, particularly CD4+T-cell depletion. This cross-sectional study explored circulating cell-free DNA (ccfDNA) as a biomarker for immune function and disease progression in HIV-1-infected individuals.

METHODS

We measured ccfDNA levels, CD4+T-cell counts, immune activation/apoptosis markers, and viral load in 79 patients receiving antiretroviral therapy (37 immune responders, 42 non-responders) and 35 controls. Correlation and receiver operating characteristic (ROC) curve analysis were performed to assess relationships between ccfDNA and immunological/virological parameters.

RESULTS

ccfDNA negatively correlated with CD4+T-cell counts (r = - 0.78, P < 0.01) and positively correlated with viral load (r = 0.58, P < 0.01) and T-cell immune activation/apoptosis markers (r = 0.78 ~ 0.89, P < 0.01). Multivariate regression showed CD4+T-cell counts independently associated with lower ccfDNA, while CD4+AnnexinV+, CD8+PD1+, and CD8+AnnexinV+T cells correlated with higher ccfDNA. ROC analysis (area under curve = 0.799) indicated ccfDNA's potential as a complementary biomarker for monitoring HIV-1 patients.

CONCLUSIONS

Preliminary evidence from this study indicates that ccfDNA levels are closely linked to immune dysfunction and may have potential as a complementary biomarker for monitoring immune status in HIV-1-infected patients.