Background: Despite the contraindications, stopping treatment for HIV infection continues to be a common practice. Understanding whether T-cell proliferative capacity and phenotypic markers before treatment interruption (TI) can predict CD4+ T-cell count change and nadir during TI would be clinically useful.
Methods: This retrospective study included 27 HIV-infected patients in the chronic phase of infection while on combination antiretroviral therapy (cART) who underwent a TI. Peripheral blood mononuclear cells from a baseline pre-TI time point were screened for T-cell proliferation to cytomegalovirus (CMV) lysate, an HIV Gag p55 peptide pool as well as positive and negative control stimuli. CD28 and CD57 expression on CD4+ and CD8+ T-cells were measured.
Results: Baseline viral load, CD4+ T-cell count, pre-cART nadir CD4+ T-cell and percentage CD4+CD28+ T-cells were all predictive of the lowest CD4+ T-cell count during TI (Spearman's correlation P<0.05 for all analyses). In addition, CD4+ and CD8+ T-cells proliferation to CMV lysate, baseline CD4+ T-cell count and percentage CD4+CD57+ T-cells correlated negatively with CD4+ T-cell decrease during TI (Spearman's correlation P<0.05 for all analyses).
Conclusions: In treated chronic HIV-infected patients, pre-TI immune parameters are potential predictors for both the nadir CD4+ T-cell count and CD4+ T-cell count decrease during TI.