PHENOTYPIC AND METABOLIC FEATURES OF CD4 AND CD8 T CELLS OF AN ELITE CONTROLLER

Background: People living with HIV (PLHIV) who are capable of long-term viral suppression in the absence of antiretroviral therapy (ART) are defined as elite controllers (EC). Although there is evidence of phenotypic and functional alterations of T-lymphocytes in EC, neither the mechanisms of viral control, nor the necessity and timing of ART in this particular population have been elucidated. Case presentation: We report the case of untreated HIV+ patient with undetectable viral load (VL), and preserved CD4 T cell absolute count (AC) and CD4/CD8 ratio since diagnosis in 2018. The detailed phenotype of EC CD4 and CD8 T cell pools including differentiation, effector, activation, immunosenescence and exhaustion markers was distinct from sex- and age-matched ART+PLHIV with immune recovery, and close to HIV(-) healthy controls (HC), except for a temporary increase of CD57+ CD8 T cells in 2023. The only changing biomarkers were T cell mitochondrial mass (MM), slightly increased at the level of CD8 T cells in 2023, and drastically increased in both CD4 and CD8 T in 2025, together with the mitochondrial membrane potential (MMP), as compared to ART+PLHIV and HIV (-) HC. Conclusions: CD4 and CD8 T cells of EC experience intensive oxidative stress and functional burden, possibly linked to the continuous effective HIV-specific immune response. CD4 and CD8 T cell MM may serve as a monitoring marker preceding the irreversible changes of immune profile and loss of viral control, and possibly predict the time for start of ART.