Objective:To investigate the role of the CD38/p53/ME1 axis in regulating T cell mitochondrial function and senescence during HIV infection.Methods:The expression of CD38 on T cells was examined in HIV-infected individuals receiving antiretroviral therapy(ART), untreated HIV-infected individuals, and HIV-negative healthy controls. Flow cytometry was used to compare senescence markers and mitochondrial function between CD38 + and CD38 - T cells. Malic enzyme 1(ME1) mRNA levels were measured by qRT-PCR in T cells treated with the CD38 inhibitor 78c. Mitochondrial function and senescence were assessed in T cells treated with an ME1 inhibitor. The regulatory mechanism of CD38-mediated ME1 downregulation was further explored. Results:Compared to healthy controls, T cells from HIV-infected individuals exhibited significantly elevated CD38 expression, which persisted despite ART. CD38 + T cells showed increased senescence (CD28 -CD57 + subset) and mitochondrial dysfunction[depolarization and reactive oxygen species(ROS) accumulation]. CD38 inhibition upregulated ME1 mRNA level ( P<0.05). ME1 suppression led to mitochondrial impairment (reduced membrane potential and elevated ROS) and senescence in T cells. Mechanistically, CD38 depletion increased NAD + levels and SIRT1 activity, while SIRT1/p53 inhibition rescued ME1 expression, suggesting CD38 regulates ME1 via the NAD + /SIRT1/p53 axis. Conclusions:The CD38/p53/ME1 axis drives T cell senescence in HIV infection by disrupting mitochondrial function. Targeting this pathway may ameliorate CD38-associated T cell dysfunction and immune aging.

Objective:To investigate the role of the CD38/p53/ME1 axis in regulating T cell mitochondrial function and senescence during HIV infection.Methods:The expression of CD38 on T cells was examined in HIV-infected individuals receiving antiretroviral therapy(ART), untreated HIV-infected individuals, and HIV-negative healthy controls. Flow cytometry was used to compare senescence markers and mitochondrial function between CD38 + and CD38 - T cells. Malic enzyme 1(ME1) mRNA levels were measured by qRT-PCR in T cells treated with the CD38 inhibitor 78c. Mitochondrial function and senescence were assessed in T cells treated with an ME1 inhibitor. The regulatory mechanism of CD38-mediated ME1 downregulation was further explored. Results:Compared to healthy controls, T cells from HIV-infected individuals exhibited significantly elevated CD38 expression, which persisted despite ART. CD38 + T cells showed increased senescence (CD28 -CD57 + subset) and mitochondrial dysfunction[depolarization and reactive oxygen species(ROS) accumulation]. CD38 inhibition upregulated ME1 mRNA level ( P<0.05). ME1 suppression led to mitochondrial impairment (reduced membrane potential and elevated ROS) and senescence in T cells. Mechanistically, CD38 depletion increased NAD + levels and SIRT1 activity, while SIRT1/p53 inhibition rescued ME1 expression, suggesting CD38 regulates ME1 via the NAD + /SIRT1/p53 axis. Conclusions:The CD38/p53/ME1 axis drives T cell senescence in HIV infection by disrupting mitochondrial function. Targeting this pathway may ameliorate CD38-associated T cell dysfunction and immune aging.