We have recently reported that CD4 T cells from patients with chronic HCV or HIV infection age prematurely or become senescent due to telomeric and mitochondrial DNA damage (Yao and Moorman, 2013; Shi et al., 2014; Li et al., 2015; Zhou et al., 2016; Nguyen et al., 2018; Zhao et al., 2018; Cao et al., 2019; Ji et al., 2019; Zhao et al., 2019; Dang, 2020; Khanal et al., 2020; Schank et al., 2020; Khanal et al., 2021; Nguyen L. N. et al., 2021; Nguyen L. N. N. T. et al., 2021; Schank et al., 2021; Schank et al., 2021; Wang et al., 2021; Zhao et al., 2021; Cao et al., 2022). Here, CD4 is linked to HIV infectious disease.