More recently, preclinical studies have shown that human CD34+ cells rapidly home into the damaged retinal vasculature in diabetic retinopathy or retinal acute ischemia-reperfusion injury following intravitreal injection and can repair retinal damage (Caballero et al., 2007; Park et al., 2012; Yazdanyar et al., 2020). Here, CD34 is linked to diabetic retinopathy.