CD4 and Alzheimer disease: In the AD group, the proportions of peripheral CD4+CD127lowCD25+ Tregs were statistically significantly positively related to the amount of the neuronal injury marker total Tau in CSF (r = 0.433, p = 0.021, n = 28), to pTau (r = 0.462, p = 0.024, n = 28), and to Aβ 40 (r = 0.484, p = 0.009, n = 28) (Figure 2).