In our study, which is a pilot research, requiring a further confirmation of the results on a bigger cohort of patients, we fully analysed the Tregs (CD4+/CD25high/CD127low-neg) and their different functional subsets (Resting (CD45RApos/CD25dim), Activated (CD45RAneg/CD25bright), and Secreting (CD45RAneg/CD25dim)15,41,42,47 in terms of frequencies, as well as in respect to their CD39 and HLA-DR surface expression, in the AD and in the MS patients, as compared to healthy donors. Here, CD4 is linked to Alzheimer disease.