The results showed no difference in frequency of CD3+ T cells (Student's t-test, t = 1.718, df = 5, p = 0.146) and CD4+ T cells (Student's t-test, t = 1.764, df = 5, p = 0.138) in the total splenocytes derived from young WT mice and old AD mice (Figure 5A–5D), however, it was noted that there was a higher frequency of Tregs in oSCs (Student's t-test, t = 2.272, df = 5, p = 0.028) (Figure 5E, 5F). Here, CD4 is linked to Alzheimer disease.