MKI67 and type 1 diabetes mellitus: Interestingly, the frequency of proliferating Ki67+ cells within the memory Treg compartment, and more specifically within the FOXP3hiCD45RO+ memory Treg subset, was lower in children with T1D (Figure 5D and Supplementary Figure 3), providing further evidence of alterations in the memory Treg compartment in T1D.