MKI67 and juvenile idiopathic arthritis: (B) Percentage CD25+FOXP3+ Treg of CD3+CD4+ cells in SFMC and PBMC of JIA patients and healthy children, and percentage of Ki67+ cells within CD45RA− cells in Treg and non-Treg in SFMC (nonparametric Mann-Whitney, *=p<0.05).