CD4 and type 1 diabetes mellitus: We show that type 1 diabetics (T1D) have a Treg activation defect through an increase in resting Tregs (rTregs, CD4+CD25+Foxp3+CD45RA) and decrease in aTregs (CD4+CD25+Foxp3+CD45RO) (n= 55 T1D, n=45 controls, P=0.01).