IKZF2 and type 1 diabetes mellitus: However, when compared to Helios+ Tregs, we observed Helios− Tregs showed much lower expression of FOXP3 (in terms of mean fluorescence intensity, MFI), but much higher proportion of CD25− /low Tregs in both T1D and healthy individuals (Figures 1D, E), suggesting reduced stability in Helios− Tregs similar to previous results (16, 21).