Transfer of EPCs during treatment with Ig-GAD2 sustains β-cell regeneration and restores normoglycemia. A: Representative FACS plots depicting FLK-1 expression on Lin−c-Kit+7-AAD− BM cells from age-matched healthy and diabetic mice. B: FLK-1 expression on Lin−c-Kit+7-AAD− BM cells of individually tested mice described in A. C and D: FACS-sorted Lin−c-Kit+FLK-1+ (FLK-1+) or Lin−c-Kit+FLK-1− (FLK-1−) BM cells from healthy (hFLK-1+) or diabetic (sFLK-1+) NOD.GFP donors were used with or without Ig-GAD2 for treatment of diabetic NOD mice. Some of the mice were monitored for
diabetes for 100 days (C), and others (D) were killed on day 60 posttreatment and used for visualizing insulin (blue), PECAM1 (red), and GFP by confocal microscopy
(at least 20 sections per group). The arrows indicate colocalization of PECAM1 and GFP. Scale bars, 10 μm. **P < 0.01.