Author Affiliations
Abstract
1 Molecular Imaging Laboratory, Department of Radiology University of Pennsylvania, School of Medicine Philadelphia, PA 19104, USA
2 Britton Chance Laboratory of Redox Imaging Johnson Research Foundation Department of Biochemistry and Biophysics University of Pennsylvania, School of Medicine Philadelphia, PA 19104, USA
3 Institute for Regenerative Medicine and Department of Cell and Developmental Biology University of Pennsylvania, School of Medicine Philadelphia, PA 19104, USA
4 Institute of Translational Medicine and Therapeutics University of Pennsylvania, Philadelphia, PA 19104, USA
Redox state mediates embryonic stem cell (ESC) differentiation and thus offers an important complementary approach to understanding the pluripotency of stem cells. NADH redox ratio (NADH/(Fp+ NADH)), where NADH is the reduced form of nicotinamide adenine dinucleotide and Fp is the oxidized flavoproteins, has been established as a sensitive indicator of mitochondrial redox state. In this paper, we report our redox imaging data on the mitochondrial redox state of mouse ESC (mESC) colonies and the implications thereof. The low-temperature NADH/Fp redox scanner was employed to image mESC colonies grown on a feeder layer of gamma-irradiated mouse embryonic fibroblasts (MEFs) on glass cover slips. The result showed significant heterogeneity in the mitochondrial redox state within individual mESC colonies (size: ~200-440 μm), exhibiting a core with a more reduced state than the periphery. This more reduced state positively correlates with the expression pattern of Oct4, a well-established marker of pluripotency. Our observation is the first to show the heterogeneity in the mitochondrial redox state within a mESC colony, suggesting that mitochondrial redox state should be further investigated as a potential new biomarker for the stemness of embryonic stem cells.
Redox imaging pluripotency NADH flavoproteins redox ratio Journal of Innovative Optical Health Sciences
2011, 4(3): 279
