Reduced mitochondrial properties in putative progenitor/stem cells of human keratinocytes.

BACKGROUND The characterization of progenitor/keratinocyte stem cells (KSC) remains an unachieved goal. A previous study showed that rapid adhering cells to collagen IV had the characteristics of putative progenitor/KSCs. OBJECTIVE The purpose of this study was to investigate the genetic expression of rapid adhering cells compared to non adhering cells to determine the characteristic of KSCs. METHODS We isolated rapid adhering cells representative of KSCs from non adhering cells representative of transient amplifying cells. In addition, we differentiated cells from human tonsilar keratinocytes utilizing the adhering capability of the KSCs to collagen IV. Annealing control primer based differentially displayed polymerase chain reaction (PCR) was performed as well as Western blot analysis. RESULTS The levels of mitochondria-related gene expression were low in the rapid adhering cells compared to the non adhering cells. Mitochondrial complex I, COX IV, peroxiredoxins (I, II and IV) and mitochondrial membrane potential were all low in the rapid adhering cells compared to the non adhering cells. CONCLUSION Using an adhesion method on human collagen IV-coated plates, our results suggest that reduced mitochondrial function may be an important characteristic of KSCs.