Submitted on June 7, 2007
Accepted on August 21, 2007
TISSUE-SPECIFIC STEM CELLS
|
Enhanced oxygenation promotes beta cell differentiation in vitro
Christopher A. Fraker 1,
Silvia Álvarez 2,
Panagiotis Papadopoulos 2,
Jaime Giraldo 2,
Weiyong Gu 3,
Camillo Ricordi 2,
Luca Inverardi 2,
Juan Domínguez-Bendala 2*
1 Diabetes Research Institute, University of Miami Leonard M. Miller School of Medicine, 1450 NW 10th Avenue, Miami, FL 33136; Department of Biomedical Engineering; University of Miami, P.O. Box 248294, Coral Gables, FL 33124
2 Diabetes Research Institute, University of Miami Leonard M. Miller School of Medicine, 1450 NW 10th Avenue, Miami, FL 33136
3 Department of Biomedical Engineering; University of Miami, P.O. Box 248294, Coral Gables, FL 33124
* To whom correspondence should be addressed. E-mail: jdominguez2{at}med.miami.edu.
 |
Abstract |
|---|
Despite progress in our knowledge about pancreatic islet specification, most attempts at differentiating stem/progenitor cells into functional, transplantable
cells have met only with moderate success thus far. A major challenge is the intrinsic simplicity of in vitro culture systems, which cannot approximate the physiological complexity of in vivo microenvironments. Oxygenation is a critical limitation of standard culture methods -and one of special relevance for the development of
cells, known for their high O2 requirements. Based on our understanding of islet physiology, we have tested the hypothesis that enhanced O2 delivery (as provided by novel perfluorocarbon-based culture devices) may result in higher levels of
cell differentiation from progenitor cells in vitro. Using a mouse model of pancreatic development, we demonstrate that a physiological-like mode of O2 delivery results in a very significant up-regulation of endocrine differentiation markers (up to 30-fold for insulin 1 and 2), comparable to relevant in vivo controls. This effect was not observed by merely increasing environmental O2 concentrations in conventional settings. Our findings indicate that O2 plays an important role in the differentiation of
cells from their progenitors, and may open the door to more efficient islet differentiation protocols from embryonic and/or adult stem cells.
Key Words.
stem cells, islets, perfluorocarbon, oxygenation, beta cells