Enhanced oxygenation promotes β-cell differentiation in vitro

Despite progress in our knowledge about pancreatic islet specification, most attempts at differentiating stem/progenitor cells into functional, transplantable β 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 β 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 β-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 upregulation of endocrine differentiation markers (up to 30-fold for insulin one 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 β cells from their progenitors and may open the door to more efficient islet differentiation protocols from embryonic and/or adult stem cells.