Analysis of Insulin-Producing Cells During In Vitro Differentiation From Feeder-Free Embryonic Stem Cells

Analysis of Insulin-Producing Cells During In Vitro Differentiation From Feeder-Free Embryonic Stem Cells Yusuke Moritoh , Eiji Yamato , Yumiko Yasui , Satsuki Miyazaki and Jun-ichi Miyazaki From the Division of Stem Cell Regulation Research, Osaka University Graduate School of Medicine, Suita, Japan Abstract Embryonic stem (ES) cells can differentiate into many cell types and are expected to be useful for tissue engineering. Recent reports have shown that ES cells can differentiate into insulin-producing cells in response to the transient expression of the pdx-1 gene, after the removal of feeder cells. To investigate the lineage of insulin-producing cells and their in vitro differentiation, we introduced the βgeo gene, encoding a β-galactosidase-neomycin phosphotransferase fusion protein under the control of the mouse insulin 2 promoter, into ES cells that had been adapted to feeder-free culture, and analyzed insulin gene expression during their in vitro differentiation. We also examined the expression of transcription factors that are related to the differentiation of the pancreas. X-gal staining analysis revealed β-galactosidase-positive cells on the surface and in the center of the embryoid body that proliferated during differentiation. Glucose-responsive insulin-producing cells, derived from our feeder-free ES cells, expressed insulin 2, pdx-1, Pax4, and Isl1 and also the glucagon, somatostatin, and PP genes. Moreover, the genes encoding p48, amylase, and carboxypeptidase A were also expressed. These results suggest that ES cells can differentiate not only into endocrine cells but also into exocrine cells of the pancreas, without the initiation of pdx-1 expression. Footnotes Address correspondence and reprint requests to Jun-ichi Miyazaki, Division of Stem Cell Regulation Research (G6), Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan. E-mail: jimiyaza{at}nutri.med.osaka-u.ac.jp . Received for publication 7 October 2002 and accepted in revised form 24 January 2003. β-gal, β-galactosidase; EB, embryoid body; ES, embryonic stem; IAPP, islet amyloid polypeptide; LIF, leukemia inhibitory factor; pgk, phosphoglycerate-kinase; PP, pancreatic polypeptide. DIABETES