Small Molecule Mesengenic Induction of Human Induced Pluripotent Stem Cells to Generate Mesenchymal Stem/Stromal Cells

Abstract

The translational potential of mesenchymal stem/stromal cells (MSCs) is limited by their rarity in somatic organs, heterogeneity, and need for harvest by invasive procedures. Induced pluripotent stem cells (iPSCs) could be an advantageous source of MSCs, but attempts to derive MSCs from pluripotent cells have required cumbersome or untranslatable techniques, such as coculture, physical manipulation, sorting, or viral transduction. We devised a single-step method to direct mesengenic differentiation of human embryonic stem cells (ESCs) and iPSCs using a small molecule inhibitor. First, epithelial-like monolayer cells were generated by culturing ESCs/iPSCs in serum-free medium containing the transforming growth factor-␤ pathway inhibitor SB431542. After 10 days, iPSCs showed upregulation of mesodermal genes (MSX2, NCAM, HOXA2) and downregulation of pluripotency genes (OCT4, LEFTY1/2). Differentiation was then completed by transferring cells into conventional MSC medium. The resultant development of MSC-like morphology was associated with increased expression of genes, reflecting epithelial-to-mesenchymal transition. Both ESC-and iPSC-derived MSCs exhibited a typical MSC immunophenotype, expressed high levels of vimentin and N-cadherin, and lacked expression of pluripotency markers at the protein level. Robust osteogenic and chondrogenic differentiation was induced in vitro in ES-MSCs and iPS-MSCs, whereas adipogenic differentiation was limited, as reported for primitive fetal MSCs and ES-MSCs derived by other methods. We conclude that treatment with SB431542 in two-dimensional cultures followed by culture-induced epithelial-to-mesenchymal transition leads to rapid and uniform MSC conversion of human pluripotent cells without the need for embryoid body formation or feeder cell coculture, providing a robust, clinically applicable, and efficient system for generating MSCs from human iPSCs. STEM CELLS TRANSLATIONAL MEDICINE 2012;1:83-95

Activin/Nodal Signaling Switches the Terminal Fate of Human Embryonic Stem Cell-derived Trophoblasts

“…In mouse trophoblast stem cells, activin promotes the acquisition of a labyrinth cell fate (60). Interestingly, the occurrence of EMT upon passage of SB431542-treated hESCs has been reported but in dissimilar culture conditions (61,62).…”

iPSC-MSCs Combined with Low-Dose Rapamycin Induced Islet Allograft Tolerance Through Suppressing Th1 and Enhancing Regulatory T-Cell Differentiation

“…Recent reports have described MSC-like cells derived from iPSCs [33][34][35] with a greater proliferative capacity, lower immunogenicity, and greater immunoregulatory function compared with primary MSC cultures [33,43,45]. In addition, these iPSC-MSCs did not exhibit the tumorigenic properties associated with iPSCs [50,51], implying that iPSC-MSCs may be a safer MSC source.…”

“…Therefore, it is important to identify alternative sources of MSCs before they can be used as a mainstream treatment for organ transplantation. A breakthrough in the generation of humaninduced pluripotent stem cells (iPSCs) from adult somatic cells offered the possibility of generating a high yield of MSCs [33][34][35].…”

Stem cell therapy for inflammatory bowel disease

“…Induced pluripotent stem cells (iPSCs) are pluripotent cells derived from terminally differentiated cells by dedifferentiation. The generation of iPSCs creates the possibility of generating tissue-specific cells, including HSCs [63][64][65][66][67][68] or MSCs [69][70][71][72][73][74][75][76], but further study is required before clinical application of iPSCs can commence. Taken together, immune reconstruction and modification of genetic predisposition of hematopoietic stem cells are important for radical cure of IBD.…”