Direct Comparison of Four Hematopoietic Differentiation Methods from Human Induced Pluripotent Stem Cells.

Induced pluripotent stem cells (iPSCs) are an invaluable resource for the study of human disease. However, there are no standardized methods for differentiation into hematopoietic cells, and there is a lack of robust, direct comparisons of different methodologies. In the current study we improved a feeder-free, serum-free method for generation of hematopoietic cells from iPSCs, and directly compared this with three other commonly used strategies with respect to efficiency, repeatability, hands-on time, and cost. We also investigated their capability and sensitivity to model genetic hematopoietic disorders in cells derived from Down syndrome and ß-thalassemia patients. Of these methods, a multistep monolayer-based method incorporating aryl hydrocarbon receptor hyperactivation ("2D-multistep") was the most efficient, generating significantly higher numbers of CD34+ progenitor cells and functional hematopoietic progenitors, while being the most time- and cost-effective and most accurately recapitulating phenotypes of Down syndrome and ß-thalassemia.

Advances in reprogramming to pluripotency.

Pluripotent stem cells (PSCs) derived from somatic cells represent a powerful experimental tool for investigating the molecular mechanisms underlying the disease phenotype; with prospects to advance medical therapies. They also have significant potential as a renewable source of autologous cells for cellular therapy. Various approaches for PSC derivation from somatic cells have been reported in the literature. The method used for reprogramming is particularly relevant as it may affect the characteristics and quality of PSCs. This review will present an overview of the basic strategies and methods for reprogramming to pluripotency. These strategies will be briefly discussed in the context of how the mechanism of reprogramming could influence PSC characteristics with respect to safety and quality. Aspects of the reprogramming approach that can influence PSC properties, such as culture conditions and donor cell source, are also discussed.