Kidney regeneration from human induced pluripotent stem cells

Purpose of review Human induced pluripotent stem cells (iPSCs) and embryonic stem cells (ESCs) are potential unlimited cell sources for renal cells in regenerative medicine. This review highlights recent advance in the directed differentiation of human iPSCs into kidney lineages and discusses the remaining challenges to generate functional or mature renal cells from human iPSCs. Recent findings Recently, directed differentiation methods from human iPSCs/ESCs into embryonic renal progenitor cells, such as those included in metanephric mesenchyme and ureteric bud, that mimic embryonic development have been reported. These studies show the developmental potential of progenitor cells by forming renal tubule-like or glomerulus-like structures in vitro. However, it has not been verified whether the physiological functions of the induced progenitors are equivalent to their in-vivo counterparts. The establishment of definitive marker genes for kidney lineages and functional assay systems is essential for the verification. Such achievement is needed before kidney regeneration can provide cell replacement therapy, reliable disease models and elucidation of the mechanisms of kidney development. Summary In conclusion, this review outlines milestones in directed differentiation methods for functional renal cell types from human iPSCs toward clinical application and practical use.