Isolation of human iPSC-derived dopaminergic progenitors by cell sorting

Human induced pluripotent stem cells (iPSCs) can provide a promising source of midbrain dopaminergic (DA) neurons for cell replacement therapy for Parkinson’s disease. However, iPSC-derived donor cells may inevitably contain tumorigenic or inappropriate cells. Purification of neural progenitor cells or DA neurons as suitable donor cells has been attempted, but the isolation of DA progenitor cells derived from human pluripotent stem cells has so far been unsuccessful. Here we show human iPSC-derived DA progenitor cells can be efficiently isolated by cell sorting using a floor plate marker, Corin. we were able to develop a method for 1) scalable DA neuron induction on human laminin fragment and 2) sorting DA progenitor cells using an anti-Corin antibody. Furthermore, we determined the optimal timing for the cell sorting and transplantation. The grafted cells survived well and functioned as midbrain DA neurons in the 6-OHDA-lesioned rats, and showed minimal risk of tumor formation. The sorting of Corin-positive cells is favorable in terms of both safety and efficiency, and our protocol will contribute to the clinical application of human iPSCs for Parkinson’s disease. Differentiated human iPSC-derived neural progenitors just after sorting (day12 unsorted, day12 Corin+) and dopaminergic progenitors after an aggregation culture (day28 and day42, unsorted and day12-sorted, respectively), and human fetal ventral mesencephalon and dorsal mesencephalon (gestational age of 7.5 weeks) were subjected to RNA extraction and hybrdization on Affymetrix microarrays. Each sample except for human mesencephalon, undifferentiated iPSC, and day12-unsorted, day42-sample has 3 or 4 repeats.