Human iPSC-derived dopaminergic neurons function in primate Parkinson’s disease models

Induced pluripotent stem cells (iPSCs) are a promising source for cell-based therapy to treat Parkinson's disease (PD), in which midbrain dopaminegic (DA) neurons progressively degenerate. However, long-term analysis of human iPSC-derived DA neurons in primate PD models has never been performed. Here we show that DA progenitor cells derived from iPSCs of both healthy individuals and PD patients survived well in the brains of PD model primates and improved animal behavior. Magnetic resonance and positron emission tomography were useful to monitor the survival and function of the DA neurons. Score-based and video-recording analyses revealed an increase in spontaneous movement of the monkeys after transplantation. Histological studies showed that the mature DA neurons extended dense neurites into the host striatum. In addition, we never observed tumor formation for two years. Thus, this preclinical study using primate models indicates that human iPSC-derived DA progenitors are clinically applicable to treat PD patients.