Long-term self-renewable feeder-free human induced pluripotent stem cell-derived neural progenitors.

Human induced pluripotent stem cells (hiPSCs) have led to an important revolution in stem cell research and regenerative medicine. To create patient-specific neural progenitors (NPs), we have established a homogenous, expandable, and self-renewable population of multipotent NPs from hiPSCs, using an adherent system and defined medium supplemented with a combination of factors. The established hiPSC-NPs highly expressed Nestin and Sox1. These NPs were continuously propagated for ~1 year without losing their potential to generate astrocytes, oligodendrocytes, and functional neurons and maintained a stable chromosome number. Voltage clamp analysis revealed outward potassium currents in hiPSC-NPs. The self-renewal characteristic of the NPs was demonstrated by a symmetrical mode of Nestin-positive cell division. Additionally, these hiPSC-NPs can be easily frozen and thawed in the presence of Rho-associated kinase (ROCK) inhibitor without losing their proliferation, karyotype stability, and developmental potential. The characteristics of our generated hiPSC-NPs provide the opportunity to use patient-specific or ready-to-use hiPSC-NPs in future biomedical applications.