Generation of Neural Stem Cells (NSCs) from Human Fibroblasts using QQ-Modified Sox2 and NeuroD1 Proteins

Abstract

The generation of induced neural stem cells (iNSCs) and induced neuronal cells (iNCs) from somatic cells provides new avenues for basic research and potential transplantation therapies for neurological diseases. However, clinical applications must consider the tumor formation capabilities of implanted cells, the inability of iNCs to self-renew in culture, and reprogramming methods that use retroviral transduction which permanently alter genetic network of the cells. Here we report the generation of protein-induced neural stem cells (piNSCs) from human dermal fibroblasts using QQ-SON pluripotent reprogramming as a tool to quickly reset the time clock of the human somatic fibroblasts to a transient pluripotent state, followed by QQ-Sox2 and QQ-NeuroD1-guided neural-lineage specific differentiation using our patented QQ-protein delivery technology. The generated piNSCs rely on endogenous gene expression profiles. Furthermore, the generated piNSCs indicate multipotency with the capability of differentiating into neurons, astrocytes, and oligodendrocytes, as confirmed by the cell morphology and their specific biomarker protein expressions. Thus, self-renewable and multipotent piNSCs without tumorigenic potential can be generated from fibroblasts by our method.