Project description:Recent studies have shown that defined hepatic factors could lead to the direct conversion of fibroblasts into induced hepatocytes (iHeps). However, reported conversion efficiencies are vey low and the underlying mechanism of the hepatic lineage conversion is largely unknown. Here, we report that direct conversion into iHeps is a stepwise transition involving erasure of somatic memory, mesenchymal-to-epithelial transition, and induction of hepatic cell fate in a sequential manner. Throughout screening for additional factors that could potentially enhance the kinetics of the MET and hepatic programs, we have found that c-Myc and Klf4 (CK) dramatically accelerate the conversion kinetics, resulting in remarkably improved generation of iHeps (>87 fold). Furthermore, we identified small molecules that could replace the roles of CK and thus led to the highly efficient generation of iHeps without CK. Finally, we show that a single factor (Hnf1α) supported by small molecules is sufficient to robustly induce transprogramming of fibroblasts into functional hepatocyte-like cells with high yield. This novel approach might help to fully elucidate the direct conversion process and also facilitate the translation of iHep into clinic.
Project description:Forced expression of pro-neural transcription factors was shown to mediate direct neuronal conversion of human fibroblasts. Since neurons are postmitotic, the conversion efficiency represents an important parameter. Here we present a minimalist approach combining two factor neuronal programming with small molecule-based inhibition of GSK3ß and SMAD signaling, which gives rise to functional neuron-like cells (iNs) of various neurotransmitter phenotypes with an overall yield of up to >200% and a final neuronal purity of up to >80%. Timcourse of reprogramming of fibroblasts towards an neuronal phenotype in two independent fibroblast lines
Project description:Here we performed the first combinatorial small molecule screen for the rapid conversion of hPSCs into postmitotic neurons. We identified a combination of five small molecule pathway inhibitors sufficient to yield neurons at > 75% efficiency within 10 days of differentiation in the absence of any recombinant growth factors. The resulting human neurons express canonical markers of nociceptive sensory fate. Two treatments (LSB and 3i) at days 2,3,5,7,9, and 15, in triplicate
Project description:Rapid and efficient conversion of common marmoset fibroblasts into mature and functional neurons by overexpression of ASCL1 and microRNA-9/9*-124
Project description:Here we performed the first combinatorial small molecule screen for the rapid conversion of hPSCs into postmitotic neurons. We identified a combination of five small molecule pathway inhibitors sufficient to yield neurons at > 75% efficiency within 10 days of differentiation in the absence of any recombinant growth factors. The resulting human neurons express canonical markers of nociceptive sensory fate.
Project description:Forced expression of pro-neural transcription factors was shown to mediate direct neuronal conversion of human fibroblasts. Since neurons are postmitotic, the conversion efficiency represents an important parameter. Here we present a minimalist approach combining two factor neuronal programming with small molecule-based inhibition of GSK3ß and SMAD signaling, which gives rise to functional neuron-like cells (iNs) of various neurotransmitter phenotypes with an overall yield of up to >200% and a final neuronal purity of up to >80%.
