ABSTRACT: 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:Melanocytes are pigment-producing cells of neural crest origin responsible for protecting the skin against UV-irradiation. Melanocyte dysfunction leads to pigmentation defects including albinism, vitiligo, and piebaldism and is a key feature of systemic pathologies such as Hermansky-Pudlak (HP) and Chediak-Higashi (CH) Syndromes. Pluripotent stem cell technology offers a novel approach for studying human melanocyte development and disease. Here we report that timed exposure to activators of WNT, BMP and EDN3 signaling triggers the sequential induction of neural crest and melanocyte precursor fates under dual-SMAD inhibition conditions. Using a SOX10::GFP hESC reporter line, we demonstrate that the temporal onset of WNT activation is particularly critical for human neural crest induction. Surprisingly, suppression of BMP signaling does reduce neural crest yield. Subsequent differentiation of hESC-derived melanocyte precursors under defined conditions yields pure populations of pigmented cells matching the molecular and functional properties of adult melanocytes. Melanocytes from patient-specific iPSCs faithfully reproduce the ultrastructural features of the HP- and CH-specific pigmentation defects with minimal variability across lines. Our data define a highly specific requirement for WNT signaling during neural crest induction and enable the generation of pure populations of hiPSC-derived melanocytes for faithful modeling of human pigmentation disorders. Total RNA obtained from a timecourse of Dual SMAD Inhibition (DSi), Neural Crest (NC), and Melanocyte (BE) differentiation of human embryonic stem cells in triplicate.
Project description:Melanocytes are pigment-producing cells of neural crest origin responsible for protecting the skin against UV-irradiation. Melanocyte dysfunction leads to pigmentation defects including albinism, vitiligo, and piebaldism and is a key feature of systemic pathologies such as Hermansky-Pudlak (HP) and Chediak-Higashi (CH) Syndromes. Pluripotent stem cell technology offers a novel approach for studying human melanocyte development and disease. Here we report that timed exposure to activators of WNT, BMP and EDN3 signaling triggers the sequential induction of neural crest and melanocyte precursor fates under dual-SMAD inhibition conditions. Using a SOX10::GFP hESC reporter line, we demonstrate that the temporal onset of WNT activation is particularly critical for human neural crest induction. Surprisingly, suppression of BMP signaling does reduce neural crest yield. Subsequent differentiation of hESC-derived melanocyte precursors under defined conditions yields pure populations of pigmented cells matching the molecular and functional properties of adult melanocytes. Melanocytes from patient-specific iPSCs faithfully reproduce the ultrastructural features of the HP- and CH-specific pigmentation defects with minimal variability across lines. Our data define a highly specific requirement for WNT signaling during neural crest induction and enable the generation of pure populations of hiPSC-derived melanocytes for faithful modeling of human pigmentation disorders. Total RNA obtained from embryonic stem cells (ESCs), ESC-derived melanocyte progenitors, ESC-derived mature melanocytes, primary melanocytes, and disease-specific induced pluripotent stem cell-derived melanocytes.
Project description:Neurons derived from human pluripotent stem cells (hPSCs) are a remarkable tool for modeling human neural development and diseases. However, it remains largely unknown whether the hPSC-derived neurons can be functionally coupled with their target tissues in vitro, which is essential for understanding inter-cellular physiology and further translational studies. Here, we demonstrate that hPSC-derived sympathetic neurons can be obtained from hPSCs and that the resulting neurons form physical and functional connections with cardiac muscle cells. By use of multiple hPSC reporter lines, we recapitulated human autonomic neuron development in vitro, and successfully isolated PHOX2B::eGFP+ neurons exhibiting sympathetic marker expression, electrophysiological properties, and norepinephrine secretion. With pharmacological and optogenetic manipulations, the PHOX2B::eGFP+ neurons controlled the beating rates of cardiomyocytes, and their physical interaction led to neuronal maturation. Our study lays a foundation for the specification of human sympathetic neurons and for the hPSC-based neuronal control of end organs in a dish. Using the four genetic reporter systems (OCT4::eGFP, SOX10::eGFP, ASCL1::eGFP, and PHOX2B::eGFP reporter hESC lines), we were able to purify discrete cell populations at four differentiation stages, recapitulating the sympathoadrenal differentiation process in vitro with purified and defined populations in four specific differentiation stages. We performed transcriptome analysis of OCT4::eGFP+ cells (3 biological replicates, representing undifferentiated hESCs), SOX10::eGFP+ cells (3 biological replicates, multi-potent neural crest), ASCL1::eGFP+ cells (3 biological replicates, putative sympathoadrenal progenitors), and PHOX2B::eGFP+ cells (2 biological replicates, putative sympathetic neuronal precursors).
Project description:Unraveling complex signaling programs animating developmental lineage-decisions is pivotal to differentiate human pluripotent stem cells (hPSC) into pure populations of desired lineages for regenerative medicine. Developmental signals are strikingly temporally dynamic: BMP and Wnt initially specify primitive streak (progenitor to endoderm) yet 24 hours later suppress endoderm and induce mesoderm. At lineage bifurcations we show mutually-exclusive embryonic lineages are segregated through cross-repressive signals: TGFM-NM-2 and BMP/MAPK duel to respectively specify pancreas versus liver from endoderm. Unilateral endodermal differentiation requires blockade of alternative fates at every stage, revealing a universal developmental strategy for efficient differentiation and anterior-posterior patterning of diverse hPSC lines into highly-pure endodermal populations. This culminated in hPSC-derived hepatic progenitors that, for the first time, engraft long-term in genetically-unconditioned mouse livers and secrete human albumin. Finally, thirty transcriptional and chromatin state maps capturing endoderm commitment revealed endodermal enhancers reside in an unanticipated diversity of "pre-enhancer" chromatin states before activation. Endoderm RNA-seq and ChIP-seq data sets
Project description:Human pluripotent stem cells (hPSCs) are a promising source of cells for applications in regenerative medicine. Directed differentiation of hPSCs into specialized cells such as spinal motoneurons or midbrain dopamine (DA) neurons has been achieved. However the effective use of hPSCs for cell therapy has lagged far behind. While mouse PSC-derived DA neurons have shown efficacy in models of Parkinson’s disease, DA neurons derived from human PSCs generally display poor in vivo performance. There are also considerable safety concerns for hPSCs related to their potential for teratoma formation or neural overgrowth. Here we present a novel floor plate-based strategy for the derivation of human DA neurons that efficiently engraft, suggesting that past failures were due to incomplete specification rather than a specific vulnerability of the cells. Midbrain floor plate precursors are derived from hPSCs in days following exposure to small molecule activators of sonic hedgehog (SHH) and canonical WNT signaling. Engraftable midbrain DA neurons are obtained by day 25 and can be maintained in vitro for several months. Extensive in vitro molecular profiling, biochemical and electrophysiological data define developmental progression and confirm identity of hPSC-derived midbrain DA neurons. In vivo survival and function is demonstrated in PD animal models in three host species. Long-term engraftment in 6-OHDA-lesioned mouse and rats demonstrates robust survival of midbrain DA neurons, complete restoration of amphetamine-induced rotation behavior and improvements in tests of forelimb use and akinesia. Finally, scalability is demonstrated by transplantation into Parkinsonian monkeys. Excellent DA neuron survival, function and lack of neural overgrowth in the three animal models tested indicate considerable promise for the development of cell based therapies in PD. Differentiated hESC with three conditions (LSB, LSB/S/F8, LSB/S/F8/CHIR) were subjected to RNA extraction in specific timepoint (day 0, 1, 3, 5, 7, 11, 13, 25) and hybridization on Illumina microarrays. Each sample has 3 or 4 biological repeats. Based on previous study* of dual SMAD inhibition neural induction, we developed new midbrain dopamine neuron protocol. It depends on time specific treatment of below factors (LSB/S/F8/CHIR): L (LDN193189 (BMP inhibitor) , day 0-11), SB (SB431542 (TGF-b signal inhibitor), day 0-5), S (SHH + Purmorphamine (Smo agonist), day 1-7), F8 (FGF8, day 1-7) and CHIR (CHIR99021 (GSK3b inhibitor), day 3-13) LSB and LSB/S/F8 are limited control conditions of dual SMAD only (LSB) or traditional patterning with Sonic and FGF (LSB/S/F8) *Chambers,S.M. et al. Highly efficient neural conversion of human ES and iPS cells by dual inhibition of SMAD signaling. Nat. Biotechnol. 27, 275-280 (2009).
Project description:Human brain development is a complex process involving neural proliferation, differentiation, and migration which are directed by many essential cellular factors and drivers. Here, using the NetBID2 algorithm and developing human brain RNA sequencing(RNA-Seq) dataset, we identified synaptotagmin-like 3(SYTL3) as one of the top drivers of early human brain development. Interestingly, SYTL3 exhibited high activity but low expression in both early developmental human cortex and human embryonic stem cell(hESC)-derived neurons. Knockout of SYTL3(SYTL3 -KO) in human neurons or knockdown of Sytl3 in embryonic mouse cortex markedly promoted neuronal migration. Besides, SYTL3-KO caused an abnormal distribution of deep-layer neurons in brain organoids and reduced presynaptic neurotransmitter release in hESC-derived neurons. We further demonstrated that SYTL3-KO- accelerated neuronal migration was modulated by high expression of matrix metalloproteinases. Together, based on bioinformatics and biological experiments, we identified SYTL3 as a novel regulator of cortical neuronal migration in human and mouse developing brains.
Project description:Development of efficient and reproducible conditions for directed differentiation of pluripotent stem cells into specific cell types is important not only to understand early human development but also to enable more practical applications, such as in vitro models of disease, drug discovery, and cell therapies. The differentiation of stem cells to retinal pigment epithelium (RPE) in particular holds promise as a source of cells for therapeutic replacement in age-related macular degeneration. Here we show development of a robust and efficient method to derive RPE with high reproducibility in an adherent, monolayer system using sequential inhibition and activation of the Activin and BMP signalling pathways. We use whole genome transcript analysis to characterize cells at different stages of differentiation to gain further understanding of the developmental dynamics and fate specification of RPE.
Project description:Neural crest (NC) cells contribute to the development of many complex tissues. The abnormal development of NC cells accounts for a number of congenital birth defects. Generating NC cells, and more specifically NC subpopulations such as cranial, cardiac, and trunk NC cells from human induced pluripotent stem (iPS) cells and human embryonic stem (ES) cells presents a valuable tool to model and study human NC development and disease. Here we provide a robust, efficient, and reproducible protocol for the differentiation of human iPS and ES cells into NC cells. The protocol has been validated in multiple human pluripotent stem cell lines and yields relatively pure NC cell populations in eight days. The resulting cells can be propagated and retain NC marker expression over multiple passages. The NC cells show proper cell specification and can develop into NC-derived cell lineages including smooth muscle cells, peripheral neurons, and Schwann cells. Additionally, the NC cells are functional and migrate to appropriate chemoattractants such as SDF-1, Fgf8b, BMP2, and Wnt3a. Importantly, this method generates all NC subpopulations (cranial, cardiac, and trunk) providing a great advantage to readily available NC differentiation methods. Neural crest cells derived from human induced pluripotent stem cells were profiled using Affymetrix Gene 1.0 arrays to identify differential gene expression changes and alternative exons from the open-source software AltAnalyze. An FDR adjusted emperical Bayes moderated t-test p < 0.05 was used to identify differentially expressed Ensembl genes and GO-Elite used to identify biologically relevant, Ontology, pathway and gene-set categories. Alternative exons were obtained using the FIRMA analysis option and default thresholds. Other array neural crest array and RNA-Seq dataset were compared to this to identify common and distinct regulatory mechanisms.