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:We have generated expression profiles of three different neural crest populations from human embryonic stem cells. These profiles were compared to a neuroectoderm population. We find that the neural crest populations are separable and distinct. All cell types were differentiated from human embryonic stem cells. Neural crest populations were sorted on day 12 for CD49. The neuroectoderm cells were unsorted and harvested on day 12 of differentiation.
Project description:We have generated expression profiles of three different neural crest populations from human embryonic stem cells. These profiles were compared to a neuroectoderm population. We find that the neural crest populations are separable and distinct.
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: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.
Project description:The neural crest (NC) is a transient dynamic structure of ectodermal origin, found in early vertebrate embryos. The multipotential NC cells migrate along well defined routes, differentiate to various cells types including melanocytes and participate in the formation of various permanent tissues. Abnormal development of NC cells causes several human diseases M-bM-^@M-^S neurocristopathies. As there is only limited information about the molecular mechanisms controlling early events in melanocyte specification and development, we exploited the AMV v-Myb transcriptional regulator, which directs differentiation of in vitro chicken NC cells to the melanocyte lineage. This activity is strictly dependent on v-Myb specifically binding to the Myb recognition DNA element (MRE). The two tamoxifen-inducible v-myb alleles were constructed, one which recognizes the MRE and one which does not. These were activated in ex-ovo NC cells, and the expression profiles of resulting cells were analyzed using Affymetrix microarrays and RT-PCR. These approaches revealed up-regulation of the BMP antagonist gremlin 2 mRNA, and down-regulation of mRNAs encoding several epithelial genes including KRT19 as very early events following the activation of melanocyte differentiation by v-Myb. Comparison of gene expression profiles of chicken neural crest cells constitutively expressing 4-OH-tamoxifen inducible v-myb with mutated leucine zipper region or a version with an additional point mutation (N118D) in the DNA-binding domain. Three biological replicates were analyzed for each group.
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.
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.
Project description:Glial cells have been proposed as an endogenous source of progenitors for the treatment of neural deficits. However, the cellular and molecular mechanisms underpinning the neurogenic potential of certain populations of adult glial cells, are not known. Using single cell transcriptomic profiling, we show here that enteric glial cells represent a cell state attained by autonomic neural crest cells as they transition during development along a linear default differentiation trajectory that allows them to retain neurogenic potential while acquiring a gene expression profile associated with their role in neuronal support and immunomodulation. Key neurogenic loci in early enteric nervous system progenitors remain in open chromatin configuration in mature enteric glia, thus facilitating neuronal differentiation under appropriate conditions. Molecular profiling and gene targeting of enteric glial cells in a novel cell culture system of enteric neurogenesis and a gut injury model, demonstrated that neuronal differentiation of glia is driven by transcriptional programs employed in vivo by early progenitors. Our work provides mechanistic insight into the dynamic regulatory landscape underpinning the development of intestinal neural circuits and generates a platform for advancing glial cells as therapeutic agents for the treatment of neural deficits.
Project description:Glial cells have been proposed as an endogenous source of progenitors for the treatment of neural deficits. However, the cellular and molecular mechanisms underpinning the neurogenic potential of certain populations of adult glial cells, are not known. Using single cell transcriptomic profiling, we show here that enteric glial cells represent a cell state attained by autonomic neural crest cells as they transition during development along a linear default differentiation trajectory that allows them to retain neurogenic potential while acquiring a gene expression profile associated with their role in neuronal support and immunomodulation. Key neurogenic loci in early enteric nervous system progenitors remain in open chromatin configuration in mature enteric glia, thus facilitating neuronal differentiation under appropriate conditions. Molecular profiling and gene targeting of enteric glial cells in a novel cell culture system of enteric neurogenesis and a gut injury model, demonstrated that neuronal differentiation of glia is driven by transcriptional programs employed in vivo by early progenitors. Our work provides mechanistic insight into the dynamic regulatory landscape underpinning the development of intestinal neural circuits and generates a platform for advancing glial cells as therapeutic agents for the treatment of neural deficits.