Project description:Underdeveloped lungs are the primary cause of death in premature infants, however, little is known about stem and progenitor cell maintenance during human lung development. In this study, we have identified that FGF7, Retinoic Acid and CHIR-99021, a small molecule that inhibits GSK3 to activate Wnt signaling, support in vitro maintenance of primary human fetal lung bud tip progenitor cells in a progenitor state. Furthermore, these factors are sufficient to derive a population of human bud tip-like progenitor cells in 3D organoid structures from human pluripotent stem cells (hPSC). Functional studies showed that hPSC-derived bud tip progenitor organoids do not contain any mesenchymal cell types, maintain multilineage potential in vitro and are able to engraft into the airways of injured mice and respond to systemic factors. We performed RNA-sequencing to assess the degree of similarity in global gene expression profiles between the full human fetal lung (59-127 days gestation), isolated human fetal bud tip progenitors, organoids grown from primary fetal bud tip progenitors, and hPSC-derived bud tip organoids. Results showed that hPSC-derived organoids have molecular profiles similar to organoids generated from primary human fetal lung tissue. Gene expression differences between hPSC-derived bud tip organoids and fetal progenitor organoids may be related to the presence of contaminating mesenchymal cells in primary cultures. hPSC-derived bud tip organoids are generated from a well-defined human cell sources, offering a distinct advantage over rare primary tissue as a means to study human specific lung development, homeostasis and disease.<br>Sample Nomenclature - Description<br> -------------------------------------------------------------------------<br> Peripheral fetal lung the distal/peripheral portion of the fetal lung (i.e., distal 0.5 cm) was excised from the rest of the lung using a scalpel. This includes all components of the lung (e.g., epithelial, mesenchymal, vascular). <br>Isolated fetal bud tip the bud peripheral portion of the fetal lung was excised with a scalpel and subjected to enzymatic digestion and microdissection. The epithelium was dissected and separated from the mesenchyme, but a small amount of associated mesenchyme likely remained. <br>Fetal progenitor organoid 3D organoid structures that arose from culturing isolated fetal epithelial bud tips. <br>Foregut spheroid 3D foregut endoderm structure as described in Dye et al. (2015). Gives rise to patterned lung organoid (PLO) when grown in 3F medium. <br> Patterned lung organoid (PLO) lung organoids that were generated by differentiating hPSCs, as described throughout the manuscript. <br> Bud tip organoid organoids derived from PLOs, enriched for SOX2/SOX9 co-expressing cells, and grown/passaged in 3F medium.
Project description:Use of single-cell transcriptomics to test early HD selective vulnerability by comparing CTRL and HD telencephalic organoids at day 45 and 120 of differentiation. To test the influence and the interactions between healthy and HD cells, chimeric organoids composed of CTRL and HD cells juxtaposed within the same organoid were grown and analyzed by scRNAseq at day 120.
Project description:Huntington's disease (HD) causes selective degeneration of striatal and cortical neurons, resulting in cell mosaicism of coexisting still functional and dysfunctional cells. The impact of non-cell autonomous mechanisms between these cellular states is poorly understood. Here we generated telencephalic organoids with healthy or HD cells, grown separately or as mosaics of the two genotypes. We used single-cell transcriptomics to test early HD selective cellular phenotypes by comparing healthy (CTRL) and pathologic (HD) telencephalic organoids at days 45 and 120 of differentiation. To test the influence and the interactions between healthy and HD cells, mosaic organoids composed of CTRL and HD cells juxtaposed within the same organoid were grown and analyzed by scRNAseq at day 120. Single-cell RNA sequencing revealed neurodevelopmental abnormalities in the ventral fate acquisition of HD organoids, confirmed by cytoarchitectural and transcriptional defects leading to fewer GABAergic neurons, while dorsal populations showed milder phenotypes mainly in the maturation trajectory. Healthy cells in mosaic organoids restored HD cell identity, trajectories, synaptic density, and communication pathways upon cell-cell contact while showing no significant alterations when grown with HD cells. These findings highlight cell-type-specific alterations in HD and beneficial non-cell autonomous effects of healthy cells, emphasizing the therapeutic potential of modulating cell-cell communication in disease progression and treatment.
Project description:Striato nigral circuit is composed of medium spiny neuronal projections that were mainly sent from striatum to midbrain substantial nigra (SN), which is essential for regulating motor behaviors. Dysfunction of striato-nigral circuitry may cause a series of motor disabilities which are associated with neurodegenerative disorders, such as Huntington disease (HD). Although the etiology of HD is known as abnormally expanded CAG repeats of the huntingtin gene (HTT), treatment of HD remains tremendous challenges. One possible reason is lack of effective HD model which resembles striato nigral circuitry deficits for the pharmacology studies. Here we first differentiate striatum-like organoids from human pluripotent stem cells, containing functional medium spiny neurons (MSN). We then generated 3D striato nigral circuitoids by assembling striatum-like organoids with midbrain substantial nigra like organoids. With AVV hSYN GFP viral tracing, the extensive MSN projections from striatum to SN are established, which form synaptic connection with dopaminergic neurons and showed the electronic field potentials by labeling striatum like organoids with optogenetic virus. Furthermore, this striato nigral circuitoids exhibited improved calcium activity than individual striatal organoids. Importantly, we further demonstrated the reciprocal projection defects of the HD iPSC derived circuitoids, which could be reversed with the treatment of brain derived nerve factors. Altogether, the striato nigral circuitoids could be used for identifying MSN projection defects, which would be applied as a potential drug test platform for HD.
Project description:Aberrant localization of proteins to mitochondria disturbs mitochondrial function and contributes to the pathogenesis of Huntington’s disease (HD). However, the crucial factors and the molecular mechanisms remain elusive. Here, we found that heat shock transcription factor 1 (HSF1) accumulates in the mitochondria of HD cell cultures, a YAC128 mouse model, and human striatal organoids derived from HD induced pluripotent stem cells (iPSCs). Overexpression of mitochondria-targeting HSF1 (mtHSF1) in the striatum causes neurodegeneration and HD-like behavior. Mechanistically, mtHSF1 facilitates mitochondrial fission by activating dynamin-related protein 1 (Drp1) phosphorylation at S616. Moreover, mtHSF1 suppresses single-stranded DNA binding protein 1 (SSBP1) oligomer formation, which results in mitochondrial DNA (mtDNA) deletion. Suppression of HSF1 mitochondrial localization by DH1, a unique peptide inhibitor, abolishes HSF1-induced mitochondrial abnormalities and ameliorates deficits in an HD animal model and human striatal organoids. Altogether, our findings describe an unsuspected role of HSF1 in contributing to mitochondrial dysfunction, which may provide a promising therapeutic target for HD.
Project description:Introduction of Hermansky-Pudlak Syndrome-associated mutations with CRISPR/Cas9 genome editing, allows for disease modeling in 3D cultures of hPSC-derived lung organoids.
Project description:Pathogenic mutations in alpha kinase 3 (ALPK3) cause cardiomyopathy and a range of musculoskeletal defects. How ALPK3 mutations result in disease remains unclear and little is known about this atypical kinase. Using a suite of engineered human pluripotent stem cells (hPSCs) we show that ALPK3 localizes to the sarcomere, specifically at the M-Band. Both sarcomeric organization and calcium kinetics were disrupted in ALPK3 deficient hPSC derived cardiomyocytes. Further, cardiac organoids derived from ALPK3 knockout hPSCs displayed reduced force generation. Phosphoproteomic profiling of wildtype and ALPK3 null hPSC derived cardiomyocytes revealed ALPK3-dependant phospho-peptides were enriched for proteins involved in sarcomere function and protein quality control. We demonstrate that ALPK3 binds to the selective autophagy receptor SQSTM1 (Sequestome 1) and is required for the sarcomeric localization of SQSTM1. We propose that ALPK3 is a myogenic kinase with an integral role in the intracellular signaling networks underlying sarcomere maintenance required for continued cardiac contractility.
Project description:Pathogenic mutations in alpha kinase 3 (ALPK3) cause cardiomyopathy and a range of musculoskeletal defects. How ALPK3 mutations result in disease remains unclear and little is known about this atypical kinase. Using a suite of engineered human pluripotent stem cells (hPSCs) we show that ALPK3 localizes to the sarcomere, specifically at the M-Band. Both sarcomeric organization and calcium kinetics were disrupted in ALPK3 deficient hPSC derived cardiomyocytes. Further, cardiac organoids derived from ALPK3 knockout hPSCs displayed reduced force generation. Phosphoproteomic profiling of wildtype and ALPK3 null hPSC derived cardiomyocytes revealed ALPK3-dependant phospho-peptides were enriched for proteins involved in sarcomere function and protein quality control. We demonstrate that ALPK3 binds to the selective autophagy receptor SQSTM1 (Sequestome 1) and is required for the sarcomeric localization of SQSTM1. We propose that ALPK3 is a myogenic kinase with an integral role in the intracellular signaling networks underlying sarcomere maintenance required for continued cardiac contractility.
Project description:We constructed aquantitative calculation system (organ-specific panels and calculation algorithm) to assess thesimilarity to the human lung, stomach, and heart and confirmed the algorithm using in-houseRNA-seq data (total RNA from 20 tissues). To evaluate our system, we generated hPSC-derived lung organoids, gastric organoids, and cardiomyocytes and detected 33.4%, 51.7%, and 83.4% similarity, respectively, to the corresponding human target organs.