搜索结果: 'methocult media formulations for human hematopoietic cells serum containing'

The enteric nervous system (ENS) of the gastrointestinal tract controls many diverse functions,including motility and epithelial permeability. Perturbations in ENS development or function are common,yet there is no human model for studying ENS-intestinal biology and disease. We used a tissue-engineering approach with embryonic and induced pluripotent stem cells (PSCs) to generate human intestinal tissue containing a functional ENS. We recapitulated normal intestinal ENS development by combining human-PSC-derived neural crest cells (NCCs) and developing human intestinal organoids (HIOs). NCCs recombined with HIOs in vitro migrated into the mesenchyme,differentiated into neurons and glial cells and showed neuronal activity,as measured by rhythmic waves of calcium transients. ENS-containing HIOs grown in vivo formed neuroglial structures similar to a myenteric and submucosal plexus,had functional interstitial cells of Cajal and had an electromechanical coupling that regulated waves of propagating contraction. Finally,we used this system to investigate the cellular and molecular basis for Hirschsprung's disease caused by a mutation in the gene PHOX2B. This is,to the best of our knowledge,the first demonstration of human-PSC-derived intestinal tissue with a functional ENS and how this system can be used to study motility disorders of the human gastrointestinal tract. View Publication

The glycoprotein hormone erythropoietin regulates the level of oxygen in the blood by modulating the number of circulating erythrocytes,and is produced in the kidney or liver of adult and the liver of fetal or neonatal mammals. Neither the precise cell types that produce erythropoietin nor the mechanisms by which the same or different cells measure the circulating oxygen concentration and consequently regulate erythropoietin production are known. Cells responsive to erythropoietin have been identified in the adult bone marrow,fetal liver or adult spleen. In cultures of erythropoietic progenitors,erythropoietin stimulates proliferation and differentiation to more mature red blood cells. Detailed molecular studies have been hampered,however,by the impurity and heterogeneity of target cell populations and the difficulty of obtaining significant quantities of the purified hormone. Highly purified erythropoietin may be useful in the treatment of various forms of anaemia,particularly in chronic renal failure. Here we describe the cloning of the human erythropoietin gene and the expression of an erythropoietin cDNA clone in a transient mammalian expression system to yield a secreted product with biological activity. View Publication

Many forms of blindness result from the dysfunction or loss of retinal photoreceptors. Induced pluripotent stem cells (iPSCs) hold great potential for the modelling of these diseases or as potential therapeutic agents. However,to fulfill this promise,a remaining challenge is to induce human iPSC to recreate in vitro key structural and functional features of the native retina,in particular the presence of photoreceptors with outer-segment discs and light sensitivity. Here we report that hiPSC can,in a highly autonomous manner,recapitulate spatiotemporally each of the main steps of retinal development observed in vivo and form three-dimensional retinal cups that contain all major retinal cell types arranged in their proper layers. Moreover,the photoreceptors in our hiPSC-derived retinal tissue achieve advanced maturation,showing the beginning of outer-segment disc formation and photosensitivity. This success brings us one step closer to the anticipated use of hiPSC for disease modelling and open possibilities for future therapies. View Publication

Dysregulated neurodevelopment with altered structural and functional connectivity is believed to underlie many neuropsychiatric disorders,and /`a disease of synapses/' is the major hypothesis for the biological basis of schizophrenia. Although this hypothesis has gained indirect support from human post-mortem brain analyses and genetic studies,little is known about the pathophysiology of synapses in patient neurons and how susceptibility genes for mental disorders could lead to synaptic deficits in humans. Genetics of most psychiatric disorders are extremely complex due to multiple susceptibility variants with low penetrance and variable phenotypes. Rare,multiply affected,large families in which a single genetic locus is probably responsible for conferring susceptibility have proven invaluable for the study of complex disorders. Here we generated induced pluripotent stem (iPS) cells from four members of a family in which a frameshift mutation of disrupted in schizophrenia 1 (DISC1) co-segregated with major psychiatric disorders and we further produced different isogenic iPS cell lines via gene editing. We showed that mutant DISC1 causes synaptic vesicle release deficits in iPS-cell-derived forebrain neurons. Mutant DISC1 depletes wild-type DISC1 protein and,furthermore,dysregulates expression of many genes related to synapses and psychiatric disorders in human forebrain neurons. Our study reveals that a psychiatric disorder relevant mutation causes synapse deficits and transcriptional dysregulation in human neurons and our findings provide new insight into the molecular and synaptic etiopathology of psychiatric disorders. View Publication

Recent breakthroughs in 3-dimensional (3D) organoid cultures for many organ systems have led to new physiologically complex in vitro models to study human development and disease. Here,we report the step-wise differentiation of human pluripotent stem cells (hPSCs) (embryonic and induced) into lung organoids. By manipulating developmental signaling pathways hPSCs generate ventral-anterior foregut spheroids,which are then expanded into human lung organoids (HLOs). HLOs consist of epithelial and mesenchymal compartments of the lung,organized with structural features similar to the native lung. HLOs possess upper airway-like epithelium with basal cells and immature ciliated cells surrounded by smooth muscle and myofibroblasts as well as an alveolar-like domain with appropriate cell types. Using RNA-sequencing,we show that HLOs are remarkably similar to human fetal lung based on global transcriptional profiles,suggesting that HLOs are an excellent model to study human lung development,maturation and disease. View Publication

Increased dosage of methyl-CpG-binding protein-2 (MeCP2) results in a dramatic neurodevelopmental phenotype with onset at birth. We generated induced pluripotent stem cells (iPSCs) from patients with the MECP2 duplication syndrome (MECP2dup),carrying different duplication sizes,to study the impact of increased MeCP2 dosage in human neurons. We show that cortical neurons derived from these different MECP2dup iPSC lines have increased synaptogenesis and dendritic complexity. In addition,using multi-electrodes arrays,we show that neuronal network synchronization was altered in MECP2dup-derived neurons. Given MeCP2 functions at the epigenetic level,we tested whether these alterations were reversible using a library of compounds with defined activity on epigenetic pathways. One histone deacetylase inhibitor,NCH-51,was validated as a potential clinical candidate. Interestingly,this compound has never been considered before as a therapeutic alternative for neurological disorders. Our model recapitulates early stages of the human MECP2 duplication syndrome and represents a promising cellular tool to facilitate therapeutic drug screening for severe neurodevelopmental disorders. View Publication

Transplantation of Defined Populations of Differentiated Human Neural Stem Cell Progeny View Publication

Precise gene editing uncovers mis-splicing of BUBR1 and CDC27 in human SF3B1-mutant HSPCs,leading to activation of mitotic checkpoint and rendering the cells sensitive to CHK1 inhibitor prexasertib. View Publication

CD38,an ecto-enzyme involved in NAD + catabolism,is highly expressed in exhausted CD8 + T cells and has emerged as an attractive target to improve response to immune checkpoint blockade (ICB) by blunting T cell exhaustion. However,the precise role(s) and regulation of CD38 in exhausted T cells and the efficacy of CD38-directed therapeutic strategies in human cancer remain incompletely defined. Here,we show that CD38 + CD8 + T cells are induced by chronic TCR activation and type I interferon stimulation and confirm their association with ICB resistance in human melanoma. Disrupting CD38 restores cellular NAD + pools and improves T cell bioenergetics and effector functions. Targeting CD38 restores ICB sensitivity in a cohort of patient-derived organotypic tumor spheroids from explanted melanoma specimens. These results support further preclinical and clinical evaluation of CD38-directed therapies in melanoma and underscore the importance of NAD + as a vital metabolite to enhance those therapies. View Publication