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

Motor neuron diseases (MNDs) are a group of neurological disorders that selectively affect motor neurons. There are currently no cures or efficacious treatments for these diseases. In recent years,significant developments in stem cell research have been applied to MNDs,particularly regarding neuroprotection and cell replacement. However,a consistent source of motor neurons for cell replacement is required. Human embryonic stem cells (hESCs) could provide an inexhaustible supply of differentiated cell types,including motor neurons that could be used for MND therapies. Recently,it has been demonstrated that induced pluripotent stem (iPS) cells may serve as an alternative source of motor neurons,since they share ES characteristics,self-renewal,and the potential to differentiate into any somatic cell type. In this review,we discuss several reproducible methods by which hESCs or iPS cells are efficiently isolated and differentiated into functional motor neurons,and possible clinical applications. View Publication

Human embryonic stem cells (hESCs) have the potential to generate multiple cell types and hold promise for future therapeutic applications. Although undifferentiated hESCs can proliferate indefinitely,hESC derivatives significantly downregulate telomerase and have limited replication potential. In this study we examine whether the replicative lifespan of hESC derivatives can be extended by ectopic expression of human telomerase reverse transcriptase (hTERT),the catalytic component of the telomerase complex. To this end,we have derived HEF1 cells,a fibroblast-like cell type,differentiated from hESCs. Infection of HEF1 cells with a retrovirus expressing hTERT extends their replicative capacity,resulting in immortal human HEF1-hTERT cells. HEF1-hTERT cells can be used to produce conditioned medium (CM) capable of supporting hESC growth under feeder-free conditions. Cultures maintained in HEF1-CM show characteristics similar to mouse embryonic fibroblast CM control cultures,including morphology,surface marker and transcription factor expression,telomerase activity,differentiation,and karyotypic stability. In addition,HEF1-hTERT cells have the capacity to differentiate into cells of the osteogenic lineage. These results suggest that immortalized cell lines can be generated from hESCs and that cells derived from hESCs can be used to support their own growth,creating a genotypically homogeneous system for the culture of hESCs. View Publication

Cardiovascular progenitor cells (CVPCs) derived from human embryonic stem cells and human induced pluripotent stem cells represent an invaluable potential source for the study of early embryonic cardiovascular development and stem cell-based therapies for congenital and acquired heart diseases. To fully realize their values,it is essential to establish an efficient and stable differentiation system for the induction of these pluripotent stem cells (PSCs) into the CVPCs and robustly expand them in culture,and then further differentiate these CVPCs into multiple cardiovascular cell types. Here we describe the protocols for efficient derivation,expansion,and differentiation of CVPCs from hPSCs in a chemically defined medium under feeder- and serum-free culture conditions. View Publication

Peripheral blood is the easy-to-access,minimally invasive,and the most abundant cell source to use for cell reprogramming. The episomal vector is among the best approaches for generating integration-free induced pluripotent stem (iPS) cells due to its simplicity and affordability. Here we describe the detailed protocol for the efficient generation of integration-free iPS cells from peripheral blood mononuclear cells. With this optimized protocol,one can readily generate hundreds of iPS cell colonies from 1 ml of peripheral blood. View Publication

Transfer of therapeutic genes to human hematopoietic stem cells (HSCs) using complex vectors at clinically relevant efficiencies remains a major challenge. Recently we described a stable retroviral vector that sustains long-term expression of green fluorescent protein (GFP) and a human beta-globin gene in the erythroid progeny of transduced murine HSCs. We now report the efficient transduction of primitive human CD34(+) fetal liver or cord blood cells with this vector and expression of the beta-globin transgene in the erythroid progeny of these human cells for at least 2 months. After growth factor prestimulation and then a 2- to 3-day exposure to the virus,35% to 55% GFP(+) progeny were seen in assays of transduced colony-forming cells,primitive erythroid precursors that generate large numbers of glycophorin A(+) cells in 3-week suspension cultures,and 6-week long-term culture-initiating cells. In immunodeficient mice injected with unselected infected cells,5% to 15% of the human cells regenerated in the marrow (including the erythroid cells) were GFP(+) 3 and 6 weeks after transplantation. Importantly,the numbers of GFP(+) human lymphoid and either granulopoietic or erythroid cells in individual mice 6 weeks after transplantation were significantly correlated,indicative of the initial transduction of human multipotent cells with in vivo repopulating activity. Expression of the transduced beta-globin gene in human cells obtained directly from the mice or after their differentiation into erythroid cells in vitro was demonstrated by reverse transcriptase-polymerase chain reaction using specific primers. These experiments represent a significant step toward the realization of a gene therapy approach for human beta-globin gene disorders. View Publication

BackgroundSeveral approaches are being explored for engineering off-the-shelf chimeric antigen receptor (CAR) T cells. In this study,we engineered chimeric Fcγ receptor (FcγR) T cells and tested their potential as a versatile platform for universal T cell therapy.MethodsChimeric FcγR (CFR) constructs were generated using three distinct forms of FcγR,namely CD16A,CD32A,and CD64. The functionality of CFR T cells was evaluated through degranulation assays,specific target lysis experiments,in vitro cytokine production analysis,and assessment of tumor xenograft destruction specificity in mouse models using different monoclonal antibodies (MoAbs).ResultsThree types of CFR T cells were engineered,16s3,32-8a,64-8a CFR T cells. In the presence of rituximab (RTX),cytotoxicity of all three types of CFR T cells against CD20+ Raji-wt,K562-CD20+,and primary tumor cells was significantly higher than that of the mock T cells (P < 0.001). When herceptin was used,all three types of CFR T cells exhibited significant cytotoxicity against HER2+ cell lines of SK-BR-3,SK-OV-3,and HCC1954 (P < 0.001). The cytotoxicity of 64-8a CFR T cells was significantly inhibited by free human IgG at a physiological dose (P < 0.001),which was not observed in 16s3,32-8a CFR T cells. Compared to 32-8a CFR T cells,16s3 CFR T cells exhibited more prolonged cytotoxicity than 32-8a CFR T cells (P < 0.01). In in vivo assays using xenograft models,16s3 CFR T cells significantly prolonged the survival of mice xenografted with Raji-wt cells in the presence of RTX (P < 0.001),and effectively reduced tumor burden in mice xenografted with SK-OV-3 cells in the presence of herceptin (P < 0.05). No significant non-specific cytotoxicity of CFR T cells was found in vivo.ConclusionThe anti-tumor effects of the CFR T cells in vitro and in xenograft mouse models are mediated by specific MoAbs such as RTX and herceptin. The CFR T cells therefore have the features of universal T cells with specificity directed by MoAbs. 16s3 CFR T cells are chosen for clinical trials.Supplementary InformationThe online version contains supplementary material available at 10.1186/s40164-025-00595-x. View Publication

The $\beta$-haemoglobinopathies,such as sickle cell disease and $\beta$-thalassaemia,are caused by mutations in the $\beta$-globin (HBB) gene and affect millions of people worldwide. Ex vivo gene correction in patient-derived haematopoietic stem cells followed by autologous transplantation could be used to cure $\beta$-haemoglobinopathies. Here we present a CRISPR/Cas9 gene-editing system that combines Cas9 ribonucleoproteins and adeno-associated viral vector delivery of a homologous donor to achieve homologous recombination at the HBB gene in haematopoietic stem cells. Notably,we devise an enrichment model to purify a population of haematopoietic stem and progenitor cells with more than 90{\%} targeted integration. We also show efficient correction of the Glu6Val mutation responsible for sickle cell disease by using patient-derived stem and progenitor cells that,after differentiation into erythrocytes,express adult $\beta$-globin (HbA) messenger RNA,which confirms intact transcriptional regulation of edited HBB alleles. Collectively,these preclinical studies outline a CRISPR-based methodology for targeting haematopoietic stem cells by homologous recombination at the HBB locus to advance the development of next-generation therapies for $\beta$-haemoglobinopathies. View Publication

Activation of thermogenic beige adipocytes has recently emerged as a promising therapeutic target in obesity and diabetes. Relevant human models for beige adipocyte differentiation are essential to implement such therapeutic strategies. We report a straightforward and efficient protocol to generate functional human beige adipocytes from human induced pluripotent stem cells (hiPSCs). Without overexpression of exogenous adipogenic genes,our method recapitulates an adipogenic developmental pathway through successive mesodermal and adipogenic progenitor stages. hiPSC-derived adipocytes are insulin sensitive and display beige-specific markers and functional properties,including upregulation of thermogenic genes,increased mitochondrial content,and increased oxygen consumption upon activation with cAMP analogs. Engraftment of hiPSC-derived adipocytes in mice produces well-organized and vascularized adipose tissue,capable of β-adrenergic-responsive glucose uptake. Our model of human beige adipocyte development provides a new and scalable tool for disease modeling and therapeutic screening. View Publication

Human Embryonic Stem Cells (hESC) offer an important resource as a limitless supply of any differentiated cell type of the human body. Keratocytes,cells from the corneal stroma,may have the potential for restoration of vision in cell therapy and biomedical engineering applications,but these specialized cells are not readily expanded in vitro. Here we describe a two-part method to produce keratocytes from the H1 hESC cell line. The hESC cells,maintained and expanded in feeder-free culture medium are first differentiated to neural crest cells using the stromal-derived inducing activity (SDIA) of the PA6 mouse embryonic fibroblast cell line. The resulting neural crest cells are selected by their expression of cell-surface CD271 and subsequently cultured as 3D pellets in a defined differentiation medium to induce a keratocyte phenotype. View Publication

Defined transcription factors can induce epigenetic reprogramming of adult mammalian cells into induced pluripotent stem cells. Although DNA factors are integrated during some reprogramming methods,it is unknown whether the genome remains unchanged at the single nucleotide level. Here we show that 22 human induced pluripotent stem (hiPS) cell lines reprogrammed using five different methods each contained an average of five protein-coding point mutations in the regions sampled (an estimated six protein-coding point mutations per exome). The majority of these mutations were non-synonymous,nonsense or splice variants,and were enriched in genes mutated or having causative effects in cancers. At least half of these reprogramming-associated mutations pre-existed in fibroblast progenitors at low frequencies,whereas the rest occurred during or after reprogramming. Thus,hiPS cells acquire genetic modifications in addition to epigenetic modifications. Extensive genetic screening should become a standard procedure to ensure hiPS cell safety before clinical use. View Publication

Deficiency of the nuclear factor-kappa-B essential modulator (NEMO) is a rare X-linked disorder that presents in boys as hypohydrotic ectodermal dysplasia with immunodeficiency due to defective nuclear factor-κB activation. Here we report on the generation of 2 human embryonic stem cell lines from discarded in vitro fertilization (IVF) embryos ascertained via preimplantation genetic diagnosis. We have derived two human embryonic stem cell lines that carry a T458G hypomorphic mutation in exon 4 of the NEMO (or IKBKG) gene. One of the lines is diploid male; the other is diploid female but has clonally inactivated the X-chromosome that harbors the wild-type IKBKG gene. We show that both lines are pluripotent,have the capacity to differentiate into hematopoietic progenitors,and have defective inhibitor of nuclear factor kappa-B kinase activity. These NEMO deficiency hES cell lines provide an unlimited source for differentiated cell types and may serve as a unique tool to study NEMO deficiency and potentially lead to the development of new therapies for this disease. View Publication

The processes that govern human haematopoietic stem cell (HSC) self-renewal and engraftment are poorly understood and challenging to recapitulate in culture to reliably expand functional HSCs 1 – 3 . Here we identify MYC target 1 (MYCT1; also known as MTLC) as a crucial human HSC regulator that moderates endocytosis and environmental sensing in HSCs. MYCT1 is selectively expressed in undifferentiated human haematopoietic stem and progenitor cells (HSPCs) and endothelial cells but becomes markedly downregulated during HSC culture. Lentivirus-mediated knockdown of MYCT1 prevented human fetal liver and cord blood (CB) HSPC expansion and engraftment. By contrast,restoring MYCT1 expression improved the expansion and engraftment of cultured CB HSPCs. Single-cell RNA sequencing of human CB HSPCs in which MYCT1 was knocked down or overexpressed revealed that MYCT1 governs important regulatory programmes and cellular properties essential for HSC stemness,such as ETS factor expression and low mitochondrial activity. MYCT1 is localized in the endosomal membrane in HSPCs and interacts with vesicle trafficking regulators and signalling machinery. MYCT1 loss in HSPCs led to excessive endocytosis and hyperactive signalling responses,whereas restoring MYCT1 expression balanced culture-induced endocytosis and dysregulated signalling. Moreover,sorting cultured CB HSPCs on the basis of lowest endocytosis rate identified HSPCs with preserved MYCT1 expression and MYCT1-regulated HSC stemness programmes. Our work identifies MYCT1-moderated endocytosis and environmental sensing as essential regulatory mechanisms required to preserve human HSC stemness. Our data also pinpoint silencing of MYCT1 as a cell-culture-induced vulnerability that compromises human HSC expansion. Subject terms: Haematopoietic stem cells,Self-renewal,Stem-cell niche,Endocytosis,Growth factor signalling View Publication