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

Patients with Fanconi anemia (FA) have a high risk of developing acute myeloid leukemia (AML). In this study,we attempted to identify cell-surface markers for leukemia-initiating cells in FA-AML patients. We found that the IL-3 receptor-α (IL-3Rα) is a promising candidate as an leukemia-initiating cell-specific antigen for FA-AML. Whereas IL-3Rα expression is undetectable on normal CD34(+)CD38(-) HSCs,it is overexpressed on CD34(+)CD38(-) cells from FA patients with AML. We examined the leukemia-initiating cell activity of IL-3Rα-positive FA-AML cells in a humanized" FA xenotransplant model in which we separated AML cells into IL-3Rα-positive and IL-3Rα-negative CD34 fractions and transplanted them into irradiated recipient mice. In all 3 FA-AML samples� View Publication

The mouse trachea is thought to contain two distinct stem cell compartments that contribute to airway repair-basal cells in the surface airway epithelium (SAE) and an unknown submucosal gland (SMG) cell type. Whether a lineage relationship exists between these two stem cell compartments remains unclear. Using lineage tracing of glandular myoepithelial cells (MECs),we demonstrate that MECs can give rise to seven cell types of the SAE and SMGs following severe airway injury. MECs progressively adopted a basal cell phenotype on the SAE and established lasting progenitors capable of further regeneration following reinjury. MECs activate Wnt-regulated transcription factors (Lef-1/TCF7) following injury and Lef-1 induction in cultured MECs promoted transition to a basal cell phenotype. Surprisingly,dose-dependent MEC conditional activation of Lef-1 in vivo promoted self-limited airway regeneration in the absence of injury. Thus,modulating the Lef-1 transcriptional program in MEC-derived progenitors may have regenerative medicine applications for lung diseases. View Publication

The transplantation of spinal cord progenitor cells (SCPCs) derived from human-induced pluripotent stem cells (iPSCs) has beneficial effects in treating spinal cord injury (SCI). However,the presence of residual undifferentiated iPSCs among their differentiated progeny poses a high risk as these cells can develop teratomas or other types of tumors post-transplantation. Despite the need to remove these residual undifferentiated iPSCs,no specific surface markers can identify them for subsequent removal. By profiling the size of SCPCs after a 10-day differentiation process,we found that the large-sized group contains significantly more cells expressing pluripotent markers. In this study,we used a sized-based,label-free separation using an inertial microfluidic-based device to remove tumor-risk cells. The device can reduce the number of undifferentiated cells from an SCPC population with high throughput (ie,>3 million cells/minute) without affecting cell viability and functions. The sorted cells were verified with immunofluorescence staining,flow cytometry analysis,and colony culture assay. We demonstrated the capabilities of our technology to reduce the percentage of OCT4-positive cells. Our technology has great potential for the “downstream processing” of cell manufacturing workflow,ensuring better quality and safety of transplanted cells. View Publication

Adipose-derived stromal cells (ASCs) possess significant regenerative potential,playing a key role in tissue repair and angiogenesis. During wound healing,ASC interacts with the extracellular matrix by recognizing arginylglycylaspartic acid (RGD) motifs,which are crucial for mediating these functions. This study investigates how RGD exposure influences ASC behavior,with a focus on angiogenesis. To mimic the wound-healing environment,ASC were cultured in a porcine gelatin sponge,an RGD-exposing matrix. Transcriptomics revealed that ASC cultured in gelatin exhibited an upregulated expression of genes associated with inflammation,angiogenesis,and tissue repair compared to ASC in suspension. Pro-inflammatory and pro-angiogenic factors,including IL-1,IL-6,IL-8,and VEGF,were significantly elevated. Functional assays further demonstrated that ASC-conditioned media enhanced endothelial cell migration,tubulogenesis,and reduced endothelial permeability,all critical processes in angiogenesis. Notably,ASC-conditioned media also promoted vasculogenesis in human vascular organoids. The inhibition of ASC-RGD interactions using the cyclic peptide cilengitide reversed these effects,underscoring the essential role of RGD-integrin interactions in ASC-mediated angiogenesis. These findings suggest that gelatin sponges enhance ASC’s regenerative and angiogenic properties via RGD-dependent mechanisms,offering promising therapeutic potential for tissue repair and vascular regeneration. Understanding how RGD modulates ASC behavior provides valuable insights into advancing cell-based regenerative therapies. View Publication

The recent advances,offered by cell therapy in the regenerative medicine field,offer a revolutionary potential for the development of innovative cures to restore compromised physiological functions or organs. Adult myogenic precursors,such as myoblasts or satellite cells,possess a marked regenerative capacity,but the exploitation of this potential still encounters significant challenges in clinical application,due to low rate of proliferation in vitro,as well as a reduced self-renewal capacity. In this scenario,induced pluripotent stem cells (iPSCs) can offer not only an inexhaustible source of cells for regenerative therapeutic approaches,but also a valuable alternative for in vitro modeling of patient-specific diseases. In this study we established a reliable protocol to induce the myogenic differentiation of iPSCs,generated from pericytes and fibroblasts,exploiting skeletal muscle-derived extracellular vesicles (EVs),in combination with chemically defined factors. This genetic integration-free approach generates functional skeletal myotubes maintaining the engraftment ability in vivo. Our results demonstrate evidence that EVs can act as biological shuttles" to deliver specific bioactive molecules for a successful transgene-free differentiation offering new opportunities for disease modeling and regenerative approaches." View Publication

An expansion of the cerebral neocortex is thought to be the foundation for the unique intellectual abilities of humans. It has been suggested that an increase in the proliferative potential of neural progenitors (NPs) underlies the expansion of the cortex and its convoluted appearance. Here we show that increasing NP proliferation induces expansion and folding in an in vitro model of human corticogenesis. Deletion of PTEN stimulates proliferation and generates significantly larger and substantially folded cerebral organoids. This genetic modification allows sustained cell cycle re-entry,expansion of the progenitor population,and delayed neuronal differentiation,all key features of the developing human cortex. In contrast,Pten deletion in mouse organoids does not lead to folding. Finally,we utilized the expanded cerebral organoids to show that infection with Zika virus impairs cortical growth and folding. Our study provides new insights into the mechanisms regulating the structure and organization of the human cortex. View Publication

The type III family of IFNs displays immunomodulatory and antiviral activity. Each member (IFN-lambda1,-2,and -3) signals through the same heterodimeric receptor complex,which consists of the binding and signaling subunit (IL-28Ralpha) plus the IL-10Rbeta chain. Although the receptor has a wide tissue distribution,the direct effects of IFN-lambda on various immune cell subsets have not been fully characterized. We have identified high levels of IL-28Ralpha mRNA in pDC from peripheral blood and hypothesized that IFN-lambda plays an important role in pDC maturation and development. We show that stimulation of pDC with HSV or Imiquimod causes an increase in IL-28Ralpha mRNA. In these cells,IFN-lambda1 alters expression of the costimulatory molecules CD80 and ICOS-L and synergizes with IFN-alpha to up-regulate CD83. In addition,IFN-lambda1 has a variable effect on the homing molecule expression of pDC and mDC. IFN-lambda1-treated pDC display a marked difference in their ability to stimulate production of the signature cytokines IL-13,IFN-gamma,and IL-10 in a MLR. This work characterizes the variable effects of IFN-lambda on DC surface molecule expression and identifies a role in pDC activation and immunostimulatory potential. View Publication

The in vitro differentiation of human embryonic stem cells (hESCs) offers a model system to explore human development. Humans with mutations in the transcription factor Aristaless Related Homeobox (ARX) often suffer from the syndrome X-linked lissencephaly with ambiguous genitalia (XLAG),affecting many cell types including those of the pancreas. Indeed,XLAG pancreatic islets lack glucagon and pancreatic polypeptide-positive cells but retain somatostatin,insulin,and ghrelin-positive cells. To further examine the role of ARX in human pancreatic endocrine development,we utilized genomic editing in hESCs to generate deletions in ARX. ARX knockout hESCs retained pancreatic differentiation capacity and ARX knockout endocrine cells were biased toward somatostatin-positive cells (94% of endocrine cells) with reduced pancreatic polypeptide (rarely detected),glucagon (90% reduced) and insulin-positive (65% reduced) lineages. ARX knockout somatostatin-positive cells shared expression patterns with human fetal and adult $$-cells. Differentiated ARX knockout cells upregulated PAX4,NKX2.2,ISL1,HHEX,PCSK1,PCSK2 expression while downregulating PAX6 and IRX2. Re-expression of ARX in ARX knockout pancreatic progenitors reduced HHEX and increased PAX6 and insulin expression following differentiation. Taken together these data suggest that ARX plays a key role in pancreatic endocrine fate specification of pancreatic polypeptide,somatostatin,glucagon and insulin positive cells from hESCs. View Publication

Although distinct human induced pluripotent stem cell (hiPSC) lines can display considerable epigenetic variation,it has been unclear whether such variability impacts their utility for disease modeling. Here,we show that although low-passage female hiPSCs retain the inactive X chromosome of the somatic cell they are derived from,over time in culture they undergo an erosion" of X chromosome inactivation (XCI). This erosion of XCI is characterized by loss of XIST expression and foci of H3-K27-trimethylation� View Publication

Functional cardiomyocytes can be efficiently derived from human pluripotent stem cells (hPSCs),which collectively include embryonic and induced pluripotent stem cells. This cellular platform presents exciting new opportunities for development of pharmacologically relevant in vitro screens to detect cardiotoxicity,validate novel drug candidates in preclinical trials and understand complex congenital cardiovascular disorders,to advance current clinical therapies. Here,we discuss the progress and impediments the field has faced in using hPSC-derived cardiomyocytes for these in vitro applications,and highlight that rigorous protocol optimisation and standardisation,scalability and automation are remaining obstacles for the generation of pure,mature and clinically relevant hPSC cardiomyocytes. View Publication

Human embryonic stem cells are derived from the inner cell mass of preimplantation embryo at the blastocyst stage and their differentiation occurs through an intermediate step involving the formation of embryoid bodies (EBs),which are aggregates of embryonic stem cells. The EBs seem to be a powerful tool for investigating the development of embryos,as they can mimic the initial stages of embryonic development. In this study,we aimed to investigate the effect of estrogen compounds on the proliferation and differentiation of short-term and long-term cultured EBs in vitro. For this study,10-day-old (short-term cultured) and 30-day-old (long-term cultured) EBs were subjected to estradiol (E2),estriol (E3),selective estrogen receptor modulator (raloxifene [RLX]),bisphenol A,and 1,3,5-tris(4-hydroxyphenyl)-4-propyl-1H-pyrazole for 7 days. To confirm the effects of estrogen treatment,ICI-182780 was added to the respective EBs for additional 7 days following estrogen treatment. Quantitative reverse transcription-polymerase chain reaction was performed to analyze the relative expression of differentiation marker genes representing the 3 germ layers. The expression of 7 marker genes,which included α-fetoprotein,hepatocyte nuclear factor (HNF)-3β,HNF-4α (endoderm),brachyury,cardiac actin ([cACT]; mesoderm),nestin (ectoderm),and Oct-4 (undifferentiated),was measured. Significantly,lower expression of HNF-4α in both short-term and long-term cultured EBs was observed after treatment of estrogen compounds compared to control. The expression of HNF-3β in short-term cultured EBs has been positively affected by E2,E3,and RLX. Regarding cACT,higher expression was observed after treatment of E2 (10(-7) mol/L) and E3 (10(-9) mol/L) in short-term cultured EBs,but opposite effects were demonstrated in long-term cultured EBs. The lower expressions of HNF-4α by E2 and RLX were negated by ICI-182780 treatment,although these findings were not statistically significant in E3-treated group. These findings suggest that estrogen compounds have effects on endodermal and mesodermal differentiation of human EBs. View Publication

The formation of mammalian synapses entails the precise alignment of presynaptic release sites with postsynaptic receptors but how nascent cell–cell contacts translate into assembly of presynaptic specializations remains unclear. Guided by pioneering work in invertebrates,we hypothesized that in mammalian synapses,liprin-? proteins directly link trans-synaptic initial contacts to downstream steps. Here we show that,in human neurons lacking all four liprin-? isoforms,nascent synaptic contacts are formed but recruitment of active zone components and accumulation of synaptic vesicles is blocked,resulting in ‘empty’ boutons and loss of synaptic transmission. Interactions with presynaptic cell adhesion molecules of either the LAR-RPTP family or neurexins via CASK are required to localize liprin-? to nascent synaptic sites. Liprin-? subsequently recruits presynaptic components via a direct interaction with ELKS proteins. Thus,assembly of human presynaptic terminals is governed by a hierarchical sequence of events in which the recruitment of liprin-? proteins by presynaptic cell adhesion molecules is a critical initial step. This paper identifies the evolutionarily conserved liprin-? protein family as key mediators of presynaptic assembly in human neurons. Their recruitment to sites formed by contacting neurons is the critical initial step that triggers presynaptic differentiation. View Publication