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

Human pluripotent stem cells (hPSCs) exist in heterogeneous micro-environments with multiple subpopulations,convoluting fate-regulation analysis. We patterned hPSCs into engineered micro-environments and screened responses to 400 small-molecule kinase inhibitors,measuring yield and purity outputs of undifferentiated,neuroectoderm,mesendoderm,and extra-embryonic populations. Enrichment analysis revealed mammalian target of rapamycin (mTOR) inhibition as a strong inducer of mesendoderm. Dose responses of mTOR inhibitors such as rapamycin synergized with Bone Morphogenetic protein 4 (BMP4) and activin A to enhance the yield and purity of BRACHYURY-expressing cells. Mechanistically,small interfering RNA knockdown of RAPTOR,a component of mTOR complex 1,phenocopied the mesendoderm-enhancing effects of rapamycin. Functional analysis during mesoderm and endoderm differentiation revealed that mTOR inhibition increased the output of hemogenic endothelial cells 3-fold,with a concomitant enhancement of blood colony-forming cells. These data demonstrate the power of our multi-lineage screening approach and identify mTOR signaling as a node in hPSC differentiation to mesendoderm and its derivatives. View Publication

Declined production of collagen by fibroblasts is one of the major causes of aging appearance. However,only few of compounds found in cosmetic products are able to directly increase collagen synthesis. A novel small heterocyclic compound called kartogenin (KGN) was found to stimulate collagen synthesis of mesenchymal stem cells (MSCs). So,we hypothesized and tested that if KGN could be applied to stimulate the collagen synthesis of fibroblasts. Human dermal fibroblasts in vitro were treated with various concentrations of KGN,with dimethyl sulfoxide (DMSO) serving as the negative control. Real-time reverse-transcription polymerase chain reaction,Western blot,and immunofluorescence analyses were performed to examine the expression of collagen and transforming growth factor beta (TGF-β) signaling pathway. The production of collagen was also tested in vivo by Masson's trichrome stain and immunohistochemistry in the dermis of mice administrated with KGN. Results showed that without obvious influence on fibroblasts' apoptosis and viability,KGN stimulated type-I collagen synthesis of fibroblasts at the mRNA and protein levels in a time-dependent manner,but KGN did not induce expression of α-skeletal muscle actin (α-sma) or matrix metallopeptidase1 (MMP1),MMP9 in vitro. Smad4/smad5 of the TGF-β signaling pathway was activated by KGN while MAPK signaling pathway remained unchanged. KGN also increased type-I collagen synthesis in the dermis of BALB/C mice. Our results indicated that KGN promoted the type-I collagen synthesis of dermal fibroblasts in vitro and in the dermis of mice through activation of the smad4/smad5 pathway. This molecule could be used in wound healing,tissue engineering of fibroblasts,or aesthetic and reconstructive procedures. View Publication

Dysregulated chronic inflammation plays a crucial role in the pathophysiology of atherosclerosis and may be a result of impaired resolution. Thus,restoring levels of specialized pro-resolving mediators (SPMs) to promote the resolution of inflammation has been proposed as a therapeutic strategy for patients with atherosclerosis,in addition to standard clinical care. Herein,we evaluated the effects of the SPM lipids,lipoxin A4 (LXA4 ) and lipoxin B4 (LXB4 ),on neutrophils isolated from patients with atherosclerosis compared with healthy controls. Patients displayed altered endogenous SPM production,and we demonstrated that lipoxin treatment in whole blood from atherosclerosis patients attenuates neutrophil oxidative burst,a key contributor to atherosclerotic development. We found the opposite effect in neutrophils from healthy controls,indicating a potential mechanism whereby lipoxins aid the endogenous neutrophil function in health but reduce its excessive activation in disease. We also demonstrated that lipoxins attenuated upregulation of the high-affinity conformation of the CD11b/CD18 integrin,which plays a central role in clot activation and atherosclerosis. Finally,LXB4 enhanced lymphatic transmigration of human neutrophils isolated from patients with atherosclerosis. This finding is noteworthy,as impaired lymphatic function is now recognized as an important contributor to atherosclerosis. Although both lipoxins modulated neutrophil function,LXB4 displayed more potent effects than LXA4 in humans. This study highlights the therapeutic potential of lipoxins in atherosclerotic disease and demonstrates that the effect of these SPMs may be specifically tailored to the need of the individual. View Publication

SummaryCytoplasmic mislocalization and aggregation of the RNA-binding protein TDP-43 is a pathological hallmark of the motor neuron (MN) disease amyotrophic lateral sclerosis (ALS). Furthermore,while mutations in TARDBP (encoding TDP-43) have been associated with ALS,the pathogenic consequences of these mutations remain poorly understood. Using CRISPR-Cas9,we engineered two homozygous knock-in induced pluripotent stem cell lines carrying mutations in TARDBP encoding TDP-43A382T and TDP-43G348C,two common yet understudied ALS TDP-43 variants. Motor neurons (MNs) differentiated from knock-in iPSCs had normal viability and displayed no significant changes in TDP-43 subcellular localization,phosphorylation,solubility,or aggregation compared with isogenic control MNs. However,our results highlight synaptic impairments in both TDP-43A382T and TDP-43G348C MN cultures,as reflected in synapse abnormalities and alterations in spontaneous neuronal activity. Collectively,our findings suggest that MN dysfunction may precede the occurrence of TDP-43 pathology and neurodegeneration in ALS and further implicate synaptic and excitability defects in the pathobiology of this disease. Graphical abstract Highlights•Mutant MNs maintain viability but are more vulnerable to cellular stress•Mutant MNs do not show TDP-43 pathology•TDP-43 variants lead to a progressive decline in spontaneous neuronal activity•Functional impairments are accompanied by abnormal synaptic marker expression Molecular neuroscience; Cellular neuroscience View Publication

Interactions between adipose tissue,liver and immune system are at the center of metabolic dysfunction-associated steatotic liver disease and type 2 diabetes. To address the need for an accurate in vitro model,we establish an interconnected microphysiological system (MPS) containing white adipocytes,hepatocytes and proinflammatory macrophages derived from isogenic human induced pluripotent stem cells. Using this MPS,we find that increasing the adipocyte-to-hepatocyte ratio moderately affects hepatocyte function,whereas macrophage-induced adipocyte inflammation causes lipid accumulation in hepatocytes and MPS-wide insulin resistance,corresponding to initiation of metabolic dysfunction-associated steatotic liver disease. We also use our MPS to identify and characterize pharmacological intervention strategies for hepatic steatosis and systemic insulin resistance and find that the glucagon-like peptide-1 receptor agonist semaglutide improves hepatocyte function by acting specifically on adipocytes. These results establish our MPS modeling the adipose tissue-liver axis as an alternative to animal models for mechanistic studies or drug discovery in metabolic diseases. In vitro modelling of the adipose tissue-liver axis can advance understanding and therapy of metabolic disease,including by distinguishing effects of obesity and inflammation. Here,authors develop such a system based on isogenic human iPSCs and interconnected microphysiological devices. View Publication

SummaryHuman cerebral organoids derived from induced pluripotent stem cells can recapture early developmental processes and reveal changes involving neurodevelopmental disorders. Mutations in the X-linked methyl-CpG binding protein 2 (MECP2) gene are associated with Rett syndrome,and disease severity varies depending on the location and type of mutation. Here,we focused on neuronal activity in Rett syndrome patient-derived organoids,analyzing two types of MeCP2 mutations – a missense mutation (R306C) and a truncating mutation (V247X) - using calcium imaging with three-photon microscopy. Compared to isogenic controls,we found abnormal neuronal activity in Rett organoids and altered network function based on graph theoretic analyses,with V247X mutations impacting functional responses and connectivity more severely than R306C mutations. These changes paralleled EEG data obtained from patients with comparable mutations. Labeling DLX promoter-driven inhibitory neurons demonstrated differences in activity and functional connectivity of inhibitory and excitatory neurons in the two types of mutation. Transcriptomic analyses revealed HDAC2-associated impairment in R306C organoids and decreased GABAA receptor expression in excitatory neurons in V247X organoids. These findings demonstrate mutation-specific mechanisms of vulnerability in Rett syndrome and suggest targeted strategies for their treatment. View Publication

To date,the effects of endurance exercise training on lymphocyte physiology at the kinome level are largely unknown. Therefore,the present study used a highly sensitive peptide-based kinase activity profiling approach to investigate if the basal activity of tyrosine (Tyr) and serine/threonine (Ser/Thr) kinases of human lymphocytes is affected by the aerobic endurance training status. Results revealed that the activity of various tyrosine kinases of the FGFR family and ZAP70 was increased,whereas the activity of multiple Ser/Thr kinases such as IKK$\alpha$,CaMK4,PKA$\alpha$,PKC$\alpha$+$\delta$ (among others) was decreased in lymphocytes of endurance trained athletes (ET). Moreover,functional associations between several differentially regulated kinases in ET-derived lymphocytes were demonstrated by phylogenetic mapping and network analysis. Especially,Ser/Thr kinases of the AGC-kinase (protein kinase A,G,and C) family represent exercise-sensitive key components within the lymphocytes kinase network that may mediate the long-term effects of endurance training. Furthermore,KEGG (Kyoto Encyclopedia of Genes and Genomes) and Reactome pathway analysis indicate that Ras as well as intracellular signaling by second messengers were found to be enriched in the ET individuals. Overall,our data suggest that endurance exercise training improves the adaptive immune competence by modulating the activity of multiple protein kinases in human lymphocytes. View Publication

While readily achieved in cell lines,the application of CRISPR-Cas9 gene editing in human-derived organoids suffers from limited efficacy and complex protocols. Here,we describe a multi-guide RNA CRISPR-Cas9 gene-editing protocol which efficiently achieves complete gene knockout in adult human colonic organoids. This protocol also describes crucial steps including how to harvest patient tissue to maximize gene-editing efficacy and a technique to validate gene knockout following editing with immunofluorescent staining of the organoids against the target protein. View Publication

Neural cells in the adult human central nervous system (CNS) display extensive transcriptional heterogeneity. How different layers of epigenetic regulation underpin this heterogeneity is poorly understood. Here we profile,at the single-nuclei epigenomic level,distinct regions of the adult human CNS,for chromatin accessibility and simultaneously for the histone modifications H3K27me3 and H3K27ac. We unveil a putative SOX10 enhancer and primed chromatin signatures at HOX loci in spinal-cord-derived human oligodendroglia (OLG) and astrocytes,but not microglia. These signatures in adult OLG were reminiscent of developmental profiles but were decoupled from robust gene expression. Moreover,using high-resolution Micro-C,we show that induced pluripotent stem-cell-derived human OLGs exhibit a HOX chromatin architecture compatible with the primed chromatin in adult OLGs,bearing a strong resemblance not only to OLG developmental architecture but also to high-grade pontine gliomas. Thus,epigenetic memory from developmental states in adult OLG not only enables them to promptly transcribe Hox family genes during regeneration but also makes them susceptible to gliomagenesis. Single-nucleus epigenomic maps of the adult human brain and spinal cord reveal that adult oligodendroglia retain developmental chromatin patterns,suggesting a molecular memory that may shape repair processes and cancer vulnerability. View Publication

B cell dysregulation in aging is thought to mostly occur in conventional B2 cells without affecting innate B1 cells. Elderly humans and mice also accumulate 4-1BBL(+)MHC class-I(Hi)CD86(Hi)B cells of unknown origin. In this article,we report that these cells,termed 4BL cells,are activated murine and possibly human B1a cells. The activation is mediated by aging human monocytes and murine peritoneal macrophages. They induce expression and activation of 4-1BBL and IFN-γR1 on B1a cells to subsequently upregulate membrane TNF-α and CD86. As a result,activated B1a/4BL cells induce expression of granzyme B in CD8(+)T cells by targeting TNFR2 via membrane TNF-α and providing costimulation with CD86. Thus,for the first time,to our knowledge,these results indicate that aging affects the function of B1a cells. Upon aging,these cells lose their tumor-supporting activity and become inducers of potentially antitumor and autoimmune CD8(+)T cells. View Publication