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We investigate the effects of myocardial transplantation of human induced pluripotent stem cell (iPSC)-derived progenitors and cardiomyocytes into acutely infarcted myocardium in severe combined immune deficiency mice. A total of 2 × 10(5) progenitors,cardiomyocytes or cell-free saline were injected into peri-infarcted anterior free wall. Sham-operated animals received no injection. Myocardial function was assessed at 2-week and 4-week post-infarction by using echocardiography and pressure-volume catheterization. Early myocardial remodelling was observed at 2-week with echocardiography derived stroke volume (SV) in saline (20.45 ± 7.36 $\$,P textless 0.05) and cardiomyocyte (19.52 ± 3.97 $\$,P textless 0.05) groups,but not in progenitor group (25.65 ± 3.61 $\$),significantly deteriorated as compared to sham control group (28.41 ± 4.41 $\$). Consistently,pressure-volume haemodynamic measurements showed worsening chamber dilation in saline (EDV: 23.24 ± 5.01 $\$,P textless 0.05; ESV: 17.08 ± 5.82 $\$,P textless 0.05) and cardiomyocyte (EDV: 26.45 ± 5.69 $\$,P textless 0.05; ESV: 18.03 ± 6.58 $\$,P textless 0.05) groups by 4-week post-infarction as compared to control (EDV: 15.26 ± 2.96 $\$; ESV: 8.41 ± 2.94 $\$). In contrast,cardiac progenitors (EDV: 20.09 ± 7.76 $\$; ESV: 13.98 ± 6.74 $\$) persistently protected chamber geometry against negative cardiac remodelling. Similarly,as compared to sham control (54.64 ± 11.37%),LV ejection fraction was preserved in progenitor group from 2-(38.68 ± 7.34%) to 4-week (39.56 ± 13.26%) while cardiomyocyte (36.52 ± 11.39%,P textless 0.05) and saline (35.34 ± 11.86%,P textless 0.05) groups deteriorated early at 2-week. Improvements of myocardial function in the progenitor group corresponded to increased vascularization (16.12 ± 1.49/mm(2) to 25.48 ± 2.08/mm(2) myocardial tissue,P textless 0.05) and coincided with augmented networking of cardiac telocytes in the interstitial space of infarcted zone. View Publication

Long intergenic noncoding RNAs (lincRNAs) are derived from thousands of loci in mammalian genomes and are frequently enriched in transposable elements (TEs). Although families of TE-derived lincRNAs have recently been implicated in the regulation of pluripotency,little is known of the specific functions of individual family members. Here we characterize three new individual TE-derived human lincRNAs,human pluripotency-associated transcripts 2,3 and 5 (HPAT2,HPAT3 and HPAT5). Loss-of-function experiments indicate that HPAT2,HPAT3 and HPAT5 function in preimplantation embryo development to modulate the acquisition of pluripotency and the formation of the inner cell mass. CRISPR-mediated disruption of the genes for these lincRNAs in pluripotent stem cells,followed by whole-transcriptome analysis,identifies HPAT5 as a key component of the pluripotency network. Protein binding and reporter-based assays further demonstrate that HPAT5 interacts with the let-7 microRNA family. Our results indicate that unique individual members of large primate-specific lincRNA families modulate gene expression during development and differentiation to reinforce cell fate. View Publication

X-ALD is an inherited neurodegenerative disorder where mutations in the ABCD1 gene result in clinically diverse phenotypes: the fatal disorder of cerebral childhood ALD (cALD) or a milder disorder of adrenomyeloneuropathy (AMN). The various models used to study the pathobiology of X-ALD disease lack the appropriate presentation for different phenotypes of cALD vs AMN. This study demonstrates that induced pluripotent stem cells (IPSC) derived brain cells astrocytes (Ast),neurons and oligodendrocytes (OLs) express morphological and functional activities of the respective brain cell types. The excessive accumulation of saturated VLCFA,a hallmark" of X-ALD� View Publication

Hyaluronic acid (HA) has been cross-linked to form hydrogel for potential applications in the self-renewal and differentiation of human pluripotent stem cells (hPSCs) for years. However,HA hydrogel with improved residence time and mechanical integrity that allows the survival of hPSCs under defined conditions is still much needed for clinical applications. In this study,HA was modified with methacrylate functional groups (MeHA) and cross-linked by photo-crosslinking method. After subsequent conjugation with adhesive peptide,these MeHA surfaces demonstrated performance in facilitating human induced pluripotent stem cells (hiPSCs) proliferation,and good pluripotency maintenance of hiPSCs under defined conditions. Moreover,MeHA films on glass-slides exhibited long residence time and mechanical stability throughout hiPSC culture. Our photo-crosslinkable MeHA possesses great value in accelerating the application of HA hydrogel in hiPSCs proliferation and differentiation with the conjugation of adhesive peptides. View Publication

The prevalence and specificity of unique fusion oncogenes are high in a number of soft tissue sarcomas (STSs). The close relationship between fusion genes and clinicopathological features suggests that a correlation may exist between the function of fusion proteins and cellular context of the cell-of-origin of each tumor. However,most STSs are origin-unknown tumors and this issue has not yet been investigated in detail. In the present study,we examined the effects of the cellular context on the function of the synovial sarcoma (SS)-specific fusion protein,SS18-SSX,using human pluripotent stem cells (hPSCs) containing the drug-inducible SS18-SSX gene. We selected the neural crest cell (NCC) lineage for the first trial of this system,induced SS18-SSX at various differentiation stages from PSCs to NCC-derived mesenchymal stromal cells (MSCs),and compared its biological effects on each cell type. We found that the expression of FZD10,identified as an SS-specific gene,was induced by SS18-SSX at the PSC and NCC stages,but not at the MSC stage. This stage-specific induction of FZD10 correlated with stage-specific changes in histone marks associated with the FZD10 locus and also with the loss of the BAF47 protein,a member of the SWI/SNF chromatin-remodeling complex. Furthermore,the global gene expression profile of hPSC-derived NCCs was the closest to that of SS cell lines after the induction of SS18-SSX. These results clearly demonstrated that the cellular context is an important factor in the function of SS18-SSX as an epigenetic modifier. View Publication

Human pluripotent stem cells (hPSCs) represent very promising resources for cell-based regenerative medicine. It is essential to determine the biological implications of some fundamental physiological processes (such as glycogen metabolism) in these stem cells. In this report,we employ electron,immunofluorescence microscopy,and biochemical methods to study glycogen synthesis in hPSCs. Our results indicate that there is a high level of glycogen synthesis (0.28 to 0.62 $$g/$$g proteins) in undifferentiated human embryonic stem cells (hESCs) compared with the glycogen levels (0 to 0.25 $$g/$$g proteins) reported in human cancer cell lines. Moreover,we found that glycogen synthesis was regulated by bone morphogenetic protein 4 (BMP-4) and the glycogen synthase kinase 3 (GSK-3) pathway. Our observation of glycogen bodies and sustained expression of the pluripotent factor Oct-4 mediated by the potent GSK-3 inhibitor CHIR-99021 reveals an altered pluripotent state in hPSC culture. We further confirmed glycogen variations under different naïve pluripotent cell growth conditions based on the addition of the GSK-3 inhibitor BIO. Our data suggest that primed hPSCs treated with naïve growth conditions acquire altered pluripotent states,similar to those naïve-like hPSCs,with increased glycogen synthesis. Furthermore,we found that suppression of phosphorylated glycogen synthase was an underlying mechanism responsible for altered glycogen synthesis. Thus,our novel findings regarding the dynamic changes in glycogen metabolism provide new markers to assess the energetic and various pluripotent states in hPSCs. The components of glycogen metabolic pathways offer new assays to delineate previously unrecognized properties of hPSCs under different growth conditions. View Publication

The translation of laboratory processes into scaled production systems suitable for manufacture is a significant challenge for cell based therapies; in particular there is a lack of analytical methods that are informative and efficient for process control. Here the potential of image analysis as one part of the solution to this issue is explored,using pluripotent stem cell colonies as a valuable and challenging exemplar. The Cell-IQ live cell imaging platform was used to build image libraries of morphological culture attributes such as colony edge� View Publication

Fibroblasts from patients with Type I bipolar disorder (BPD) and their unaffected siblings were obtained from an Old Order Amish pedigree with a high incidence of BPD and reprogrammed to induced pluripotent stem cells (iPSCs). Established iPSCs were subsequently differentiated into neuroprogenitors (NPs) and then to neurons. Transcriptomic microarray analysis was conducted on RNA samples from iPSCs,NPs and neurons matured in culture for either 2 weeks (termed early neurons,E) or 4 weeks (termed late neurons,L). Global RNA profiling indicated that BPD and control iPSCs differentiated into NPs and neurons at a similar rate,enabling studies of differentially expressed genes in neurons from controls and BPD cases. Significant disease-associated differences in gene expression were observed only in L neurons. Specifically,328 genes were differentially expressed between BPD and control L neurons including GAD1,glutamate decarboxylase 1 (2.5 fold) and SCN4B,the voltage gated type IV sodium channel beta subunit (-14.6 fold). Quantitative RT-PCR confirmed the up-regulation of GAD1 in BPD compared to control L neurons. Gene Ontology,GeneGo and Ingenuity Pathway Analysis of differentially regulated genes in L neurons suggest that alterations in RNA biosynthesis and metabolism,protein trafficking as well as receptor signaling pathways may play an important role in the pathophysiology of BPD. View Publication

A microfluidic human pluripotent stem cell (hPSC) array has been developed for robust and reproducible hPSC culture methods to assess chemically defined serum- and feeder-free culture conditions. This microfluidic platform,combined with image cytometry,enables the systematic analysis of multiple simultaneously detected marker expression in individual cells,for screening of various chemically defined media across hPSC lines,and the study of phenotypic responses. View Publication

The ability to manipulate transcription in human pluripotent stem cells (hPSCs) is fundamental for the discovery of key genes and mechanisms governing cellular state and differentiation. Recently developed CRISPR-effector systems provide a systematic approach to rapidly test gene function in mammalian cells,including hPSCs. In this review,we discuss recent advances in CRISPR-effector technologies that have been employed to control transcription through gene activation,gene repression,and epigenome engineering. We describe an application of CRISPR-effector mediated transcriptional regulation in hPSCs by targeting a synthetic promoter driving a GFP transgene,demonstrating the ease and effectiveness of CRISPR-effector mediated transcriptional regulation in hPSCs. View Publication

Bipolar disorder is a complex neuropsychiatric disorder that is characterized by intermittent episodes of mania and depression; without treatment,15% of patients commit suicide. Hence,it has been ranked by the World Health Organization as a top disorder of morbidity and lost productivity. Previous neuropathological studies have revealed a series of alterations in the brains of patients with bipolar disorder or animal models,such as reduced glial cell number in the prefrontal cortex of patients,upregulated activities of the protein kinase A and C pathways and changes in neurotransmission. However,the roles and causation of these changes in bipolar disorder have been too complex to exactly determine the pathology of the disease. Furthermore,although some patients show remarkable improvement with lithium treatment for yet unknown reasons,others are refractory to lithium treatment. Therefore,developing an accurate and powerful biological model for bipolar disorder has been a challenge. The introduction of induced pluripotent stem-cell (iPSC) technology has provided a new approach. Here we have developed an iPSC model for human bipolar disorder and investigated the cellular phenotypes of hippocampal dentate gyrus-like neurons derived from iPSCs of patients with bipolar disorder. Guided by RNA sequencing expression profiling,we have detected mitochondrial abnormalities in young neurons from patients with bipolar disorder by using mitochondrial assays; in addition,using both patch-clamp recording and somatic Ca(2+) imaging,we have observed hyperactive action-potential firing. This hyperexcitability phenotype of young neurons in bipolar disorder was selectively reversed by lithium treatment only in neurons derived from patients who also responded to lithium treatment. Therefore,hyperexcitability is one early endophenotype of bipolar disorder,and our model of iPSCs in this disease might be useful in developing new therapies and drugs aimed at its clinical treatment. View Publication

The diverse progenitors that give rise to the human neocortex have been difficult to characterize because progenitors,particularly radial glia (RG),are rare and are defined by a combination of intracellular markers,position and morphology. To circumvent these problems,we developed Fixed and Recovered Intact Single-cell RNA (FRISCR),a method for profiling the transcriptomes of individual fixed,stained and sorted cells. Using FRISCR,we profiled primary human RG that constitute only 1% of the midgestation cortex and classified them as ventricular zone-enriched RG (vRG) that express ANXA1 and CRYAB,and outer subventricular zone-localized RG (oRG) that express HOPX. Our study identified vRG and oRG markers and molecular profiles,an essential step for understanding human neocortical progenitor development. FRISCR allows targeted single-cell profiling of any tissues that lack live-cell markers. View Publication