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We report here the cloning,expression,and characterization of human PDE11A1,a member of a distinct cyclic nucleotide phosphodiesterase (PDE) family. PDE11A exhibits textless/=50% amino acid identity with the catalytic domains of all other PDEs,being most similar to PDE5,and has distinct biochemical properties. The human PDE11A1 cDNA isolated contains a complete open reading frame encoding a 490-amino acid enzyme with a predicted molecular mass of 55,786 Da. At the N terminus PDE11A1 has a single GAF domain homologous to that found in other signaling molecules,including PDE2,PDE5,PDE6,and PDE10,which constitutes a potential allosteric binding site for cGMP or another small ligand. Tissue distribution studies indicate that PDE11A mRNA occurs at highest levels in skeletal muscle,prostate,kidney,liver,pituitary,and salivary glands and testis. PDE11A is expressed as at least three major transcripts of approximately 10.5,approximately 8.5,and approximately 6.0 kb,thus suggesting the existence of multiple subtypes. This possibility is further supported by the detection of three distinct proteins of approximately 78,approximately 65,and approximately 56 kDa by Western blotting of human tissues for PDE11A isoforms. Recombinant human PDE11A1 hydrolyzes both cGMP and cAMP with K(m) values of 0.52 microM and 1.04 microM,respectively,and similar V(max) values. Therefore,PDE11A represents a dual-substrate PDE that may regulate both cGMP and cAMP under physiological conditions. PDE11A is sensitive to the nonselective PDE inhibitor 3-isobutyl-1-methylxanthine (IBMX) as well as zaprinast and dipyridamole,inhibitors that are generally considered relatively specific for the cGMP-selective PDEs,with IC(50) values of 49.8 microM,12.0 microM,and 0.37 microM,respectively. View Publication

1. Polymorphonuclear leukocytes (PMN) may contribute to the pathogenesis of acute coronary heart disease (CHD). 2. Epidemiological and laboratory evidence suggests that red wine,by virtue of its polyphenolic constituents,may be more effective than other alcoholic beverages in reducing the risk of CHD mortality. 3 The aim of the present study was to investigate the effects of trans-resveratrol (3,4',5-trihydroxy-trans-stilbene),a polyphenol present in most red wines,on functional and biochemical responses of PMN,upon in vitro activation. 4. trans-Resveratrol exerted a strong inhibitory effect on reactive oxygen species produced by PMN stimulated with 1 microM formyl methionyl leucyl phenylalamine (fMLP) (IC50 1.3+/-0.13 microM,mean+/-s.e.mean),as evaluated by luminol-amplified chemiluminescence. 5. trans-Resveratrol prevented the release of elastase and beta-glucuronidase by PMN stimulated with the receptor agonists fMLP (1 microM,IC50 18.4+/-1.8 and 31+/-1.8 microM),and C5a (0.1 microM,IC50 41.6+/-3.5 and 42+/-8.3 microM),and also inhibited elastase and beta-glucuronidase secretion (IC50 37.7+/-7 and 25.4+/-2.2 microM) and production of 5-lipoxygenase metabolites leukotriene B4 (LTB4),6-trans-LTB4 and 12-trans-epi-LTB4 (IC50 48+/-7 microM) by PMN stimulated with the calcium ionophore A23187 (5 microM). 6. trans-Resveratrol significantly reduced the expression and activation of the beta2 integrin MAC-1 on PMN surface following stimulation,as revealed by FACS analysis of the binding of an anti-MAC-1 monoclonal antibody (MoAb) and of the CBRM1/5 MoAb,recognizing an activation-dependent epitope on MAC-1. Consistently,PMN homotypic aggregation and formation of mixed cell-conjugates between PMN and thrombin-stimulated fixed platelets in a dynamic system were also prevented by transresveratrol. 7. These results,indicating that trans-resveratrol interferes with the release of inflammatory mediators by activated PMN and down-regulates adhesion-dependent thrombogenic PMN functions,may provide some biological plausibility to the protective effect of red wine consumption against CHD. View Publication

Mitochondrial diseases are genetically heterogeneous and present a broad clinical spectrum among patients; in most cases,genetic determinants of mitochondrial diseases are heteroplasmic mitochondrial DNA (mtDNA) mutations. However,it is uncertain whether and how heteroplasmic mtDNA mutations affect particular cellular fate-determination processes,which are closely associated with the cell-type-specific pathophysiology of mitochondrial diseases. In this study,we established two isogenic induced pluripotent stem cell (iPSC) lines each carrying different proportions of a heteroplasmic m.3243A>G mutation from the same patient; one exhibited apparently normal and the other showed most likely impaired mitochondrial respiratory function. Low proportions of m.3243A>G exhibited no apparent molecular pathogenic influence on directed differentiation into neurons and cardiomyocytes,whereas high proportions of m.3243A>G showed both induced neuronal cell death and inhibited cardiac lineage commitment. Such neuronal and cardiac maturation defects were also confirmed using another patient-derived iPSC line carrying quite high proportion of m.3243A>G. In conclusion,mitochondrial respiratory dysfunction strongly inhibits maturation and survival of iPSC-derived neurons and cardiomyocytes; our presenting data also suggest that appropriate mitochondrial maturation actually contributes to cellular fate-determination processes during development. View Publication

Tissue-resident macrophages,such as microglia,Kupffer cells,and Langerhans cells,derive from Myb-independent yolk sac (YS) progenitors generated before the emergence of hematopoietic stem cells (HSCs). Myb-independent YS-derived resident macrophages self-renew locally,independently of circulating monocytes and HSCs. In contrast,adult blood monocytes,as well as infiltrating,gut,and dermal macrophages,derive from Myb-dependent HSCs. These findings are derived from the mouse,using gene knockouts and lineage tracing,but their applicability to human development has not been formally demonstrated. Here,we use human induced pluripotent stem cells (iPSCs) as a tool to model human hematopoietic development. By using a CRISPR-Cas9 knockout strategy,we show that human iPSC-derived monocytes/macrophages develop in an MYB-independent,RUNX1-,and SPI1 (PU.1)-dependent fashion. This result makes human iPSC-derived macrophages developmentally related to and a good model for MYB-independent tissue-resident macrophages,such as alveolar and kidney macrophages,microglia,Kupffer cells,and Langerhans cells. View Publication

Although clonal studies of lineage potential have been extensively applied to organ specific stem and progenitor cells,much less is known about the clonal origins of lineages formed from the germ layers in early embryogenesis. We applied lentiviral tagging followed by vector integration site analysis (VISA) with high-throughput sequencing to investigate the ontogeny of the hematopoietic,endothelial and mesenchymal lineages as they emerge from human embryonic mesoderm. In contrast to studies that have used VISA to track differentiation of self-renewing stem cell clones that amplify significantly over time,we focused on a population of progenitor clones with limited self-renewal capability. Our analyses uncovered the critical influence of sampling on the interpretation of lentiviral tag sharing,particularly among complex populations with minimal clonal duplication. By applying a quantitative framework to estimate the degree of undersampling we revealed the existence of tripotent mesodermal progenitors derived from pluripotent stem cells,and the subsequent bifurcation of their differentiation into bipotent endothelial/hematopoietic or endothelial/mesenchymal progenitors. This article is protected by copyright. All rights reserved. View Publication

Immune tolerance is executed partly by Foxp3(+)regulatory T (Treg) cells,which suppress autoreactive T cells. In autoimmune type 1 diabetes (T1D) impaired tolerance promotes destruction of insulin-producing β-cells. The development of autoantigen-specific vaccination strategies for Foxp3(+)Treg-induction and prevention of islet autoimmunity in patients is still in its infancy. Here,using human haematopoietic stem cell-engrafted NSG-HLA-DQ8 transgenic mice,we provide direct evidence for human autoantigen-specific Foxp3(+)Treg-induction in vivo. We identify HLA-DQ8-restricted insulin-specific CD4(+)T cells and demonstrate efficient human insulin-specific Foxp3(+)Treg-induction upon subimmunogenic vaccination with strong agonistic insulin mimetopes in vivo. Induced human Tregs are stable,show increased expression of Treg signature genes such as Foxp3,CTLA4,IL-2Rα and TIGIT and can efficiently suppress effector T cells. Such Foxp3(+)Treg-induction does not trigger any effector T cells. These T1D vaccine candidates could therefore represent an expedient improvement in the challenge to induce human Foxp3(+)Tregs and to develop novel precision medicines for prevention of islet autoimmunity in children at risk of T1D. View Publication

Background: Huntington's disease (HD) is an incurable hereditary neurodegenerative disorder,which manifests itself as a loss of GABAergic medium spiny (GABA MS) neurons in the striatum and caused by an expansion of the CAG repeat in exon 1 of the huntingtin gene. There is no cure for HD,existing pharmaceutical can only relieve its symptoms. Results: Here,induced pluripotent stem cells were established from patients with low CAG repeat expansion in the huntingtin gene,and were then efficiently differentiated into GABA MS-like neurons (GMSLNs) under defined culture conditions. The generated HD GMSLNs recapitulated disease pathology in vitro,as evidenced by mutant huntingtin protein aggregation,increased number of lysosomes/autophagosomes,nuclear indentations,and enhanced neuronal death during cell aging. Moreover,store-operated channel (SOC) currents were detected in the differentiated neurons,and enhanced calcium entry was reproducibly demonstrated in all HD GMSLNs genotypes. Additionally,the quinazoline derivative,EVP4593,reduced the number of lysosomes/autophagosomes and SOC currents in HD GMSLNs and exerted neuroprotective effects during cell aging. Conclusions: Our data is the first to demonstrate the direct link of nuclear morphology and SOC calcium deregulation to mutant huntingtin protein expression in iPSCs-derived neurons with disease-mimetic hallmarks,providing a valuable tool for identification of candidate anti-HD drugs. Our experiments demonstrated that EVP4593 may be a promising anti-HD drug. [ABSTRACT FROM AUTHOR] View Publication

Normalization of human RNA-seq experiments employing chimpanzee RNA as a spike-in standard is reported. Human and chimpanzee RNAs exhibit single nucleotide variations (SNVs) in average 210-bp intervals. Spike-in chimpanzee RNA would behave the same as the human counterparts during the whole NGS procedures owing to the high sequence similarity. After discrimination of species origins of the NGS reads based on SNVs,the chimpanzee reads were used to read-by-read normalize biases and variations of human reads. By this approach,as many as 10,119 transcripts were simultaneously normalized for the entire NGS procedures leading to accurate and reproducible quantification of differential gene expression. In addition,incomparable data sets from different in-process degradations or from different library preparation methods were made well comparable by the normalization. Based on these results,we expect that the normalization approaches using near neighbor genomes as internal standards could be employed as a standard protocol,which will improve both accuracy and comparability of NGS results across different sample batches,laboratories and NGS platforms. View Publication

Applications of human induced pluripotent stem cell derived-cardiac myocytes (hiPSC-CMs) would be strengthened by the ability to generate specific cardiac myocyte (CM) lineages. However,purification of lineage-specific hiPSC-CMs is limited by the lack of cell marking techniques. Here,we have developed an iPSC-CM marking system using recombinant adenoviral reporter constructs with atrial- or ventricular-specific myosin light chain-2 (MLC-2) promoters. MLC-2a and MLC-2v selected hiPSC-CMs were purified by fluorescence-activated cell sorting and their biochemical and electrophysiological phenotypes analyzed. We demonstrate that the phenotype of both populations remained stable in culture and they expressed the expected sarcomeric proteins,gap junction proteins and chamber-specific transcription factors. Compared to MLC-2a cells,MLC-2v selected CMs had larger action potential amplitudes and durations. In addition,by immunofluorescence,we showed that MLC-2 isoform expression can be used to enrich hiPSC-CM consistent with early atrial and ventricular myocyte lineages. However,only the ventricular myosin light chain-2 promoter was able to purify a highly homogeneous population of iPSC-CMs. Using this approach,it is now possible to develop ventricular-specific disease models using iPSC-CMs while atrial-specific iPSC-CM cultures may require additional chamber-specific markers. ?? 2013 Elsevier B.V. View Publication

High-dose,posttransplantation cyclophosphamide (PTCy) is an effective strategy for preventing graft-versus-host disease (GVHD) after allogeneic blood or marrow transplantation (alloBMT). However,the mechanisms by which PTCy modulates alloimmune responses are not well understood. We studied early T cell reconstitution in patients undergoing alloBMT with PTCy and the effects of mafosfamide,a cyclophosphamide (Cy) analog,on CD4(+) T cells in allogeneic mixed lymphocyte reactions (MLRs) in vitro. Patients exhibited reductions in naïve,potentially alloreactive conventional CD4(+) T cells with relative preservation of memory CD4(+)Foxp3(+) T cells. In particular,CD4(+)CD45RA(-)Foxp3(+hi) effector regulatory T cells (Tregs) recovered rapidly after alloBMT and,unexpectedly,were present at higher levels in patients with GVHD. CD4(+)Foxp3(+) T cells from patients and from allogeneic MLRs expressed relatively high levels of aldehyde dehydrogenase (ALDH),the major in vivo mechanism of Cy resistance. Treatment of MLR cultures with the ALDH inhibitor diethylaminobenzaldehyde reduced the activation and proliferation of CD4(+) T cells and sensitized Tregs to mafosfamide. Finally,removing Tregs from peripheral blood lymphocyte grafts obviated PTCy's GVHD-protective effect in a xenogeneic transplant model. Together,these findings suggest that Treg resistance to Cy through expression of ALDH may contribute to the clinical activity of PTCy in preventing GVHD. View Publication

PURPOSE: Retinal pigmented epithelium derived from human induced pluripotent stem (iPS) cells (iPS-RPE) may be a source of cells for transplantation. For this reason,it is essential to determine the functional competence of iPS-RPE. One key role of the RPE is uptake and processing of retinoids via the visual cycle. The purpose of this study is to investigate the expression of visual cycle proteins and the functional ability of the visual cycle in iPS-RPE.$$n$$nMETHODS: iPS-RPE was derived from human iPS cells. Immunocytochemistry,RT-PCR,and Western blot analysis were used to detect expression of RPE genes lecithin-retinol acyl transferase (LRAT),RPE65,cellular retinaldehyde-binding protein (CRALBP),and pigment epithelium-derived factor (PEDF). All-trans retinol was delivered to cultured cells or whole cell homogenate to assess the ability of the iPS-RPE to process retinoids.$$n$$nRESULTS: Cultured iPS-RPE expresses visual cycle genes LRAT,CRALBP,and RPE65. After incubation with all-trans retinol,iPS-RPE synthesized up to 2942 ± 551 pmol/mg protein all-trans retinyl esters. Inhibition of LRAT with N-ethylmaleimide (NEM) prevented retinyl ester synthesis. Significantly,after incubation with all-trans retinol,iPS-RPE released 188 ± 88 pmol/mg protein 11-cis retinaldehyde into the culture media.$$n$$nCONCLUSIONS: iPS-RPE develops classic RPE characteristics and maintains expression of visual cycle proteins. The results of this study confirm that iPS-RPE possesses the machinery to process retinoids for support of visual pigment regeneration. Inhibition of all-trans retinyl ester accumulation by NEM confirms LRAT is active in iPS-RPE. Finally,the detection of 11-cis retinaldehyde in the culture medium demonstrates the cells' ability to process retinoids through the visual cycle. This study demonstrates expression of key visual cycle machinery and complete visual cycle activity in iPS-RPE. View Publication