Non-integrating Episomal Plasmids Research Articles

Generation and characterization of CSSi016-A (9938) human pluripotent stem cell line carrying two biallelic variants in MTMR5/SBF1 gene resulting in a case of severe CMT4B3

Charcot-Marie-Tooth type 4B3 (CMT4B3) is a rare subtype of hereditary neuropathy associated with variants in the MTMR5/SBF1 gene. Herein, we report the generation and characterization of a hiPSC line from a 12-year-old Italian girl with early onset severe polyneuropathy with motor and axonal involvement, harboring biallelic variants in the MTMR5/SBF1 gene. Fibroblasts were reprogrammed using non-integrating episomal plasmids, and iPSCs successfully passed the stemness and pluripotency tests. Patient-specific hiPSCs were produced to obtain a disease model for the study of this rare condition.

Generation and characterization of induced pluripotent stem cell (iPSC) lines of two asymptomatic individuals carrying a heterozygous exon 7 deletion in Parkin (PRKN) and two non-carriers from the same family

Mutations in the Parkin (PRKN) gene are the most frequent known cause of autosomal recessive early-onset Parkinson’s disease (PD). Heterozygous mutations might predispose to disease with a highly reduced penetrance. We generated iPSC lines from two individuals carrying a heterozygous deletion of exon 7 in the PRKN gene and two controls from the same family. PBMCs were reprogrammed using non-integrating episomal plasmids. The iPSC lines exhibit expression of pluripotency markers, the potential to differentiate into the three germ layers, and a stable karyotype. These lines will serve to study mechanisms of reduced penetrance in heterozygous PRKN mutation carriers.

Development and identification of a induced pluripotent stem cells line (SMBCi013-A) derived from urine cells of a patient with Wilson's disease

The human induced pluripotent stem cell (iPSC) line SMBCi013-A was derived from urine cells of a 29 year old male affected by Wilson’s disease. Two heterozygous mutations in the ATP7B gene were detected by whole exon sequencing (c.2303C > A and c.3334C > T). The reprogramming factors (OCT-4, SOX-2, KLF4, miR-302-367) were delivered using non-integrating episomal plasmids. The resulting iPSCs were pluripotent, have chromosomal stability, and the ability to differentiate into the three germ layers.

Generation of an induced pluripotent stem cell line (CSS012-A (7672)) carrying the p.G376D heterozygous mutation in the TARDBP protein

Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative condition with phenotypic and genetic heterogeneity. It is characterized by the selective vulnerability and the progressive loss of the neural population. Here, an induced pluripotent stem cell (iPSC) line was generated from dermal fibroblasts of an individual carrying the p.G376D mutation in the TDP-43 protein. Fibroblasts were reprogrammed using non-integrating episomal plasmids. There were no karyotype abnormalities, and iPSCs successfully differentiated into all three germ layers. This cell line may prove useful in the study of the pathogenic mechanisms that underpin ALS syndrome.

Generation of Human iPSCs by Episomal Reprogramming of Skin Fibroblasts and Peripheral Blood Mononuclear Cells.

Human-induced pluripotent stem cells (iPSCs) can be generated from patient-specific somatic cells by forced expression of the transcription factors OCT4, SOX2, KLF4, and c-MYC. Sustained expression of the transgenes during reprogramming is crucial for the successful derivation of iPSCs. Integrating retroviruses have been used to achieve the required prolonged expression; however, issues of undesirable transgene expression in the iPSC-derived cell types post reprogramming can occur. Alternative non-integrating approaches to reprogram somatic cells into pluripotency have been established. Here, we describe a detailed method for generating human iPSCs from fibroblasts and peripheral blood mononuclear cells (PBMCs) using the non-integrating episomal plasmids. The delivery of the episomal plasmids into the somatic cells is achieved using a nucleofection technique, and reprogramming is performed in chemically defined media. This process takes approximately 30days to establish the iPSC colonies. We also describe a method for growing iPSCs on vitronectin as well as procedures for the long-term expansion of iPSCs on human fibroblast feeder cells.

The generation of an induced pluripotent stem cell line (DCGi001-A) from an individual with FOXG1 syndrome carrying the c.460dupG (p.Glu154fs) variation in the FOXG1 gene.

FOXG1 syndrome is a neurodevelopmental disorder caused by mutations in the FOXG1 gene. Here, an induced pluripotent stem cell (iPSC) line was generated from human dermal fibroblasts of an individual with the c.490dupG (p.Glu154fs) mutation in the FOXG1 gene. Fibroblasts were reprogrammed using non-integrating episomal plasmids and pluripotency marker expression was confirmed by both immunocytochemistry and quantitative PCR in the resultant iPSC line. There were no karyotypic abnormalities and the cell line successfully differentiated into all three germ layers. This cell line may prove useful in the study of the pathogenic mechanisms that underpin FOXG1 syndrome.

Generation of eight human induced pluripotent stem cell lines from Parkinson's disease patients carrying familial mutations.

We generated eight induced pluripotent stem cell (iPSC) lines from Parkinson's disease (PD) patients with different familial mutations using non-integrating episomal plasmids. All iPSC lines have a normal karyotype, express pluripotent genes including POU5F1, NANOG, and show alkaline phosphatase activity, as well as the ability to differentiate into all three germ layers. These PD iPSC lines can be used for disease modeling to identify PD mechanisms and for the development or stratification of new drugs.

Generation of an induced pluripotent stem cell line (EURACi005-A) from a Parkinson's disease patient carrying a homozygous exon 3 deletion in the PRKNgene.

Mutations in the PRKN gene, encoding parkin, are the most frequent known cause of recessive Parkinson's disease (PD). We report the generation of an induced pluripotent stem cell (iPSC) line of a patient carrying a homozygous deletion of exon 3 in the PRKN gene. Skin fibroblasts were reprogrammed using non-integrating episomal plasmids. The generated cell line (EURACi005-A; iPS-2011) exhibits expression of pluripotency markers, the potential to differentiate into all three germ layers, and a stable karyotype. This iPSC line provides a valuable resource for further research on the pathomechanism and drug testing for PRKN-linked PD.

A six-inhibitor culture medium for improving na\xefve-type pluripotency of porcine pluripotent stem cells

Understanding essential signaling network requirements and making appropriate adjustments in culture conditions are crucial if porcine pluripotent stem cells (PSC) are to achieve their full potential. Here, we first used two protein factors (LIF and FGF2) and kinase inhibitor combinations in attempts to convert primed type lentiviral-reprogrammed porcine induced PSC (Lv-piPSC) into naïve-like state and developed a medium called FL6i. In addition to FGF2 and LIF, this medium contained inhibitors of MAPK14, MAPK8, TGFB1, MAP2K1, GSK3A and BMP. Crucially, the usual TGFB1 and BMP4 protein components of many stem cell media were replaced in FL6i with inhibitors of TGFB1 and BMP. With this medium, Lv-piPSC were readily transformed from their original primed state into cells that formed colonies with typical features of naïve-state stem cells. The FL6i medium also assisted generation of naïve-type piPSC lines from porcine embryonic fibroblasts with non-integrating episomal plasmids (Epi-piPSC). These lines, despite retaining variable amounts of vector DNA, expressed higher endogenous pPOU5F1 and pSOX2 than Lv-piPSC. They have been cultured without obvious morphological change for >45 passages and retained pluripotent phenotypes in terms of upregulation of genes associated with pluripotency, low expression of genes linked to emergence of somatic cell lineages, and ability to generate well differentiated teratomas in immune-compromised mice. FL6i conditions, therefore, appear to support elevated pluripotent phenotypes. However, FL6i was less able to support the generation of embryonic stem cells from porcine blastocysts. Although colonies with dome-shaped morphologies were evident and the cells had some gene expression features linked to pluripotency, the phenotypes were ultimately not stable. Pathway analysis derived from RNAseq data performed on the various cell lines generated in this study suggest the benefits of employing the FL6i medium on porcine cells reside in its ability to minimize TGFB1 and BMP signaling, which would otherwise de-stabilize the stem cell state.

Biliary Atresia Relevant Human Induced Pluripotent Stem Cells Recapitulate Key Disease Features in a Dish.

ABSTRACTBiliary atresia (BA) is the most common cause of pediatric end-stage liver disease and the etiology is poorly understood. There is no effective therapy for BA partly due to lack of human BA models. Towards developing in vitro human models of BA, disease-specific induced pluripotent stem cells (iPSCs) from 6 BA patients were generated using non-integrating episomal plasmids. In addition, to determine the functional significance of BA-susceptibility genes identified by genome-wide association studies (GWAS) in biliary development, a genome-editing approach was used to create iPSCs with defined mutations in these GWAS BA loci. Using the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 system, isogenic iPSCs deficient in BA-associated genes (GPC1 and ADD3) were created from healthy iPSCs. Both the BA patient-iPSCs and the knock out (KO) iPSCs were studied for their in vitro biliary differentiation potential. These BA-specific iPSCs demonstrated significantly decreased formation of ductal structures, decreased expression of biliary markers including CK7, EpCAM, SOX9, CK19, AE2, and CFTR and increased fibrosis markers such as alpha smooth muscle actin, Loxl2, and Collagen1 compared to controls. Both the patient- and the KO-iPSCs also showed increased yes-associated protein (YAP, a marker of bile duct proliferation/fibrosis). Collagen and YAP were reduced by treatment with the anti-fibrogenic drug pentoxifylline. In summary, these BA-specific human iPSCs showed deficiency in biliary differentiation along with increased fibrosis, the 2 key disease features of BA. These iPSCs can provide new human BA models for understanding the molecular basis of abnormal biliary development and opportunities to identify drugs that have therapeutic effects on BA.

Generation and characterization of a human iPSC line from an ALS patient carrying the Q66K-MATR3 mutation

Fibroblasts isolated from an Amyotrophic Lateral Sclerosis (ALS)-patient carrying a mutation in Matrin-3 (p.Q66K -MATR3) gene were reprogrammed to the pluripotency stage by using non-integrating episomal plasmids. We generated the Q66K#44DRM induced pluripotent stem cell (iPSC) line that showed regular karyotype, expressed pluripotency-associated markers and were able to properly differentiate into the three germ layers. The heterozygous missense mutation in the MATR3 gene (p.Q66K), which is associated to ALS disease, was present in the generated iPSC line.Resource tableUnlabelled TableUnique stem cell line identifierCIBIOi001-AAlternative name(s) of stem cell lineQ66K#44DRMInstitutionCIBIO, University of Trento, ItalyContact information of distributorAlessandro Provenzani alessandro.provenzani@unitn.itType of cell lineiPSCs (induced pluripotent stem cells)OriginHumanAdditional origin infoAge:51Sex: MaleEthnicity if known: European, Italian.Cell sourcePatient derived fibroblastsClonalityClonal, clone number 44Method of reprogrammingEpisomal iPSC Reprogramming PlasmidGenetic modificationNOType of modificationSpontaneous mutation (missense)Associated diseaseAmyotrophic Lateral Sclerosis (ALS)Gene/locusMATR3/5q31.2Method of modificationN/AName of transgene or resistanceN/AInducible/constitutive systemN/ADate archived/stock date16/01/2018Cell line repository/bankN/AEthical approvalPatient signed informed consent, number of protocol P/740/CE/2012 released by the ethical committee of the Catholic University School of Medicine

Human Gingival Integration-Free iPSCs; a Source for MSC-Like Cells.

Mesenchymal stem cells (MSCs) are considered a potential autologous therapy for tissue engineering. The available procedures for MSC retrieval from patients are invasive, and their limited in vitro proliferation restricts their use in the treatment of damaged tissues. Therefore, it is important to establish an alternative and safe source of MSCs. The objective of this study was to demonstrate induced pluripotent stem cell (iPSC) generation from a combination of an accessible source tissue and an integration-free method; we also attempted the differentiation of iPSCs into MSC-like cells (MSLCs) for future autologous tissue engineering. iPSCs were derived from human gingival tissues, which are easily accessible in the field of dentistry, via the use of non-integrating episomal plasmids. Established iPSCs expressed embryonic stem (ES) cell-specific markers, as assessed by gene analysis and immunocytochemistry. Embryoid bodies and teratoma formation were formed from iPSCs, showing their capacity to differentiate into three germ layers. Furthermore, we were successful in differentiating iPSCs into MSLCs. They tested positively for their capacity of trilineage differentiation. Our results demonstrate that human gingival integration-free iPSCs, readily accessible stem cells generated using episomal plasmid vectors, are a promising source of MSLCs, which can be used in tissue regeneration.

Generation of Induced Pluripotent Stem Cells from Frozen Buffy Coats using Non-integrating Episomal Plasmids.

Somatic cells can be reprogrammed into induced pluripotent stem cells (iPSCs) by forcing the expression of four transcription factors (Oct-4, Sox-2, Klf-4, and c-Myc), typically expressed by human embryonic stem cells (hESCs). Due to their similarity with hESCs, iPSCs have become an important tool for potential patient-specific regenerative medicine, avoiding ethical issues associated with hESCs. In order to obtain cells suitable for clinical application, transgene-free iPSCs need to be generated to avoid transgene reactivation, altered gene expression and misguided differentiation. Moreover, a highly efficient and inexpensive reprogramming method is necessary to derive sufficient iPSCs for therapeutic purposes. Given this need, an efficient non-integrating episomal plasmid approach is the preferable choice for iPSC derivation. Currently the most common cell type used for reprogramming purposes are fibroblasts, the isolation of which requires tissue biopsy, an invasive surgical procedure for the patient. Therefore, human peripheral blood represents the most accessible and least invasive tissue for iPSC generation. In this study, a cost-effective and viral-free protocol using non-integrating episomal plasmids is reported for the generation of iPSCs from human peripheral blood mononuclear cells (PBMNCs) obtained from frozen buffy coats after whole blood centrifugation and without density gradient separation.

Generation of Induced Pluripotent Stem Cells from Frozen Buffy Coats using Non-integrating Episomal Plasmids

Generation of Induced Pluripotent Stem Cells from Frozen Buffy Coats using Non-integrating Episomal Plasmids

A Universal System for Highly Efficient Cardiac Differentiation of Human Induced Pluripotent Stem Cells That Eliminates Interline Variability

BackgroundThe production of cardiomyocytes from human induced pluripotent stem cells (hiPSC) holds great promise for patient-specific cardiotoxicity drug testing, disease modeling, and cardiac regeneration. However, existing protocols for the differentiation of hiPSC to the cardiac lineage are inefficient and highly variable. We describe a highly efficient system for differentiation of human embryonic stem cells (hESC) and hiPSC to the cardiac lineage. This system eliminated the variability in cardiac differentiation capacity of a variety of human pluripotent stem cells (hPSC), including hiPSC generated from CD34+ cord blood using non-viral, non-integrating methods.Methodology/Principal FindingsWe systematically and rigorously optimized >45 experimental variables to develop a universal cardiac differentiation system that produced contracting human embryoid bodies (hEB) with an improved efficiency of 94.7±2.4% in an accelerated nine days from four hESC and seven hiPSC lines tested, including hiPSC derived from neonatal CD34+ cord blood and adult fibroblasts using non-integrating episomal plasmids. This cost-effective differentiation method employed forced aggregation hEB formation in a chemically defined medium, along with staged exposure to physiological (5%) oxygen, and optimized concentrations of mesodermal morphogens BMP4 and FGF2, polyvinyl alcohol, serum, and insulin. The contracting hEB derived using these methods were composed of high percentages (64–89%) of cardiac troponin I+ cells that displayed ultrastructural properties of functional cardiomyocytes and uniform electrophysiological profiles responsive to cardioactive drugs.Conclusion/SignificanceThis efficient and cost-effective universal system for cardiac differentiation of hiPSC allows a potentially unlimited production of functional cardiomyocytes suitable for application to hPSC-based drug development, cardiac disease modeling, and the future generation of clinically-safe nonviral human cardiac cells for regenerative medicine.