Generation of two induced pluripotent stem cell lines (UQACi002-A and UQACi005-A) from two patients with KRT14 epidermolysis bullosa simplex mutations.

More than 107 pathogenic variations were identified in Keratin 14 gene (KRT14) in patients affected by epidermolysis bullosa simplex (EBS), a rare skin disease with still no curative treatment. Disease models as human induced pluripotent stem cells (hiPSCs) are promising tool for further advance the knowledge about this disorder and accelerate therapies development. Here, two hiPSC lines were reprogrammed from skin fibroblasts of two EBS patients carrying mutations within KRT14 by using CytoTune®Sendai virus. These iPSCs display pluripotent cell morphology, pluripotent markers expression, and the capability to differentiate into the three germ layers.

Generation of three induced pluripotent stem cell lines (UQACi003-A, UQACi004-A, and UQACi006-A) from three patients with KRT5 epidermolysis bullosa simplex mutations.

Heterozygous mutations within Keratin 5 (KRT5) are common genetic causes of epidermolysis bullosa simplex (EBS), a skin fragility disorder characterized by blisters, which appear after minor trauma. Using CytoTune®Sendai virus, we generated three human induced pluripotent stem cell (iPSC) lines from three EBS patients carrying respectively the single heterozygous mutations in KRT5, c.449 T > C, c.980 T > C, and c.608 T > C. All lines display normal karyotype, expressed high levels of pluripotent markers, and can differentiate into derivatives of the three germ layers. These iPSCs are helpful for a better understanding of the EBS pathogenesis and developing novel therapeutic approaches.

Generation of a human induced pluripotent stem cell line (UQACi001-A) from a severe epidermolysis bullosa simplex patient with the heterozygous mutation p.R125S in the KRT14 gene.

We have generated UQACi001-A, a new induced pluripotent stem cell (iPSC) line derived from skin fibroblasts of a male patient with the generalized severe epidermolysis bullosa simplex phenotype (EBS-gen sev) and carrying the keratin 14 (K14) R125S mutation. Fibroblasts were reprogrammed using non-integrating Sendai virus vectors. The iPSC line displayed normal molecular karyotype, expressed pluripotency markers, is capable of differentiating into three embryonic germ layers and is genetically identical to the originating parental fibroblasts. The established iPSC model provides a valuable resource for studying the rare disease of epidermolysis bullosa simplex and developing new therapies as DNA editing by CRISPR/Cas9 technology.

Differentiation of lymphoblastoid-derived iPSCs into functional cardiomyocytes, neurons and myoblasts.

Human induced pluripotent stem cells (hiPSCs) are a valuable tool for investigating complex cellular and molecular events that occur in several human diseases. Importantly, the ability to differentiate hiPSCs into any human cell type provides a unique way for investigating disease mechanisms such as complex mental health diseases. The in vitro transformation of human lymphocytes into lymphoblasts (LCLs) using the Epstein-Barr virus (EBV) has been the main method for generating immortalized human cell lines for half a century. However, the derivation of iPSCs from LCLs has emerged as an alternative source from which these cell lines can be generated. We show that iPSCs derived from LCLs using the Sendai virus procedure can be successfully differentiated into cardiomyocytes, neurons, and myotubes that express neuron- and myocyte-specific markers. We further show that these cardiac and neuronal cells are functional and generate action potentials that are required for cell excitability. We conclude that the ability to differentiate LCLs into neurons and myocytes will increase the use of LCLs in the future as a potential source of cells for modelling a number of diseases.

Lymphoblastoids cell lines - Derived iPSC line from a 26-year-old myotonic dystrophy type 1 patient carrying (CTG)200 expansion in the DMPK gene: CHUQi001-A.

Human immortalized Epstein-Barr virus (EBV) lymphoblastoids cells line (LCLs) from a 26-year- old male affected by an adult form of myotonic dystrophy type 1 (DM1) disease and carrying 200 CTG repeats mutation in the blood was used to generate induced pluripotent stem cells (iPSCs) using the Sendai virus expressing KLF4, OCT4, SOX2 and C-MYC. The resulting iPSCs were EBV free, expressed the pluripotency markers, could be differentiated into the three germ layers in vitro, had a normal karyotype, and retained the genetic DM1 mutation. This iPSC line could be useful for the investigation of DM1 mechanisms.

Targeting DMPK with Antisense Oligonucleotide Improves Muscle Strength in Myotonic Dystrophy Type 1 Mice.

Myotonic dystrophy type 1 (DM1), a dominant hereditary muscular dystrophy, is caused by an abnormal expansion of a (CTG)n trinucleotide repeat in the 3' UTR of the human dystrophia myotonica protein kinase (DMPK) gene. As a consequence, mutant transcripts containing expanded CUG repeats are retained in nuclear foci and alter the function of splicing regulatory factors members of the MBNL and CELF families, resulting in alternative splicing misregulation of specific transcripts in affected DM1 tissues. In the present study, we treated DMSXL mice systemically with a 2'-4'-constrained, ethyl-modified (ISIS 486178) antisense oligonucleotide (ASO) targeted to the 3' UTR of the DMPK gene, which led to a 70% reduction in CUGexp RNA abundance and foci in different skeletal muscles and a 30% reduction in the heart. Furthermore, treatment with ISIS 486178 ASO improved body weight, muscle strength, and muscle histology, whereas no overt toxicity was detected. This is evidence that the reduction of CUGexp RNA improves muscle strength in DM1, suggesting that muscle weakness in DM1 patients may be improved following elimination of toxic RNAs.

Angiogenic response of endothelial cells seeded dispersed versus on beads in fibrin gels.

Induction of an inter-connected microvessel network in a tissue-engineered construct prior to implantation may be an alternative to improve the success rate of cell/tissue survival and wound integration. Conditions of endothelial cell-seeding density and distribution were investigated in two 3-D angiogenesis culture systems. Endothelial cells were either seeded dispersed in a fibrin gel, or subconfluent on micro-beads (Cytodex) prior to being embedded in fibrin. Human fibroblasts and growth factors were introduced to optimize angiogenesis. A density higher than 4 x 10(4) cells/ml of fibrin was necessary to induce angiogenic-like structures (i.e., sprouting, cord-, lumen-like structures) by 14 days in the dispersed cell model. Endothelial cells on micro-beads also exhibited angiogenic-like structures that were inter-connected to those on neighboring beads. The sizes of the angiogenic-like structures were larger on beads compared to those found in the dispersed cell model. High cell density was needed in angiogenesis when cells were seeded separately, whereas the association of endothelial cells on bead surfaces significantly reduced the cell density used. Moreover, increasing bead density was not necessary to facilitate further angiogenic formation. Micro-spheres may represent a potential support for endothelial cells in microvessel networking, with subsequent applications in the pre-vascularization of bio-implants.