Large-Scale Automated Hollow-Fiber Bioreactor Expansion of Umbilical Cord-Derived Human Mesenchymal Stromal Cells for Neurological Disorders.

Neurodegenerative disorders present a broad group of neurological diseases and remain one of the greatest challenges and burdens to mankind. Maladies like amyotrophic lateral sclerosis, Alzheimer's disease, stroke or spinal cord injury commonly features astroglia involvement (astrogliosis) with signs of inflammation. Regenerative, paracrine and immunomodulatory properties of human mesenchymal stromal cells (hMSCs) could target the above components, thus opening new therapeutic possibilities for regenerative medicine. A special interest should be given to hMSCs derived from the umbilical cord (UC) tissue, due to their origin, properties and lack of ethical paradigms. The aim of this study was to establish standard operating and scale-up good manufacturing practice (GMP) protocols of UC-hMSCs isolation, characterization, expansion and comparison of cells' properties when harvested on T-flasks versus using a large-scale bioreactor system. Human UC-hMSCs, isolated by tissue explant culture technique from Wharton's jelly, were harvested after reaching 75% confluence and cultured using tissue culture flasks. Obtained UC-hMSCs prior/after the cryopreservation and after harvesting in a bioreactor, were fully characterized for "mesenchymness" immunomodulatory, tumorigenicity and genetic stability, senescence and cell-doubling properties, as well as gene expression features. Our study demonstrates an efficient and simple technique for large scale UC-hMSCs expansion. Harvesting of UC-hMSCs' using classic and large scale methods did not alter UC-hMSCs' senescence, genetic stability or in vitro tumorigenicity features. We observed comparable growth and immunomodulatory capacities of fresh, frozen and expanded UC-hMSCs. We found no difference in the ability to differentiate toward adipogenic, osteogenic and chondrogenic lineages between classic and large scale UC-hMSCs expansion methods. Both, methods enabled derivation of genetically stabile cells with typical mesenchymal features. Interestingly, we found significantly increased mRNA expression levels of neural growth factor (NGF) and downregulated insulin growth factor (IGF) in UC-hMSCs cultured in bioreactor, while IL4, IL6, IL8, TGFb and VEGF expression levels remained at the similar levels. A culturing of UC-hMSCs using a large-scale automated closed bioreactor expansion system under the GMP conditions does not alter basic "mesenchymal" features and quality of the cells. Our study has been designed to pave a road toward translation of basic research data known about human UC-MSCs for the future clinical testing in patients with neurological and immunocompromised disorders. An industrial manufacturing of UC-hMSCs next will undergo regulatory approval following advanced therapy medicinal products (ATMP) criteria prior to clinical application and approval to be used in patients.

Generation of two Duchenne muscular dystrophy patient-specific induced pluripotent stem cell lines DMD02 and DMD03 (MUNIi001-A and MUNIi003-A).

Duchenne muscular dystrophy (DMD) affects 1:3500-5000 newborn boys and manifests with progressive skeletal muscle wasting, respiratory failure and eventual heart failure. Symptoms show different onset from patients' childhood to the second decade of age. We reprogrammed fibroblasts from two independent DMD patients with a complete loss of dystrophin expression, carrying deletions of exons 45-50 and 48-50. The resulting hiPSCs show expression of pluripotency markers (NANOG, OCT4, SSEA4), differentiation capacity into all three germ layers, normal karyotype, genetic identity to the originating parental fibroblasts and the patient-specific dystrophin mutation.

Novel de novo frameshift variant in the ASXL3 gene in a child with microcephaly and global developmental delay.

De novo sequence variants, including truncating and splicing variants, in the additional sex­combs like 3 gene (ASXL3) have been described as the cause of Bainbridge­Ropers syndrome (BRS). This pathology is characterized by delayed psychomotor development, severe intellectual disability, growth delay, hypotonia and facial dimorphism. The present study reports a case of a girl (born in 2013) with severe global developmental delay, central hypotonia, microcephaly and poor speech. The proband was examined using a multi­step molecular diagnostics algorithm, including karyotype and array­comparative genomic hybridization analysis, with negative results. Therefore, the proband and her unaffected parents were enrolled for a pilot study using targeted next­generation sequencing technology (NGS) with gene panel ClearSeq Inherited DiseaseXT and subsequent validation by Sanger sequencing. A novel de novo heterozygous frameshift variant in the ASXL3 gene (c.3006delT, p.R1004Efs*21), predicted to result in a premature termination codon, was identified. In conclusion, the present study demonstrated that targeted NGS using a suitable, gene­rich panel may provide a conclusive molecular genetics diagnosis in children with severe global developmental delays.

Monozygotic twins with discordant karyotypes following preimplantation genetic screening and single embryo transfer: case report.

PURPOSE: to report a case of monozygotic monochorial diamniotic twins with discordant karyotypes. METHODS AND RESULTS: the pregnancy was achieved following a treatment cycle with intracytoplasmic sperm injection (ICSI) and preimplantation genetic screening (PGS) for chromosomes X, Y, 13, 16, 18, 21, 22. One embryo euploid for studied chromosomes was transferred. Prenatal ultrasonography revealed monozygotic twins. One fetus had growth retardation, multiple organ abnormalities and polyhydramnion. The other twin had normal ultrasound appearance. Delivery on week 29 of gestation resulted in the birth of two females, a stillborn twin with karyotype 45,XX,-13[12]/46,XX,r(13)[3] and a healthy twin with normal karyotype. CONCLUSIONS: the discordance in the twins' karyotypes originated from a mosaic embryo. Structural chromosomal abnormality of the affected twin could not be revealed using standard PGS investigation. Embryo splitting occurred probably due to apoptotic process in an early stage of embryo development. Apoptosis represents one of the possible mechanisms which can explain the embryo twinning process globally.