Generation of iPSC lines (KAIMRCi003A, KAIMRCi003B) from a Saudi patient with Dravet syndrome carrying homozygous mutation in the CPLX1 gene and heterozygous mutation in SCN9A.

The most prevalent form of epileptic encephalopathy is Dravet syndrome (DRVT), which is triggered by the pathogenic variant SCN1A in 80% of cases. iPSCs with different SCN1A mutations have been constructed by several groups to model DRVT syndrome. However, no studies involving DRVT-iPSCs with rare genetic variants have been conducted. Here, we established two DRVT-iPSC lines harboring a homozygous mutation in the CPLX1 gene and heterozygous mutation in SCN9A gene. Therefore, the derivation of these iPSC lines provides a unique cellular platform to dissect the molecular mechanisms underlying the cellular dysfunctions consequent to CPLX1 and SCN9A mutations.

HLA-based banking of induced pluripotent stem cells in Saudi Arabia.

BACKGROUND: Human iPSCs' derivation and use in clinical studies are transforming medicine. Yet, there is a high cost and long waiting time associated with autologous iPS-based cellular therapy, and the genetic engineering of hypo-immunogenic iPS cell lines is hampered with numerous hurdles. Therefore, it is increasingly interesting to create cell stocks based on HLA haplotype distribution in a given population. This study aimed to assess the potential of HLA-based iPS banking for the Saudi population. METHODS: In this study, we interrogated the HLA database of the Saudi Stem Cell Donor Registry (SSCDR), containing high-resolution HLA genotype data from 64,315 registered Saudi donors at the time of analysis. This database was considered to be a representative sample of the Saudi population. The most frequent HLA haplotypes in the Saudi population were determined, and an in-house developed iterative algorithm was used to identify their HLA matching percentages in the SSCDR database and cumulative coverage. Subsequently, to develop a clinically relevant protocol for iPSCs generation, and to illustrate the applicability of the concept of HLA-based banking for cell therapy purposes, the first HLA-based iPS cell line in Saudi Arabia was generated. Clinically relevant methods were employed to generate the two iPS clones from a homozygous donor for the most prevalent HLA haplotype in the Saudi population. The generated lines were then assessed for pluripotency markers, and their ability to differentiate into all three germ layers, beating cardiomyocytes, and neural progenitors was examined. Additionally, the genetic stability of the HLA-iPS cell lines was verified by comparing the mutational burden in the clones and the original blood sample, using whole-genome sequencing. The standards set by the American College of Medical Genetics and Genomics (ACMG) were used to determine the clinical significance of identified variants. RESULTS: The analysis revealed that the establishment of only 13 iPSC lines would match 30% of the Saudi population, 39 lines would attain 50% coverage, and 596 lines would be necessary for over 90% coverage. The proof-of-concept HLA-iPSCs, which cover 6.1% of the Saudi population, successfully demonstrated pluripotency and the ability to differentiate into various cell types including beating cardiomyocytes and neuronal progenitors. The comprehensive genetic analysis corroborated that all identified variants in the derived iPSCs were inherently present in the original donor sample and were classified as benign according to the standards set by the ACMG. CONCLUSIONS: Our study sets a road map for introducing iPS-based cell therapy in the Kingdom of Saudi Arabia. It underscores the pragmatic approach of HLA-based iPSC banking which circumvents the limitations of autologous iPS-based cellular therapies. The successful generation and validation of iPSC lines based on the most prevalent HLA haplotype in the Saudi population signify a promising step toward broadening the accessibility and applicability of stem cell therapies and regenerative medicine in Saudi Arabia.

Generation of myoglobin (MB)-knockout human embryonic stem cell (hESC) line (KAIMRCe002-A-1S) using CRISPR/Cas9 technology.

Myoglobin (MB) is a cytoplasmic hemoprotein that is predominantly expressed in the heart and oxidative myofibers of skeletal muscle. It has been demonstrated that MB binds to oxygen and promotes its diffusion for energy production in the mitochondria. Recently, MB was found to be expressed in different forms of malignant tumors and cancer cell lines. Further studies using gene disruption technology will enhance the understanding of MB's role in human cardiovascular biology and cancers. Here, we describe the generation of a homozygous MB knockout in human embryonic stem cells (hESC-MB-/-) via CRISPR/Cas9 to study MB function in human biology and diseases.

Generation of induced pluripotent stem cell Line KAIMRCi001-A by reprogramming erythroid progenitors from peripheral blood of a healthy Saudi donor.

In this study we isolated and enriched erythroid progenitor cells (EPCs) from a 10 ml peripheral blood sample from a 37-year old healthy Saudi donor. After expansion, these EPCs were reprogrammed using episomal plasmids to generate an induced pluripotent stem (iPS) cell line, KAIMRCi001-A. The pluripotency of this line was confirmed by measuring the expression of typical pluripotency markers and assessing differentiation potential in vitro.