Generation of induced pluripotent stem cell line (ZZUi005-A) from a 21-year-old patient with a novel RAB39B gene mutation in X-linked juvenile parkinsonism

The occurrence and development of induced pluripotent stem cells

The ectopic expression of four transcription factors, Oct3/4, Sox2, Klf4, and c-Myc (OSKM), known as "Yamanaka factors," can reprogram or stimulate the production of induced pluripotent stem cells (iPSCs). Although OSKM is still the gold standard, there are multiple ways to reprogram cells into iPSCs. In recent years, significant progress has been made in improving the efficiency of this technology. Ten years after the first report was published, human pluripotent stem cells have gradually been applied in clinical settings, including disease modeling, cell therapy, new drug development, and cell derivation. Here, we provide a review of the discovery of iPSCs and their applications in disease and development.

The Role of Rab GTPases in the development of genetic and malignant diseases

Small GTPases have been shown to play an important role in several cellular functions, including cytoskeletal remodeling, cell polarity, intracellular trafficking, cell-cycle, progression and lipid transformation. The Ras-associated binding (Rab) family of GTPases constitutes the largest family of GTPases and consists of almost 70 known members of small GTPases in humans, which are known to play an important role in the regulation of intracellular membrane trafficking, membrane identity, vesicle budding, uncoating, motility and fusion of membranes. Mutations in Rab genes can cause a wide range of inherited genetic diseases, ranging from neurodegenerative diseases, such as Parkinson's disease (PD) and Alzheimer's disease (AD) to immune dysregulation/deficiency syndromes, like Griscelli Syndrome Type II (GS-II) and hemophagocytic lymphohistiocytosis (HLH), as well as a variety of cancers. Here, we provide an extended overview of human Rabs, discussing their function and diseases related to Rabs and Rab effectors, as well as focusing on effects of (aberrant) Rab expression. We aim to underline their importance in health and the development of genetic and malignant diseases by assessing their role in cellular structure, regulation, function and biology and discuss the possible use of stem cell gene therapy, as well as targeting of Rabs in order to treat malignancies, but also to monitor recurrence of cancer and metastasis through the use of Rabs as biomarkers. Future research should shed further light on the roles of Rabs in the development of multifactorial diseases, such as diabetes and assess Rabs as a possible treatment target.

Generation of induced pluripotent stem cell line (ZZUi015-A) from a DM1 patient with cataract

Myotonic dystrophy (DM1) is mainly caused by abnormal number of the CTG repeat sequence of the DMPK gene. DM1 clinically manifests mainly as progressive muscular atrophy and muscle weakness. Cataracts form in the eyes of some patients. We successfully induced skin fibroblasts from a DM1 patient with cataract and in turn induced pluripotent stem cells (iPSCs) using an unintegrated reprogramming approach. This cell line will provide a reliable cell model for further studies on the pathogenesis and potential therapeutic targets of DM1.

Generation of induced pluripotent stem cell line (ZZUi027-A) derived from skin fibroblasts from a Parkinson's disease patient with RAB39B gene mutation

Parkinson's disease is a common neurogenetic degenerative disease that can be caused by a variety of genetic mutations. RAB39B gene mutations have recently been identified as a cause of Parkinson's disease. We collected skin tissue samples from a family with mutations in RAB39B for our clinical study. Additionally, we constructed patient-derived induced pluripotent stem cells (iPSCs) from the patient's uncle using an unintegrated reprogramming plasmid transfection method to create a reliable cell model for the subsequent study of Parkinson's disease.

Generation of induced pluripotent stem cell line (ZZUi019-A) derived from skin fibroblasts from a healthy volunteer

The research on nervous system diseases is limited by the difficulty in obtaining nerve cells from humans. The development of induced pluripotent stem cells (iPSCs) technology and the experimental system provide a feasible method for directional induced differentiation of nerve cells in vitro. In this project, we recruited a 50-year-old Han Chinese man as a healthy volunteer, and successfully constructed his skin fibroblast-derived iPSCs using the non-integrated reprogramming method. At the same time, the related pluripotency identification experiments were completed. This cell line will be included in the normal control group in follow-up experiments, providing an important reference for the study of neurological diseases.

RAB39B's role in membrane traffic, autophagy, and associated neuropathology

Neuropathological disorders are increasingly associated with dysfunctions in neuronal membrane traffic and autophagy, with defects among members of the Rab family of small GTPases implicated. Mutations in the human Xq28 localized gene RAB39B have been associated with X-linked neurodevelopmental defects including macrocephaly, intellectual disability, autism spectrum disorder (ASD), as well as rare cases of early-onset Parkinson's disease (PD). Despite the finding that RAB39B regulates GluA2 trafficking and could thus influence synaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor subunit composition, reasons for the wide-ranging neuropathological consequences associated with RAB39B defects have been unclear. Recent studies have now unraveled possible mechanisms underlying the neuropathological roles of this brain-enriched small GTPase. Studies in RAB39B knockout mice showed that RAB39B interacts with components of Class I phosphatidylinositol-3-kinase (PI3K) signaling. In its absence, the PI3K-AKT-mechanistic target of rapamycin signaling pathway in neural progenitor cells (NPCs) is hyperactivated, which promotes NPC proliferation, leading to macrocephaly and ASD. Pertaining to early-onset PD, a complex of C9orf72, Smith-Magenis syndrome chromosome region candidate 8 and WD repeat domain 41 that functions in autophagy has been identified as a guanine nucleotide exchange factor of RAB39B. Here, recent findings that have shed light on our mechanistic understanding of RAB39B's role in neurodevelopmental and neurodegenerative pathologies are reviewed. Caveats and unanswered questions are also discussed, and future perspectives outlined.

Generation of induced pluripotent stem cell line (ZZUi011-A) from urine sample of a normal human

Urine cells collected from 200mL clean midsection urine of a 25-year-old healthy man were reprogrammed into pluripotent stem cells via Sendai virus delivery system. The induced pluripotent stem cells showed a normal karyotype and exhibited the potential to differentiate into three germ layers in a teratoma assay. This cell line may serve as a useful control for comparison with other pluripotent stem cell lines induced from somatic cells of patients with genetic neurodegenerative disorders.