جستجوی مقالات مرتبط با کلیدواژه « سلول های بنیادی پرتوان القایی » در نشریات گروه « پزشکی »

Multiple Sclerosis (MS) is a neurodegenerative inflammatory disease with a wide range of axonal demyelination and sensory-motor disorders. Today, stem cell therapy is an appropriate choice for MS management. Induced Pluripotent Stem Cells (iPSC) are pluripotent stem cells that have neuroprotective effects with neuroglial differentiation potential. In this study, we used iPSCs to improve remyelination and behavioral function in model of cuprizone multiple sclerosis disease in rats.

Human iPSCs were cultured and extended on a mouse embryonic fibroblast feeder cell layer inactivated with mitomycin-C in DMEM/F12 supplemented with 20% knockout serum replacement, 0.1 mmol/L nonessential amino acids, and 10 ng/mL of recombinant human basic fibroblast growth factor in a 5% CO2 and 95% humidity. The demyelination model was induced using a 0.2 oral Cuprizone regime. Thereafter, iPSCs were transplanted after six weeks. Remyelination was investigated via histological assessments and immunocytochemistry following six-week post-transplantation. The functionality was evaluated using behavioral tests, BBB, and Footprint following six-week post-transplantation.

The results of in vivo studies showed that after specific myelin tissue staining, the cuprizone diet led to the induction of demyelinated areas in the brain tissue six weeks after the cuprizone diet. Differentiation of transplanted cells was confirmed via the immunocytochemistry technique of PLP. The results of the Footprint test showed that the motor function of the paws of the animals improved compared to the control group. Moreover, BBB behavioral tests showed improved symptoms in the experimental groups that received the cells.

In total, iPSCs can improve remyelination and functional recovery following transplantation into the Cuprizone demyelination model in rats. Therefore, iPSC therapy could improve behavioral function in multiple sclerosis disease

Schizophrenia (SZ) is a widespread, chronic, and developmental mental disorder resulting from disruption in neural connections. SZ causes social and occupational disabilities, including a wide range of mental disorders that can lead to improper behaviors. Over 1% of the world's population has been affected by SZ which is mostly characterized by distortions in thinking, perception, emotion, language, and behavior. This disorder has been accompanied by other mental problems, such as anxiety, depression, or addiction. An emerging hypothesis suggests a central role of dysregulation of Ca2+ homeostasis in the pathophysiology of SZ. Numerous intracellular signals initiated by Ca2+ ions are responsible for modulating neuronal excitability, information processing, and cognition. Ca2+ signaling and homeostasis impairment in glutamatergic, GABAergic, and dopaminergic neurons are early characteristics of SZ. The discovery of human induced pluripotent stem cells (iPSC) offers a novel and promising patient-specific cellular disease model for SZ. However, the central role of Ca2+ homeostasis and the detailed mechanisms in SZ using the iPSCs model still needs further investigation. Here, we explore the current understanding of Ca2+ homeostasis and iPSCs model-based studies in SZ, as well as potential future directions to identify robust and valid cellular phenotypes for drug testing and development.

The iPSCs model is a powerful tool for elucidating the mechanism of Ca2+ homeostasis, understanding SZ pathophysiology, and drug development.

Chick embryos are a great historical research model in basic and applied sciences. Along with other animal models, avian and specifically chicken embryo has been attended, as well. Avian fertilized eggs as a natural bioreactor are an efficient tool for producing recombinant proteins and vaccines manufacturing. Due to the limitations of birds' eggs for viral replication, avian stem cells culture technologies access to safe methods as well as large-scale production of a variety of human and animal vaccines. Chicken pluripotent stem cells present the unique property of self-renewal and the ability to generate differentiated progeny in all embryonic lineages such as ectoderm, mesoderm, and endoderm in vitro. For the first time, chicken embryonic stem cells (cESCs) derived from the blastodermal cells of stage X embryos in vitro. Chicken ESC provides a great model of early embryo and they are useful for gene manipulation, virus proliferation, and the generation of transgenic birds. In addition to blastodermal cells, pluripotent cell lines can be produced by reprogramming of chicken fibroblasts into induced pluripotent stem cells (iPSCs) with transcription factors such as OCT4, NANOG, SOX2, KLF4, LIN28, and C-MYC that are well known to contribute to the reprogramming of somatic cells into an iPSCs. Similar to chicken ESCs, iPSCs have properties of unlimited self-renewal in vitro and the capacity for differentiation to all three embryonic germ layers. Chicken iPSCs have been a useful tool for the production of transgenic birds and viral vaccines. Despite the benefits and multiple applications of chicken pluripotent stem cells, the propagation of these cells is limited and some important challenges should be eliminated before their use in vaccine manufacturing. It is necessary to define the appropriate culture conditions for chicken pluripotent stem cells. For example, the presence of endogenous viruses in the avian species should be evaluated for human vaccine production. Currently, primary chicken fibroblast cells are still mainly used for vaccine production. This review covers the resources to achieve chicken derived cell lines for vaccine manufacturing.

Embryonic stem cells are pluripotent stem cells which have the ability to indefinitely self-renew and differentiate into all differentiated cells of the body. Regarding their two main properties (unlimited self-renewal and multi-lineage differentiation), these cells have various biomedical applications in basic research and cell based therapy. Because the transplantation of differentiated cells that are derived from embryonic stem cells is allogenic, they face the problem of immune rejection following the transplantation of embryonic stem cell-derived cells into patients. In 2006, researchers from Japan reported the derivation of a new type of pluripotent stem cells which could overcome the problem of immune rejection that is associated with the application of embryonic stem cells. They designated these cells as induced pluripotent stem (iPS) cells, because their production was ‘induced’ from differentiated somatic cells using a combination of four embryonic stem cell-associated transcription factors. Importantly, these pluripotent stem cells exhibit all the key features of embryonic stem cells including unlimited self-renewal and multi-lineage differentiation potential, and can pass the most stringent test of pluripotency which is known as the tetraploid (4n) complementation. Hence, in addition to bypassing the problem of immune rejection, iPS cells have all of the potential applications of embryonic stem cells, including in developmental studies, toxicology research, drug discovery and disease modeling. Also, considering that they could be generated from patient’s own cells, iPS cells hold great promise in the future of patient-specific cell replacement therapies using pluripotent stem cells. In this review article, we will present a comprehensive review on the how and why of the generation of iPS cell from somatic cells of the body and discuss how they should be characterized in terms of morphologically, pluripotent stem cell behavior, and the molecular signature. In addition, their medical applications as well as some of the considerations and future challenges in their use will be discussed.

The ability to induce pluripotency in somatic cells by reprogramming factors offers new opportunities for drug discovery and cell therapy. Induced pluripotent stem cells have the potential to differentiate to various cell types, such as neural and glial cells. Astrocytes, the major glial cells of the central nervous system, play an important role in the function of the brain by regulating of extracellular ions and neurotransmitters, feeding and protection of neurons as well as modulating the activity of microglia. Microglia over-activation can be resulted in brain inflammation with subsequent susceptibility to epileptic seizures. Hypothesis: For many years, embryonic Stem cell transplantation has been examined to prevent seizure attacks in epilepsy. These studies have indicated that adult cells from patient have the ability to be transformed to embryonic stage and convert to a pluripotent stem cell by using some Transcription factors (such as Oct4, Sox2, Nanog, Rex1, Klf, c-Myc and LIN28). Accordingly, fibroblasts from an epileptic have also been reprogrammed to embryonic stage. The resulting iPS cells are isogenic to patient and are able to transform to neurons or glia in a suitable culture condition. Previous studies on ES cell therapy have focused more on neurons than astrocytes. Astrocytes, by secretion of glial cell-derived neurotrophic factor, not only regulate the different microglial activities, such as proliferation, migration and cell adhesion, but can also reduce destructive effects of microglia.
In this hypothesis, we suggest a reprogramming system for generating functional astrocyte from human pluripotent stem cell in the presence of neural growth factors. We hypothesize that these cells might reduce neuroinflammation induced by microglia and subsequent susceptibility to seizure. The reprogrammed cells could be used in cell replacement therapy of epilepsy.