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1.
Asian Journal of Andrology ; (6): 13-20, 2023.
Artículo en Inglés | WPRIM | ID: wpr-970987

RESUMEN

Infertility has become a serious disease since it affects 10%-15% of couples worldwide, and male infertility contributes to about 50% of the cases. Notably, a significant decrease occurs in the newborn population by 7.82 million in 2020 compared to 2016 in China. As such, it is essential to explore the effective methods of obtaining functional male gametes for restoring male fertility. Stem cells, including embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), spermatogonial stem cells (SSCs), and mesenchymal stem cells (MSCs), possess the abilities of both self-renewal and differentiation into germ cells. Significantly, much progress has recently been achieved in the generation of male germ cells in vitro from various kinds of stem cells under the specified conditions, e.g., the coculturing with Sertoli cells, three-dimensional culture system, the addition of growth factors and cytokines, and/or the overexpression of germ cell-related genes. In this review, we address the current advance in the derivation of male germ cells in vitro from stem cells based on the studies of the peers and us, and we highlight the perspectives and potential application of stem cell-derived male gametes in reproductive medicine.


Asunto(s)
Humanos , Recién Nacido , Masculino , Células Germinativas , Células Madre Embrionarias , Diferenciación Celular , Infertilidad Masculina , Células Madre Pluripotentes Inducidas
2.
Journal of Southern Medical University ; (12): 1125-1130, 2021.
Artículo en Chino | WPRIM | ID: wpr-888696

RESUMEN

OBJECTIVE@#To explore the role of small nuclear noncoding RNA 7SK in embryonic stem cell (ESCs) proliferation and the value of 7SK as a target for early diagnosis and treatment for primordial dwarfism (PD).@*METHODS@#ESC line R1 was transfected with the CRISPR/Cas9 system, and sequencing of the PCR product and glycerol gradient analysis were performed to identify novel 7SK deletion mutations. A lentivirus system was used to knock down cyclin-dependent kinase 9 (CDK9) in clones with 7SK deletion mutations, and the effect of CDK9 knockdown on the protein level of cell division cycle 6 (CDC6) was analyzed with Western blotting.@*RESULTS@#We identified a novel deletion mutation of 7SK at 128-179 nt in the ESCs, which resulted in deficiency of cell proliferation. 7SK truncation at 128-179 nt significantly reduced the protein expressions of La-related protein 7 (LARP7) and CDC6.@*CONCLUSIONS@#7SK truncation at 128-179 nt can significantly impair proliferation of ESCs by downregulating CDC6. 7SK is a key regulator of proliferation and mediates the growth of ESCs through a mechanism dependent on CDK9 activity, suggesting the value of 7SK truncation at 128-179 nt as a potential target for early diagnosis and treatment of PD.


Asunto(s)
Humanos , Proteínas de Ciclo Celular , Proliferación Celular , Células Madre Embrionarias/metabolismo , Células HeLa , Proteínas Nucleares , Factor B de Elongación Transcripcional Positiva/metabolismo , ARN Largo no Codificante/genética , Proteínas de Unión al ARN , Ribonucleoproteínas , Factores de Transcripción
3.
Chinese Journal of Biotechnology ; (12): 4001-4014, 2021.
Artículo en Chino | WPRIM | ID: wpr-921481

RESUMEN

Induced pluripotent stem cells (iPSCs) are a type of cells similar to embryonic stem cells but produced by reprogramed somatic cells. Through in vitro differentiation of iPSCs, we can interrogate the evolution history as well as the various characteristics of macrophages. iPSCs derived macrophages are not only a good model for drug screening, but also an important approach for immunotherapy. This review summarizes the advances, challenges, and future directions in the field of iPSCs-derived macrophages.


Asunto(s)
Diferenciación Celular , Células Madre Embrionarias , Células Madre Pluripotentes Inducidas , Macrófagos
4.
Braz. arch. biol. technol ; 63: e20200234, 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1132219

RESUMEN

Abstract Curcumin (CUR) shows potential use for treating cancer. However, CUR has low solubility and reduced bioavailability, which limit its clinical effect. Therefore, the development of nanocarriers can overcome these problems and can ensure the desired pharmacological effect. In addition, it is mandatory to prove the quality, the efficacy, and the safety for a novel nanomedicine to be approved. In that sense, this paper aimed (a) to prepare CUR-loaded polyethylene glycol-poly(ε-caprolactone) nanocapsules; (b) to validate an analytical method by high performance liquid chromatography (HPLC) for quantifying CUR in these nanoformulations; (c) to evaluate the physicochemical stability of these formulations; and to investigate their cytotoxicity on NIH-3T3 mouse fibroblast cells. The HPLC method was specific to CUR in the loaded nanocapsules, linear (r = 0.9994) in a range of 10.0 to 90.0 µg.mL-1 with limits of detection and quantification of 0.160 and 0.480 µg.mL-1, respectively. Precision was demonstrated by a relative standard deviation lower than 5%. Suitable accuracy (102.37 ± 0.92%) was obtained. Values of pH, particle size, polydispersity index, and zeta potential presented no statistical difference (p > 0.05) for CUR-loaded nanoparticles. No cytotoxicity was observed against NIH-3T3 mouse embryo fibroblast cell line using both the tetrazolium salt and sulforhodamine B assays. In conclusion, a simple and inexpensive HPLC method was validated for the CUR quantification in the suspensions of nanocapsules. The obtained polymeric nanocapsules containing CUR showed suitable results for all the performed assays and can be further investigated as a feasible novel approach for cancer treatment.


Asunto(s)
Animales , Ratones , Curcumina/farmacología , Células Madre Embrionarias/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Pruebas de Toxicidad , Nanotecnología , Células 3T3 NIH , Embrión de Mamíferos/citología , Nanocápsulas
5.
Acta Physiologica Sinica ; (6): 651-659, 2020.
Artículo en Inglés | WPRIM | ID: wpr-878210

RESUMEN

The study aims to investigate the effects of cardiac fibroblast (CF) paracrine factors on murine embryonic stem cells (ESCs). Conditioned mediums from either neonatal cardiac fibroblasts (ConM-NCF) or adult cardiac fibroblasts (ConM-ACF) were diluted by 1:50 and 1:5, respectively, to investigate whether these conditioned mediums impact murine ESCs distinctly with RT-real time PCR techniques, cell proliferation essay, ELISA and by counting percentage of beating embryoid bodies (EBs) during ESCs differentiation. The data showed that the paracrine ability of CFs changed dramatically during development, in which interleukin 6 (IL6) increased with maturation. ConM-NCF 1:50 and ConM-NCF 1:5 had opposite effects on the pluripotent markers, although they both reduced mouse ESC proliferation. ConM-ACF 1:50 promoted ESCs pluripotent markers and proliferation, while ConM-ACF 1:5 exerted negative effects. All CF-derived conditioned mediums inhibited cardiac differentiation, but with distinguishable features: ConM-NCF 1:50 slightly decreased the early cardiac differentiation without altering the maturation tendency or cardiac specific markers in EBs at differentiation of day 17; ConM-ACF 1:50 had more significant inhibitory effects on early cardiac differentiation than ConM-NCF 1:50 and impeded cardiac maturation with upregulation of cardiac specific markers. In addition, IL6 neutralization antibody attenuated positive effect of ConM-ACF 1:50 on ESCs proliferation, but had no effects on ConM-NCF 1:50. Long-term IL6 neutralization reduced the percentage of beating EBs at early developmental stage, but did not alter the late cardiac differentiation. Taken together, both the quality and quantity of factors and cytokines secreted by CFs are critical for the ESC fate. IL6 could be a favorable cytokine for ESC pluripotency and the early cardiac differentiation.


Asunto(s)
Animales , Ratones , Células Madre Embrionarias , Fibroblastos , Corazón , Células Madre Embrionarias de Ratones , Comunicación Paracrina
6.
International Journal of Stem Cells ; : 218-226, 2019.
Artículo en Inglés | WPRIM | ID: wpr-764080

RESUMEN

Wharton's jelly mesenchymal stem cells (WJ-MSCs) are a class of stem cells with high differentiative potential, an immuno-privileged status and easy access for collection, which raise no legal or ethical issues. WJ-MSCs exhibit several features of embryonic stem cells, both in the phenotypic and genetic aspects, with only a few differences, such as a shorter doubling time and a more extensive ex vivo expansion capacity. WJ-MSCs have immunomodulatory properties, involving both innate and adaptive immune responses. This review focuses on the role of WJ-MSCs in the management of graft-versus-host disease (GvHD), a life-threatening complication of the allogenic transplantation of hematopoietic stem cells. Different studies documented the beneficial effect of the infusion of WJ-MSCs, even when not fully HLA identical, in patients with severe GvHD, refractory to standard treatment. Finally, we summarized current ongoing clinical trials with WJ-MSCs and their potential in regenerative medicine.


Asunto(s)
Humanos , Células Madre Embrionarias , Ética , Enfermedad Injerto contra Huésped , Células Madre Hematopoyéticas , Inmunomodulación , Células Madre Mesenquimatosas , Medicina Regenerativa , Células Madre , Cordón Umbilical , Gelatina de Wharton
7.
International Journal of Stem Cells ; : 31-42, 2019.
Artículo en Inglés | WPRIM | ID: wpr-764063

RESUMEN

BACKGROUND AND OBJECTIVES: Genomic imprinting modulates growth and development in mammals and is associated with genetic disorders. Although uniparental embryonic stem cells have been used to study genomic imprinting, there is an ethical issue associated with the destruction of human embryos. In this study, to investigate the genomic imprinting status in human neurodevelopment, we used human uniparental induced pluripotent stem cells (iPSCs) that possessed only maternal alleles and differentiated into neural cell lineages. METHODS: Human somatic iPSCs (hSiPSCs) and human parthenogenetic iPSCs (hPgiPSCs) were differentiated into neural stem cells (NSCs) and named hSi-NSCs and hPgi-NSCs respectively. DNA methylation and gene expression of imprinted genes related neurodevelopment was analyzed during reprogramming and neural lineage differentiation. RESULTS: The DNA methylation and expression of imprinted genes were altered or maintained after differentiation into NSCs. The imprinting status in NSCs were maintained after terminal differentiation into neurons and astrocytes. In contrast, gene expression was differentially presented in a cell type-specific manner. CONCLUSIONS: This study suggests that genomic imprinting should be determined in each neural cell type because the genomic imprinting status can differ in a cell type-specific manner. In addition, the in vitro model established in this study would be useful for verifying the epigenetic alteration of imprinted genes which can be differentially changed during neurodevelopment in human and for screening novel imprinted genes related to neurodevelopment. Moreover, the confirmed genomic imprinting status could be used to find out an abnormal genomic imprinting status of imprinted genes related with neurogenetic disorders according to uniparental genotypes.


Asunto(s)
Humanos , Alelos , Astrocitos , Linaje de la Célula , Metilación de ADN , Células Madre Embrionarias , Estructuras Embrionarias , Epigenómica , Ética , Expresión Génica , Impresión Genómica , Genotipo , Crecimiento y Desarrollo , Técnicas In Vitro , Células Madre Pluripotentes Inducidas , Mamíferos , Tamizaje Masivo , Células-Madre Neurales , Neuronas
8.
Tissue Engineering and Regenerative Medicine ; (6): 107-118, 2019.
Artículo en Inglés | WPRIM | ID: wpr-761899

RESUMEN

BACKGROUND: Liver disease is one of the top causes of death globally. Although liver transplantation is a very effective treatment strategy, the shortage of available donor organs, waiting list mortality, and high costs of surgery remain huge problems. Stem cells are undifferentiated cells that can differentiate into a variety of cell types. Scientists are exploring the possibilities of generating hepatocytes from stem cells as an alternative for the treatment of liver diseases. METHODS: In this review, we summarized the updated researches in the field of stem cell-based therapies for liver diseases as well as the current challenges and future expectations for a successful cell-based liver therapy. RESULTS: Several cell types have been investigated for liver regeneration, such as embryonic stem cells, induced pluripotent stem cells, liver stem cells, mesenchymal stem cells, and hematopoietic stem cells. In vitro and in vivo studies have demonstrated that stem cells are promising cell sources for the liver regeneration. CONCLUSION: Stem cell-based therapy could be a promising therapeutic method for patients with end-stage liver disease, which may alleviate the need for liver transplantation in the future.


Asunto(s)
Humanos , Causas de Muerte , Células Madre Embrionarias , Células Madre Hematopoyéticas , Hepatocitos , Técnicas In Vitro , Células Madre Pluripotentes Inducidas , Hepatopatías , Regeneración Hepática , Trasplante de Hígado , Hígado , Células Madre Mesenquimatosas , Métodos , Mortalidad , Células Madre , Donantes de Tejidos , Listas de Espera
9.
The Korean Journal of Pain ; : 245-255, 2019.
Artículo en Inglés | WPRIM | ID: wpr-761715

RESUMEN

Stem cells are attracting attention as a key element in future medicine, satisfying the desire to live a healthier life with the possibility that they can regenerate tissue damaged or degenerated by disease or aging. Stem cells are defined as undifferentiated cells that have the ability to replicate and differentiate themselves into various tissues cells. Stem cells, commonly encountered in clinical or preclinical stages, are largely classified into embryonic, adult, and induced pluripotent stem cells. Recently, stem cell transplantation has been frequently applied to the treatment of pain as an alternative or promising approach for the treatment of severe osteoarthritis, neuropathic pain, and intractable musculoskeletal pain which do not respond to conventional medicine. The main idea of applying stem cells to neuropathic pain is based on the ability of stem cells to release neurotrophic factors, along with providing a cellular source for replacing the injured neural cells, making them ideal candidates for modulating and possibly reversing intractable neuropathic pain. Even though various differentiation capacities of stem cells are reported, there is not enough knowledge and technique to control the differentiation into desired tissues in vivo. Even though the use of stem cells is still in the very early stages of clinical use and raises complicated ethical problems, the future of stem cells therapies is very bright with the help of accumulating evidence and technology.


Asunto(s)
Adulto , Humanos , Células Madre Adultas , Envejecimiento , Diferenciación Celular , Células Madre Embrionarias , Células Madre Pluripotentes Inducidas , Dolor Musculoesquelético , Factores de Crecimiento Nervioso , Neuralgia , Osteoartritis , Trasplante de Células Madre , Células Madre
10.
Journal of Experimental Hematology ; (6): 606-612, 2019.
Artículo en Chino | WPRIM | ID: wpr-771912

RESUMEN

OBJECTIVE@#To establish the STO cell lines expressing green fluorescent protein (GFP) and mouse leukemia inhibitory factor (LIF) , and try to culture the mouse embryonic stem cells (mESCs) by using the established STO-GFP-mLIF cells as the feeder layer.@*METHODS@#The lentiviral particles containing GFP and mLIF and puromycin-resistance gene were constructed and transduced into STO cell lines. The cell lines stably expressing GFP and mLIF genes were screened out. The expression level of the inserted exogenous LIF gene was tested by Western blot and ELISA. The STO-GFP-mLIF cells were treated with different concentrations of mitomycin C (5, 10, 15, 20 µg/ml) for different time (1.5, 2.5, 3, 3.5 hours) to prepare feeder layers and the cell proliferation level on feeder layer was observed. Mouse embryonic stem cells were cultured on mitomycin C-treated feeder layer and the growth of cell colonies was observed.@*RESULTS@#The expression level of LIF protein in STO-GFP-mLIF cells was up-regulated, as compared with STO cells (P<0.05). It was confirmed that the optimal concentration and time for inhibiting the proliferetion of STO-GFP-mLIF cells by mitomycin C were 10 µg/ml and 3 hours respectively. The observation also found that the embryonic stem cells could develop into typic "birdnest" shaped stem cell colony on mitomycin C-treated feeder layer.@*CONCLUSION@#The stable STO cell lines effectively expressing green fluorescent protein and mouse leukemia inhibitory factor have been established successfully, which can maintain the undifferentiated state of mouse embryonic stem cells.


Asunto(s)
Animales , Ratones , Diferenciación Celular , Línea Celular , Separación Celular , Células Madre Embrionarias , Células Nutrientes , Proteínas Fluorescentes Verdes , Factor Inhibidor de Leucemia
11.
Chinese Journal of Biotechnology ; (12): 910-918, 2019.
Artículo en Chino | WPRIM | ID: wpr-771835

RESUMEN

Parthenogenetic embryonic stem cells (pESCs) derived from bi-maternal genomes do not have competency of tetraploid complementation, due to lacking of paternal imprinting genes. To make pESCs possess fully development potentials and similar pluripotency to zygote-derived ESCs, we knocked out one allelic gene of the two essential maternal imprinting genes (H19 and IG) in their differentially methylated regions (DMR) via CRISPR/Cas9 system and obtained double knock out (DKO) pESCs. Maternal pESCs had similar morphology, expression levels of pluripotent makers and in vitro neural differentiation potentials to zygotes-derived ESCs. Besides that, DKO pESCs could contribute to full-term fetuses through tetraploid complementation, proving that they held fully development potentials. Derivation of DKO pESCs provided a type of major histocompatibility complex (MHC) matched pluripotent stem cells, which would benefit research in regenerative medicine.


Asunto(s)
Animales , Ratones , Células Madre Embrionarias , Técnicas de Inactivación de Genes , Impresión Genómica , Partenogénesis , Células Madre Pluripotentes , Medicina Regenerativa , Tetraploidía
12.
Chinese Journal of Biotechnology ; (12): 784-794, 2019.
Artículo en Chino | WPRIM | ID: wpr-771331

RESUMEN

The establishment and development of gene knockout mice have provided powerful support for the study of gene function and the treatment of human diseases. Gene targeting and gene trap are two techniques for generating gene knockout mice from embryonic stem cells. Gene targeting replaces endogenous knockout gene by homologous recombination. There are two ways to knock out target genes: promoter trap and polyA trap. In recent years, many new gene knockout techniques have been developed, including Cre/loxP system, CRISP/Cas9 system, latest ZFN technology and TALEN technology. This article focuses on the several new knockout mouse techniques.


Asunto(s)
Animales , Humanos , Ratones , Modelos Animales de Enfermedad , Células Madre Embrionarias , Técnicas de Inactivación de Genes , Marcación de Gen , Recombinación Homóloga , Ratones Noqueados
13.
International Journal of Stem Cells ; : 484-496, 2019.
Artículo en Inglés | WPRIM | ID: wpr-785825

RESUMEN

Previously, the majority of human embryonic stem cells and human induced pluripotent stem cells have been derived on feeder layers and chemically undefined medium. Those media components related to feeder cells, or animal products, often greatly affect the consistency of the cell culture. There are clear advantages of a defined, xeno-free, and feeder-free culture system for human pluripotent stem cells (hPSCs) cultures, since consistency in the formulations prevents lot-to-lot variability. Eliminating all non-human components reduces health risks for downstream applications, and those environments reduce potential immunological reactions from stem cells. Therefore, development of feeder-free hPSCs culture systems has been an important focus of hPSCs research. Recently, researchers have established a variety of culture systems in a defined combination, xeno-free matrix and medium that supports the growth and differentiation of hPSCs. Here we described detailed hPSCs culture methods under feeder-free and chemically defined conditions using vitronetin and TeSR-E8 medium including supplement bioactive lysophospholipid for promoting hPSCs proliferation and maintaining stemness.


Asunto(s)
Animales , Humanos , Técnicas de Cultivo de Célula , Células Madre Embrionarias , Matriz Extracelular , Células Nutrientes , Células Madre Embrionarias Humanas , Células Madre Pluripotentes Inducidas , Células Madre Pluripotentes , Células Madre
14.
Biomolecules & Therapeutics ; : 15-24, 2019.
Artículo en Inglés | WPRIM | ID: wpr-719412

RESUMEN

Neural stem cells (NSCs) can proliferate and differentiate into multiple cell types that constitute the nervous system. NSCs can be derived from developing fetuses, embryonic stem cells, or induced pluripotent stem cells. NSCs provide a good platform to screen drugs for neurodegenerative diseases and also have potential applications in regenerative medicine. Natural products have long been used as compounds to develop new drugs. In this review, natural products that control NSC fate and induce their differentiation into neurons or glia are discussed. These phytochemicals enable promising advances to be made in the treatment of neurodegenerative diseases.


Asunto(s)
Productos Biológicos , Células Madre Embrionarias , Feto , Células Madre Pluripotentes Inducidas , Sistema Nervioso , Células-Madre Neurales , Enfermedades Neurodegenerativas , Neurogénesis , Neuroglía , Neuronas , Neuroprotección , Fitoquímicos , Medicina Regenerativa
15.
Tissue Engineering and Regenerative Medicine ; (6): 93-102, 2019.
Artículo en Inglés | WPRIM | ID: wpr-742381

RESUMEN

BACKGROUND: Mesenchymal stem cells (MSCs) can be used for a wide range of therapeutic applications because of not only their differentiation potential but also their ability to secrete bioactive factors. Recently, several studies have suggested the use of human embryonic stem cell-derived MSCs (hE-MSCs) as an alternative for regenerative cellular therapy due to mass production of MSCs from a single donor. METHODS: We generated hE-MSCs from embryonic stem cell lines, SNUhES3, and analyzed immune properties of these cells. Also, we evaluated the in-vivo therapeutic potential of hE-MSCs in immune-mediated inflammatory skin disease. RESULTS: The cell showed the suppression of immunity associated with allogenic peripheral blood mononuclear cells in mixed lymphocyte response assay. We also detected that cytokines and growth factor related to the immune response were secreted from these cells. To assessed the in-vivo therapeutic potential of hE-MSCs in immune-mediated inflammatory skin disease, we used imiquimod (IMQ)-induced skin psoriasis mouse model. The score of clinical skin was significantly reduced in the hE-MSCs treated group compared with control IMQ group. In histological analysis, the IMQ-induced epidermal thickness was significantly decreased by hE-MSCs treatment. It was correlated with splenomegaly induced by IMQ which was also improved in the hE-MSCs. Moreover, IMQ-induced inflammatory cytokines; Th1 cytokines (TNF-α, IFN-α, IFN-γ,and IL-27) and Th17 cytokines (IL-17A and IL-23), in the serum and skin showed marked inhibition by hEMSCs. CONCLUSION: These results suggested that hE-MSCs have a potency of immune modulation in psoriasis, which might be the key factor for the improved psoriasis.


Asunto(s)
Animales , Humanos , Ratones , Citocinas , Células Madre Embrionarias , Linfocitos , Células Madre Mesenquimatosas , Psoriasis , Enfermedades de la Piel , Piel , Esplenomegalia , Donantes de Tejidos
16.
The World Journal of Men's Health ; : 166-174, 2019.
Artículo en Inglés | WPRIM | ID: wpr-742361

RESUMEN

The survival rates of boys and men with cancer have increased due to advances in cancer treatments; however, maintenance of quality of life, including fertility preservation, remains a major issue. Fertile male patients who receive radiation and/or chemotherapy face temporary, long-term, or permanent gonadal damage, particularly with exposure to alkylating agents and whole-body irradiation, which sometimes induce critical germ cell damage. These cytotoxic treatments have a significant impact on a patient's ability to have their own biological offspring, which is of particular concern to cancer patients of reproductive age. Therefore, various strategies are needed in order to preserve male fertility. Sperm cryopreservation is an effective method for preserving spermatozoa. Advances have also been achieved in pre-pubertal germ cell storage and research to generate differentiated male germ cells from various types of stem cells, including embryonic stem cells, induced pluripotent stem cells, and spermatogonial stem cells. These approaches offer hope to many patients in whom germ cell loss is associated with sterility, but are still experimental and preliminary. This review examines the current understanding of the effects of chemotherapy and radiation on male fertility.


Asunto(s)
Humanos , Masculino , Alquilantes , Criopreservación , Quimioterapia , Células Madre Embrionarias , Fertilidad , Preservación de la Fertilidad , Células Germinativas , Gónadas , Esperanza , Células Madre Pluripotentes Inducidas , Infertilidad , Infertilidad Masculina , Métodos , Calidad de Vida , Radioterapia , Espermatogénesis , Espermatozoides , Células Madre , Tasa de Supervivencia , Irradiación Corporal Total
17.
J. venom. anim. toxins incl. trop. dis ; 24: 11, 2018. tab, graf, ilus
Artículo en Inglés | LILACS | ID: biblio-894174

RESUMEN

Peripheral nerve injury is a worldwide clinical problem, and the preferred surgical method for treating it is the end-to-end neurorrhaphy. When it is not possible due to a large nerve gap, autologous nerve grafting is used. However, these surgical techniques result in nerve regeneration at highly variable degrees. It is thus very important to seek complementary techniques to improve motor and sensory recovery. One promising approach could be cell therapy. Transplantation therapy with human embryonic stem cells (hESCs) is appealing because these cells are pluripotent and can differentiate into specialized cell types and have self-renewal ability. Therefore, the main objective of this study was to find conditions under which functional recovery is improved after sciatic nerve neurorrhaphy. We assumed that hESC, either alone or in combination with heterologous fibrin sealant scaffold, could be used to support regeneration in a mouse model of sciatic nerve injury and repair via autografting with end-to-end neurorrhaphy. Methods Five millimeters of the sciatic nerve of C57BL/6 J mice were transected off and rotated 180 degrees to simulate an injury, and then stumps were sutured. Next, we applied heterologous fibrin sealant and/or human embryonic stem cells genetically altered to overexpress fibroblast growth factor 2 (FGF2) at the site of the injury. The study was designed to include six experimental groups comprising neurorrhaphy (N), neurorrhaphy + heterologous fibrin sealant (N + F), neurorrhaphy + heterologous fibrin sealant + doxycycline (N + F + D), neurorrhaphy + heterologous fibrin sealant + wild-type hESC (N + F + W), neurorrhaphy + heterologous fibrin sealant + hESC off (N + F +T), and neurorrhaphy + heterologous fibrin sealant + hESC on via doxycycline (N + F + D + T). We evaluated the recovery rate using Catwalk and von Frey functional recovery tests, as well as immunohistochemistry analysis. Results The experiments indicated that sensory function improved when transgenic hESCs were used. The regeneration of sensory fibers indeed led to increased reflexes, upon stimulation of the paw ipsilateral to the lesion, as seen by von-Frey evaluation, which was supported by immunohistochemistry. Conclusions Overall, the present data demonstrated that transgenic embryonic stem cells, engineered to overexpress FGF-2 in an inducible fashion, could be employed to support regeneration aiming at the recovery of both motor and sensory functions.(AU)


Asunto(s)
Animales , Masculino , Ratas , Nervio Ciático/trasplante , Trasplante Heterólogo/rehabilitación , Adhesivo de Tejido de Fibrina , Células Madre Embrionarias , Regeneración Nerviosa , Ratones Endogámicos C57BL
18.
International Journal of Stem Cells ; : 242-247, 2018.
Artículo en Inglés | WPRIM | ID: wpr-739922

RESUMEN

Ubiquitination of proteins plays an essential role in various cellular processes, including protein degradation, DNA repair, and cell signaling pathways. Previous studies have shown that protein ubiquitination is implicated in regulating pluripotency as well as fate determination of stem cells. To identify how protein ubiquitination affects differentiation of embryonic stem cells, we analyzed microarray data, which are available in the public domain, of E3 ligases and deubiquitinases whose levels changed during stem cell differentiation. Expression of pja2, a member of the RING-type E3 ligase family, was up-regulated during differentiation of stem cells. Wnt/β-catenin signaling is one of the most important signaling pathways for regulation of the self-renewal and differentiation of embryonic stem cells. Pja2 was shown to bind to TCF/LEF1, which are transcriptional factors for Wnt/β-catenin signaling, and regulate protein levels by ubiquitination, leading to down-regulation of Wnt signaling activity. Based on these results, we suggest that E3 ligase Pja2 regulates stem cell differentiation by controlling the level of TCF/LEF1 by ubiquitination.


Asunto(s)
Humanos , Reparación del ADN , Regulación hacia Abajo , Células Madre Embrionarias , Ligasas , Proteolisis , Sector Público , Células Madre , Ubiquitina , Ubiquitina-Proteína Ligasas , Proteasas Ubiquitina-Específicas , Ubiquitinación
19.
International Journal of Stem Cells ; : 121-130, 2018.
Artículo en Inglés | WPRIM | ID: wpr-739914

RESUMEN

BACKGROUND AND OBJECTIVE: The potency of tissue resident stem cells is regulated primarily by inputs from the local microenvironment. Isolation of stem cells through enzymatic digestion of tissue may affect epigenetic regulation of cell fate and performance. Here we employ a non-enzymatic method to harvest and investigate tissue resident stem cells from the adult porcine pulmonary valve. METHODS AND RESULTS: The presence of c-Kit+ stem cells within the valve tissue was confirmed by immunohistochemistry. An in vitro culture of minced valve leaflets was developed under the standard conditions (37°C with 5% CO2). The viability of the cellular outgrowths was evaluated over the subsequent 12 weeks. Under this culture condition, we identified a population of non-adherent c-Kit+ cells and multiple cellular structures mimicking the phenotype of embryonic stem cells at different stages of development. Formation of multinucleated cells through cell fusion provided an active niche area for homing and interaction of the non-adherent c-Kit+ cells. Expression of pluripotency markers Oct-4 and Nanog was detected in the newly formed multinucleated cells but not in mature colonies. Partial cell fusion was shown by fluorescent live-cell tracking, which confirmed intercellular molecular exchange between donor and recipient cells, resulting in altered cytoplasmic protein expression by the recipient cell. CONCLUSIONS: These results suggest a role for the microenvironment in decrypting the potential of the valve somatic stem cells in vitro. In addition, our data provide evidence for cell fusion, which may play a critical role in reversing somatic cell fate and spontaneous cellular reprogramming.


Asunto(s)
Adulto , Humanos , Fusión Celular , Microambiente Celular , Reprogramación Celular , Estructuras Celulares , Citoplasma , Digestión , Células Madre Embrionarias , Epigenómica , Válvulas Cardíacas , Inmunohistoquímica , Técnicas In Vitro , Métodos , Fenotipo , Válvula Pulmonar , Células Madre , Donantes de Tejidos
20.
Protein & Cell ; (12): 945-965, 2018.
Artículo en Inglés | WPRIM | ID: wpr-757939

RESUMEN

Vascular cell functionality is critical to blood vessel homeostasis. Constitutive NF-κB activation in vascular cells results in chronic vascular inflammation, leading to various cardiovascular diseases. However, how NF-κB regulates human blood vessel homeostasis remains largely elusive. Here, using CRISPR/Cas9-mediated gene editing, we generated RelA knockout human embryonic stem cells (hESCs) and differentiated them into various vascular cell derivatives to study how NF-κB modulates human vascular cells under basal and inflammatory conditions. Multi-dimensional phenotypic assessments and transcriptomic analyses revealed that RelA deficiency affected vascular cells via modulating inflammation, survival, vasculogenesis, cell differentiation and extracellular matrix organization in a cell type-specific manner under basal condition, and that RelA protected vascular cells against apoptosis and modulated vascular inflammatory response upon tumor necrosis factor α (TNFα) stimulation. Lastly, further evaluation of gene expression patterns in IκBα knockout vascular cells demonstrated that IκBα acted largely independent of RelA signaling. Taken together, our data reveal a protective role of NF-κB/RelA in modulating human blood vessel homeostasis and map the human vascular transcriptomic landscapes for the discovery of novel therapeutic targets.


Asunto(s)
Humanos , Vasos Sanguíneos , Biología Celular , Metabolismo , Sistemas CRISPR-Cas , Células Madre Embrionarias , Biología Celular , Técnicas de Inactivación de Genes , Homeostasis , FN-kappa B , Metabolismo , Factor de Transcripción ReIA , Metabolismo
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