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1.
Chinese Journal of Hepatology ; (12): 244-248, 2022.
Article in Chinese | WPRIM | ID: wpr-935935

ABSTRACT

Liver is one of the most important organs in the human body. Liver diseases are also a major threat to human health and longevity. Hepatic decompensation treatment is quite difficult due to multiple reasons. Extracorporeal liver support devices are unable to solve this problem, and there is a severe shortage of orthotopic liver transplant donors. Study of pluripotent stem cell-derived hepatocytes and organoids can determine not only hepatocyte fate, but also liver development, regeneration mechanisms, and pathophysiology. Furthermore, it can be used for drug screening in order to provide a stable source of functional hepatocytes for future transplantation therapy. Culture of pluripotent stem cell-derived hepatocytes and organoids has a self-organizing process similar to liver development, i.e., starting with changes in several key factors, and eventually forming functionally complex cells/organs. This paper introduces the main methods and progress of pluripotent stem cell-derived hepatocytes and organoids, with hope to provide clues for future research.


Subject(s)
Cell Differentiation , Hepatocytes , Humans , Induced Pluripotent Stem Cells , Liver , Organoids , Pluripotent Stem Cells
2.
Protein & Cell ; (12): 490-512, 2022.
Article in English | WPRIM | ID: wpr-939864

ABSTRACT

LIN28 is an RNA binding protein with important roles in early embryo development, stem cell differentiation/reprogramming, tumorigenesis and metabolism. Previous studies have focused mainly on its role in the cytosol where it interacts with Let-7 microRNA precursors or mRNAs, and few have addressed LIN28's role within the nucleus. Here, we show that LIN28 displays dynamic temporal and spatial expression during murine embryo development. Maternal LIN28 expression drops upon exit from the 2-cell stage, and zygotic LIN28 protein is induced at the forming nucleolus during 4-cell to blastocyst stage development, to become dominantly expressed in the cytosol after implantation. In cultured pluripotent stem cells (PSCs), loss of LIN28 led to nucleolar stress and activation of a 2-cell/4-cell-like transcriptional program characterized by the expression of endogenous retrovirus genes. Mechanistically, LIN28 binds to small nucleolar RNAs and rRNA to maintain nucleolar integrity, and its loss leads to nucleolar phase separation defects, ribosomal stress and activation of P53 which in turn binds to and activates 2C transcription factor Dux. LIN28 also resides in a complex containing the nucleolar factor Nucleolin (NCL) and the transcriptional repressor TRIM28, and LIN28 loss leads to reduced occupancy of the NCL/TRIM28 complex on the Dux and rDNA loci, and thus de-repressed Dux and reduced rRNA expression. Lin28 knockout cells with nucleolar stress are more likely to assume a slowly cycling, translationally inert and anabolically inactive state, which is a part of previously unappreciated 2C-like transcriptional program. These findings elucidate novel roles for nucleolar LIN28 in PSCs, and a new mechanism linking 2C program and nucleolar functions in PSCs and early embryo development.


Subject(s)
Animals , Cell Differentiation , Embryo, Mammalian/metabolism , Embryonic Development , Mice , Pluripotent Stem Cells/metabolism , RNA, Messenger/genetics , RNA, Ribosomal , RNA-Binding Proteins/metabolism , Transcription Factors/metabolism , Zygote/metabolism
3.
Article in English | WPRIM | ID: wpr-939827

ABSTRACT

Organoid models are used to study kidney physiology, such as the assessment of nephrotoxicity and underlying disease processes. Personalized human pluripotent stem cell-derived kidney organoids are ideal models for compound toxicity studies, but there is a need to accelerate basic and translational research in the field. Here, we developed an automated continuous imaging setup with the "read-on-ski" law of control to maximize temporal resolution with minimum culture plate vibration. High-accuracy performance was achieved: organoid screening and imaging were performed at a spatial resolution of 1.1 μm for the entire multi-well plate under 3 min. We used the in-house developed multi-well spinning device and cisplatin-induced nephrotoxicity model to evaluate the toxicity in kidney organoids using this system. The acquired images were processed via machine learning-based classification and segmentation algorithms, and the toxicity in kidney organoids was determined with 95% accuracy. The results obtained by the automated "read-on-ski" imaging device, combined with label-free and non-invasive algorithms for detection, were verified using conventional biological procedures. Taking advantage of the close-to-in vivo-kidney organoid model, this new development opens the door for further application of scaled-up screening using organoids in basic research and drug discovery.


Subject(s)
Humans , Kidney , Organoids , Pluripotent Stem Cells
4.
Arq. bras. oftalmol ; 83(2): 160-167, Mar.-Apr. 2020. tab, graf
Article in English | LILACS | ID: biblio-1088965

ABSTRACT

ABSTRACT Degenerative retinal diseases such as retinitis pigmentosa, Stargardt's macular dystrophy, and age-related macular degeneration are characterized by irreversible loss of vision due to direct or indirect photoreceptor damage. No effective treatments exist, but stem cell studies have shown promising results. Our aim with this review was to describe the types of stem cells that are under study, their effects, and the main clinical trials involving them.


RESUMO As doenças degenerativas da retina, como retinose pigmentar, distrofia macular de Stargardt e degeneração macular relaciona à idade, são caracterizadas por perda irre versível da visão devido a danos diretos ou indiretos aos fotorreceptores. Não existem tratamentos eficazes, porém os estudos com células-tronco mostraram resultados promissores. Nosso objetivo com esta revisão foi descrever os tipos de células-tronco em estudo, seus efeitos e os principais ensaios clínicos que as envolvem.


Subject(s)
Humans , Retinal Degeneration/therapy , Pluripotent Stem Cells/transplantation , Stem Cell Transplantation/methods , Retina/cytology , Clinical Trials as Topic , Treatment Outcome
6.
Article in English | WPRIM | ID: wpr-785825

ABSTRACT

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.


Subject(s)
Animals , Cell Culture Techniques , Embryonic Stem Cells , Extracellular Matrix , Feeder Cells , Human Embryonic Stem Cells , Humans , Induced Pluripotent Stem Cells , Pluripotent Stem Cells , Stem Cells
7.
Article in English | WPRIM | ID: wpr-764078

ABSTRACT

BACKGROUND AND OBJECTIVES: Proficient differentiation of human pluripotent stem cells (hPSCs) into specific lineages is required for applications in regenerative medicine. A growing amount of evidences had implicated hormones and hormone-like molecules as critical regulators of proliferation and lineage specification during in vivo development. Therefore, a deeper understanding of the hormones and hormone-like molecules involved in cell fate decisions is critical for efficient and controlled differentiation of hPSCs into specific lineages. Thus, we functionally and quantitatively compared the effects of diverse hormones (estradiol 17-β (E2), progesterone (P4), and dexamethasone (DM)) and a hormone-like molecule (retinoic acid (RA)) on the regulation of hematopoietic and neural lineage specification. METHODS AND RESULTS: We used 10 nM E2, 3 μM P4, 10 nM DM, and 10 nM RA based on their functional in vivo developmental potential. The sex hormone E2 enhanced functional activity of hematopoietic progenitors compared to P4 and DM, whereas RA impaired hematopoietic differentiation. In addition, E2 increased CD34⁺CD45⁺ cells with progenitor functions, even in the CD43⁻ population, a well-known hemogenic marker. RA exhibited lineage-biased potential, preferentially committing hPSCs toward the neural lineage while restricting the hematopoietic fate decision. CONCLUSIONS: Our findings reveal unique cell fate potentials of E2 and RA treatment and provide valuable differentiation information that is essential for hPSC applications.


Subject(s)
Dexamethasone , Humans , Induced Pluripotent Stem Cells , Pluripotent Stem Cells , Progesterone , Regenerative Medicine , Tretinoin
8.
Experimental Neurobiology ; : 329-336, 2019.
Article in English | WPRIM | ID: wpr-763771

ABSTRACT

Alzheimer's Disease (AD) is a progressive neurodegenerative disease, which is pathologically defined by the accumulation of amyloid plaques and hyper-phosphorylated tau aggregates in the brain. Mitochondrial dysfunction is also a prominent feature in AD, and the extracellular Aβ and phosphorylated tau result in the impaired mitochondrial dynamics. In this study, we generated an induced pluripotent stem cell (iPSC) line from an AD patient with amyloid precursor protein (APP) mutation (Val715Met; APP-V715M) for the first time. We demonstrated that both extracellular and intracellular levels of Aβ were dramatically increased in the APP-V715M iPSC-derived neurons. Furthermore, the APP-V715M iPSC-derived neurons exhibited high expression levels of phosphorylated tau (AT8), which was also detected in the soma and neurites by immunocytochemistry. We next investigated mitochondrial dynamics in the iPSC-derived neurons using Mito-tracker, which showed a significant decrease of anterograde and retrograde velocity in the APP-V715M iPSC-derived neurons. We also found that as the Aβ and tau pathology accumulates, fusion-related protein Mfn1 was decreased, whereas fission-related protein DRP1 was increased in the APP-V715M iPSC-derived neurons, compared with the control group. Taken together, we established the first iPSC line derived from an AD patient carrying APP-V715M mutation and showed that this iPSC-derived neurons exhibited typical AD pathological features, including a distinct mitochondrial dysfunction.


Subject(s)
Alzheimer Disease , Amyloid , Brain , Carisoprodol , Humans , Immunohistochemistry , Mitochondrial Dynamics , Neurites , Neurodegenerative Diseases , Neurons , Pathology , Plaque, Amyloid , Pluripotent Stem Cells
9.
Chinese Journal of Biotechnology ; (12): 910-918, 2019.
Article in Chinese | WPRIM | ID: wpr-771835

ABSTRACT

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.


Subject(s)
Animals , Embryonic Stem Cells , Gene Knockout Techniques , Genomic Imprinting , Mice , Parthenogenesis , Pluripotent Stem Cells , Regenerative Medicine , Tetraploidy
10.
Int. j. morphol ; 36(1): 48-53, Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-893185

ABSTRACT

SUMMARY: Doxorubicin is a drug that used by a majority in the treatment of carcinomas. The most obvious known side effect is cardiomyopathy. Many studies have been carried out to eliminate side effects of the doxorubicin, and stem cell studies have been added in recent years. In this study, it was aimed to investigate fetal-derived mesenchymal stem cells (F-MSCs) treatment of doxorubicininduced cardiomyopathy by morphological methods. A total of 24 rats which were divided into three separate groups (Control, sham, treatment), each consisting of 8 male rats were used. In sham and treatment group, Adriamycin was administered in a single dose by tail injection to perform cardiotoxicity. In the treatment group, F-MSCs were intra-peritoneally administrated. Then, rats were euthanized and their hearts were photographed at the level of papillary muscle. and thickness, diameters and surface area levels were measured. Left ventricular mass (LVM) and left ventricular mass index (LVMI) were calculated after measurement. The sham group, LVM and LVMI levels were found to significantly lower (p<0.05) than control and treatment group. In the one hand, LVMI levels of rats in treatment group was statistically similar (p>0.05) to control group. Similarly, LVM levels of control and treatment groups were close to each other while this level of sham group was lower. It has been shown that F-MSC administrations in rats with doxorubicin-induced cardiomyopathy have adverse effect on LVM and LVMI values. In addition, the intra-peritoneal MSC administrations may be an alternative to other injection routes such as intra-venous and intra-cardiac administrations.


RESUMEN: La doxorrubicina es un medicamento usado ampliamente en el tratamiento de carcinomas. El efecto secundario más conocido es la miocardiopatía. Se han llevado a cabo muchos estudios para eliminar los efectos secundarios de la doxorrubicina, y en los últimos años se han agregado estudios con células madre. mediante métodos morfológicos, se intentó investigar el tratamiento de las células madre mesenquimales (F-MSCs) derivadas del feto, de la miocardiopatía inducida por doxorrubicina. Se utilizó un total de 24 ratas que se dividieron en tres grupos (control, simulación, tratamiento), cada uno de las cuales consistía en 8 ratas macho. En el tratamiento simulado y en el grupo tratamiento, se administró doxorrubicina en una dosis única mediante inyección en la cola de la rata para realizar cardiotoxicidad. En el grupo tratamiento, las FMSC se administraron intraperitonealmente. Luego, las ratas fueron sacrificadas y sus corazones fueron fotografiados a nivel de los músculos papilares, y se midieron los espesores, los diámetros y los niveles de área superficial. Después de las mediciones se calcularon la masa ventricular izquierda (MVI) y el índice de masa ventricular izquierda (IMVI). En el grupo simulado, los niveles de MVI y IMVI se encontraron significativamente inferiores (p <0.05) que en los grupos control y tratamiento. Por un lado, los niveles de IMVI de las ratas en el grupo de tratamiento fueron estadísticamente similares (p> 0,05) al grupo de control. De forma similar, los niveles de MVI de los grupos control y tratamiento se aproximaban uno al otro, mientras que este nivel era más bajo en el grupo simulado. Se ha demostrado que la administracion de F-MSC en ratas con miocardiopatía inducida por doxorrubicina tiene un efecto adverso sobre los valores de MVI y IMVI. Además, la administracion de MSC intraperitoneal puede ser una alternativa a otras rutas de inyección tal como las administración intravenosa e intracardíaca.


Subject(s)
Animals , Male , Rats , Cardiomyopathies/drug therapy , Heart Ventricles/drug effects , Pluripotent Stem Cells , Cardiomyopathies/chemically induced , Doxorubicin/toxicity , Heart Ventricles/pathology , Rats, Sprague-Dawley
11.
Braz. j. med. biol. res ; 51(5): e7183, 2018. graf
Article in English | LILACS | ID: biblio-889088

ABSTRACT

Human pluripotent stem cells (hPSCs)/OP9 coculture system is a widely used hematopoietic differentiation approach. The limited understanding of this process leads to its low efficiency. Thus, we used single-cell qPCR to reveal the gene expression profiles of individual CD34+ cells from different stages of differentiation. According to the dynamic gene expression of hematopoietic transcription factors, we overexpressed specific hematopoietic transcription factors (Gata2, Lmo2, Etv2, ERG, and SCL) at an early stage of hematopoietic differentiation. After overexpression, we generated more CD34+ cells with normal expression level of CD43 and CD31, which are used to define various hematopoietic progenitors. Furthermore, these CD34+ cells possessed normal differentiation potency in colony-forming unit assays and normal gene expression profiles. In this study, we demonstrated that single-cell qPCR can provide guidance for optimization of hematopoietic differentiation and transient overexpression of selected hematopoietic transcription factors can enhance hematopoietic differentiation.


Subject(s)
Humans , Hematopoietic Stem Cells/cytology , Cell Differentiation , Coculture Techniques/methods , Pluripotent Stem Cells/cytology , Phenotype , Gene Expression , Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Single-Cell Analysis/methods , Flow Cytometry
12.
Korean Circulation Journal ; : 974-988, 2018.
Article in English | WPRIM | ID: wpr-738662

ABSTRACT

Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), which are collectively called pluripotent stem cells (PSCs), have emerged as a promising source for regenerative medicine. Particularly, human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) have shown robust potential for regenerating injured heart. Over the past two decades, protocols to differentiate hPSCs into CMs at high efficiency have been developed, opening the door for clinical application. Studies further demonstrated therapeutic effects of hPSC-CMs in small and large animal models and the underlying mechanisms of cardiac repair. However, gaps remain in explanations of the therapeutic effects of engrafted hPSC-CMs. In addition, bioengineering technologies improved survival and therapeutic effects of hPSC-CMs in vivo. While most of the original concerns associated with the use of hPSCs have been addressed, several issues remain to be resolved such as immaturity of transplanted cells, lack of electrical integration leading to arrhythmogenic risk, and tumorigenicity. Cell therapy with hPSC-CMs has shown great potential for biological therapy of injured heart; however, more studies are needed to ensure the therapeutic effects, underlying mechanisms, and safety, before this technology can be applied clinically.


Subject(s)
Biocompatible Materials , Bioengineering , Biological Therapy , Cell- and Tissue-Based Therapy , Embryonic Stem Cells , Heart , Humans , Induced Pluripotent Stem Cells , Models, Animal , Myocytes, Cardiac , Pluripotent Stem Cells , Regeneration , Regenerative Medicine , Therapeutic Uses
13.
Experimental Neurobiology ; : 350-364, 2018.
Article in English | WPRIM | ID: wpr-717416

ABSTRACT

Disease modeling of Alzheimer's disease (AD) has been hampered by the lack of suitable cellular models while animal models are mainly based on the overexpression of AD-related genes which often results in an overemphasis of certain pathways and is also confounded by aging. In this study, we therefore developed and used induced pluripotent stem cell (iPSC) lines from a middle-aged AD patient with a known presenilin 1 (PSEN1) mutation (Glu120Lys; PS1-E120K) and as a control, an elderly normal subject. Using this approach, we demonstrated that the extracellular accumulation of Aβ was dramatically increased in PS1-E120K iPSC-derived neurons compared with the control iPSC line. PS1-E120K iPSC-derived neurons also exhibited high levels of phosphorylated tau, as well as mitochondrial abnormalities and defective autophagy. Given that the effect of aging is lost with iPSC generation, these abnormal cellular features are therefore indicative of PSEN1-associated AD pathogenesis rather than primary changes associated with aging. Taken together, this iPSC-based approach of AD modeling can now be used to better understand AD pathogenesis as well as a tool for drug discovery.


Subject(s)
Aged , Aging , Alzheimer Disease , Autophagy , Cerebellar Ataxia , Drug Discovery , Humans , Models, Animal , Neurons , Pluripotent Stem Cells , Presenilin-1 , Stem Cells
14.
Article in English | WPRIM | ID: wpr-716083

ABSTRACT

The establishment of protocols to differentiate kidney organoids from human pluripotent stem cells provides potential applications of kidney organoids in regenerative medicine. Modeling of renal diseases, drug screening, nephrotoxicity testing of compounds, and regenerative therapy are attractive applications. Although much progress still remains to be made in the development of kidney organoids, recent advances in clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated system 9 (Cas9) genome editing and three-dimensional bioprinting technologies have contributed to the application of kidney organoids in clinical fields. In this section, we review recent advances in the applications of kidney organoids to kidney disease modelling, drug screening, nephrotoxicity testing, and regenerative therapy.


Subject(s)
Bioprinting , Clustered Regularly Interspaced Short Palindromic Repeats , Drug Evaluation, Preclinical , Genome , Humans , Kidney Diseases , Kidney , Organoids , Pluripotent Stem Cells , Regenerative Medicine , Transplantation
15.
Protein & Cell ; (12): 717-728, 2018.
Article in English | WPRIM | ID: wpr-758019

ABSTRACT

It is not fully clear why there is a higher contribution of pluripotent stem cells (PSCs) to the chimera produced by injection of PSCs into 4-cell or 8-cell stage embryos compared with blastocyst injection. Here, we show that not only embryonic stem cells (ESCs) but also induced pluripotent stem cells (iPSCs) can generate F0 nearly 100% donor cell-derived mice by 4-cell stage embryo injection, and the approach has a "dose effect". Through an analysis of the PSC-secreted proteins, Activin A was found to impede epiblast (EPI) lineage development while promoting trophectoderm (TE) differentiation, resulting in replacement of the EPI lineage of host embryos with PSCs. Interestingly, the injection of ESCs into blastocysts cultured with Activin A (cultured from 4-cell stage to early blastocyst at E3.5) could increase the contribution of ESCs to the chimera. The results indicated that PSCs secrete protein Activin A to improve their EPI competency after injection into recipient embryos through influencing the development of mouse early embryos. This result is useful for optimizing the chimera production system and for a deep understanding of PSCs effects on early embryo development.


Subject(s)
Activins , Metabolism , Animals , Cells, Cultured , Embryonic Development , Germ Layers , Metabolism , Mice , Pluripotent Stem Cells , Cell Biology , Metabolism
16.
Article in English | WPRIM | ID: wpr-718790

ABSTRACT

BACKGROUND: Bone tissue engineering based on pluripotent stem cells (PSCs) is a new approach to deal with bone defects. Protocols have been developed to generate osteoblasts from PSCs. However, the low efficiency of this process is still an important issue that needs to be resolved. Many studies have aimed to improve efficiency, but developing accurate methods to determine efficacy is also critical. Studies using pluripotency to estimate efficacy are rare. Telomerase is highly associated with pluripotency. METHODS: We have described a quantitative method to measure telomerase activity, telomeric repeat elongation assay based on quartz crystal microbalance (QCM). To investigate whether this method could be used to determine the efficiency of in vitro osteogenic differentiation based on pluripotency, we measured the pluripotency pattern of cultures through stemness gene expression, proliferation ability and telomerase activity, measured by QCM. RESULTS: We showed that the pluripotency pattern determined by QCM was similar to the patterns of proliferation ability and gene expression, which showed a slight upregulation at the late stages, within the context of the general downregulation tendency during differentiation. Additionally, a comprehensive gene expression pattern covering nearly every stage of differentiation was identified. CONCLUSION: Therefore, this assay may be powerful tools for determining the efficiency of differentiation systems based on pluripotency. In this study, we not only introduce a new method for determining efficiency based on pluripotency, but also provide more information about the characteristics of osteogenic differentiation which help facilitate future development of more efficient protocols.


Subject(s)
Bone and Bones , Down-Regulation , Gene Expression , In Vitro Techniques , Methods , Mouse Embryonic Stem Cells , Osteoblasts , Pluripotent Stem Cells , Quartz Crystal Microbalance Techniques , Telomerase , Up-Regulation
17.
Rev. colomb. cir ; 32(2): 146-151, 20170000.
Article in Spanish | LILACS | ID: biblio-885085

ABSTRACT

La isquemia crítica de los miembros inferiores se define como la insuficiencia de flujo arterial a los miembros inferiores para mantener la viabilidad tisular, generalmente causada por enfermedad obstructiva arterial periférica. Las manifestaciones clínicas son dolor en reposo y presencia de úlceras o pérdida tisular espontánea. El manejo con reperfusión quirúrgica (surgical revascularization) y terapia endovascular ha permitido lograr salvamentos importantes de extremidades pero, a pesar de estos avances, aproximadamente, entre el 20 y el 40 % de los pacientes con isquemia crítica no son candidatos a ninguno de estos tratamientos. Se estima que anualmente se practican entre 120 y 500 amputaciones por cada millón de habitantes por enfermedad arterial; 25 % de los pacientes con amputaciones mayores no recibe ningún tipo de rehabilitación. Por lo tanto, se necesita contar con nuevas estrategias para promover el salvamento de extremidades y disminuir las tasas tan altas de amputaciones. En los últimos 20 años, el uso de células madre pluripotenciales ha demostrado ser un tratamiento efectivo y seguro para los pacientes con isquemia crítica con gran riesgo de pérdida de las extremidades


Critical ischemia of the lower limbs is defined as insufficiency of arterial flow to the lower limbs to maintain tissue viability, usually caused by obstructive peripheral arterial disease. The clinical manifestations are pain at rest and presence of ulcers or spontaneous tissue loss. Management with surgical revascularization and endovascular therapy has shown high limb salvage, but in spite of these advances approximately 20% to 40% of patients with critical limb ischemia are not candidates for any of these therapies. It is estimated that between 120 and 500 amputations are doing per year per million inhabitants per arterial disease; 25% of patients with major amputations do not receive rehabilitation. Therefore, we need new strategies to promote limb salvage and reduce such high amputation rates. The use of stem cells over the last 20 years has proven to be an effective and safe treatment for patients with critical ischemia with a high risk of limb loss


Subject(s)
Humans , Pluripotent Stem Cells , Ischemia , Peripheral Arterial Disease , Stem Cell Transplantation
18.
Appl. cancer res ; 37: 1-8, 2017. ilus
Article in English | LILACS, Inca | ID: biblio-915112

ABSTRACT

Induced Pluripotent Stem Cells (iPSCs) technology has catapulted the field of stem-cell biology through ectopic expression of reprogramming factors. Ever since its discovery, the potential of iPSCs has been explored by many scientists to unravel the molecular mechanism responsible for cancer initiation and progression. Besides modeling cancer, the further applications of this technology includes high-throughput drug screening, epigenetic reprogramming of cancer cell state to normal, immunotherapy and regenerative cell therapies. Here, we review the current challenges on clinical applications of iPSCs with respect to understanding cancer and personalizing treatment for the disease (AU)


Subject(s)
Humans , Stem Cells , Pluripotent Stem Cells , Molecular Mechanisms of Pharmacological Action , Neoplasms/therapy
19.
Protein & Cell ; (12): 315-327, 2017.
Article in English | WPRIM | ID: wpr-757335

ABSTRACT

Precision medicine emerges as a new approach that takes into account individual variability. Successful realization of precision medicine requires disease models that are able to incorporate personalized disease information and recapitulate disease development processes at the molecular, cellular and organ levels. With recent development in stem cell field, a variety of tissue organoids can be derived from patient specific pluripotent stem cells and adult stem cells. In combination with the state-of-the-art genome editing tools, organoids can be further engineered to mimic disease-relevant genetic and epigenetic status of a patient. This has therefore enabled a rapid expansion of sophisticated in vitro disease models, offering a unique system for fundamental and biomedical research as well as the development of personalized medicine. Here we summarize some of the latest advances and future perspectives in engineering stem cell organoids for human disease modeling.


Subject(s)
Animals , Biomedical Research , Gene Editing , Methods , Humans , Models, Biological , Organoids , Metabolism , Pluripotent Stem Cells , Metabolism , Precision Medicine , Methods
20.
Protein & Cell ; (12): 379-393, 2017.
Article in English | WPRIM | ID: wpr-757327

ABSTRACT

Human pluripotent stem cells (hPSCs) are an important system to study early human development, model human diseases, and develop cell replacement therapies. However, genetic manipulation of hPSCs is challenging and a method to simultaneously activate multiple genomic sites in a controllable manner is sorely needed. Here, we constructed a CRISPR-ON system to efficiently upregulate endogenous genes in hPSCs. A doxycycline (Dox) inducible dCas9-VP64-p65-Rta (dCas9-VPR) transcription activator and a reverse Tet transactivator (rtTA) expression cassette were knocked into the two alleles of the AAVS1 locus to generate an iVPR hESC line. We showed that the dCas9-VPR level could be precisely and reversibly controlled by the addition and withdrawal of Dox. Upon transfection of multiplexed gRNA plasmid targeting the NANOG promoter and Dox induction, we were able to control NANOG gene expression from its endogenous locus. Interestingly, an elevated NANOG level promoted naïve pluripotent gene expression, enhanced cell survival and clonogenicity, and enabled hESCs to integrate with the inner cell mass (ICM) of mouse blastocysts in vitro. Thus, iVPR cells provide a convenient platform for gene function studies as well as high-throughput screens in hPSCs.


Subject(s)
Animals , Cell Line , Clustered Regularly Interspaced Short Palindromic Repeats , Doxycycline , Pharmacology , Gene Expression Regulation , Human Embryonic Stem Cells , Metabolism , Humans , Mice , Nanog Homeobox Protein , Genetics , Pluripotent Stem Cells , Metabolism
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