Translational Application of Microfluidics and Bioprinting for Stem Cell-Based Cartilage Repair

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Silvia Lopa

2018-01-01

Full Text Available Cartilage defects can impair the most elementary daily activities and, if not properly treated, can lead to the complete loss of articular function. The limitations of standard treatments for cartilage repair have triggered the development of stem cell-based therapies. In this scenario, the development of efficient cell differentiation protocols and the design of proper biomaterial-based supports to deliver cells to the injury site need to be addressed through basic and applied research to fully exploit the potential of stem cells. Here, we discuss the use of microfluidics and bioprinting approaches for the translation of stem cell-based therapy for cartilage repair in clinics. In particular, we will focus on the optimization of hydrogel-based materials to mimic the articular cartilage triggered by their use as bioinks in 3D bioprinting applications, on the screening of biochemical and biophysical factors through microfluidic devices to enhance stem cell chondrogenesis, and on the use of microfluidic technology to generate implantable constructs with a complex geometry. Finally, we will describe some new bioprinting applications that pave the way to the clinical use of stem cell-based therapies, such as scaffold-free bioprinting and the development of a 3D handheld device for the in situ repair of cartilage defects.

Translational Application of Microfluidics and Bioprinting for Stem Cell-Based Cartilage Repair

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Mondadori, Carlotta; Mainardi, Valerio Luca; Talò, Giuseppe; Candrian, Christian; Święszkowski, Wojciech

2018-01-01

Cartilage defects can impair the most elementary daily activities and, if not properly treated, can lead to the complete loss of articular function. The limitations of standard treatments for cartilage repair have triggered the development of stem cell-based therapies. In this scenario, the development of efficient cell differentiation protocols and the design of proper biomaterial-based supports to deliver cells to the injury site need to be addressed through basic and applied research to fully exploit the potential of stem cells. Here, we discuss the use of microfluidics and bioprinting approaches for the translation of stem cell-based therapy for cartilage repair in clinics. In particular, we will focus on the optimization of hydrogel-based materials to mimic the articular cartilage triggered by their use as bioinks in 3D bioprinting applications, on the screening of biochemical and biophysical factors through microfluidic devices to enhance stem cell chondrogenesis, and on the use of microfluidic technology to generate implantable constructs with a complex geometry. Finally, we will describe some new bioprinting applications that pave the way to the clinical use of stem cell-based therapies, such as scaffold-free bioprinting and the development of a 3D handheld device for the in situ repair of cartilage defects. PMID:29535776

Therapeutic potential of stem cells in auditory hair cell repair

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Ryuji Hata

2009-01-01

Full Text Available The prevalence of acquired hearing loss is very high. About 10% of the total population and more than one third of the population over 65 years suffer from debilitating hearing loss. The most common type of hearing loss in adults is idiopathic sudden sensorineural hearing loss (ISSHL. In the majority of cases, ISSHL is permanent and typically associated with loss of sensory hair cells in the organ of Corti. Following the loss of sensory hair cells, the auditory neurons undergo secondary degeneration. Sensory hair cells and auditory neurons do not regenerate throughout life, and loss of these cells is irreversible and cumulative. However, recent advances in stem cell biology have gained hope that stem cell therapy comes closer to regenerating sensory hair cells in humans. A major advance in the prospects for the use of stem cells to restore normal hearing comes with the recent discovery that hair cells can be generated ex vivo from embryonic stem (ES cells, adult inner ear stem cells and neural stem cells. Furthermore, there is increasing evidence that stem cells can promote damaged cell repair in part by secreting diffusible molecules such as growth factors. These results suggest that stem-cell-based treatment regimens can be applicable to the damaged inner ear as future clinical applications.Previously we have established an animal model of cochlear ischemia in gerbils and showed progressive hair cell loss up to 4 days after ischemia. Auditory brain stem response (ABR recordings have demonstrated that this gerbil model displays severe deafness just after cochlear ischemia and gradually recovers thereafter. These pathological findings and clinical manifestations are reminiscent of ISSHL in humans. In this study, we have shown the effectiveness of stem cell therapy by using this animal model of ISSHL.

Stem Cells for Cartilage Repair: Preclinical Studies and Insights in Translational Animal Models and Outcome Measures

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Melissa Lo Monaco

2018-01-01

Full Text Available Due to the restricted intrinsic capacity of resident chondrocytes to regenerate the lost cartilage postinjury, stem cell-based therapies have been proposed as a novel therapeutic approach for cartilage repair. Moreover, stem cell-based therapies using mesenchymal stem cells (MSCs or induced pluripotent stem cells (iPSCs have been used successfully in preclinical and clinical settings. Despite these promising reports, the exact mechanisms underlying stem cell-mediated cartilage repair remain uncertain. Stem cells can contribute to cartilage repair via chondrogenic differentiation, via immunomodulation, or by the production of paracrine factors and extracellular vesicles. But before novel cell-based therapies for cartilage repair can be introduced into the clinic, rigorous testing in preclinical animal models is required. Preclinical models used in regenerative cartilage studies include murine, lapine, caprine, ovine, porcine, canine, and equine models, each associated with its specific advantages and limitations. This review presents a summary of recent in vitro data and from in vivo preclinical studies justifying the use of MSCs and iPSCs in cartilage tissue engineering. Moreover, the advantages and disadvantages of utilizing small and large animals will be discussed, while also describing suitable outcome measures for evaluating cartilage repair.

Stem Cells for Cartilage Repair: Preclinical Studies and Insights in Translational Animal Models and Outcome Measures.

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Lo Monaco, Melissa; Merckx, Greet; Ratajczak, Jessica; Gervois, Pascal; Hilkens, Petra; Clegg, Peter; Bronckaers, Annelies; Vandeweerd, Jean-Michel; Lambrichts, Ivo

2018-01-01

Due to the restricted intrinsic capacity of resident chondrocytes to regenerate the lost cartilage postinjury, stem cell-based therapies have been proposed as a novel therapeutic approach for cartilage repair. Moreover, stem cell-based therapies using mesenchymal stem cells (MSCs) or induced pluripotent stem cells (iPSCs) have been used successfully in preclinical and clinical settings. Despite these promising reports, the exact mechanisms underlying stem cell-mediated cartilage repair remain uncertain. Stem cells can contribute to cartilage repair via chondrogenic differentiation, via immunomodulation, or by the production of paracrine factors and extracellular vesicles. But before novel cell-based therapies for cartilage repair can be introduced into the clinic, rigorous testing in preclinical animal models is required. Preclinical models used in regenerative cartilage studies include murine, lapine, caprine, ovine, porcine, canine, and equine models, each associated with its specific advantages and limitations. This review presents a summary of recent in vitro data and from in vivo preclinical studies justifying the use of MSCs and iPSCs in cartilage tissue engineering. Moreover, the advantages and disadvantages of utilizing small and large animals will be discussed, while also describing suitable outcome measures for evaluating cartilage repair.

RAD51 Is a Selective DNA Repair Target to Radiosensitize Glioma Stem Cells.

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King, Harry O; Brend, Tim; Payne, Helen L; Wright, Alexander; Ward, Thomas A; Patel, Karan; Egnuni, Teklu; Stead, Lucy F; Patel, Anjana; Wurdak, Heiko; Short, Susan C

2017-01-10

Patients with glioblastoma die from local relapse despite surgery and high-dose radiotherapy. Resistance to radiotherapy is thought to be due to efficient DNA double-strand break (DSB) repair in stem-like cells able to survive DNA damage and repopulate the tumor. We used clinical samples and patient-derived glioblastoma stem cells (GSCs) to confirm that the DSB repair protein RAD51 is highly expressed in GSCs, which are reliant on RAD51-dependent DSB repair after radiation. RAD51 expression and RAD51 foci numbers fall when these cells move toward astrocytic differentiation. In GSCs, the small-molecule RAD51 inhibitors RI-1 and B02 prevent RAD51 focus formation, reduce DNA DSB repair, and cause significant radiosensitization. We further demonstrate that treatment with these agents combined with radiation promotes loss of stem cells defined by SOX2 expression. This indicates that RAD51-dependent repair represents an effective and specific target in GSCs. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Stem cell death and survival in heart regeneration and repair.

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Abdelwahid, Eltyeb; Kalvelyte, Audrone; Stulpinas, Aurimas; de Carvalho, Katherine Athayde Teixeira; Guarita-Souza, Luiz Cesar; Foldes, Gabor

2016-03-01

Cardiovascular diseases are major causes of mortality and morbidity. Cardiomyocyte apoptosis disrupts cardiac function and leads to cardiac decompensation and terminal heart failure. Delineating the regulatory signaling pathways that orchestrate cell survival in the heart has significant therapeutic implications. Cardiac tissue has limited capacity to regenerate and repair. Stem cell therapy is a successful approach for repairing and regenerating ischemic cardiac tissue; however, transplanted cells display very high death percentage, a problem that affects success of tissue regeneration. Stem cells display multipotency or pluripotency and undergo self-renewal, however these events are negatively influenced by upregulation of cell death machinery that induces the significant decrease in survival and differentiation signals upon cardiovascular injury. While efforts to identify cell types and molecular pathways that promote cardiac tissue regeneration have been productive, studies that focus on blocking the extensive cell death after transplantation are limited. The control of cell death includes multiple networks rather than one crucial pathway, which underlies the challenge of identifying the interaction between various cellular and biochemical components. This review is aimed at exploiting the molecular mechanisms by which stem cells resist death signals to develop into mature and healthy cardiac cells. Specifically, we focus on a number of factors that control death and survival of stem cells upon transplantation and ultimately affect cardiac regeneration. We also discuss potential survival enhancing strategies and how they could be meaningful in the design of targeted therapies that improve cardiac function.

Propofol promotes spinal cord injury repair by bone marrow mesenchymal stem cell transplantation

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Zhou, Ya-jing; Liu, Jian-min; Wei, Shu-ming; Zhang, Yun-hao; Qu, Zhen-hua; Chen, Shu-bo

2015-01-01

Propofol is a neuroprotective anesthetic. Whether propofol can promote spinal cord injury repair by bone marrow mesenchymal stem cells remains poorly understood. We used rats to investigate spinal cord injury repair using bone marrow mesenchymal stem cell transplantation combined with propofol administration via the tail vein. Rat spinal cord injury was clearly alleviated; a large number of newborn non-myelinated and myelinated nerve fibers appeared in the spinal cord, the numbers of CM-Dil-l...

Propofol promotes spinal cord injury repair by bone marrow mesenchymal stem cell transplantation

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Zhou, Ya-jing; Liu, Jian-min; Wei, Shu-ming; Zhang, Yun-hao; Qu, Zhen-hua; Chen, Shu-bo

2015-01-01

Propofol is a neuroprotective anesthetic. Whether propofol can promote spinal cord injury repair by bone marrow mesenchymal stem cells remains poorly understood. We used rats to investigate spinal cord injury repair using bone marrow mesenchymal stem cell transplantation combined with propofol administration via the tail vein. Rat spinal cord injury was clearly alleviated; a large number of newborn non-myelinated and myelinated nerve fibers appeared in the spinal cord, the numbers of CM-Dil-labeled bone marrow mesenchymal stem cells and fluorogold-labeled nerve fibers were increased and hindlimb motor function of spinal cord-injured rats was markedly improved. These improvements were more prominent in rats subjected to bone marrow mesenchymal cell transplantation combined with propofol administration than in rats receiving monotherapy. These results indicate that propofol can enhance the therapeutic effects of bone marrow mesenchymal stem cell transplantation on spinal cord injury in rats. PMID:26487860

Uninduced adipose-derived stem cells repair the defect of full-thickness hyaline cartilage.

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Zhang, Hai-Ning; Li, Lei; Leng, Ping; Wang, Ying-Zhen; Lv, Cheng-Yu

2009-04-01

To testify the effect of the stem cells derived from the widely distributed fat tissue on repairing full-thickness hyaline cartilage defects. Adipose-derived stem cells (ADSCs) were derived from adipose tissue and cultured in vitro. Twenty-seven New Zealand white rabbits were divided into three groups randomly. The cultured ADSCs mixed with calcium alginate gel were used to fill the full-thickness hyaline cartilage defects created at the patellafemoral joint, and the defects repaired with gel or without treatment served as control groups. After 4, 8 and 12 weeks, the reconstructed tissue was evaluated macroscopically and microscopically. Histological analysis and qualitative scoring were also performed to detect the outcome. Full thickness hyaline cartilage defects were repaired completely with ADSCs-derived tissue. The result was better in ADSCs group than the control ones. The microstructure of reconstructed tissue with ADSCs was similar to that of hyaline cartilage and contained more cells and regular matrix fibers, being better than other groups. Plenty of collagen fibers around cells could be seen under transmission electron microscopy. Statistical analysis revealed a significant difference in comparison with other groups at each time point (t equal to 4.360, P less than 0.01). These results indicate that stem cells derived from mature adipose without induction possess the ability to repair cartilage defects.

More efficient repair of DNA double-strand breaks in skeletal muscle stem cells compared to their committed progeny

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Leyla Vahidi Ferdousi

2014-11-01

Full Text Available The loss of genome integrity in adult stem cells results in accelerated tissue aging and is possibly cancerogenic. Adult stem cells in different tissues appear to react robustly to DNA damage. We report that adult skeletal stem (satellite cells do not primarily respond to radiation-induced DNA double-strand breaks (DSBs via differentiation and exhibit less apoptosis compared to other myogenic cells. Satellite cells repair these DNA lesions more efficiently than their committed progeny. Importantly, non-proliferating satellite cells and post-mitotic nuclei in the fiber exhibit dramatically distinct repair efficiencies. Altogether, reduction of the repair capacity appears to be more a function of differentiation than of the proliferation status of the muscle cell. Notably, satellite cells retain a high efficiency of DSB repair also when isolated from the natural niche. Finally, we show that repair of DSB substrates is not only very efficient but, surprisingly, also very accurate in satellite cells and that accurate repair depends on the key non-homologous end-joining factor DNA-PKcs.

More efficient repair of DNA double-strand breaks in skeletal muscle stem cells compared to their committed progeny.

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Vahidi Ferdousi, Leyla; Rocheteau, Pierre; Chayot, Romain; Montagne, Benjamin; Chaker, Zayna; Flamant, Patricia; Tajbakhsh, Shahragim; Ricchetti, Miria

2014-11-01

The loss of genome integrity in adult stem cells results in accelerated tissue aging and is possibly cancerogenic. Adult stem cells in different tissues appear to react robustly to DNA damage. We report that adult skeletal stem (satellite) cells do not primarily respond to radiation-induced DNA double-strand breaks (DSBs) via differentiation and exhibit less apoptosis compared to other myogenic cells. Satellite cells repair these DNA lesions more efficiently than their committed progeny. Importantly, non-proliferating satellite cells and post-mitotic nuclei in the fiber exhibit dramatically distinct repair efficiencies. Altogether, reduction of the repair capacity appears to be more a function of differentiation than of the proliferation status of the muscle cell. Notably, satellite cells retain a high efficiency of DSB repair also when isolated from the natural niche. Finally, we show that repair of DSB substrates is not only very efficient but, surprisingly, also very accurate in satellite cells and that accurate repair depends on the key non-homologous end-joining factor DNA-PKcs. Copyright © 2014. Published by Elsevier B.V.

Potential Roles of Dental Pulp Stem Cells in Neural Regeneration and Repair

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Luo, Lihua; Wang, Xiaoyan; Key, Brian; Lee, Bae Hoon

2018-01-01

This review summarizes current advances in dental pulp stem cells (DPSCs) and their potential applications in the nervous diseases. Injured adult mammalian nervous system has a limited regenerative capacity due to an insufficient pool of precursor cells in both central and peripheral nervous systems. Nerve growth is also constrained by inhibitory factors (associated with central myelin) and barrier tissues (glial scarring). Stem cells, possessing the capacity of self-renewal and multicellular differentiation, promise new therapeutic strategies for overcoming these impediments to neural regeneration. Dental pulp stem cells (DPSCs) derive from a cranial neural crest lineage, retain a remarkable potential for neuronal differentiation, and additionally express multiple factors that are suitable for neuronal and axonal regeneration. DPSCs can also express immunomodulatory factors that stimulate formation of blood vessels and enhance regeneration and repair of injured nerve. These unique properties together with their ready accessibility make DPSCs an attractive cell source for tissue engineering in injured and diseased nervous systems. In this review, we interrogate the neuronal differentiation potential as well as the neuroprotective, neurotrophic, angiogenic, and immunomodulatory properties of DPSCs and its application in the injured nervous system. Taken together, DPSCs are an ideal stem cell resource for therapeutic approaches to neural repair and regeneration in nerve diseases. PMID:29853908

Insulin-like growth factor-1 sustains stem cell mediated renal repair.

NARCIS (Netherlands)

Imberti, B.; Morigi, M.; Tomasoni, S.; Rota, C.; Corna, D.; Longaretti, L.; Rottoli, D.; Valsecchi, F.; Benigni, A.; Wang, J.; Abbate, M.; Zoja, C.; Remuzzi, G.

2007-01-01

In mice with cisplatin-induced acute kidney injury, administration of bone marrow-derived mesenchymal stem cells (MSC) restores renal tubular structure and improves renal function, but the underlying mechanism is unclear. Here, we examined the process of kidney cell repair in co-culture experiments

Differentiation of Human Induced Pluripotent or Embryonic Stem Cells Decreases the DNA Damage Repair by Homologous Recombination

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Kalpana Mujoo

2017-11-01

Full Text Available The nitric oxide (NO-cyclic GMP pathway contributes to human stem cell differentiation, but NO free radical production can also damage DNA, necessitating a robust DNA damage response (DDR to ensure cell survival. How the DDR is affected by differentiation is unclear. Differentiation of stem cells, either inducible pluripotent or embryonic derived, increased residual DNA damage as determined by γ-H2AX and 53BP1 foci, with increased S-phase-specific chromosomal aberration after exposure to DNA-damaging agents, suggesting reduced homologous recombination (HR repair as supported by the observation of decreased HR-related repair factor foci formation (RAD51 and BRCA1. Differentiated cells also had relatively increased fork stalling and R-loop formation after DNA replication stress. Treatment with NO donor (NOC-18, which causes stem cell differentiation has no effect on double-strand break (DSB repair by non-homologous end-joining but reduced DSB repair by HR. Present studies suggest that DNA repair by HR is impaired in differentiated cells.

Potential of human dental stem cells in repairing the complete transection of rat spinal cord

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Yang, Chao; Li, Xinghan; Sun, Liang; Guo, Weihua; Tian, Weidong

2017-04-01

Objective. The adult spinal cord of mammals contains a certain amount of neural precursor cells, but these endogenous cells have a limited capacity for replacement of lost cells after spinal cord injury. The exogenous stem cells transplantation has become a therapeutic strategy for spinal cord repairing because of their immunomodulatory and differentiation capacity. In addition, dental stem cells originating from the cranial neural crest might be candidate cell sources for neural engineering. Approach. Human dental follicle stem cells (DFSCs), stem cells from apical papilla (SCAPs) and dental pulp stem cells (DPSCs) were isolated and identified in vitro, then green GFP-labeled stem cells with pellets were transplanted into completely transected spinal cord. The functional recovery of rats and multiple neuro-regenerative mechanisms were explored. Main results. The dental stem cells, especially DFSCs, demonstrated the potential in repairing the completely transected spinal cord and promote functional recovery after injury. The major involved mechanisms were speculated below: First, dental stem cells inhibited the expression of interleukin-1β to reduce the inflammatory response; second, they inhibited the expression of ras homolog gene family member A (RhoA) to promote neurite regeneration; third, they inhibited the sulfonylurea receptor1 (SUR-1) expression to reduce progressive hemorrhagic necrosis; lastly, parts of the transplanted cells survived and differentiated into mature neurons and oligodendrocytes but not astrocyte, which is beneficial for promoting axons growth. Significance. Dental stem cells presented remarkable tissue regenerative capability after spinal cord injury through immunomodulatory, differentiation and protection capacity.

Mesenchymal Stem Cells in Tissue Repair

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Amy M DiMarino

2013-09-01

Full Text Available The advent of mesenchymal stem cell (MSC based therapies for clinical therapeutics has been an exciting and new innovation for the treatment of a variety of diseases associated with inflammation, tissue damage and subsequent regeneration and repair. Application-based ability to measure MSC potency and fate of the cells post-MSC therapy are the variables that confound the use of MSCs therapeutics in human diseases. An evaluation of MSC function and applications with attention to detail in the preparation as well as quality control (QC and quality assurance (QA are only as good as the assays that are developed. In vivo measures of efficacy and potency require an appreciation of the overall pathophysiology of the model and standardization of outcome measures. The new concepts of how MSC’s participate in the tissue regeneration and wound repair process and further, how this is impacted by estimates of efficacy and potency Are important new topics. In this regard,,, this chapter will review some of the in vitro and in vivo assays for MSC function and activity and their application to the clinical arena.

Further proof of the plasticity of adult stem cells and their role in tissue repair

OpenAIRE

Prockop, Darwin J.

2003-01-01

In this issue, De Bari et al. (2003) present elegant data to counter the recent claims that adult stem cells have a limited plasticity. Further, they provide evidence that adult stem cells can seek out damaged tissues and repair them.

Stem cells applications in bone and tooth repair and regeneration: New insights, tools, and hopes.

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Abdel Meguid, Eiman; Ke, Yuehai; Ji, Junfeng; El-Hashash, Ahmed H K

2018-03-01

The exploration of stem and progenitor cells holds promise for advancing our understanding of the biology of tissue repair and regeneration mechanisms after injury. This will also help in the future use of stem cell therapy for the development of regenerative medicine approaches for the treatment of different tissue-species defects or disorders such as bone, cartilages, and tooth defects or disorders. Bone is a specialized connective tissue, with mineralized extracellular components that provide bones with both strength and rigidity, and thus enable bones to function in body mechanical supports and necessary locomotion process. New insights have been added to the use of different types of stem cells in bone and tooth defects over the last few years. In this concise review, we briefly describe bone structure as well as summarize recent research progress and accumulated information regarding the osteogenic differentiation of stem cells, as well as stem cell contributions to bone repair/regeneration, bone defects or disorders, and both restoration and regeneration of bones and cartilages. We also discuss advances in the osteogenic differentiation and bone regeneration of dental and periodontal stem cells as well as in stem cell contributions to dentine regeneration and tooth engineering. © 2017 Wiley Periodicals, Inc.

A Preliminary Study: Human Fibroid Stro-1+/CD44+ Stem Cells Isolated From Uterine Fibroids Demonstrate Decreased DNA Repair and Genomic Integrity Compared to Adjacent Myometrial Stro-1+/CD44+ Cells.

Science.gov (United States)

Prusinski Fernung, Lauren E; Al-Hendy, Ayman; Yang, Qiwei

2018-01-01

Although uterine fibroids (UFs) continue to place a major burden on female reproductive health, the mechanisms behind their origin remain undetermined. Normal myometrial stem cells may be transformed into tumor-initiating stem cells, causing UFs, due to unknown causes of somatic mutations in MED12, found in up to 85% of sporadically formed UFs. It is well established in other tumor types that defective DNA repair increases the risk of such tumorigenic somatic mutations, mechanisms not yet studied in UFs. To examine the putative cause(s) of this stem cell transformation, we analyzed DNA repair within stem cells from human UFs compared to those from adjacent myometrium to determine whether DNA repair in fibroid stem cells is compromised. Human fibroid (F) and adjacent myometrial (Myo) stem cells were isolated from fresh tissues, and gene expression relating to DNA repair was analyzed. Fibroid stem cells differentially expressed DNA repair genes related to DNA double- (DSBs) and single-strand breaks. DNA damage was measured using alkaline comet assay. Additionally, DNA DSBs were induced in these stem cells and DNA DSB repair evaluated (1) by determining changes in phosphorylation of DNA DSB-related proteins and (2) by determining differences in γ-H2AX foci formation and relative DNA repair protein RAD50 expression. Overall, F stem cells demonstrated increased DNA damage and altered DNA repair gene expression and signaling, suggesting that human F stem cells demonstrate impaired DNA repair. Compromised F stem cell DNA repair may contribute to further mutagenesis and, consequently, further growth and propagation of UF tumors.

Stem cell-derived angiogenic/vasculogenic cells: Possible therapies for tissue repair and tissue engineering

NARCIS (Netherlands)

Zwaginga, J. J.; Doevendans, P.

2003-01-01

1. The recent ability to isolate stem cells and study their specific capacity of self-renewal with the formation of different cell types has opened up exciting vistas to help the repair of damaged tissue and even the formation of new tissue. In the present review, we deal with the characteristics

Transplantation of neurotrophin-3-transfected bone marrow mesenchymal stem cells for the repair of spinal cord injury.

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Dong, Yuzhen; Yang, Libin; Yang, Lin; Zhao, Hongxing; Zhang, Chao; Wu, Dapeng

2014-08-15

Bone marrow mesenchymal stem cell transplantation has been shown to be therapeutic in the repair of spinal cord injury. However, the low survival rate of transplanted bone marrow mesenchymal stem cells in vivo remains a problem. Neurotrophin-3 promotes motor neuron survival and it is hypothesized that its transfection can enhance the therapeutic effect. We show that in vitro transfection of neurotrophin-3 gene increases the number of bone marrow mesenchymal stem cells in the region of spinal cord injury. These results indicate that neurotrophin-3 can promote the survival of bone marrow mesenchymal stem cells transplanted into the region of spinal cord injury and potentially enhance the therapeutic effect in the repair of spinal cord injury.

Human embryonic stem cells have enhanced repair of multiple forms of DNA damage

DEFF Research Database (Denmark)

Maynard, Scott; Swistowska, Anna Maria; Lee, Jae Wan

2008-01-01

cells compared with various differentiated murine cells. Using single-cell gel electrophoresis (comet assay) we found that human embryonic stem cells (BG01, I6) have more efficient repair of different types of DNA damage (generated from H2O2, UV-C, ionizing radiation, or psoralen) than human primary...

Cell Therapy in Parkinson's Disease: Host Brain Repair Machinery Gets a Boost From Stem Cell Grafts.

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Napoli, Eleonora; Borlongan, Cesar V

2017-06-01

This commentary highlights the major findings and future research directions arising from the recent publication by Zuo and colleagues in Stem Cells 2017 (in press). Here, we discuss the novel observations that transplanted human neural stem cells can induce endogenous brain repair by specifically stimulating a host of regenerative processes in the neurogenic niche (i.e., subventricular zone [SVZ]) in an animal model of Parkinson's disease. That the identified therapeutic proteomes, neurotrophic factors, and anti-inflammatory cytokines in the SVZ may facilitate brain regeneration and behavioral recovery open a new venue of research for our understanding of the pathology and treatment of Parkinson's disease. Stem Cells 2017;35:1443-1445. © 2017 AlphaMed Press.

HORSE SPECIES SYMPOSIUM: Use of mesenchymal stem cells in fracture repair in horses.

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Govoni, K E

2015-03-01

Equine bone fractures are often catastrophic, potentially fatal, and costly to repair. Traditional methods of healing fractures have limited success, long recovery periods, and a high rate of reinjury. Current research in the equine industry has demonstrated that stem cell therapy is a promising novel therapy to improve fracture healing and reduce the incidence of reinjury; however, reports of success in horses have been variable and limited. Stem cells can be derived from embryonic, fetal, and adult tissue. Based on the ease of collection, opportunity for autologous cells, and proven success in other models, adipose- or bone marrow-derived mesenchymal stem cells (MSC) are often used in equine therapies. Methods for isolation, proliferation, and differentiation of MSC are well established in rodent and human models but are not well characterized in horses. There is recent evidence that equine bone marrow MSC are able to proliferate in culture for several passages in the presence of autologous and fetal bovine serum, which is important for expansion of cells. Mesenchymal stem cells have the capacity to differentiate into osteoblasts, the bone forming cells, and this complex process is regulated by a number of transcription factors including runt-related transcription factor 2 (Runx2) and osterix (Osx). However, it has not been well established if equine MSC are regulated in a similar manner. The data presented in this review support the view that equine bone marrow MSC are regulated by the same transcription factors that control the differentiation of rodent and human MSC into osteoblasts. Although stem cell therapy is promising in equine bone repair, additional research is needed to identify optimal methods for reintroduction and potential manipulations to improve their ability to form new bone.

Breast cancer stem cell-like cells are more sensitive to ionizing radiation than non-stem cells: role of ATM.

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Seog-Young Kim

Full Text Available There are contradictory observations about the different radiosensitivities of cancer stem cells and cancer non-stem cells. To resolve these contradictory observations, we studied radiosensitivities by employing breast cancer stem cell (CSC-like MDA-MB231 and MDA-MB453 cells as well as their corresponding non-stem cells. CSC-like cells proliferate without differentiating and have characteristics of tumor-initiating cells [1]. These cells were exposed to γ-rays (1.25-8.75 Gy and survival curves were determined by colony formation. A final slope, D(0, of the survival curve for each cell line was determined to measure radiosensitivity. The D(0 of CSC-like and non-stem MDA-MB-453 cells were 1.16 Gy and 1.55 Gy, respectively. Similar results were observed in MDA-MB-231 cells (0.94 Gy vs. 1.56 Gy. After determination of radiosensitivity, we investigated intrinsic cellular determinants which influence radiosensitivity including cell cycle distribution, free-radical scavengers and DNA repair. We observed that even though cell cycle status and antioxidant content may contribute to differential radiosensitivity, differential DNA repair capacity may be a greater determinant of radiosensitivity. Unlike non-stem cells, CSC-like cells have little/no sublethal damage repair, a low intracellular level of ataxia telangiectasia mutated (ATM and delay of γ-H2AX foci removal (DNA strand break repair. These results suggest that low DNA repair capacity is responsible for the high radiosensitivity of these CSC-like cells.

Fibroblast growth factor 2 and DNA repair involvement in the keratinocyte stem cells response to ionizing radiation

International Nuclear Information System (INIS)

Harfouche, L'Emira Ghida

2010-02-01

Keratinocyte stem cells (KSCs) from the human inter follicular epidermis are regarded as the major target to radiation during radiotherapy. We found herein that KSCs are more resistant to ionizing radiation than their direct progeny, and presented more rapid DNA damage repair kinetics than the progenitors. Furthermore, we provided evidence describing the effect of fibroblast growth factor 2 (FGF2) signaling on the ability of KSCs and progenitors to repair damaged DNA. Despite our knowledge of the fact, that FGF is an anti-apoptotic factor in multiple cell types, the direct link between DNA repair and FGF2 signaling has rarely been shown. Existence of such link is an important issue with implications not only to stem cell field but also to cancer therapy. (author)

CXCL12 Promotes Stem Cell Recruitment and Uterine Repair after Injury in Asherman’s Syndrome

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Gulcin Sahin Ersoy

2017-03-01

Full Text Available Asherman’s syndrome is an acquired condition of uterine fibrosis and adhesions in response to injury that adversely affects fertility and pregnancy. We have previously demonstrated that bone marrow-derived mesenchymal stem cells (BMDSCs contribute to uterine repair after injury and that stem cells supplementation improves fertility. Here, we demonstrate that CXCL12 is the chemokine that mediates stem cell engraftment and functional improvement using a murine model of Asherman’s syndrome. After uterine injury, we demonstrate that CXCL12 augmentation increased BMDSC engraftment and that the CXCL12 receptor (CXCR4 antagonist, ADM3100, blocked stem cell recruitment. CXCL12 reduced, whereas ADM3100 increased fibrosis. CXCL12 treatment led to improved fertility and litter size, whereas ADM3100 treatment reduced fertility and litter size. ADM3100 prevented optimal spontaneous uterine repair mediated by endogenous CXCL12 production, reducing pregnancies after injury in the absence of supplemental CXCL12 administration; however, ADM3100 treatment could be partially rescued by CXCL12 augmentation. CXCL12 or other CXCR4 receptor agonists may be useful in the treatment of infertility or adverse pregnancy outcomes in Asherman’s syndrome and other related uterine disorders.

Germline stem cell gene PIWIL2 mediates DNA repair through relaxation of chromatin.

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De-Tao Yin

Full Text Available DNA damage response (DDR is an intrinsic barrier of cell to tumorigenesis initiated by genotoxic agents. However, the mechanisms underlying the DDR are not completely understood despite of extensive investigation. Recently, we have reported that ectopic expression of germline stem cell gene PIWIL2 is associated with tumor stem cell development, although the underlying mechanisms are largely unknown. Here we show that PIWIL2 is required for the repair of DNA-damage induced by various types of genotoxic agents. Upon ultraviolet (UV irradiation, silenced PIWIL2 gene in normal human fibroblasts was transiently activated after treatment with UV light. This activation was associated with DNA repair, because Piwil2-deficienct mouse embryonic fibroblasts (mili(-/- MEFs were defective in cyclobutane pyrimidine dimers (CPD repair after UV treatment. As a result, the UV-treated mili(-/- MEFs were more susceptible to apoptosis, as characterized by increased levels of DNA damage-associated apoptotic proteins, such as active caspase-3, cleaved Poly (ADP-ribose polymerase (PARP and Bik. The impaired DNA repair in the mili(-/- MEFs was associated with the reductions of histone H3 acetylation and chromatin relaxation, although the DDR pathway downstream chromatin relaxation appeared not to be directly affected by Piwil2. Moreover, guanine-guanine (Pt-[GG] and double strand break (DSB repair were also defective in the mili(-/- MEFs treated by genotoxic chemicals Cisplatin and ionizing radiation (IR, respectively. The results indicate that Piwil2 can mediate DNA repair through an axis of Piwil2 → histone acetylation → chromatin relaxation upstream DDR pathways. The findings reveal a new role for Piwil2 in DNA repair and suggest that Piwil2 may act as a gatekeeper against DNA damage-mediated tumorigenesis.

Novel Stem Cell Therapies for Applications to Wound Healing and Tissue Repair.

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Grada, Ayman; Falanga, Vincent

2016-10-26

The number of individuals with chronic cutaneous wounds has been increasing worldwide due to an aging population, diabetes, obesity, and cardiovascular disease. In the United States, almost seven million Americans have chronic skin ulcers. Many therapeutic approaches have been used. However, the treatment outcomes are not always ideal because of failure to achieve complete wound closure in around 60% of cases, scarring, and high rate of recurrence. Therefore, there is a need for more effective therapies. Stem cells offer promising possibilities. Pre-clinical studies have shown that bone- or adipose tissue-derived mesenchymal stem cells (MSCs) have a competitive advantage over other types of stem cells due to their better defined multipotent differentiating potential, paracrine effects, immunomodulatory properties, and safety. However, large controlled clinical trials are needed to examine the capabilities of MSCs in humans and to assess their safety profile. In this review, we highlight emerging treatments in tissue regeneration and repair and provide some perspectives on how to translate current knowledge about stem cells-both multipotent and pluripotent-into viable clinical approaches for treating patients with difficult to heal wounds.

Mesenchymal stem cells overexpressing Ihh promote bone repair.

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Zou, Shasha; Chen, Tingting; Wang, Yanan; Tian, Ruhui; Zhang, Lingling; Song, Pingping; Yang, Shi; Zhu, Yong; Guo, Xizhi; Huang, Yiran; Li, Zheng; Kan, Lixin; Hu, Hongliang

2014-10-28

Indian hedgehog (Ihh) signaling pathway is known to play key roles in various aspects of normal endochondral bone development. This study tested the potential roles of high Ihh signaling in the context of injury-induced bone regeneration. A rabbit tibia defect model was established to test the effects of the implant of Ihh/mesenchymal stem cells (MSCs)/scaffold complex. Computed tomography (CT), gross observation, and standard histological and immunohistological techniques were used to evaluate the effectiveness of the treatment. In vitro studies with MSCs and C3H10T1/2 cells were also employed to further understand the cellular and molecular mechanisms. We found that the implanted Ihh/MSCs/scaffold complex promoted bone repair. Consistently, in vitro study found that Ihh induced the upregulation of chondrocytic, osteogenic, and vascular cell markers, both in C3H10T1/2 cells and MSCs. Our study has demonstrated that high Ihh signaling in a complex with MSCs enhanced bone regeneration effectively in a clinically relevant acute injury model. Even though the exact underlying mechanisms are still far from clear, our primary data suggested that enhanced chondrogenesis, osteogenesis, and angiogenesis of MSCs at least partially contribute to the process. This study not only has implications for basic research of MSCs and Ihh signaling pathway but also points to the possibility of direct application of this specific paradigm to clinical bone repair.

More efficient repair of DNA double-strand breaks in skeletal muscle stem cells compared to their committed progeny

OpenAIRE

Leyla Vahidi Ferdousi; Pierre Rocheteau; Romain Chayot; Benjamin Montagne; Zayna Chaker; Patricia Flamant; Shahragim Tajbakhsh; Miria Ricchetti

2014-01-01

International audience; The loss of genome integrity in adult stem cells results in accelerated tissue aging and is possibly cancerogenic. Adult stem cells in different tissues appear to react robustly to DNA damage. We report that adult skeletal stem (satellite) cells do not primarily respond to radiation-induced DNA double-strand breaks (DSBs) via differentiation and exhibit less apoptosis compared to other myogenic cells. Satellite cells repair these DNA lesions more efficiently than their...

Exploiting endogenous fibrocartilage stem cells to regenerate cartilage and repair joint injury

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Embree, Mildred C.; Chen, Mo; Pylawka, Serhiy; Kong, Danielle; Iwaoka, George M.; Kalajzic, Ivo; Yao, Hai; Shi, Chancheng; Sun, Dongming; Sheu, Tzong-Jen; Koslovsky, David A.; Koch, Alia; Mao, Jeremy J.

2016-01-01

Tissue regeneration using stem cell-based transplantation faces many hurdles. Alternatively, therapeutically exploiting endogenous stem cells to regenerate injured or diseased tissue may circumvent these challenges. Here we show resident fibrocartilage stem cells (FCSCs) can be used to regenerate and repair cartilage. We identify FCSCs residing within the superficial zone niche in the temporomandibular joint (TMJ) condyle. A single FCSC spontaneously generates a cartilage anlage, remodels into bone and organizes a haematopoietic microenvironment. Wnt signals deplete the reservoir of FCSCs and cause cartilage degeneration. We also show that intra-articular treatment with the Wnt inhibitor sclerostin sustains the FCSC pool and regenerates cartilage in a TMJ injury model. We demonstrate the promise of exploiting resident FCSCs as a regenerative therapeutic strategy to substitute cell transplantation that could be beneficial for patients suffering from fibrocartilage injury and disease. These data prompt the examination of utilizing this strategy for other musculoskeletal tissues. PMID:27721375

Transplantation of neurotrophin-3-transfected bone marrow mesenchymal stem cells for the repair of spinal cord injury

OpenAIRE

Dong, Yuzhen; Yang, Libin; Yang, Lin; Zhao, Hongxing; Zhang, Chao; Wu, Dapeng

2014-01-01

Bone marrow mesenchymal stem cell transplantation has been shown to be therapeutic in the repair of spinal cord injury. However, the low survival rate of transplanted bone marrow mesenchymal stem cells in vivo remains a problem. Neurotrophin-3 promotes motor neuron survival and it is hypothesized that its transfection can enhance the therapeutic effect. We show that in vitro transfection of neurotrophin-3 gene increases the number of bone marrow mesenchymal stem cells in the region of spinal ...

Stem Cell Therapies in Orthopaedic Trauma

OpenAIRE

Marcucio, Ralph S.; Nauth, Aaron; Giannoudis, Peter V.; Bahney, Chelsea; Piuzzi, Nicolas S.; Muschler, George; Miclau, Theodore

2015-01-01

Stem cells offer great promise to help understand the normal mechanisms of tissue renewal, regeneration, and repair, and also for development of cell-based therapies to treat patients after tissue injury. Most adult tissues contain stem cells and progenitor cells that contribute to homeostasis, remodeling and repair. Multiple stem and progenitor cell populations in bone are found in the marrow, the endosteum, and the periosteum. They contribute to the fracture healing process after injury and...

Bone regeneration and stem cells

DEFF Research Database (Denmark)

Arvidson, K; Abdallah, B M; Applegate, L A

2011-01-01

cells, use of platelet rich plasma for tissue repair, osteogenesis and its molecular markers. A variety of cells in addition to stem cells, as well as advances in materials science to meet specific requirements for bone and soft tissue regeneration by addition of bioactive molecules, are discussed.......This invited review covers research areas of central importance for orthopedic and maxillofacial bone tissue repair, including normal fracture healing and healing problems, biomaterial scaffolds for tissue engineering, mesenchymal and fetal stem cells, effects of sex steroids on mesenchymal stem...

ALDH1A1 maintains ovarian cancer stem cell-like properties by altered regulation of cell cycle checkpoint and DNA repair network signaling.

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Erhong Meng

Full Text Available OBJECTIVE: Aldehyde dehydrogenase (ALDH expressing cells have been characterized as possessing stem cell-like properties. We evaluated ALDH+ ovarian cancer stem cell-like properties and their role in platinum resistance. METHODS: Isogenic ovarian cancer cell lines for platinum sensitivity (A2780 and platinum resistant (A2780/CP70 as well as ascites from ovarian cancer patients were analyzed for ALDH+ by flow cytometry to determine its association to platinum resistance, recurrence and survival. A stable shRNA knockdown model for ALDH1A1 was utilized to determine its effect on cancer stem cell-like properties, cell cycle checkpoints, and DNA repair mediators. RESULTS: ALDH status directly correlated to platinum resistance in primary ovarian cancer samples obtained from ascites. Patients with ALDHHIGH displayed significantly lower progression free survival than the patients with ALDHLOW cells (9 vs. 3 months, respectively p<0.01. ALDH1A1-knockdown significantly attenuated clonogenic potential, PARP-1 protein levels, and reversed inherent platinum resistance. ALDH1A1-knockdown resulted in dramatic decrease of KLF4 and p21 protein levels thereby leading to S and G2 phase accumulation of cells. Increases in S and G2 cells demonstrated increased expression of replication stress associated Fanconi Anemia DNA repair proteins (FANCD2, FANCJ and replication checkpoint (pS317 Chk1 were affected. ALDH1A1-knockdown induced DNA damage, evidenced by robust induction of γ-H2AX and BAX mediated apoptosis, with significant increases in BRCA1 expression, suggesting ALDH1A1-dependent regulation of cell cycle checkpoints and DNA repair networks in ovarian cancer stem-like cells. CONCLUSION: This data suggests that ovarian cancer cells expressing ALDH1A1 may maintain platinum resistance by altered regulation of cell cycle checkpoint and DNA repair network signaling.

Human induced pluripotent cells resemble embryonic stem cells demonstrating enhanced levels of DNA repair and efficacy of nonhomologous end-joining

Energy Technology Data Exchange (ETDEWEB)

Fan Jinshui; Robert, Carine [Department of Radiation Oncology, University of Maryland School of Medicine, 655 West Baltimore Street, BRB 7-023A, Baltimore, MD 21201 (United States); Jang, Yoon-Young; Liu Hua; Sharkis, Saul; Baylin, Stephen Bruce [Johns Hopkins University School of Medicine, Department of Oncology, Baltimore, MD 21231-1000 (United States); Rassool, Feyruz Virgilia, E-mail: frassool@som.umaryland.edu [Department of Radiation Oncology, University of Maryland School of Medicine, 655 West Baltimore Street, BRB 7-023A, Baltimore, MD 21201 (United States)

2011-08-01

Highlights: {yields} iPSC and hESC demonstrate a similar cell cycle profile, with increased S phase cells and decreased G0/G1. {yields} iPSC and hESC increased ROS and decreased DSBs, compared with differentiated parental cells. {yields} iPSC and hESC demonstrate elevated DSB repair activity, including nonhomologous end-joining, compared with differentiated parental cells. {yields} iPSC however show a partial apoptotic response to DNA damage, compared to hESC. {yields} DNA damage responses may constitute important markers for the efficacy of iPSC reprogramming. - Abstract: To maintain the integrity of the organism, embryonic stem cells (ESC) need to maintain their genomic integrity in response to DNA damage. DNA double strand breaks (DSBs) are one of the most lethal forms of DNA damage and can have disastrous consequences if not repaired correctly, leading to cell death, genomic instability and cancer. How human ESC (hESC) maintain genomic integrity in response to agents that cause DSBs is relatively unclear. Adult somatic cells can be induced to 'dedifferentiate' into induced pluripotent stem cells (iPSC) and reprogram into cells of all three germ layers. Whether iPSC have reprogrammed the DNA damage response is a critical question in regenerative medicine. Here, we show that hESC demonstrate high levels of endogenous reactive oxygen species (ROS) which can contribute to DNA damage and may arise from high levels of metabolic activity. To potentially counter genomic instability caused by DNA damage, we find that hESC employ two strategies: First, these cells have enhanced levels of DNA repair proteins, including those involved in repair of DSBs, and they demonstrate elevated nonhomologous end-joining (NHEJ) activity and repair efficacy, one of the main pathways for repairing DSBs. Second, they are hypersensitive to DNA damaging agents, as evidenced by a high level of apoptosis upon irradiation. Importantly, iPSC, unlike the parent cells they are derived

Human induced pluripotent cells resemble embryonic stem cells demonstrating enhanced levels of DNA repair and efficacy of nonhomologous end-joining

International Nuclear Information System (INIS)

Fan Jinshui; Robert, Carine; Jang, Yoon-Young; Liu Hua; Sharkis, Saul; Baylin, Stephen Bruce; Rassool, Feyruz Virgilia

2011-01-01

Highlights: → iPSC and hESC demonstrate a similar cell cycle profile, with increased S phase cells and decreased G0/G1. → iPSC and hESC increased ROS and decreased DSBs, compared with differentiated parental cells. → iPSC and hESC demonstrate elevated DSB repair activity, including nonhomologous end-joining, compared with differentiated parental cells. → iPSC however show a partial apoptotic response to DNA damage, compared to hESC. → DNA damage responses may constitute important markers for the efficacy of iPSC reprogramming. - Abstract: To maintain the integrity of the organism, embryonic stem cells (ESC) need to maintain their genomic integrity in response to DNA damage. DNA double strand breaks (DSBs) are one of the most lethal forms of DNA damage and can have disastrous consequences if not repaired correctly, leading to cell death, genomic instability and cancer. How human ESC (hESC) maintain genomic integrity in response to agents that cause DSBs is relatively unclear. Adult somatic cells can be induced to 'dedifferentiate' into induced pluripotent stem cells (iPSC) and reprogram into cells of all three germ layers. Whether iPSC have reprogrammed the DNA damage response is a critical question in regenerative medicine. Here, we show that hESC demonstrate high levels of endogenous reactive oxygen species (ROS) which can contribute to DNA damage and may arise from high levels of metabolic activity. To potentially counter genomic instability caused by DNA damage, we find that hESC employ two strategies: First, these cells have enhanced levels of DNA repair proteins, including those involved in repair of DSBs, and they demonstrate elevated nonhomologous end-joining (NHEJ) activity and repair efficacy, one of the main pathways for repairing DSBs. Second, they are hypersensitive to DNA damaging agents, as evidenced by a high level of apoptosis upon irradiation. Importantly, iPSC, unlike the parent cells they are derived from, mimic hESC in their ROS levels

Bone regeneration and stem cells

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Arvidson, K; Abdallah, B M; Applegate, L A; Baldini, N; Cenni, E; Gomez-Barrena, E; Granchi, D; Kassem, M; Konttinen, Y T; Mustafa, K; Pioletti, D P; Sillat, T; Finne-Wistrand, A

2011-01-01

Abstract This invited review covers research areas of central importance for orthopaedic and maxillofacial bone tissue repair, including normal fracture healing and healing problems, biomaterial scaffolds for tissue engineering, mesenchymal and foetal stem cells, effects of sex steroids on mesenchymal stem cells, use of platelet-rich plasma for tissue repair, osteogenesis and its molecular markers. A variety of cells in addition to stem cells, as well as advances in materials science to meet specific requirements for bone and soft tissue regeneration by addition of bioactive molecules, are discussed. PMID:21129153

Muscle Stem Cells: A Model System for Adult Stem Cell Biology.

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Cornelison, Ddw; Perdiguero, Eusebio

2017-01-01

Skeletal muscle stem cells, originally termed satellite cells for their position adjacent to differentiated muscle fibers, are absolutely required for the process of skeletal muscle repair and regeneration. In the last decade, satellite cells have become one of the most studied adult stem cell systems and have emerged as a standard model not only in the field of stem cell-driven tissue regeneration but also in stem cell dysfunction and aging. Here, we provide background in the field and discuss recent advances in our understanding of muscle stem cell function and dysfunction, particularly in the case of aging, and the potential involvement of muscle stem cells in genetic diseases such as the muscular dystrophies.

Stem Cells and Gene Therapy for Cartilage Repair

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Umile Giuseppe Longo

2012-01-01

Full Text Available Cartilage defects represent a common problem in orthopaedic practice. Predisposing factors include traumas, inflammatory conditions, and biomechanics alterations. Conservative management of cartilage defects often fails, and patients with this lesions may need surgical intervention. Several treatment strategies have been proposed, although only surgery has been proved to be predictably effective. Usually, in focal cartilage defects without a stable fibrocartilaginous repair tissue formed, surgeons try to promote a natural fibrocartilaginous response by using marrow stimulating techniques, such as microfracture, abrasion arthroplasty, and Pridie drilling, with the aim of reducing swelling and pain and improving joint function of the patients. These procedures have demonstrated to be clinically useful and are usually considered as first-line treatment for focal cartilage defects. However, fibrocartilage presents inferior mechanical and biochemical properties compared to normal hyaline articular cartilage, characterized by poor organization, significant amounts of collagen type I, and an increased susceptibility to injury, which ultimately leads to premature osteoarthritis (OA. Therefore, the aim of future therapeutic strategies for articular cartilage regeneration is to obtain a hyaline-like cartilage repair tissue by transplantation of tissues or cells. Further studies are required to clarify the role of gene therapy and mesenchimal stem cells for management of cartilage lesions.

CD133 positive U87 glioma stem cell radiosensitivity and DNA double-strand break repair

International Nuclear Information System (INIS)

Li Ping; Zong Tianzhou; Ji Xiaoqin; Lu Xueguan

2013-01-01

Objective: To explore the radiosensitivity and DNA double-strand break repair of CD133 + U87 glioma stem cell. Methods: CD133 + and CD133 - cells were isolated from glioma U87 cell lines by flow cytometry sorter system. After irradiated vertically by 4 Gy X-rays, the radiosensitivity of cells was determined by clonogenic assay. The radiation-induced DNA double-strand break repair of CD133 + and CD133 - cells was determined by the neutral comet assay,and the expression of phosphorylated histone H2AX (γ-H2AX) and Rad51 foci were measured by immunofluorescence. Results: The clone forming rate of CD133 + cells was higher than CD133 - cells (t=3.66, P<0.01) with no radiation. The clone forming rate of CD133 + cells irradiated by 4 Gy X-rays has no significant changes compared to that of the non-irradiation cells (t=0.71, P>0.05), but for CD133 - cells, it decreased compared to non-irradiation cells (t=2.91, P<0.05). The tailmoment between CD133 + cells and CD133 - cells had no difference at 0.5 h after irradiation (t=1.44, P>0.05); the tailmoment of CD133 + cells was lower than CD133 - cells at 6 and 24 h after irradiation,respectively (t=5.31 and 8.09, P<0.01). There was no significant difference in the expression of γ-H2AX foci between CD133 + and CD133 - cells at 0.5 and 6 h after irradiation (t=0.12 and 0.99, P>0.05), γ-H2AX foci of CD133 + cells was significantly decreased compared to CD133 - cells at 24 h after irradiation (t=4.99, P<0.01). For Rad 51 foci, there was no difference between CD133 + and CD133 - cells at 0.5 h after irradiation (t=1.12, P>0.05). The expression of Rad 51 foci of CD133 - cells was decreased compared to that of CD133 + cells at 6 and 24 h after irradiation,respectively (t=22.88 and 12.43, P<0.01). And the expression of Rad51 foci of CD133 + cells had no significant changes at 6-24 h after irradiation. Conclusions: Glioma stem cells is more radioresistive than glioma non-stem cells. The probable mechanism is that the DNA double

Tissue engineering and the use of stem/progenitor cells for airway epithelium repair

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GM Roomans

2010-06-01

Full Text Available Stem/progenitor cells can be used to repair defects in the airway wall, resulting from e.g., tumors, trauma, tissue reactions following long-time intubations, or diseases that are associated with epithelial damage. Several potential sources of cells for airway epithelium have been identified. These can be divided into two groups. The first group consists of endogenous progenitor cells present in the respiratory tract. This group can be subdivided according to location into (a a ductal cell type in the submucosal glands of the proximal trachea, (b basal cells in the intercartilaginous zones of the lower trachea and bronchi, (c variant Clara cells (Clarav-cells in the bronchioles and (d at the junctions between the bronchioles and the alveolar ducts, and (e alveolar type II cells. This classification of progenitor cell niches is, however, controversial. The second group consists of exogenous stem cells derived from other tissues in the body. This second group can be subdivided into: (a embryonic stem (ES cells, induced pluripotent stem (iPS cells, or amniotic fluid stem cells, (b side-population cells from bone marrow or epithelial stem cells present in bone marrow or circulation and (c fat-derived mesenchymal cells. Airway epithelial cells can be co-cultured in a system that includes a basal lamina equivalent, extracellular factors from mesenchymal fibroblasts, and in an air-liquid interface system. Recently, spheroid-based culture systems have been developed. Several clinical applications have been suggested: cystic fibrosis, acute respiratory distress syndrome, chronic obstructive lung disease, pulmonary fibrosis, pulmonary edema, and pulmonary hypertension. Clinical applications so far are few, but include subglottic stenosis, tracheomalacia, bronchiomalacia, and emphysema.

Identification of Drugs that Regulate Dermal Stem Cells and Enhance Skin Repair

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Sibel Naska

2016-01-01

Full Text Available Here, we asked whether we could identify pharmacological agents that enhance endogenous stem cell function to promote skin repair, focusing on skin-derived precursors (SKPs, a dermal precursor cell population. Libraries of compounds already used in humans were screened for their ability to enhance the self-renewal of human and rodent SKPs. We identified and validated five such compounds, and showed that two of them, alprostadil and trimebutine maleate, enhanced the repair of full thickness skin wounds in middle-aged mice. Moreover, SKPs isolated from drug-treated skin displayed long-term increases in self-renewal when cultured in basal growth medium without drugs. Both alprostadil and trimebutine maleate likely mediated increases in SKP self-renewal by moderate hyperactivation of the MEK-ERK pathway. These findings identify candidates for potential clinical use in human skin repair, and provide support for the idea that pharmacological activation of endogenous tissue precursors represents a viable therapeutic strategy.

Enhancement of the repair of dog alveolar cleft by an autologous iliac bone, bone marrow-derived mesenchymal stem cell, and platelet-rich fibrin mixture.

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Yuanzheng, Chen; Yan, Gao; Ting, Li; Yanjie, Fu; Peng, Wu; Nan, Bai

2015-05-01

Autologous bone graft has been regarded as the criterion standard for the repair of alveolar cleft. However, the most prominent issue in alveolar cleft treatment is the high absorption rate of the bone graft. The authors' objective was to investigate the effects of an autologous iliac bone, bone marrow-derived mesenchymal stem cell, and platelet-rich fibrin mixture on the repair of dog alveolar cleft. Twenty beagle dogs with unilateral alveolar clefts created by surgery were divided randomly into four groups: group A underwent repair with an autologous iliac bone, bone marrow-derived mesenchymal stem cell, and platelet-rich fibrin mixture; group B underwent repair with autologous iliac bone and bone marrow-derived mesenchymal stem cells; group C underwent repair with autologous iliac bone and platelet-rich fibrin; and group D underwent repair with autologous iliac bone as the control. One day and 6 months after transplantation, the transplant volumes and bone mineral density were assessed by quantitative computed tomography. All of the transplants were harvested for hematoxylin and eosin staining 6 months later. Bone marrow-derived mesenchymal stem cells and platelet-rich fibrin transplants formed the greatest amounts of new bone among the four groups. The new bone formed an extensive union with the underlying maxilla in groups A, B, and C. Transplants with the bone marrow-derived mesenchymal stem cells, platelet-rich fibrin, and their mixture retained the majority of their initial volume, whereas the transplants in the control group showed the highest absorption rate. Bone mineral density of transplants with the bone marrow-derived mesenchymal stem cells, platelet-rich fibrin, and their mixture 6 months later was significantly higher than in the control group (p platelet-rich fibrin mixed transplants. Hematoxylin and eosin staining showed that the structure of new bones formed the best in group A. Both bone marrow-derived mesenchymal stem cells and platelet

Reprogramming Cells for Brain Repair

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Randall D. McKinnon

2013-08-01

Full Text Available At present there are no clinical therapies that can repair traumatic brain injury, spinal cord injury or degenerative brain disease. While redundancy and rewiring of surviving circuits can recover some lost function, the brain and spinal column lack sufficient endogenous stem cells to replace lost neurons or their supporting glia. In contrast, pre-clinical studies have demonstrated that exogenous transplants can have remarkable efficacy for brain repair in animal models. Mesenchymal stromal cells (MSCs can provide paracrine factors that repair damage caused by ischemic injury, and oligodendrocyte progenitor cell (OPC grafts give dramatic functional recovery from spinal cord injury. These studies have progressed to clinical trials, including human embryonic stem cell (hESC-derived OPCs for spinal cord repair. However, ESC-derived allografts are less than optimal, and we need to identify a more appropriate donor graft population. The cell reprogramming field has developed the ability to trans-differentiate somatic cells into distinct cell types, a technology that has the potential to generate autologous neurons and glia which address the histocompatibility concerns of allografts and the tumorigenicity concerns of ESC-derived grafts. Further clarifying how cell reprogramming works may lead to more efficient direct reprogram approaches, and possibly in vivo reprogramming, in order to promote brain and spinal cord repair.

Molecular phenotyping of human ovarian cancer stem cells unravels the mechanisms for repair and chemoresistance

DEFF Research Database (Denmark)

Alvero, Ayesha B; Chen, Rui; Fu, Han-Hsuan

2009-01-01

A major burden in the treatment of ovarian cancer is the high percentage of recurrence and chemoresistance. Cancer stem cells (CSCs) provide a reservoir of cells that can self-renew, can maintain the tumor by generating differentiated cells [non-stem cells (non-CSCs)] which make up the bulk...... to form spheroids in suspension, and the ability to recapitulate in vivo the original tumor. Chemotherapy eliminates the bulk of the tumor but it leaves a core of cancer cells with high capacity for repair and renewal. The molecular properties identified in these cells may explain some of the unique...... of the tumor and may be the primary source of recurrence. We describe the characterization of human ovarian cancer stem cells (OCSCs). These cells have a distinctive genetic profile that confers them with the capacity to recapitulate the original tumor, proliferate with chemotherapy, and promote recurrence...

Adipose, Bone Marrow and Synovial Joint-Derived Mesenchymal Stem Cells for Cartilage Repair

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Fellows, Christopher R.; Matta, Csaba; Zakany, Roza; Khan, Ilyas M.; Mobasheri, Ali

2016-01-01

Current cell-based repair strategies have proven unsuccessful for treating cartilage defects and osteoarthritic lesions, consequently advances in innovative therapeutics are required and mesenchymal stem cell-based (MSC) therapies are an expanding area of investigation. MSCs are capable of differentiating into multiple cell lineages and exerting paracrine effects. Due to their easy isolation, expansion, and low immunogenicity, MSCs are an attractive option for regenerative medicine for joint repair. Recent studies have identified several MSC tissue reservoirs including in adipose tissue, bone marrow, cartilage, periosteum, and muscle. MSCs isolated from these discrete tissue niches exhibit distinct biological activities, and have enhanced regenerative potentials for different tissue types. Each MSC type has advantages and disadvantages for cartilage repair and their use in a clinical setting is a balance between expediency and effectiveness. In this review we explore the challenges associated with cartilage repair and regeneration using MSC-based cell therapies and provide an overview of phenotype, biological activities, and functional properties for each MSC population. This paper also specifically explores the therapeutic potential of each type of MSC, particularly focusing on which cells are capable of producing stratified hyaline-like articular cartilage regeneration. Finally we highlight areas for future investigation. Given that patients present with a variety of problems it is unlikely that cartilage regeneration will be a simple “one size fits all,” but more likely an array of solutions that need to be applied systematically to achieve regeneration of a biomechanically competent repair tissue. PMID:28066501

Adipose, Bone Marrow and Synovial Joint-derived Mesenchymal Stem Cells for Cartilage Repair

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Christopher Fellows

2016-12-01

Full Text Available Current cell-based repair strategies have proven unsuccessful for treating cartilage defects and osteoarthritic lesions, consequently advances in innovative therapeutics are required and mesenchymal stem cell-based (MSC therapies are an expanding area of investigation. MSCs are capable of differentiating into multiple cell lineages and exerting paracrine effects. Due to their easy isolation, expansion and low immunogenicity, MSCs are an attractive option for regenerative medicine for joint repair. Recent studies have identified several MSC tissue reservoirs including in adipose tissue, bone marrow, cartilage, periosteum and muscle. MSCs isolated from these discrete tissue niches exhibit distinct biological activities, and have enhanced regenerative potentials for different tissue types. Each MSC type has advantages and disadvantages for cartilage repair and their use in a clinical setting is a balance between expediency and effectiveness. In this review we explore the challenges associated with cartilage repair and regeneration using MSC-based cell therapies and provide an overview of phenotype, biological activities and functional properties for each MSC population. This paper also specifically explores the therapeutic potential of each type of MSC, particularly focusing on which cells are capable of producing stratified hyaline-like articular cartilage regeneration. Finally we highlight areas for future investigation. Given that patients present with a variety of problems it is unlikely that cartilage regeneration will be a simple ‘one size fits all’, but more likely an array of solutions that need to applied systematically to achieve regeneration of a biomechanically competent repair tissue.

Neural crest stem cell population in craniomaxillofacial development and tissue repair

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M La Noce

2014-10-01

Full Text Available Neural crest cells, delaminating from the neural tube during migration, undergo an epithelial-mesenchymal transition and differentiate into several cell types strongly reinforcing the mesoderm of the craniofacial body area – giving rise to bone, cartilage and other tissues and cells of this human body area. Recent studies on craniomaxillofacial neural crest-derived cells have provided evidence for the tremendous plasticity of these cells. Actually, neural crest cells can respond and adapt to the environment in which they migrate and the cranial mesoderm plays an important role toward patterning the identity of the migrating neural crest cells. In our experience, neural crest-derived stem cells, such as dental pulp stem cells, can actively proliferate, repair bone and give rise to other tissues and cytotypes, including blood vessels, smooth muscle, adipocytes and melanocytes, highlighting that their use in tissue engineering is successful. In this review, we provide an overview of the main pathways involved in neural crest formation, delamination, migration and differentiation; and, in particular, we concentrate our attention on the translatability of the latest scientific progress. Here we try to suggest new ideas and strategies that are needed to fully develop the clinical use of these cells. This effort should involve both researchers/clinicians and improvements in good manufacturing practice procedures. It is important to address studies towards clinical application or take into consideration that studies must have an effective therapeutic prospect for humans. New approaches and ideas must be concentrated also toward stem cell recruitment and activation within the human body, overcoming the classical grafting.

Epidermal stem cells response to radiative genotoxic stress

International Nuclear Information System (INIS)

Marie, Melanie

2013-01-01

Human skin is the first organ exposed to various environmental stresses, which requires the development by skin stem cells of specific mechanisms to protect themselves and to ensure tissue homeostasis. As stem cells are responsible for the maintenance of epidermis during individual lifetime, the preservation of genomic integrity in these cells is essential. My PhD aimed at exploring the mechanisms set up by epidermal stem cells in order to protect themselves from two genotoxic stresses, ionizing radiation (Gamma Rays) and ultraviolet radiation (UVB). To begin my PhD, I have taken part of the demonstration of protective mechanisms used by keratinocyte stem cells after ionizing radiation. It has been shown that these cells are able to rapidly repair most types of radiation-induced DNA damage. Furthermore, we demonstrated that this repair is activated by the fibroblast growth factor 2 (FGF2). In order to know if this protective mechanism is also operating in cutaneous carcinoma stem cells, we investigated the response to gamma Rays of carcinoma stem cells isolated from a human carcinoma cell line. As in normal keratinocyte stem cells, we demonstrated that cancer stem cells could rapidly repair radio-induced DNA damage. Furthermore, fibroblast growth factor 2 also mediates this repair, notably thanks to its nuclear isoforms. The second project of my PhD was to study human epidermal stem cells and progenitors responses to UVB radiation. Once cytometry and irradiation conditions were set up, the toxicity of UVB radiation has been evaluate in the primary cell model. We then characterized UVB photons effects on cell viability, proliferation and repair of DNA damage. This study allowed us to bring out that responses of stem cells and their progeny to UVB are different, notably at the level of part of their repair activity of DNA damage. Moreover, progenitors and stem cells transcriptomic responses after UVB irradiation have been study in order to analyze the global

Diploid, but not haploid, human embryonic stem cells can be derived from microsurgically repaired tripronuclear human zygotes

Science.gov (United States)

Fan, Yong; Li, Rong; Huang, Jin; Yu, Yang; Qiao, Jie

2013-01-01

Human embryonic stem cells have shown tremendous potential in regenerative medicine, and the recent progress in haploid embryonic stem cells provides new insights for future applications of embryonic stem cells. Disruption of normal fertilized embryos remains controversial; thus, the development of a new source for human embryonic stem cells is important for their usefulness. Here, we investigated the feasibility of haploid and diploid embryo reconstruction and embryonic stem cell derivation using microsurgically repaired tripronuclear human zygotes. Diploid and haploid zygotes were successfully reconstructed, but a large proportion of them still had a tripolar spindle assembly. The reconstructed embryos developed to the blastocyst stage, although the loss of chromosomes was observed in these zygotes. Finally, triploid and diploid human embryonic stem cells were derived from tripronuclear and reconstructed zygotes (from which only one pronucleus was removed), but haploid human embryonic stem cells were not successfully derived from the reconstructed zygotes when two pronuclei were removed. Both triploid and diploid human embryonic stem cells showed the general characteristics of human embryonic stem cells. These results indicate that the lower embryo quality resulting from abnormal spindle assembly contributed to the failure of the haploid embryonic stem cell derivation. However, the successful derivation of diploid embryonic stem cells demonstrated that microsurgical tripronuclear zygotes are an alternative source of human embryonic stem cells. In the future, improving spindle assembly will facilitate the application of triploid zygotes to the field of haploid embryonic stem cells. PMID:23255130

Mouse embryonic stem cells, but not somatic cells, predominantly use homologous recombination to repair double-strand DNA breaks.

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Tichy, Elisia D; Pillai, Resmi; Deng, Li; Liang, Li; Tischfield, Jay; Schwemberger, Sandy J; Babcock, George F; Stambrook, Peter J

2010-11-01

Embryonic stem (ES) cells give rise to all cell types of an organism. Since mutations at this embryonic stage would affect all cells and be detrimental to the overall health of an organism, robust mechanisms must exist to ensure that genomic integrity is maintained. To test this proposition, we compared the capacity of murine ES cells to repair DNA double-strand breaks with that of differentiated cells. Of the 2 major pathways that repair double-strand breaks, error-prone nonhomologous end joining (NHEJ) predominated in mouse embryonic fibroblasts, whereas the high fidelity homologous recombinational repair (HRR) predominated in ES cells. Microhomology-mediated end joining, an emerging repair pathway, persisted at low levels in all cell types examined. The levels of proteins involved in HRR and microhomology-mediated end joining were highly elevated in ES cells compared with mouse embryonic fibroblasts, whereas those for NHEJ were quite variable, with DNA Ligase IV expression low in ES cells. The half-life of DNA Ligase IV protein was also low in ES cells. Attempts to increase the abundance of DNA Ligase IV protein by overexpression or inhibition of its degradation, and thereby elevate NHEJ in ES cells, were unsuccessful. When ES cells were induced to differentiate, however, the level of DNA Ligase IV protein increased, as did the capacity to repair by NHEJ. The data suggest that preferential use of HRR rather than NHEJ may lend ES cells an additional layer of genomic protection and that the limited levels of DNA Ligase IV may account for the low level of NHEJ activity.

Repair of Ischemic Injury by Pluripotent Stem Cell Based Cell Therapy without Teratoma through Selective Photosensitivity

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Seung-Ju Cho

2015-12-01

Full Text Available Stem-toxic small molecules have been developed to induce selective cell death of pluripotent stem cells (PSCs to lower the risk of teratoma formation. However, despite their high efficacies, chemical-based approaches may carry unexpected toxicities on specific differentiated cell types. Herein, we took advantage of KillerRed (KR as a suicide gene, to selectively induce phototoxicity using visible light via the production of reactive oxygen species. PSCs in an undifferentiated state that exclusively expressed KR (KR-PSCs were eliminated by a single exposure to visible light. This highly selective cell death in KR-PSCs was exploited to successfully inhibit teratoma formation. In particular, endothelial cells from KR-mPSCs remained fully functional in vitro and sufficient to repair ischemic injury in vivo regardless of light exposure, suggesting that a genetic approach in which KR is expressed in a tightly controlled manner would be a viable strategy to inhibit teratoma formation for future safe PSC-based therapies.

Reserve stem cells: Reprogramming of differentiated cells fuels repair, metaplasia, and neoplasia in the adult gastrointestinal tract

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Mills, Jason C.; Sansom, Owen J.

2016-01-01

It has long been known that differentiated cells can switch fates, especially in vitro, but only recently has there been a critical mass of publications describing the mechanisms adult, post-mitotic cells use in vivo to reverse their differentiation state. We propose that this sort of cellular reprogramming is a fundamental cellular process akin to apoptosis or mitosis. Because reprogramming can invoke regenerative cells from mature cells, it is critical to the longterm maintenance of tissues like the pancreas, which encounter large insults during adulthood but lack constitutively active adult stem cells to repair the damage. However, even in tissues with adult stem cells, like stomach and intestine, reprogramming may allow mature cells to serve as reserve (“quiescent”) stem cells when normal stem cells are compromised. We propose that the potential downside to reprogramming is that it increases risk for cancers that occur late in adulthood. Mature, long-lived cells may have years of exposure to mutagens. Mutations that affect the physiological function of differentiated, post-mitotic cells may lead to apoptosis, but mutations in genes that govern proliferation might not be selected against. Hence, reprogramming with reentry into the cell cycle might unmask those mutations, causing an irreversible progenitor-like, proliferative state. We review recent evidence showing that reprogramming fuels irreversible metaplastic and precancerous proliferations in stomach and pancreas. Finally, we illustrate how we think reprogrammed differentiated cells are likely candidates as cells of origin for cancers of the intestine. PMID:26175494

Adult Stem Cell Based Enhancement of Nerve Conduit for Peripheral Nerve Repair

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2016-10-01

accompanied by injuries to peripheral nerves; if not repaired, the trauma can lead to significant dysfunction and disability . While nerves have the ability to...recovery, minimized disability , and increased quality of life for our wounded warriors. 2. KEYWORDS: Stem Cell, Nerve Conduit, Peripheral Nerve...would be a paradigm shift away from ordering X-rays at 10-12 weeks and only ordering a CT scan. It has the potential to change the standard of care

[Progress in epidermal stem cells].

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Wang, Li-Juan; Wang, You-Liang; Yang, Xiao

2010-03-01

Mammalian skin epidermis contains different epidermal stem cell pools which contribute to the homeostasis and repair of skin epithelium. Epidermal stem cells possess two essential features common to all stem cells: self-renewal and differentiation. Disturbing the balance between self-renewal and differentiation of epidermal stem cell often causes tumors or other skin diseases. Epidermal stem cell niches provide a special microenvironment that maintains a balance of stem cell quiescence and activity. This review primarily concentrates on the following points of the epidermal stem cells: the existing evidences, the self-renewal and differentiation, the division pattern, the signal pathways regulating self-renewal and differentiation, and the microenvironment (niche) and macroenvironment maintaining the homeostasis of stem cells.

Repair of full-thickness articular cartilage defect using stem cell-encapsulated thermogel.

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Zhang, Yanbo; Zhang, Jin; Chang, Fei; Xu, Weiguo; Ding, Jianxun

2018-07-01

Cartilage defect repair by hydrogel-based tissue engineering is becoming one of the most potential treatment strategies. In this work, a thermogel of triblock copolymer poly(lactide-co-glycolide)-block-poly(ethylene glycol)-block-poly(lactide-co-glycolide) (PLGA-PEG-PLGA) was prepared as scaffold of bone marrow mesenchymal stem cells (BMMSCs) for repair of full-thickness articular cartilage defect. At first, the copolymer solution showed a reversible sol-gel transition at physiological temperature range, and the mechanical properties of such thermogel were high enough to support the repair of cartilage. Additionally, excellent biodegradability and biocompatibility of the thermogel were demonstrated. By implanting the BMMSC-encapsulated thermogel into the full-thickness articular cartilage defect (5.0 mm in diameter and 4.0 mm in depth) in the rabbit, it was found that the regenerated cartilage integrated well with the surrounding normal cartilage and subchondral bone at 12 weeks post-surgery. The upregulated expression of glycosaminoglycan and type II collagen in the repaired cartilage, and the comparable biomechanical properties with normal cartilage suggested that the cell-encapsulated PLGA-PEG-PLGA thermogel had great potential in serving as the promising scaffold for cartilage regeneration. Copyright © 2018 Elsevier B.V. All rights reserved.

Human umbilical cord mesenchymal stem cells promote peripheral nerve repair via paracrine mechanisms

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Zhi-yuan Guo

2015-01-01

Full Text Available Human umbilical cord-derived mesenchymal stem cells (hUCMSCs represent a promising young-state stem cell source for cell-based therapy. hUCMSC transplantation into the transected sciatic nerve promotes axonal regeneration and functional recovery. To further clarify the paracrine effects of hUCMSCs on nerve regeneration, we performed human cytokine antibody array analysis, which revealed that hUCMSCs express 14 important neurotrophic factors. Enzyme-linked immunosorbent assay and immunohistochemistry showed that brain-derived neurotrophic factor, glial-derived neurotrophic factor, hepatocyte growth factor, neurotrophin-3, basic fibroblast growth factor, type I collagen, fibronectin and laminin were highly expressed. Treatment with hUCMSC-conditioned medium enhanced Schwann cell viability and proliferation, increased nerve growth factor and brain-derived neurotrophic factor expression in Schwann cells, and enhanced neurite growth from dorsal root ganglion explants. These findings suggest that paracrine action may be a key mechanism underlying the effects of hUCMSCs in peripheral nerve repair.

Bone repair by periodontal ligament stem cell-seeded nanohydroxyapatite-chitosan scaffold

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Ge S

2012-10-01

Full Text Available Shaohua Ge,1 Ning Zhao,1 Lu Wang,1 Meijiao Yu,1 Hong Liu,2 Aimei Song,1 Jing Huang,1 Guancong Wang,2 Pishan Yang11Key Laboratory of Oral Biomedicine of Shandong Province, Department of Periodontology, School of Stomatology, 2Center of Bio and Micro/Nano Functional Materials, State Key Laboratory of Crystal Materials, Shandong University, Jinan, ChinaBackground: A nanohydroxyapatite-coated chitosan scaffold has been developed in recent years, but the effect of this composite scaffold on the viability and differentiation of periodontal ligament stem cells (PDLSCs and bone repair is still unknown. This study explored the behavior of PDLSCs on a new nanohydroxyapatite-coated genipin-chitosan conjunction scaffold (HGCCS in vitro as compared with an uncoated genipin-chitosan framework, and evaluated the effect of PDLSC-seeded HGCCS on bone repair in vivo.Methods: Human PDLSCs were cultured and identified, seeded on a HGCCS and on a genipin-chitosan framework, and assessed by scanning electron microscopy, confocal laser scanning microscopy, MTT, alkaline phosphatase activity, and quantitative real-time polymerase chain reaction at different time intervals. Moreover, PDLSC-seeded scaffolds were used in a rat calvarial defect model, and new bone formation was assessed by hematoxylin and eosin staining at 12 weeks postoperatively.Results: PDLSCs were clonogenic and positive for STRO-1. They had the capacity to undergo osteogenic and adipogenic differentiation in vitro. When seeded on HGCCS, PDLSCs exhibited significantly greater viability, alkaline phosphatase activity, and upregulated the bone-related markers, bone sialoprotein, osteopontin, and osteocalcin to a greater extent compared with PDLSCs seeded on the genipin-chitosan framework. The use of PDLSC-seeded HGCCS promoted calvarial bone repair.Conclusion: This study demonstrates the potential of HGCCS combined with PDLSCs as a promising tool for bone regeneration.Keywords: periodontal ligament, stem

The Role of Recipient T Cells in Mesenchymal Stem Cell-Based Tissue Regeneration

OpenAIRE

Liu, Yi; Wang, Songlin; Shi, Songtao

2012-01-01

Significant progress has been made in stem cell biology, regenerative medicine, and stem cell-based tissue engineering. Such scientific strides highlight the potential of replacing or repairing damaged tissues in congenital abnormalities, diseases, or injuries, as well as constructing functional tissue or organs in vivo. Since mesenchymal stem cells (MSCs) are capable of differentiating into bone-forming cells, they constitute an appropriate cell source to repair damaged bone tissues. In addi...

Adipose stem cells for bone tissue repair

OpenAIRE

Ciuffi, Simone; Zonefrati, Roberto; Brandi, Maria Luisa

2017-01-01

Adipose-derived stem/stromal cells (ASCs), together with adipocytes, vascular endothelial cells, and vascular smooth muscle cells, are contained in fat tissue. ASCs, like the human bone marrow stromal/stem cells (BMSCs), can differentiate into several lineages (adipose cells, fibroblast, chondrocytes, osteoblasts, neuronal cells, endothelial cells, myocytes, and cardiomyocytes). They have also been shown to be immunoprivileged, and genetically stable in long-term cultures. Nevertheless, unlik...

Reserve stem cells: Differentiated cells reprogram to fuel repair, metaplasia, and neoplasia in the adult gastrointestinal tract.

Science.gov (United States)

Mills, Jason C; Sansom, Owen J

2015-07-14

It has long been known that differentiated cells can switch fates, especially in vitro, but only recently has there been a critical mass of publications describing the mechanisms adult, postmitotic cells use in vivo to reverse their differentiation state. We propose that this sort of cellular reprogramming is a fundamental cellular process akin to apoptosis or mitosis. Because reprogramming can invoke regenerative cells from mature cells, it is critical to the long-term maintenance of tissues like the pancreas, which encounter large insults during adulthood but lack constitutively active adult stem cells to repair the damage. However, even in tissues with adult stem cells, like the stomach and intestine, reprogramming may allow mature cells to serve as reserve ("quiescent") stem cells when normal stem cells are compromised. We propose that the potential downside to reprogramming is that it increases risk for cancers that occur late in adulthood. Mature, long-lived cells may have years of exposure to mutagens. Mutations that affect the physiological function of differentiated, postmitotic cells may lead to apoptosis, but mutations in genes that govern proliferation might not be selected against. Hence, reprogramming with reentry into the cell cycle might unmask those mutations, causing an irreversible progenitor-like, proliferative state. We review recent evidence showing that reprogramming fuels irreversible metaplastic and precancerous proliferation in the stomach and pancreas. Finally, we illustrate how we think reprogrammed differentiated cells are likely candidates as cells of origin for cancers of the intestine. Copyright © 2015, American Association for the Advancement of Science.

Current status of stem cells in cardiac repair.

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Henning, Robert J

2018-03-01

One out of every two men and one out of every three women greater than the age of 40 will experience an acute myocardial infarction (AMI) at some time during their lifetime. As more patients survive their AMIs, the incidence of congestive heart failure (CHF) is increasing. 6 million people in the USA have ischemic cardiomyopathies and CHF. The search for new and innovative treatments for patients with AMI and CHF has led to investigations and use of human embryonic stem cells, cardiac stem/progenitor cells, bone marrow-derived mononuclear cells and mesenchymal stem cells for treatment of these heart conditions. This paper reviews current investigations with human embryonic, cardiac, bone marrow and mesenchymal stem cells, and also stem cell paracrine factors and exosomes.

Loss of DNA mismatch repair imparts a selective advantage in planarian adult stem cells.

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Jessica P Hollenbach

Full Text Available Lynch syndrome (LS leads to an increased risk of early-onset colorectal and other types of cancer and is caused by germline mutations in DNA mismatch repair (MMR genes. Loss of MMR function results in a mutator phenotype that likely underlies its role in tumorigenesis. However, loss of MMR also results in the elimination of a DNA damage-induced checkpoint/apoptosis activation barrier that may allow damaged cells to grow unchecked. A fundamental question is whether loss of MMR provides pre-cancerous stem cells an immediate selective advantage in addition to establishing a mutator phenotype. To test this hypothesis in an in vivo system, we utilized the planarian Schmidtea mediterranea which contains a significant population of identifiable adult stem cells. We identified a planarian homolog of human MSH2, a MMR gene which is mutated in 38% of LS cases. The planarian Smed-msh2 is expressed in stem cells and some progeny. We depleted Smed-msh2 mRNA levels by RNA-interference and found a striking survival advantage in these animals treated with a cytotoxic DNA alkylating agent compared to control animals. We demonstrated that this tolerance to DNA damage is due to the survival of mitotically active, MMR-deficient stem cells. Our results suggest that loss of MMR provides an in vivo survival advantage to the stem cell population in the presence of DNA damage that may have implications for tumorigenesis.

Effects of cell-to-collagen ratio in stem cell-seeded constructs for Achilles tendon repair.

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Juncosa-Melvin, Natalia; Boivin, Gregory P; Galloway, Marc T; Gooch, Cindi; West, John R; Butler, David L

2006-04-01

The objective of the present study was to test the hypotheses that implantation of cell-seeded constructs in a rabbit Achilles tendon defect model would 1) improve repair biomechanics and matrix organization and 2) result in higher failure forces than measured in vivo forces in normal rabbit Achilles tendon (AT) during an inclined hopping activity. Autogenous tissue-engineered constructs were fabricated in culture between posts in the wells of silicone dishes at four cell-to-collagen ratios by seeding mesenchymal stem cells (MSC) from 18 adult rabbits at each of two seeding densities (0.1 x 10(6) and 1 x 10(6) cell/mL) in each of two collagen concentrations (1.3 and 2.6 mg/mL). After 5 days of contraction, constructs having the two highest ratios (0.4 and 0.8 M/mg) were damaged by excessive cell traction forces and could not be used in subsequent in vivo studies. Constructs at the lower ratios (0.04 and 0.08 M/mg) were implanted in bilateral, 2 cm long gap defects in the rabbit's lateral Achilles tendon. At 12 weeks after surgery, both repair tissues were isolated and either failed in tension (n = 13) to determine their biomechanical properties or submitted for histological analysis (n = 5). No significant differences were observed in any structural or mechanical properties or in histological appearance between the two repair conditions. However, the average maximum force and maximum stress of these repairs achieved 50 and 85% of corresponding values for the normal AT and exceeded the largest peak in vivo forces (19% of failure) previously recorded in the rabbit AT. Average stiffness and modulus were 60 and 85% of normal values, respectively. New constructs with lower cell densities and higher scaffold stiffness that do not excessively contract and tear in culture and that further improve the repair stiffness needed to withstand various levels of expected in vivo loading are currently being investigated.

Translational findings from cardiovascular stem cell research.

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Mazhari, Ramesh; Hare, Joshua M

2012-01-01

The possibility of using stem cells to regenerate damaged myocardium has been actively investigated since the late 1990s. Consistent with the traditional view that the heart is a "postmitotic" organ that possesses minimal capacity for self-repair, much of the preclinical and clinical work has focused exclusively on introducing stem cells into the heart, with the hope of differentiation of these cells into functioning cardiomyocytes. This approach is ongoing and retains promise but to date has yielded inconsistent successes. More recently, it has become widely appreciated that the heart possesses endogenous repair mechanisms that, if adequately stimulated, might regenerate damaged cardiac tissue from in situ cardiac stem cells. Accordingly, much recent work has focused on engaging and enhancing endogenous cardiac repair mechanisms. This article reviews the literature on stem cell-based myocardial regeneration, placing emphasis on the mutually enriching interaction between basic and clinical research. Copyright © 2012 Elsevier Inc. All rights reserved.

Stem Cells and Aging.

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Koliakos, George

2017-02-01

The article is a presentation at the 4th Conference of ESAAM, which took place on October 30-31, 2015, in Athens, Greece. Its purpose was not to cover all aspects of cellular aging but to share with the audience of the Conference, in a 15-minute presentation, current knowledge about the rejuvenating and repairing somatic stem cells that are distinct from other stem cell types (such as embryonic or induced pluripotent stem cells), emphasize that our body in old age cannot take advantage of these rejuvenating cells, and provide some examples of novel experimental stem cell applications in the field of rejuvenation and antiaging biomedical research.

Hematopoietic stem cells : Self-renewing or aging?

NARCIS (Netherlands)

de Haan, G

2002-01-01

Stem cells are defined by their extensive self-renewal properties, and yet there is abundant evidence of erosion of stem cell functioning during aging. Whereas intracellular repair and protection mechanisms determine the lifespan of an individual cell, here an argument is made that somatic stem

Dental Stem Cell in Tooth Development and Advances of Adult Dental Stem Cell in Regenerative Therapies.

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Tan, Jiali; Xu, Xin; Lin, Jiong; Fan, Li; Zheng, Yuting; Kuang, Wei

2015-01-01

Stem cell-based therapies are considered as a promising treatment for many clinical usage such as tooth regeneration, bone repairation, spinal cord injury, and so on. However, the ideal stem cell for stem cell-based therapy still remains to be elucidated. In the past decades, several types of stem cells have been isolated from teeth, including dental pulp stem cells (DPSCs), stem cells from human exfoliated deciduous teeth (SHED), periodontal ligament stem cells (PDLSCs), dental follicle progenitor stem cells (DFPCs) and stem cells from apical papilla (SCAP), which may be a good source for stem cell-based therapy in certain disease, especially when they origin from neural crest is considered. In this review, the specific characteristics and advantages of the adult dental stem cell population will be summarized and the molecular mechanisms of the differentiation of dental stem cell during tooth development will be also discussed.

Electrical Stimulation Elicit Neural Stem Cells Activation：New Perspectives in CNS Repair

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Ratrel eHuang

2015-10-01

Full Text Available Researchers are enthusiastically concerned about neural stem cell (NSC therapy in a wide array of diseases, including stroke, neurodegenerative disease, spinal cord injury (SCI and depression. Although enormous evidences have demonstrated that neurobehavioral improvement may benefit from NSC-supporting regeneration in animal models, approaches to endogenous and transplanted NSCs are blocked by hurdles of migration, proliferation, maturation and integration of NSCs. Electrical stimulation (ES may be a selective nondrug approach for mobilizing NSCs in the central nervous system (CNS. This technique is suitable for clinic application, because it is well established and its potential complications are manageable. Here, we provide a comprehensive review of the emerging positive role of different electrical cues in regulating NSC biology in vitro and in vivo, as well as biomaterial-based and chemical stimulation of NSCs. In the future, ES combined with stem cell therapy or other cues probably becomes an approach for promoting brain repair.

Endogenous repair mechanisms enhanced in Parkinson's disease following stem cell therapy

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Eleonora Napoli

2017-01-01

Full Text Available This mini-review highlights the innovative observation that transplanted human neural stem cells can bring about endogenous brain repair through the stimulation of multiple regenerative processes in the neurogenic area (i.e., subventricular zone [SVZ] in an animal model of Parkinson's disease (PD. In addition, we convey that identifying anti-inflammatory cytokines, therapeutic proteomes, and neurotrophic factors within the SVZ may be essential to induce brain repair and behavioral recovery. This work opens up a new area of research for further understanding the pathology and treatment of PD. This paper is a review article. Referred literature in this paper has been listed in the references section. The datasets supporting the conclusions of this article are available online by searching various databases, including PubMed. Some original points in this article come from the laboratory practice in our research center and the authors' experiences.

A Systematic Review of Mesenchymal Stem Cells in Spinal Cord Injury, Intervertebral Disc Repair and Spinal Fusion.

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Khan, Shujhat; Mafi, Pouya; Mafi, Reza; Khan, Wasim

2018-01-01

Spinal surgery presents a challenge for both neurosurgery and orthopaedic surgery. Due to the heterogeneous differentiation potential of mesenchymal stem cells, there is much interest in the treatment of spine surgery. Animal and human trials focussing on the efficacy of mesenchymal stem cells in spinal cord injury, spine fusion and disc degeneration were included in this systematic review. Published articles up to January 2016 from MEDLINE, PubMed and Ovid were used by searching for specific terms. Of the 2595 articles found, 53 met the selection criteria and were included for analysis (16 on spinal cord injury, 28 on intervertebral disc repair and 9 on spinal fusion). Numerous studies reported better results when the mesenchymal stem cells were used in co-culture with other cells or used in scaffolds. Mesenchymal stem cells were also found to have an immune-modulatory role, which can improve surgical outcome. This systematic review suggests that mesenchymal stem cells can be used safely and effectively for these spinal surgery treatments. Whilst, in certain studies, mesenchymal stem cells did not necessarily show improved results from existing treatments, they provide an alternative option. This can reduce morbidity that arises from current surgical treatment. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Tissue-specific designs of stem cell hierarchies

NARCIS (Netherlands)

Visvader, Jane E.; Clevers, Hans

2016-01-01

Recent work in the field of stem cell biology suggests that there is no single design for an adult tissue stem cell hierarchy, and that different tissues employ distinct strategies to meet their self-renewal and repair requirements. Stem cells may be multipotent or unipotent, and can exist in

Tissue-specific designs of stem cell hierarchies

NARCIS (Netherlands)

Visvader, Jane E; Clevers, Hans

Recent work in the field of stem cell biology suggests that there is no single design for an adult tissue stem cell hierarchy, and that different tissues employ distinct strategies to meet their self-renewal and repair requirements. Stem cells may be multipotent or unipotent, and can exist in

Enrichment of G2/M cell cycle phase in human pluripotent stem cells enhances HDR-mediated gene repair with customizable endonucleases.

Science.gov (United States)

Yang, Diane; Scavuzzo, Marissa A; Chmielowiec, Jolanta; Sharp, Robert; Bajic, Aleksandar; Borowiak, Malgorzata

2016-02-18

Efficient gene editing is essential to fully utilize human pluripotent stem cells (hPSCs) in regenerative medicine. Custom endonuclease-based gene targeting involves two mechanisms of DNA repair: homology directed repair (HDR) and non-homologous end joining (NHEJ). HDR is the preferred mechanism for common applications such knock-in, knock-out or precise mutagenesis, but remains inefficient in hPSCs. Here, we demonstrate that synchronizing synchronizing hPSCs in G2/M with ABT phase increases on-target gene editing, defined as correct targeting cassette integration, 3 to 6 fold. We observed improved efficiency using ZFNs, TALENs, two CRISPR/Cas9, and CRISPR/Cas9 nickase to target five genes in three hPSC lines: three human embryonic stem cell lines, neural progenitors and diabetic iPSCs. neural progenitors and diabetic iPSCs. Reversible synchronization has no effect on pluripotency or differentiation. The increase in on-target gene editing is locus-independent and specific to the cell cycle phase as G2/M phase enriched cells show a 6-fold increase in targeting efficiency compared to cells in G1 phase. Concurrently inhibiting NHEJ with SCR7 does not increase HDR or improve gene targeting efficiency further, indicating that HR is the major DNA repair mechanism after G2/M phase arrest. The approach outlined here makes gene editing in hPSCs a more viable tool for disease modeling, regenerative medicine and cell-based therapies.

Modulating the stem cell niche for tissue regeneration

Science.gov (United States)

Lane, Steven W; Williams, David A; Watt, Fiona M

2015-01-01

The field of regenerative medicine holds considerable promise for treating diseases that are currently intractable. Although many researchers are adopting the strategy of cell transplantation for tissue repair, an alternative approach to therapy is to manipulate the stem cell microenvironment, or niche, to facilitate repair by endogenous stem cells. The niche is highly dynamic, with multiple opportunities for intervention. These include administration of small molecules, biologics or biomaterials that target specific aspects of the niche, such as cell-cell and cell–extracellular matrix interactions, to stimulate expansion or differentiation of stem cells, or to cause reversion of differentiated cells to stem cells. Nevertheless, there are several challenges in targeting the niche therapeutically, not least that of achieving specificity of delivery and responses. We envisage that successful treatments in regenerative medicine will involve different combinations of factors to target stem cells and niche cells, applied at different times to effect recovery according to the dynamics of stem cell–niche interactions. PMID:25093887

Brain mesenchymal stem cells: The other stem cells of the brain?

Science.gov (United States)

Appaix, Florence; Nissou, Marie-France; van der Sanden, Boudewijn; Dreyfus, Matthieu; Berger, François; Issartel, Jean-Paul; Wion, Didier

2014-04-26

Multipotent mesenchymal stromal cells (MSC), have the potential to differentiate into cells of the mesenchymal lineage and have non-progenitor functions including immunomodulation. The demonstration that MSCs are perivascular cells found in almost all adult tissues raises fascinating perspectives on their role in tissue maintenance and repair. However, some controversies about the physiological role of the perivascular MSCs residing outside the bone marrow and on their therapeutic potential in regenerative medicine exist. In brain, perivascular MSCs like pericytes and adventitial cells, could constitute another stem cell population distinct to the neural stem cell pool. The demonstration of the neuronal potential of MSCs requires stringent criteria including morphological changes, the demonstration of neural biomarkers expression, electrophysiological recordings, and the absence of cell fusion. The recent finding that brain cancer stem cells can transdifferentiate into pericytes is another facet of the plasticity of these cells. It suggests that the perversion of the stem cell potential of pericytes might play an even unsuspected role in cancer formation and tumor progression.

Stem cell-based approaches in dentistry

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TA Mitsiadis

2011-11-01

Full Text Available Repair of dental pulp and periodontal lesions remains a major clinical challenge. Classical dental treatments require the use of specialised tissue-adapted materials with still questionable efficacy and durability. Stem cell-based therapeutic approaches could offer an attractive alternative in dentistry since they can promise physiologically improved structural and functional outcomes. These therapies necessitate a sufficient number of specific stem cell populations for implantation. Dental mesenchymal stem cells can be easily isolated and are amenable to in vitro expansion while retaining their stemness. In vivo studies realised in small and large animals have evidenced the potential of dental mesenchymal stem cells to promote pulp and periodontal regeneration, but have also underlined new important challenges. The homogeneity of stem cell populations and their quality control, the delivery method, the quality of the regenerated dental tissues and their integration to the host tissue are some of the key challenges. The use of bioactive scaffolds that can elicit effective tissue repair response, through activation and mobilisation of endogenous stem cell populations, constitutes another emerging therapeutic strategy. Finally, the use of stem cells and induced pluripotent cells for the regeneration of entire teeth represents a novel promising alternative to dental implant treatment after tooth loss. In this mini-review, we present the currently applied techniques in restorative dentistry and the various attempts that are made to bridge gaps in knowledge regarding treatment strategies by translating basic stem cell research into the dental practice.

Mesenchymal Stem Cells as a Potent Cell Source for Bone Regeneration

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Elham Zomorodian

2012-01-01

Full Text Available While small bone defects heal spontaneously, large bone defects need surgical intervention for bone transplantation. Autologous bone grafts are the best and safest strategy for bone repair. An alternative method is to use allogenic bone graft. Both methods have limitations, particularly when bone defects are of a critical size. In these cases, bone constructs created by tissue engineering technologies are of utmost importance. Cells are one main component in the manufacture of bone construct. A few cell types, including embryonic stem cells (ESCs, adult osteoblast, and adult stem cells, can be used for this purpose. Mesenchymal stem cells (MSCs, as adult stem cells, possess characteristics that make them good candidate for bone repair. This paper discusses different aspects of MSCs that render them an appropriate cell type for clinical use to promote bone regeneration.

Stem cells in endodontic therapy

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Sita Rama Kumar M, Madhu Varma K, Kalyan Satish R, Manikya kumar Nanduri.R, Murali Krishnam Raju S, Mohan rao

2014-11-01

Full Text Available Stem cells have the remarkable potential to develop into many different cell types in the body. Serving as a sort of repair system for the body, they can theoretically divide without limit to replenish other cells as long as the person or animal is still alive. However, progress in stem cell biology and tissue engineering may present new options for replacing heavily damaged or lost teeth, or even individual tooth structures. The goal of this review is to discuss the potential impact of dental pulp stem cells on regenerative endodontics.

Perivascular Mesenchymal Stem Cells in Sheep: Characterization and Autologous Transplantation in a Model of Articular Cartilage Repair.

Science.gov (United States)

Hindle, Paul; Baily, James; Khan, Nusrat; Biant, Leela C; Simpson, A Hamish R; Péault, Bruno

2016-11-01

Previous research has indicated that purified perivascular stem cells (PSCs) have increased chondrogenic potential compared to conventional mesenchymal stem cells (MSCs) derived in culture. This study aimed to develop an autologous large animal model for PSC transplantation and to specifically determine if implanted cells are retained in articular cartilage defects. Immunohistochemistry and fluorescence-activated cell sorting were used to ascertain the reactivity of anti-human and anti-ovine antibodies, which were combined and used to identify and isolate pericytes (CD34 - CD45 - CD146 + ) and adventitial cells (CD34 + CD45 - CD146 - ). The purified cells demonstrated osteogenic, adipogenic, and chondrogenic potential in culture. Autologous ovine PSCs (oPSCs) were isolated, cultured, and efficiently transfected using a green fluorescence protein (GFP) encoding lentivirus. The cells were implanted into articular cartilage defects on the medial femoral condyle using hydrogel and collagen membranes. Four weeks following implantation, the condyle was explanted and confocal laser scanning microscopy demonstrated the presence of oPSCs in the defect repaired with the hydrogel. These data suggest the testability in a large animal of native MSC autologous grafting, thus avoiding possible biases associated with xenotransplantation. Such a setting will be used in priority for indications in orthopedics, at first to model articular cartilage repair.

Osteochondral defect repair using bilayered hydrogels encapsulating both chondrogenically and osteogenically pre-differentiated mesenchymal stem cells in a rabbit model

NARCIS (Netherlands)

Lam, J.; Lu, S.; Lee, E.J.; Trachtenberg, J.E.; Meretoja, V.V.; Dahlin, R.L.; van den Beucken, J.J.; Tabata, Y.; Wong, M.E.; Jansen, J.A.; Mikos, A.G.; Kasper, F.K.

2014-01-01

OBJECTIVE: To investigate the ability of cell-laden bilayered hydrogels encapsulating chondrogenically and osteogenically (OS) pre-differentiated mesenchymal stem cells (MSCs) to effect osteochondral defect repair in a rabbit model. By varying the period of chondrogenic pre-differentiation from 7

Mesenchymal Stem Cells

DEFF Research Database (Denmark)

Horwood, Nicole J.; Dazzi, Francesco; Zaher, Walid

2012-01-01

Mesenchymal stem cells (MSC) are stem cell populations present among the bone marrow stroma and a number of other tissues that are capable of multi-lineage differentiation into mesoderm-type cells such as osteoblasts, adipocytes and chondrocytes. MSC provide supportive stroma for growth...... and differentiation of hematopoietic stem cells (HSC) and hematopoiesis. These cells have been described as important immunoregulators due to their ability to suppress T cells proliferation. MSC can also directly contribute to tissue repair by migrating to sites of injury and providing a source of cells...... for differentiation and/or providing bystander support for resident stromal cells. This chapter discusses the cellular and molecular properties of MSC, the mechanisms by which they can modulate immune responses and the clinical applications of MSC in disorders such as graft-versus-host disease and aplastic anaemia...

Mesenchymal Stem Cells in Cardiology

Science.gov (United States)

White, Ian A.; Sanina, Cristina; Balkan, Wayne; Hare, Joshua M.

2017-01-01

Cardiovascular disease (CVD) accounts for more deaths globally than any other single disease. There are on average 1.5 million episodes of myocardial infarction (heart attack) each year in the United States alone with roughly one third resulting in death. There is therefore a major need for developing new and effective strategies to promote cardiac repair. Intramyocardial transplantation of mesenchymal stem cells (MSCs) has emerged as a leading contender in the pursuit of clinical intervention and therapy. MSCs are potent mediators of cardiac repair and are therefore an attractive tool in the development of pre-clinical and clinical trials. MSCs are capable of secreting a large array of soluble factors, which have had demonstrated effects on pathogenic cardiac remolding, fibrosis, immune activation and cardiac stem cell proliferation within the damaged heart. MSCs are also capable of differentiation into cardiomyocytes, endothelial cells and vascular smooth muscle cells, although the relative contribution of trilineage differentiation and paracrine effectors on cardiac repair remains the subject of active investigation. PMID:27236666

Evaluation of phototherapy in the differentiation of mesenchymal stem cells in the tissue repair of rats submitted to a hyperlipidemic diet

Science.gov (United States)

Oliveira, C. R. B.; Santos, L. S.; Silva, V. D. U.; Vitória, L. A.; Rodriguez, T. T.; Marques, A. M. C.; Xavier, F. C. A.; Ramalho, L.

2018-04-01

Obese people present a greater risk of developing other systemic diseases and comorbidities such as compromising the tissue repair process. Laser phototherapy can contribute to this repair by improving cellular functions, since stem cells may play an important role in repair due to their pluripotent potential. In this way, the influence of Laser Phototherapy (LP) was evaluated in the tissue repair of rats submitted to a hyperlipid diet through CD49 immunostaining for adipose stem cells. Forty-eight Wistar albinus rats were divided into two experimental groups: Standard Diet (SD) and Hyperlipid Diet (HD) for 20 weeks. After this period, excisional dorsal cutaneous wounds of 1 cm2 were made. The groups were subdivided into control and laser, the laser groups were irradiated (Diode Laser of Gallium and Aluminum Arsenide, λ660nm, 40mW, 6J / cm2) immediately after the surgery and every 48 hours. A group of rats were killed on day 7 and the other group on day 14 and the specimens processed by the immunohistochemical technique. The SD group presented antibodies marked with moderate to intense intensity, whereas in the HD group the weak staining for the time of 14 days prevailed. The irradiation protocol employed had no influence on the CD49 marker when compared to the control and irradiated groups over the same period. According to the methodology used and the results obtained it is concluded that laser light does not influence the recruitment of adipoderivative stem cells for the tissue repair process.

Chondroitinase ABC plus bone marrow mesenchymal stem cells for repair of spinal cord injury☆

Science.gov (United States)

Zhang, Chun; He, Xijing; Li, Haopeng; Wang, Guoyu

2013-01-01

As chondroitinase ABC can improve the hostile microenvironment and cell transplantation is proven to be effective after spinal cord injury, we hypothesized that their combination would be a more effective treatment option. At 5 days after T8 spinal cord crush injury, rats were injected with bone marrow mesenchymal stem cell suspension or chondroitinase ABC 1 mm from the edge of spinal cord damage zone. Chondroitinase ABC was first injected, and bone marrow mesenchymal stem cell suspension was injected on the next day in the combination group. At 14 days, the mean Basso, Beattie and Bresnahan score of the rats in the combination group was higher than other groups. Hematoxylin-eosin staining showed that the necrotic area was significantly reduced in the combination group compared with other groups. Glial fibrillary acidic protein-chondroitin sulfate proteoglycan double staining showed that the damage zone of astrocytic scars was significantly reduced without the cavity in the combination group. Glial fibrillary acidic protein/growth associated protein-43 double immunostaining revealed that positive fibers traversed the damage zone in the combination group. These results suggest that the combination of chondroitinase ABC and bone marrow mesenchymal stem cell transplantation contributes to the repair of spinal cord injury. PMID:25206389

Some applications of nanotechnologies in stem cells research

International Nuclear Information System (INIS)

Belicchi, M.; Cancedda, R.; Cedola, A.; Fiori, F.; Gavina, M.; Giuliani, A.; Komlev, V.S.; Lagomarsino, S.; Mastrogiacomo, M.; Renghini, C.; Rustichelli, F.

2009-01-01

Stem cell based tissue engineering therapies involve the administration of ex vivo manipulated stem cell populations with the purpose of repairing and regenerating damaged or diseased tissue. Currently available methods of monitoring transplanted cells are quite limited. To monitor the outcomes of stem cell therapy longitudinally requires the development of non-destructive strategies that are capable of identifying the location, magnitude, and duration of cellular survival and fate. The recent development of imaging techniques offers great potential to address these critical issues by non-invasively tracking the fate of the transplanted cells. This review offers a focused presentation of some examples of the use of imaging techniques connected to the nanotechnological world in research areas related to stem cells. In particular investigations will be considered concerning tissue-engineered bone, treatment of intervertebral disc degeneration, treatment by human stem cells of muscular dystrophy of Duchenne in small animal models and the repair of spinal cord injuries.

Some applications of nanotechnologies in stem cells research

Energy Technology Data Exchange (ETDEWEB)

Belicchi, M. [Fondazione IRCCS Ospedale Policlinico di Milano, Via Francesco Sforza, Milano 20122 (Italy); Cancedda, R. [Istituto Nazionale per la Ricerca sul Cancro and Dipartimento di Oncologia Biologia e Genetica - Universita di Genova, Largo R. Benzi 10, Genova 16132 (Italy); Cedola, A. [Istituto di Fotonica e Nanotecnologie - CNR, Via Cinto Romano 42, Roma 00156 (Italy); Fiori, F. [Dipartimento S.A.I.F.E.T. Sezione di Scienze Fisiche - Universita' Politecnica delle Marche, Via Brecce Bianche, Ancona 60131 (Italy); INBB - Istituto Nazionale Biostrutture e Biosistemi (Italy); CNISM - Matec (Ancona) (Italy); Gavina, M. [Fondazione IRCCS Ospedale Policlinico di Milano, Via Francesco Sforza, Milano 20122 (Italy); Giuliani, A. [Dipartimento S.A.I.F.E.T. Sezione di Scienze Fisiche - Universita' Politecnica delle Marche, Via Brecce Bianche, Ancona 60131 (Italy); CNISM - Matec (Ancona) (Italy); Komlev, V.S. [Dipartimento S.A.I.F.E.T. Sezione di Scienze Fisiche - Universita' Politecnica delle Marche, Via Brecce Bianche, Ancona 60131 (Italy); Institute for Physical Chemistry of Ceramics, Russian Academy of Sciences, Ozernaya 48, 119361 Moscow (Russian Federation); Lagomarsino, S. [Istituto di Fotonica e Nanotecnologie - CNR, Via Cinto Romano 42, Roma 00156 (Italy); Mastrogiacomo, M. [Istituto Nazionale per la Ricerca sul Cancro and Dipartimento di Oncologia Biologia e Genetica - Universita di Genova, Largo R. Benzi 10, Genova 16132 (Italy); Renghini, C. [Dipartimento S.A.I.F.E.T. Sezione di Scienze Fisiche - Universita' Politecnica delle Marche, Via Brecce Bianche, Ancona 60131 (Italy); INBB - Istituto Nazionale Biostrutture e Biosistemi (Italy); CNISM - Matec (Ancona) (Italy); Rustichelli, F., E-mail: f.rustichelli@univpm.i [Dipartimento S.A.I.F.E.T. Sezione di Scienze Fisiche - Universita' Politecnica delle Marche, Via Brecce Bianche, Ancona 60131 (Italy); INBB - Istituto Nazionale Biostrutture e Biosistemi (Italy); CNISM - Matec (Ancona) (Italy)

2009-12-15

Stem cell based tissue engineering therapies involve the administration of ex vivo manipulated stem cell populations with the purpose of repairing and regenerating damaged or diseased tissue. Currently available methods of monitoring transplanted cells are quite limited. To monitor the outcomes of stem cell therapy longitudinally requires the development of non-destructive strategies that are capable of identifying the location, magnitude, and duration of cellular survival and fate. The recent development of imaging techniques offers great potential to address these critical issues by non-invasively tracking the fate of the transplanted cells. This review offers a focused presentation of some examples of the use of imaging techniques connected to the nanotechnological world in research areas related to stem cells. In particular investigations will be considered concerning tissue-engineered bone, treatment of intervertebral disc degeneration, treatment by human stem cells of muscular dystrophy of Duchenne in small animal models and the repair of spinal cord injuries.

Deterministic Encapsulation of Human Cardiac Stem Cells in Variable Composition Nanoporous Gel Cocoons To Enhance Therapeutic Repair of Injured Myocardium.

Science.gov (United States)

Kanda, Pushpinder; Alarcon, Emilio I; Yeuchyk, Tanya; Parent, Sandrine; de Kemp, Robert A; Variola, Fabio; Courtman, David; Stewart, Duncan J; Davis, Darryl R

2018-04-20

Although cocooning explant-derived cardiac stem cells (EDCs) in protective nanoporous gels (NPGs) prior to intramyocardial injection boosts long-term cell retention, the number of EDCs that finally engraft is trivial and unlikely to account for salutary effects on myocardial function and scar size. As such, we investigated the effect of varying the NPG content within capsules to alter the physical properties of cocoons without influencing cocoon dimensions. Increasing NPG concentration enhanced cell migration and viability while improving cell-mediated repair of injured myocardium. Given that the latter occurred with NPG content having no detectable effect on the long-term engraftment of transplanted cells, we found that changing the physical properties of cocoons prompted explant-derived cardiac stem cells to produce greater amounts of cytokines, nanovesicles, and microRNAs that boosted the generation of new blood vessels and new cardiomyocytes. Thus, by altering the physical properties of cocoons by varying NPG content, the paracrine signature of encapsulated cells can be enhanced to promote greater endogenous repair of injured myocardium.

The Potential of Stem Cells in Treatment of Traumatic Brain Injury.

Science.gov (United States)

Weston, Nicole M; Sun, Dong

2018-01-25

Traumatic brain injury (TBI) is a global public health concern, with limited treatment options available. Despite improving survival rate after TBI, treatment is lacking for brain functional recovery and structural repair in clinic. Recent studies have suggested that the mature brain harbors neural stem cells which have regenerative capacity following brain insults. Much progress has been made in preclinical TBI model studies in understanding the behaviors, functions, and regulatory mechanisms of neural stem cells in the injured brain. Different strategies targeting these cell population have been assessed in TBI models. In parallel, cell transplantation strategy using a wide range of stem cells has been explored for TBI treatment in pre-clinical studies and some in clinical trials. This review summarized strategies which have been explored to enhance endogenous neural stem cell-mediated regeneration and recent development in cell transplantation studies for post-TBI brain repair. Thus far, neural regeneration through neural stem cells either by modulating endogenous neural stem cells or by stem cell transplantation has attracted much attention. It is highly speculated that targeting neural stem cells could be a potential strategy to repair and regenerate the injured brain. Neuroprotection and neuroregeneration are major aspects for TBI therapeutic development. With technique advancement, it is hoped that stem cell-based therapy targeting neuroregeneration will be able to translate to clinic in not so far future.

A functional model for adult stem cells in epithelial tissues.

NARCIS (Netherlands)

Verstappen, J.; Katsaros, C.; Torensma, R.; Hoff, J.W. Von den

2009-01-01

Tissue turnover, regeneration, and repair take place throughout life. Stem cells are key players in these processes. The characteristics and niches of the stem cell populations in different tissues, and even in related tissues, vary extensively. In this review, stem cell differentiation and stem

Lung Basal Stem Cells Rapidly Repair DNA Damage Using the Error-Prone Nonhomologous End-Joining Pathway

Science.gov (United States)

Weeden, Clare E.; Chen, Yunshun; Ma, Stephen B.; Hu, Yifang; Ramm, Georg; Sutherland, Kate D.; Smyth, Gordon K.

2017-01-01

Lung squamous cell carcinoma (SqCC), the second most common subtype of lung cancer, is strongly associated with tobacco smoking and exhibits genomic instability. The cellular origins and molecular processes that contribute to SqCC formation are largely unexplored. Here we show that human basal stem cells (BSCs) isolated from heavy smokers proliferate extensively, whereas their alveolar progenitor cell counterparts have limited colony-forming capacity. We demonstrate that this difference arises in part because of the ability of BSCs to repair their DNA more efficiently than alveolar cells following ionizing radiation or chemical-induced DNA damage. Analysis of mice harbouring a mutation in the DNA-dependent protein kinase catalytic subunit (DNA-PKcs), a key enzyme in DNA damage repair by nonhomologous end joining (NHEJ), indicated that BSCs preferentially repair their DNA by this error-prone process. Interestingly, polyploidy, a phenomenon associated with genetically unstable cells, was only observed in the human BSC subset. Expression signature analysis indicated that BSCs are the likely cells of origin of human SqCC and that high levels of NHEJ genes in SqCC are correlated with increasing genomic instability. Hence, our results favour a model in which heavy smoking promotes proliferation of BSCs, and their predilection for error-prone NHEJ could lead to the high mutagenic burden that culminates in SqCC. Targeting DNA repair processes may therefore have a role in the prevention and therapy of SqCC. PMID:28125611

Stem Cells in Regenerative Medicine

OpenAIRE

Sykova, Eva; Forostyak, Serhiy

2013-01-01

Background: A number of cardiovascular, neurological, musculoskeletal and other diseases have a limited capacity for repair and only a modest progress has been made in treatment of brain diseases. The discovery of stem cells has opened new possibilities for the treatment of these maladies, and cell therapy now stands at the cutting-edge of modern regenerative medicine and tissue engineering. Experimental data and the first clinical trials employing stem cells have shown their broad therapeuti...

Myocardium repair with stem cell therapy

International Nuclear Information System (INIS)

Peix, Amalia; Hidalgo, Jose; Dorticos, Elvira; Llerena, Lorenzo; Paredes, Angel; Torres, Maritza; Macias, Consuelo; Del Valle, Lazaro; Cabrera, Lazaro O; Carrillo, Regla; Mena, Eric; Fernandez, Yoel

2006-01-01

With the aim of assessing the efficacy of bone marrow-derived stem cells transplantation in patients with myocardial infarction and severe chronic heart failure through nuclear cardiology techniques, 15 revascularized patients were studied: nine (Group I) received autologous bone marrow-derived stem cells. The other six were controls (Group II). All underwent a clinical evaluation, radionuclide ventriculography, and gated-SPECT myocardial perfusion scintigraphy (MIBI-technetium99m, two-day protocol: dipyridamole - rest), before and three months after the procedure. At three months there was a clinical improvement in 89% of patients from Group I. The left ventricular ejection fraction increased: from 32±9% to 44±13% (p=0.03; Group I) and from 38±2% to 48±14% (p NS; Group II). The peak filling rate improved from 120±11 to 196±45 EDV/sec (p=0.03; Group I). The dipyridamole summed score diminished significantly only in Group I (from 35±5 to 23±14; p=0.02). The perfusion improvement was related to the implantation site in 60% of cases. We conclude that the bone marrow-derived stem cells transplantation is effective in patients with severe chronic heart failure of ischemic origin (au)

Stem cells and respiratory diseases

Energy Technology Data Exchange (ETDEWEB)

Abreu, Soraia Carvalho; Maron-Gutierrez, Tatiana; Garcia, Cristiane Sousa Nascimento Baez; Morales, Marcelo Marcos; Rocco, Patricia Rieken Macedo [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Biofisica Carlos Chagas Filho. Lab. de Investigacao]. E-mail: prmrocco@biof.ufrj.br

2008-12-15

Stem cells have a multitude of clinical implications in the lung. This article is a critical review that includes clinical and experimental studies of MedLine and SciElo database in the last 10 years, where we highlight the effects of stem cell therapy in acute respiratory distress syndrome or more chronic disorders such as lung fibrosis and emphysema. Although, many studies have shown the beneficial effects of stem cells in lung development, repair and remodeling; some important questions need to be answered to better understand the mechanisms that control cell division and differentiation, therefore enabling the use of cell therapy in human respiratory diseases. (author)

Stem cells and respiratory diseases

International Nuclear Information System (INIS)

Abreu, Soraia Carvalho; Maron-Gutierrez, Tatiana; Garcia, Cristiane Sousa Nascimento Baez; Morales, Marcelo Marcos; Rocco, Patricia Rieken Macedo

2008-01-01

Stem cells have a multitude of clinical implications in the lung. This article is a critical review that includes clinical and experimental studies of MedLine and SciElo database in the last 10 years, where we highlight the effects of stem cell therapy in acute respiratory distress syndrome or more chronic disorders such as lung fibrosis and emphysema. Although, many studies have shown the beneficial effects of stem cells in lung development, repair and remodeling; some important questions need to be answered to better understand the mechanisms that control cell division and differentiation, therefore enabling the use of cell therapy in human respiratory diseases. (author)

Heterogeneous Stem Cells in Skin Homeostatis and Wound Repair

Directory of Open Access Journals (Sweden)

Anna Meilana

2015-08-01

Full Text Available BACKGROUND: The skin protects mammals from insults, infection and dehydration and enables thermoregulation and sensory perception. Various skin-resident cells carry out these diverse functions. Constant turnover of cells and healing upon injury necessitate multiple reservoirs of stem cells. The skin is a complex organ harboring several distinct populations of stem cells and a rich array of cell types. Advances in genetic and imaging tools have brought new findings about the lineage relationships between skin stem cells and their progeny. Such knowledge may offer novel avenues for therapeutics and regenerative medicine. CONTENT: In the past years, our view of the mechanisms that govern skin homeostasis and regeneration have markedly changed. New populations of stem cells have been identified that behave spatio-temporally differently in healthy tissues and in situations of damage, indicating that a great level of stem cell heterogeneity is present in the skin. There are believed to be distinct populations of stem cells in different locations. The lineages that they feed are normally constrained by signals from their local environment, but they can give rise to all epidermal lineages in response to appropriate stimuli. Given the richness of structures such as blood vessels, subcutaneous fat, innervation and the accumulation of fibroblasts under the upper parts of the rete ridges (in the case of human skin, it is reasonable to speculate that the microenvironment might be essential for interfollicular epidermal homeostasis. The bloodstream is probably the main source of long-range signals reaching the skin, and cues provided by the vascular niche might be essential for skin homeostasis. SUMMARY: A key function of the interfollicular epidermis is to act as a protective interface between the body and the external environment, and it contains several architectural elements that enable it to fulfill this function. All elements of the epidermis play

Mesenchymal stem cells induce dermal fibroblast responses to injury

International Nuclear Information System (INIS)

Smith, Andria N.; Willis, Elise; Chan, Vincent T.; Muffley, Lara A.; Isik, F. Frank; Gibran, Nicole S.; Hocking, Anne M.

2010-01-01

Although bone marrow-derived mesenchymal stem cells have been shown to promote repair when applied to cutaneous wounds, the mechanism for this response remains to be determined. The aim of this study was to determine the effects of paracrine signaling from mesenchymal stem cells on dermal fibroblast responses to injury including proliferation, migration and expression of genes important in wound repair. Dermal fibroblasts were co-cultured with bone marrow-derived mesenchymal stem cells grown in inserts, which allowed for paracrine interactions without direct cell contact. In this co-culture model, bone marrow-derived mesenchymal stem cells regulate dermal fibroblast proliferation, migration and gene expression. When co-cultured with mesenchymal stem cells, dermal fibroblasts show increased proliferation and accelerated migration in a scratch assay. A chemotaxis assay also demonstrated that dermal fibroblasts migrate towards bone marrow-derived mesenchymal stem cells. A PCR array was used to analyze the effect of mesenchymal stem cells on dermal fibroblast gene expression. In response to mesenchymal stem cells, dermal fibroblasts up-regulate integrin alpha 7 expression and down-regulate expression of ICAM1, VCAM1 and MMP11. These observations suggest that mesenchymal stem cells may provide an important early signal for dermal fibroblast responses to cutaneous injury.

Aging differentially affects male and female neural stem cell neurogenic properties

Directory of Open Access Journals (Sweden)

Jay Waldron

2010-09-01

Full Text Available Jay Waldron1, Althea McCourty1, Laurent Lecanu1,21The Research Institute of the McGill University Health Centre, Montreal, Canada; 2Department of Medicine, McGill University, Montreal, Quebec, CanadaPurpose: Neural stem cell transplantation as a brain repair strategy is a very promising technology. However, despite many attempts, the clinical success remains very deceiving. Despite clear evidence that sexual dimorphism rules many aspects of human biology, the occurrence of a sex difference in neural stem cell biology is largely understudied. Herein, we propose to determine whether gender is a dimension that drives the fate of neural stem cells through aging. Should it occur, we believe that neural stem cell sexual dimorphism and its variation during aging should be taken into account to refine clinical approaches of brain repair strategies.Methods: Neural stem cells were isolated from the subventricular zone of three- and 20-month-old male and female Long-Evans rats. Expression of the estrogen receptors, ERα and ERβ, progesterone receptor, androgen receptor, and glucocorticoid receptor was analyzed and quantified by Western blotting on undifferentiated neural stem cells. A second set of neural stem cells was treated with retinoic acid to trigger differentiation, and the expression of neuronal, astroglial, and oligodendroglial markers was determined using Western blotting.Conclusion: We provided in vitro evidence that the fate of neural stem cells is affected by sex and aging. Indeed, young male neural stem cells mainly expressed markers of neuronal and oligodendroglial fate, whereas young female neural stem cells underwent differentiation towards an astroglial phenotype. Aging resulted in a lessened capacity to express neuron and astrocyte markers. Undifferentiated neural stem cells displayed sexual dimorphism in the expression of steroid receptors, in particular ERα and ERβ, and the expression level of several steroid receptors increased

Stem cell self-renewal in intestinal crypt

NARCIS (Netherlands)

Simons, B.D.; Clevers, H.

2011-01-01

As a rapidly cycling tissue capable of fast repair and regeneration, the intestinal epithelium has emerged as a favored model system to explore the principles of adult stem cell biology. However, until recently, the identity and characteristics of the stem cell population in both the small intestine

Hardwiring stem cell communication through tissue structure

Science.gov (United States)

Xin, Tianchi; Greco, Valentina; Myung, Peggy

2016-01-01

Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues. PMID:26967287

Treatment of radiation syndrome with emphasis on stem cell implantation

International Nuclear Information System (INIS)

Ashry, O.M.

2010-01-01

Within few years, the possibility that the human body contains cells that can repair and regenerate damaged and diseased tissue has gone from an unlikely proposition to a virtual certainty. Patients who have received doses of radiation in the potentially low to mid-lethal range (2-6 Gy) will have depression in bone-marrow function with cessation of blood-cell production leading to pancytopenia. Selection of cases for stem cell transplantation is based upon clinical signs and symptoms. Hematopoietic stem cell which produces blood cell progeny provides support for hematopoietic and other cells within the marrow, and has also been a focus for possible tissue repair. Another cell type termed mesenchymal or stromal also exists in the marrow. This cell provides support for hematopoietic and other cells within the marrow, and has also been a focus for possible tissue repair. Stem cells are obtained from bone marrow, peripheral blood, placental and umbilical cord blood, embryonic stem cells and embryonic germ cells. These cells have great potential for clinical research due to their potential to regenerate tissue. As well known, the cryo preservation process can store any cell type, particularly blood cells, for an indeterminate time. (author)

The use of mesenchymal stem cells for cartilage repair and regeneration: a systematic review.

Science.gov (United States)

Goldberg, Andy; Mitchell, Katrina; Soans, Julian; Kim, Louise; Zaidi, Razi

2017-03-09

The management of articular cartilage defects presents many clinical challenges due to its avascular, aneural and alymphatic nature. Bone marrow stimulation techniques, such as microfracture, are the most frequently used method in clinical practice however the resulting mixed fibrocartilage tissue which is inferior to native hyaline cartilage. Other methods have shown promise but are far from perfect. There is an unmet need and growing interest in regenerative medicine and tissue engineering to improve the outcome for patients requiring cartilage repair. Many published reviews on cartilage repair only list human clinical trials, underestimating the wealth of basic sciences and animal studies that are precursors to future research. We therefore set out to perform a systematic review of the literature to assess the translation of stem cell therapy to explore what research had been carried out at each of the stages of translation from bench-top (in vitro), animal (pre-clinical) and human studies (clinical) and assemble an evidence-based cascade for the responsible introduction of stem cell therapy for cartilage defects. This review was conducted in accordance to PRISMA guidelines using CINHAL, MEDLINE, EMBASE, Scopus and Web of Knowledge databases from 1st January 1900 to 30th June 2015. In total, there were 2880 studies identified of which 252 studies were included for analysis (100 articles for in vitro studies, 111 studies for animal studies; and 31 studies for human studies). There was a huge variance in cell source in pre-clinical studies both of terms of animal used, location of harvest (fat, marrow, blood or synovium) and allogeneicity. The use of scaffolds, growth factors, number of cell passages and number of cells used was hugely heterogeneous. This review offers a comprehensive assessment of the evidence behind the translation of basic science to the clinical practice of cartilage repair. It has revealed a lack of connectivity between the in vitro, pre

Adult Bone Marrow Mesenchymal Stem Cells Primed for fhe Repair of Damaged Cardiac Tissue After Myocardial Infarction

Science.gov (United States)

Marks, Edward D.

The burden of cardiovascular disease around the world is growing, despite improvements in hospital care and time to treatment. As more people survive an initial myocardial infarction (MI), the decompensated heart tissue is strained, leading to heart failure (HF) and an increased risk for a second MI. While extensive progress has been made in treating the symptoms after MI, including HF and angina, little success has come from repairing the damaged heart tissue to alleviate the progression to these end- stage symptoms. One promising area of regenerative research has been the use of adult stem cells, particularly from the bone marrow (BMSCs). These cells can differentiate towards the cardiac cell lineage in vitro while producing trophic factors that can repair damaged tissue. When placed in the heart after MI though, BMSCs have mixed results, producing profound changes in some patients but zero or even negative effects in others. In this report, we used BMSCs as a stem cell base for a regenerative medicine system for the repair of damaged cardiac tissue. These cells are seeded on a polycaprolactone nanoscaffolding support system, which provides a growth substrate for in vitro work, as well as a housing system for protected in vivo delivery. When the nanoscaffold is pre-coated with a novel combination of a cardiac protein, thymosin beta4 (Tbeta4), and a small molecule effector of the WNT protein pathway, IWP-2, BMSCs differentiated towards the cardiac lineage in as little as 24hours. When injected into rat hearts that have been given an ischemic MI, the nanoscaffolding system slowly dissolves, leaving the cells in place of the damaged cardiac tissue. After two weeks of monitoring, BMSCs are present within the damaged hearts, as evidenced by immunofluorescence and nanoparticle tracking. Injections of the nanoscaffolding/cell system led to robust healing of the rat hearts that had been given small- and medium- damage heart attacks, outperforming PBS sham and cell

Stem Cell Antigen-1 in Skeletal Muscle Function

OpenAIRE

Bernstein, Harold S.; Samad, Tahmina; Cholsiripunlert, Sompob; Khalifian, Saami; Gong, Wenhui; Ritner, Carissa; Aurigui, Julian; Ling, Vivian; Wilschut, Karlijn J.; Bennett, Stephen; Hoffman, Julien; Oishi, Peter

2013-01-01

Stem cell antigen-1 (Sca-1) is a member of the Ly-6 multigene family encoding highly homologous, glycosyl-phosphatidylinositol-anchored membrane proteins. Sca-1 is expressed on muscle-derived stem cells and myogenic precursors recruited to sites of muscle injury. We previously reported that inhibition of Sca-1 expression stimulated myoblast proliferation in vitro and regulated the tempo of muscle repair in vivo. Despite its function in myoblast expansion during muscle repair, a role for Sca-1...

EGR1 induces tenogenic differentiation of tendon stem cells and promotes rabbit rotator cuff repair.

Science.gov (United States)

Tao, Xu; Liu, Junpeng; Chen, Lei; Zhou, You; Tang, Kanglai

2015-01-01

The rate of healing failure after surgical repair of chronic rotator cuff tears is considerably high. The aim of this study was to investigate the function of the zinc finger transcription factor early growth response 1 (EGR1) in the differentiation of tendon stem cells (TSCs) and in tendon formation, healing, and tendon tear repair using an animal model of rotator cuff repair. Tenocyte, adipocyte, osteocyte, and chondrocyte differentiation as well as the expression of related genes were determined in EGR1-overexpressing TSCs (EGR1-TSCs) using tissue-specific staining, immunofluorescence staining, quantitative PCR, and western blotting. A rabbit rotator cuff repair model was established, and TSCs and EGR1-TSCs in a fibrin glue carrier were applied onto repair sites. The rabbits were sacrificed 8 weeks after repair operation, and tissues were histologically evaluated and tenocyte-related gene expression was determined. EGR1 induced tenogenic differentiation of TSCs and inhibited non-tenocyte differentiation of TSCs. Furthermore, EGR1 promoted tendon repair in a rabbit model of rotator cuff injury. The BMP12/Smad1/5/8 signaling pathway was involved in EGR1-induced tenogenic differentiation and rotator cuff tendon repair. EGR1 plays a key role in tendon formation, healing, and repair through BMP12/Smad1/5/8 pathway. EGR1-TSCs is a promising treatment for rotator cuff tendon repair surgeries. © 2015 S. Karger AG, Basel.

EGR1 Induces Tenogenic Differentiation of Tendon Stem Cells and Promotes Rabbit Rotator Cuff Repair

Directory of Open Access Journals (Sweden)

Xu Tao

2015-01-01

Full Text Available Background/Aims: The rate of healing failure after surgical repair of chronic rotator cuff tears is considerably high. The aim of this study was to investigate the function of the zinc finger transcription factor early growth response 1 (EGR1 in the differentiation of tendon stem cells (TSCs and in tendon formation, healing, and tendon tear repair using an animal model of rotator cuff repair. Methods: Tenocyte, adipocyte, osteocyte, and chondrocyte differentiation as well as the expression of related genes were determined in EGR1-overexpressing TSCs (EGR1-TSCs using tissue-specific staining, immunofluorescence staining, quantitative PCR, and western blotting. A rabbit rotator cuff repair model was established, and TSCs and EGR1-TSCs in a fibrin glue carrier were applied onto repair sites. The rabbits were sacrificed 8 weeks after repair operation, and tissues were histologically evaluated and tenocyte-related gene expression was determined. Results: EGR1 induced tenogenic differentiation of TSCs and inhibited non-tenocyte differentiation of TSCs. Furthermore, EGR1 promoted tendon repair in a rabbit model of rotator cuff injury. The BMP12/Smad1/5/8 signaling pathway was involved in EGR1-induced tenogenic differentiation and rotator cuff tendon repair. Conclusion: EGR1 plays a key role in tendon formation, healing, and repair through BMP12/Smad1/5/8 pathway. EGR1-TSCs is a promising treatment for rotator cuff tendon repair surgeries.

Dynamic dependence on ATR and ATM for double-strand break repair in human embryonic stem cells and neural descendants.

Science.gov (United States)

Adams, Bret R; Golding, Sarah E; Rao, Raj R; Valerie, Kristoffer

2010-04-02

The DNA double-strand break (DSB) is the most toxic form of DNA damage. Studies aimed at characterizing DNA repair during development suggest that homologous recombination repair (HRR) is more critical in pluripotent cells compared to differentiated somatic cells in which nonhomologous end joining (NHEJ) is dominant. We have characterized the DNA damage response (DDR) and quality of DNA double-strand break (DSB) repair in human embryonic stem cells (hESCs), and in vitro-derived neural cells. Resolution of ionizing radiation-induced foci (IRIF) was used as a surrogate for DSB repair. The resolution of gamma-H2AX foci occurred at a slower rate in hESCs compared to neural progenitors (NPs) and astrocytes perhaps reflective of more complex DSB repair in hESCs. In addition, the resolution of RAD51 foci, indicative of active homologous recombination repair (HRR), showed that hESCs as well as NPs have high capacity for HRR, whereas astrocytes do not. Importantly, the ATM kinase was shown to be critical for foci formation in astrocytes, but not in hESCs, suggesting that the DDR is different in these cells. Blocking the ATM kinase in astrocytes not only prevented the formation but also completely disassembled preformed repair foci. The ability of hESCs to form IRIF was abrogated with caffeine and siRNAs targeted against ATR, implicating that hESCs rely on ATR, rather than ATM for regulating DSB repair. This relationship dynamically changed as cells differentiated. Interestingly, while the inhibition of the DNA-PKcs kinase (and presumably non-homologous endjoining [NHEJ]) in astrocytes slowed IRIF resolution it did not in hESCs, suggesting that repair in hESCs does not utilize DNA-PKcs. Altogether, our results show that hESCs have efficient DSB repair that is largely ATR-dependent HRR, whereas astrocytes critically depend on ATM for NHEJ, which, in part, is DNA-PKcs-independent.

Cartilage Repair With Autologous Bone Marrow Mesenchymal Stem Cell Transplantation: Review of Preclinical and Clinical Studies.

Science.gov (United States)

Yamasaki, Shinya; Mera, Hisashi; Itokazu, Maki; Hashimoto, Yusuke; Wakitani, Shigeyuki

2014-10-01

Clinical trials of various procedures, including bone marrow stimulation, mosaicplasty, and autologous chondrocyte implantation, have been explored to treat articular cartilage defects. However, all of them have some demerits. We focused on autologous culture-expanded bone marrow mesenchymal stem cells (BMSC), which can proliferate without losing their capacity for differentiation. First, we transplanted BMSC into the defective articular cartilage of rabbit and succeeded in regenerating osteochondral tissue. We then applied this transplantation in humans. Our previous reports showed that treatment with BMSC relieves the clinical symptoms of chondral defects in the knee and elbow joint. We investigated the efficacy of BMSC for osteoarthritic knee treated with high tibial osteotomy, by comparing 12 BMSC-transplanted patients with 12 cell-free patients. At 16-month follow-up, although the difference in clinical improvement between both groups was not significant, the arthroscopic and histological grading score was better in the cell-transplanted group. At the over 10-year follow-up, Hospital for Special Surgery knee scores improved to 76 and 73 in the BMSC-transplanted and cell-free groups, respectively, which were better than preoperative scores. Additionally, neither tumors nor infections were observed in all patients, and in the clinical study, we have never observed hypertrophy of repaired tissue, thereby guaranteeing the clinical safety of this therapy. Although we have never observed calcification above the tidemark in rabbit model and human histologically, the repair cartilage was not completely hyaline cartilage. To elucidate the optimum conditions for cell therapy, other stem cells, culture conditions, growth factors, and gene transfection methods should be explored.

Guiding osteogenesis of mesenchymal stem cells using carbon-based nanomaterials

Science.gov (United States)

Kang, Ee-Seul; Kim, Da-Seul; Suhito, Intan Rosalina; Choo, Sung-Sik; Kim, Seung-Jae; Song, Inbeom; Kim, Tae-Hyung

2017-01-01

In the field of regenerative medicine, stem cells are highly promising due to their innate ability to generate multiple types of cells that could replace/repair damaged parts of human organs and tissues. It has been reported that both in vitro and in vivo function/survival of stem cells could significantly be improved by utilizing functional materials such as biodegradable polymers, metal composites, nanopatterns and nanohybrid particles. Of various biocompatible materials available for use in stem cell-based therapy and research, carbon-based materials—including fullerenes graphene/graphene oxide and carbon nanotubes—have been found to possess unique physicochemical characteristics that contribute to the effective guidance of stem cell differentiation into specific lineages. In this review, we discuss a number of previous reports that investigated the use of carbon-based materials to control stem cell behavior, with a particular focus on their immense potential to guide the osteogenesis of mesenchymal stem cells (MSCs). We hope that this review will provide information on the full potential of using various carbon-based materials in stem cell-mediated regenerative therapy, particularly for bone regeneration and repair.

Recent advances in hematopoietic stem cell biology

DEFF Research Database (Denmark)

Bonde, Jesper; Hess, David A; Nolta, Jan A

2004-01-01

PURPOSE OF REVIEW: Exciting advances have been made in the field of hematopoietic stem cell biology during the past year. This review summarizes recent progress in the identification, culture, and in vivo tracking of hematopoietic stem cells. RECENT FINDINGS: The roles of Wnt and Notch proteins...... in regulating stem cell renewal in the microenvironment, and how these molecules can be exploited in ex vivo stem cell culture, are reviewed. The importance of identification of stem cells using functional as well as phenotypic markers is discussed. The novel field of nanotechnology is then discussed...... in the context of stem cell tracking in vivo. This review concludes with a section on the unexpected potential of bone marrow-derived stem cells to contribute to the repair of damaged tissues. The contribution of cell fusion to explain the latter phenomenon is discussed. SUMMARY: Because of exciting discoveries...

Exonuclease 1 is a critical mediator of survival during DNA double strand break repair in nonquiescent hematopoietic stem and progenitor cells.

Science.gov (United States)

Desai, Amar; Qing, Yulan; Gerson, Stanton L

2014-02-01

Hematopoietic stem cell (HSC) populations require DNA repair pathways to maintain their long-term survival and reconstitution capabilities, but mediators of these processes are still being elucidated. Exonuclease 1 (Exo1) participates in homologous recombination (HR) and Exo1 loss results in impaired 5' HR end resection. We use cultured Exo1(mut) fibroblasts and bone marrow to demonstrate that loss of Exo1 function results in defective HR in cycling cells. Conversely, in Exo1(mut) mice HR is not required for maintenance of quiescent HSCs at steady state, confirming the steady state HSC reliance on nonhomologous end joining (NHEJ). Exo1(mut) mice sustained serial repopulation, displayed no defect in competitive repopulation or niche occupancy, and exhibited no increased sensitivity to whole body ionizing radiation. However, when Exo1(mut) HSCs were pushed into cell cycle in vivo with 5-fluorouracil or poly IC, the hematopoietic population became hypersensitive to IR, resulting in HSC defects and animal death. We propose Exo1-mediated HR is dispensable for stem cell function in quiescent HSC, whereas it is essential to HSC response to DNA damage processing after cell cycle entry, and its loss is not compensated by intact NHEJ. In HSCs, the maintenance of stem cell function after DNA damage is dependent on the DNA repair capacity, segregated by active versus quiescent points in cell cycle. © AlphaMed Press.

Effectiveness of mesenchymal stems cells cultured by hanging drop vs. conventional culturing on the repair of hypoxic-ischemic-damaged mouse brains, measured by stemness gene expression

OpenAIRE

Lou Yongli; Guo Dewei; Zhang Hui; Song Laijun

2016-01-01

In this study, we investigated the therapeutic effects of Human Mesenchymal Stem Cells (hMSCs) cultured by hanging drop and conventional culturing methods on cerebellar repair in hypoxic-ischemic (HI) brain injured mice. Real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to analyze the expression levels of three stemness genes, Oct4, Sox2 and Nanog, and the migration related gene CXCR4. MSC prepared by hanging drop or conventional techniques were adminis...

Biochemistry of epidermal stem cells.

Science.gov (United States)

Eckert, Richard L; Adhikary, Gautam; Balasubramanian, Sivaprakasam; Rorke, Ellen A; Vemuri, Mohan C; Boucher, Shayne E; Bickenbach, Jackie R; Kerr, Candace

2013-02-01

The epidermis is an important protective barrier that is essential for maintenance of life. Maintaining this barrier requires continuous cell proliferation and differentiation. Moreover, these processes must be balanced to produce a normal epidermis. The stem cells of the epidermis reside in specific locations in the basal epidermis, hair follicle and sebaceous glands and these cells are responsible for replenishment of this tissue. A great deal of effort has gone into identifying protein epitopes that mark stem cells, in identifying stem cell niche locations, and in understanding how stem cell populations are related. We discuss these studies as they apply to understanding normal epidermal homeostasis and skin cancer. An assortment of stem cell markers have been identified that permit assignment of stem cells to specific regions of the epidermis, and progress has been made in understanding the role of these cells in normal epidermal homeostasis and in conditions of tissue stress. A key finding is the multiple stem cell populations exist in epidermis that give rise to different structures, and that multiple stem cell types may contribute to repair in damaged epidermis. Understanding epidermal stem cell biology is likely to lead to important therapies for treating skin diseases and cancer, and will also contribute to our understanding of stem cells in other systems. This article is part of a Special Issue entitled Biochemistry of Stem Cells. Copyright © 2012 Elsevier B.V. All rights reserved.

Hardwiring Stem Cell Communication through Tissue Structure.

Science.gov (United States)

Xin, Tianchi; Greco, Valentina; Myung, Peggy

2016-03-10

Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function, but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues. Copyright © 2016 Elsevier Inc. All rights reserved.

Programmed Application of Transforming Growth Factor β3 and Rac1 Inhibitor NSC23766 Committed Hyaline Cartilage Differentiation of Adipose-Derived Stem Cells for Osteochondral Defect Repair.

Science.gov (United States)

Zhu, Shouan; Chen, Pengfei; Wu, Yan; Xiong, Si; Sun, Heng; Xia, Qingqing; Shi, Libing; Liu, Huanhuan; Ouyang, Hong Wei

2014-10-01

Hyaline cartilage differentiation is always the challenge with application of stem cells for joint repair. Transforming growth factors (TGFs) and bone morphogenetic proteins can initiate cartilage differentiation but often lead to hypertrophy and calcification, related to abnormal Rac1 activity. In this study, we developed a strategy of programmed application of TGFβ3 and Rac1 inhibitor NSC23766 to commit the hyaline cartilage differentiation of adipose-derived stem cells (ADSCs) for joint cartilage repair. ADSCs were isolated and cultured in a micromass and pellet culture model to evaluate chondrogenic and hypertrophic differentiation. The function of Rac1 was investigated with constitutively active Rac1 mutant and dominant negative Rac1 mutant. The efficacy of ADSCs with programmed application of TGFβ3 and Rac1 inhibitor for cartilage repair was studied in a rat model of osteochondral defects. The results showed that TGFβ3 promoted ADSCs chondro-lineage differentiation and that NSC23766 prevented ADSC-derived chondrocytes from hypertrophy in vitro. The combination of ADSCs, TGFβ3, and NSC23766 promoted quality osteochondral defect repair in rats with much less chondrocytes hypertrophy and significantly higher International Cartilage Repair Society macroscopic and microscopic scores. The findings have illustrated that programmed application of TGFβ3 and Rac1 inhibitor NSC23766 can commit ADSCs to chondro-lineage differentiation and improve the efficacy of ADSCs for cartilage defect repair. These findings suggest a promising stem cell-based strategy for articular cartilage repair. ©AlphaMed Press.

Schwann Cell Precursors from Human Pluripotent Stem Cells as a Potential Therapeutic Target for Myelin Repair.

Science.gov (United States)

Kim, Han-Seop; Lee, Jungwoon; Lee, Da Yong; Kim, Young-Dae; Kim, Jae Yun; Lim, Hyung Jin; Lim, Sungmin; Cho, Yee Sook

2017-06-06

Schwann cells play a crucial role in successful nerve repair and regeneration by supporting both axonal growth and myelination. However, the sources of human Schwann cells are limited both for studies of Schwann cell development and biology and for the development of treatments for Schwann cell-associated diseases. Here, we provide a rapid and scalable method to produce self-renewing Schwann cell precursors (SCPs) from human pluripotent stem cells (hPSCs), using combined sequential treatment with inhibitors of the TGF-β and GSK-3 signaling pathways, and with neuregulin-1 for 18 days under chemically defined conditions. Within 1 week, hPSC-derived SCPs could be differentiated into immature Schwann cells that were functionally confirmed by their secretion of neurotrophic factors and their myelination capacity in vitro and in vivo. We propose that hPSC-derived SCPs are a promising, unlimited source of functional Schwann cells for treating demyelination disorders and injuries to the peripheral nervous system. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

The Promise and Perils of Stem Cell Therapeutics

OpenAIRE

Daley, George Q.

2012-01-01

Stem cells are the seeds of tissue repair and regeneration and a promising source for novel therapies. However, apart from hematopoietic stem cell (HSC) transplantation for hematologic disease, essentially all other stem cell treatments remain experimental. High hopes have inspired numerous clinical trials, but it has been difficult to obtain unequivocal evidence for robust clinical benefit, likely owing to our primitive state of knowledge about therapeutic mechanisms. Outside the standard cl...

Pluripotent Stem Cells in Research and Treatment of Hemoglobinopathies

Science.gov (United States)

Arora, Natasha; Daley, George Q.

2012-01-01

Pluripotent stem cells (PSCs) hold great promise for research and treatment of hemoglobinopathies. In principle, patient-specific induced pluripotent stem cells could be derived from a blood sample, genetically corrected to repair the disease-causing mutation, differentiated into hematopoietic stem cells (HSCs), and returned to the patient to provide a cure through autologous gene and cell therapy. However, there are many challenges at each step of this complex treatment paradigm. Gene repair is currently inefficient in stem cells, but use of zinc finger nucleases and transcription activator-like effector nucleases appear to be a major advance. To date, no successful protocol exists for differentiating PSCs into definitive HSCs. PSCs can be directly differentiated into primitive red blood cells, but not yet in sufficient numbers to enable treating patients, and the cost of clinical scale differentiation is prohibitively expensive with current differentiation methods and efficiencies. Here we review the progress, promise, and remaining hurdles in realizing the potential of PSCs for cell therapy. PMID:22474618

Stem cell self-renewal in intestinal crypt

International Nuclear Information System (INIS)

Simons, Benjamin D.; Clevers, Hans

2011-01-01

As a rapidly cycling tissue capable of fast repair and regeneration, the intestinal epithelium has emerged as a favored model system to explore the principles of adult stem cell biology. However, until recently, the identity and characteristics of the stem cell population in both the small intestine and colon has remained the subject of debate. Recent studies based on targeted lineage tracing strategies, combined with the development of an organotypic culture system, have identified the crypt base columnar cell as the intestinal stem cell, and have unveiled the strategy by which the balance between proliferation and differentiation is maintained. These results show that intestinal stem cells operate in a dynamic environment in which frequent and stochastic stem cell loss is compensated by the proliferation of neighboring stem cells. We review the basis of these experimental findings and the insights they offer into the mechanisms of homeostatic stem cell regulation.

HGFA Is an Injury-Regulated Systemic Factor that Induces the Transition of Stem Cells into GAlert

Directory of Open Access Journals (Sweden)

Joseph T. Rodgers

2017-04-01

Full Text Available Summary: The activation of quiescent stem cells into the cell cycle is a key step in initiating the process of tissue repair. We recently reported that quiescent stem cells can transition into GAlert, a cellular state in which they have an increased functional ability to activate and participate in tissue repair. However, the precise molecular signals that induce GAlert in stem cells have remained elusive. Here, we show that the injury-induced regulation of hepatocyte growth factor (HGF proteolytic processing via the systemic protease, hepatocyte growth factor activator (HGFA, stimulates GAlert in skeletal muscle stem cells (MuSCs and fibro-adipogenic progenitors (FAPs. We demonstrate that administering active HGFA to animals is sufficient to induce GAlert in stem cells throughout the body and to significantly accelerate the processes of stem cell activation and tissue repair. Our data suggest that factors that induce GAlert will have broad therapeutic applications for regenerative medicine and wound healing. : Rodgers et al. show that HGFA is a systemic protease that is activated by tissue injury and relays a signal to stem cells in non-injured tissues that induces their transition into a primed, “GAlert” state in which they possess an enhanced potential to activate and repair tissue damage. Keywords: satellite cells, muscle stem cells, fibro-adipogenic progenitors, HGFA, HGF, mTORC1, cMet, stem cell quiescence, stem cell activation, GAlert

SIGNALING PATHWAYS ASSOCIATED WITH VX EXPOSURE IN MESENCHYMAL STEM CELLS

Science.gov (United States)

2017-09-01

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Director, ECBC, ATTN: RDCB-DRB-D, APG, MD 21010-5424 Excet, Inc., 8001 Braddock Road , Suite 303...Mesenchymal stem cells (MSCs) are multipotent adult stem cells that are key regulators of tissue maintenance and repair. These cells have been identified in...adipocytes) and play a significant role in tissue maintenance and repair (15, 16). MSCs have been shown to be capable of self-renewal and can be maintained

FGF2 mediates DNA repair in epidermoid carcinoma cells exposed to ionizing radiation

International Nuclear Information System (INIS)

Marie, Melanie; Hafner, Sophie; Moratille, Sandra; Vaigot, Pierre; Rigaud, Odile; Martin, Michele T.; Mine, Solene

2012-01-01

Fibroblast growth factor 2 (FGF2) is a well-known survival factor. However, its role in DNA repair is poorly documented. The present study was designed to investigate in epidermoid carcinoma cells the potential role of FGF2 in DNA repair. The side population (SP) with cancer stem cell-like properties and the main population (MP) were isolated from human A431 squamous carcinoma cells. Radiation-induced DNA damage and repair were assessed using the alkaline comet assay. FGF2 expression was quantified by enzyme linked immunosorbent assay (ELISA). SP cells exhibited rapid repair of radiation induced DNA damage and a high constitutive level of nuclear FGF2. Blocking FGF2 signaling abrogated the rapid DNA repair. In contrast, in MP cells, a slower repair of damage was associated with low basal expression of FGF2. Moreover, the addition of exogenous FGF2 accelerated DNA repair in MP cells. When irradiated, SP cells secreted FGF2, whereas MP cells did not. FGF2 was found to mediate DNA repair in epidermoid carcinoma cells. We postulate that carcinoma stem cells would be intrinsically primed to rapidly repair DNA damage by a high constitutive level of nuclear FGF2. In contrast, the main population with a low FGF2 content exhibits a lower repair rate which can be increased by exogenous FGF2. (authors)

Systemic Injection of Neural Stem/progenitor Cells in Mice With Chronic EAE

OpenAIRE

Donegà, Matteo; Giusto, Elena; Cossetti, Chiara; Schaeffer, Julia; Pluchino, Stefano

2014-01-01

Neural stem/precursor cells (NPCs) are a promising stem cell source for transplantation approaches aiming at brain repair or restoration in regenerative neurology. This directive has arisen from the extensive evidence that brain repair is achieved after focal or systemic NPC transplantation in several pre clinical models of neurological diseases.

Nonclinical safety strategies for stem cell therapies

Energy Technology Data Exchange (ETDEWEB)

Sharpe, Michaela E., E-mail: michaela_sharpe@yahoo.com [Investigative Toxicology, Drug Safety Research and Development, Pfizer Ltd, Ramsgate Road, Sandwich, CT13 9NJ (United Kingdom); Morton, Daniel [Exploratory Drug Safety, Drug Safety Research and Development, Pfizer Inc, Cambridge, 02140 (United States); Rossi, Annamaria [Investigative Toxicology, Drug Safety Research and Development, Pfizer Ltd, Ramsgate Road, Sandwich, CT13 9NJ (United Kingdom)

2012-08-01

Recent breakthroughs in stem cell biology, especially the development of the induced pluripotent stem cell techniques, have generated tremendous enthusiasm and efforts to explore the therapeutic potential of stem cells in regenerative medicine. Stem cell therapies are being considered for the treatment of degenerative diseases, inflammatory conditions, cancer and repair of damaged tissue. The safety of a stem cell therapy depends on many factors including the type of cell therapy, the differentiation status and proliferation capacity of the cells, the route of administration, the intended clinical location, long term survival of the product and/or engraftment, the need for repeated administration, the disease to be treated and the age of the population. Understanding the product profile of the intended therapy is crucial to the development of the nonclinical safety study design.

Nonclinical safety strategies for stem cell therapies

International Nuclear Information System (INIS)

Sharpe, Michaela E.; Morton, Daniel; Rossi, Annamaria

2012-01-01

Recent breakthroughs in stem cell biology, especially the development of the induced pluripotent stem cell techniques, have generated tremendous enthusiasm and efforts to explore the therapeutic potential of stem cells in regenerative medicine. Stem cell therapies are being considered for the treatment of degenerative diseases, inflammatory conditions, cancer and repair of damaged tissue. The safety of a stem cell therapy depends on many factors including the type of cell therapy, the differentiation status and proliferation capacity of the cells, the route of administration, the intended clinical location, long term survival of the product and/or engraftment, the need for repeated administration, the disease to be treated and the age of the population. Understanding the product profile of the intended therapy is crucial to the development of the nonclinical safety study design.

Spermatogonial stem cell renewal following irradiation

International Nuclear Information System (INIS)

Fabrikant, J.I.

1979-05-01

The spermatogonial cell renewal system can maintain function and a steady level of cell population for relatively long periods of continuous low-level irradiation indicating that there does not appear to be a serious accumulation, over many generations, of damage affecting proliferation. Provided the dose-rate is quite low, there is an effective selective removal of damaged cells with almost complete repair of cellular nonlethal damage. At dose-rates greater than 2 rad/day, spermatogonia are very sensitive to radiation death, and the main reason for the low tolerance to continuous stress could, in part, be the limited extent of compensatory mechanisms regulating spermatogonial cell production. However, there is some capacity to change the patterns of cellular proliferation while still remaining under homeostatic control, and this capacity appears to reside in the relatively radioresistant A/sub s/ stem-cell population. Little is known about the extent to which the spermatogonial cell population can repair nonlethal cellular radiation damage accumulated under continuous stress affecting the regenerative capacity of the tissue. After acute exposure, a minimum number of surviving type A/sub s/ stem-cells are required to repopulate the functional seminiferous epithelium, regeneration proceeds along an ordered cell stage sequence, and is dependent on the time required for all stages from type A/sub s/ spermatogonia to mature spermatozoa. Under continuous irradiation, provided the dose-rate is not too high, the repopulating ability of the seminiferous epithelium is maintained, in the presence of injury, due to initial repair and long-term repair of cellular radiation damage. There is evidence for initial repair, since a dose-rate effect exists in type A survival, at low doses. Long-term repair occurs due to differential radiosensitivities of spermatogonia

Stem Cell Therapy to Improve Burn Wound Healing

Science.gov (United States)

2017-03-01

Award Number: W81XWH-13-2-0024 TITLE: Stem Cell Therapy to Improve Burn Wound Healing PRINCIPAL INVESTIGATOR: Carl Schulman, MD, PhD, MSPH...NUMBER Stem Cell Therapy to Improve Burn Wound Healing 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Carl Schulman, MD, PhD, MSPH...treatments, steroid injections, and compression garments. Mesenchymal stem cells (MSC’s) have been used in a variety of clinical applications to repair

Stem cell research: applicability in dentistry.

Science.gov (United States)

Mathur, Shivani; Chopra, Rahul; Pandit, I K; Srivastava, Nikhil; Gugnani, Neeraj

2014-01-01

In the face of extraordinary advances in the prevention, diagnosis, and treatment of human diseases, the inability of most tissues and organs to repair and regenerate after damage is a problem that needs to be solved. Stem cell research is being pursued in the hope of achieving major medical breakthroughs. Scientists are striving to create therapies that rebuild or replace damaged cells with tissues grown from stem cells that will offer hope to people suffering from various ailments. Regeneration of damaged periodontal tissue, bone, pulp, and dentin is a problem that dentists face today. Stem cells present in dental pulp, periodontal ligament, and alveolar bone marrow have the potential to repair and regenerate teeth and periodontal structures. These stem cells can be harvested from dental pulp, periodontal ligament, and/or alveolar bone marrow; expanded; embedded in an appropriate scaffold; and transplanted back into a defect to regenerate bone and tooth structures. These cells have the potential to regenerate dentin, periodontal ligament, and cementum and can also be used to restore bone defects. The kind of scaffold, the source of cells, the type of in vitro culturing, and the type of surgical procedure to be used all require careful consideration. The endeavor is clearly multidisciplinary in nature, and the practicing dental surgeon has a critical role in it. Playing this role in the most effective way requires awareness of the huge potential associated with the use of stem cells in a clinical setting, as well as a proper understanding of the related problems.

Dynamic dependence on ATR and ATM for double-strand break repair in human embryonic stem cells and neural descendants.

Directory of Open Access Journals (Sweden)

Bret R Adams

2010-04-01

Full Text Available The DNA double-strand break (DSB is the most toxic form of DNA damage. Studies aimed at characterizing DNA repair during development suggest that homologous recombination repair (HRR is more critical in pluripotent cells compared to differentiated somatic cells in which nonhomologous end joining (NHEJ is dominant. We have characterized the DNA damage response (DDR and quality of DNA double-strand break (DSB repair in human embryonic stem cells (hESCs, and in vitro-derived neural cells. Resolution of ionizing radiation-induced foci (IRIF was used as a surrogate for DSB repair. The resolution of gamma-H2AX foci occurred at a slower rate in hESCs compared to neural progenitors (NPs and astrocytes perhaps reflective of more complex DSB repair in hESCs. In addition, the resolution of RAD51 foci, indicative of active homologous recombination repair (HRR, showed that hESCs as well as NPs have high capacity for HRR, whereas astrocytes do not. Importantly, the ATM kinase was shown to be critical for foci formation in astrocytes, but not in hESCs, suggesting that the DDR is different in these cells. Blocking the ATM kinase in astrocytes not only prevented the formation but also completely disassembled preformed repair foci. The ability of hESCs to form IRIF was abrogated with caffeine and siRNAs targeted against ATR, implicating that hESCs rely on ATR, rather than ATM for regulating DSB repair. This relationship dynamically changed as cells differentiated. Interestingly, while the inhibition of the DNA-PKcs kinase (and presumably non-homologous endjoining [NHEJ] in astrocytes slowed IRIF resolution it did not in hESCs, suggesting that repair in hESCs does not utilize DNA-PKcs. Altogether, our results show that hESCs have efficient DSB repair that is largely ATR-dependent HRR, whereas astrocytes critically depend on ATM for NHEJ, which, in part, is DNA-PKcs-independent.

Stem cells: progressions and applications in clinical medicine

Directory of Open Access Journals (Sweden)

Ali Hosseini Bereshneh

2016-05-01

Full Text Available Stem cells are undifferentiated and multi pluripotent cells which can differentiate into a variety of mature cells and tissues such as nervous tissue, muscle tissue, epithelial tissue, skeletal tissue and etc. Stem cells from all different source have three unique features: 1 Proliferative capability: Stem cells are capable of self dividing and self renewing for long periods or more than six months at least that called immortalization. 2 Undifferentiated nature: It’s considered as one of the essential characteristics of stem cell, so it doesn't have any tissue-specific construction. 3 Differentiation to the different cells from all organs: This ability can Induced by tissue specific transcription factors. Because of that, they are so important in prevention and treatment of human disease. Depending on the sources from which they derive, they have different types which can be used to produce special cells and tissues. The most significant types of stem cells are; embryonic stem cells (ESCs which are derived from embryos, adult stem cells (ASCs which are derived from differentiated cells in a specific tissue, induced pluripotent stem cells (iPSs which are produced from adult differentiated cells that have been genetically reprogrammed to act resemble to an embryonic stem cell and cord blood stem cells which contains haematopoietic stem cells and derived from the umbilical cord after gestation. By providing a medium containing of special growth factor, it is possible to orientated stem cell differentiation pathway and gained certain cells from them. The important uses of stem cells includes damaged heart tissue cells improvements and bone tissue repairing, cancer treatment, damaged neurological and spinal tissue repairing, improving burns and injuries and the treatment of diabetes, infertility and spermatogenesis dysfunction. Furthermore, the application of them in gene therapy is an important issue in the modern medicine science due to the role

Gefitinib Radiosensitizes Stem-Like Glioma Cells: Inhibition of Epidermal Growth Factor Receptor-Akt-DNA-PK Signaling, Accompanied by Inhibition of DNA Double-Strand Break Repair

International Nuclear Information System (INIS)

Kang, Khong Bee; Zhu Congju; Wong Yinling; Gao Qiuhan; Ty, Albert; Wong, Meng Cheong

2012-01-01

Purpose: We compared radiosensitivity of brain tumor stem cells (BTSCs) with matched nonstem glioma cells, and determined whether gefitinib enhanced BTSC radiosensitivity by inhibiting epidermal growth factor receptor (EGFR)–Akt-DNA–dependent protein kinase (DNA-PK) signaling, followed by enhanced DNA double-stand breaks (DSBs) and inhibition of DSB repair. Methods and Materials: Radiosensitivity of stem-like gliomaspheres and nonstem glioma cells (obtained at patient neurosurgical resection) were evaluated by clonogenic assays, γ-H 2 AX immunostaining and cell cycle distribution. Survival of irradiated and nonirradiated NOD-SCID mice intracranially implanted with stem-like gliomaspheres were monitored. Glioma cells treated with gefitinib, irradiation, or both were assayed for clonogenic survival, γ-H 2 AX immunostaining, DNA-PKcs expression, and phosphorylation of EGFR and Akt. Results: Stem-like gliomaspheres displayed BTSC characteristics of self-renewal; differentiation into lineages of neurons, oligodendrocytes, and astrocytes; and initiation of glioma growth in NOD-SCID mice. Irradiation dose-dependently reduced clonogenic survival, induced G 2 /M arrest and increased γ-H 2 AX immunostaining of nonstem glioma cells, but not stem-like gliomaspheres. There was no difference in survival of irradiated and nonirradiated mice implanted with stem-like gliomaspheres. The addition of gefitinib significantly inhibited clonogenic survival, increased γ-H 2 AX immunostaining, and reduced DNA-PKcs expression of irradiated stem-like gliomaspheres, without affecting irradiated-nonstem glioma cells. Gefitinib alone, and when combined with irradiation, inhibited phosphorylation of EGFR (Y1068 and Y1045) and Akt (S473) in stem-like gliomaspheres. In nonstem glioma cells, gefitinib alone inhibited EGFR Y1068 phosphorylation, with further inhibition by combined gefitinib and irradiation. Conclusions: Stem-like gliomaspheres are resistant to irradiation

Gefitinib radiosensitizes stem-like glioma cells: inhibition of epidermal growth factor receptor-Akt-DNA-PK signaling, accompanied by inhibition of DNA double-strand break repair.

Science.gov (United States)

Kang, Khong Bee; Zhu, Congju; Wong, Yin Ling; Gao, Qiuhan; Ty, Albert; Wong, Meng Cheong

2012-05-01

We compared radiosensitivity of brain tumor stem cells (BTSCs) with matched nonstem glioma cells, and determined whether gefitinib enhanced BTSC radiosensitivity by inhibiting epidermal growth factor receptor (EGFR)-Akt-DNA-dependent protein kinase (DNA-PK) signaling, followed by enhanced DNA double-stand breaks (DSBs) and inhibition of DSB repair. Radiosensitivity of stem-like gliomaspheres and nonstem glioma cells (obtained at patient neurosurgical resection) were evaluated by clonogenic assays, γ-H(2)AX immunostaining and cell cycle distribution. Survival of irradiated and nonirradiated NOD-SCID mice intracranially implanted with stem-like gliomaspheres were monitored. Glioma cells treated with gefitinib, irradiation, or both were assayed for clonogenic survival, γ-H(2)AX immunostaining, DNA-PKcs expression, and phosphorylation of EGFR and Akt. Stem-like gliomaspheres displayed BTSC characteristics of self-renewal; differentiation into lineages of neurons, oligodendrocytes, and astrocytes; and initiation of glioma growth in NOD-SCID mice. Irradiation dose-dependently reduced clonogenic survival, induced G(2)/M arrest and increased γ-H(2)AX immunostaining of nonstem glioma cells, but not stem-like gliomaspheres. There was no difference in survival of irradiated and nonirradiated mice implanted with stem-like gliomaspheres. The addition of gefitinib significantly inhibited clonogenic survival, increased γ-H(2)AX immunostaining, and reduced DNA-PKcs expression of irradiated stem-like gliomaspheres, without affecting irradiated-nonstem glioma cells. Gefitinib alone, and when combined with irradiation, inhibited phosphorylation of EGFR (Y1068 and Y1045) and Akt (S473) in stem-like gliomaspheres. In nonstem glioma cells, gefitinib alone inhibited EGFR Y1068 phosphorylation, with further inhibition by combined gefitinib and irradiation. Stem-like gliomaspheres are resistant to irradiation-induced cytotoxicity, G(2)/M arrest, and DNA DSBs, compared with nonstem

Gefitinib Radiosensitizes Stem-Like Glioma Cells: Inhibition of Epidermal Growth Factor Receptor-Akt-DNA-PK Signaling, Accompanied by Inhibition of DNA Double-Strand Break Repair

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Kang, Khong Bee, E-mail: dmskkb@nccs.com.sg [Brain Tumour Research Laboratory, Division of Medical Sciences, National Cancer Centre Singapore (Singapore); Zhu Congju; Wong Yinling; Gao Qiuhan; Ty, Albert; Wong, Meng Cheong [Brain Tumour Research Laboratory, Division of Medical Sciences, National Cancer Centre Singapore (Singapore)

2012-05-01

Purpose: We compared radiosensitivity of brain tumor stem cells (BTSCs) with matched nonstem glioma cells, and determined whether gefitinib enhanced BTSC radiosensitivity by inhibiting epidermal growth factor receptor (EGFR)-Akt-DNA-dependent protein kinase (DNA-PK) signaling, followed by enhanced DNA double-stand breaks (DSBs) and inhibition of DSB repair. Methods and Materials: Radiosensitivity of stem-like gliomaspheres and nonstem glioma cells (obtained at patient neurosurgical resection) were evaluated by clonogenic assays, {gamma}-H{sub 2}AX immunostaining and cell cycle distribution. Survival of irradiated and nonirradiated NOD-SCID mice intracranially implanted with stem-like gliomaspheres were monitored. Glioma cells treated with gefitinib, irradiation, or both were assayed for clonogenic survival, {gamma}-H{sub 2}AX immunostaining, DNA-PKcs expression, and phosphorylation of EGFR and Akt. Results: Stem-like gliomaspheres displayed BTSC characteristics of self-renewal; differentiation into lineages of neurons, oligodendrocytes, and astrocytes; and initiation of glioma growth in NOD-SCID mice. Irradiation dose-dependently reduced clonogenic survival, induced G{sub 2}/M arrest and increased {gamma}-H{sub 2}AX immunostaining of nonstem glioma cells, but not stem-like gliomaspheres. There was no difference in survival of irradiated and nonirradiated mice implanted with stem-like gliomaspheres. The addition of gefitinib significantly inhibited clonogenic survival, increased {gamma}-H{sub 2}AX immunostaining, and reduced DNA-PKcs expression of irradiated stem-like gliomaspheres, without affecting irradiated-nonstem glioma cells. Gefitinib alone, and when combined with irradiation, inhibited phosphorylation of EGFR (Y1068 and Y1045) and Akt (S473) in stem-like gliomaspheres. In nonstem glioma cells, gefitinib alone inhibited EGFR Y1068 phosphorylation, with further inhibition by combined gefitinib and irradiation. Conclusions: Stem-like gliomaspheres are

Effects of Transplanted Heparin-Poloxamer Hydrogel Combining Dental Pulp Stem Cells and bFGF on Spinal Cord Injury Repair

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Lihua Luo

2018-01-01

Full Text Available Spinal cord injury (SCI is one of serious traumatic diseases of the central nervous system and has no effective treatment because of its complicated pathophysiology. Tissue engineering strategy which contains scaffolds, cells, and growth factors can provide a promising treatment for SCI. Hydrogel that has 3D network structure and biomimetic microenvironment can support cellular growth and embed biological macromolecules for sustaining release. Dental pulp stem cells (DPSCs, derived from cranial neural crest, possess mesenchymal stem cell (MSC characteristics and have an ability to provide neuroprotective and neurotrophic properties for SCI treatment. Basic fibroblast growth factor (bFGF is able to promote cell survival and proliferation and also has beneficial effect on neural regeneration and functional recovery after SCI. Herein, a thermosensitive heparin-poloxamer (HP hydrogel containing DPSCs and bFGF was prepared, and the effects of HP-bFGF-DPSCs on neuron restoration after SCI were evaluated by functional recovery tests, western blotting, magnetic resonance imaging (MRI, histology evaluation, and immunohistochemistry. The results suggested that transplanted HP hydrogel containing DPSCs and bFGF had a significant impact on spinal cord repair and regeneration and may provide a promising strategy for neuron repair, functional recovery, and tissue regeneration after SCI.

Mesenchymal stem cells for cardiac repair: are the actors ready for the clinical scenario?

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Santiago Roura

2017-10-01

Full Text Available Abstract For years, sufficient progress has been made in treating heart failure following myocardial infarction; however, the social and economic burdens and the costs to world health systems remain high. Moreover, treatment advances have not resolved the underlying problem of functional heart tissue loss. In this field of research, for years we have actively explored innovative biotherapies for cardiac repair. Here, we present a general, critical overview of our experience in using mesenchymal stem cells, derived from cardiac adipose tissue and umbilical cord blood, in a variety of cell therapy and tissue engineering approaches. We also include the latest advances and future challenges, including good manufacturing practice and regulatory issues. Finally, we evaluate whether recent approaches hold potential for reliable translation to clinical trials.

Nucleotide excision repair in differentiated cells

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Wees, Caroline van der [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Department of Cardiology, Leiden University Medical Center, Leiden (Netherlands); Jansen, Jacob [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Vrieling, Harry [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Laarse, Arnoud van der [Department of Cardiology, Leiden University Medical Center, Leiden (Netherlands); Zeeland, Albert van [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Mullenders, Leon [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands)]. E-mail: l.mullenders@lumc.nl

2007-01-03

Nucleotide excision repair (NER) is the principal pathway for the removal of a wide range of DNA helix-distorting lesions and operates via two NER subpathways, i.e. global genome repair (GGR) and transcription-coupled repair (TCR). Although detailed information is available on expression and efficiency of NER in established mammalian cell lines, little is known about the expression of NER pathways in (terminally) differentiated cells. The majority of studies in differentiated cells have focused on repair of UV-induced cyclobutane pyrimidine dimers (CPD) and 6-4-photoproducts (6-4PP) because of the high frequency of photolesions at low level of toxicity and availability of sensitive technologies to determine photolesions in defined regions of the genome. The picture that emerges from these studies is blurred and rather complex. Fibroblasts and terminally differentiated myocytes of the rat heart display equally efficient GGR of 6-4PP but poor repair of CPD due to the absence of p48 expression. This repair phenotype is clearly different from human terminal differentiated neurons. Furthermore, both cell types were found to carry out TCR of CPD, thus mimicking the repair phenotype of established rodent cell lines. In contrast, in intact rat spermatogenic cells repair was very inefficient at the genome overall level and in transcriptionally active genes indicating that GGR and TCR are non-functional. Also, non-differentiated mouse embryonic stem (ES) cells exhibit low levels of NER after UV irradiation. However, the mechanisms that lead to low NER activity are clearly different: in differentiated spermatogenic cells differences in chromatin compaction and sequestering of NER proteins may underlie the lack of NER activity in pre-meiotic cells, whereas in non-differentiated ES cells NER is impaired by a strong apoptotic response.

Treatment Resistance Mechanisms of Malignant Glioma Tumor Stem Cells

International Nuclear Information System (INIS)

Schmalz, Philip G.R.; Shen, Michael J.; Park, John K.

2011-01-01

Malignant gliomas are highly lethal because of their resistance to conventional treatments. Recent evidence suggests that a minor subpopulation of cells with stem cell properties reside within these tumors. These tumor stem cells are more resistant to radiation and chemotherapies than their counterpart differentiated tumor cells and may underlie the persistence and recurrence of tumors following treatment. The various mechanisms by which tumor stem cells avoid or repair the damaging effects of cancer therapies are discussed

Stem cell sources for cardiac regeneration

NARCIS (Netherlands)

Roccio, M.; Goumans, M. J.; Sluijter, J. P. G.; Doevendans, P. A.

Cell-based cardiac repair has the ambitious aim to replace the malfunctioning cardiac muscle developed after myocardial infarction, with new contractile cardiomyocytes and vessels. Different stem cell populations have been intensively studied in the last decade as a potential source of new

Implanted hair follicle stem cells form Schwann cells that support repair of severed peripheral nerves

OpenAIRE

Amoh, Yasuyuki; Li, Lingna; Campillo, Raul; Kawahara, Katsumasa; Katsuoka, Kensei; Penman, Sheldon; Hoffman, Robert M.

2005-01-01

The hair follicle bulge area is an abundant, easily accessible source of actively growing, pluripotent adult stem cells. Nestin, a protein marker for neural stem cells, also is expressed in follicle stem cells and their immediate, differentiated progeny. The fluorescent protein GFP, whose expression is driven by the nestin regulatory element in transgenic mice, served to mark the follicle cell fate. The pluripotent nestin-driven GFP stem cells are positive for the stem cell marker CD34 but ne...

Cellular Mechanisms of Somatic Stem Cell Aging

Science.gov (United States)

Jung, Yunjoon

2014-01-01

Tissue homeostasis and regenerative capacity rely on rare populations of somatic stem cells endowed with the potential to self-renew and differentiate. During aging, many tissues show a decline in regenerative potential coupled with a loss of stem cell function. Cells including somatic stem cells have evolved a series of checks and balances to sense and repair cellular damage to maximize tissue function. However, during aging the mechanisms that protect normal cell function begin to fail. In this review, we will discuss how common cellular mechanisms that maintain tissue fidelity and organismal lifespan impact somatic stem cell function. We will highlight context-dependent changes and commonalities that define aging, by focusing on three age-sensitive stem cell compartments: blood, neural, and muscle. Understanding the interaction between extrinsic regulators and intrinsic effectors that operate within different stem cell compartments is likely to have important implications for identifying strategies to improve health span and treat age-related degenerative diseases. PMID:24439814

Impact of genomic damage and ageing on stem cell function

Science.gov (United States)

Behrens, Axel; van Deursen, Jan M.; Rudolph, K. Lenhard; Schumacher, Björn

2014-01-01

Impairment of stem cell function contributes to the progressive deterioration of tissue maintenance and repair with ageing. Evidence is mounting that age-dependent accumulation of DNA damage in both stem cells and cells that comprise the stem cell microenvironment are partly responsible for stem cell dysfunction with ageing. Here, we review the impact of the various types of DNA damage that accumulate with ageing on stem cell functionality, as well as the development of cancer. We discuss DNA-damage-induced cell intrinsic and extrinsic alterations that influence these processes, and review recent advances in understanding systemic adjustments to DNA damage and how they affect stem cells. PMID:24576896

Role of adipose-derived stem cells in wound healing.

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Hassan, Waqar Ul; Greiser, Udo; Wang, Wenxin

2014-01-01

Impaired wound healing remains a challenge to date and causes debilitating effects with tremendous suffering. Recent advances in tissue engineering approaches in the area of cell therapy have provided promising treatment options to meet the challenges of impaired skin wound healing such as diabetic foot ulcers. Over the last few years, stem cell therapy has emerged as a novel therapeutic approach for various diseases including wound repair and tissue regeneration. Several different types of stem cells have been studied in both preclinical and clinical settings such as bone marrow-derived stem cells, adipose-derived stem cells (ASCs), circulating angiogenic cells (e.g., endothelial progenitor cells), human dermal fibroblasts, and keratinocytes for wound healing. Adipose tissue is an abundant source of mesenchymal stem cells, which have shown an improved outcome in wound healing studies. ASCs are pluripotent stem cells with the ability to differentiate into different lineages and to secrete paracrine factors initiating tissue regeneration process. The abundant supply of fat tissue, ease of isolation, extensive proliferative capacities ex vivo, and their ability to secrete pro-angiogenic growth factors make them an ideal cell type to use in therapies for the treatment of nonhealing wounds. In this review, we look at the pathogenesis of chronic wounds, role of stem cells in wound healing, and more specifically look at the role of ASCs, their mechanism of action and their safety profile in wound repair and tissue regeneration. © 2014 by the Wound Healing Society.

Evolutionary dynamics of adult stem cells: comparison of random and immortal-strand segregation mechanisms.

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Tannenbaum, Emmanuel; Sherley, James L; Shakhnovich, Eugene I

2005-04-01

This paper develops a point-mutation model describing the evolutionary dynamics of a population of adult stem cells. Such a model may prove useful for quantitative studies of tissue aging and the emergence of cancer. We consider two modes of chromosome segregation: (1) random segregation, where the daughter chromosomes of a given parent chromosome segregate randomly into the stem cell and its differentiating sister cell and (2) "immortal DNA strand" co-segregation, for which the stem cell retains the daughter chromosomes with the oldest parent strands. Immortal strand co-segregation is a mechanism, originally proposed by [Cairns Nature (London) 255, 197 (1975)], by which stem cells preserve the integrity of their genomes. For random segregation, we develop an ordered strand pair formulation of the dynamics, analogous to the ordered strand pair formalism developed for quasispecies dynamics involving semiconservative replication with imperfect lesion repair (in this context, lesion repair is taken to mean repair of postreplication base-pair mismatches). Interestingly, a similar formulation is possible with immortal strand co-segregation, despite the fact that this segregation mechanism is age dependent. From our model we are able to mathematically show that, when lesion repair is imperfect, then immortal strand co-segregation leads to better preservation of the stem cell lineage than random chromosome segregation. Furthermore, our model allows us to estimate the optimal lesion repair efficiency for preserving an adult stem cell population for a given period of time. For human stem cells, we obtain that mispaired bases still present after replication and cell division should be left untouched, to avoid potentially fixing a mutation in both DNA strands.

Stem Cell Therapy: An emerging science

International Nuclear Information System (INIS)

Khan, Muhammad M.

2007-01-01

The research on stem cells is advancing knowledge about the development of an organism from a single cell and to how healthy cells replace damaged cells in adult organisms. Stem cell therapy is emerging rapidly nowadays as a technical tool for tissue repair and replacement. The purpose of this review to provide a framework of understanding for the challenges behind translating fundamental stem cell biology and its potential use into clinical therapies, also to give an overview on stem cell research to the scientists of Saudi Arabia in general. English language MEDLINE publications from 1980 through January 2007 for experimental, observational and clinical studies having relation with stem cells with different diseases were reviewed. Approximately 85 publications were reviewed based on the relevance, strength and quality of design and methods, 36 publications were selected for inclusion. Stem cells reside in a specific area of each tissue where they may remain undivided for several years until they are activated by disease or tissue injury. The embryonic stem cells are typically derived from four or five days old embryos and they are pluripotent. The adult tissues reported to contain stem cells brain, bone marrow, peripheral blood, blood vessels, skeletal muscle, skin and liver. The promise of stem cell therapies is an exciting one, but significant technical hurdles remain that will only be overcome through years of intensive research. (author)

Glial origin of mesenchymal stem cells in a tooth model system

NARCIS (Netherlands)

Kaukua, Nina; Shahidi, Maryam Khatibi; Konstantinidou, Chrysoula; Dyachuk, Vyacheslav; Kaucka, Marketa; Furlan, Alessandro; An, Zhengwen; Wang, Longlong; Hultman, Isabell; Ahrlund-Richter, Lars; Blom, Hans; Brismar, Hjalmar; Lopes, Natalia Assaife; Pachnis, Vassilis; Suter, Ueli; Clevers, Hans; Thesleff, Irma; Sharpe, Paul; Ernfors, Patrik; Fried, Kaj; Adameyko, Igor

2014-01-01

Mesenchymal stem cells occupy niches in stromal tissues where they provide sources of cells for specialized mesenchymal derivatives during growth and repair. The origins of mesenchymal stem cells have been the subject of considerable discussion, and current consensus holds that perivascular cells

Multifaceted Roles of Connexin 43 in Stem Cell Niches.

Science.gov (United States)

Genet, Nafiisha; Bhatt, Neha; Bourdieu, Antonin; Hirschi, Karen K

2018-01-01

Considerable progress has been made in the field of stem cell research; nonetheless, the use of stem cells for regenerative medicine therapies, for either endogenous tissue repair or cellular grafts post injury, remains a challenge. To better understand how to maintain stem cell potential in vivo and promote differentiation ex vivo, it is fundamentally important to elucidate the interactions between stem cells and their surrounding partners within their distinct niches. Among the vast array of proteins depicted as mediators for cell-to-cell interactions, connexin-comprised gap junctions play pivotal roles in the regulation of stem cell fate both in vivo and in vitro. This review summarizes and illustrates the current knowledge regarding the multifaceted roles of Cx43, specifically, in various stem cell niches.

Implanted hair follicle stem cells form Schwann cells that support repair of severed peripheral nerves.

Science.gov (United States)

Amoh, Yasuyuki; Li, Lingna; Campillo, Raul; Kawahara, Katsumasa; Katsuoka, Kensei; Penman, Sheldon; Hoffman, Robert M

2005-12-06

The hair follicle bulge area is an abundant, easily accessible source of actively growing, pluripotent adult stem cells. Nestin, a protein marker for neural stem cells, also is expressed in follicle stem cells and their immediate, differentiated progeny. The fluorescent protein GFP, whose expression is driven by the nestin regulatory element in transgenic mice, served to mark the follicle cell fate. The pluripotent nestin-driven GFP stem cells are positive for the stem cell marker CD34 but negative for keratinocyte marker keratin 15, suggesting their relatively undifferentiated state. These cells can differentiate into neurons, glia, keratinocytes, smooth muscle cells, and melanocytes in vitro. In vivo studies show the nestin-driven GFP hair follicle stem cells can differentiate into blood vessels and neural tissue after transplantation to the subcutis of nude mice. Equivalent hair follicle stem cells derived from transgenic mice with beta-actin-driven GFP implanted into the gap region of a severed sciatic nerve greatly enhance the rate of nerve regeneration and the restoration of nerve function. The follicle cells transdifferentiate largely into Schwann cells, which are known to support neuron regrowth. Function of the rejoined sciatic nerve was measured by contraction of the gastrocnemius muscle upon electrical stimulation. After severing the tibial nerve and subsequent transplantation of hair follicle stem cells, walking print length and intermediate toe spread significantly recovered, indicating that the transplanted mice recovered the ability to walk normally. These results suggest that hair follicle stem cells provide an important, accessible, autologous source of adult stem cells for regenerative medicine.

Repair of full-thickness tendon injury using connective tissue progenitors efficiently derived from human embryonic stem cells and fetal tissues.

Science.gov (United States)

Cohen, Shahar; Leshansky, Lucy; Zussman, Eyal; Burman, Michael; Srouji, Samer; Livne, Erella; Abramov, Natalie; Itskovitz-Eldor, Joseph

2010-10-01

The use of stem cells for tissue engineering (TE) encourages scientists to design new platforms in the field of regenerative and reconstructive medicine. Human embryonic stem cells (hESC) have been proposed to be an important cell source for cell-based TE applications as well as an exciting tool for investigating the fundamentals of human development. Here, we describe the efficient derivation of connective tissue progenitors (CTPs) from hESC lines and fetal tissues. The CTPs were significantly expanded and induced to generate tendon tissues in vitro, with ultrastructural characteristics and biomechanical properties typical of mature tendons. We describe a simple method for engineering tendon grafts that can successfully repair injured Achilles tendons and restore the ankle joint extension movement in mice. We also show the CTP's ability to differentiate into bone, cartilage, and fat both in vitro and in vivo. This study offers evidence for the possibility of using stem cell-derived engineered grafts to replace missing tissues, and sets a basic platform for future cell-based TE applications in the fields of orthopedics and reconstructive surgery.

Nanotechnology in the regulation of stem cell behavior

International Nuclear Information System (INIS)

Wu, King-Chuen; Tseng, Ching-Li; Wu, Chi-Chang; Wang, Yang-Kao; Kao, Feng-Chen; Tu, Yuan-Kun; C So, Edmund

2013-01-01

Stem cells are known for their potential to repair damaged tissues. The adhesion, growth and differentiation of stem cells are likely controlled by the surrounding microenvironment which contains both chemical and physical cues. Physical cues in the microenvironment, for example, nanotopography, were shown to play important roles in stem cell fate decisions. Thus, controlling stem cell behavior by nanoscale topography has become an important issue in stem cell biology. Nanotechnology has emerged as a new exciting field and research from this field has greatly advanced. Nanotechnology allows the manipulation of sophisticated surfaces/scaffolds which can mimic the cellular environment for regulating cellular behaviors. Thus, we summarize recent studies on nanotechnology with applications to stem cell biology, including the regulation of stem cell adhesion, growth, differentiation, tracking and imaging. Understanding the interactions of nanomaterials with stem cells may provide the knowledge to apply to cell–scaffold combinations in tissue engineering and regenerative medicine. (review)

Embryos, Clones, and Stem Cells: A Scientific Primer

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Kenyon S. Tweedell

2004-01-01

Full Text Available This article is intended to give the nonspecialist an insight into the nuances of “clones”, cloning, and stem cells. It distinguishes embryonic and adult stem cells, their normal function in the organism, their origin, and how they are recovered to produce stem cell lines in culture. As background, the fundamental processes of embryo development are reviewed and defined, since the manipulation of stem cell lines into desired specialized cells employs many of the same events. Stem cells are defined and characterized and shown how they function in the intact organism during early development and later during cell regeneration in the adult. The complexity of stem cell recovery and their manipulation into specific cells and tissue is illustrated by reviewing current experimentation on both embryonic and adult stem cells in animals and limited research on human stem cell lines. The current and projected use of stem cells for human diseases and repair, along with the expanding methodology for the recovery of human embryonic stem cells, is described. An assessment on the use of human embryonic stem cells is considered from ethical, legal, religious, and political viewpoints.

Stem Cells in Skin Regeneration, Wound Healing, and Their Clinical Applications.

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Ojeh, Nkemcho; Pastar, Irena; Tomic-Canic, Marjana; Stojadinovic, Olivera

2015-10-23

The skin is the largest organ of the body and has an array of functions. Skin compartments, epidermis, and hair follicles house stem cells that are indispensable for skin homeostasis and regeneration. These stem cells also contribute to wound repair, resulting in restoration of tissue integrity and function of damaged tissue. Unsuccessful wound healing processes often lead to non-healing wounds. Chronic wounds are caused by depletion of stem cells and a variety of other cellular and molecular mechanisms, many of which are still poorly understood. Current chronic wound therapies are limited, so the search to develop better therapeutic strategies is ongoing. Adult stem cells are gaining recognition as potential candidates for numerous skin pathologies. In this review, we will discuss epidermal and other stem cells present in the skin, and highlight some of the therapeutic applications of epidermal stem cells and other adult stem cells as tools for cell/scaffold-based therapies for non-healing wounds and other skin disorders. We will also discuss emerging concepts and offer some perspectives on how skin tissue-engineered products can be optimized to provide efficacious therapy in cutaneous repair and regeneration.

Efficient and Fast Differentiation of Human Neural Stem Cells from Human Embryonic Stem Cells for Cell Therapy

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Xinxin Han

2017-01-01

Full Text Available Stem cell-based therapies have been used for repairing damaged brain tissue and helping functional recovery after brain injury. Aberrance neurogenesis is related with brain injury, and multipotential neural stem cells from human embryonic stem (hES cells provide a great promise for cell replacement therapies. Optimized protocols for neural differentiation are necessary to produce functional human neural stem cells (hNSCs for cell therapy. However, the qualified procedure is scarce and detailed features of hNSCs originated from hES cells are still unclear. In this study, we developed a method to obtain hNSCs from hES cells, by which we could harvest abundant hNSCs in a relatively short time. Then, we examined the expression of pluripotent and multipotent marker genes through immunostaining and confirmed differentiation potential of the differentiated hNSCs. Furthermore, we analyzed the mitotic activity of these hNSCs. In this report, we provided comprehensive features of hNSCs and delivered the knowledge about how to obtain more high-quality hNSCs from hES cells which may help to accelerate the NSC-based therapies in brain injury treatment.

Stem cell therapy: the great promise in lung disease.

Science.gov (United States)

Siniscalco, Dario; Sullo, Nikol; Maione, Sabatino; Rossi, Francesco; D'Agostino, Bruno

2008-06-01

Lung injuries are leading causes of morbidity and mortality worldwide. Pulmonary diseases such as asthma or chronic obstructive pulmonary disease characterized by loss of lung elasticity, small airway tethers, and luminal obstruction with inflammatory mucoid secretions, or idiopathic pulmonary fibrosis characterized by excessive matrix deposition and destruction of the normal lung architecture, have essentially symptomatic treatments and their management is costly to the health care system.Regeneration of tissue by stem cells from endogenous, exogenous, and even genetically modified cells is a promising novel therapy. The use of adult stem cells to help with lung regeneration and repair could be a newer technology in clinical and regenerative medicine. In fact, different studies have shown that bone marrow progenitor cells contribute to repair and remodeling of lung in animal models of progressive pulmonary hypertension.Therefore, lung stem cell biology may provide novel approaches to therapy and could represent a great promise for the future of molecular medicine. In fact, several diseases can be slowed or even blocked by stem cell transplantation.

Delayed cell death associated with mitotic catastrophe in γ-irradiated stem-like glioma cells

International Nuclear Information System (INIS)

Firat, Elke; Gaedicke, Simone; Tsurumi, Chizuko; Esser, Norbert; Weyerbrock, Astrid; Niedermann, Gabriele

2011-01-01

Stem-like tumor cells are regarded as highly resistant to ionizing radiation (IR). Previous studies have focused on apoptosis early after irradiation, and the apoptosis resistance observed has been attributed to reduced DNA damage or enhanced DNA repair compared to non-stem tumor cells. Here, early and late radioresponse of patient-derived stem-like glioma cells (SLGCs) and differentiated cells directly derived from them were examined for cell death mode and the influence of stem cell-specific growth factors. Primary SLGCs were propagated in serum-free medium with the stem-cell mitogens epidermal growth factor (EGF) and fibroblast growth factor-2 (FGF-2). Differentiation was induced by serum-containing medium without EGF and FGF. Radiation sensitivity was evaluated by assessing proliferation, clonogenic survival, apoptosis, and mitotic catastrophe. DNA damage-associated γH2AX as well as p53 and p21 expression were determined by Western blots. SLGCs failed to apoptose in the first 4 days after irradiation even at high single doses up to 10 Gy, but we observed substantial cell death later than 4 days postirradiation in 3 of 6 SLGC lines treated with 5 or 10 Gy. This delayed cell death was observed in 3 of the 4 SLGC lines with nonfunctional p53, was associated with mitotic catastrophe and occurred via apoptosis. The early apoptosis resistance of the SLGCs was associated with lower γH2AX compared to differentiated cells, but we found that the stem-cell culture cytokines EGF plus FGF-2 strongly reduce γH2AX levels. Nonetheless, in two p53-deficient SLGC lines examined γIR-induced apoptosis even correlated with EGF/FGF-induced proliferation and mitotic catastrophe. In a line containing CD133-positive and -negative stem-like cells, the CD133-positive cells proliferated faster and underwent more γIR-induced mitotic catastrophe. Our results suggest the importance of delayed apoptosis, associated mitotic catastrophe, and cellular proliferation for γIR-induced death of

Interactions Between Epidermal Keratinocytes, Dendritic Epidermal T-Cells, and Hair Follicle Stem Cells.

Science.gov (United States)

Badarinath, Krithika; Dutta, Abhik; Hegde, Akshay; Pincha, Neha; Gund, Rupali; Jamora, Colin

2018-06-13

The interplay of immune cells and stem cells in maintaining skin homeostasis and repair is an exciting new frontier in cutaneous biology. With the growing appreciation of the importance of this new crosstalk comes the requirement of methods to interrogate the molecular underpinnings of these leukocyte-stem cell interactions. Here we describe how a combination of FACS, cellular coculture assays, and conditioned media treatments can be utilized to advance our understanding of this emerging area of intercellular communication between immune cells and stem cells.

Stem cell therapy to protect and repair the developing brain: a review of mechanisms of action of cord blood and amnion epithelial derived cells

Directory of Open Access Journals (Sweden)

Margie eCastillo-Melendez

2013-10-01

Full Text Available In the research, clinical and wider community there is great interest in the use of stem cells to reduce the progression, or indeed repair brain injury. Perinatal brain injury may result from acute or chronic insults sustained during fetal development, during the process of birth, or in the newborn period. The most readily identifiable outcome of perinatal brain injury is cerebral palsy, however this is just one consequence in a spectrum of mild to severe neurological deficits. As we review, there are now clinical trials taking place worldwide targeting cerebral palsy with stem cell therapies. It will likely be many years before strong evidence-based results emerge from these trials. With such trials underway, it is both appropriate and timely to address the physiological basis for the efficacy of stem-like cells in preventing damage to, or regenerating, the newborn brain. Appropriate experimental animal models are best placed to deliver this information. Cell availability, the potential for immunological rejection, ethical and logistical considerations, together with the propensity for native cells to form terratomas, make it unlikely that embryonic or fetal stem cells will be practical. Fortunately, these issues do not pertain to the use of human amnion epithelial cells (hAECs, or umbilical cord blood (UCB stem cells that are readily and economically obtained from the placenta and umbilical cord discarded at birth. These cells have the potential for transplantation to the newborn where brain injury is diagnosed or even suspected. We will explore the novel characteristics of hAECs and undifferentiated UCB cells, as well as UCB-derived endothelial progenitor cells and mesenchymal stem cells, and how immunomodulation and anti-inflammatory properties are principal mechanisms of action that are common to these cells, and which in turn may ameliorate the cerebral hypoxia and inflammation that are final pathways in the pathogenesis of perinatal brain

Characterizing the radioresponse of pluripotent and multipotent human stem cells.

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Mary L Lan

Full Text Available The potential capability of stem cells to restore functionality to diseased or aged tissues has prompted a surge of research, but much work remains to elucidate the response of these cells to genotoxic agents. To more fully understand the impact of irradiation on different stem cell types, the present study has analyzed the radioresponse of human pluripotent and multipotent stem cells. Human embryonic stem (ES cells, human induced pluripotent (iPS cells, and iPS-derived human neural stem cells (iPS-hNSCs cells were irradiated and analyzed for cell survival parameters, differentiation, DNA damage and repair and oxidative stress at various times after exposure. While irradiation led to dose-dependent reductions in survival, the fraction of surviving cells exhibited dose-dependent increases in metabolic activity. Irradiation did not preclude germ layer commitment of ES cells, but did promote neuronal differentiation. ES cells subjected to irradiation exhibited early apoptosis and inhibition of cell cycle progression, but otherwise showed normal repair of DNA double-strand breaks. Cells surviving irradiation also showed acute and persistent increases in reactive oxygen and nitrogen species that were significant at nearly all post-irradiation times analyzed. We suggest that stem cells alter their redox homeostasis to adapt to adverse conditions and that radiation-induced oxidative stress plays a role in regulating the function and fate of stem cells within tissues compromised by radiation injury.

Mesenchymal stem cells delivered in a microsphere-based engineered skin contribute to cutaneous wound healing and sweat gland repair.

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Huang, Sha; Lu, Gang; Wu, Yan; Jirigala, Enhe; Xu, Yongan; Ma, Kui; Fu, Xiaobing

2012-04-01

Bone-marrow-derived mesenchymal stem cells (BM-MSCs) can contribute to wound healing after skin injury. However, the role of BM-MSCs on repairing skin appendages in renewal tissues is incompletely explored. Moreover, most preclinical studies suggest that the therapeutic effects afforded by BM-MSCs transplantation are short-lived and relatively unstable. To assess whether engrafted bone-marrow-derived mesenchymal stem cells via a delivery system can participate in cutaneous wound healing and sweat-gland repair in mice. For safe and effective delivery of BM-MSCs to wounds, epidermal growth factor (EGF) microspheres were firstly developed to both support cells and maintain appropriate stimuli, then cell-seeded microspheres were incorporated with biomimetic scaffolds and thus fabricated an engineered skin construct with epithelial differentiation and proliferative potential. The applied efficacy was examined by implanting them into excisional wounds on both back and paws of hind legs in mice. After 3 weeks, BM-MSC-engineered skin (EGF loaded) treated wounds exhibited accelerated healing with increased re-epithelialization rates and less skin contraction. Furthermore, histological and immunofluorescence staining analysis revealed sweat glands-like structures became more apparent in BM-MSC-engineered skin (EGF loaded) treated wounds but the number of implanted BM-MSCs were decreased gradually in later phases of healing progression. Our study suggests that BM-MSCs delivered by this EGF microspheres-based engineered skin model may be a promising strategy to repair sweat glands and improve cutaneous wound healing after injury and success in this study might provide a potential benefit for BM-MSCs administration clinically. Copyright © 2012 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Infrapatellar Fat Pad Stem Cells: From Developmental Biology to Cell Therapy

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Ronaldo J. F. C. do Amaral

2017-01-01

Full Text Available The ideal cell type to be used for cartilage therapy should possess a proven chondrogenic capacity, not cause donor-site morbidity, and should be readily expandable in culture without losing their phenotype. There are several cell sources being investigated to promote cartilage regeneration: mature articular chondrocytes, chondrocyte progenitors, and various stem cells. Most recently, stem cells isolated from joint tissue, such as chondrogenic stem/progenitors from cartilage itself, synovial fluid, synovial membrane, and infrapatellar fat pad (IFP have gained great attention due to their increased chondrogenic capacity over the bone marrow and subcutaneous adipose-derived stem cells. In this review, we first describe the IFP anatomy and compare and contrast it with other adipose tissues, with a particular focus on the embryological and developmental aspects of the tissue. We then discuss the recent advances in IFP stem cells for regenerative medicine. We compare their properties with other stem cell types and discuss an ontogeny relationship with other joint cells and their role on in vivo cartilage repair. We conclude with a perspective for future clinical trials using IFP stem cells.

Infrapatellar Fat Pad Stem Cells: From Developmental Biology to Cell Therapy.

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do Amaral, Ronaldo J F C; Almeida, Henrique V; Kelly, Daniel J; O'Brien, Fergal J; Kearney, Cathal J

2017-01-01

The ideal cell type to be used for cartilage therapy should possess a proven chondrogenic capacity, not cause donor-site morbidity, and should be readily expandable in culture without losing their phenotype. There are several cell sources being investigated to promote cartilage regeneration: mature articular chondrocytes, chondrocyte progenitors, and various stem cells. Most recently, stem cells isolated from joint tissue, such as chondrogenic stem/progenitors from cartilage itself, synovial fluid, synovial membrane, and infrapatellar fat pad (IFP) have gained great attention due to their increased chondrogenic capacity over the bone marrow and subcutaneous adipose-derived stem cells. In this review, we first describe the IFP anatomy and compare and contrast it with other adipose tissues, with a particular focus on the embryological and developmental aspects of the tissue. We then discuss the recent advances in IFP stem cells for regenerative medicine. We compare their properties with other stem cell types and discuss an ontogeny relationship with other joint cells and their role on in vivo cartilage repair. We conclude with a perspective for future clinical trials using IFP stem cells.

In Vitro Expansion of Bone Marrow Derived Mesenchymal Stem Cells Alters DNA Double Strand Break Repair of Etoposide Induced DNA Damage

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Ian Hare

2016-01-01

Full Text Available Mesenchymal stem cells (MSCs are of interest for use in diverse cellular therapies. Ex vivo expansion of MSCs intended for transplantation must result in generation of cells that maintain fidelity of critical functions. Previous investigations have identified genetic and phenotypic alterations of MSCs with in vitro passage, but little is known regarding how culturing influences the ability of MSCs to repair double strand DNA breaks (DSBs, the most severe of DNA lesions. To investigate the response to DSB stress with passage in vitro, primary human MSCs were exposed to etoposide (VP16 at various passages with subsequent evaluation of cellular damage responses and DNA repair. Passage number did not affect susceptibility to VP16 or the incidence and repair kinetics of DSBs. Nonhomologous end joining (NHEJ transcripts showed little alteration with VP16 exposure or passage; however, homologous recombination (HR transcripts were reduced following VP16 exposure with this decrease amplified as MSCs were passaged in vitro. Functional evaluations of NHEJ and HR showed that MSCs were unable to activate NHEJ repair following VP16 stress in cells after successive passage. These results indicate that ex vivo expansion of MSCs alters their ability to perform DSB repair, a necessary function for cells intended for transplantation.

In Vitro Expansion of Bone Marrow Derived Mesenchymal Stem Cells Alters DNA Double Strand Break Repair of Etoposide Induced DNA Damage.

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Hare, Ian; Gencheva, Marieta; Evans, Rebecca; Fortney, James; Piktel, Debbie; Vos, Jeffrey A; Howell, David; Gibson, Laura F

2016-01-01

Mesenchymal stem cells (MSCs) are of interest for use in diverse cellular therapies. Ex vivo expansion of MSCs intended for transplantation must result in generation of cells that maintain fidelity of critical functions. Previous investigations have identified genetic and phenotypic alterations of MSCs with in vitro passage, but little is known regarding how culturing influences the ability of MSCs to repair double strand DNA breaks (DSBs), the most severe of DNA lesions. To investigate the response to DSB stress with passage in vitro, primary human MSCs were exposed to etoposide (VP16) at various passages with subsequent evaluation of cellular damage responses and DNA repair. Passage number did not affect susceptibility to VP16 or the incidence and repair kinetics of DSBs. Nonhomologous end joining (NHEJ) transcripts showed little alteration with VP16 exposure or passage; however, homologous recombination (HR) transcripts were reduced following VP16 exposure with this decrease amplified as MSCs were passaged in vitro. Functional evaluations of NHEJ and HR showed that MSCs were unable to activate NHEJ repair following VP16 stress in cells after successive passage. These results indicate that ex vivo expansion of MSCs alters their ability to perform DSB repair, a necessary function for cells intended for transplantation.

Stem cell therapy on skin: Mechanisms, recent advances and drug reviewing issues

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Gong-Yau Chu

2018-01-01

Full Text Available Stem cell products and its clinical applications have been widely discussed in recent years, particularly when the Japanese “induced pluripotent stem cells” founder Dr. Yamanaka was awarded as Nobel Prize laureate in 2013. For decades, major progresses have been achieved in the stem cell biology field, and more and more evidence showed that skin stem cells are involved in the process of skin repair. Stem/progenitor cells of the epidermis are recognized to play the most essential role in the tissue regeneration of skin. In this review, we first illustrated basic stem cell characteristics and various stem cell subtypes resided in the skin. Second, we provided several literatures to elucidate how stem/progenitor cells collaborate in the process of skin repair with the evidence from animal model studies and in vitro experiments. Third, we also introduced several examples of skin cell products on the pharmaceutic market and the ongoing clinical trials aiming for unmet medical difficulties of skin. Last but not least, we summarized general reviewing concerns and some disputatious issues on dermatological cell products. With this concise review, we hope to provide further beneficial suggestions for the development of more effective and safer dermatological stem/progenitor cell products in the future.

Müller stem cell dependent retinal regeneration.

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Chohan, Annu; Singh, Usha; Kumar, Atul; Kaur, Jasbir

2017-01-01

Müller Stem cells to treat ocular diseases has triggered enthusiasm across all medical and scientific communities. Recent development in the field of stem cells has widened the prospects of applying cell based therapies to regenerate ocular tissues that have been irreversibly damaged by disease or injury. Ocular tissues such as the lens and the retina are now known to possess cell having remarkable regenerative abilities. Recent studies have shown that the Müller glia, a cell found in all vertebrate retinas, is the primary source of new neurons, and therefore are considered as the cellular basis for retinal regeneration in mammalian retinas. Here, we review the current status of retinal regeneration of the human eye by Müller stem cells. This review elucidates the current status of retinal regeneration by Müller stem cells, along with major retinal degenerative diseases where these stem cells play regenerative role in retinal repair and replacement. Copyright © 2016. Published by Elsevier B.V.

Stem cell transplantation therapy for multifaceted therapeutic benefits after stroke.

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Wei, Ling; Wei, Zheng Z; Jiang, Michael Qize; Mohamad, Osama; Yu, Shan Ping

2017-10-01

One of the exciting advances in modern medicine and life science is cell-based neurovascular regeneration of damaged brain tissues and repair of neuronal structures. The progress in stem cell biology and creation of adult induced pluripotent stem (iPS) cells has significantly improved basic and pre-clinical research in disease mechanisms and generated enthusiasm for potential applications in the treatment of central nervous system (CNS) diseases including stroke. Endogenous neural stem cells and cultured stem cells are capable of self-renewal and give rise to virtually all types of cells essential for the makeup of neuronal structures. Meanwhile, stem cells and neural progenitor cells are well-known for their potential for trophic support after transplantation into the ischemic brain. Thus, stem cell-based therapies provide an attractive future for protecting and repairing damaged brain tissues after injury and in various disease states. Moreover, basic research on naïve and differentiated stem cells including iPS cells has markedly improved our understanding of cellular and molecular mechanisms of neurological disorders, and provides a platform for the discovery of novel drug targets. The latest advances indicate that combinatorial approaches using cell based therapy with additional treatments such as protective reagents, preconditioning strategies and rehabilitation therapy can significantly improve therapeutic benefits. In this review, we will discuss the characteristics of cell therapy in different ischemic models and the application of stem cells and progenitor cells as regenerative medicine for the treatment of stroke. Copyright © 2017 Elsevier Ltd. All rights reserved.

Isolation, Characterization, and Differentiation of Stem Cells for Cartilage Regeneration

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Beane, Olivia S.; Darling, Eric M.

2012-01-01

The goal of tissue engineering is to create a functional replacement for tissues damaged by injury or disease. In many cases, impaired tissues cannot provide viable cells, leading to the investigation of stem cells as a possible alternative. Cartilage, in particular, may benefit from the use of stem cells since the tissue has low cellularity and cannot effectively repair itself. To address this need, researchers are investigating the chondrogenic capabilities of several multipotent stem cell ...

Clonal analysis of stem cells in differentiation and disease.

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Colom, Bartomeu; Jones, Philip H

2016-12-01

Tracking the fate of individual cells and their progeny by clonal analysis has redefined the concept of stem cells and their role in health and disease. The maintenance of cell turnover in adult tissues is achieved by the collective action of populations of stem cells with an equal likelihood of self-renewal or differentiation. Following injury stem cells exhibit striking plasticity, switching from homeostatic behavior in order to repair damaged tissues. The effects of disease states on stem cells are also being uncovered, with new insights into how somatic mutations trigger clonal expansion in early neoplasia. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

BLM has early and late functions in homologous recombination repair in mouse embryonic stem cells

DEFF Research Database (Denmark)

Chu, W K; Hanada, K; Kanaar, R

2010-01-01

function of BLM remains unclear. Multiple roles have been proposed for BLM in the homologous recombination (HR) repair pathway, including 'early' functions, such as the stimulation of resection of DNA double-strand break ends or displacement of the invading strand of DNA displacement loops, and 'late......' roles, such as dissolution of double Holliday junctions. However, most of the evidence for these putative roles comes from in vitro biochemical data. In this study, we report the characterization of mouse embryonic stem cells with disruption of Blm and/or Rad54 genes. We show that Blm has roles both...

DNA damage responses in human induced pluripotent stem cells and embryonic stem cells.

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Olga Momcilovic

2010-10-01

Full Text Available Induced pluripotent stem (iPS cells have the capability to undergo self-renewal and differentiation into all somatic cell types. Since they can be produced through somatic cell reprogramming, which uses a defined set of transcription factors, iPS cells represent important sources of patient-specific cells for clinical applications. However, before these cells can be used in therapeutic designs, it is essential to understand their genetic stability.Here, we describe DNA damage responses in human iPS cells. We observe hypersensitivity to DNA damaging agents resulting in rapid induction of apoptosis after γ-irradiation. Expression of pluripotency factors does not appear to be diminished after irradiation in iPS cells. Following irradiation, iPS cells activate checkpoint signaling, evidenced by phosphorylation of ATM, NBS1, CHEK2, and TP53, localization of ATM to the double strand breaks (DSB, and localization of TP53 to the nucleus of NANOG-positive cells. We demonstrate that iPS cells temporary arrest cell cycle progression in the G(2 phase of the cell cycle, displaying a lack of the G(1/S cell cycle arrest similar to human embryonic stem (ES cells. Furthermore, both cell types remove DSB within six hours of γ-irradiation, form RAD51 foci and exhibit sister chromatid exchanges suggesting homologous recombination repair. Finally, we report elevated expression of genes involved in DNA damage signaling, checkpoint function, and repair of various types of DNA lesions in ES and iPS cells relative to their differentiated counterparts.High degrees of similarity in DNA damage responses between ES and iPS cells were found. Even though reprogramming did not alter checkpoint signaling following DNA damage, dramatic changes in cell cycle structure, including a high percentage of cells in the S phase, increased radiosensitivity and loss of DNA damage-induced G(1/S cell cycle arrest, were observed in stem cells generated by induced pluripotency.

Potential Role of Dentin Sialoprotein by Inducing Dental Pulp Mesenchymal Stem Cell Differentiation and Mineralization for Dental Tissue Repair

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Zhi Chen

2010-09-01

Full Text Available Introduction: Dentin sialoprotein (DSP is a dentin extracellular matrix protein, a unique marker of dentinogenesis and plays a vital role in odontoblast differentiation and dentin mineralization. Recently, studies have shown that DSP induces differentiation and mineralization of periodontal ligament stem cells and dental papilla mesenchymal cells in vitro and rescues dentin deficiency and increases enamel mineralization in animal models.The hypothesis: DSP as a nature therapeutic agent stimulates dental tissue repair by inducing endogenous dental pulp mesenchymal stem/progenitor cells into odontoblast-like cells to synthesize and to secrete dentin extracellular matrix forming new tertiary dentin as well as to regenerate a functional dentin-pulp complex. As DSP is a nature protein, and clinical procedure for DSP therapy is easy and simple, application of DSP may provide a new avenue for dentists with additional option for the treatment of substantially damaged vital teeth.Evaluation of the hypothesis: Dental caries is the most common dental disease. Deep caries and pulp exposure have been treated by various restorative materials with limited success. One promising approach is dental pulp stem/progenitor-based therapies to regenerate dentin-pulp complex and restore its functions by DSP induction in vivo.

Potential Role of Dentin Sialoprotein by Inducing Dental Pulp Mesenchymal Stem Cell Differentiation and Mineralization for Dental Tissue Repair.

Science.gov (United States)

Yuan, Guo-Hua; Yang, Guo-Bin; Wu, Li-An; Chen, Zhi; Chen, Shuo

2010-01-01

INTRODUCTION: Dentin sialoprotein (DSP) is a dentin extracellular matrix protein, a unique marker of dentinogenesis and plays a vital role in odontoblast differentiation and dentin mineralization. Recently, studies have shown that DSP induces differentiation and mineralization of periodontal ligament stem cells and dental papilla mesenchymal cells in vitro and rescues dentin deficiency and increases enamel mineralization in animal models. THE HYPOTHESIS: DSP as a nature therapeutic agent stimulates dental tissue repair by inducing endogenous dental pulp mesenchymal stem/progenitor cells into odontoblast-like cells to synthesize and to secrete dentin extracellular matrix forming new tertiary dentin as well as to regenerate a functional dentin-pulp complex. As DSP is a nature protein, and clinical procedure for DSP therapy is easy and simple, application of DSP may provide a new avenue for dentists with additional option for the treatment of substantially damaged vital teeth. EVALUATION OF THE HYPOTHESIS: Dental caries is the most common dental disease. Deep caries and pulp exposure have been treated by various restorative materials with limited success. One promising approach is dental pulp stem/progenitor-based therapies to regenerate dentin-pulp complex and restore its functions by DSP induction in vivo.

From regenerative dentistry to regenerative medicine: progress, challenges, and potential applications of oral stem cells

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Xiao L

2014-12-01

Full Text Available Li Xiao,1 Masanori Nasu2 1Department of Pharmacology, 2Research Center, The Nippon Dental University, Tokyo, Japan Abstract: Adult mesenchymal stem cells (MSCs and epithelial stem cells play essential roles in tissue repair and self-healing. Oral MSCs and epithelial stem cells can be isolated from adult human oral tissues, for example, teeth, periodontal ligament, and gingiva. Cocultivated adult oral epithelial stem cells and MSCs could represent some developmental events, such as epithelial invagination and tubular structure formation, signifying their potentials for tissue regeneration. Oral epithelial stem cells have been used in regenerative medicine over 1 decade. They are able to form a stratified cell sheet under three-dimensional culture conditions. Both experimental and clinical data indicate that the cell sheets can not only safely and effectively reconstruct the damaged cornea in humans, but also repair esophageal ulcer in animal models. Oral MSCs include dental pulp stem cells (DPSCs, stem cells from exfoliated deciduous teeth (SHED, stem cells from apical papilla (SCAP, periodontal ligament stem cells (PDLSCs, and mesenchymal stem cells from gingiva (GMSCs. They are widely applied in both regenerative dentistry and medicine. DPSCs, SHED, and SCAP are able to form dentin–pulp complex when being transplanted into immunodeficient animals. They have been experimentally used for the regeneration of dental pulp, neuron, bone muscle and blood vessels in animal models and have shown promising results. PDLSCs and GMSCs are demonstrated to be ideal cell sources for repairing the damaged tissues of periodontal, muscle, and tendon. Despite the abovementioned applications of oral stem cells, only a few human clinical trials are now underway to use them for the treatment of certain diseases. Since clinical use is the end goal, their true regenerative power and safety need to be further examined.Keywords: oral mesenchymal stem cells, oral

Satellite Cells and the Muscle Stem Cell Niche

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Yin, Hang; Price, Feodor

2013-01-01

Adult skeletal muscle in mammals is a stable tissue under normal circumstances but has remarkable ability to repair after injury. Skeletal muscle regeneration is a highly orchestrated process involving the activation of various cellular and molecular responses. As skeletal muscle stem cells, satellite cells play an indispensible role in this process. The self-renewing proliferation of satellite cells not only maintains the stem cell population but also provides numerous myogenic cells, which proliferate, differentiate, fuse, and lead to new myofiber formation and reconstitution of a functional contractile apparatus. The complex behavior of satellite cells during skeletal muscle regeneration is tightly regulated through the dynamic interplay between intrinsic factors within satellite cells and extrinsic factors constituting the muscle stem cell niche/microenvironment. For the last half century, the advance of molecular biology, cell biology, and genetics has greatly improved our understanding of skeletal muscle biology. Here, we review some recent advances, with focuses on functions of satellite cells and their niche during the process of skeletal muscle regeneration. PMID:23303905

On the dynamics of StemBells: Microbubble-conjugated stem cells for ultrasound-controlled delivery

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Kokhuis, Tom J. A.; Naaijkens, Benno A.; Juffermans, Lynda J. M.; Kamp, Otto; van der Steen, Antonius F. W.; Versluis, Michel; de Jong, Nico

2017-07-01

The use of stem cells for regenerative tissue repair is promising but hampered by the low number of cells delivered to the site of injury. To increase the delivery, we propose a technique in which stem cells are linked to functionalized microbubbles, creating echogenic complex dubbed StemBells. StemBells are highly susceptible to acoustic radiation force which can be employed after injection to push the StemBells locally to the treatment site. To optimally benefit from the delivery technique, a thorough characterization of the dynamics of StemBells during ultrasound exposure is needed. Using high-speed optical imaging, we study the dynamics of StemBells as a function of the applied frequency from which resonance curves were constructed. A theoretical model, based on a modified Rayleigh-Plesset type equation, captured the experimental resonance characteristics and radial dynamics in detail.

Fanconi Anemia: A DNA repair disorder characterized by accelerated decline of the hematopoietic stem cell compartment and other features of aging.

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Brosh, Robert M; Bellani, Marina; Liu, Yie; Seidman, Michael M

2017-01-01

Fanconi Anemia (FA) is a rare autosomal genetic disorder characterized by progressive bone marrow failure (BMF), endocrine dysfunction, cancer, and other clinical features commonly associated with normal aging. The anemia stems directly from an accelerated decline of the hematopoietic stem cell compartment. Although FA is a complex heterogeneous disease linked to mutations in 19 currently identified genes, there has been much progress in understanding the molecular pathology involved. FA is broadly considered a DNA repair disorder and the FA gene products, together with other DNA repair factors, have been implicated in interstrand cross-link (ICL) repair. However, in addition to the defective DNA damage response, altered epigenetic regulation, and telomere defects, FA is also marked by elevated levels of inflammatory mediators in circulation, a hallmark of faster decline in not only other hereditary aging disorders but also normal aging. In this review, we offer a perspective of FA as a monogenic accelerated aging disorder, citing the latest evidence for its multi-factorial deficiencies underlying its unique clinical and cellular features. Published by Elsevier B.V.

Stem Cells: New Hope For Spinal Cord Injury

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Gazdic Marina

2015-03-01

Full Text Available Stem cell therapy offers several attractive strategies for spinal cord repair. The regenerative potential of pluripotent stem cells was confirmed in an animal model of Spinal Cord Injury (SCI; nevertheless, optimized growth and differentiation protocols along with reliable safety assays should be established prior to the clinical application of hESCs and iPSCs. Th e therapeutic effects of mesenchymal stem cells (MSCs in SCI result from neurotrophin secretion, angiogenesis, and antiinflammatory actions. Several preclinical SCI studies have reported that the occurrence of axonal extension, remyelination and neuroprotection occur after the transplantation of olfactory ensheathing cells (OECs. The transplantation of neural stem cells NSCs (NSCs promotes partial functional improvement after SCI because of their potential to differentiate into neurons, oligodendrocytes, and astrocytes. The ideal source of stem cells for safe and efficient cell-based therapy for SCI remains a challenging issue that requires further investigation.

Legislation governing pluripotent stem cells in South Africa

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Michael Pepper

2015-09-01

Full Text Available One of the most exciting areas of medical research involves the use of stem cells for the treatment of patients with a variety of diseases and for tissue repair. Although stem cell research is accelerating rapidly in many countries, it has in the past been limited in South Africa (SA; very little has been done in this country to explore the great potential offered by stem cells to address the high disease burden. Stem cell therapy has however been practised for many years, in SA and worldwide, in the form of haematopoietic stem cell transplantation, mainly for haematological malignancies. From a therapeutic perspective, two types of stem cells can be defined: pluripotent stem cells and adult stem cells. Pluripotent cells derived from the inner cell mass of blastocysts (either from in vitro fertilisation or following somatic cell nuclear transfer are called embryonic stem (ES cells, while those derived by reprogramming adult cells are called induced pluripotent stem (iPS cells. Adult stem cells include haematopoietic, mesenchymal and neural stem cells.The purpose of this article is to critically examine the SA legislation with regard to elements that impact on pluripotent stem cell research and the use of pluripotent stem cells for therapeutic purposes. This includes (but is not limited to legislation from the National Health Act (Chapter 8 in particular and its regulations, and deals with matters related to research on embryos in the stem cell context, somatic cell nuclear transfer, reproductive and therapeutic cloning and the generation and therapeutic use of iPS and ES cells.

The suture provides a niche for mesenchymal stem cells of craniofacial bones

Science.gov (United States)

Zhao, Hu; Feng, Jifan; Ho, Thach-Vu; Grimes, Weston; Urata, Mark; Chai, Yang

2015-01-01

Bone tissue undergoes constant turnover supported by stem cells. Recent studies showed that perivascular mesenchymal stem cells (MSCs) contribute to the turnover of long bones. Craniofacial bones are flat bones derived from a different embryonic origin than the long bones. The identity and regulating niche for craniofacial bone MSCs remain unknown. Here, we identify Gli1+ cells within the suture mesenchyme as the major MSC population for craniofacial bones. They are not associated with vasculature, give rise to all craniofacial bones in the adult and are activated during injury repair. Gli1+ cells are typical MSCs in vitro. Ablation of Gli1+ cells leads to craniosynostosis and arrest of skull growth, indicating these cells are an indispensible stem cell population. Twist1+/− mice with craniosynostosis show reduced Gli1+ MSCs in sutures, suggesting that craniosynostosis may result from diminished suture stem cells. Our study indicates that craniofacial sutures provide a unique niche for MSCs for craniofacial bone homeostasis and repair. PMID:25799059

Myocardial regeneration potential of adipose tissue-derived stem cells

Energy Technology Data Exchange (ETDEWEB)

Bai, Xiaowen, E-mail: baixw01@yahoo.com [Department of Molecular Pathology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe, Houston, TX 77030 (United States); Alt, Eckhard, E-mail: ealt@mdanderson.org [Department of Molecular Pathology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe, Houston, TX 77030 (United States)

2010-10-22

Research highlights: {yields} Various tissue resident stem cells are receiving tremendous attention from basic scientists and clinicians and hold great promise for myocardial regeneration. {yields} For practical reasons, human adipose tissue-derived stem cells are attractive stem cells for future clinical application in repairing damaged myocardium. {yields} This review summarizes the characteristics of cultured and freshly isolated stem cells obtained from adipose tissue, their myocardial regeneration potential and the, underlying mechanisms, and safety issues. -- Abstract: Various tissue resident stem cells are receiving attention from basic scientists and clinicians as they hold promise for myocardial regeneration. For practical reasons, adipose tissue-derived stem cells (ASCs) are attractive cells for clinical application in repairing damaged myocardium based on the following advantages: abundant adipose tissue in most patients and easy accessibility with minimally invasive lipoaspiration procedure. Several recent studies have demonstrated that both cultured and freshly isolated ASCs could improve cardiac function in animal model of myocardial infarction. The mechanisms underlying the beneficial effect of ASCs on myocardial regeneration are not fully understood. Growing evidence indicates that transplantation of ASCs improve cardiac function via the differentiation into cardiomyocytes and vascular cells, and through paracrine pathways. Paracrine factors secreted by injected ASCs enhance angiogenesis, reduce cell apoptosis rates, and promote neuron sprouts in damaged myocardium. In addition, Injection of ASCs increases electrical stability of the injured heart. Furthermore, there are no reported cases of arrhythmia or tumorigenesis in any studies regarding myocardial regeneration with ASCs. This review summarizes the characteristics of both cultured and freshly isolated stem cells obtained from adipose tissue, their myocardial regeneration potential, and the

Myocardial regeneration potential of adipose tissue-derived stem cells

International Nuclear Information System (INIS)

Bai, Xiaowen; Alt, Eckhard

2010-01-01

Research highlights: → Various tissue resident stem cells are receiving tremendous attention from basic scientists and clinicians and hold great promise for myocardial regeneration. → For practical reasons, human adipose tissue-derived stem cells are attractive stem cells for future clinical application in repairing damaged myocardium. → This review summarizes the characteristics of cultured and freshly isolated stem cells obtained from adipose tissue, their myocardial regeneration potential and the, underlying mechanisms, and safety issues. -- Abstract: Various tissue resident stem cells are receiving attention from basic scientists and clinicians as they hold promise for myocardial regeneration. For practical reasons, adipose tissue-derived stem cells (ASCs) are attractive cells for clinical application in repairing damaged myocardium based on the following advantages: abundant adipose tissue in most patients and easy accessibility with minimally invasive lipoaspiration procedure. Several recent studies have demonstrated that both cultured and freshly isolated ASCs could improve cardiac function in animal model of myocardial infarction. The mechanisms underlying the beneficial effect of ASCs on myocardial regeneration are not fully understood. Growing evidence indicates that transplantation of ASCs improve cardiac function via the differentiation into cardiomyocytes and vascular cells, and through paracrine pathways. Paracrine factors secreted by injected ASCs enhance angiogenesis, reduce cell apoptosis rates, and promote neuron sprouts in damaged myocardium. In addition, Injection of ASCs increases electrical stability of the injured heart. Furthermore, there are no reported cases of arrhythmia or tumorigenesis in any studies regarding myocardial regeneration with ASCs. This review summarizes the characteristics of both cultured and freshly isolated stem cells obtained from adipose tissue, their myocardial regeneration potential, and the underlying

Involvement of Indian hedgehog signaling in mesenchymal stem cell-augmented rotator cuff tendon repair in an athymic rat model.

Science.gov (United States)

Zong, Jian-Chun; Mosca, Michael J; Degen, Ryan M; Lebaschi, Amir; Carballo, Camila; Carbone, Andrew; Cong, Guang-Ting; Ying, Liang; Deng, Xiang-Hua; Rodeo, Scott A

2017-04-01

Bone marrow aspirate has been used in recent years to augment tendon-to-bone healing, including in rotator cuff repair. However, the healing mechanism in cell-based therapy has not been elucidated in detail. Sixteen athymic nude rats were randomly allocated to 2 groups: experimental (human mesenchymal stem cells in fibrin glue carrier) and control (fibrin glue only). Animals were sacrificed at 2 and 4 weeks. Immunohistochemical staining was performed to evaluate Indian hedgehog (Ihh) signaling and SOX9 signaling in the healing enthesis. Macrophages were identified using CD68 and CD163 staining, and proliferating cells were identified using proliferating cell nuclear antigen staining. More organized and stronger staining for collagen II and a higher abundance of SOX9 + cells were observed at the enthesis in the experimental group at 2 weeks. There was significantly higher Gli1 and Patched1 expression in the experimental group at the enthesis at 2 weeks and higher numbers of Ihh + cells in the enthesis of the experimental group vs control at both 2 weeks and 4 weeks postoperatively. There were more CD68 + cells localized to the tendon midsubstance at 2 weeks compared with 4 weeks, and there was a higher level of CD163 staining in the tendon midsubstance in the experimental group than in the control group at 4 weeks. Stem cell application had a positive effect on fibrocartilage formation at the healing rotator cuff repair site. Both SOX9 and Ihh signaling appear to play an important role in the healing process. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Bone marrow stem cells delivered into the subarachnoid space via cisterna magna improve repair of injured rat spinal cord white matter

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Marcol, Wiesław; Slusarczyk, Wojciech; Sieroń, Aleksander L; Koryciak-Komarska, Halina; Lewin-Kowalik, Joanna

2015-01-01

The influence of bone marrow stem cells on regeneration of spinal cord in rats was investigated. Young adult male Wistar rats were used (n=22). Focal injury of spinal cord white matter at Th10 level was produced using our original non-laminectomy method by means of high-pressured air stream. Cells from tibial and femoral bone marrow of 1-month old rats (n=3) were cultured, labeled with BrdU/Hoechst and injected into cisterna magna (experimental group) three times: immediately after spinal cord injury and 3 as well as 7 days later. Neurons in brain stem and motor cortex were labeled with FluoroGold (FG) delivered caudally from the injury site a week before the end of experiment. Functional outcome and morphological features of regeneration were analyzed during 12-week follow-up. The lesions were characterized by means of MRI. Maximal distance of expansion of implanted cells in the spinal cord was measured and the number of FG-positive neurons in the brain was counted. Rats treated with stem cells presented significant improvement of locomotor performance and spinal cord morphology when compared to the control group. Distance covered by stem cells was 7 mm from the epicenter of the injury. Number of brain stem and motor cortex FG-positive neurons in experimental group was significantly higher than in control. Obtained data showed that bone marrow stem cells are able to induce the repair of injured spinal cord white matter. The route of cells application via cisterna magna appeared to be useful for their delivery in spinal cord injury therapy. PMID:26628950

Regenerating the injured kidney with human umbilical cord mesenchymal stem cell-derived exosomes

OpenAIRE

Dorronsoro, Akaitz; Robbins, Paul D

2013-01-01

Transplantation of adult stem cells is being used to facilitate repair or regeneration of damaged or diseased tissues. However, in many cases, the therapeutic effects of the injected stem cells are mediated by factors secreted by stem cells and not by differentiation of the transplanted stem cells. Recent reports have identified a class of microvesicles, termed exosomes, released by stem cells that are able to confer therapeutic effects on injured renal and cardiac tissue. In this issue of St...

Rejuvenating Strategies for Stem Cell-based Therapies in Aging

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Neves, Joana; Sousa-Victor, Pedro; Jasper, Heinrich

2017-01-01

SUMMARY Recent advances in our understanding of tissue regeneration and the development of efficient approaches to induce and differentiate pluripotent stem cells for cell replacement therapies promise exciting avenues for treating degenerative age-related diseases. However, clinical studies and insights from model organisms have identified major roadblocks that normal aging processes impose on tissue regeneration. These new insights suggest that specific targeting of environmental niche components, including growth factors, ECM and immune cells, and intrinsic stem cell properties that are affected by aging will be critical for development of new strategies to improve stem cell function and optimize tissue repair processes. PMID:28157498

Mesenchymal Stem Cells Retain Their Defining Stem Cell Characteristics After Exposure to Ionizing Radiation

International Nuclear Information System (INIS)

Nicolay, Nils H.; Sommer, Eva; Lopez, Ramon; Wirkner, Ute; Trinh, Thuy; Sisombath, Sonevisay; Debus, Jürgen; Ho, Anthony D.; Saffrich, Rainer; Huber, Peter E.

2013-01-01

Purpose: Mesenchymal stem cells (MSCs) have the ability to migrate to lesion sites and undergo differentiation into functional tissues. Although this function may be important for tissue regeneration after radiation therapy, the influence of ionizing radiation (IR) on cellular survival and the functional aspects of differentiation and stem cell characteristics of MSCs have remained largely unknown. Methods and Materials: Radiation sensitivity of human primary MSCs from healthy volunteers and primary human fibroblast cells was examined, and cellular morphology, cell cycle effects, apoptosis, and differentiation potential after exposure to IR were assessed. Stem cell gene expression patterns after exposure to IR were studied using gene arrays. Results: MSCs were not more radiosensitive than human primary fibroblasts, whereas there were considerable differences regarding radiation sensitivity within individual MSCs. Cellular morphology, cytoskeletal architecture, and cell motility were not markedly altered by IR. Even after high radiation doses up to 10 Gy, MSCs maintained their differentiation potential. Compared to primary fibroblast cells, MSCs did not show an increase in irradiation-induced apoptosis. Gene expression analyses revealed an upregulation of various genes involved in DNA damage response and DNA repair, but expression of established MSC surface markers appeared only marginally influenced by IR. Conclusions: These data suggest that human MSCs are not more radiosensitive than differentiated primary fibroblasts. In addition, upon photon irradiation, MSCs were able to retain their defining stem cell characteristics both on a functional level and regarding stem cell marker expression

Sources of adult mesenchymal stem cells for ligament and tendon tissue engineering.

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Dhinsa, Baljinder S; Mahapatra, Anant N; Khan, Wasim S

2015-01-01

Tendon and ligament injuries are common, and repair slowly with reduced biomechanical properties. With increasing financial demands on the health service and patients to recover from tendon and ligament injuries faster, and with less morbidity, health professionals are exploring new treatment options. Tissue engineering may provide the answer, with its unlimited source of natural cells that in the correct environment may improve repair and regeneration of tendon and ligament tissue. Mesenchymal stem cells have demonstrated the ability to self renew and have multilineage differentiation potential. The use of bone marrow-derived mesenchymal stem cells has been reported, however significant in vitro culture expansion is required due to the low yield of cells, which has financial implications. Harvesting of bone marrow cells also has associated morbidity. Several studies have looked at alternative sources for mesenchymal stem cells. Reports in literature from animal studies have been encouraging, however further work is required. This review assesses the potential sources of mesenchymal stem cells for tissue engineering in tendons and ligaments.

The clinical application of mesenchymal stromal cells in hematopoietic stem cell transplantation

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Ke Zhao

2016-05-01

Full Text Available Abstract Mesenchymal stromal cells (MSCs are multipotent stem cells well known for repairing tissue, supporting hematopoiesis, and modulating immune and inflammation response. These outstanding properties make MSCs as an attractive candidate for cellular therapy in immune-based disorders, especially hematopoietic stem cell transplantation (HSCT. In this review, we outline the progress of MSCs in preventing and treating engraftment failure (EF, graft-versus-host disease (GVHD following HSCT and critically discuss unsolved issues in clinical applications.

Transplanted Human Umbilical Cord Mesenchymal Stem Cells Facilitate Lesion Repair in B6.Fas Mice

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Guang-ping Ruan

2014-01-01

Full Text Available Background. Systemic lupus erythematosus (SLE is a multisystem disease that is characterized by the appearance of serum autoantibodies. No effective treatment for SLE currently exists. Methods. We used human umbilical cord mesenchymal stem cell (H-UC-MSC transplantation to treat B6.Fas mice. Results. After four rounds of cell transplantation, we observed a statistically significant decrease in the levels of mouse anti-nuclear, anti-histone, and anti-double-stranded DNA antibodies in transplanted mice compared with controls. The percentage of CD4+CD25+Foxp3+ T cells in mouse peripheral blood significantly increased after H-UC-MSC transplantation. Conclusions. The results showed that H-UC-MSCs could repair lesions in B6.Fas mice such that all of the relevant disease indicators in B6.Fas mice were restored to the levels observed in normal C57BL/6 mice.

TAK1 modulates satellite stem cell homeostasis and skeletal muscle repair

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Ogura, Yuji; Hindi, Sajedah M.; Sato, Shuichi; Xiong, Guangyan; Akira, Shizuo; Kumar, Ashok

2015-01-01

Satellite cells are resident adult stem cells that are required for regeneration of skeletal muscle. However, signalling mechanisms that regulate satellite cell function are less understood. Here we demonstrate that transforming growth factor-β-activated kinase 1 (TAK1) is important in satellite stem cell homeostasis and function. Inactivation of TAK1 in satellite cells inhibits muscle regeneration in adult mice. TAK1 is essential for satellite cell proliferation and its inactivation causes precocious differentiation. Moreover, TAK1-deficient satellite cells exhibit increased oxidative stress and undergo spontaneous cell death, primarily through necroptosis. TAK1 is required for the activation of NF-κB and JNK in satellite cells. Forced activation of NF-κB improves survival and proliferation of TAK1-deficient satellite cells. Furthermore, TAK1-mediated activation of JNK is essential to prevent oxidative stress and precocious differentiation of satellite cells. Collectively, our study suggests that TAK1 is required for maintaining the pool of satellite stem cells and for regenerative myogenesis. PMID:26648529

Autologous hematopoietic stem cell transplantation in lymphoma patients is associated with a decrease in the double strand break repair capacity of peripheral blood lymphocytes.

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Lacoste, Sandrine; Bhatia, Smita; Chen, Yanjun; Bhatia, Ravi; O'Connor, Timothy R

2017-01-01

Patients who undergo autologous hematopoietic stem cell transplantation (aHCT) for treatment of a relapsed or refractory lymphoma are at risk of developing therapy related- myelodysplasia/acute myeloid leukemia (t-MDS/AML). Part of the risk likely resides in inherent interindividual differences in their DNA repair capacity (DRC), which is thought to influence the effect chemotherapeutic treatments have on the patient's stem cells prior to aHCT. Measuring DRC involves identifying small differences in repair proficiency among individuals. Initially, we investigated the cell model in healthy individuals (primary lymphocytes and/or lymphoblastoid cell lines) that would be appropriate to measure genetically determined DRC using host-cell reactivation assays. We present evidence that interindividual differences in DRC double-strand break repair (by non-homologous end-joining [NHEJ] or single-strand annealing [SSA]) are better preserved in non-induced primary lymphocytes. In contrast, lymphocytes induced to proliferate are required to assay base excision (BER) or nucleotide excision repair (NER). We established that both NHEJ and SSA DRCs in lymphocytes of healthy individuals were inversely correlated with the age of the donor, indicating that DSB repair in lymphocytes is likely not a constant feature but rather something that decreases with age (~0.37% NHEJ DRC/year). To investigate the predictive value of pre-aHCT DRC on outcome in patients, we then applied the optimized assays to the analysis of primary lymphocytes from lymphoma patients and found that individuals who later developed t-MDS/AML (cases) were indistinguishable in their DRC from controls who never developed t-MDS/AML. However, when DRC was investigated shortly after aHCT in the same individuals (21.6 months later on average), aHCT patients (both cases and controls) showed a significant decrease in DSB repair measurements. The average decrease of 6.9% in NHEJ DRC observed among aHCT patients was much higher

Autologous hematopoietic stem cell transplantation in lymphoma patients is associated with a decrease in the double strand break repair capacity of peripheral blood lymphocytes.

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Sandrine Lacoste

Full Text Available Patients who undergo autologous hematopoietic stem cell transplantation (aHCT for treatment of a relapsed or refractory lymphoma are at risk of developing therapy related- myelodysplasia/acute myeloid leukemia (t-MDS/AML. Part of the risk likely resides in inherent interindividual differences in their DNA repair capacity (DRC, which is thought to influence the effect chemotherapeutic treatments have on the patient's stem cells prior to aHCT. Measuring DRC involves identifying small differences in repair proficiency among individuals. Initially, we investigated the cell model in healthy individuals (primary lymphocytes and/or lymphoblastoid cell lines that would be appropriate to measure genetically determined DRC using host-cell reactivation assays. We present evidence that interindividual differences in DRC double-strand break repair (by non-homologous end-joining [NHEJ] or single-strand annealing [SSA] are better preserved in non-induced primary lymphocytes. In contrast, lymphocytes induced to proliferate are required to assay base excision (BER or nucleotide excision repair (NER. We established that both NHEJ and SSA DRCs in lymphocytes of healthy individuals were inversely correlated with the age of the donor, indicating that DSB repair in lymphocytes is likely not a constant feature but rather something that decreases with age (~0.37% NHEJ DRC/year. To investigate the predictive value of pre-aHCT DRC on outcome in patients, we then applied the optimized assays to the analysis of primary lymphocytes from lymphoma patients and found that individuals who later developed t-MDS/AML (cases were indistinguishable in their DRC from controls who never developed t-MDS/AML. However, when DRC was investigated shortly after aHCT in the same individuals (21.6 months later on average, aHCT patients (both cases and controls showed a significant decrease in DSB repair measurements. The average decrease of 6.9% in NHEJ DRC observed among aHCT patients was

Proteomics in studying cancer stem cell biology.

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Kranenburg, Onno; Emmink, Benjamin L; Knol, Jaco; van Houdt, Winan J; Rinkes, Inne H M Borel; Jimenez, Connie R

2012-06-01

Normal multipotent tissue stem cells (SCs) are the driving force behind tissue turnover and repair. The cancer stem cell theory holds that tumors also contain stem-like cells that drive tumor growth and metastasis formation. However, very little is known about the regulation of SC maintenance pathways in cancer and how these are affected by cancer-specific genetic alterations and by treatment. Proteomics is emerging as a powerful tool to identify the signaling complexes and pathways that control multi- and pluri-potency and SC differentiation. Here, the authors review the novel insights that these studies have provided and present a comprehensive strategy for the use of proteomics in studying cancer SC biology.

Functional dysregulation of stem cells during aging: a focus on skeletal muscle stem cells.

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García-Prat, Laura; Sousa-Victor, Pedro; Muñoz-Cánoves, Pura

2013-09-01

Aging of an organism is associated with the functional decline of tissues and organs, as well as a sharp decline in the regenerative capacity of stem cells. A prevailing view holds that the aging rate of an individual depends on the ratio of tissue attrition to tissue regeneration. Therefore, manipulations that favor the balance towards regeneration may prevent or delay aging. Skeletal muscle is a specialized tissue composed of postmitotic myofibers that contract to generate force. Satellite cells are the adult stem cells responsible for skeletal muscle regeneration. Recent studies on the biology of skeletal muscle and satellite cells in aging have uncovered the critical impact of systemic and niche factors on stem cell functionality and demonstrated the capacity of aged satellite cells to rejuvenate and increase their regenerative potential when exposed to a youthful environment. Here we review the current literature on the coordinated relationship between cell extrinsic and intrinsic factors that regulate the function of satellite cells, and ultimately determine tissue homeostasis and repair during aging, and which encourage the search for new anti-aging strategies. © 2013 The Authors Journal compilation © 2013 FEBS.

Natural Type II Collagen Hydrogel, Fibrin Sealant, and Adipose-Derived Stem Cells as a Promising Combination for Articular Cartilage Repair.

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Lazarini, Mariana; Bordeaux-Rego, Pedro; Giardini-Rosa, Renata; Duarte, Adriana S S; Baratti, Mariana Ozello; Zorzi, Alessandro Rozim; de Miranda, João Batista; Lenz Cesar, Carlos; Luzo, Ângela; Olalla Saad, Sara Teresinha

2017-10-01

Objective Articular cartilage is an avascular tissue with limited ability of self-regeneration and the current clinical treatments have restricted capacity to restore damages induced by trauma or diseases. Therefore, new techniques are being tested for cartilage repair, using scaffolds and/or stem cells. Although type II collagen hydrogel, fibrin sealant, and adipose-derived stem cells (ASCs) represent suitable alternatives for cartilage formation, their combination has not yet been investigated in vivo for focal articular cartilage defects. We performed a simple experimental procedure using the combination of these 3 compounds on cartilage lesions of rabbit knees. Design The hydrogel was developed in house and was first tested in vitro for chondrogenic differentiation. Next, implants were performed in chondral defects with or without ASCs and the degree of regeneration was macroscopically and microscopically evaluated. Results Production of proteoglycans and the increased expression of collagen type II (COL2α1), aggrecan (ACAN), and sex-determining region Y-box 9 (SOX9) confirmed the chondrogenic character of ASCs in the hydrogel in vitro. Importantly, the addition of ASC induced a higher overall repair of the chondral lesions and a better cellular organization and collagen fiber alignment compared with the same treatment without ASCs. This regenerating tissue also presented the expression of cartilage glycosaminoglycan and type II collagen. Conclusions Our results indicate that the combination of the 3 compounds is effective for articular cartilage repair and may be of future clinical interest.

Umbilical cord-derived mesenchymal stem cell transplantation combined with hyperbaric oxygen treatment for repair of traumatic brain injury

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Zhou, Hai-xiao; Liu, Zhi-gang; Liu, Xiao-jiao; Chen, Qian-xue

2016-01-01

Transplantation of umbilical cord-derived mesenchymal stem cells (UC-MSCs) for repair of traumatic brain injury has been used in the clinic. Hyperbaric oxygen (HBO) treatment has long been widely used as an adjunctive therapy for treating traumatic brain injury. UC-MSC transplantation combined with HBO treatment is expected to yield better therapeutic effects on traumatic brain injury. In this study, we established rat models of severe traumatic brain injury by pressurized fluid (2.5–3.0 atm impact force). The injured rats were then administered UC-MSC transplantation via the tail vein in combination with HBO treatment. Compared with monotherapy, aquaporin 4 expression decreased in the injured rat brain, but growth-associated protein-43 expression, calaxon-like structures, and CM-Dil-positive cell number increased. Following combination therapy, however, rat cognitive and neurological function significantly improved. UC-MSC transplantation combined with HBO therapyfor repair of traumatic brain injury shows better therapeutic effects than monotherapy and significantly promotes recovery of neurological functions. PMID:26981097

Umbilical cord-derived mesenchymal stem cell transplantation combined with hyperbaric oxygen treatment for repair of traumatic brain injury

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Hai-xiao Zhou

2016-01-01

Full Text Available Transplantation of umbilical cord-derived mesenchymal stem cells (UC-MSCs for repair of traumatic brain injury has been used in the clinic. Hyperbaric oxygen (HBO treatment has long been widely used as an adjunctive therapy for treating traumatic brain injury. UC-MSC transplantation combined with HBO treatment is expected to yield better therapeutic effects on traumatic brain injury. In this study, we established rat models of severe traumatic brain injury by pressurized fluid (2.5-3.0 atm impact force. The injured rats were then administered UC-MSC transplantation via the tail vein in combination with HBO treatment. Compared with monotherapy, aquaporin 4 expression decreased in the injured rat brain, but growth-associated protein-43 expression, calaxon-like structures, and CM-Dil-positive cell number increased. Following combination therapy, however, rat cognitive and neurological function significantly improved. UC-MSC transplantation combined with HBO therapyfor repair of traumatic brain injury shows better therapeutic effects than monotherapy and significantly promotes recovery of neurological functions.

Honey can repairing damage of liver tissue due to protein energy malnutrition through induction of endogenous stem cells.

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Prasetyo, R Heru; Hestianah, Eka Pramyrtha

2017-06-01

This study was to evaluate effect of honey in repairing damage of liver tissue due to energy protein malnutrition and in mobilization of endogenous stem cells. Male mice model of degenerative liver was obtained through food fasting but still have drinking water for 5 days. It caused energy protein malnutrition and damage of liver tissue. The administration of 50% (v/v) honey was performed for 10 consecutive days, while the positive control group was fasted and not given honey and the negative control not fasted and without honey. Observations of regeneration the liver tissue based on histologically examination, observation of Hsp70 expression, and homing signal based on vascular endothelial growth factor-1 (VEGF-1) expression using immunohistochemistry technique. Observation on expression of CD34 and CD45 as the marker of auto mobilization of hematopoietic stem cells using flow cytometry technique. There is regeneration of the liver tissue due to protein energy malnutrition, decrease of Hsp70 expression, increase of VEGF-1 expression, and high expression of CD34 and CD45. Honey can improve the liver tissue based on: (1) Mobilization of endogenous stem cells (CD34 and CD45); (2) Hsp70 and VEGF-1 expressions as regeneration marker of improvement, and (3) regeneration histologically of liver tissue.

Bone marrow stromal cell : mediated neuroprotection for spinal cord repair

NARCIS (Netherlands)

Ritfeld, Gaby Jane

2014-01-01

Currently, there is no treatment available that restores anatomy and function after spinal cord injury. This thesis explores transplantation of bone marrow-derived mesenchymal stem cells (bone marrow stromal cells; BMSCs) as a therapeutic approach for spinal cord repair. BMSCs secrete neurotrophic

Stem Cells for Skeletal Muscle Tissue Engineering.

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Pantelic, Molly N; Larkin, Lisa M

2018-04-19

Volumetric muscle loss (VML) is a debilitating condition wherein muscle loss overwhelms the body's normal physiological repair mechanism. VML is particularly common among military service members who have sustained war injuries. Because of the high social and medical cost associated with VML and suboptimal current surgical treatments, there is great interest in developing better VML therapies. Skeletal muscle tissue engineering (SMTE) is a promising alternative to traditional VML surgical treatments that use autogenic tissue grafts, and rather uses isolated stem cells with myogenic potential to generate de novo skeletal muscle tissues to treat VML. Satellite cells are the native precursors to skeletal muscle tissue, and are thus the most commonly studied starting source for SMTE. However, satellite cells are difficult to isolate and purify, and it is presently unknown whether they would be a practical source in clinical SMTE applications. Alternative myogenic stem cells, including adipose-derived stem cells, bone marrow-derived mesenchymal stem cells, perivascular stem cells, umbilical cord mesenchymal stem cells, induced pluripotent stem cells, and embryonic stem cells, each have myogenic potential and have been identified as possible starting sources for SMTE, although they have yet to be studied in detail for this purpose. These alternative stem cell varieties offer unique advantages and disadvantages that are worth exploring further to advance the SMTE field toward highly functional, safe, and practical VML treatments. The following review summarizes the current state of satellite cell-based SMTE, details the properties and practical advantages of alternative myogenic stem cells, and offers guidance to tissue engineers on how alternative myogenic stem cells can be incorporated into SMTE research.

Umbilical Cord-Derived Mesenchymal Stem Cells for Hematopoietic Stem Cell Transplantation

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Yu-Hua Chao

2012-01-01

Full Text Available Hematopoietic stem cell transplantation (HSCT is becoming an effective therapeutic modality for a variety of diseases. Mesenchymal stem cells (MSCs can be used to enhance hematopoietic engraftment, accelerate lymphocyte recovery, reduce the risk of graft failure, prevent and treat graft-versus-host disease, and repair tissue damage in patients receiving HSCT. Till now, most MSCs for human clinical application have been derived from bone marrow. However, acquiring bone-marrow-derived MSCs involves an invasive procedure. Umbilical cord is rich with MSCs. Compared to bone-marrow-derived MSCs, umbilical cord-derived MSCs (UCMSCs are easier to obtain without harm to the donor and can proliferate faster. No severe adverse effects were noted in our previous clinical application of UCMSCs in HSCT. Accordingly, application of UCMSCs in humans appears to be feasible and safe. Further studies are warranted.

Effectiveness of mesenchymal stems cells cultured by hanging drop vs. conventional culturing on the repair of hypoxic-ischemic-damaged mouse brains, measured by stemness gene expression

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Lou Yongli

2016-01-01

Full Text Available In this study, we investigated the therapeutic effects of Human Mesenchymal Stem Cells (hMSCs cultured by hanging drop and conventional culturing methods on cerebellar repair in hypoxic-ischemic (HI brain injured mice. Real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR was used to analyze the expression levels of three stemness genes, Oct4, Sox2 and Nanog, and the migration related gene CXCR4. MSC prepared by hanging drop or conventional techniques were administered intranasally to nine day old mice, and analyzed by MRI at day 28. Results indicate that the MSCs, especially the hanging drop cultured MSCs, significantly improved the mice’s cerebellar damage repair. MSCs derived from the hanging drop culture were smaller than those from the conventional culture. The gene expression levels were significantly increased for the MSCs derived from the hanging drop culture. The mechanism might relate to the fact that the hanging drop cultured MSCs can be kept in an undifferentiated state, resulting in its higher expression level of migration receptor of CXCR4.

The Need to Study, Mimic, and Target Stem Cell Niches

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Vishwakarma, Ajaykumar; Rouwkema, Jeroen; Jones, Peter Anthony; Karp, Jeffrey M.; Vishwakarma, Ajaykumar; Karp, Jeffrey M.

2017-01-01

Despite important advances in tissue repair and regeneration over the past few decades, complete functional repair of damaged or diseased human tissues has remained elusive. Recent discoveries in stem cell niche molecular biology and biomaterials engineering may hold the key to true regeneration.

Stem cell treatment of degenerative eye disease

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Ben Mead

2015-05-01

Full Text Available Stem cell therapies are being explored extensively as treatments for degenerative eye disease, either for replacing lost neurons, restoring neural circuits or, based on more recent evidence, as paracrine-mediated therapies in which stem cell-derived trophic factors protect compromised endogenous retinal neurons from death and induce the growth of new connections. Retinal progenitor phenotypes induced from embryonic stem cells/induced pluripotent stem cells (ESCs/iPSCs and endogenous retinal stem cells may replace lost photoreceptors and retinal pigment epithelial (RPE cells and restore vision in the diseased eye, whereas treatment of injured retinal ganglion cells (RGCs has so far been reliant on mesenchymal stem cells (MSC. Here, we review the properties of non-retinal-derived adult stem cells, in particular neural stem cells (NSCs, MSC derived from bone marrow (BMSC, adipose tissues (ADSC and dental pulp (DPSC, together with ESC/iPSC and discuss and compare their potential advantages as therapies designed to provide trophic support, repair and replacement of retinal neurons, RPE and glia in degenerative retinal diseases. We conclude that ESCs/iPSCs have the potential to replace lost retinal cells, whereas MSC may be a useful source of paracrine factors that protect RGC and stimulate regeneration of their axons in the optic nerve in degenerate eye disease. NSC may have potential as both a source of replacement cells and also as mediators of paracrine treatment.

Stem cell treatment of degenerative eye disease.

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Mead, Ben; Berry, Martin; Logan, Ann; Scott, Robert A H; Leadbeater, Wendy; Scheven, Ben A

2015-05-01

Stem cell therapies are being explored extensively as treatments for degenerative eye disease, either for replacing lost neurons, restoring neural circuits or, based on more recent evidence, as paracrine-mediated therapies in which stem cell-derived trophic factors protect compromised endogenous retinal neurons from death and induce the growth of new connections. Retinal progenitor phenotypes induced from embryonic stem cells/induced pluripotent stem cells (ESCs/iPSCs) and endogenous retinal stem cells may replace lost photoreceptors and retinal pigment epithelial (RPE) cells and restore vision in the diseased eye, whereas treatment of injured retinal ganglion cells (RGCs) has so far been reliant on mesenchymal stem cells (MSC). Here, we review the properties of non-retinal-derived adult stem cells, in particular neural stem cells (NSCs), MSC derived from bone marrow (BMSC), adipose tissues (ADSC) and dental pulp (DPSC), together with ESC/iPSC and discuss and compare their potential advantages as therapies designed to provide trophic support, repair and replacement of retinal neurons, RPE and glia in degenerative retinal diseases. We conclude that ESCs/iPSCs have the potential to replace lost retinal cells, whereas MSC may be a useful source of paracrine factors that protect RGC and stimulate regeneration of their axons in the optic nerve in degenerate eye disease. NSC may have potential as both a source of replacement cells and also as mediators of paracrine treatment. Copyright © 2015. Published by Elsevier B.V.

Microencapsulation of Stem Cells for Therapy.

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Leslie, Shirae K; Kinney, Ramsey C; Schwartz, Zvi; Boyan, Barbara D

2017-01-01

An increasing demand to regenerate tissues from patient-derived sources has led to the development of cell-based therapies using autologous stem cells, thereby decreasing immune rejection of scaffolds coupled with allogeneic stem cells or allografts. Adult stem cells are multipotent and are readily available in tissues such as fat and bone marrow. They possess the ability to repair and regenerate tissue through the production of therapeutic factors, particularly vasculogenic proteins. A major challenge in cell-based therapies is localizing the delivered stem cells to the target site. Microencapsulation of cells provides a porous polymeric matrix that can provide a protected environment, localize the cells to one area, and maintain their viability by enabling the exchange of nutrients and waste products between the encapsulated cells and the surrounding tissue. In this chapter, we describe a method to produce injectable microbeads containing a tunable number of stem cells using the biopolymer alginate. The microencapsulation process involves extrusion of the alginate suspension containing cells from a microencapsulator, a syringe pump to control its flow rate, an electrostatic potential to overcome capillary forces and a reduced Ca ++ cross-linking solution containing a nutrient osmolyte, to form microbeads. This method allows the encapsulated cells to remain viable up to three weeks in culture and up to three months in vivo and secrete growth factors capable of supporting tissue regeneration.

Perspectives of purinergic signaling in stem cell differentiation and tissue regeneration.

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Glaser, Talita; Cappellari, Angélica Regina; Pillat, Micheli Mainardi; Iser, Isabele Cristiana; Wink, Márcia Rosângela; Battastini, Ana Maria Oliveira; Ulrich, Henning

2012-09-01

Replacement of lost or dysfunctional tissues by stem cells has recently raised many investigations on therapeutic applications. Purinergic signaling has been shown to regulate proliferation, differentiation, cell death, and successful engraftment of stem cells originated from diverse origins. Adenosine triphosphate release occurs in a controlled way by exocytosis, transporters, and lysosomes or in large amounts from damaged cells, which is then subsequently degraded into adenosine. Paracrine and autocrine mechanisms induced by immune responses present critical factors for the success of stem cell therapy. While P1 receptors generally exert beneficial effects including anti-inflammatory activity, P2 receptor-mediated actions depend on the subtype of stimulated receptors and localization of tissue repair. Pro-inflammatory actions and excitatory tissue damages mainly result from P2X7 receptor activation, while other purinergic receptor subtypes participate in proliferation and differentiation, thereby providing adequate niches for stem cell engraftment and novel mechanisms for cell therapy and endogenous tissue repair. Therapeutic applications based on regulation of purinergic signaling are foreseen for kidney and heart muscle regeneration, Clara-like cell replacement for pulmonary and bronchial epithelial cells as well as for induction of neurogenesis in case of neurodegenerative diseases.

Steric Interference of Adhesion Supports In-Vitro Chondrogenesis of Mesenchymal Stem Cells on Hydrogels for Cartilage Repair.

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Goldshmid, Revital; Cohen, Shlomit; Shachaf, Yonatan; Kupershmit, Ilana; Sarig-Nadir, Offra; Seliktar, Dror; Wechsler, Roni

2015-09-28

Recent studies suggest the presence of cell adhesion motifs found in structural proteins can inhibit chondrogenesis. In this context, the current study aims to determine if a polyethylene glycol (PEG)-modified fibrinogen matrix could support better chondrogenesis of human bone marrow mesenchymal stem cells (BM-MSC) based on steric interference of adhesion, when compared to a natural fibrin matrix. Hydrogels used as substrates for two-dimensional (2D) BM-MSC cultures under chondrogenic conditions were made from cross-linked PEG-fibrinogen (PF) and compared to thrombin-activated fibrin. Cell morphology, protein expression, DNA and sulfated proteoglycan (GAG) content were correlated to substrate properties such as stiffness and adhesiveness. Cell aggregation and chondrogenic markers, including collagen II and aggrecan, were observed on all PF substrates but not on fibrin. Shielding fibrinogen's adhesion domains and increasing stiffness of the material are likely contributing factors that cause the BM-MSCs to display a more chondrogenic phenotype. One composition of PF corresponding to GelrinC™--a product cleared in the EU for cartilage repair--was found to be optimal for supporting chondrogenic differentiation of BM-MSC while minimizing hypertrophy (collagen X). These findings suggest that semi-synthetic biomaterials based on ECM proteins can be designed to favourably affect BM-MSC towards repair processes involving chondrogenesis.

Engineering endostatin-producing cartilaginous constructs for cartilage repair using nonviral transfection of chondrocyte-seeded and mesenchymal-stem-cell-seeded collagen scaffolds.

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Jeng, Lily; Olsen, Bjorn R; Spector, Myron

2010-10-01

Although there is widespread recognition of the importance of angiogenesis in tissue repair, there is little work on the inhibition of angiogenesis in the context of tissue engineering of naturally avascular tissues, like articular cartilage. The objective was to engineer a collagen-scaffold-based cartilaginous construct overexpressing a potent antiangiogenic factor, endostatin, using nonviral transfection. Endostatin-plasmid-supplemented collagen scaffolds were seeded with mesenchymal stem cells and chondrocytes and cultured for 20–22 days. The effects of the following variables on endostatin expression and chondrogenesis were examined: collagen scaffold material, method of nonviral vector incorporation, plasmid load, culture medium, and oxygen tension. An increase and peak of endostatin protein was observed during the first week of culture, followed by a decrease to low levels, suggesting that overexpression of endostatin could be sustained for several days using the nonviral vector. The amount of endostatin produced was tunable with the external factors. Chondrogenesis was observed in the engineered constructs cultured in chondrogenic medium at the 3-week time point, demonstrating that endostatin did not inhibit the chondrogenic potential of mesenchymal stem cells or the general viability of the cells. The ability to engineer endostatin-expressing cartilaginous constructs will be of value for future work exercising regulatory control of angiogenesis in cartilage repair.

Parthenogenetic stem cells for tissue-engineered heart repair

NARCIS (Netherlands)

Didie, Michael; Christalla, Peter; Rubart, Michael; Muppala, Vijayakumar; Doeker, Stephan; Unsoeld, Bernhard; El-Armouche, Ali; Rau, Thomas; Eschenhagen, Thomas; Schwoerer, Alexander P.; Ehmke, Heimo; Schumacher, Udo; Fuchs, Sigrid; Lange, Claudia; Becker, Alexander; Tao, Wen; Scherschel, John A.; Soonpaa, Mark H.; Yang, Tao; Lin, Qiong; Zenke, Martin; Han, Dong-Wook; Schoeler, Hans R.; Rudolph, Cornelia; Steinemann, Doris; Schlegelberger, Brigitte; Kattman, Steve; Witty, Alec; Keller, Gordon; Field, Loren J.; Zimmermann, Wolfram-Hubertus

Uniparental parthenotes are considered an unwanted byproduct of in vitro fertilization. In utero parthenote development is severely compromised by defective organogenesis and in particular by defective cardiogenesis. Although developmentally compromised, apparently pluripotent stem cells can be

Human mandible bone defect repair by the grafting of dental pulp stem/progenitor cells and collagen sponge biocomplexes

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R d’Aquino

2009-11-01

Full Text Available In this study we used a biocomplex constructed from dental pulp stem/progenitor cells (DPCs and a collagen sponge scaffold for oro-maxillo-facial (OMF bone tissue repair in patients requiring extraction of their third molars. The experiments were carried out according to our Internal Ethical Committee Guidelines and written informed consent was obtained from the patients. The patients presented with bilateral bone reabsorption of the alveolar ridge distal to the second molar secondary to impaction of the third molar on the cortical alveolar lamina, producing a defect without walls, of at least 1.5 cm in height. This clinical condition does not permit spontaneous bone repair after extraction of the third molar, and eventually leads to loss also of the adjacent second molar. Maxillary third molars were extracted first for DPC isolation and expansion. The cells were then seeded onto a collagen sponge scaffold and the obtained biocomplex was used to fill in the injury site left by extraction of the mandibular third molars. Three months after autologous DPC grafting, alveolar bone of patients had optimal vertical repair and complete restoration of periodontal tissue back to the second molars, as assessed by clinical probing and X-rays. Histological observations clearly demonstrated the complete regeneration of bone at the injury site. Optimal bone regeneration was evident one year after grafting. This clinical study demonstrates that a DPC/collagen sponge biocomplex can completely restore human mandible bone defects and indicates that this cell population could be used for the repair and/or regeneration of tissues and organs.

Transplantation of mesenchymal stem cells cultured on biomatrix support induces repairing of digestive tract defects, in animal model.

Science.gov (United States)

Sîrbu-Boeţi, Mirela-Patricia; Chivu, Mihaela; Pâslaru, Liliana Livia; Efrimescu, C; Herlea, V; Pecheanu, C; Moldovan, Lucia; Dragomir, Laura; Bleotu, Coralia; Ciucur, Elena; Vidulescu, Cristina; Vasilescu, Mihaela; Boicea, Anişoara; Mănoiu, S; Ionescu, M I; Popescu, I

2009-01-01

Transplanted mesenchymal stem cells (MSCs) appear to play a significant role in adult tissue repair. The aim of this research was to obtain MSCs enriched, three dimensional (3D) patches for transplant, and to test their ability to induce repair of iatrogenic digestive tract defects in rats. MSCs were obtained from human and rat bone marrow, cultured in vitro, and seeded in a collagen-agarose scaffold, where they showed enhanced viability and proliferation. The phenotype of the cultured cells was representative for MSCs (CD105+, CD90+, and CD34-, CD45-, CD3-, CD14-). The 3D patch was obtained by laying the MSCs enriched collagen-agarose scaffold on a human or swine aortic fragment. After excision of small portions of the rat digestive tract, the 3D patches were sutured at the edge of the defect using micro-surgical techniques. The rats were sacrificed at time-points and the regeneration of the digestive wall was investigated by immunofluorescence, light and electron microscopy. The MSCs enriched 3D patches were biocompatible, biodegradable, and prompted the regeneration of the four layers of the stomach and intestine wall in rats. Human cells were identified in the rat regenerated digestive wall as a hallmark of the transplanted MSCs. For the first time we constructed 3D patches made of cultured bone marrow MSCs, embedded into a collagen-rich biomatrix, on vascular bio-material support, and transplanted them in order to repair iatrogenic digestive tract defects. The result was a complete repair with preservation of the four layered structure of the digestive wall.

Mesenchymal stem cells (MSCs) as skeletal therapeutics-an update

DEFF Research Database (Denmark)

Saeed, H.; Ahsan, M.; Saleem, Z.

2016-01-01

Mesenchymal stem cells hold the promise to treat not only several congenital and acquired bone degenerative diseases but also to repair and regenerate morbid bone tissues. Utilizing MSCs, several lines of evidences advocate promising clinical outcomes in skeletal diseases and skeletal tissue repair....../regeneration. In this context, both, autologous and allogeneic cell transfer options have been utilized. Studies suggest that MSCs are transplanted either alone by mixing with autogenous plasma/serum or by loading onto repair/induction supportive resorb-able scaffolds. Thus, this review is aimed at highlighting a wide range...

Biodegradable Polymers and Stem Cells for Bioprinting.

Science.gov (United States)

Lei, Meijuan; Wang, Xiaohong

2016-04-29

It is imperative to develop organ manufacturing technologies based on the high organ failure mortality and serious donor shortage problems. As an emerging and promising technology, bioprinting has attracted more and more attention with its super precision, easy reproduction, fast manipulation and advantages in many hot research areas, such as tissue engineering, organ manufacturing, and drug screening. Basically, bioprinting technology consists of inkjet bioprinting, laser-based bioprinting and extrusion-based bioprinting techniques. Biodegradable polymers and stem cells are common printing inks. In the printed constructs, biodegradable polymers are usually used as support scaffolds, while stem cells can be engaged to differentiate into different cell/tissue types. The integration of biodegradable polymers and stem cells with the bioprinting techniques has provided huge opportunities for modern science and technologies, including tissue repair, organ transplantation and energy metabolism.

Crypt base columnar stem cells in small intestines of mice are radioresistant

NARCIS (Netherlands)

Hua, G.; Thin, T.H.; Feldman, R.; Haimovitz-Friedman, A.; Clevers, H.; Fuks, Z.; Kolesnick, R.

2012-01-01

BACKGROUND & AIMS: Adult stem cells have been proposed to be quiescent and radiation resistant, repairing DNA double-strand breaks by nonhomologous end joining. However, the population of putative small intestinal stem cells (ISCs) at position +4 from the crypt base contradicts this model, in that

Combination of edaravone and neural stem cell transplantation repairs injured spinal cord in rats.

Science.gov (United States)

Song, Y Y; Peng, C G; Ye, X B

2015-12-29

This study sought to observe the effect of the combination of edaravone and neural stem cell (NSC) transplantation on the repair of complete spinal cord transection in rats. Eighty adult female Sprague-Dawley (SD) rats were used to establish the injury model of complete spinal cord transection at T9. Animals were divided randomly into four groups (N = 20 each): control, edaravone, transplantation, and edaravone + transplantation. The recovery of spinal function was evaluated with the Basso, Beattie, Bresnahan (BBB) rating scale on days 1, 3, and 7 each week after the surgery. After 8 weeks, the BBB scores of the control, edaravone, transplantation, and combination groups were 4.21 ± 0.11, 8.46 ± 0.1, 8.54 ± 0.13, and 11.21 ± 0.14, respectively. At 8 weeks after surgery, the spinal cord was collected; the survival and transportation of transplanted cells were observed with PKH-26 labeling, and the regeneration and distribution of spinal nerve fibers with fluorescent-gold (FG) retrograde tracing. Five rats died due to the injury. PKH-26-labeled NSCs had migrated into the spinal cord. A few intact nerve fibers and pyramidal neurons passed the injured area in the transplantation and combination groups. The numbers of PKH-26-labeled cells and FG-labeled nerve fibers were in the order: combination group > edaravone group and transplantation group > control group (P edaravone can enhance the survival and differentiation of NSCs in injured areas; edaravone with NSC transplantation can improve the effectiveness of spinal cord injury repair in rats.

Lifespan differences in hematopoietic stem cells are due to imperfect repair and unstable mean-reversion.

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Hans B Sieburg

2013-04-01

Full Text Available The life-long supply of blood cells depends on the long-term function of hematopoietic stem cells (HSCs. HSCs are functionally defined by their multi-potency and self-renewal capacity. Because of their self-renewal capacity, HSCs were thought to have indefinite lifespans. However, there is increasing evidence that genetically identical HSCs differ in lifespan and that the lifespan of a HSC is predetermined and HSC-intrinsic. Lifespan is here defined as the time a HSC gives rise to all mature blood cells. This raises the intriguing question: what controls the lifespan of HSCs within the same animal, exposed to the same environment? We present here a new model based on reliability theory to account for the diversity of lifespans of HSCs. Using clonal repopulation experiments and computational-mathematical modeling, we tested how small-scale, molecular level, failures are dissipated at the HSC population level. We found that the best fit of the experimental data is provided by a model, where the repopulation failure kinetics of each HSC are largely anti-persistent, or mean-reverting, processes. Thus, failure rates repeatedly increase during population-wide division events and are counteracted and decreased by repair processes. In the long-run, a crossover from anti-persistent to persistent behavior occurs. The cross-over is due to a slow increase in the mean failure rate of self-renewal and leads to rapid clonal extinction. This suggests that the repair capacity of HSCs is self-limiting. Furthermore, we show that the lifespan of each HSC depends on the amplitudes and frequencies of fluctuations in the failure rate kinetics. Shorter and longer lived HSCs differ significantly in their pre-programmed ability to dissipate perturbations. A likely interpretation of these findings is that the lifespan of HSCs is determined by preprogrammed differences in repair capacity.

The Evolution of the Stem Cell Theory for Heart Failure.

Science.gov (United States)

Silvestre, Jean-Sébastien; Menasché, Philippe

2015-12-01

Various stem cell-based approaches for cardiac repair have achieved encouraging results in animal experiments, often leading to their rapid proceeding to clinical testing. However, freewheeling evolutionary developments of the stem cell theory might lead to dystopian scenarios where heterogeneous sources of therapeutic cells could promote mixed clinical outcomes in un-stratified patient populations. This review focuses on the lessons that should be learnt from the first generation of stem cell-based strategies and emphasizes the absolute requirement to better understand the basic mechanisms of stem cell biology and cardiogenesis. We will also discuss about the unexpected "big bang" in the stem cell theory, "blasting" the therapeutic cells to their unchallenged ability to release paracrine factors such as extracellular membrane vesicles. Paradoxically, the natural evolution of the stem cell theory for cardiac regeneration may end with the development of cell-free strategies with multiple cellular targets including cardiomyocytes but also other infiltrating or resident cardiac cells.

The Evolution of the Stem Cell Theory for Heart Failure

Directory of Open Access Journals (Sweden)

Jean-Sébastien Silvestre

2015-12-01

Full Text Available Various stem cell-based approaches for cardiac repair have achieved encouraging results in animal experiments, often leading to their rapid proceeding to clinical testing. However, freewheeling evolutionary developments of the stem cell theory might lead to dystopian scenarios where heterogeneous sources of therapeutic cells could promote mixed clinical outcomes in un-stratified patient populations. This review focuses on the lessons that should be learnt from the first generation of stem cell-based strategies and emphasizes the absolute requirement to better understand the basic mechanisms of stem cell biology and cardiogenesis. We will also discuss about the unexpected “big bang” in the stem cell theory, “blasting” the therapeutic cells to their unchallenged ability to release paracrine factors such as extracellular membrane vesicles. Paradoxically, the natural evolution of the stem cell theory for cardiac regeneration may end with the development of cell-free strategies with multiple cellular targets including cardiomyocytes but also other infiltrating or resident cardiac cells.

Epigenetic Memory Underlies Cell-Autonomous Heterogeneous Behavior of Hematopoietic Stem Cells.

Science.gov (United States)

Yu, Vionnie W C; Yusuf, Rushdia Z; Oki, Toshihiko; Wu, Juwell; Saez, Borja; Wang, Xin; Cook, Colleen; Baryawno, Ninib; Ziller, Michael J; Lee, Eunjung; Gu, Hongcang; Meissner, Alexander; Lin, Charles P; Kharchenko, Peter V; Scadden, David T

2016-11-17

Stem cells determine homeostasis and repair of many tissues and are increasingly recognized as functionally heterogeneous. To define the extent of-and molecular basis for-heterogeneity, we overlaid functional, transcriptional, and epigenetic attributes of hematopoietic stem cells (HSCs) at a clonal level using endogenous fluorescent tagging. Endogenous HSC had clone-specific functional attributes over time in vivo. The intra-clonal behaviors were highly stereotypic, conserved under the stress of transplantation, inflammation, and genotoxic injury, and associated with distinctive transcriptional, DNA methylation, and chromatin accessibility patterns. Further, HSC function corresponded to epigenetic configuration but not always to transcriptional state. Therefore, hematopoiesis under homeostatic and stress conditions represents the integrated action of highly heterogeneous clones of HSC with epigenetically scripted behaviors. This high degree of epigenetically driven cell autonomy among HSCs implies that refinement of the concepts of stem cell plasticity and of the stem cell niche is warranted. Copyright © 2016 Elsevier Inc. All rights reserved.

Stem cell homing-based tissue engineering using bioactive materials

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Yu, Yinxian; Sun, Binbin; Yi, Chengqing; Mo, Xiumei

2017-06-01

Tissue engineering focuses on repairing tissue and restoring tissue functions by employing three elements: scaffolds, cells and biochemical signals. In tissue engineering, bioactive material scaffolds have been used to cure tissue and organ defects with stem cell-based therapies being one of the best documented approaches. In the review, different biomaterials which are used in several methods to fabricate tissue engineering scaffolds were explained and show good properties (biocompatibility, biodegradability, and mechanical properties etc.) for cell migration and infiltration. Stem cell homing is a recruitment process for inducing the migration of the systemically transplanted cells, or host cells, to defect sites. The mechanisms and modes of stem cell homing-based tissue engineering can be divided into two types depending on the source of the stem cells: endogenous and exogenous. Exogenous stem cell-based bioactive scaffolds have the challenge of long-term culturing in vitro and for endogenous stem cells the biochemical signal homing recruitment mechanism is not clear yet. Although the stem cell homing-based bioactive scaffolds are attractive candidates for tissue defect therapies, based on in vitro studies and animal tests, there is still a long way before clinical application.

Therapeutic strategies involving uterine stem cells in reproductive medicine.

Science.gov (United States)

Simoni, Michael; Taylor, Hugh S

2018-04-12

The current review provides an update on recent advances in stem cell biology relevant to female reproduction. Stem cells are undifferentiated cells that often serve as a reservoir of cells to regenerate tissue in settings or injury or cell loss. The endometrium has progenitor stem cells that can replace all of the endometrium during each menstrual cycle. In addition, multipotent endometrial cells replace these progenitor cells when depleted. Recruitment of stem cells from outside of the uterus occurs in setting of increased demand such as ischemia or injury. Bone marrow-derived multipotent stem cells are recruited to the uterus by estrogen or injury-induced expression of the chemokine CXCL12. In the setting of overwhelming injury, especially in the setting of low estrogen levels, there may be insufficient stem cell recruitment to adequately repair the uterus resulting in conditions such as Asherman syndrome or other endometrial defects. In contrast, excessive recruitment of stem cells underlies endometriosis. Enhanced understanding of stem-cell mobilization, recruitment, and engraftment has created the possibility of improved therapy for endometrial defects and endometriosis through enhanced manipulation of stem-cell trafficking. Further, the normal endometrium is a rich source of multipotent stem cells that can be used for numerous applications in regenerative medicine beyond reproduction. A better understanding of reproductive stem-cell biology may allow improved treatment of endometrial disease such as Asherman syndrome and other endometrial receptivity defects. Inhibiting stem-cell mobilization may also be helpful in endometriosis therapy. Finally, endometrial derived multipotent stem cells may play a crucial role in cell therapy for regenerative medicine.

Generation of Induced Pluripotent Stem Cells and Neural Stem/Progenitor Cells from Newborns with Spina Bifida Aperta.

Science.gov (United States)

Bamba, Yohei; Nonaka, Masahiro; Sasaki, Natsu; Shofuda, Tomoko; Kanematsu, Daisuke; Suemizu, Hiroshi; Higuchi, Yuichiro; Pooh, Ritsuko K; Kanemura, Yonehiro; Okano, Hideyuki; Yamasaki, Mami

2017-12-01

We established induced pluripotent stem cells (iPSCs) and neural stem/progenitor cells (NSPCs) from three newborns with spina bifida aperta (SBa) using clinically practical methods. We aimed to develop stem cell lines derived from newborns with SBa for future therapeutic use. SBa is a common congenital spinal cord abnormality that causes defects in neurological and urological functions. Stem cell transplantation therapies are predicted to provide beneficial effects for patients with SBa. However, the availability of appropriate cell sources is inadequate for clinical use because of their limited accessibility and expandability, as well as ethical issues. Fibroblast cultures were established from small fragments of skin obtained from newborns with SBa during SBa repair surgery. The cultured cells were transfected with episomal plasmid vectors encoding reprogramming factors necessary for generating iPSCs. These cells were then differentiated into NSPCs by chemical compound treatment, and NSPCs were expanded using neurosphere technology. We successfully generated iPSC lines from the neonatal dermal fibroblasts of three newborns with SBa. We confirmed that these lines exhibited the characteristics of human pluripotent stem cells. We successfully generated NSPCs from all SBa newborn-derived iPSCs with a combination of neural induction and neurosphere technology. We successfully generated iPSCs and iPSC-NSPCs from surgical samples obtained from newborns with SBa with the goal of future clinical use in patients with SBa.

Honey can repairing damage of liver tissue due to protein energy malnutrition through induction of endogenous stem cells

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R. Heru Prasetyo

2017-06-01

Full Text Available Aim: This study was to evaluate effect of honey in repairing damage of liver tissue due to energy protein malnutrition and in mobilization of endogenous stem cells. Materials and Methods: Male mice model of degenerative liver was obtained through food fasting but still have drinking water for 5 days. It caused energy protein malnutrition and damage of liver tissue. The administration of 50% (v/v honey was performed for 10 consecutive days, while the positive control group was fasted and not given honey and the negative control not fasted and without honey. Observations of regeneration the liver tissue based on histologically examination, observation of Hsp70 expression, and homing signal based on vascular endothelial growth factor-1 (VEGF-1 expression using immunohistochemistry technique. Observation on expression of CD34 and CD45 as the marker of auto mobilization of hematopoietic stem cells using flow cytometry technique. Results: There is regeneration of the liver tissue due to protein energy malnutrition, decrease of Hsp70 expression, increase of VEGF-1 expression, and high expression of CD34 and CD45. Conclusion: Honey can improve the liver tissue based on: (1 Mobilization of endogenous stem cells (CD34 and CD45; (2 Hsp70 and VEGF-1 expressions as regeneration marker of improvement, and (3 regeneration histologically of liver tissue.

Chondrogenesis of human adipose derived stem cells for future microtia repair using co-culture technique.

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Goh, Bee See; Che Omar, Siti Nurhadis; Ubaidah, Muhammad Azhan; Saim, Lokman; Sulaiman, Shamsul; Chua, Kien Hui

2017-04-01

In conclusion, these result showed HADSCs could differentiate into chondrocytes-like cells, dependent on signaling induced by TGF-β3 and chondrocytes. This is a promising result and showed that HADSCs is a potential source for future microtia repair. The technique of co-culture is a positive way forward to assist the microtia tissue. Reconstructive surgery for the repair of microtia still remains the greatest challenge among the surgeons. Its repair is associated with donor-site morbidity and the degree of infection is inevitable when using alloplastic prosthesis with uncertain long-term durability. Thus, human adipose derived stem cells (HADSCs) can be an alternative cell source for cartilage regeneration. This study aims to evaluate the chondrogenic potential of HADSCs cultured with transforming growth factor-beta (TGF-β) and interaction of auricular chondrocytes with HADSCs for new cartilage generation. Multi-lineages differentiation features of HADSCs were monitored by Alcian Blue, Alizarin Red, and Oil Red O staining for chondrogenic, adipogenic, and osteogenic differentiation capacity, respectively. Further, HADSCs alone were culture in medium added with TGF-β3; and human auricular chondrocytes were interacted indirectly in the culture with and without TGF-βs for up to 21 days, respectively. Cell morphology and chondrogenesis were monitored by inverted microscope. For cell viability, Alamar Blue assay was used to measure the cell viability and the changes in gene expression of auricular chondrocyte markers were determined by real-time polymerase chain reaction analysis. For the induction of chondrogenic differentiation, HADSCs showed a feature of aggregation and formed a dense matrix of proteoglycans. Staining results from Alizirin Red and Oil Red O indicated the HADSCs also successfully differentiated into adipogenic and osteogenic lineages after 21 days. According to a previous study, HADSCs were strongly positive for the mesenchymal markers CD90, CD73

Biodegradable Polymers and Stem Cells for Bioprinting

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Meijuan Lei

2016-04-01

Full Text Available It is imperative to develop organ manufacturing technologies based on the high organ failure mortality and serious donor shortage problems. As an emerging and promising technology, bioprinting has attracted more and more attention with its super precision, easy reproduction, fast manipulation and advantages in many hot research areas, such as tissue engineering, organ manufacturing, and drug screening. Basically, bioprinting technology consists of inkjet bioprinting, laser-based bioprinting and extrusion-based bioprinting techniques. Biodegradable polymers and stem cells are common printing inks. In the printed constructs, biodegradable polymers are usually used as support scaffolds, while stem cells can be engaged to differentiate into different cell/tissue types. The integration of biodegradable polymers and stem cells with the bioprinting techniques has provided huge opportunities for modern science and technologies, including tissue repair, organ transplantation and energy metabolism.

Layer-by-Layer Bioprinting of Stem Cells for Retinal Tissue Regeneration

Science.gov (United States)

2016-12-01

Precision Tissue Models”, Distinguished Seminar, Eli and Edythe Broad CIRM Center for Regenerative Medicine and Stem Cell Research, University of...in vitro drug screening and potential in vivo retinal neuron repair. The expansion of ganglion cells is tightly related to the spatial arrangement of...AWARD NUMBER: W81XWH-14-1-0522 TITLE: Layer-by-Layer Bioprinting of Stem Cells for Retinal Tissue Regeneration PRINCIPAL INVESTIGATOR

Cell surface glycan engineering of neural stem cells augments neurotropism and improves recovery in a murine model of multiple sclerosis

KAUST Repository

Merzaban, Jasmeen S.

2015-09-13

Neural stem cell (NSC)-based therapies offer potential for neural repair in central nervous system (CNS) inflammatory and degenerative disorders. Typically, these conditions present with multifocal CNS lesions making it impractical to inject NSCs locally, thus mandating optimization of vascular delivery of the cells to involved sites. Here, we analyzed NSCs for expression of molecular effectors of cell migration and found that these cells are natively devoid of E-selectin ligands. Using glycosyltransferase-programmed stereosubstitution (GPS), we glycan engineered the cell surface of NSCs ("GPS-NSCs") with resultant enforced expression of the potent E-selectin ligand HCELL (hematopoietic cell E-/L-selectin ligand) and of an E-selectin-binding glycoform of neural cell adhesion molecule ("NCAM-E"). Following intravenous (i.v.) injection, short-term homing studies demonstrated that, compared with buffer-treated (control) NSCs, GPS-NSCs showed greater neurotropism. Administration of GPS-NSC significantly attenuated the clinical course of experimental autoimmune encephalomyelitis (EAE), with markedly decreased inflammation and improved oligodendroglial and axonal integrity, but without evidence of long-term stem cell engraftment. Notably, this effect of NSC is not a universal property of adult stem cells, as administration of GPS-engineered mouse hematopoietic stem/progenitor cells did not improve EAE clinical course. These findings highlight the utility of cell surface glycan engineering to boost stem cell delivery in neuroinflammatory conditions and indicate that, despite the use of a neural tissue-specific progenitor cell population, neural repair in EAE results from endogenous repair and not from direct, NSC-derived cell replacement.

Facts about Stem Cells and Importance of Them

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Masumeh Saeidi

2014-05-01

Full Text Available Stem cells are undifferentiated biological cells that can differentiate into specialized cells and can divide (through mitosis to produce more stem cells. They are found in multicellular organisms. In mammals, there are two broad types of stem cells: embryonic stem cells, which are isolated from the inner cell mass of blastocysts, and adult stem cells, which are found in various tissues. In adult organisms, stem cells and progenitor cells act as a repair system for the body, replenishing adult tissues. In a developing embryo, stem cells can differentiate into all the specialized cells—ectoderm, endoderm and mesoderm (see induced pluripotent stem cells—but also maintain the normal turnover of regenerative organs, such as blood, skin, or intestinal tissues. There are three accessible sources of autologous adult stem cells in humans: Bone marrow, which requires extraction by harvesting, that is, drilling into bone (typically the femur or iliac crest, Adipose tissue (lipid cells, which requires extraction by liposuction, and Blood, which requires extraction through apheresis, wherein blood is drawn from the donor (similar to a blood donation, and passed through a machine that extracts the stem cells and returns other portions of the blood to the donor. Stem cells can also be taken from umbilical cord blood just after birth. Of all stem cell types, autologous harvesting involves the least risk. By definition, autologous cells are obtained from one's own body, just as one may bank his or her own blood for elective surgical procedures. Adult stem cells are frequently used in medical therapies, for example in bone marrow transplantation. Stem cells can now be artificially grown and transformed (differentiated into specialized cell types with characteristics consistent with cells of various tissues such as muscles or nerves. Embryonic cell lines and autologous embryonic stem cells generated through Somatic-cell nuclear transfer or dedifferentiation

Mesenchymal stem cells in cartilage regeneration.

Science.gov (United States)

Savkovic, Vuk; Li, Hanluo; Seon, Jong-Keun; Hacker, Michael; Franz, Sandra; Simon, Jan-Christoph

2014-01-01

Articular cartilage provides life-long weight-bearing and mechanical lubrication with extraordinary biomechanical performance and simple structure. However, articular cartilage is apparently vulnerable to multifactorial damage and insufficient to self-repair, isolated in articular capsule without nerves or blood vessels. Osteoarthritis (OA) is known as a degenerative articular cartilage deficiency progressively affecting large proportion of the world population, and restoration of hyaline cartilage is clinical challenge to repair articular cartilage lesion and recreate normal functionality over long period. Mesenchymal stem cells (MSC) are highly proliferative and multipotent somatic cells that are able to differentiate mesoderm-derived cells including chondrocytes and osteoblasts. Continuous endeavors in basic research and preclinical trial have achieved promising outcomes in cartilage regeneration using MSCs. This review focuses on rationale and technologies of MSC-based hyaline cartilage repair involving tissue engineering, 3D biomaterials and growth factors. By comparing conventional treatment and current research progress, we describe insights of advantage and challenge in translation and application of MSC-based chondrogenesis for OA treatment.

Transplantation of an LGR6+ Epithelial Stem Cell-Enriched Scaffold for Repair of Full-Thickness Soft-Tissue Defects: The In Vitro Development of Polarized Hair-Bearing Skin.

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Lough, Denver M; Wetter, Nathan; Madsen, Christopher; Reichensperger, Joel; Cosenza, Nicole; Cox, Lisa; Harrison, Carrie; Neumeister, Michael W

2016-02-01

Recent literature has shown that full-thickness wounds, devoid of the stem cell niche, can subsequently be reconstructed with functional skin elements following migration of the LGR6 epithelial stem cell into the wound bed. In this study, the authors use a variety of LGR6 epithelial stem cell-seeded scaffolds to determine therapeutic utility and regenerative potential in the immediate reconstruction of full-thickness wounds. Isolated LGR6 epithelial stem cells were seeded onto a spectrum of acellular matrices and monitored in both in vitro and in vivo settings to determine their relative capacity to regenerate tissues and heal wounds. Wound beds containing LGR6 stem cell-seeded scaffolds showed significantly augmented rates of healing, epithelialization, and hair growth compared with controls. Gene and proteomic expression studies indicate that LGR6 stem cell-seeded constructs up-regulate WNT, epidermal growth factor, and angiogenesis pathways. Finally, the addition of stromal vascular fraction to LGR6 stem cell-seeded constructs induces polarized tissue formation, nascent hair growth, and angiogenesis within wounds. LGR6 stem cells are able to undergo proliferation, differentiation, and migration following seeding onto a variety of collagen-based scaffolding. In addition, deployment of these constructs induces epithelialization, hair growth, and angiogenesis within wound beds. The addition of stromal vascular fraction to LGR6 stem cell-containing scaffolds initiated an early form of tissue polarization, providing for the first time a clinically applicable stem cell-based construct that is capable of the repair of full-thickness wounds and hair regeneration. Therapeutic, V.

Electroacupuncture in the repair of spinal cord injury: inhibiting the Notch signaling pathway and promoting neural stem cell proliferation

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Xin Geng

2015-01-01

Full Text Available Electroacupuncture for the treatment of spinal cord injury has a good clinical curative effect, but the underlying mechanism is unclear. In our experiments, the spinal cord of adult Sprague-Dawley rats was clamped for 60 seconds. Dazhui (GV14 and Mingmen (GV4 acupoints of rats were subjected to electroacupuncture. Enzyme-linked immunosorbent assay revealed that the expression of serum inflammatory factors was apparently downregulated in rat models of spinal cord injury after electroacupuncture. Hematoxylin-eosin staining and immunohistochemistry results demonstrated that electroacupuncture contributed to the proliferation of neural stem cells in rat injured spinal cord, and suppressed their differentiation into astrocytes. Real-time quantitative PCR and western blot assays showed that electroacupuncture inhibited activation of the Notch signaling pathway induced by spinal cord injury. These findings indicate that electroacupuncture repaired the injured spinal cord by suppressing the Notch signaling pathway and promoting the proliferation of endogenous neural stem cells.

Chemically Induced Reprogramming of Somatic Cells to Pluripotent Stem Cells and Neural Cells.

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Biswas, Dhruba; Jiang, Peng

2016-02-06

The ability to generate transplantable neural cells in a large quantity in the laboratory is a critical step in the field of developing stem cell regenerative medicine for neural repair. During the last few years, groundbreaking studies have shown that cell fate of adult somatic cells can be reprogrammed through lineage specific expression of transcription factors (TFs)-and defined culture conditions. This key concept has been used to identify a number of potent small molecules that could enhance the efficiency of reprogramming with TFs. Recently, a growing number of studies have shown that small molecules targeting specific epigenetic and signaling pathways can replace all of the reprogramming TFs. Here, we provide a detailed review of the studies reporting the generation of chemically induced pluripotent stem cells (ciPSCs), neural stem cells (ciNSCs), and neurons (ciN). We also discuss the main mechanisms of actions and the pathways that the small molecules regulate during chemical reprogramming.

Regeneration of articular cartilage by adipose tissue derived mesenchymal stem cells: perspectives from stem cell biology and molecular medicine.

Science.gov (United States)

Wu, Ling; Cai, Xiaoxiao; Zhang, Shu; Karperien, Marcel; Lin, Yunfeng

2013-05-01

Adipose-derived stem cells (ASCs) have been discovered for more than a decade. Due to the large numbers of cells that can be harvested with relatively little donor morbidity, they are considered to be an attractive alternative to bone marrow derived mesenchymal stem cells. Consequently, isolation and differentiation of ASCs draw great attention in the research of tissue engineering and regenerative medicine. Cartilage defects cause big therapeutic problems because of their low self-repair capacity. Application of ASCs in cartilage regeneration gives hope to treat cartilage defects with autologous stem cells. In recent years, a lot of studies have been performed to test the possibility of using ASCs to re-construct damaged cartilage tissue. In this article, we have reviewed the most up-to-date articles utilizing ASCs for cartilage regeneration in basic and translational research. Our topic covers differentiation of adipose tissue derived mesenchymal stem cells into chondrocytes, increased cartilage formation by co-culture of ASCs with chondrocytes and enhancing chondrogenic differentiation of ASCs by gene manipulation. Copyright © 2012 Wiley Periodicals, Inc.

Mesenchymal stem cells in human placental chorionic villi reside in a vascular Niche

NARCIS (Netherlands)

Castrechini, N. M.; Murthi, P.; Gude, N. M.; Erwich, J. J. H. M.; Gronthos, S.; Zannettino, A.; Brennecke, S. R.; Kalionis, B.; Brennecke, S.P.

The chorionic villi of human term placentae are a rich source of mesenchymal stem cells (PMSCs) The stem cell "niche" within the chorionic villi regulates how PMSCs participate in placental tissue generation, maintenance and repair, but the anatomic location of the niche has not been defined A

Effectiveness of Wharton's jelly stem cells in gastroschisis repair ...

African Journals Online (AJOL)

The inner surface of the umbilical patch is a 'live' structure with WJ, which contains mucoid connective tissue and fibroblast-like cells – that is, stem cells producing cutis, adipose, and connective tissue. Results Using our method, early control assessment of 18 of 21 patients with gastroschisis, at intervals of 1–3 months, ...

Pituitary cell differentiation from stem cells and other cells: toward restorative therapy for hypopituitarism?

Science.gov (United States)

Willems, Christophe; Vankelecom, Hugo

2014-01-01

The pituitary gland, key regulator of our endocrine system, produces multiple hormones that steer essential physiological processes. Hence, deficient pituitary function (hypopituitarism) leads to severe disorders. Hypopituitarism can be caused by defective embryonic development, or by damage through tumor growth/resection and traumatic brain injury. Lifelong hormone replacement is needed but associated with significant side effects. It would be more desirable to restore pituitary tissue and function. Recently, we showed that the adult (mouse) pituitary holds regenerative capacity in which local stem cells are involved. Repair of deficient pituitary may therefore be achieved by activating these resident stem cells. Alternatively, pituitary dysfunction may be mended by cell (replacement) therapy. The hormonal cells to be transplanted could be obtained by (trans-)differentiating various kinds of stem cells or other cells. Here, we summarize the studies on pituitary cell regeneration and on (trans-)differentiation toward hormonal cells, and speculate on restorative therapies for pituitary deficiency.

[Research progress of intervertebral disc endogenous stem cells for intervertebral disc regeneration].

Science.gov (United States)

Liang, Hang; Deng, Xiangyu; Shao, Zengwu

2017-10-01

To summarize the research progress of intervertebral disc endogenous stem cells for intervertebral disc regeneration and deduce the therapeutic potential of endogenous repair for intervertebral disc degeneration. The original articles about intervertebral disc endogenous stem cells for intervertebral disc regeneration were extensively reviewed; the reparative potential in vivo and the extraction and identification in vitro of intervertebral disc endogenous stem cells were analyzed; the prospect of endogenous stem cells for intervertebral disc regeneration was predicted. Stem cell niche present in the intervertebral discs, from which stem cells migrate to injured tissues and contribute to tissues regeneration under certain specific microenvironment. Moreover, the migration of stem cells is regulated by chemokines system. Tissue specific progenitor cells have been identified and successfully extracted and isolated. The findings provide the basis for biological therapy of intervertebral disc endogenous stem cells. Intervertebral disc endogenous stem cells play a crucial role in intervertebral disc regeneration. Therapeutic strategy of intervertebral disc endogenous stem cells is proven to be a promising biological approach for intervertebral disc regeneration.

Use of the second harmonic generation microscopy to evaluate chondrogenic differentiation of mesenchymal stem cells for cartilage repair

Science.gov (United States)

Bordeaux-Rego, P.; Baratti, M. O.; Duarte, A. S. S.; Ribeiro, T. B.; Andreoli-Risso, M. F.; Vidal, B.; Miranda, J. B.; Adur, J.; de Thomaz, A. A.; Pelegati, V. B.; Costa, F. F.; Carvalho, H. F.; Cesar, C. L.; Luzo, A.; Olalla Saad, S. T.

2012-03-01

Articular cartilage injury remains one of the major concerns in orthopedic surgery. Mesenchymal stem cell (MSC) transplantation has been introduced to avoid some of the side effects and complications of current techniques.. With the aim to evaluate chondrogenic differentiation of mesenchymal stem cells, we used Second Harmonic Generation (SHG) microscopy to analyze the aggregation and orientation of collagen fibrils in the hyaline cartilage of rabbit knees. The experiment was performed using implants with type II collagen hydrogel (a biomaterial that mimics the microenvironment of the cartilage), one implant containing MSC and one other without MSC (control). After 10 weeks, the rabbit knees were dissected and fibril collagen distribution and spatial organization in the extracellular matrix of the lesions were verified by SHG. The result showed significant differences, whereas in histological sections of the cartilaginous lesions with MSC the collagen fibers are organized and regular; in the control sections the collagen fibers are more irregular, with absence of cells. A macroscopic analysis of the lesions confirmed this difference, showing a greater percentage of lesions filling in knees treated with MSC than in the knees used as controls. This study demonstrates that SHG microscopy will be an excellent tool to help in the evaluation of the effectiveness of MSC-based cell therapy for cartilage repair.

Isolation, characterization, and differentiation of stem cells for cartilage regeneration.

Science.gov (United States)

Beane, Olivia S; Darling, Eric M

2012-10-01

The goal of tissue engineering is to create a functional replacement for tissues damaged by injury or disease. In many cases, impaired tissues cannot provide viable cells, leading to the investigation of stem cells as a possible alternative. Cartilage, in particular, may benefit from the use of stem cells since the tissue has low cellularity and cannot effectively repair itself. To address this need, researchers are investigating the chondrogenic capabilities of several multipotent stem cell sources, including adult and extra-embryonic mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), and induced pluripotent stem cells (iPSCs). Comparative studies indicate that each cell type has advantages and disadvantages, and while direct comparisons are difficult to make, published data suggest some sources may be more promising for cartilage regeneration than others. In this review, we identify current approaches for isolating and chondrogenically differentiating MSCs from bone marrow, fat, synovium, muscle, and peripheral blood, as well as cells from extra-embryonic tissues, ESCs, and iPSCs. Additionally, we assess chondrogenic induction with growth factors, identifying standard cocktails used for each stem cell type. Cell-only (pellet) and scaffold-based studies are also included, as is a discussion of in vivo results.

Platelet-Rich Plasma Derived Growth Factors Contribute to Stem Cell Differentiation in Musculoskeletal Regeneration

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Yun Qian

2017-10-01

Full Text Available Stem cell treatment and platelet-rich plasma (PRP therapy are two significant issues in regenerative medicine. Stem cells such as bone marrow mesenchymal stem cells, adipose-derived stem cells and periodontal ligament stem cells can be successfully applied in the field of tissue regeneration. PRP, a natural product isolated from whole blood, can secrete multiple growth factors (GFs for regulating physiological activities. These GFs can stimulate proliferation and differentiation of different stem cells in injury models. Therefore, combination of both agents receives wide expectations in regenerative medicine, especially in bone, cartilage and tendon repair. In this review, we thoroughly discussed the interaction and underlying mechanisms of PRP derived GFs with stem cells, and assessed their functions in cell differentiation for musculoskeletal regeneration.

Platelet-rich plasma derived growth factors contribute to stem cell differentiation in musculoskeletal regeneration

Science.gov (United States)

Qian, Yun; Han, Qixin; Chen, Wei; Song, Jialin; Zhao, Xiaotian; Ouyang, Yuanming; Yuan, Weien; Fan, Cunyi

2017-10-01

Stem cell treatment and platelet-rich plasma (PRP) therapy are two significant issues in regenerative medicine. Stem cells such as bone marrow mesenchymal stem cells, adipose-derived stem cells and periodontal ligament stem cells can be successfully applied in the field of tissue regeneration. PRP, a natural product isolated from whole blood, can secrete multiple growth factors (GFs) for regulating physiological activities. These GFs can stimulate proliferation and differentiation of different stem cells in injury models. Therefore, combination of both agents receives wide expectations in regenerative medicine, especially in bone, cartilage and tendon repair. In this review, we thoroughly discussed the interaction and underlying mechanisms of platelet-rich plasma derived growth factors with stem cells, and assessed their functions in cell differentiation for musculoskeletal regeneration.

Paracrine Maturation and Migration of SH-SY5Y Cells by Dental Pulp Stem Cells

OpenAIRE

Gervois, Pascal; Wolfs, Esther; Dillen, Yörg; Hilkens, Petra; Ratajczak, Jessica; Driesen, Ronald; Vangansewinkel, Tim; Bronckaers, Annelies; Brône, Bert; Struys, Tom; Lambrichts, Ivo

2017-01-01

Neurological disorders are characterized by neurodegeneration and/or loss of neuronal function, which cannot be adequately repaired by the host. Therefore, there is need for novel treatment options such as cell-based therapies that aim to salvage or reconstitute the lost tissue or that stimulate host repair. The present study aimed to evaluate the paracrine effects of human dental pulp stem cells (hDPSCs) on the migration and neural maturation of human SH-SY5Y neuroblastoma cells. The hDPSC s...

Engineered stem cell niche matrices for rotator cuff tendon regenerative engineering.

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M Sean Peach

Full Text Available Rotator cuff (RC tears represent a large proportion of musculoskeletal injuries attended to at the clinic and thereby make RC repair surgeries one of the most widely performed musculoskeletal procedures. Despite the high incidence rate of RC tears, operative treatments have provided minimal functional gains and suffer from high re-tear rates. The hypocellular nature of tendon tissue poses a limited capacity for regeneration. In recent years, great strides have been made in the area of tendonogenesis and differentiation towards tendon cells due to a greater understanding of the tendon stem cell niche, development of advanced materials, improved scaffold fabrication techniques, and delineation of the phenotype development process. Though in vitro models for tendonogenesis have shown promising results, in vivo models have been less successful. The present work investigates structured matrices mimicking the tendon microenvironment as cell delivery vehicles in a rat RC tear model. RC injuries augmented with a matrix delivering rat mesenchymal stem cells (rMSCs showed enhanced regeneration over suture repair alone or repair with augmentation, at 6 and 12-weeks post-surgery. The local delivery of rMSCs led to increased mechanical properties and improved tissue morphology. We hypothesize that the mesenchymal stem cells function to modulate the local immune and bioactivity environment through autocrine/paracrine and/or cell homing mechanisms. This study provides evidence for improved tendon healing with biomimetic matrices and delivered MSCs with the potential for translation to larger, clinical animal models. The enhanced regenerative healing response with stem cell delivering biomimetic matrices may represent a new treatment paradigm for massive RC tendon tears.

Explanation for excessive DNA single-strand breaks and endogenous repair foci in pluripotent mouse embryonic stem cells.

Science.gov (United States)

Banáth, J P; Bañuelos, C A; Klokov, D; MacPhail, S M; Lansdorp, P M; Olive, P L

2009-05-01

Pluripotent mouse embryonic stem cells (mES cells) exhibit approximately 100 large gammaH2AX repair foci in the absence of measurable numbers of DNA double-strand breaks. Many of these cells also show excessive numbers of DNA single-strand breaks (>10,000 per cell) when analyzed using the alkaline comet assay. To understand the reasons for these unexpected observations, various methods for detecting DNA strand breaks were applied to wild-type mES cells and to mES cells lacking H2AX, ATM, or DNA-PKcs. H2AX phosphorylation and expression of other repair complexes were measured using flow and image analysis of antibody-stained cells. Results indicate that high numbers of endogenous gammaH2AX foci and single-strand breaks in pluripotent mES cells do not require ATM or DNA-PK kinase activity and appear to be associated with global chromatin decondensation rather than pre-existing DNA damage. This will limit applications of gammaH2AX foci analysis in mES cells to relatively high levels of initial or residual DNA damage. Excessive numbers of single-strand breaks in the alkaline comet assay can be explained by the vulnerability of replicating chromatin in mES cells to osmotic shock. This suggests that caution is needed in interpreting results with the alkaline comet assay when applied to certain cell types or after treatment with agents that make chromatin vulnerable to osmotic changes. Differentiation of mES cells caused a reduction in histone acetylation, gammaH2AX foci intensity, and DNA single-strand breakage, providing a link between chromatin structural organization, excessive gammaH2AX foci, and sensitivity of replicating mES cell chromatin to osmotic shock.

Insight on stem cell preconditioning and instructive biomaterials to enhance cell adhesion, retention, and engraftment for tissue repair.

Science.gov (United States)

Shafiq, Muhammad; Jung, Youngmee; Kim, Soo Hyun

2016-06-01

Stem cells are a promising solution for the treatment of a variety of diseases. However, the limited survival and engraftment of transplanted cells due to a hostile ischemic environment is a bottleneck for effective utilization and commercialization. Within this environment, the majority of transplanted cells undergo apoptosis prior to participating in lineage differentiation and cellular integration. Therefore, in order to maximize the clinical utility of stem/progenitor cells, strategies must be employed to increase their adhesion, retention, and engraftment in vivo. Here, we reviewed key strategies that are being adopted to enhance the survival, retention, and engraftment of transplanted stem cells through the manipulation of both the stem cells and the surrounding environment. We describe how preconditioning of cells or cell manipulations strategies can enhance stem cell survival and engraftment after transplantation. We also discuss how biomaterials can enhance the function of stem cells for effective tissue regeneration. Biomaterials can incorporate or mimic extracellular function (ECM) function and enhance survival or differentiation of transplanted cells in vivo. Biomaterials can also promote angiogenesis, enhance engraftment and differentiation, and accelerate electromechanical integration of transplanted stem cells. Insight gained from this review may direct the development of future investigations and clinical trials. Copyright © 2016 Elsevier Ltd. All rights reserved.

Persistent Inflammation Alters the Function of the Endogenous Brain Stem Cell Compartment

OpenAIRE

Pluchino, Stefano; Muzio, Luca; Alfaro-Cervello, Clara; Salani, Giuliana; Porcheri, Cristina; Brambilla, Elena; Cavasinni, Francesca; Bergamaschi, Andrea; Garcia-Verdugo, Jose Manuel; Comi, Giancarlo; Martino, Gianvito; Imitola, Jaime; Deleidi, Michela; Khoury, Samia Joseph

2008-01-01

Endogenous neural stem/precursor cells (NPCs) are considered a functional reservoir for promoting tissue homeostasis and repair after injury, therefore regenerative strategies that mobilize these cells have recently been proposed. Despite evidence of increased neurogenesis upon acute inflammatory insults (e.g. ischaemic stroke), the plasticity of the endogenous brain stem cell compartment in chronic CNS inflammatory disorders remains poorly characterized. Here we show that persistent brain in...

Prospect of Induced Pluripotent Stem Cell Genetic Repair to Cure Genetic Diseases

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Jeanne Adiwinata Pawitan

2012-01-01

Full Text Available In genetic diseases, where the cells are already damaged, the damaged cells can be replaced by new normal cells, which can be differentiated from iPSC. To avoid immune rejection, iPSC from the patient’s own cell can be developed. However, iPSC from the patients’s cell harbors the same genetic aberration. Therefore, before differentiating the iPSCs into required cells, genetic repair should be done. This review discusses the various technologies to repair the genetic aberration in patient-derived iPSC, or to prevent the genetic aberration to cause further damage in the iPSC-derived cells, such as Zn finger and TALE nuclease genetic editing, RNA interference technology, exon skipping, and gene transfer method. In addition, the challenges in using the iPSC and the strategies to manage the hurdles are addressed.

Adult neural stem cells: The promise of the future

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Philippe Taupin

2007-01-01

Full Text Available Philippe TaupinNational Neuroscience Institute, National University of SingaporeAbstract: Stem cells are self-renewing undifferentiated cells that give rise to multiple types of specialized cells of the body. In the adult, stem cells are multipotents and contribute to homeostasis of the tissues and regeneration after injury. Until recently, it was believed that the adult brain was devoid of stem cells, hence unable to make new neurons and regenerate. With the recent evidences that neurogenesis occurs in the adult brain and neural stem cells (NSCs reside in the adult central nervous system (CNS, the adult brain has the potential to regenerate and may be amenable to repair. The function(s of NSCs in the adult CNS remains the source of intense research and debates. The promise of the future of adult NSCs is to redefine the functioning and physiopathology of the CNS, as well as to treat a broad range of CNS diseases and injuries.Keywords: neurogenesis, transdifferentiation, plasticity, cellular therapy

Osteocalcin expressing cells from tendon sheaths in mice contribute to tendon repair by activating Hedgehog signaling

OpenAIRE

Wang, Yi; Zhang, Xu; Huang, Huihui; Xia, Yin; Yao, YiFei; Mak, Arthur Fuk-Tat; Yung, Patrick Shu-Hang; Chan, Kai-Ming; Wang, Li; Zhang, Chenglin; Huang, Yu; Mak, Kingston King-Lun

2017-01-01

Both extrinsic and intrinsic tissues contribute to tendon repair, but the origin and molecular functions of extrinsic tissues in tendon repair are not fully understood. Here we show that tendon sheath cells harbor stem/progenitor cell properties and contribute to tendon repair by activating Hedgehog signaling. We found that Osteocalcin (Bglap) can be used as an adult tendon-sheath-specific marker in mice. Lineage tracing experiments show that Bglap-expressing cells in adult sheath tissues pos...

Analysing the bioactive makeup of demineralised dentine matrix on bone marrow mesenchymal stem cells for enhanced bone repair.

Science.gov (United States)

Avery, S J; Sadaghiani, L; Sloan, A J; Waddington, R J

2017-07-10

Dentine matrix has proposed roles for directing mineralised tissue repair in dentine and bone; however, the range of bioactive components in dentine and specific biological effects on bone-derived mesenchymal stem cells (MSCs) in humans are less well understood. The aims of this study were to further elucidate the biological response of MSCs to demineralised dentine matrix (DDM) in enhancing wound repair responses and ascertain key contributing components. Dentine was obtained from human teeth and DDM proteins solubilised with ethylenediaminetetraacetic acid (EDTA). Bone marrow derived MSCs were commercially obtained. Cells with a more immature phenotype were then selected by preferential fibronectin adhesion (FN-BMMSCs) for use in subsequent in vitro assays. DDM at 10 µg/mL reduced cell expansion, attenuated apoptosis and was the minimal concentration capable of inducing osteoblastic differentiation. Enzyme-linked immunosorbent assay (ELISA) quantification of growth factors indicated physiological levels produced the above responses; transforming growth factor β (TGF-β1) was predominant (15.6 ng/mg DDM), with relatively lower concentrations of BMP-2, FGF, VEGF and PDGF (6.2-4.7 ng/mg DDM). Fractionation of growth factors from other DDM components by heparin affinity chromatography diminished osteogenic responses. Depletion of biglycan from DDM also attenuated osteogenic potency, which was partially rescued by the isolated biglycan. Decorin depletion from DDM had no influence on osteogenic potency. Collectively, these results demonstrate the potential of DDM for the delivery of physiological levels of growth factors for bone repair processes, and substantiate a role for biglycan as an additional adjuvant for driving osteogenic pathways.

Hematopoietic Stem Cells from Ts65Dn Mice Are Deficient in the Repair of DNA Double-Strand Breaks.

Science.gov (United States)

Wang, Yingying; Chang, Jianhui; Shao, Lijian; Feng, Wei; Luo, Yi; Chow, Marie; Du, Wei; Meng, Aimin; Zhou, Daohong

2016-06-01

Down syndrome (DS) is a genetic disorder caused by the presence of an extra partial or whole copy of chromosome 21. In addition to musculoskeletal and neurodevelopmental abnormalities, children with DS exhibit various hematologic disorders and have an increased risk of developing acute lymphoblastic leukemia and acute megakaryocytic leukemia. Using the Ts65Dn mouse model, we investigated bone marrow defects caused by trisomy for 132 orthologs of the genes on human chromosome 21. The results showed that, although the total bone marrow cellularity as well as the frequency of hematopoietic progenitor cells (HPCs) was comparable between Ts65Dn mice and their age-matched euploid wild-type (WT) control littermates, human chromosome 21 trisomy led to a significant reduction in hematopoietic stem cell (HSC) numbers and clonogenic function in Ts65Dn mice. We also found that spontaneous DNA double-strand breaks (DSBs) were significantly increased in HSCs from the Ts65Dn mice, which was correlated with the significant reduction in HSC clonogenic activity compared to those from WT controls. Moreover, analysis of the repair kinetics of radiation-induced DSBs revealed that HSCs from Ts65Dn mice were less proficient in DSB repair than the cells from WT controls. This deficiency was associated with a higher sensitivity of Ts65Dn HSCs to radiation-induced suppression of HSC clonogenic activity than that of euploid HSCs. These findings suggest that an additional copy of genes on human chromosome 21 may selectively impair the ability of HSCs to repair DSBs, which may contribute to DS-associated hematological abnormalities and malignancies.

Effect of Human Adipose Tissue Mesenchymal Stem Cells on the Regeneration of Ovine Articular Cartilage.

Science.gov (United States)

Zorzi, Alessandro R; Amstalden, Eliane M I; Plepis, Ana Maria G; Martins, Virginia C A; Ferretti, Mario; Antonioli, Eliane; Duarte, Adriana S S; Luzo, Angela C M; Miranda, João B

2015-11-09

Cell therapy is a promising approach to improve cartilage healing. Adipose tissue is an abundant and readily accessible cell source. Previous studies have demonstrated good cartilage repair results with adipose tissue mesenchymal stem cells in small animal experiments. This study aimed to examine these cells in a large animal model. Thirty knees of adult sheep were randomly allocated to three treatment groups: CELLS (scaffold seeded with human adipose tissue mesenchymal stem cells), SCAFFOLD (scaffold without cells), or EMPTY (untreated lesions). A partial thickness defect was created in the medial femoral condyle. After six months, the knees were examined according to an adaptation of the International Cartilage Repair Society (ICRS 1) score, in addition to a new Partial Thickness Model scale and the ICRS macroscopic score. All of the animals completed the follow-up period. The CELLS group presented with the highest ICRS 1 score (8.3 ± 3.1), followed by the SCAFFOLD group (5.6 ± 2.2) and the EMPTY group (5.2 ± 2.4) (p = 0.033). Other scores were not significantly different. These results suggest that human adipose tissue mesenchymal stem cells promoted satisfactory cartilage repair in the ovine model.

Strategies to Optimize Adult Stem Cell Therapy for Tissue Regeneration

Directory of Open Access Journals (Sweden)

Shan Liu

2016-06-01

Full Text Available Stem cell therapy aims to replace damaged or aged cells with healthy functioning cells in congenital defects, tissue injuries, autoimmune disorders, and neurogenic degenerative diseases. Among various types of stem cells, adult stem cells (i.e., tissue-specific stem cells commit to becoming the functional cells from their tissue of origin. These cells are the most commonly used in cell-based therapy since they do not confer risk of teratomas, do not require fetal stem cell maneuvers and thus are free of ethical concerns, and they confer low immunogenicity (even if allogenous. The goal of this review is to summarize the current state of the art and advances in using stem cell therapy for tissue repair in solid organs. Here we address key factors in cell preparation, such as the source of adult stem cells, optimal cell types for implantation (universal mesenchymal stem cells vs. tissue-specific stem cells, or induced vs. non-induced stem cells, early or late passages of stem cells, stem cells with endogenous or exogenous growth factors, preconditioning of stem cells (hypoxia, growth factors, or conditioned medium, using various controlled release systems to deliver growth factors with hydrogels or microspheres to provide apposite interactions of stem cells and their niche. We also review several approaches of cell delivery that affect the outcomes of cell therapy, including the appropriate routes of cell administration (systemic, intravenous, or intraperitoneal vs. local administration, timing for cell therapy (immediate vs. a few days after injury, single injection of a large number of cells vs. multiple smaller injections, a single site for injection vs. multiple sites and use of rodents vs. larger animal models. Future directions of stem cell-based therapies are also discussed to guide potential clinical applications.

Transplantation of bone marrow derived cells promotes pancreatic islet repair in diabetic mice

International Nuclear Information System (INIS)

Gao Xiaodong; Song Lujun; Shen Kuntang; Wang Hongshan; Niu Weixin; Qin Xinyu

2008-01-01

The transplantation of bone marrow (BM) derived cells to initiate pancreatic regeneration is an attractive but as-yet unrealized strategy. Presently, BM derived cells from green fluorescent protein transgenic mice were transplanted into diabetic mice. Repair of diabetic islets was evidenced by reduction of hyperglycemia, increase in number of islets, and altered pancreatic histology. Cells in the pancreata of recipient mice co-expressed BrdU and insulin. Double staining revealed β cells were in the process of proliferation. BrdU + insulin - PDX-1 + cells, Ngn3 + cells and insulin + glucagon + cells, which showed stem cells, were also found during β-cell regeneration. The majority of transplanted cells were mobilized to the islet and ductal regions. In recipient pancreas, transplanted cells simultaneously expressed CD34 but did not express insulin, PDX-1, Ngn3, Nkx2.2, Nkx6.1, Pax4, Pax6, and CD45. It is concluded that BM derived cells especially CD34 + cells can promote repair of pancreatic islets. Moreover, both proliferation of β cells and differentiation of pancreatic stem cells contribute to the regeneration of β cells

The phenotype of FancB-mutant mouse embryonic stem cells

OpenAIRE

Kim, Tae Moon; Ko, Jun Ho; Choi, Yong Jun; Hu, Lingchuan; Hasty, Paul

2011-01-01

Fanconi anemia (FA) is a rare autosomal recessive disease characterized by bone marrow failure, developmental defects and cancer. There are multiple FA genes that enable the repair of interstrand crosslinks (ICLs) in coordination with a variety of other DNA repair pathways in a way that is poorly understood. Here we present the phenotype of mouse embryonic stem (ES) cells mutated for FancB. We found FancB-mutant cells exhibited reduced cellular proliferation, hypersensitivity to the crosslink...

Mesenchymal stem cells display different gene expression profiles compared to hyaline and elastic chondrocytes

OpenAIRE

Zhai, Li-Jie; Zhao, Ke-Qing; Wang, Zhi-Qiang; Feng, Ya; Xing, Shuang-Chun

2011-01-01

Cartilage has a poor intrinsic repair capacity, requiring surgical intervention to effect biological repair. Tissue engineering technologies or regenerative medicine strategies are currently being employed to address cartilage repair. Mesenchymal stem cells (MSCs) are considered to be an excellent cell source for this application. However, the different gene expression profiles between the MSCs and differentiated cartilage remain unclear. In this report, we first examined the gene expression ...

The Yin and Yang of chromatin dynamics in adult stem cell fate selection

Science.gov (United States)

Adam, Rene C.; Fuchs, Elaine

2015-01-01

Adult organisms rely on tissue stem cells for maintenance and repair. During homeostasis, the concerted action of local niche signals and epigenetic regulators establish stable gene expression patterns to ensure that stem cells are not lost over time. However, stem cells also provide host tissues with a remarkable plasticity to respond to perturbations. How adult stem cells choose and acquire new fates is unknown, but the genome-wide mapping of epigenetic landscapes suggests a critical role for chromatin remodeling in these processes. Here, we explore the emerging role of chromatin modifiers and pioneer transcription factors in adult stem cell fate decisions and plasticity, which ensure that selective lineage choices are only made when environmentally cued. PMID:26689127

Role of bone marrow-derived stem cells, renal progenitor cells and stem cell factor in chronic renal allograft nephropathy

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Hayam Abdel Meguid El Aggan

2013-09-01

Full Text Available Introduction: Chronic allograft nephropathy (CAN is a poorly understood clinico-pathological entity associated with chronic allograft loss due to immunologic and non-immunologic causes. It remains the leading cause of late allograft loss. Bone marrow derived stem cells are undifferentiated cells typically characterized by their capacity for self renewal, ability to give rise to multiple differentiated cellular population, including hematopoietic (HSCs and mesenchymal stem cells (MSCs. Characterization of HSCs includes their multipotency, expression of typical surface markers such as CD34 and CD45, while characterization of MSC includes their multipotency, expression of typical surface markers such as CD90 and CD105, and the absence of hemopoietic lineage markers. Aim & methods: The aim of the present work was to study the role of bone marrow-derived HSCs and MSCs, renal progenitor cells and SCF in chronic renal allograft nephropathy in relation to renal hemodynamics and histopathological changes. We studied 30 patients with kidney transplantation for more than 6 months, divided into 15 patients with stable serum creatinine and 15 patients who developed CAN. Detection of HSCs and MSCs in the peripheral blood using flow cytometry via detection of CD34, CD45, CD117 and CD106, as well as immunohistochemical detection of CD34, CD133, VEGF and αSMA in transplanted kidney biopsies of patients with CAN were done. Results: There was a significant increase in the levels of SCF, number of peripheral blood HSCs and MSCs in both transplanted patient groups than the controls and they were higher in patients of group Ia than patients of group Ib, (F = 39.73, P < 0.001, (F = 13.28, P < 0.001, (F = 11.94, P < 0.001, respectively and this was accompanied by evident expression of markers of renal repair. Conclusion: Stem cells might have a role in renal regeneration in CAN and this may pave the way toward the use of stem cells in correction of CAN. KEYWORDS

Detection of Repair of the Zone of Calcified Cartilage with Osteoarthritis through Mesenchymal Stem Cells by Ultrashort Echo Time Magnetic Resonance Imaging.

Science.gov (United States)

Zhou, Quan; Li, Shao-Lin; Ma, Ya-Jun; de Tal, Vicki; Li, Wei; Zhao, Ying-Hua

2018-05-05

Currently, magnetic resonance imaging (MRI) is the most commonly used imaging modality for observing the growth and development of mesenchymal stem cells (MSCs) after in vivo transplantation to treat osteoarthritis (OA). However, it is a challenge to accurately monitor the treatment effects of MSCs in the zone of calcified cartilage (ZCC) with OA. This is especially true in the physiological and biochemical views that are not accurately detected by MRI contrast agents. In contrast, ultrashort time echo (UTE) MRI has been shown to be sensitive to the presence of the ZCC, creating the potential for more effectively observing the repair of the ZCC in OA by MSCs. A special focus is given to the outlook of the use of UTE MRI to detect repair of the ZCC with OA through MSCs. The limitations of the current techniques for clinical applications and future directions are also discussed. Using the combined keywords: "osteoarthritis", "mesenchymal stem cells", "calcified cartilage", and "magnetic resonance imaging", the PubMed/MEDLINE literature search was conducted up to June 1, 2017. A total of 132 published articles were initially identified citations. Of the 132 articles, 48 articles were selected after further detailed review. This study referred to all the important English literature in full. In contrast, UTE MRI has been shown to be sensitive to the presence of the ZCC, creating the potential for more effectively observing the repair of the ZCC in OA by MSCs. The current studies showed that the ZCC could be described in terms of its histomorphology and biochemistry by UTE MRI. We prospected that UTE MRI has been shown the potential for more effectively observing the repair of the ZCC in OA by MSCs in vivo.

Progenitor/stem cell transplantation for repair of myocardial infarction: Hype or hope?

OpenAIRE

Feng, Yuliang; Wang, Yuhua; Cao, Nan; Yang, Huangtian; Wang, Yigang

2012-01-01

Despite significant therapeutic advances, heart failure remains the predominant cause of mortality worldwide. Currently, progenitor/stem cell biology holds great promise for a new era of cell-based therapy for salvaging the failing heart. However, the translational arm of progenitor/stem cell science is in a relatively primitive state. For the time being, the clinical trials have been both encouraging and disappointing. How to improve the engraftment, long-term survival and appropriate differ...

Lineage tracing in the adult mouse corneal epithelium supports the limbal epithelial stem cell hypothesis with intermittent periods of stem cell quiescence

Directory of Open Access Journals (Sweden)

Natalie J. Dorà

2015-11-01

Full Text Available The limbal epithelial stem cell (LESC hypothesis proposes that LESCs in the corneal limbus maintain the corneal epithelium both during normal homeostasis and wound repair. The alternative corneal epithelial stem cell (CESC hypothesis proposes that LESCs are only involved in wound repair and CESCs in the corneal epithelium itself maintain the corneal epithelium during normal homeostasis. We used tamoxifen-inducible, CreER-loxP lineage tracing to distinguish between these hypotheses. Clones of labelled cells were induced in adult CAGG-CreER;R26R-LacZ reporter mice and their distributions analysed after different chase periods. Short-lived clones, derived from labelled transient amplifying cells, were shed during the chase period and long-lived clones, derived from stem cells, expanded. At 6 weeks, labelled clones appeared at the periphery, extended centripetally as radial stripes and a few reached the centre by 14 weeks. Stripe numbers depended on the age of tamoxifen treatment. Stripes varied in length, some were discontinuous, few reached the centre and almost half had one end at the limbus. Similar stripes extended across the cornea in CAGG-CreER;R26R-mT/mG reporter mice. The distributions of labelled clones are inconsistent with the CESC hypothesis and support the LESC hypothesis if LESCs cycle between phases of activity and quiescence, each lasting several weeks.

Molecular Imaging in Stem Cell Therapy for Spinal Cord Injury

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Fahuan Song

2014-01-01

Full Text Available Spinal cord injury (SCI is a serious disease of the center nervous system (CNS. It is a devastating injury with sudden loss of motor, sensory, and autonomic function distal to the level of trauma and produces great personal and societal costs. Currently, there are no remarkable effective therapies for the treatment of SCI. Compared to traditional treatment methods, stem cell transplantation therapy holds potential for repair and functional plasticity after SCI. However, the mechanism of stem cell therapy for SCI remains largely unknown and obscure partly due to the lack of efficient stem cell trafficking methods. Molecular imaging technology including positron emission tomography (PET, magnetic resonance imaging (MRI, optical imaging (i.e., bioluminescence imaging (BLI gives the hope to complete the knowledge concerning basic stem cell biology survival, migration, differentiation, and integration in real time when transplanted into damaged spinal cord. In this paper, we mainly review the molecular imaging technology in stem cell therapy for SCI.

Genetic modification of stem cells for transplantation.

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Phillips, M Ian; Tang, Yao Liang

2008-01-14

Gene modification of cells prior to their transplantation, especially stem cells, enhances their survival and increases their function in cell therapy. Like the Trojan horse, the gene-modified cell has to gain entrance inside the host's walls and survive and deliver its transgene products. Using cellular, molecular and gene manipulation techniques the transplanted cell can be protected in a hostile environment from immune rejection, inflammation, hypoxia and apoptosis. Genetic engineering to modify cells involves constructing modules of functional gene sequences. They can be simple reporter genes or complex cassettes with gene switches, cell specific promoters and multiple transgenes. We discuss methods to deliver and construct gene cassettes with viral and non-viral delivery, siRNA, and conditional Cre/Lox P. We review the current uses of gene-modified stem cells in cardiovascular disease, diabetes, neurological diseases, (including Parkinson's, Alzheimer's and spinal cord injury repair), bone defects, hemophilia, and cancer.

Neural Stem Cells: Implications for the Conventional Radiotherapy of Central Nervous System Malignancies

International Nuclear Information System (INIS)

Barani, Igor J.; Benedict, Stanley H.; Lin, Peck-Sun

2007-01-01

Advances in basic neuroscience related to neural stem cells and their malignant counterparts are challenging traditional models of central nervous system tumorigenesis and intrinsic brain repair. Neurogenesis persists into adulthood predominantly in two neurogenic centers: subventricular zone and subgranular zone. Subventricular zone is situated adjacent to lateral ventricles and subgranular zone is confined to the dentate gyrus of the hippocampus. Neural stem cells not only self-renew and differentiate along multiple lineages in these regions, but also contribute to intrinsic brain plasticity and repair. Ionizing radiation can depopulate these exquisitely sensitive regions directly or impair in situ neurogenesis by indirect, dose-dependent and inflammation-mediated mechanisms, even at doses <2 Gy. This review discusses the fundamental neural stem cell concepts within the framework of cumulative clinical experience with the treatment of central nervous system malignancies using conventional radiotherapy

Stem Cells

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Stem cells are cells with the potential to develop into many different types of cells in the body. ... the body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

Stem Cell-Derived Exosome in Cardiovascular Diseases: Macro Roles of Micro Particles.

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Yuan, Ye; Du, Weijie; Liu, Jiaqi; Ma, Wenya; Zhang, Lai; Du, Zhimin; Cai, Benzhi

2018-01-01

The stem cell-based therapy has emerged as the promising therapeutic strategies for cardiovascular diseases (CVDs). Recently, increasing evidence suggest stem cell-derived active exosomes are important communicators among cells in the heart via delivering specific substances to the adjacent/distant target cells. These exosomes and their contents such as certain proteins, miRNAs and lncRNAs exhibit huge beneficial effects on preventing heart damage and promoting cardiac repair. More importantly, stem cell-derived exosomes are more effective and safer than stem cell transplantation. Therefore, administration of stem cell-derived exosomes will expectantly be an alternative stem cell-based therapy for the treatment of CVDs. Furthermore, modification of stem cell-derived exosomes or artificial synthesis of exosomes will be the new therapeutic tools for CVDs in the future. In addition, stem cell-derived exosomes also have been implicated in the diagnosis and prognosis of CVDs. In this review, we summarize the current advances of stem cell-derived exosome-based treatment and prognosis for CVDs, including their potential benefits, underlying mechanisms and limitations, which will provide novel insights of exosomes as a new tool in clinical therapeutic translation in the future.

DNA repair , cell repair and radiosensitivity

International Nuclear Information System (INIS)

Zhestyanikov, V.D.

1983-01-01

Data obtained in laboratory of radiation cytology and literature data testifying to a considerable role of DNA repair in cell sensitivity to radiation and chemical DNA-tropic agents have been considered. Data pointing to the probability of contribution of inducible repair of DNA into plant cells sensitivity to X-rays are obtained. Certain violations of DNA repair do not result in the increase of radiosensitivity. It is assumed that in the cases unknown mechanisms of DNA repair operate

Stem cells: roadmap to the clinic

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Daley, George Q.

2010-01-01

Over the last decade, a remarkable number of papers have been published in which the biology of stem cells is introduced with words and phrases such as “promise,” “rapid progress,” and “future therapies.” To separate myth and hype from reality, the articles in this Stem Cells Review series comprise a rich resource on the state of this fast-paced field and provide a balanced perspective on some of the major advances. They recount what the field has achieved over the past decade and where the field is headed. They also highlight the challenges to be faced in translating what is indeed highly promising science into proven therapies that will regenerate and repair diseased tissues. PMID:20051631

Differentiation of hepatocytes from induced pluripotent stem cells derived from human hair follicle mesenchymal stem cells.

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Shi, Xu; Lv, Shuang; He, Xia; Liu, Xiaomei; Sun, Meiyu; Li, Meiying; Chi, Guangfan; Li, Yulin

2016-10-01

Due to the limitations of organ donors and immune rejection in severe liver diseases, stem cell-based therapy presents a promising application for tissue repair and regeneration. As a novel cell source, mesenchymal stem cells separated from human hair follicles (HF-MSCs) are convenient to obtain and have no age limit. To date, the differentiation of HF-MSCs into hepatocytes has not been reported. In this study, we explored whether HF-MSCs and HF-MSC-derived-induced pluripotent stem cells (HF-iPS) could differentiate into hepatocytes in vitro. Flow cytometry, Oil Red O stain and Alizarin Red stain were used to identify the characteristics of HF-MSCs. The expression of liver-specific gene was detected by immunofluorescence and Quantitative Polymerase Chain Reaction. Periodic Acid-Schiff stain, Indocyanine Green stain and Low-Density Lipoprotein stain were performed to evaluate the functions of induced hepatocyte-like cells (HLCs). HF-MSCs were unable to differentiate into HLCs using previously reported procedures for MSCs from other tissues. However, HF-iPS efficiently induced the generation of HLCs that expressed hepatocyte markers and drug metabolism-related genes. HF-iPS can be used as novel and alternative cellular tools for inducing hepatocytes in vitro, simultaneously benefiting from utilizing HF-MSCs as a noninvasive and convenient cell source for reprogramming.

Proteomics-based network analysis characterizes biological processes and pathways activated by preconditioned mesenchymal stem cells in cardiac repair mechanisms.

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Di Silvestre, Dario; Brambilla, Francesca; Scardoni, Giovanni; Brunetti, Pietro; Motta, Sara; Matteucci, Marco; Laudanna, Carlo; Recchia, Fabio A; Lionetti, Vincenzo; Mauri, Pierluigi

2017-05-01

We have demonstrated that intramyocardial delivery of human mesenchymal stem cells preconditioned with a hyaluronan mixed ester of butyric and retinoic acid (MSCp + ) is more effective in preventing the decay of regional myocardial contractility in a swine model of myocardial infarction (MI). However, the understanding of the role of MSCp + in proteomic remodeling of cardiac infarcted tissue is not complete. We therefore sought to perform a comprehensive analysis of the proteome of infarct remote (RZ) and border zone (BZ) of pigs treated with MSCp + or unconditioned stem cells. Heart tissues were analyzed by MudPIT and differentially expressed proteins were selected by a label-free approach based on spectral counting. Protein profiles were evaluated by using PPI networks and their topological analysis. The proteomic remodeling was largely prevented in MSCp + group. Extracellular proteins involved in fibrosis were down-regulated, while energetic pathways were globally up-regulated. Cardioprotectant pathways involved in the production of keto acid metabolites were also activated. Additionally, we found that new hub proteins support the cardioprotective phenotype characterizing the left ventricular BZ treated with MSCp + . In fact, the up-regulation of angiogenic proteins NCL and RAC1 can be explained by the increase of capillary density induced by MSCp + . Our results show that angiogenic pathways appear to be uniquely positioned to integrate signaling with energetic pathways involving cardiac repair. Our findings prompt the use of proteomics-based network analysis to optimize new approaches preventing the post-ischemic proteomic remodeling that may underlie the limited self-repair ability of adult heart. Copyright © 2017 Elsevier B.V. All rights reserved.

Stem Cell Therapy: A Promising Therapeutic Method for Intracerebral Hemorrhage.

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Gao, Liansheng; Xu, Weilin; Li, Tao; Chen, Jingyin; Shao, Anwen; Yan, Feng; Chen, Gao

2018-01-01

Spontaneous intracerebral hemorrhage (ICH) is one type of the most devastating cerebrovascular diseases worldwide, which causes high morbidity and mortality. However, efficient treatment is still lacking. Stem cell therapy has shown good neuroprotective and neurorestorative effect in ICH and is a promising treatment. In this study, our aim was to review the therapeutic effects, strategies, related mechanisms and safety issues of various types of stem cell for ICH treatment. Numerous studies had demonstrated the therapeutic effects of diverse stem cell types in ICH. The potential mechanisms include tissue repair and replacement, neurotrophy, promotion of neurogenesis and angiogenesis, anti-apoptosis, immunoregulation and anti-inflammation and so forth. The microenvironment of the central nervous system (CNS) can also influence the effects of stem cell therapy. The detailed therapeutic strategies for ICH treatment such as cell type, the number of cells, time window, and the routes of medication delivery, varied greatly among different studies and had not been determined. Moreover, the safety issues of stem cell therapy for ICH should not be ignored. Stem cell therapy showed good therapeutic effect in ICH, making it a promising treatment. However, safety should be carefully evaluated, and more clinical trials are required before stem cell therapy can be extensively applied to clinical use.

Designing the stem cell microenvironment for guided connective tissue regeneration.

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Bogdanowicz, Danielle R; Lu, Helen H

2017-12-01

Adult mesenchymal stem cells (MSCs) are an attractive cell source for regenerative medicine because of their ability to self-renew and their capacity for multilineage differentiation and tissue regeneration. For connective tissues, such as ligaments or tendons, MSCs are vital to the modulation of the inflammatory response following acute injury while also interacting with resident fibroblasts to promote cell proliferation and matrix synthesis. To date, MSC injection for connective tissue repair has yielded mixed results in vivo, likely due to a lack of appropriate environmental cues to effectively control MSC response and promote tissue healing instead of scar formation. In healthy tissues, stem cells reside within a complex microenvironment comprising cellular, structural, and signaling cues that collectively maintain stemness and modulate tissue homeostasis. Changes to the microenvironment following injury regulate stem cell differentiation, trophic signaling, and tissue healing. Here, we focus on models of the stem cell microenvironment that are used to elucidate the mechanisms of stem cell regulation and inspire functional approaches to tissue regeneration. Recent studies in this frontier area are highlighted, focusing on how microenvironmental cues modulate MSC response following connective tissue injury and, more importantly, how this unique cell environment can be programmed for stem cell-guided tissue regeneration. © 2017 New York Academy of Sciences.

Human adipose-derived stem cells: definition, isolation, tissue-engineering applications.

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Nae, S; Bordeianu, I; Stăncioiu, A T; Antohi, N

2013-01-01

Recent researches have demonstrated that the most effective repair system of the body is represented by stem cells - unspecialized cells, capable of self-renewal through successive mitoses, which have also the ability to transform into different cell types through differentiation. The discovery of adult stem cells represented an important step in regenerative medicine because they no longer raises ethical or legal issues and are more accessible. Only in 2002, stem cells isolated from adipose tissue were described as multipotent stem cells. Adipose tissue stem cells benefits in tissue engineering and regenerative medicine are numerous. Development of adipose tissue engineering techniques offers a great potential in surpassing the existing limits faced by the classical approaches used in plastic and reconstructive surgery. Adipose tissue engineering clinical applications are wide and varied, including reconstructive, corrective and cosmetic procedures. Nowadays, adipose tissue engineering is a fast developing field, both in terms of fundamental researches and medical applications, addressing issues related to current clinical pathology or trauma management of soft tissue injuries in different body locations.

Visual bone marrow mesenchymal stem cell transplantation in the repair of spinal cord injury

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Rui-ping Zhang

2015-01-01

Full Text Available An important factor in improving functional recovery from spinal cord injury using stem cells is maximizing the number of transplanted cells at the lesion site. Here, we established a contusion model of spinal cord injury by dropping a weight onto the spinal cord at T 7-8 . Superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells were transplanted into the injured spinal cord via the subarachnoid space. An outer magnetic field was used to successfully guide the labeled cells to the lesion site. Prussian blue staining showed that more bone marrow mesenchymal stem cells reached the lesion site in these rats than in those without magnetic guidance or superparamagnetic iron oxide labeling, and immunofluorescence revealed a greater number of complete axons at the lesion site. Moreover, the Basso, Beattie and Bresnahan (BBB locomotor rating scale scores were the highest in rats with superparamagnetic labeling and magnetic guidance. Our data confirm that superparamagnetic iron oxide nanoparticles effectively label bone marrow mesenchymal stem cells and impart sufficient magnetism to respond to the external magnetic field guides. More importantly, superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells can be dynamically and non-invasively tracked in vivo using magnetic resonance imaging. Superparamagnetic iron oxide labeling of bone marrow mesenchymal stem cells coupled with magnetic guidance offers a promising avenue for the clinical treatment of spinal cord injury.

Priming of the Cells: Hypoxic Preconditioning for Stem Cell Therapy.

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Wei, Zheng Z; Zhu, Yan-Bing; Zhang, James Y; McCrary, Myles R; Wang, Song; Zhang, Yong-Bo; Yu, Shan-Ping; Wei, Ling

2017-10-05

Stem cell-based therapies are promising in regenerative medicine for protecting and repairing damaged brain tissues after injury or in the context of chronic diseases. Hypoxia can induce physiological and pathological responses. A hypoxic insult might act as a double-edged sword, it induces cell death and brain damage, but on the other hand, sublethal hypoxia can trigger an adaptation response called hypoxic preconditioning or hypoxic tolerance that is of immense importance for the survival of cells and tissues. This review was based on articles published in PubMed databases up to August 16, 2017, with the following keywords: "stem cells," "hypoxic preconditioning," "ischemic preconditioning," and "cell transplantation." Original articles and critical reviews on the topics were selected. Hypoxic preconditioning has been investigated as a primary endogenous protective mechanism and possible treatment against ischemic injuries. Many cellular and molecular mechanisms underlying the protective effects of hypoxic preconditioning have been identified. In cell transplantation therapy, hypoxic pretreatment of stem cells and neural progenitors markedly increases the survival and regenerative capabilities of these cells in the host environment, leading to enhanced therapeutic effects in various disease models. Regenerative treatments can mobilize endogenous stem cells for neurogenesis and angiogenesis in the adult brain. Furthermore, transplantation of stem cells/neural progenitors achieves therapeutic benefits via cell replacement and/or increased trophic support. Combinatorial approaches of cell-based therapy with additional strategies such as neuroprotective protocols, anti-inflammatory treatment, and rehabilitation therapy can significantly improve therapeutic benefits. In this review, we will discuss the recent progress regarding cell types and applications in regenerative medicine as well as future applications.

Aberrant repair and fibrosis development in skeletal muscle

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Mann Christopher J

2011-05-01

Full Text Available Abstract The repair process of damaged tissue involves the coordinated activities of several cell types in response to local and systemic signals. Following acute tissue injury, infiltrating inflammatory cells and resident stem cells orchestrate their activities to restore tissue homeostasis. However, during chronic tissue damage, such as in muscular dystrophies, the inflammatory-cell infiltration and fibroblast activation persists, while the reparative capacity of stem cells (satellite cells is attenuated. Abnormal dystrophic muscle repair and its end stage, fibrosis, represent the final common pathway of virtually all chronic neurodegenerative muscular diseases. As our understanding of the pathogenesis of muscle fibrosis has progressed, it has become evident that the muscle provides a useful model for the regulation of tissue repair by the local microenvironment, showing interplay among muscle-specific stem cells, inflammatory cells, fibroblasts and extracellular matrix components of the mammalian wound-healing response. This article reviews the emerging findings of the mechanisms that underlie normal versus aberrant muscle-tissue repair.