Sample records for stem cell replacement

  1. Adult subventricular zone neural stem cells as a potential source of dopaminergic replacement neurons

    PubMed Central

    Cave, John W.; Wang, Meng; Baker, Harriet

    2014-01-01

    Clinical trials engrafting human fetal ventral mesencephalic tissue have demonstrated, in principle, that cell replacement therapy provides substantial long-lasting improvement of motor impairments generated by Parkinson's Disease (PD). The use of fetal tissue is not practical for widespread clinical implementation of this therapy, but stem cells are a promising alternative source for obtaining replacement cells. The ideal stem cell source has yet to be established and, in this review, we discuss the potential of neural stem cells in the adult subventricular zone (SVZ) as an autologous source of replacement cells. We identify three key challenges for further developing this potential source of replacement cells: (1) improving survival of transplanted cells, (2) suppressing glial progenitor proliferation and survival, and (3) developing methods to efficiently produce dopaminergic neurons. Subventricular neural stem cells naturally produce a dopaminergic interneuron phenotype that has an apparent lack of vulnerability to PD-mediated degeneration. We also discuss whether olfactory bulb dopaminergic neurons derived from adult SVZ neural stem cells are a suitable source for cell replacement strategies. PMID:24574954

  2. Stem cell treatment of degenerative eye disease.

    PubMed

    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.

  3. Estrogen deficiency heterogeneously affects tissue specific stem cells in mice

    PubMed Central

    Kitajima, Yuriko; Doi, Hanako; Ono, Yusuke; Urata, Yoshishige; Goto, Shinji; Kitajima, Michio; Miura, Kiyonori; Li, Tao-Sheng; Masuzaki, Hideaki

    2015-01-01

    Postmenopausal disorders are frequently observed in various organs, but their relationship with estrogen deficiency and mechanisms remain unclear. As tissue-specific stem cells have been found to express estrogen receptors, we examined the hypothesis that estrogen deficiency impairs stem cells, which consequently contributes to postmenopausal disorders. Six-week-old C57BL/6 female mice were ovariectomized, following which they received 17β-estradiol replacement or vehicle (control). Sham-operated mice were used as healthy controls. All mice were killed for evaluation 2 months after treatments. Compared with the healthy control, ovariectomy significantly decreased uterine weight, which was partially recovered by 17β-estradiol replacement. Ovariectomy significantly increased the numbers of c-kit-positive hematopoietic stem/progenitor cells in bone marrow, but impaired their capacity to grow mixed cell-type colonies in vitro. Estrogen replacement further increased the numbers of c-kit-positive hematopoietic stem/progenitor cells in bone marrow, without significantly affecting colony growth in vitro. The number of CD105-positive mesenchymal stem cells in bone marrow also significantly decreased after ovariectomy, but completely recovered following estrogen replacement. Otherwise, neither ovariectomy nor estrogen replacement changed the number of Pax7-positive satellite cells, which are a skeletal muscle-type stem cell. Estrogen deficiency heterogeneously affected tissue-specific stem cells, suggesting a likely and direct relationship with postmenopausal disorders. PMID:26245252

  4. Tooth replacement without a dental lamina: the search for epithelial stem cells in Polypterus senegalus.

    PubMed

    Vandenplas, Sam; De Clercq, Adelbert; Huysseune, Ann

    2014-07-01

    Most actinopterygians replace their teeth continuously throughout life. To address the question of where and how replacement teeth form in actinopterygians, it is advisable to investigate well-chosen representatives within the lineage. The African bichir, Polypterus senegalus, belongs to the earliest diverged group of the actinopterygian lineage with currently living representatives. Its well characterized dentition, together with its phylogenetic position, make this species an attractive model to answer following questions: (1) when and where does the replacement tooth form and how is it connected with the dental organ of the predecessor, and (2) is there any evidence for the presence of epithelial stem cells, hypothesized to play a role in replacement? Serial sections show that one tooth family can contain up to three members, which are all interconnected by dental epithelium. Replacement teeth develop without the presence of a successional dental lamina. We propose that this is the plesiomorphic condition for tooth replacement in actinopterygians. BrdU pulse-chase experiments reveal cells in the outer and middle dental epithelium, proliferating at the time of initiation of a new replacement tooth. It is tempting to assume that these cell layers provide a stem cell niche. The observed absence of label-retaining cells after long chase times (up to 8 weeks) is held against the light of divergent views on cell cycling properties of stem cells. At present, our data do not support, neither reject, the hypothesis on involvement of epithelial stem cells within the process of continuous tooth replacement. © 2014 Wiley Periodicals, Inc.

  5. Serum replacement with a growth factor-free synthetic substance in culture medium contributes to effective establishment of mouse embryonic stem cells of various origins.

    PubMed

    Lee, Seung Tae; Oh, Se Woong; Kim, Dae Yong; Han, Jae Yong; Moon, Shin Yong; Lim, Jeong Mook

    2006-10-01

    To evaluate whether serum replacement with growth factor-free synthetic substances contributed to the effective establishment of embryonic stem (ES) cells. Randomized, prospective model study. Gamete and stem cell biotechnology laboratory at Seoul National University in Korea. F1 (C57BL6 x DBA2) mice. Blastocysts of different origins were cultured in serum-replaced media. Embryonic stem cell establishment. Eight batches of ES cells were established from colony-forming inner cell mass cells after the replacement of fetal bovine serum (FBS) with synthetic knockout serum replacement (KSR) in mkDMEM. The established cells were positive for ES cell markers and formed both embryoid bodies in vitro and teratomas in vivo, but the established cell batches and control (transformed) ES cells responded differently to the culture media. Higher levels of cell viability were detected after the replacement with the 75:25 FBS-KSR mixture than with any other mixtures, and a gradual decrease in viability was detected as the KSR volume ratio was increased. The 75:25 FBS-KSR mixture-containing medium supported ES cell establishment of outbred ICR, F1, and F2 of C57BL6/DBA2; F1 parthenogenetic and ES cell-complemented tetraploid blastocysts; and single ES-cell cultures. A serum-replaced medium could be used for effective ES-cell establishment of various origins.

  6. β-Cell Replacement in Mice Using Human Type 1 Diabetes Nuclear Transfer Embryonic Stem Cells.

    PubMed

    Sui, Lina; Danzl, Nichole; Campbell, Sean R; Viola, Ryan; Williams, Damian; Xing, Yuan; Wang, Yong; Phillips, Neil; Poffenberger, Greg; Johannesson, Bjarki; Oberholzer, Jose; Powers, Alvin C; Leibel, Rudolph L; Chen, Xiaojuan; Sykes, Megan; Egli, Dieter

    2018-01-01

    β-Cells derived from stem cells hold great promise for cell replacement therapy for diabetes. Here we examine the ability of nuclear transfer embryonic stem cells (NT-ESs) derived from a patient with type 1 diabetes to differentiate into β-cells and provide a source of autologous islets for cell replacement. NT-ESs differentiate in vitro with an average efficiency of 55% into C-peptide-positive cells, expressing markers of mature β-cells, including MAFA and NKX6.1. Upon transplantation in immunodeficient mice, grafted cells form vascularized islet-like structures containing MAFA/C-peptide-positive cells. These β-cells adapt insulin secretion to ambient metabolite status and show normal insulin processing. Importantly, NT-ES-β-cells maintain normal blood glucose levels after ablation of the mouse endogenous β-cells. Cystic structures, but no teratomas, were observed in NT-ES-β-cell grafts. Isogenic induced pluripotent stem cell lines showed greater variability in β-cell differentiation. Even though different methods of somatic cell reprogramming result in stem cell lines that are molecularly indistinguishable, full differentiation competence is more common in ES cell lines than in induced pluripotent stem cell lines. These results demonstrate the suitability of NT-ES-β-cells for cell replacement for type 1 diabetes and provide proof of principle for therapeutic cloning combined with cell therapy. © 2017 by the American Diabetes Association.

  7. Fully functional hair follicle regeneration through the rearrangement of stem cells and their niches

    PubMed Central

    Toyoshima, Koh-ei; Asakawa, Kyosuke; Ishibashi, Naoko; Toki, Hiroshi; Ogawa, Miho; Hasegawa, Tomoko; Irié, Tarou; Tachikawa, Tetsuhiko; Sato, Akio; Takeda, Akira; Tsuji, Takashi

    2012-01-01

    Organ replacement regenerative therapy is purported to enable the replacement of organs damaged by disease, injury or aging in the foreseeable future. Here we demonstrate fully functional hair organ regeneration via the intracutaneous transplantation of a bioengineered pelage and vibrissa follicle germ. The pelage and vibrissae are reconstituted with embryonic skin-derived cells and adult vibrissa stem cell region-derived cells, respectively. The bioengineered hair follicle develops the correct structures and forms proper connections with surrounding host tissues such as the epidermis, arrector pili muscle and nerve fibres. The bioengineered follicles also show restored hair cycles and piloerection through the rearrangement of follicular stem cells and their niches. This study thus reveals the potential applications of adult tissue-derived follicular stem cells as a bioengineered organ replacement therapy. PMID:22510689

  8. Continuous tooth replacement: the possible involvement of epithelial stem cells.

    PubMed

    Huysseune, Ann; Thesleff, Irma

    2004-06-01

    Epithelial stem cells have been identified in integumental structures such as hairs and continuously growing teeth of various rodents, and in the gut. Here we propose the involvement of epithelial stem cells in the continuous tooth replacement that characterizes non-mammalian vertebrates, as exemplified by the zebrafish. Arguments are based on morphological observations of tooth renewal in the zebrafish and on the similarities between molecular control of hair and tooth formation. Dissection of the molecular cascades underlying the regulation of the epithelial stem cell niche might open perspectives for new regenerative treatment strategies in clinical dentistry. Copyright 2004 Wiley Periodicals, Inc.

  9. Replacement of Lost Lgr5-Positive Stem Cells through Plasticity of Their Enterocyte-Lineage Daughters.

    PubMed

    Tetteh, Paul W; Basak, Onur; Farin, Henner F; Wiebrands, Kay; Kretzschmar, Kai; Begthel, Harry; van den Born, Maaike; Korving, Jeroen; de Sauvage, Frederic; van Es, Johan H; van Oudenaarden, Alexander; Clevers, Hans

    2016-02-04

    Intestinal crypts display robust regeneration upon injury. The relatively rare secretory precursors can replace lost stem cells, but it is unknown if the abundant enterocyte progenitors that express the Alkaline phosphate intestinal (Alpi) gene also have this capacity. We created an Alpi-IRES-CreERT2 (Alpi(CreER)) knockin allele for lineage tracing. Marked clones consist entirely of enterocytes and are all lost from villus tips within days. Genetic fate-mapping of Alpi(+) cells before or during targeted ablation of Lgr5-expressing stem cells generated numerous long-lived crypt-villus "ribbons," indicative of dedifferentiation of enterocyte precursors into Lgr5(+) stems. By single-cell analysis of dedifferentiating enterocytes, we observed the generation of Paneth-like cells and proliferative stem cells. We conclude that the highly proliferative, short-lived enterocyte precursors serve as a large reservoir of potential stem cells during crypt regeneration. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Generation of functional organs from stem cells.

    PubMed

    Liu, Yunying; Yang, Ru; He, Zuping; Gao, Wei-Qiang

    2013-01-01

    We are now well entering the exciting era of stem cells. Potential stem cell therapy holds great promise for the treatment of many diseases such as stroke, traumatic brain injury, Alzheimer's disease, Parkinson's disease, amyotrophic lateral-sclerosis, myocardial infarction, muscular dystrophy, diabetes, and etc. It is generally believed that transplantation of specific stem cells into the injured tissue to replace the lost cells is an effective way to repair the tissue. In fact, organ transplantation has been successfully practiced in clinics for liver or kidney failure. However, the severe shortage of donor organs has been a major obstacle for the expansion of organ transplantation programs. Toward that direction, generation of transplantable organs using stem cells is a desirable approach for organ replacement and would be of great interest for both basic and clinical scientists. Here we review recent progress in the field of organ generation using various methods including single adult tissue stem cells, a blastocyst complementation system, tissue decellularization/recellularization and a combination of stem cells and tissue engineering.

  11. The quest for tissue stem cells in the pancreas and other organs, and their application in beta-cell replacement.

    PubMed

    Houbracken, Isabelle; Bouwens, Luc

    2010-01-01

    Adult stem cell research has drawn a lot of attention by many researchers, due to its medical hope of cell replacement or regenerative therapy for diabetes patients. Despite the many research efforts to date, there is no consensus on the existence of stem cells in adult pancreas. Genetic lineage tracing experiments have put into serious doubt whether β-cell neogenesis from stem/progenitor cells takes place postnatally. Different in vitro experiments have suggested centroacinar, ductal, acinar, stellate, or yet unidentified clonigenic cells as candidate β-cell progenitors. As in the rest of the adult stem cell field, sound and promising observations have been made. However, these observations still need to be replicated. As an alternative to committed stem/progenitor cells in the pancreas, transdifferentiation or lineage reprogramming of exocrine acinar and endocrine α-cells may be used to generate new β-cells. At present, it is unclear which approach is most medically promising. This article highlights the progress being made in knowledge about tissue stem cells, their existence and availability for therapy in diabetes. Particular attention is given to the assessment of methods to verify the existence of tissue stem cells.

  12. Drosophila Glypicans Regulate Follicle Stem Cell Maintenance and Niche Competition.

    PubMed

    Su, Tsu-Yi; Nakato, Eriko; Choi, Pui Yee; Nakato, Hiroshi

    2018-04-09

    Adult stem cells reside in specialized microenvironments, called niches, which provide signals for stem cells to maintain their undifferentiated and self-renewing state. To maintain stem cell quality, several types of stem cells are known to be regularly replaced by progenitor cells through niche competition. However, the cellular and molecular bases for stem cell competition for niche occupancy are largely unknown. Here, we show that two Drosophila members of the glypican family of heparan sulfate proteoglycans (HSPGs), Dally and Dally-like (Dlp), differentially regulate follicle stem cell (FSC) maintenance and FSC competitiveness for niche occupancy. Lineage analyses of glypican mutant FSC clones showed that dally is essential for normal FSC maintenance. In contrast, dlp is a hyper-competitive mutation: dlp mutant FSC progenitors often eventually occupy the entire epithelial sheet. RNAi knockdown experiments showed that Dally and Dlp play both partially redundant and distinct roles in regulating Jak/Stat, Wg and Hh signaling in FSCs. The Drosophila FSC system offers a powerful genetic model to study the mechanisms by which HSPGs exert specific functions in stem cell replacement and competition. Copyright © 2018, Genetics.

  13. Induced Pluripotent Stem Cell Therapies for Degenerative Disease of the Outer Retina: Disease Modeling and Cell Replacement.

    PubMed

    Di Foggia, Valentina; Makwana, Priyanka; Ali, Robin R; Sowden, Jane C

    2016-06-01

    Stem cell therapies are being explored as potential treatments for retinal disease. How to replace neurons in a degenerated retina presents a continued challenge for the regenerative medicine field that, if achieved, could restore sight. The major issues are: (i) the source and availability of donor cells for transplantation; (ii) the differentiation of stem cells into the required retinal cells; and (iii) the delivery, integration, functionality, and survival of new cells in the host neural network. This review considers the use of induced pluripotent stem cells (iPSC), currently under intense investigation, as a platform for cell transplantation therapy. Moreover, patient-specific iPSC are being developed for autologous cell transplantation and as a tool for modeling specific retinal diseases, testing gene therapies, and drug screening.

  14. Tissue engineering, stem cells and cloning: current concepts and changing trends.

    PubMed

    Atala, Anthony

    2005-07-01

    Organ damage or loss can occur from congenital disorders, cancer, trauma, infection, inflammation, iatrogenic injuries or other conditions and often necessitates reconstruction or replacement. Replacement may take the form of organ transplant. At present, there is a severe shortage of donor organs that is worsening with the aging of the population. Tissue engineering follows the principles of cell transplantation, materials science and engineering towards the development of biological substitutes that can restore and maintain normal tissue function. Therapeutic cloning involves the introduction of a nucleus from a donor cell into an enucleated oocyte to generate embryonic stem cell lines whose genetic material is identical to that of its source. These autologous stem cells have the potential to become almost any type of cell in the adult body, and thus would be useful in tissue and organ replacement applications. This paper reviews recent advances in stem cell research and regenerative medicine, and describes the clinical applications of these technologies as novel therapies for tissue or organ loss.

  15. Mesenchymal Stem Cells as a Source of Dopaminergic Neurons: A Potential Cell Based Therapy for Parkinson's Disease.

    PubMed

    Venkatesh, Katari; Sen, Dwaipayan

    2017-01-01

    Cell repair/replacing strategies for neurodegenerative diseases such as Parkinson's disease depend on well-characterized dopaminergic neuronal candidates that are healthy and show promising effect on the rejuvenation of degenerated area of the brain. Therefore, it is imperative to develop innovative therapeutic strategies that replace damaged neurons with new/functional dopaminergic neurons. Although several research groups have reported the generation of neural precursors/neurons from human/ mouse embryonic stem cells and mesenchymal stem cells, the latter is considered to be an attractive therapeutic candidate because of its high capacity for self-renewable, no adverse effect to allogeneic versus autologous transplants, high ethical acceptance and no teratoma formation. Therefore, mesenchymal stem cells can be considered as an ideal source for replacing lost cells in degenerative diseases like Parkinson's. Hence, the use of these cells in the differentiation of dopaminergic neurons becomes significant and thrives as a therapeutic approach to treat Parkinson's disease. Here we highlight the basic biology of mesenchymal stem cells, their differentiation potential into dopaminergic neurons and potential use in the clinics. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  16. Stem cell-based therapies in Parkinson's disease: future hope or current treatment option?

    PubMed

    Loewenbrück, Kai; Storch, Alexander

    2011-05-01

    Parkinson's disease (PD) is one of the most frequent neurodegenerative diseases and represents a major therapeutic challenge because of the so far missing therapeutic means to influence the ongoing loss of dopaminergic innervation to the striatum. Cell replacement has raised hope to offer the first restorative treatment option. Clinical trials have provided "proof of principle" that transplantation of dopamine-producing neurons into the striatum of PD patients can achieve symptomatic relief given that the striatum is sufficiently re-innervated. Various cell sources have been tested, including fetal ventral midbrain tissue, embryonic stem cells, fetal and adult neural stem cells and, after a ground-breaking discovery, induced pluripotent stem cells. Although embryonic and induced pluripotent stem cells have emerged as the most promising candidates to overcome most of the obstacles to clinical successful cell replacement, each cell source has its unique drawbacks. This review does not only provide a comprehensive overview of the different cellular candidates, including their assets and drawbacks, but also of the various additional issues that need to be addressed in order to convert cellular replacement therapies from an experimental to a clinically relevant therapeutic alternative.

  17. Neural Stem Cells Injected into the Sound-Damaged Cochlea Migrate Throughout the Cochlea and Express Markers of Hair Cells, Supporting Cells, and Spiral Ganglion Cells

    PubMed Central

    Corliss, Deborah A.; Gray, Brianna; Anderson, Julia K.; Bobbin, Richard P.; Snyder, Evan Y.; Cotanche, Douglas A.

    2007-01-01

    Most cases of hearing loss are caused by the death or dysfunction of one of the many cochlear cell types. We examined whether cells from a neural stem cell line could replace cochlear cell types lost after exposure to intense noise. For this purpose, we transplanted a clonal stem cell line into the scala tympani of sound damaged mice and guinea pigs. Utilizing morphological, protein expression and genetic criteria, stem cells were found with characteristics of both neural tissues (satellite, spiral ganglion and Schwann cells) and cells of the organ of Corti (hair cells, supporting cells). Additionally, noise-exposed, stem cell-injected animals exhibited a small but significant increase in the number of satellite cells and Type I spiral ganglion neurons compared to non-injected noise-exposed animals. These results indicate that cells of this neural stem cell line migrate from the scala tympani to Rosenthal's canal and the organ of Corti. Moreover, it suggests that cells of this neural stem cell line may derive some information needed from the microenvironment of the cochlea to differentiate into replacement cells in the cochlea. PMID:17659854

  18. Muscle Stem Cell Therapy for the Treatment of DMD Associated Cardiomyopathy

    DTIC Science & Technology

    2015-12-01

    Amelioration of hyperbilirubinemia in Gunn rats after transplantation of human induced pluripotent stem cell -derived hepatocytes. Stem Cell Reports 2015...use of differentiated pluripotent stem cells as replacement therapy in treating disease. Science 2014; 345:1247391. 12. Nishikawa T, Bell A, Brooks...Award Number: W81XWH-11-1-0803 TITLE: Muscle Stem Cell Therapy for the Treatment of DMD Associated Cardiomyopathy PRINCIPAL INVESTIGATOR

  19. Uncertain translation, uncertain benefit and uncertain risk: ethical challenges facing first-in-human trials of induced pluripotent stem (ips) cells.

    PubMed

    Fung, Ronald K F; Kerridge, Ian H

    2013-02-01

    The discovery of induced pluripotent stem (iPS) cells in 2006 was heralded as a major breakthrough in stem cell research. Since then, progress in iPS cell technology has paved the way towards clinical application, particularly cell replacement therapy, which has refueled debate on the ethics of stem cell research. However, much of the discourse has focused on questions of moral status and potentiality, overlooking the ethical issues which are introduced by the clinical testing of iPS cell replacement therapy. First-in-human trials, in particular, raise a number of ethical concerns including informed consent, subject recruitment and harm minimisation as well as the inherent uncertainty and risks which are involved in testing medical procedures on humans for the first time. These issues, while a feature of any human research, become more complex in the case of iPS cell therapy, given the seriousness of the potential risks, the unreliability of available animal models, the vulnerability of the target patient group, and the high stakes of such an intensely public area of science. Our paper will present a detailed case study of iPS cell replacement therapy for Parkinson's disease to highlight these broader ethical and epistemological concerns. If we accept that iPS cell technology is fraught with challenges which go far beyond merely refuting the potentiality of the stem cell line, we conclude that iPS cell research should not replace, but proceed alongside embryonic and adult somatic stem cell research to promote cross-fertilisation of knowledge and better clinical outcomes. © 2011 Blackwell Publishing Ltd.

  20. Engineering Replacement Tissues with Amniotic Stem Cells

    DTIC Science & Technology

    2012-10-01

    compression. J Biomech, 2010. 43(13): p. 2516-23. 17. Gadjanski, I., K. Spiller, and G. Vunjak- Novakovic , Time-dependent processes in stem cell-based...16. Gadjanski, I., K. Spiller, and G. Vunjak- Novakovic , Time-dependent processes in stem cell-based tissue engineering of articular cartilage. Stem

  1. Hematopoietic stem cells: can old cells learn new tricks?

    PubMed

    Ho, Anthony D; Punzel, Michael

    2003-05-01

    Since the establishment of cell lines derived from human embryonic stem (ES) cells, it has been speculated that out of such "raw material," we could some day produce all sorts of replacement parts for the human body. Human pluripotent stem cells can be isolated from embryonic, fetal, or adult tissues. Enormous self-renewal capacity and developmental potential are the characteristics of ES cells. Somatic stem cells, especially those derived from hematopoietic tissues, have also been reported to exhibit developmental potential heretofore not considered possible. The initial evidences for the plasticity potential of somatic stem cells were so encouraging that the opponents of ES cell research used them as arguments for restricting ES cell research. In the past months, however, critical issues have been raised challenging the validity and the interpretation of the initial data. Whereas hematopoietic stem-cell therapy has been a clinical reality for almost 40 years, there is still a long way to go in basic research before novel therapy strategies with stem cells as replacement for other organ systems can be established. Given the present status, we should keep all options open for research in ES cells and adult stem cells to appreciate the complexity of their differentiation pathways and the relative merits of various types of stem cells for regenerative medicine.

  2. Therapeutic strategies involving uterine stem cells in reproductive medicine.

    PubMed

    Simoni, Michael; Taylor, Hugh S

    2018-06-01

    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.

  3. Amniotic fluid stem cells: a promising therapeutic resource for cell-based regenerative therapy.

    PubMed

    Antonucci, Ivana; Pantalone, Andrea; Tete, Stefano; Salini, Vincenzo; Borlongan, Cesar V; Hess, David; Stuppia, Liborio

    2012-01-01

    Stem cells have been proposed as a powerful tool in the treatment of several human diseases, both for their ability to represent a source of new cells to replace those lost due to tissue injuries or degenerative diseases, and for the ability of produce trophic molecules able to minimize damage and promote recovery in the injured tissue. Different cell types, such as embryonic, fetal or adult stem cells, human fetal tissues and genetically engineered cell lines, have been tested for their ability to replace damaged cells and to restore the tissue function after transplantation. Amniotic fluid -derived Stem cells (AFS) are considered a novel resource for cell transplantation therapy, due to their high renewal capacity, the "in vitro" expression of embryonic cell lineage markers, and the ability to differentiate in tissues derived from all the three embryonic layers. Moreover, AFS do not produce teratomas when transplanted into animals and are characterized by a low antigenicity, which could represent an advantage for cell transplantation or cell replacement therapy. The present review focuses on the biological features of AFS, and on their potential use in the treatment of pathological conditions such as ischemic brain injury and bone damages.

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

    PubMed

    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.

  5. Do immunotherapy and beta cell replacement play a synergistic role in the treatment of type 1 diabetes?

    PubMed

    Li, Dong-Sheng; Warnock, Garth L; Tu, Han-Jun; Ao, Ziliang; He, Zehua; Lu, Hong; Dai, Long-Jun

    2009-10-07

    Type 1 diabetes (T1D) is the result of the autoimmune response against pancreatic insulin-producing ss-cells. Its ultimate consequence is beta-cell insufficiency-mediated dysregulation of blood glucose control. In terms of T1D treatment, immunotherapy addresses the cause of T1D, mainly through re-setting the balance between autoimmunity and regulatory mechanisms. Regulatory T cells play an important role in this immune intervention. An alternative T1D treatment is beta-cell replacement, which can reverse the consequence of the disease by replacing destroyed beta-cells in the diabetic pancreas. The applicable insulin-producing cells can be directly obtained from islet transplantation or generated from other cell sources such as autologous adult stem cells, embryonic stem cells, and induced pluripotent stem cells. In this review, we summarize the recent research progress and analyze the possible advantages and disadvantages of these two therapeutic options especially focusing on the potential synergistic effect on T1D treatment. Exploring the optimal combination of immunotherapy and beta-cell replacement will pave the way to the most effective cure for this devastating disease.

  6. Stem Cell Therapy: Repurposing Cell-Based Regenerative Medicine Beyond Cell Replacement.

    PubMed

    Napoli, Eleonora; Lippert, Trenton; Borlongan, Cesar V

    2018-02-27

    Stem cells exhibit simple and naive cellular features, yet their exact purpose for regenerative medicine continues to elude even the most elegantly designed research paradigms from developmental biology to clinical therapeutics. Based on their capacity to divide indefinitely and their dynamic differentiation into any type of tissue, the advent of transplantable stem cells has offered a potential treatment for aging-related and injury-mediated diseases. Recent laboratory evidence has demonstrated that transplanted human neural stem cells facilitate endogenous reparative mechanisms by initiating multiple regenerative processes in the brain neurogenic areas. Within these highly proliferative niches reside a myriad of potent regenerative molecules, including anti-inflammatory cytokines, proteomes, and neurotrophic factors, altogether representing a biochemical cocktail vital for restoring brain function in the aging and diseased brain. Here, we advance the concept of therapeutically repurposing stem cells not towards cell replacement per se, but rather exploiting the cells' intrinsic properties to serve as the host brain regenerative catalysts.

  7. Stem cells and their potential clinical applications in psychiatric disorders.

    PubMed

    Ratajczak, Mariusz Z; Ciechanowicz, Andrzej K; Kucharska-Mazur, Jolanta; Samochowiec, Jerzy

    2018-01-03

    The robustness of stem cells is one of the major factors that directly impacts life quality and life span. Evidence has accumulated that changes in the stem cell compartment affect human mental health and serve as an indicator of psychiatric problems. It is well known that stem cells continuously replace differentiated cells and tissues that are used up during life, although this replacement occurs at a different pace in the various organs. However, the participation of local neural stem cells in regeneration of the central nervous system is controversial. It is known that low numbers of stem cells circulate continuously in peripheral blood (PB) and lymph and undergo a circadian rhythm in their PB level, with the peak occurring early in the morning and the nadir at night, and recent evidence suggests that the number and pattern of circulating stem cells in PB changes in psychotic disorders. On the other hand, progress in the creation of induced pluripotent stem cells (iPSCs) from patient somatic cells provides valuable tools with which to study changes in gene expression in psychotic patients. We will discuss the various potential sources of stem cells that are currently employed in regenerative medicine and the mechanisms that explain some of their beneficial effects as well as the emerging problems with stem cell therapies. However, the main question remains: Will it be possible in the future to modulate the stem cell compartment to reverse psychiatric problems? Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Stem cells: science, policy, and ethics

    PubMed Central

    Fischbach, Gerald D.; Fischbach, Ruth L.

    2004-01-01

    Human embryonic stem cells offer the promise of a new regenerative medicine in which damaged adult cells can be replaced with new cells. Research is needed to determine the most viable stem cell lines and reliable ways to promote the differentiation of pluripotent stem cells into specific cell types (neurons, muscle cells, etc.). To create new cell lines, it is necessary to destroy preimplantation blastocysts. This has led to an intense debate that threatens to limit embryonic stem cell research. The profound ethical issues raised call for informed, dispassionate debate. PMID:15545983

  9. Ocular stem cells: a status update!

    PubMed Central

    2014-01-01

    Stem cells are unspecialized cells that have been a major focus of the field of regenerative medicine, opening new frontiers and regarded as the future of medicine. The ophthalmology branch of the medical sciences was the first to directly benefit from stem cells for regenerative treatment. The success stories of regenerative medicine in ophthalmology can be attributed to its accessibility, ease of follow-up and the eye being an immune-privileged organ. Cell-based therapies using stem cells from the ciliary body, iris and sclera are still in animal experimental stages but show potential for replacing degenerated photoreceptors. Limbal, corneal and conjunctival stem cells are still limited for use only for surface reconstruction, although they might have potential beyond this. Iris pigment epithelial, ciliary body epithelial and choroidal epithelial stem cells in laboratory studies have shown some promise for retinal or neural tissue replacement. Trabecular meshwork, orbital and sclera stem cells have properties identical to cells of mesenchymal origin but their potential has yet to be experimentally determined and validated. Retinal and retinal pigment epithelium stem cells remain the most sought out stem cells for curing retinal degenerative disorders, although treatments using them have resulted in variable outcomes. The functional aspects of the therapeutic application of lenticular stem cells are not known and need further attention. Recently, embryonic stem cell-derived retinal pigment epithelium has been used for treating patients with Stargardts disease and age-related macular degeneration. Overall, the different stem cells residing in different components of the eye have shown some success in clinical and animal studies in the field of regenerative medicine. PMID:25158127

  10. Stem cell recruitment of newly formed host cells via a successful seduction? Filling the gap between neurogenic niche and injured brain site.

    PubMed

    Tajiri, Naoki; Kaneko, Yuji; Shinozuka, Kazutaka; Ishikawa, Hiroto; Yankee, Ernest; McGrogan, Michael; Case, Casey; Borlongan, Cesar V

    2013-01-01

    Here, we report that a unique mechanism of action exerted by stem cells in the repair of the traumatically injured brain involves their ability to harness a biobridge between neurogenic niche and injured brain site. This biobridge, visualized immunohistochemically and laser captured, corresponded to an area between the neurogenic subventricular zone and the injured cortex. That the biobridge expressed high levels of extracellular matrix metalloproteinases characterized initially by a stream of transplanted stem cells, but subsequently contained only few to non-detectable grafts and overgrown by newly formed host cells, implicates a novel property of stem cells. The transplanted stem cells manifest themselves as pathways for trafficking the migration of host neurogenic cells, but once this biobridge is formed between the neurogenic site and the injured brain site, the grafted cells disappear and relinquish their task to the host neurogenic cells. Our findings reveal that long-distance migration of host cells from the neurogenic niche to the injured brain site can be achieved through transplanted stem cells serving as biobridges for initiation of endogenous repair mechanisms. This is the first report of a stem cell-paved "biobridge". Indeed, to date the two major schools of discipline in stem cell repair mechanism primarily support the concept of "cell replacement" and bystander effects of "trophic factor secretion". The present novel observations of a stem cell seducing a host cell to engage in brain repair advances basic science concepts on stem cell biology and extracellular matrix, as well as provokes translational research on propagating this stem cell-paved biobridge beyond cell replacement and trophic factor secretion for the treatment of traumatic brain injury and other neurological disorders.

  11. Novel clinical uses for cord blood derived mesenchymal stromal cells.

    PubMed

    Olson, Amanda L; McNiece, Ian K

    2015-06-01

    Regenerative medicine offers new hope for many debilitating diseases that result in damage to tissues and organs. The concept is straightforward with replacement of damaged cells with new functional cells. However, most tissues and organs are complex structures involving multiple cell types, supportive structures, a microenvironment producing cytokines and growth factors and a vascular system to supply oxygen and other nutrients. Therefore repair, particularly in the setting of ischemic damage, may require delivery of multiple cell types providing new vessel formation, a new microenvironment and functional cells. The field of stem cell biology has identified a number of stem cell sources including embryonic stem cells and adult stem cells that offer the potential to replace virtually all functional cells of the body. The focus of this article is a discussion of the potential of mesenchymal stromal cells (MSCs) from cord blood (CB) for regenerative medicine approaches. Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  12. Implications of Parkinson's disease pathophysiology for the development of cell replacement strategies and drug discovery in neurodegenerative diseases.

    PubMed

    Pan-Montojo, Francisco; Funk, Richard H W

    2012-11-01

    Parkinson's disease (PD) is a progressive neurodegenerative disorder traditionally characterized by the loss of dopaminergic neurons in the substantia nigra (SN) at the midbrain. The potential use of adult or embryonic stem cells, induced pluriputent stem (iPS) cells and endogenous neurogenesis in cell replacement strategies has lead to numerous studies and clinical trials in this direction. It is now possible to differentiate stem cells into dopaminergic neurons in vitro and clinical trials have shown an improvement in PD-related symptoms after intra-striatal embryonic transplants and acceptable cell survival rates on the mid term. However, clinical improvement is transitory and associated with a strong placebo effect. Interestingly, recent pathological studies in PD patients who received embryonic stem cells show that in PD patients, grafted neurons show PD-related pathology. In this manuscript we review the latest findings regarding PD pathophysiology and give an outlook on the implications of these findings in how cell replacement strategies for PD treatment should be tested. These include changes in the type of animal models used, the preparation/conditioning of the cells before intracerebral injection, specially regarding backbone chronic diseases in iPS cells and determining the optimal proliferation, survival, differentiation and migration capacity of the grafted cells.

  13. Prospects for Replacement of Auditory Neurons by Stem Cells

    PubMed Central

    Shi, Fuxin; Edge, Albert S.B.

    2013-01-01

    Sensorineural hearing loss is caused by degeneration of hair cells or auditory neurons. Spiral ganglion cells, the primary afferent neurons of the auditory system, are patterned during development and send out projections to hair cells and to the brainstem under the control of largely unknown guidance molecules. The neurons do not regenerate after loss and even damage to their projections tends to be permanent. The genesis of spiral ganglion neurons and their synapses forms a basis for regenerative approaches. In this review we critically present the current experimental findings on auditory neuron replacement. We discuss the latest advances with a focus on (a) exogenous stem cell transplantation into the cochlea for neural replacement, (b) expression of local guidance signals in the cochlea after loss of auditory neurons, (c) the possibility of neural replacement from an endogenous cell source, and (d) functional changes from cell engraftment. PMID:23370457

  14. Stem Cells News Update: A Personal Perspective

    PubMed Central

    Wong, SC

    2013-01-01

    This article is a follow-up to a previous Commentary published in 2011. It updates some of the events mentioned in that Commentary and continues with more interesting and exciting news on stem cell research and the emerging field of Regenerative Medicine. Some of the news includes: 1) the 2012 Nobel Prize for Medicine awarded to John B. Gurdon and Shinya Yamanaka; 2) the cloning of human embryonic stem cells; 3) the continued search for truly pluripotent adult stem cells via in vitro and in vivo protocols; 4) the breakthrough in organ replacements; 5) the global stem cell race; 6) the global stem cell cryo-preservation business; 7) the worldwide stem cell donor registries, and 8) the issue of government regulation on stem cell therapy. PMID:24778557

  15. Stem cells news update: a personal perspective.

    PubMed

    Wong, Sc

    2013-12-01

    This article is a follow-up to a previous Commentary published in 2011. It updates some of the events mentioned in that Commentary and continues with more interesting and exciting news on stem cell research and the emerging field of Regenerative Medicine. Some of the news includes: 1) the 2012 Nobel Prize for Medicine awarded to John B. Gurdon and Shinya Yamanaka; 2) the cloning of human embryonic stem cells; 3) the continued search for truly pluripotent adult stem cells via in vitro and in vivo protocols; 4) the breakthrough in organ replacements; 5) the global stem cell race; 6) the global stem cell cryo-preservation business; 7) the worldwide stem cell donor registries, and 8) the issue of government regulation on stem cell therapy.

  16. Characterization of human pancreatic progenitor cells.

    PubMed

    Noguchi, Hirofumi; Naziruddin, Bashoo; Jackson, Andrew; Shimoda, Masayuki; Ikemoto, Tetsuya; Fujita, Yasutaka; Chujo, Daisuke; Takita, Morihito; Kobayashi, Naoya; Onaca, Nicholas; Hayashi, Shuji; Levy, Marlon F; Matsumoto, Shinichi

    2010-01-01

    β-Cell replacement therapy via islet transplantation is an effective treatment for diabetes mellitus, but its widespread use is severely limited by the shortage of donor organs. Because pancreatic stem/progenitor cells are abundantly available in the pancreas of these patients and in donor organs, the cells could become a useful target for β-cell replacement therapy. We previously established a mouse pancreatic stem cell line without genetic manipulation. In this study, we used the techniques to identify and isolate human pancreatic stem/progenitor cells. The cells from a duct-rich population were cultured in 23 kinds of culture media, based on media for mouse pancreatic stem cells or for human embryonic stem cells. The cells in serum-free media formed "cobblestone" morphologies, similar to a mouse pancreatic stem cell line. On the other hand, the cells in serum-containing medium and the medium for human embryonic stem cells formed "fibroblast-like" morphologies. The cells divided actively until day 30, and the population doubling level (PDL) was 6-10. However, the cells stopped dividing after 30 days in any culture conditions. During the cultures, the nucleus/cytoplasm (N/C) ratio decreased, suggesting that the cells entered senescence. Exendin-4 treatment and transduction of PDX-1 and NeuroD proteins by protein transduction technology into the cells induced insulin and pancreas-related gene expression. Although the duplications of these cells were limited, this approach could provide a potential new source of insulin-producing cells for transplantation.

  17. The use of stem cells in regenerative medicine for Parkinson's and Huntington's Diseases.

    PubMed

    Lescaudron, L; Naveilhan, P; Neveu, I

    2012-01-01

    Cell transplantation has been proposed as a means of replacing specific cell populations lost through neurodegenerative processes such as that seen in Parkinson's or Huntington's diseases. Improvement of the clinical symptoms has been observed in a number of Parkinson and Huntington's patients transplanted with freshly isolated fetal brain tissue but such restorative approach is greatly hampered by logistic and ethical concerns relative to the use of fetal tissue, in addition to potential side effects that remain to be controlled. In this context, stem cells that are capable of self-renewal and can differentiate into neurons, have received a great deal of interest, as demonstrated by the numerous studies based on the transplantation of neural stem/progenitor cells, embryonic stem cells or mesenchymal stem cells into animal models of Parkinson's or Huntington's diseases. More recently, the induction of pluripotent stem cells from somatic adult cells has raised a new hope for the treatment of neurodegenerative diseases. In the present article, we review the main experimental approaches to assess the efficiency of cell-based therapy for Parkinson's or Huntington's diseases, and discuss the recent advances in using stem cells to replace lost dopaminergic mesencephalic or striatal neurons. Characteristics of the different stem cells are extensively examined with a special attention to their ability of producing neurotrophic or immunosuppressive factors, as these may provide a favourable environment for brain tissue repair and long-term survival of transplanted cells in the central nervous system. Thus, stem cell therapy can be a valuable tool in regenerative medicine.

  18. Application of stem cell/growth factor system, as a multimodal therapy approach in regenerative medicine to improve cell therapy yields.

    PubMed

    Pourrajab, Fatemeh; Babaei Zarch, Mojtaba; Baghi Yazdi, Mohammad; Rahimi Zarchi, Abolfazl; Vakili Zarch, Abbas

    2014-04-15

    Stem cells hold a great promise for regenerative medicine, especially for replacing cells in infarcted organ that hardly have any intrinsic renewal capacity, including heart and brain. Signaling pathways that regulate pluripotency or lineage-specific gene and protein expression have been the major focus of stem cell research. Between them, there are some well known signaling pathways such as GF/GFR systems, SDF-1α/CXC4 ligand receptor interaction and PI3K/Akt signaling, and cytokines may regulate cell fate decisions, and can be utilized to positively influence cell therapy outcomes or accentuate synergistic compliance. For example, contributing factors in the progression of heart failure are both the loss of cardiomyocytes after myocardial infarction, and the absence of an adequate endogenous repair signaling. Combining cell engraftment with therapeutic signaling factor delivery is more exciting in terms of host progenitor/donor stem cell survival and proliferation. Thus stem cell-based therapy, besides triggering signaling pathways through GF/GFR systems can become a realistic option in regenerative processes for replacing lost cells and reconstituting the damaged organ, as before. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. Comment on "A new method for treating fecal incontinence by implanting stem cells derived from human adipose tissue: preliminary findings of a randomized double-blind clinical trial".

    PubMed

    El-Said, Mohammed Mohammed; Emile, Sameh Hany

    2018-04-25

    In the study by Sarveazad et al. adipose tissue-derived stem cells were injected to reinforce anal sphincter repair. The authors came to the conclusion that injection of stem cells during repair surgery for fecal incontinence may cause replacement of fibrous tissue, which may be a key point in treatment of fecal incontinence. The authors emphasized in their "Discussion" section that the ability of stem cells to differentiate into muscle fibers, replacing the fibrous tissue at the site of repair, is their main action, which may not be accurate. We think that healing of repaired anal sphincter begins with granulation tissue formation, which then matures into fibrous tissue that becomes infiltrated by muscle fibers from the approximated cut ends of the sphincter, resulting in regain of sphincter muscle continuity. This is supported by many experimental studies that have evaluated local injection of stem cells during sphincteroplasty in rats and shown that the injected stem cells do not differentiate into muscle fibers but may induce healing by a strong fibrous tissue. Further studies are needed to determine the main mechanism of action of mesenchymal stems cells in augmenting anal sphincter repair.

  20. Recent Advances towards the Clinical Application of Stem Cells for Retinal Regeneration

    PubMed Central

    Becker, Silke; Jayaram, Hari; Limb, G. Astrid

    2012-01-01

    Retinal degenerative diseases constitute a major cause of irreversible blindness in the world. Stem cell-based therapies offer hope for these patients at risk of or suffering from blindness due to the deterioration of the neural retina. Various sources of stem cells are currently being investigated, ranging from human embryonic stem cells to adult-derived induced pluripotent stem cells as well as human Müller stem cells, with the first clinical trials to investigate the safety and tolerability of human embryonic stem cell-derived retinal pigment epithelium cells having recently commenced. This review aims to summarize the latest advances in the development of stem cell strategies for the replacement of retinal neurons and their supportive cells, the retinal pigment epithelium (RPE) affected by retinal degenerative conditions. Particular emphasis will be given to the advances in stem cell transplantation and the challenges associated with their translation into clinical practice. PMID:24710533

  1. Limbal Stem Cell Preservation During Proton Beam Irradiation for Diffuse Iris Melanoma.

    PubMed

    Singh, Arun D; Dupps, William J; Biscotti, Charles V; Suh, John H; Lathrop, Kira L; Nairn, John P; Shih, Helen

    2017-01-01

    To report the outcome after limbal stem cell preservation during proton beam irradiation for diffuse iris melanoma. This is a single-case report of diffuse iris melanoma that was managed with proton beam radiation (53 Gy), wherein preemptively harvested superior and inferior limbal stem cells before radiation were replaced after irradiation. Regeneration of the palisades of Vogt and the limbal stem cells was documented by an optical coherence tomography-based imaging protocol. At 24 months after radiation therapy, best-corrected visual acuity was 20/25. The cornea was clear without evidence of limbal stem cell dysfunction. Clinical examination (including gonioscopy and ultrasound biomicroscopy [UBM]) was indicative of local control, and systemic surveillance was negative for metastatic disease. At posttransplant (21 months), there were more palisade structures visible in both anterior and posterior regions of the superior and inferior limbus, and the linear presentation of the inferior palisades appears to have regenerated. Diffuse iris melanoma can be managed successfully with proton beam radiation while preserving corneal limbal stem cells by harvesting them before radiation and then replacing them after irradiation. Regeneration of the palisades of Vogt could be documented by an optical coherence tomography-based imaging protocol.

  2. Potential of Induced Pluripotent Stem Cells (iPSCs) for Treating Age-Related Macular Degeneration (AMD).

    PubMed

    Fields, Mark; Cai, Hui; Gong, Jie; Del Priore, Lucian

    2016-12-08

    The field of stem cell biology has rapidly evolved in the last few decades. In the area of regenerative medicine, clinical applications using stem cells hold the potential to be a powerful tool in the treatment of a wide variety of diseases, in particular, disorders of the eye. Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) are promising technologies that can potentially provide an unlimited source of cells for cell replacement therapy in the treatment of retinal degenerative disorders such as age-related macular degeneration (AMD), Stargardt disease, and other disorders. ESCs and iPSCs have been used to generate retinal pigment epithelium (RPE) cells and their functional behavior has been tested in vitro and in vivo in animal models. Additionally, iPSC-derived RPE cells provide an autologous source of cells for therapeutic use, as well as allow for novel approaches in disease modeling and drug development platforms. Clinical trials are currently testing the safety and efficacy of these cells in patients with AMD. In this review, the current status of iPSC disease modeling of AMD is discussed, as well as the challenges and potential of this technology as a viable option for cell replacement therapy in retinal degeneration.

  3. Liver fibrosis alleviation after co-transplantation of hematopoietic stem cells with mesenchymal stem cells in patients with thalassemia major.

    PubMed

    Ghavamzadeh, Ardeshir; Sotoudeh, Masoud; Hashemi Taheri, Amir Pejman; Alimoghaddam, Kamran; Pashaiefar, Hossein; Jalili, Mahdi; Shahi, Farhad; Jahani, Mohammad; Yaghmaie, Marjan

    2018-02-01

    The aims of this study are to determine the replacement rate of damaged hepatocytes by donor-derived cells in sex-mismatched recipient patients with thalassemia major and to determine whether co-transplantation of mesenchymal stem cells and hematopoietic stem cells (HSCs) can alleviate liver fibrosis. Ten sex-mismatched donor-recipient pairs who received co-transplantation of HSCs with mesenchymal stem cells were included in our study. Liver biopsy was performed before transplantation. Two other liver biopsies were performed between 2 and 5 years after transplantation. The specimens were studied for the presence of donor-derived epithelial cells or hepatocytes using fluorescence in situ hybridization by X- and Y-centromeric probes and immunohistochemical staining for pancytokeratin, CD45, and a hepatocyte-specific antigen. All sex-mismatched tissue samples demonstrated donor-derived hepatocyte independent of donor gender. XY-positive epithelial cells or hepatocytes accounted for 11 to 25% of the cells in histologic sections of female recipients in the first follow-up. It rose to 47-95% in the second follow-up. Although not statistically significant, four out of ten patients showed signs of improvement in liver fibrosis. Our results showed that co-transplantation of HSC with mesenchymal stem cells increases the rate of replacement of recipient hepatocytes by donor-derived cells and may improve liver fibrosis.

  4. Generation of hematopoietic stem cells from human embryonic stem cells using a defined, stepwise, serum-free, and serum replacement-free monolayer culture method.

    PubMed

    Kim, So-Jung; Jung, Ji-Won; Ha, Hye-Yeong; Koo, Soo Kyung; Kim, Eung-Gook; Kim, Jung-Hyun

    2017-03-01

    Embryonic stem cells (ESCs) can be expanded infinitely in vitro and have the potential to differentiate into hematopoietic stem cells (HSCs); thus, they are considered a useful source of cells for HSC production. Although several technical in vitro methods for engineering HSCs from pluripotent stem cells have been developed, clinical application of HSCs engineered from pluripotent stem cells is restricted because of the possibility of xenogeneic contamination resulting from the use of murine materials. Human ESCs (CHA-hES15) were cultured on growth factor-reduced Matrigel-coated dishes in the mTeSR1 serum-free medium. When the cells were 70% confluent, we initiated HSC differentiation by three methods involving (1) knockout serum replacement (KSR), cytokines, TGFb1, EPO, and FLT3L; (2) KSR, cytokines, and bFGF; or (3) cytokines and bFGF. Among the three differentiation methods, the minimal number of cytokines without KSR resulted in the greatest production of HSCs. The optimized method resulted in a higher proportion of CD34 + CD43 + hematopoietic progenitor cells (HPCs) and CD34 + CD45 + HPCs compared to the other methods. In addition, the HSCs showed the potential to differentiate into multiple lineages of hematopoietic cells in vitro . In this study, we optimized a two-step, serum-free, animal protein-free, KSR-free, feeder-free, chemically defined monolayer culture method for generation of HSCs and hematopoietic stem and progenitor cells (HSPCs) from human ESCs.

  5. Effect of Antioxidants and Apoptosis Inhibitors on Cryopreservation of Murine Germ Cells Enriched for Spermatogonial Stem Cells.

    PubMed

    Ha, Seung-Jung; Kim, Byung-Gak; Lee, Yong-An; Kim, Yong-Hee; Kim, Bang-Jin; Jung, Sang-Eun; Pang, Myeong-Geol; Ryu, Buom-Yong

    2016-01-01

    Spermatogonial stem cells (SSCs) are germline stem cells that serve as the foundation of spermatogenesis to maintain fertility throughout a male's lifetime. To treat male infertility using stem cell banking systems and transplantation, it is important to be able to preserve SSCs for long periods of time. Therefore, this study was conducted to develop an optimal cryopreservation protocol for SSCs using antioxidants and apoptosis inhibitors in freezing medium. No differences were observed compared to controls when SSCs were cryopreserved in the presence of apoptosis inhibitors by themselves. However, mouse germ cells cryopreserved in basal medium containing the antioxidant hypotaurine (14 mM) resulted in significantly greater proliferation potential and mitochondrial activity. Furthermore, treatment groups with combinations containing 200 mM trehalose and 14 mM hypotaurine showed higher proliferation rates compared to controls. In addition, several serum free conditions were evaluated for SSC cryopreservation. Treatment media containing 10% or 20% knockout serum replacement resulted in similar cryopreservation results compared to media containing FBS. SSC transplantation was also performed to confirm the functionality of SSCs frozen in 14 mM hypotaurine. Donor SSCs formed normal spermatogenic colonies and sperm in the recipient testis. These data indicate that inclusion of 14 mM hypotaurine in cryopreservation media is an effective way to efficiently cryopreserve germ cells enriched for SSCs and that knockout serum replacement can replace FBS in germ cell cryopreservation media.

  6. The clinical use of regenerative therapy in COPD

    PubMed Central

    Lipsi, Roberto; Rogliani, Paola; Calzetta, Luigino; Segreti, Andrea; Cazzola, Mario

    2014-01-01

    Regenerative or stem cell therapy is an emerging field of treatment based on stimulation of endogenous resident stem cells or administration of exogenous stem cells to treat diseases or injury and to replace malfunctioning or damaged tissues. Current evidence suggests that in the lung, these cells may participate in tissue homeostasis and regeneration after injury. Animal and human studies have demonstrated that tissue-specific stem cells and bone marrow-derived cells contribute to lung tissue regeneration and protection, and thus administration of exogenous stem/progenitor cells or humoral factors responsible for the activation of endogenous stem/progenitor cells may be a potent next-generation therapy for chronic obstructive pulmonary disease. The use of bone marrow-derived stem cells could allow repairing and regenerate the damaged tissue present in chronic obstructive pulmonary disease by means of their engraftment into the lung. Another approach could be the stimulation of resident stem cells by means of humoral factors or photobiostimulation. PMID:25548520

  7. Pluripotent Stem Cells for Retinal Tissue Engineering: Current Status and Future Prospects.

    PubMed

    Singh, Ratnesh; Cuzzani, Oscar; Binette, François; Sternberg, Hal; West, Michael D; Nasonkin, Igor O

    2018-04-19

    The retina is a very fine and layered neural tissue, which vitally depends on the preservation of cells, structure, connectivity and vasculature to maintain vision. There is an urgent need to find technical and biological solutions to major challenges associated with functional replacement of retinal cells. The major unmet challenges include generating sufficient numbers of specific cell types, achieving functional integration of transplanted cells, especially photoreceptors, and surgical delivery of retinal cells or tissue without triggering immune responses, inflammation and/or remodeling. The advances of regenerative medicine enabled generation of three-dimensional tissues (organoids), partially recreating the anatomical structure, biological complexity and physiology of several tissues, which are important targets for stem cell replacement therapies. Derivation of retinal tissue in a dish creates new opportunities for cell replacement therapies of blindness and addresses the need to preserve retinal architecture to restore vision. Retinal cell therapies aimed at preserving and improving vision have achieved many improvements in the past ten years. Retinal organoid technologies provide a number of solutions to technical and biological challenges associated with functional replacement of retinal cells to achieve long-term vision restoration. Our review summarizes the progress in cell therapies of retina, with focus on human pluripotent stem cell-derived retinal tissue, and critically evaluates the potential of retinal organoid approaches to solve a major unmet clinical need-retinal repair and vision restoration in conditions caused by retinal degeneration and traumatic ocular injuries. We also analyze obstacles in commercialization of retinal organoid technology for clinical application.

  8. Stem cells with potential to generate insulin producing cells in man.

    PubMed

    Zulewski, Henryk

    2006-10-14

    Replacement of insulin-producing cells represents an almost ideal treatment for patients with diabetes mellitus type 1. Transplantation of pancreatic islets of Langerhans--although successful in experienced centres--is limited by the lack of donor organs. Generation of insulin-producing cells from stem cells represents an attractive alternative. Stem cells with the potential to differentiate into insulin-producing cells include embryonic stem cells (ESC) as well as adult stem cells from various tissues including the pancreas, liver, central nervous system, bone marrow and adipose tissue. The use of human ESC is hampered by ethical concerns and the inability to create patient specific ESC with therapeutic cloning. Among adult stem cells mesenchymal stem cells appear to have a particular developmental plasticity ex vivo that include their ability to adopt a pancreatic endocrine phenotype. The present review summarises the current knowledge on the development of insulin-producing cells from stem cells with special emphasis on human mesenchymal stem cells isolated from the pancreas and adipose tissue.

  9. Stem cells with potential to generate insulin-producing cells in man.

    PubMed

    Zulewski, Henryk

    2007-03-02

    Replacement of insulin-producing cells represents an almost ideal treatment for patients with diabetes mellitus type 1. Transplantation of pancreatic islets of Langerhans--although successful in experienced centres--is limited by the lack of donor organs. Generation of insulin-producing cells from stem cells represents an attractive alternative. Stem cells with the potential to differentiate into insulin-producing cells include embryonic stem cells (ESC) as well as adult stem cells from various tissues including the pancreas, liver, central nervous system, bone marrow and adipose tissue. The use of human ESC is hampered by ethical concerns and the inability to create patient specific ESC with therapeutic cloning. Among adult stem cells mesenchymal stem cells appear to have a particular developmental plasticity ex vivo that include their ability to adopt a pancreatic endocrine phenotype. The present review summarises the current knowledge on the development of insulin-producing cells from stem cells with special emphasis on human mesenchymal stem cells isolated from the pancreas and adipose tissue.

  10. Directed induction of functional motor neuron-like cells from genetically engineered human mesenchymal stem cells.

    PubMed

    Park, Hwan-Woo; Cho, Jung-Sun; Park, Chul-Kyu; Jung, Sung Jun; Park, Chang-Hwan; Lee, Shin-Jae; Oh, Seog Bae; Park, Young-Seok; Chang, Mi-Sook

    2012-01-01

    Cell replacement using stem cells is a promising therapeutic approach to treat degenerative motor neuron (MN) disorders, such as amyotrophic lateral sclerosis and spinal cord injury. Human bone marrow-derived mesenchymal stem cells (hMSCs) are a desirable cell source for autologous cell replacement therapy to treat nervous system injury due to their plasticity, low immunogenicity, and a lower risk of tumor formation than embryonic stem cells. However, hMSCs are inefficient with regards to differentiating into MN-like cells. To solve this limitation, we genetically engineered hMSCs to express MN-associated transcription factors, Olig2 and Hb9, and then treat the hMSCs expressing Olig2 and Hb9 with optimal MN induction medium (MNIM). This method of induction led to higher expression (>30% of total cells) of MN markers. Electrophysiological data revealed that the induced hMSCs had the excitable properties of neurons and were able to form functional connections with muscle fibers in vitro. Furthermore, when the induced hMSCs were transplanted into an injured organotypic rat spinal cord slice culture, an ex vivo model of spinal cord injury, they exhibited characteristics of MNs. The data strongly suggest that induced Olig2/Hb9-expressing hMSCs were clearly reprogrammed and directed toward a MN-like lineage. We propose that methods to induce Olig2 and Hb9, followed by further induction with MNIM have therapeutic potential for autologous cell replacement therapy to treat degenerative MN disorders.

  11. [Breakthrough in research on pluripotent stem cells and their application in medicine].

    PubMed

    Valdimarsdóttir, Guðrún; Richter, Anne

    2015-12-01

    Embryonic stem cells are, as the name indicates, isolated from embryos. They are pluripotent cells which can be maintained undifferentiated or induced to differentiate into any cell type of the body. In 1998 the first isolation of human embryonic stem cells was successful and they became an interesting source for stem cell regenerative medicine. Only 8 years later pluripotent stem cells were generated by reprogramming somatic cells into induced pluripotent stem cells (iPSCs). This was a revolution in the way people thought of cell commitment during development. Since then, a lot of research has been done in understanding the molecular biology of pluripotent stem cells. iPSCs can be generated from somatic cells of a patient and therefore have the same genome. Hence, iPSCs have great potential application in medicine, as they can be utilized in disease modelling, drug screening and cell replacement therapy.

  12. Engineered Biomaterials to Enhance Stem Cell-Based Cardiac Tissue Engineering and Therapy.

    PubMed

    Hasan, Anwarul; Waters, Renae; Roula, Boustany; Dana, Rahbani; Yara, Seif; Alexandre, Toubia; Paul, Arghya

    2016-07-01

    Cardiovascular disease is a leading cause of death worldwide. Since adult cardiac cells are limited in their proliferation, cardiac tissue with dead or damaged cardiac cells downstream of the occluded vessel does not regenerate after myocardial infarction. The cardiac tissue is then replaced with nonfunctional fibrotic scar tissue rather than new cardiac cells, which leaves the heart weak. The limited proliferation ability of host cardiac cells has motivated investigators to research the potential cardiac regenerative ability of stem cells. Considerable progress has been made in this endeavor. However, the optimum type of stem cells along with the most suitable matrix-material and cellular microenvironmental cues are yet to be identified or agreed upon. This review presents an overview of various types of biofunctional materials and biomaterial matrices, which in combination with stem cells, have shown promises for cardiac tissue replacement and reinforcement. Engineered biomaterials also have applications in cardiac tissue engineering, in which tissue constructs are developed in vitro by combining stem cells and biomaterial scaffolds for drug screening or eventual implantation. This review highlights the benefits of using biomaterials in conjunction with stem cells to repair damaged myocardium and give a brief description of the properties of these biomaterials that make them such valuable tools to the field. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Stem cell-based biological tooth repair and regeneration

    PubMed Central

    Volponi, Ana Angelova; Pang, Yvonne; Sharpe, Paul T.

    2010-01-01

    Teeth exhibit limited repair in response to damage, and dental pulp stem cells probably provide a source of cells to replace those damaged and to facilitate repair. Stem cells in other parts of the tooth, such as the periodontal ligament and growing roots, play more dynamic roles in tooth function and development. Dental stem cells can be obtained with ease, making them an attractive source of autologous stem cells for use in restoring vital pulp tissue removed because of infection, in regeneration of periodontal ligament lost in periodontal disease, and for generation of complete or partial tooth structures to form biological implants. As dental stem cells share properties with mesenchymal stem cells, there is also considerable interest in their wider potential to treat disorders involving mesenchymal (or indeed non-mesenchymal) cell derivatives, such as in Parkinson's disease. PMID:21035344

  14. Crispr-mediated Gene Targeting of Human Induced Pluripotent Stem Cells.

    PubMed

    Byrne, Susan M; Church, George M

    2015-01-01

    CRISPR/Cas9 nuclease systems can create double-stranded DNA breaks at specific sequences to efficiently and precisely disrupt, excise, mutate, insert, or replace genes. However, human embryonic stem or induced pluripotent stem cells (iPSCs) are more difficult to transfect and less resilient to DNA damage than immortalized tumor cell lines. Here, we describe an optimized protocol for genome engineering of human iPSCs using a simple transient transfection of plasmids and/or single-stranded oligonucleotides. With this protocol, we achieve transfection efficiencies greater than 60%, with gene disruption efficiencies from 1-25% and gene insertion/replacement efficiencies from 0.5-10% without any further selection or enrichment steps. We also describe how to design and assess optimal sgRNA target sites and donor targeting vectors; cloning individual iPSC by single cell FACS sorting, and genotyping successfully edited cells.

  15. Multidimensional nanomaterials for the control of stem cell fate

    NASA Astrophysics Data System (ADS)

    Chueng, Sy-Tsong Dean; Yang, Letao; Zhang, Yixiao; Lee, Ki-Bum

    2016-09-01

    Current stem cell therapy suffers low efficiency in giving rise to differentiated cell lineages, which can replace the original damaged cells. Nanomaterials, on the other hand, provide unique physical size, surface chemistry, conductivity, and topographical microenvironment to regulate stem cell differentiation through multidimensional approaches to facilitate gene delivery, cell-cell, and cell-ECM interactions. In this review, nanomaterials are demonstrated to work both alone and synergistically to guide selective stem cell differentiation. From three different nanotechnology families, three approaches are shown: (1) soluble microenvironmental factors; (2) insoluble physical microenvironment; and (3) nano-topographical features. As regenerative medicine is heavily invested in effective stem cell therapy, this review is inspired to generate discussions in the potential clinical applications of multi-dimensional nanomaterials.

  16. Assessment of Safety and Functional Efficacy of Stem Cell-Based Therapeutic Approaches Using Retinal Degenerative Animal Models

    PubMed Central

    Lin, Tai-Chi; Zhu, Danhong; Hinton, David R.; Clegg, Dennis O.; Humayun, Mark S.

    2017-01-01

    Dysfunction and death of retinal pigment epithelium (RPE) and or photoreceptors can lead to irreversible vision loss. The eye represents an ideal microenvironment for stem cell-based therapy. It is considered an “immune privileged” site, and the number of cells needed for therapy is relatively low for the area of focused vision (macula). Further, surgical placement of stem cell-derived grafts (RPE, retinal progenitors, and photoreceptor precursors) into the vitreous cavity or subretinal space has been well established. For preclinical tests, assessments of stem cell-derived graft survival and functionality are conducted in animal models by various noninvasive approaches and imaging modalities. In vivo experiments conducted in animal models based on replacing photoreceptors and/or RPE cells have shown survival and functionality of the transplanted cells, rescue of the host retina, and improvement of visual function. Based on the positive results obtained from these animal experiments, human clinical trials are being initiated. Despite such progress in stem cell research, ethical, regulatory, safety, and technical difficulties still remain a challenge for the transformation of this technique into a standard clinical approach. In this review, the current status of preclinical safety and efficacy studies for retinal cell replacement therapies conducted in animal models will be discussed. PMID:28928775

  17. Therapeutic potential of dental stem cells

    PubMed Central

    Chalisserry, Elna Paul; Nam, Seung Yun; Park, Sang Hyug; Anil, Sukumaran

    2017-01-01

    Stem cell biology has become an important field in regenerative medicine and tissue engineering therapy since the discovery and characterization of mesenchymal stem cells. Stem cell populations have also been isolated from human dental tissues, including dental pulp stem cells, stem cells from human exfoliated deciduous teeth, stem cells from apical papilla, dental follicle progenitor cells, and periodontal ligament stem cells. Dental stem cells are relatively easily obtainable and exhibit high plasticity and multipotential capabilities. The dental stem cells represent a gold standard for neural-crest-derived bone reconstruction in humans and can be used for the repair of body defects in low-risk autologous therapeutic strategies. The bioengineering technologies developed for tooth regeneration will make substantial contributions to understand the developmental process and will encourage future organ replacement by regenerative therapies in a wide variety of organs such as the liver, kidney, and heart. The concept of developing tooth banking and preservation of dental stem cells is promising. Further research in the area has the potential to herald a new dawn in effective treatment of notoriously difficult diseases which could prove highly beneficial to mankind in the long run. PMID:28616151

  18. I-SceI-mediated double-strand break does not increase the frequency of homologous recombination at the Dct locus in mouse embryonic stem cells.

    PubMed

    Fenina, Myriam; Simon-Chazottes, Dominique; Vandormael-Pournin, Sandrine; Soueid, Jihane; Langa, Francina; Cohen-Tannoudji, Michel; Bernard, Bruno A; Panthier, Jean-Jacques

    2012-01-01

    Targeted induction of double-strand breaks (DSBs) at natural endogenous loci was shown to increase the rate of gene replacement by homologous recombination in mouse embryonic stem cells. The gene encoding dopachrome tautomerase (Dct) is specifically expressed in melanocytes and their precursors. To construct a genetic tool allowing the replacement of Dct gene by any gene of interest, we generated an embryonic stem cell line carrying the recognition site for the yeast I-SceI meganuclease embedded in the Dct genomic segment. The embryonic stem cell line was electroporated with an I-SceI expression plasmid, and a template for the DSB-repair process that carried sequence homologies to the Dct target. The I-SceI meganuclease was indeed able to introduce a DSB at the Dct locus in live embryonic stem cells. However, the level of gene targeting was not improved by the DSB induction, indicating a limited capacity of I-SceI to mediate homologous recombination at the Dct locus. These data suggest that homologous recombination by meganuclease-induced DSB may be locus dependent in mammalian cells.

  19. Applications of Raman micro-spectroscopy to stem cell technology: label-free molecular discrimination and monitoring cell differentiation.

    PubMed

    Ghita, Adrian; Pascut, Flavius C; Sottile, Virginie; Denning, Chris; Notingher, Ioan

    Stem cell therapy is widely acknowledged as a key medical technology of the 21st century which may provide treatments for many currently incurable diseases. These cells have an enormous potential for cell replacement therapies to cure diseases such as Parkinson's disease, diabetes and cardiovascular disorders, as well as in tissue engineering as a reliable cell source for providing grafts to replace and repair diseased tissues. Nevertheless, the progress in this field has been difficult in part because of lack of techniques that can measure non-invasively the molecular properties of cells. Such repeated measurements can be used to evaluate the culture conditions during differentiation, cell quality and phenotype heterogeneity of stem cell progeny. Raman spectroscopy is an optical technique based on inelastic scattering of laser photons by molecular vibrations of cellular molecules and can be used to provide chemical fingerprints of cells or organelles without fixation, lysis or use of labels and other contrast enhancing chemicals. Because differentiated cells are specialized to perform specific functions, these cells produce specific biochemicals that can be detected by Raman micro-spectroscopy. This mini-review paper describes applications of Raman micro-scpectroscopy to measure moleculare properties of stem cells during differentiation in-vitro. The paper focuses on time- and spatially-resolved Raman spectral measurements that allow repeated investigation of live stem cells in-vitro.

  20. Induced Pluripotent Stem Cells: Generation, Characterization, and Differentiation--Methods and Protocols.

    PubMed

    Graversen, Veronica Kon; Chavala, Sai H

    2016-01-01

    Reprogramming fibroblasts into induced pluripotent stem cells (iPSC) remains a promising technique for cell replacement therapy. Diverse populations of somatic cells have been examined for their reprogramming potential. Recently, ocular ciliary body epithelial cells (CECs) have been reprogrammed with high reprogramming efficiency and single transcription factor reprogramming, making them an exciting candidate for cellular reprogramming strategies.

  1. Stem cells: a model for screening, discovery and development of drugs.

    PubMed

    Kitambi, Satish Srinivas; Chandrasekar, Gayathri

    2011-01-01

    The identification of normal and cancerous stem cells and the recent advances made in isolation and culture of stem cells have rapidly gained attention in the field of drug discovery and regenerative medicine. The prospect of performing screens aimed at proliferation, directed differentiation, and toxicity and efficacy studies using stem cells offers a reliable platform for the drug discovery process. Advances made in the generation of induced pluripotent stem cells from normal or diseased tissue serves as a platform to perform drug screens aimed at developing cell-based therapies against conditions like Parkinson's disease and diabetes. This review discusses the application of stem cells and cancer stem cells in drug screening and their role in complementing, reducing, and replacing animal testing. In addition to this, target identification and major advances in the field of personalized medicine using induced pluripotent cells are also discussed.

  2. The Effect of Laser Irradiation on Adipose Derived Stem Cell Proliferation and Differentiation

    NASA Astrophysics Data System (ADS)

    Abrahamse, H.; de Villiers, J.; Mvula, B.

    2009-06-01

    There are two fundamental types of stem cells: Embryonic Stem cells and Adult Stem cells. Adult Stem cells have a more restricted potential and can usually differentiate into a few different cell types. In the body these cells facilitate the replacement or repair of damaged or diseased cells in organs. Low intensity laser irradiation was shown to increase stem cell migration and stimulate proliferation and it is thought that treatment of these cells with laser irradiation may increase the stem cell harvest and have a positive effect on the viability and proliferation. Our research is aimed at determining the effect of laser irradiation on differentiation of Adipose Derived Stem Cells (ADSCs) into different cell types using a diode laser with a wavelength of 636 nm and at 5 J/cm2. Confirmation of stem cell characteristics and well as subsequent differentiation were assessed using Western blot analysis and cellular morphology supported by fluorescent live cell imaging. Functionality of subsequent differentiated cells was confirmed by measuring adenosine triphosphate (ATP) production and cell viability.

  3. Stem-Cell Work Yielding New Approach to Disease: Induced Pluripotent Stem-Cell Research Soars, Spurring Dreams of Clinical Applications.

    PubMed

    Mertz, Leslie

    2016-01-01

    Interest in stem cells escalated in 2006 when scientists figured out how to reprogram some specialized adult cells to assume a stem-cell-like state. Called induced pluripotent stem cells (iPSCs), these cells opened the door to a range of potential applications, including generating cells and tissues to replace those that are faulty or missing in patients with cancer, diabetes, cardiovascular disease, or other maladies (Figure 1). Visions of new treatments and even cures for debilitating and fatal illnesses proliferated, and some of that work is well under way (see "A Wealth of Research"). Now, ten years later, those visions are looking more like real possibilities as research moves from the lab to the clinic and expands toward a greater understanding of the basic science behind stem cells and its applications.

  4. Insights into cell-free therapeutic approach: Role of stem cell "soup-ernatant".

    PubMed

    Raik, Shalini; Kumar, Ajay; Bhattacharyya, Shalmoli

    2018-03-01

    Current advances in medicine have revolutionized the field of regenerative medicine dramatically with newly evolved therapies for repair or replacement of degenerating or injured tissues. Stem cells (SCs) can be harvested from different sources for clinical therapeutics, which include fetal tissues, umbilical cord blood, embryos, and adult tissues. SCs can be isolated and differentiated into desired lineages for tissue regeneration and cell replacement therapy. However, several loopholes need to be addressed properly before this can be extended for large-scale therapeutic application. These include a careful approach for patient safety during SC treatments and tolerance of recipients. SC treatments are associated with a number of risk factors and require successful integration and survival of transplanted cells in the desired microenvironment with concurrent tissue regeneration. Recent studies have focused on developing alternatives that can replace the cell-based therapy using paracrine factors. The development of stem "cell free" therapies can be devoted mainly to the use of soluble factors (secretome), extracellular vesicles, and mitochondrial transfer. The present review emphasizes on the paradigms related to the use of SC-based therapeutics and the potential applications of a cell-free approach as an alternative to cell-based therapy in the area of regenerative medicine. © 2017 International Union of Biochemistry and Molecular Biology, Inc.

  5. Effect of Antioxidants and Apoptosis Inhibitors on Cryopreservation of Murine Germ Cells Enriched for Spermatogonial Stem Cells

    PubMed Central

    Lee, Yong-An; Kim, Yong-Hee; Kim, Bang-Jin; Jung, Sang-Eun; Pang, Myeong-Geol; Ryu, Buom-Yong

    2016-01-01

    Spermatogonial stem cells (SSCs) are germline stem cells that serve as the foundation of spermatogenesis to maintain fertility throughout a male’s lifetime. To treat male infertility using stem cell banking systems and transplantation, it is important to be able to preserve SSCs for long periods of time. Therefore, this study was conducted to develop an optimal cryopreservation protocol for SSCs using antioxidants and apoptosis inhibitors in freezing medium. No differences were observed compared to controls when SSCs were cryopreserved in the presence of apoptosis inhibitors by themselves. However, mouse germ cells cryopreserved in basal medium containing the antioxidant hypotaurine (14 mM) resulted in significantly greater proliferation potential and mitochondrial activity. Furthermore, treatment groups with combinations containing 200 mM trehalose and 14 mM hypotaurine showed higher proliferation rates compared to controls. In addition, several serum free conditions were evaluated for SSC cryopreservation. Treatment media containing 10% or 20% knockout serum replacement resulted in similar cryopreservation results compared to media containing FBS. SSC transplantation was also performed to confirm the functionality of SSCs frozen in 14 mM hypotaurine. Donor SSCs formed normal spermatogenic colonies and sperm in the recipient testis. These data indicate that inclusion of 14 mM hypotaurine in cryopreservation media is an effective way to efficiently cryopreserve germ cells enriched for SSCs and that knockout serum replacement can replace FBS in germ cell cryopreservation media. PMID:27548381

  6. Niche displacement of human leukemic stem cells uniquely allows their competitive replacement with healthy HSPCs

    PubMed Central

    Boyd, Allison L.; Campbell, Clinton J.V.; Hopkins, Claudia I.; Fiebig-Comyn, Aline; Russell, Jennifer; Ulemek, Jelena; Foley, Ronan; Leber, Brian; Xenocostas, Anargyros; Collins, Tony J.

    2014-01-01

    Allogeneic hematopoietic stem cell (HSC) transplantation (HSCT) is currently the leading strategy to manage acute myeloid leukemia (AML). However, treatment-related morbidity limits the patient generalizability of HSCT use, and the survival of leukemic stem cells (LSCs) within protective areas of the bone marrow (BM) continues to lead to high relapse rates. Despite growing appreciation for the significance of the LSC microenvironment, it has remained unresolved whether LSCs preferentially situate within normal HSC niches or whether their niche requirements are more promiscuous. Here, we provide functional evidence that the spatial localization of phenotypically primitive human AML cells is restricted to niche elements shared with their normal counterparts, and that their intrinsic ability to initiate and retain occupancy of these niches can be rivaled by healthy hematopoietic stem and progenitor cells (HSPCs). When challenged in competitive BM repopulation assays, primary human leukemia-initiating cells (L-ICs) can be consistently outperformed by HSPCs for BM niche occupancy in a cell dose-dependent manner that ultimately compromises long-term L-IC renewal and subsequent leukemia-initiating capacity. The effectiveness of this approach could be demonstrated using cytokine-induced mobilization of established leukemia from the BM that facilitated the replacement of BM niches with transplanted HSPCs. These findings identify a functional vulnerability of primitive leukemia cells, and suggest that clinical development of these novel transplantation techniques should focus on the dissociation of L-IC–niche interactions to improve competitive replacement with healthy HSPCs during HSCT toward increased survival of patients. PMID:25180064

  7. Rejuvenating Strategies for Stem Cell-based Therapies in Aging

    PubMed Central

    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

  8. Stem cell-biomaterial interactions for regenerative medicine.

    PubMed

    Martino, Sabata; D'Angelo, Francesco; Armentano, Ilaria; Kenny, Josè Maria; Orlacchio, Aldo

    2012-01-01

    The synergism of stem cell biology and biomaterial technology promises to have a profound impact on stem-cell-based clinical applications for tissue regeneration. Biomaterials development is rapidly advancing to display properties that, in a precise and physiological fashion, could drive stem-cell fate both in vitro and in vivo. Thus, the design of novel materials is trying to recapitulate the molecular events involved in the production, clearance and interaction of molecules within tissue in pathologic conditions and regeneration of tissue/organs. In this review we will report on the challenges behind translating stem cell biology and biomaterial innovations into novel clinical therapeutic applications for tissue and organ replacements (graphical abstract). Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Blood stem cells and non-hematological clinical practice: pragmatics before therapeutics.

    PubMed

    Parker, Graham C

    2007-02-01

    There is considerable interest in biological sources for replacement, repair, as well as vascularization of tissue. The remarkable properties of blood stem cells encourage interest in their therapeutic potential. But what are these properties, and how do they influence their clinical potential and the advisability of stem cell use as a therapeutic resource? Rational assessment of the significance of in vitro and animal in vivo data should precede the rush from the bench to the bedside. Basic stem cell research is rife with examples where the truth of the subsequently demonstrated mechanism is stranger than the initial interpretation proved fiction. This review will assess tissue contribution by different blood related stem cells, differing possible mechanisms underlying observed repair phenomena, and consider the potency and pitfalls of stem cell therapeutics.

  10. Kidney regeneration and stem cells.

    PubMed

    Takaori, Koji; Yanagita, Motoko

    2014-01-01

    The kidney has the capacity to recover from ischemic and toxic insults. Although there has been debate about the origin of cells that replace injured epithelial cells, it is now widely recognized that intrinsic surviving tubular cells are responsible for the repair. On the other hand, the cells, which have stem cell-like characteristics, have been isolated in the kidney using various methods, but it remains unknown if these stem cells actually exist in the adult kidney and if they are involved in kidney regeneration. This review will focus on the pathophysiology of kidney regeneration and the contribution of renal stem cells. We also discuss possible therapeutic applications to kidney disease. Copyright © 2013 Wiley Periodicals, Inc.

  11. The reprogramming factor nuclear receptor subfamily 5, group A, member 2 cannot replace octamer-binding transcription factor 4 function in the self-renewal of embryonic stem cells.

    PubMed

    Choi, Kyeng-Won; Oh, Hye-Rim; Lee, Jaeyoung; Lim, Bobae; Han, Yong-Mahn; Oh, Junseo; Kim, Jungho

    2014-02-01

    Although octamer-binding transcription factor 4 (Oct-4) is one of the most intensively studied factors in mammalian development, no cellular genes capable of replacing Oct-4 function in embryonic stem (ES) cells have been found. Recent data show that nuclear receptor subfamily 5, group A, member 2 (Nr5a2) is able to replace Oct-4 function in the reprogramming process; however, it is unclear whether Nr5a2 can replace Oct-4 function in ES cells. In this study, the ability of Nr5a2 to maintain self-renewal and pluripotency in ES cells was investigated. Nr5a2 localized to the nucleus in ES cells, similarly to Oct-4. However, expression of Nr5a2 failed to rescue the stem cell phenotype or to maintain the self-renewal ability of ES cells. Furthermore, as compared with Oct-4-expressing ES cells, Nr5a2-expressing ES cells showed a reduced number of cells in S-phase, did not expand normally, and did not remain in an undifferentiated state. Ectopic expression of Nr5a2 in ES cells was not able to activate transcription of ES cell-specific genes, and gene expression profiling demonstrated differences between Nr5a2-expressing and Oct-4-expressing ES cells. In addition, Nr5a2-expressing ES cells were not able to form teratomas in nude mice. Taken together, these results strongly suggest that the gene regulation properties of Nr5a2 and Oct-4 and their abilities to confer self-renewal and pluripotency of ES cells differ. The present study provides strong evidence that Nr5a2 cannot replace Oct-4 function in ES cells. © 2013 FEBS.

  12. Umbilical cord: an unlimited source of cells differentiable towards dopaminergic neurons

    PubMed Central

    Boroujeni, Mahdi Eskandarian; Gardaneh, Mossa

    2017-01-01

    Cell replacement therapy utilizing mesenchymal stem cells as its main resource holds great promise for ultimate treatment of human neurological disorders. Parkinson's disease (PD) is a common, chronic neurodegenerative disorder hallmarked by localized degeneration of a specific set of dopaminergic neurons within a midbrain sub-region. The specific cell type and confined location of degenerating neurons make cell replacement therapy ideal for PD treatment since it mainly requires replenishment of lost dopaminergic neurons with fresh and functional ones. Endogenous as well as exogenous cell sources have been identified as candidate targets for cell replacement therapy in PD. In this review, umbilical cord mesenchymal stem cells (UCMSCs) are discussed as they provide an inexpensive unlimited reservoir differentiable towards functional dopaminergic neurons that potentially lead to long-lasting behavioral recovery in PD patients. We also present miRNAs-mediated neuronal differentiation of UCMSCs. The UCMSCs bear a number of outstanding characteristics including their non-tumorigenic, low-immunogenic properties that make them ideal for cell replacement therapy purposes. Nevertheless, more investigations as well as controlled clinical trials are required to thoroughly confirm the efficacy of UCMSCs for therapeutic medical-grade applications in PD. PMID:28852404

  13. Transplantation of cerebellar neural stem cells improves motor coordination and neuropathology in Machado-Joseph disease mice.

    PubMed

    Mendonça, Liliana S; Nóbrega, Clévio; Hirai, Hirokazu; Kaspar, Brian K; Pereira de Almeida, Luís

    2015-02-01

    Machado-Joseph disease is a neurodegenerative disease without effective treatment. Patients with Machado-Joseph disease exhibit significant motor impairments such as gait ataxia, associated with multiple neuropathological changes including mutant ATXN3 inclusions, marked neuronal loss and atrophy of the cerebellum. Thus, an effective treatment of symptomatic patients with Machado-Joseph disease may require cell replacement, which we investigated in this study. For this purpose, we injected cerebellar neural stem cells into the cerebellum of adult Machado-Joseph disease transgenic mice and assessed the effect on the neuropathology, neuroinflammation mediators and neurotrophic factor levels and motor coordination. We found that upon transplantation into the cerebellum of adult Machado-Joseph disease mice, cerebellar neural stem cells differentiate into neurons, astrocytes and oligodendrocytes. Importantly, cerebellar neural stem cell transplantation mediated a significant and robust alleviation of the motor behaviour impairments, which correlated with preservation from Machado-Joseph disease-associated neuropathology, namely reduction of Purkinje cell loss, reduction of cellular layer shrinkage and mutant ATXN3 aggregates. Additionally, a significant reduction of neuroinflammation and an increase of neurotrophic factors levels was observed, indicating that transplantation of cerebellar neural stem cells also triggers important neuroprotective effects. Thus, cerebellar neural stem cells have the potential to be used as a cell replacement and neuroprotective approach for Machado-Joseph disease therapy. © The Author (2014). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. [Cell therapy for Parkinson's disease: III. Neonatal, fetal and embryonic stem cell-based applications].

    PubMed

    Anisimov, S V

    2009-01-01

    Motor dysfunctions in Parkinson's disease are believed to be primarily due to the degeneration of dopaminergic neurons located in the substantia nigra pars compacta. Numerous cell replacement therapy approaches have been developed and tested, including these based on donor cell transplantation (embryonic and adult tissue-derived), adult mesenchymal stem cells (hMSCs)-, neural stem cells (hNSCs)- and finally human embryonic stem cells (hESCs)-based. Despite the progress achieved, numerous difficulties prevent wider practical application of stem cell-based therapy approaches for the treatment of Parkinson's disease. Among the latter, ethical, safety and technical issues stand out. Current series of reviews (Cell therapy for Parkinson's disease: I. Embryonic and adult donor tissue-based applications; II. Adult stem cell-based applications; III. Neonatal, fetal and embryonic stem cell-based applications; IV. Risks and future trends) aims providing a balanced and updated view on various issues associated with cell types (including stem cells) in regards to their potential in the treatment of Parkinson's disease. Essential features of the individual cell subtypes, principles of available cell handling protocols, transplantation, and safety issues are discussed extensively.

  15. Stem Cell-Based Therapies for Polyglutamine Diseases.

    PubMed

    Mendonça, Liliana S; Onofre, Isabel; Miranda, Catarina Oliveira; Perfeito, Rita; Nóbrega, Clévio; de Almeida, Luís Pereira

    2018-01-01

    Polyglutamine (polyQ) diseases are a family of neurodegenerative disorders with very heterogeneous clinical presentations, although with common features such as progressive neuronal death. Thus, at the time of diagnosis patients might present an extensive and irreversible neuronal death demanding cell replacement or support provided by cell-based therapies. For this purpose stem cells, which include diverse populations ranging from embryonic stem cells (ESCs), to fetal stem cells, mesenchymal stromal cells (MSCs) or induced pluripotent stem cells (iPSCs) have remarkable potential to promote extensive brain regeneration and recovery in neurodegenerative disorders. This regenerative potential has been demonstrated in exciting pre and clinical assays. However, despite these promising results, several drawbacks are hampering their successful clinical implementation. Problems related to ethical issues, quality control of the cells used and the lack of reliable models for the efficacy assessment of human stem cells. In this chapter the main advantages and disadvantages of the available sources of stem cells as well as their efficacy and potential to improve disease outcomes are discussed.

  16. A Newly Defined and Xeno-Free Culture Medium Supports Every-Other-Day Medium Replacement in the Generation and Long-Term Cultivation of Human Pluripotent Stem Cells.

    PubMed

    Ahmadian Baghbaderani, Behnam; Tian, Xinghui; Scotty Cadet, Jean; Shah, Kevan; Walde, Amy; Tran, Huan; Kovarcik, Don Paul; Clarke, Diana; Fellner, Thomas

    2016-01-01

    Human pluripotent stem cells (hPSCs) present an unprecedented opportunity to advance human health by offering an alternative and renewable cell resource for cellular therapeutics and regenerative medicine. The present demand for high quality hPSCs for use in both research and clinical studies underscores the need to develop technologies that will simplify the cultivation process and control variability. Here we describe the development of a robust, defined and xeno-free hPSC medium that supports reliable propagation of hPSCs and generation of human induced pluripotent stem cells (hiPSCs) from multiple somatic cell types; long-term serial subculturing of hPSCs with every-other-day (EOD) medium replacement; and banking fully characterized hPSCs. The hPSCs cultured in this medium for over 40 passages are genetically stable, retain high expression levels of the pluripotency markers TRA-1-60, TRA-1-81, Oct-3/4 and SSEA-4, and readily differentiate into ectoderm, mesoderm and endoderm. Importantly, the medium plays an integral role in establishing a cGMP-compliant process for the manufacturing of hiPSCs that can be used for generation of clinically relevant cell types for cell replacement therapy applications.

  17. Neutral competition of stem cells is skewed by proliferative changes downstream of Hh and Hpo.

    PubMed

    Amoyel, Marc; Simons, Benjamin D; Bach, Erika A

    2014-10-16

    Neutral competition, an emerging feature of stem cell homeostasis, posits that individual stem cells can be lost and replaced by their neighbors stochastically, resulting in chance dominance of a clone at the niche. A single stem cell with an oncogenic mutation could bias this process and clonally spread the mutation throughout the stem cell pool. The Drosophila testis provides an ideal system for testing this model. The niche supports two stem cell populations that compete for niche occupancy. Here, we show that cyst stem cells (CySCs) conform to the paradigm of neutral competition and that clonal deregulation of either the Hedgehog (Hh) or Hippo (Hpo) pathway allows a single CySC to colonize the niche. We find that the driving force behind such behavior is accelerated proliferation. Our results demonstrate that a single stem cell colonizes its niche through oncogenic mutation by co-opting an underlying homeostatic process. © 2014 The Authors.

  18. Tooth replacement and putative odontogenic stem cell niches in pharyngeal dentition of medaka (Oryzias latipes).

    PubMed

    Abduweli, Dawud; Baba, Otto; Tabata, Makoto J; Higuchi, Kazunori; Mitani, Hiroshi; Takano, Yoshiro

    2014-04-01

    The small-sized teleost fish medaka, Oryzias latipes, has as many as 1000 pharyngeal teeth undergoing continuous replacement. In this study, we sought to identify the tooth-forming units and determine its replacement cycles, and further localize odontogenic stem cell niches in the pharyngeal dentition of medaka to gain insights into the mechanisms whereby continuous tooth replacement is maintained. Three-dimensional reconstruction of pharyngeal epithelium and sequential fluorochrome labeling of pharyngeal bones and teeth indicated that the individual functional teeth and their successional teeth were organized in families, each comprising up to five generations of teeth and successional tooth germs, and that the replacement cycle of functional teeth was approximately 4 weeks. BrdU label/chase experiments confirmed the existence of clusters of label-retaining epithelial cells at the posterior end of each tooth family where the expression of pluripotency marker Sox2 was confirmed by in situ hybridization. Label-retaining cells were also identified in the mesoderm immediately adjacent to the posterior end of each tooth family. These data suggest the importance of existence of slow-cycling dental epithelial cells and Sox2 expressions at the posterior end of each tooth family to maintain continuous tooth formation and replacement in the pharyngeal dentition of medaka.

  19. Long-term maintenance of human induced pluripotent stem cells by automated cell culture system.

    PubMed

    Konagaya, Shuhei; Ando, Takeshi; Yamauchi, Toshiaki; Suemori, Hirofumi; Iwata, Hiroo

    2015-11-17

    Pluripotent stem cells, such as embryonic stem cells and induced pluripotent stem (iPS) cells, are regarded as new sources for cell replacement therapy. These cells can unlimitedly expand under undifferentiated conditions and be differentiated into multiple cell types. Automated culture systems enable the large-scale production of cells. In addition to reducing the time and effort of researchers, an automated culture system improves the reproducibility of cell cultures. In the present study, we newly designed a fully automated cell culture system for human iPS maintenance. Using an automated culture system, hiPS cells maintained their undifferentiated state for 60 days. Automatically prepared hiPS cells had a potency of differentiation into three germ layer cells including dopaminergic neurons and pancreatic cells.

  20. Induced pluripotent stem cells: advances to applications

    PubMed Central

    Nelson, Timothy J; Martinez-Fernandez, Almudena; Yamada, Satsuki; Ikeda, Yasuhiro; Perez-Terzic, Carmen; Terzic, Andre

    2010-01-01

    Induced pluripotent stem cell (iPS) technology has enriched the armamentarium of regenerative medicine by introducing autologous pluripotent progenitor pools bioengineered from ordinary somatic tissue. Through nuclear reprogramming, patient-specific iPS cells have been derived and validated. Optimizing iPS-based methodology will ensure robust applications across discovery science, offering opportunities for the development of personalized diagnostics and targeted therapeutics. Here, we highlight the process of nuclear reprogramming of somatic tissues that, when forced to ectopically express stemness factors, are converted into bona fide pluripotent stem cells. Bioengineered stem cells acquire the genuine ability to generate replacement tissues for a wide-spectrum of diseased conditions, and have so far demonstrated therapeutic benefit upon transplantation in model systems of sickle cell anemia, Parkinson’s disease, hemophilia A, and ischemic heart disease. The field of regenerative medicine is therefore primed to adopt and incorporate iPS cell-based advancements as a next generation stem cell platforms. PMID:21165156

  1. Potential feasibility of dental stem cells for regenerative therapies: stem cell transplantation and whole-tooth engineering.

    PubMed

    Nakahara, Taka

    2011-07-01

    Multipotent mesenchymal stem cells from bone marrow are expected to be a somatic stem cell source for the development of new cell-based therapy in regenerative medicine. However, dental clinicians are unlikely to carry out autologous cell/tissue collection from patients (i.e., marrow aspiration) as a routine procedure in their clinics; hence, the utilization of bone marrow stem cells seems impractical in the dental field. Dental tissues harvested from extracted human teeth are well known to contain highly proliferative and multipotent stem cell compartments and are considered to be an alternative autologous cell source in cell-based medicine. This article provides a short overview of the ongoing studies for the potential application of dental stem cells and suggests the utilization of 2 concepts in future regenerative medicine: (1) dental stem cell-based therapy for hepatic and other systemic diseases and (2) tooth replacement therapy using the bioengineered human whole tooth, called the "test-tube dental implant." Regenerative therapies will bring new insights and benefits to the fields of clinical medicine and dentistry.

  2. Stem cell therapy. Use of differentiated pluripotent stem cells as replacement therapy for treating disease.

    PubMed

    Fox, Ira J; Daley, George Q; Goldman, Steven A; Huard, Johnny; Kamp, Timothy J; Trucco, Massimo

    2014-08-22

    Pluripotent stem cells (PSCs) directed to various cell fates holds promise as source material for treating numerous disorders. The availability of precisely differentiated PSC-derived cells will dramatically affect blood component and hematopoietic stem cell therapies and should facilitate treatment of diabetes, some forms of liver disease and neurologic disorders, retinal diseases, and possibly heart disease. Although an unlimited supply of specific cell types is needed, other barriers must be overcome. This review of the state of cell therapies highlights important challenges. Successful cell transplantation will require optimizing the best cell type and site for engraftment, overcoming limitations to cell migration and tissue integration, and occasionally needing to control immunologic reactivity, as well as a number of other challenges. Collaboration among scientists, clinicians, and industry is critical for generating new stem cell-based therapies. Copyright © 2014, American Association for the Advancement of Science.

  3. Perspectives for the treatment of sensorineural hearing loss by cellular regeneration of the inner ear.

    PubMed

    Almeida-Branco, Mario S; Cabrera, Sonia; Lopez-Escamez, Jose A

    2015-01-01

    Sensorineural hearing loss is a caused by the loss of the cochlear hair cells with the consequent deafferentation of spiral ganglion neurons. Humans do not show endogenous cellular regeneration in the inner ear and there is no exogenous therapy that allows the replacement of the damaged hair cells. Currently, treatment is based on the use of hearing aids and cochlear implants that present different outcomes, some difficulties in auditory discrimination and a limited useful life. More advanced technology is hindered by the functional capacity of the remaining spiral ganglion neurons. The latest advances with stem cell therapy and cellular reprogramming have developed several possibilities to induce endogenous regeneration or stem cell transplantation to replace damaged inner ear hair cells and restore hearing function. With further knowledge of the cellular and molecular biology of the inner ear and its embryonic development, it will be possible to use induced stem cells as in vitro models of disease and as replacement cellular therapy. Investigation in this area is focused on generating cellular therapy with clinical use for the treatment of profound sensorineural hearing loss. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

  4. From fibroblasts and stem cells: implications for cell therapies and somatic cloning.

    PubMed

    Kues, Wilfried A; Carnwath, Joseph W; Niemann, Heiner

    2005-01-01

    Pluripotent embryonic stem cells (ESCs) from the inner cell mass of early murine and human embryos exhibit extensive self-renewal in culture and maintain their ability to differentiate into all cell lineages. These features make ESCs a suitable candidate for cell-replacement therapy. However, the use of early embryos has provoked considerable public debate based on ethical considerations. From this standpoint, stem cells derived from adult tissues are a more easily accepted alternative. Recent results suggest that adult stem cells have a broader range of potency than imagined initially. Although some claims have been called into question by the discovery that fusion between the stem cells and differentiated cells can occur spontaneously, in other cases somatic stem cells have been induced to commit to various lineages by the extra- or intracellular environment. Recent data from our laboratory suggest that changes in culture conditions can expand a subpopulation of cells with a pluripotent phenotype from primary fibroblast cultures. The present paper critically reviews recent data on the potency of somatic stem cells, methods to modify the potency of somatic cells and implications for cell-based therapies.

  5. Characterization of Nestin-positive stem Leydig cells as a potential source for the treatment of testicular Leydig cell dysfunction

    PubMed Central

    Jiang, Mei Hua; Cai, Bing; Tuo, Ying; Wang, Jiancheng; Zang, Zhi Jun; Tu, Xiang'an; Gao, Yong; Su, Zhijian; Li, Weiqiang; Li, Guilan; Zhang, Min; Jiao, Jianwei; Wan, Zi; Deng, Chunhua; Lahn, Bruce T; Xiang, Andy Peng

    2014-01-01

    The ability to identify and isolate lineage-specific stem cells from adult tissues could facilitate cell replacement therapy. Leydig cells (LCs) are the primary source of androgen in the mammalian testis, and the prospective identification of stem Leydig cells (SLCs) may offer new opportunities for treating testosterone deficiency. Here, in a transgenic mouse model expressing GFP driven by the Nestin (Nes) promoter, we observed Nes-GFP+ cells located in the testicular interstitial compartment where SLCs normally reside. We showed that these Nes-GFP+ cells expressed LIFR and PDGFR-α, but not LC lineage markers. We further observed that these cells were capable of clonogenic self-renewal and extensive proliferation in vitro and could differentiate into neural or mesenchymal cell lineages, as well as LCs, with the ability to produce testosterone, under defined conditions. Moreover, when transplanted into the testes of LC-disrupted or aging models, the Nes-GFP+ cells colonized the interstitium and partially increased testosterone production, and then accelerated meiotic and post-meiotic germ cell recovery. In addition, we further demonstrated that CD51 might be a putative cell surface marker for SLCs, similar with Nestin. Taken together, these results suggest that Nes-GFP+ cells from the testis have the characteristics of SLCs, and our study would shed new light on developing stem cell replacement therapy for testosterone deficiency. PMID:25418539

  6. [Cell therapy for Parkinson's disease: IV. Risks and future trends].

    PubMed

    Anisimov, S V

    2009-01-01

    Motor dysfunctions in Parkinson's disease are believed to be primarily due to the degeneration of dopaminergic neurons located in the substantia nigra pars compacta. Numerous cell replacement therapy approaches have been developed and tested, including these based on donor cell transplantation (embryonic and adult tissue-derived), adult mesenchymal stem cells (hMSCs)-, neural stem cells (hNSCs)- and finally human embryonic stem cells (hESCs)-based. Despite the progress achieved, numerous difficulties prevent wider practical application of stem cell-based therapy approaches for the treatment of Parkinson's disease. Among the latter, ethical, safety and technical issues stand out. Current series of reviews (Cell therapy for Parkinson's disease: I. Embryonic and adult donor tissue-based applications; II. Adult stem cell-based applications; III. Neonatal, fetal and embryonic stem cell-based applications; IV. Risks and future trends) aims providing a balanced and updated view on various issues associated with cell types (including stem cells) in regards to their potential in the treatment of Parkinson's disease. Essential features of the individual cell subtypes, principles of available cell handling protocols, transplantation, and safety issues are discussed extensively.

  7. Stem cells and calcium signaling.

    PubMed

    Tonelli, Fernanda M P; Santos, Anderson K; Gomes, Dawidson A; da Silva, Saulo L; Gomes, Katia N; Ladeira, Luiz O; Resende, Rodrigo R

    2012-01-01

    The increasing interest in stem cell research is linked to the promise of developing treatments for many lifethreatening, debilitating diseases, and for cell replacement therapies. However, performing these therapeutic innovations with safety will only be possible when an accurate knowledge about the molecular signals that promote the desired cell fate is reached. Among these signals are transient changes in intracellular Ca(2+) concentration [Ca(2+)](i). Acting as an intracellular messenger, Ca(2+) has a key role in cell signaling pathways in various differentiation stages of stem cells. The aim of this chapter is to present a broad overview of various moments in which Ca(2+)-mediated signaling is essential for the maintenance of stem cells and for promoting their development and differentiation, also focusing on their therapeutic potential.

  8. Regenerative Medicine: Solution in Sight.

    PubMed

    Wang, Qingjie; Stern, Jeffrey H; Temple, Sally

    2016-01-01

    The retina, like other central nervous system tissues, has poor regenerative properties in humans. Therefore, diseases that cause retinal cell loss, such as Age-related macular degeneration (AMD), retinitis pigmentosa (RP), Leber congenital amaurosis, Usher syndrome, glaucoma, and diabetic retinopathy, typically result in permanent visual impairment. Stem cell technologies have revolutionized our ability to produce neural cells in abundant supply. Much stem cell research effort is focused on producing the required cell types for cell replacement, or to generate disease-in-a-dish models to elucidate novel disease mechanisms for therapeutic development. Here we review the recent advances in stem cell studies relevant to producing RPE and retinal cells, and highlight future directions.

  9. Application of stem cells for cardiovascular grafts tissue engineering.

    PubMed

    Wu, Kaihong; Liu, Ying Long; Cui, Bin; Han, Zhongchao

    2006-06-01

    Congenital and acquired heart diseases are leading causes of morbidity and mortality world-wide. Currently, the synthetic materials or bioprosthetic replacement devices for cardiovascular surgery are imperfect and subject patients to one or more ongoing risks including thrombosis, limited durability and need for reoperations due to lack of growth in children and young adults. Suitable replacement grafts should have appropriate characteristics, including resistance to infection, low immunogenicity, good biocompatability and thromboresistance, with appropriate mechanical and physiological properties. Tissue engineering is a new scientific field aiming at fabrication of living, autologous grafts having structure or function properties that can be used to restore, maintain or improve tissue function. The use of autologous stem cells in cardiovascular tissue engineering is quite promising due to their capacity of self-renewal, high proliferation, and differentiation into specialized progeny. Progress has been made in engineering the various components of the cardiovascular system, including myocardial constructs, heart valves, and vascular patches or conduits with autologous stem cells. This paper will review the current achievements in stem cell-based cardiovascular grafts tissue engineering, with an emphasis on its clinical or possible clinical use in cardiovascular surgery.

  10. Current concept in neural regeneration research: NSCs isolation, characterization and transplantation in various neurodegenerative diseases and stroke: A review

    PubMed Central

    Vishwakarma, Sandeep K.; Bardia, Avinash; Tiwari, Santosh K.; Paspala, Syed A.B.; Khan, Aleem A.

    2013-01-01

    Since last few years, an impressive amount of data has been generated regarding the basic in vitro and in vivo biology of neural stem cells (NSCs) and there is much far hope for the success in cell replacement therapies for several human neurodegenerative diseases and stroke. The discovery of adult neurogenesis (the endogenous production of new neurons) in the mammalian brain more than 40 years ago has resulted in a wealth of knowledge about stem cells biology in neuroscience research. Various studies have done in search of a suitable source for NSCs which could be used in animal models to understand the basic and transplantation biology before treating to human. The difficulties in isolating pure population of NSCs limit the study of neural stem behavior and factors that regulate them. Several studies on human fetal brain and spinal cord derived NSCs in animal models have shown some interesting results for cell replacement therapies in many neurodegenerative diseases and stroke models. Also the methods and conditions used for in vitro culture of these cells provide an important base for their applicability and specificity in a definite target of the disease. Various important developments and modifications have been made in stem cells research which is needed to be more specified and enrolment in clinical studies using advanced approaches. This review explains about the current perspectives and suitable sources for NSCs isolation, characterization, in vitro proliferation and their use in cell replacement therapies for the treatment of various neurodegenerative diseases and strokes. PMID:25685495

  11. Stem cell application for osteoarthritis in the knee joint: A minireview.

    PubMed

    Uth, Kristin; Trifonov, Dimitar

    2014-11-26

    Knee osteoarthritis is a chronic, indolent disease that will affect an ever increasing number of patients, especially the elderly and the obese. It is characterized by degeneration of the cartilage substance inside the knee which leads to pain, stiffness and tenderness. By some estimations in 2030, only in the United States, this medical condition will burden 67 million people. While conventional treatments like physiotherapy or drugs offer temporary relief of clinical symptoms, restoration of normal cartilage function has been difficult to achieve. Moreover, in severe cases of knee osteoarthritis total knee replacement may be required. Total knee replacements come together with high effort and costs and are not always successful. The aim of this review is to outline the latest advances in stem cell therapy for knee osteoarthritis as well as highlight some of the advantages of stem cell therapy over traditional approaches aimed at restoration of cartilage function in the knee. In addition to the latest advances in the field, challenges associated with stem cell therapy regarding knee cartilage regeneration and chondrogenesis in vitro and in vivo are also outlined and analyzed. Furthermore, based on their critical assessment of the present academic literature the authors of this review share their vision about the future of stem cell applications in the treatment of knee osteoarthritis.

  12. Induced pluripotent stem cells in Alzheimer's disease: applications for disease modeling and cell-replacement therapy.

    PubMed

    Yang, Juan; Li, Song; He, Xi-Biao; Cheng, Cheng; Le, Weidong

    2016-05-17

    Alzheimer's disease (AD) is the most common cause of dementia in those over the age of 65. While a numerous of disease-causing genes and risk factors have been identified, the exact etiological mechanisms of AD are not yet completely understood, due to the inability to test theoretical hypotheses on non-postmortem and patient-specific research systems. The use of recently developed and optimized induced pluripotent stem cells (iPSCs) technology may provide a promising platform to create reliable models, not only for better understanding the etiopathological process of AD, but also for efficient anti-AD drugs screening. More importantly, human-sourced iPSCs may also provide a beneficial tool for cell-replacement therapy against AD. Although considerable progress has been achieved, a number of key challenges still require to be addressed in iPSCs research, including the identification of robust disease phenotypes in AD modeling and the clinical availabilities of iPSCs-based cell-replacement therapy in human. In this review, we highlight recent progresses of iPSCs research and discuss the translational challenges of AD patients-derived iPSCs in disease modeling and cell-replacement therapy.

  13. Advances in translational inner ear stem cell research.

    PubMed

    Warnecke, Athanasia; Mellott, Adam J; Römer, Ariane; Lenarz, Thomas; Staecker, Hinrich

    2017-09-01

    Stem cell research is expanding our understanding of developmental biology as well as promising the development of new therapies for a range of different diseases. Within hearing research, the use of stem cells has focused mainly on cell replacement. Stem cells however have a broad range of other potential applications that are just beginning to be explored in the ear. Mesenchymal stem cells are an adult derived stem cell population that have been shown to produce growth factors, modulate the immune system and can differentiate into a wide variety of tissue types. Potential advantages of mesenchymal/adult stem cells are that they have no ethical constraints on their use. However, appropriate regulatory oversight seems necessary in order to protect patients from side effects. Disadvantages may be the lack of efficacy in many preclinical studies. But if proven safe and efficacious, they are easily translatable to clinical trials. The current review will focus on the potential application on mesenchymal stem cells for the treatment of inner ear disorders. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Guiding osteogenesis of mesenchymal stem cells using carbon-based nanomaterials

    NASA Astrophysics Data System (ADS)

    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.

  15. Applications of patient-specific induced pluripotent stem cells; focused on disease modeling, drug screening and therapeutic potentials for liver disease.

    PubMed

    Chun, Yong Soon; Chaudhari, Pooja; Jang, Yoon-Young

    2010-12-14

    The recent advances in the induced pluripotent stem cell (iPSC) research have significantly changed our perspectives on regenerative medicine by providing researchers with a unique tool to derive disease-specific stem cells for study. In this review, we describe the human iPSC generation from developmentally diverse origins (i.e. endoderm-, mesoderm-, and ectoderm- tissue derived human iPSCs) and multistage hepatic differentiation protocols, and discuss both basic and clinical applications of these cells including disease modeling, drug toxicity screening/drug discovery, gene therapy and cell replacement therapy.

  16. The promises of stem cells: stem cell therapy for movement disorders.

    PubMed

    Mochizuki, Hideki; Choong, Chi-Jing; Yasuda, Toru

    2014-01-01

    Despite the multitude of intensive research, the exact pathophysiological mechanisms underlying movement disorders including Parkinson's disease, multiple system atrophy and Huntington's disease remain more or less elusive. Treatments to halt these disease progressions are currently unavailable. With the recent induced pluripotent stem cells breakthrough and accomplishment, stem cell research, as the vast majority of scientists agree, holds great promise for relieving and treating debilitating movement disorders. As stem cells are the precursors of all cells in the human body, an understanding of the molecular mechanisms that govern how they develop and work would provide us many fundamental insights into human biology of health and disease. Moreover, stem-cell-derived neurons may be a renewable source of replacement cells for damaged neurons in movement disorders. While stem cells show potential for regenerative medicine, their use as tools for research and drug testing is thought to have more immediate impact. The use of stem-cell-based drug screening technology could be a big boost in drug discovery for these movement disorders. Particular attention should also be given to the involvement of neural stem cells in adult neurogenesis so as to encourage its development as a therapeutic option. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Generation of Functional Human Retinal Ganglion Cells with Target Specificity from Pluripotent Stem Cells by Chemically Defined Recapitulation of Developmental Mechanism.

    PubMed

    Teotia, Pooja; Chopra, Divyan A; Dravid, Shashank Manohar; Van Hook, Matthew J; Qiu, Fang; Morrison, John; Rizzino, Angie; Ahmad, Iqbal

    2017-03-01

    Glaucoma is a complex group of diseases wherein a selective degeneration of retinal ganglion cells (RGCs) lead to irreversible loss of vision. A comprehensive approach to glaucomatous RGC degeneration may include stem cells to functionally replace dead neurons through transplantation and understand RGCs vulnerability using a disease in a dish stem cell model. Both approaches require the directed generation of stable, functional, and target-specific RGCs from renewable sources of cells, that is, the embryonic stem cells and induced pluripotent stem cells. Here, we demonstrate a rapid and safe, stage-specific, chemically defined protocol that selectively generates RGCs across species, including human, by recapitulating the developmental mechanism. The de novo generated RGCs from pluripotent cells are similar to native RGCs at the molecular, biochemical, functional levels. They also express axon guidance molecules, and discriminate between specific and nonspecific targets, and are nontumorigenic. Stem Cells 2017;35:572-585. © 2016 AlphaMed Press.

  18. Human cardiomyocyte generation from pluripotent stem cells: A state-of-art.

    PubMed

    Talkhabi, Mahmood; Aghdami, Nasser; Baharvand, Hossein

    2016-01-15

    The human heart is considered a non-regenerative organ. Worldwide, cardiovascular diseases continue to be the leading cause of death. Despite advances in cardiac treatment, myocardial repair remains severely limited by the lack of an appropriate source of viable cardiomyocytes (CMs) to replace damaged tissue. Human pluripotent stem cells (hPSCs), embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) can efficiently be differentiated into functional CMs necessary for cell replacement therapy and other potential applications. The number of protocols that derive CMs from hPSCs has increased exponentially over the past decade following observation of the first human beating CMs. A number of highly efficient, chemical based protocols have been developed to generate human CMs (hCMs) in small-scale and large-scale suspension systems. To reduce the heterogeneity of hPSC-derived CMs, the differentiation protocols were modulated to exclusively generate atrial-, ventricular-, and nodal-like CM subtypes. Recently, remarkable advances have been achieved in hCM generation including chemical-based cardiac differentiation, cardiac subtype specification, large-scale suspension culture differentiation, and development of chemically defined culture conditions. These hCMs could be useful particularly in the context of in vitro disease modeling, pharmaceutical screening and in cellular replacement therapies once the safety issues are overcome. Herein we review recent progress in the in vitro generation of CMs and cardiac subtypes from hPSCs and discuss their potential applications and current limitations. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Stem-cell-based, tissue engineered tracheal replacement in a child: a 2-year follow-up study

    PubMed Central

    Elliott, Martin J; De Coppi, Paolo; Speggiorin, Simone; Roebuck, Derek; Butler, Colin R; Samuel, Edward; Crowley, Claire; McLaren, Clare; Fierens, Anja; Vondrys, David; Cochrane, Lesley; Jephson, Christopher; Janes, Samuel; Beaumont, Nicholas J; Cogan, Tristan; Bader, Augustinus; Seifalian, Alexander M; Hsuan, J Justin; Lowdell, Mark W; Birchall, Martin A

    2015-01-01

    Summary Background Stem-cell-based, tissue engineered transplants might offer new therapeutic options for patients, including children, with failing organs. The reported replacement of an adult airway using stem cells on a biological scaffold with good results at 6 months supports this view. We describe the case of a child who received a stem-cell-based tracheal replacement and report findings after 2 years of follow-up. Methods A 12-year-old boy was born with long-segment congenital tracheal stenosis and pulmonary sling. His airway had been maintained by metal stents, but, after failure, a cadaveric donor tracheal scaffold was decellularised. After a short course of granulocyte colony stimulating factor, bone marrow mesenchymal stem cells were retrieved preoperatively and seeded onto the scaffold, with patches of autologous epithelium. Topical human recombinant erythropoietin was applied to encourage angiogenesis, and transforming growth factor β to support chondrogenesis. Intravenous human recombinant erythropoietin was continued postoperatively. Outcomes were survival, morbidity, endoscopic appearance, cytology and proteomics of brushings, and peripheral blood counts. Findings The graft revascularised within 1 week after surgery. A strong neutrophil response was noted locally for the first 8 weeks after surgery, which generated luminal DNA neutrophil extracellular traps. Cytological evidence of restoration of the epithelium was not evident until 1 year. The graft did not have biomechanical strength focally until 18 months, but the patient has not needed any medical intervention since then. 18 months after surgery, he had a normal chest CT scan and ventilation-perfusion scan and had grown 11 cm in height since the operation. At 2 years follow-up, he had a functional airway and had returned to school. Interpretation Follow-up of the first paediatric, stem-cell-based, tissue-engineered transplant shows potential for this technology but also highlights the need for further research. Funding Great Ormond Street Hospital NHS Trust, The Royal Free Hampstead NHS Trust, University College Hospital NHS Foundation Trust, and Region of Tuscany. PMID:22841419

  20. Potential antitumor therapeutic strategies of human amniotic membrane and amniotic fluid-derived stem cells.

    PubMed

    Kang, N-H; Hwang, K-A; Kim, S U; Kim, Y-B; Hyun, S-H; Jeung, E-B; Choi, K-C

    2012-08-01

    As stem cells are capable of self-renewal and can generate differentiated progenies for organ development, they are considered as potential source for regenerative medicine and tissue replacement after injury or disease. Along with this capacity, stem cells have the therapeutic potential for treating human diseases including cancers. According to the origins, stem cells are broadly classified into two types: embryonic stem cells (ESCs) and adult stem cells. In terms of differentiation potential, ESCs are pluripotent and adult stem cells are multipotent. Amnion, which is a membranous sac that contains the fetus and amniotic fluid and functions in protecting the developing embryo during gestation, is another stem cell source. Amnion-derived stem cells are classified as human amniotic membrane-derived epithelial stem cells, human amniotic membrane-derived mesenchymal stem cells and human amniotic fluid-derived stem cells. They are in an intermediate stage between pluripotent ESCs and lineage-restricted adult stem cells, non-tumorigenic, and contribute to low immunogenicity and anti-inflammation. Furthermore, they are easily available and do not cause any controversial issues in their recovery and applications. Not only are amnion-derived stem cells applicable in regenerative medicine, they have anticancer capacity. In non-engineered stem cells transplantation strategies, amnion-derived stem cells effectively target the tumor and suppressed the tumor growth by expressing cytotoxic cytokines. Additionally, they also have a potential as novel delivery vehicles transferring therapeutic genes to the cancer formation sites in gene-directed enzyme/prodrug combination therapy. Owing to their own advantageous properties, amnion-derived stem cells are emerging as a new candidate in anticancer therapy.

  1. Application of Stem Cell Technology in Dental Regenerative Medicine.

    PubMed

    Feng, Ruoxue; Lengner, Chistopher

    2013-07-01

    In this review, we summarize the current literature regarding the isolation and characterization of dental tissue-derived stem cells and address the potential of these cell types for use in regenerative cell transplantation therapy. Looking forward, platforms for the delivery of stem cells via scaffolds and the use of growth factors and cytokines for enhancing dental stem cell self-renewal and differentiation are discussed. We aim to understand the developmental origins of dental tissues in an effort to elucidate the molecular pathways governing the genesis of somatic dental stem cells. The advantages and disadvantages of several dental stem cells are discussed, including the developmental stage and specific locations from which these cells can be purified. In particular, stem cells from human exfoliated deciduous teeth may act as a very practical and easily accessibly reservoir for autologous stem cells and hold the most value in stem cell therapy. Dental pulp stem cells and periodontal ligament stem cells should also be considered for their triple lineage differentiation ability and relative ease of isolation. Further, we address the potentials and limitations of induced pluripotent stem cells as a cell source in dental regenerative. From an economical and a practical standpoint, dental stem cell therapy would be most easily applied in the prevention of periodontal ligament detachment and bone atrophy, as well as in the regeneration of dentin-pulp complex. In contrast, cell-based tooth replacement due to decay or other oral pathology seems, at the current time, an untenable approach.

  2. Derivation of porcine pluripotent stem cells for biomedical research.

    PubMed

    Shiue, Yow-Ling; Yang, Jenn-Rong; Liao, Yu-Jing; Kuo, Ting-Yung; Liao, Chia-Hsin; Kang, Ching-Hsun; Tai, Chein; Anderson, Gary B; Chen, Lih-Ren

    2016-07-01

    Pluripotent stem cells including embryonic stem cells (ESCs), embryonic germ cells (EGCs), and induced pluripotent stem cells (iPSCs) are capable of self-renew and limitlessly proliferating in vitro with undifferentiated characteristics. They are able to differentiate in vitro, spontaneously or responding to suitable signals, into cells of all three primary germ layers. Consequently, these pluripotent stem cells will be valuable sources for cell replacement therapy in numerous disorders. However, the promise of human ESCs and EGCs is cramped by the ethical argument about destroying embryos and fetuses for cell line creation. Moreover, there are still carcinogenic risks existing toward the goal of clinical application for human ESCs, EGCs, and iPSCs. Therefore, a suitable animal model for stem cell research will benefit the further development of human stem cell technology. The pigs, on the basis of their similarity in anatomy, immunology, physiology, and biochemical properties, have been wide used as model animals in the study of various human diseases. The development of porcine pluripotent stem cell lines will hold the opportunity to provide an excellent material for human counterpart to the transplantation in biomedical research and further development of cell-based therapeutic strategy. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Müller stem cell dependent retinal regeneration.

    PubMed

    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.

  4. Placenta-an alternative source of stem cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Matikainen, Tiina; Laine, Jarmo

    2005-09-01

    The two most promising practical applications of human stem cells are cellular replacement therapies in human disease and toxicological screening of candidate drug molecules. Both require a source of human stem cells that can be isolated, purified, expanded in number and differentiated into the cell type of choice in a controlled manner. Currently, uses of both embryonic and adult stem cells are investigated. While embryonic stem cells are pluripotent and can differentiate into any specialised cell type, their use requires establishment of embryonic stem cell lines using the inner cell mass of an early pre-implantation embryo. As the blastocyst ismore » destroyed during the process, ethical issues need to be carefully considered. The use of embryonic stem cells is also limited by the difficulties in growing large numbers of the cells without inducing spontaneous differentiation, and the problems in controlling directed differentiation of the cells. The use of adult stem cells, typically derived from bone marrow, but also from other tissues, is ethically non-controversial but their differentiation potential is more limited than that of the embryonic stem cells. Since human cord blood, umbilical cord, placenta and amnion are normally discarded at birth, they provide an easily accessible alternative source of stem cells. We review the potential and current status of the use of adult stem cells derived from the placenta or umbilical cord in therapeutic and toxicological applications.« less

  5. [Characterization of stem cells derived from the neonatal auditory sensory epithelium].

    PubMed

    Diensthuber, M; Heller, S

    2010-11-01

    In contrast to regenerating hair cell-bearing organs of nonmammalian vertebrates the adult mammalian organ of Corti appears to have lost its ability to maintain stem cells. The result is a lack of regenerative ability and irreversible hearing loss following auditory hair cell death. Unexpectedly, the neonatal auditory sensory epithelium has recently been shown to harbor cells with stem cell features. The origin of these cells within the cochlea's sensory epithelium is unknown. We applied a modified neurosphere assay to identify stem cells within distinct subregions of the neonatal mouse auditory sensory epithelium. Sphere cells were characterized by multiple markers and morphologic techniques. Our data reveal that both the greater and the lesser epithelial ridge contribute to the sphere-forming stem cell population derived from the auditory sensory epithelium. These self-renewing sphere cells express a variety of markers for neural and otic progenitor cells and mature inner ear cell types. Stem cells can be isolated from specific regions of the auditory sensory epithelium. The distinct features of these cells imply a potential application in the development of a cell replacement therapy to regenerate the damaged sensory epithelium.

  6. Autologous Pluripotent Stem Cell-Derived β-Like Cells for Diabetes Cellular Therapy.

    PubMed

    Millman, Jeffrey R; Pagliuca, Felicia W

    2017-05-01

    Development of stem cell technologies for cell replacement therapy has progressed rapidly in recent years. Diabetes has long been seen as one of the first applications for stem cell-derived cells because of the loss of only a single cell type-the insulin-producing β-cell. Recent reports have detailed strategies that overcome prior hurdles to generate functional β-like cells from human pluripotent stem cells in vitro, including from human induced pluripotent stem cells (hiPSCs). Even with this accomplishment, addressing immunological barriers to transplantation remains a major challenge for the field. The development of clinically relevant hiPSC derivation methods from patients and demonstration that these cells can be differentiated into β-like cells presents a new opportunity to treat diabetes without immunosuppression or immunoprotective encapsulation or with only targeted protection from autoimmunity. This review focuses on the current status in generating and transplanting autologous β-cells for diabetes cell therapy, highlighting the unique advantages and challenges of this approach. © 2017 by the American Diabetes Association.

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

    PubMed

    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.

  8. [Embryonic stem cells - a scientific by-product of the assisted reproduction technology?].

    PubMed

    Sterthaus, Oliver; Zhang, Hong; De Geyter, Christian

    2009-12-01

    The differentiation potential of embryonic stem (ES) cells seems to be higher when compared to adult stem cells, which mainly differentiate into certain tissue types only. ES cells have the potential to play an important role in regenerative medicine as demonstrated with murine ES cells. However, with human embryonic stem cells (hESC) several obstacles still have to be overcome, when these are to be used in clinical applications. The expansion of hESC, safety issues as well as the immune-tolerance after transplantation are all problems that still have to be solved. Since 2005 the derivation of hESC lines from super-numerous embryos has become permitted in Switzerland, albeit under strictly restrictive guidelines. In 2008 the Basler hESC laboratory was successful in derivating the first hESC line with a normal chromosome complement in Switzerland (CHES2). Now, new applications allow the personalized establishment of immune-tolerant stem cells, which lead to the replacement of therapeutic cloning by induced pluripotent stem cells (iPS).

  9. Stem Cells and Calcium Signaling

    PubMed Central

    Tonelli, Fernanda M.P.; Santos, Anderson K.; Gomes, Dawidson A.; da Silva, Saulo L.; Gomes, Katia N.; Ladeira, Luiz O.

    2014-01-01

    The increasing interest in stem cell research is linked to the promise of developing treatments for many lifethreatening, debilitating diseases, and for cell replacement therapies. However, performing these therapeutic innovations with safety will only be possible when an accurate knowledge about the molecular signals that promote the desired cell fate is reached. Among these signals are transient changes in intracellular Ca2+ concentration [Ca2+]i. Acting as an intracellular messenger, Ca2+ has a key role in cell signaling pathways in various differentiation stages of stem cells. The aim of this chapter is to present a broad overview of various moments in which Ca2+-mediated signaling is essential for the maintenance of stem cells and for promoting their development and differentiation, also focusing on their therapeutic potential. PMID:22453975

  10. Concise Review: Pluripotent Stem Cell-Based Regenerative Applications for Failing β-Cell Function

    PubMed Central

    Holditch, Sara J.; Terzic, Andre

    2014-01-01

    Diabetes engenders the loss of pancreatic β-cell mass and/or function, resulting in insulin deficiency relative to the metabolic needs of the body. Diabetic care has traditionally relied on pharmacotherapy, exemplified by insulin replacement to target peripheral actions of the hormone. With growing understanding of the pathogenesis of diabetic disease, alternative approaches aiming at repair and restoration of failing β-cell function are increasingly considered as complements to current diabetes therapy regimens. To this end, emphasis is placed on transplantation of exogenous pancreas/islets or artificial islets, enhanced proliferation and maturation of endogenous β cells, prevention of β-cell loss, or fortified renewal of β-like-cell populations from stem cell pools and non-β-cell sources. In light of emerging clinical experiences with human embryonic stem cells and approval of the first in-human trial with induced pluripotent stem cells, in this study we highlight advances in β-cell regeneration strategies with a focus on pluripotent stem cell platforms in the context of translational applications. PMID:24646490

  11. Plasticity within stem cell hierarchies in mammalian epithelia.

    PubMed

    Tetteh, Paul W; Farin, Henner F; Clevers, Hans

    2015-02-01

    Tissue homeostasis and regeneration are fueled by resident stem cells that have the capacity to self-renew, and to generate all the differentiated cell types that characterize a particular tissue. Classical models of such cellular hierarchies propose that commitment and differentiation occur unidirectionally, with the arrows 'pointing away' from the stem cell. Recent studies, all based on genetic lineage tracing, describe various strategies employed by epithelial stem cell hierarchies to replace damaged or lost cells. While transdifferentiation from one tissue type into another ('metaplasia') appears to be generally forbidden in nonpathological contexts, plasticity within an individual tissue stem cell hierarchy may be much more common than previously appreciated. In this review, we discuss recent examples of such plasticity in selected mammalian epithelia, highlighting the different modes of regeneration and their implications for our understanding of cellular hierarchy and tissue self-renewal. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Regenerative Endodontics in light of the stem cell paradigm

    PubMed Central

    Rosa, Vinicius; Botero, Tatiana M.; Nör, Jacques E.

    2013-01-01

    Stem cells play a critical role in development and in tissue regeneration. The dental pulp contains a small sub-population of stem cells that are involved in the response of the pulp to caries progression. Specifically, stem cells replace odontoblasts that have undergone cell death as a consequence of the cariogenic challenge. Stem cells also secrete factors that have the potential to enhance pulp vascularization and provide the oxygen and nutrients required for the dentinogenic response that is typically observed in teeth with deep caries. However, the same angiogenic factors that are required for dentin regeneration may ultimately contribute to the demise of the pulp by enhancing vascular permeability and interstitial pressure. Recent studies focused on the biology of dental pulp stem cells revealed that the multipotency and angiogenic capacity of these cells could be exploited therapeutically in dental pulp tissue engineering. Collectively, these findings suggest new treatment paradigms in the field of Endodontics. The goal of this review is to discuss the potential impact of dental pulp stem cells to Regenerative Endodontics. PMID:21726222

  13. A novel role for bioactive lipids in stem cell mobilization during cardiac ischemia

    PubMed Central

    Nagareddy, Prabhakara R.; Asfour, Ahmed; Klyachkin, Yuri M.; Abdel-Latif, Ahmed

    2014-01-01

    Despite major advances in pharmacological and reperfusion therapies, regenerating and/or replacing the infarcted myocardial tissue is an enormous challenge and therefore ischemic heart disease (IHD) remains a major cause of mortality and morbidity worldwide. Adult bone marrow is home for a variety of hematopoietic and non-hematopoietic stem cells including a small subset of primitive cells that carry a promising regenerative potential. It is now well established that myocardial ischemia (MI) induces mobilization of bone marrow-derived cells including differentiated lineage as well as undifferentiated stem cells. While the numbers of stem cells carrying pluripotent features among the mobilized stem cells is small, their regenerative capacity appears immense. Therapies aimed at selective mobilization of these pluripotent stem cells during myocardial ischemia have a promising potential to regenerate the injured myocardium. Emerging evidence suggest that bioactive sphingolipids such as sphingosine-1 phosphate and ceramide-1 phosphate hold a great promise in selective mobilization of pluripotent stem cells to the infarcted region during MI. This review highlights the recent advances in the mechanisms of stem cell mobilization and provides newer evidence in support of bioactive lipids as potential therapeutic agents in the treatment of ischemic heart disease. PMID:24318213

  14. [Stem cells therapy in amyotrophic lateral sclerosis treatment. A critical view].

    PubMed

    Soler, Bernardita; Fadic, Ricardo; von Bernhardi, Rommy

    2011-04-01

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease. At present, there are not curative therapies for ALS. Pathogenic and progression mechanisms suggest the existence of oxidative stress, abnormal intracellular protein aggregation, mitochondrial dysfunction, axonal transport impairment, impairment of trophic support, altered glial cell function, and glutamate excitoxicity. To evaluate therapeutic results with adult stem cell for ALS treatment. Stem cells represent a potential therapeutic strategy, because their biological mechanisms could act on several of the pathogenic mechanisms proposed for ALS. Bone marrow mesenchymal stem cells are especially interesting among adult stem cells. Mesenchymal stem cells can differentiate in all central nervous system cells and potentially replace them. Furthermore, they have immunomodulatory effects, secreting, especially in neuroinflammatory environments, neurotrophic and antiinflammatory factors. Studies in murine models of ALS show decrease of inflammation and disease progression, and increase on animal highly heterogeneous, suggest that mesenchymal stem cells transplant in ALS appears to be safe. However, they fail showing clinical improvement of patients. Additional preclinical studies are necessary to refine this therapeutic approach, to assess long term survival and differentiation of mesenchymal stem cells, dosing, biological activity and safety should be conducted before any planning further human testing occurs.

  15. Predatory stem cells in the non-zebrafish chordate, Botryllus schlosseri.

    PubMed

    Laird, Diana J; De Tomaso, Anthony W

    2005-01-01

    Botryllus schlosseri is a primitive marine chordate which provides a new model organism to study stem cell biology for several reasons. First, B. schlosseri is a colonial organism that undergoes continuous and regular asexual development. Botryllus adults regenerate themselves, including all somatic tissues and the germline, every week. Second, under natural conditions the cells responsible can mobilize and transplant between two individuals. Once transplanted, these cells can proliferate, differentiate, and often completely replace the cells of the host in both the germline and/or somatic tissues. These processes are called germ cell parasitism (gcp), or somatic cell parasitism (scp), respectively, and we have shown that there are winners and losers in this process, implying that the competitive ability of stem cells is a genetically-determined trait. Fundamental characteristics of stem cell biology, such as self-renewal capacity, homing, or differentiation kinetics must underlie the ability of a stem cell of one genotype to out-compete a stem cell of another genotype, and we are using this system prospectively to isolate the cells responsible and to analyze the molecular mechanisms underlying gcp and scp phenotypes.

  16. Translating the Potential of Stem Cells for Diabetes Mellitus: Challenges and Opportunities.

    PubMed

    Masoud, Muhammad Shareef; Qasim, Muhammad; Ali, Muhammad Umar

    2017-01-01

    Diabetes mellitus, the widely prevalent disease of pancreas, is a metabolic disorder caused by autoimmune destruction of β cells or insulin insufficiency or insulin resistance. Replacement of damaged β cells by cell therapy can mitigate the condition and re-establish normal metabolic control. This has opened up new horizons for research, such as stem cells, cellular reprogramming and β cell regeneration. The goal of the study was to summarize the available literature on the use of stem cells for the regeneration of pancreatic β cells and treatment of diabetes mellitus. Stem cells are exceptional having the potential to self renew and differentiate in many lineages. Stem cells hold tremendous potential to regenerate β cells and treat diabetes mellitus but many milestones on the way are yet to be achieved. But researchers do believe that stem cells and regenerative medicines will be widely used in clinical practices and possibly new effective methodology would be designed for even cure, mitigate and reduce the social burden of diabetes mellitus. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  17. White paper on guidelines concerning enteric nervous system stem cell therapy for enteric neuropathies⋆

    PubMed Central

    Burns, Alan J.; Goldstein, Allan M.; Newgreen, Donald F.; Stamp, Lincon; Schäfer, Karl-Herbert; Metzger, Marco; Hotta, Ryo; Young, Heather M.; Andrews, Peter W.; Thapar, Nikhil; Belkind-Gerson, Jaime; Bondurand, Nadege; Bornstein, Joel C.; Chan, Wood Yee; Cheah, Kathryn; Gershon, Michael D.; Heuckeroth, Robert O.; Hofstra, Robert M.W.; Just, Lothar; Kapur, Raj P.; King, Sebastian K.; McCann, Conor J.; Nagy, Nandor; Ngan, Elly; Obermayr, Florian; Pachnis, Vassilis; Pasricha, Pankaj J.; Sham, Mai Har; Tam, Paul; Berghe, Pieter Vanden

    2016-01-01

    Over the last 20 years, there has been increasing focus on the development of novel stem cell based therapies for the treatment of disorders and diseases affecting the enteric nervous system (ENS) of the gastrointestinal tract (so-called enteric neuropathies). Here, the idea is that ENS progenitor/stem cells could be transplanted into the gut wall to replace the damaged or absent neurons and glia of the ENS. This White Paper sets out experts’ views on the commonly used methods and approaches to identify, isolate, purify, expand and optimize ENS stem cells, transplant them into the bowel, and assess transplant success, including restoration of gut function. We also highlight obstacles that must be overcome in order to progress from successful preclinical studies in animal models to ENS stem cell therapies in the clinic. PMID:27059883

  18. Towards consistent generation of pancreatic lineage progenitors from human pluripotent stem cells.

    PubMed

    Rostovskaya, Maria; Bredenkamp, Nicholas; Smith, Austin

    2015-10-19

    Human pluripotent stem cells can in principle be used as a source of any differentiated cell type for disease modelling, drug screening, toxicology testing or cell replacement therapy. Type I diabetes is considered a major target for stem cell applications due to the shortage of primary human beta cells. Several protocols have been reported for generating pancreatic progenitors by in vitro differentiation of human pluripotent stem cells. Here we first assessed one of these protocols on a panel of pluripotent stem cell lines for capacity to engender glucose sensitive insulin-producing cells after engraftment in immunocompromised mice. We observed variable outcomes with only one cell line showing a low level of glucose response. We, therefore, undertook a systematic comparison of different methods for inducing definitive endoderm and subsequently pancreatic differentiation. Of several protocols tested, we identified a combined approach that robustly generated pancreatic progenitors in vitro from both embryo-derived and induced pluripotent stem cells. These findings suggest that, although there are intrinsic differences in lineage specification propensity between pluripotent stem cell lines, optimal differentiation procedures may consistently direct a substantial fraction of cells into pancreatic specification. © 2015 The Authors.

  19. The Emerging Cell Biology of Thyroid Stem Cells

    PubMed Central

    Latif, Rauf; Minsky, Noga C.; Ma, Risheng

    2011-01-01

    Context: Stem cells are undifferentiated cells with the property of self-renewal and give rise to highly specialized cells under appropriate local conditions. The use of stem cells in regenerative medicine holds great promise for the treatment of many diseases, including those of the thyroid gland. Evidence Acquisition: This review focuses on the progress that has been made in thyroid stem cell research including an overview of cellular and molecular events (most of which were drawn from the period 1990–2011) and discusses the remaining problems encountered in their differentiation. Evidence Synthesis: Protocols for the in vitro differentiation of embryonic stem cells, based on normal developmental processes, have generated thyroid-like cells but without full thyrocyte function. However, agents have been identified, including activin A, insulin, and IGF-I, which are able to stimulate the generation of thyroid-like cells in vitro. In addition, thyroid stem/progenitor cells have been identified within the normal thyroid gland and within thyroid cancers. Conclusions: Advances in thyroid stem cell biology are providing not only insight into thyroid development but may offer therapeutic potential in thyroid cancer and future thyroid cell replacement therapy. PMID:21778219

  20. Stem cell therapy emerging as the key player in treating type 1 diabetes mellitus.

    PubMed

    Vanikar, Aruna V; Trivedi, Hargovind L; Thakkar, Umang G

    2016-09-01

    Type 1 diabetes mellitus (T1DM) is an autoimmune disease causing progressive destruction of pancreatic β cells, ultimately resulting in loss of insulin secretion producing hyperglycemia usually affecting children. Replacement of damaged β cells by cell therapy can treat it. Currently available strategies are insulin replacement and islet/pancreas transplantation. Unfortunately these offer rescue for variable duration due to development of autoantibodies. For pancreas/islet transplantation a deceased donor is required and various shortfalls of treatment include quantum, cumbersome technique, immune rejection and limited availability of donors. Stem cell therapy with assistance of cellular reprogramming and β-cell regeneration can open up new therapeutic modalities. The present review describes the history and current knowledge of T1DM, evolution of cell therapies and different cellular therapies to cure this condition. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  1. Prolonged survival of transplanted stem cells after ischaemic injury via the slow release of pro-survival peptides from a collagen matrix

    PubMed Central

    Lee, Andrew S.; Inayathullah, Mohammed; Lijkwan, Maarten A.; Zhao, Xin; Sun, Wenchao; Park, Sujin; Hong, Wan Xing; Parekh, Mansi B.; Malkovskiy, Andrey V.; Lau, Edward; Qin, Xulei; Pothineni, Venkata Raveendra; Sanchez-Freire, Verónica; Zhang, Wendy Y.; Kooreman, Nigel G.; Ebert, Antje D.; Chan, Charles K. F.; Nguyen, Patricia K.; Rajadas, Jayakumar; Wu, Joseph C.

    2018-01-01

    Stem-cell-based therapies hold considerable promise for regenerative medicine. However, acute donor-cell death within several weeks after cell delivery remains a critical hurdle for clinical translation. Co-transplantation of stem cells with pro-survival factors can improve cell engraftment, but this strategy has been hampered by the typically short half-lives of the factors and by the use of Matrigel and other scaffolds that are not chemically defined. Here, we report a collagen–dendrimer biomaterial crosslinked with pro-survival peptide analogues that adheres to the extracellular matrix and slowly releases the peptides, significantly prolonging stem cell survival in mouse models of ischaemic injury. The biomaterial can serve as a generic delivery system to improve functional outcomes in cell-replacement therapy. PMID:29721363

  2. Micro-Computed Tomography Detection of Gold Nanoparticle-Labelled Mesenchymal Stem Cells in the Rat Subretinal Layer.

    PubMed

    Mok, Pooi Ling; Leow, Sue Ngein; Koh, Avin Ee-Hwan; Mohd Nizam, Hairul Harun; Ding, Suet Lee Shirley; Luu, Chi; Ruhaslizan, Raduan; Wong, Hon Seng; Halim, Wan Haslina Wan Abdul; Ng, Min Hwei; Idrus, Ruszymah Binti Hj; Chowdhury, Shiplu Roy; Bastion, Catherine Mae-Lynn; Subbiah, Suresh Kumar; Higuchi, Akon; Alarfaj, Abdullah A; Then, Kong Yong

    2017-02-08

    Mesenchymal stem cells are widely used in many pre-clinical and clinical settings. Despite advances in molecular technology; the migration and homing activities of these cells in in vivo systems are not well understood. Labelling mesenchymal stem cells with gold nanoparticles has no cytotoxic effect and may offer suitable indications for stem cell tracking. Here, we report a simple protocol to label mesenchymal stem cells using 80 nm gold nanoparticles. Once the cells and particles were incubated together for 24 h, the labelled products were injected into the rat subretinal layer. Micro-computed tomography was then conducted on the 15th and 30th day post-injection to track the movement of these cells, as visualized by an area of hyperdensity from the coronal section images of the rat head. In addition, we confirmed the cellular uptake of the gold nanoparticles by the mesenchymal stem cells using transmission electron microscopy. As opposed to other methods, the current protocol provides a simple, less labour-intensive and more efficient labelling mechanism for real-time cell tracking. Finally, we discuss the potential manipulations of gold nanoparticles in stem cells for cell replacement and cancer therapy in ocular disorders or diseases.

  3. Micro-Computed Tomography Detection of Gold Nanoparticle-Labelled Mesenchymal Stem Cells in the Rat Subretinal Layer

    PubMed Central

    Mok, Pooi Ling; Leow, Sue Ngein; Koh, Avin Ee-Hwan; Mohd Nizam, Hairul Harun; Ding, Suet Lee Shirley; Luu, Chi; Ruhaslizan, Raduan; Wong, Hon Seng; Halim, Wan Haslina Wan Abdul; Ng, Min Hwei; Idrus, Ruszymah Binti Hj.; Chowdhury, Shiplu Roy; Bastion, Catherine Mae-Lynn; Subbiah, Suresh Kumar; Higuchi, Akon; Alarfaj, Abdullah A.; Then, Kong Yong

    2017-01-01

    Mesenchymal stem cells are widely used in many pre-clinical and clinical settings. Despite advances in molecular technology; the migration and homing activities of these cells in in vivo systems are not well understood. Labelling mesenchymal stem cells with gold nanoparticles has no cytotoxic effect and may offer suitable indications for stem cell tracking. Here, we report a simple protocol to label mesenchymal stem cells using 80 nm gold nanoparticles. Once the cells and particles were incubated together for 24 h, the labelled products were injected into the rat subretinal layer. Micro-computed tomography was then conducted on the 15th and 30th day post-injection to track the movement of these cells, as visualized by an area of hyperdensity from the coronal section images of the rat head. In addition, we confirmed the cellular uptake of the gold nanoparticles by the mesenchymal stem cells using transmission electron microscopy. As opposed to other methods, the current protocol provides a simple, less labour-intensive and more efficient labelling mechanism for real-time cell tracking. Finally, we discuss the potential manipulations of gold nanoparticles in stem cells for cell replacement and cancer therapy in ocular disorders or diseases. PMID:28208719

  4. Stem cells for cardiac repair: an introduction

    PubMed Central

    du Pré, Bastiaan C; Doevendans, Pieter A; van Laake, Linda W

    2013-01-01

    Cardiovascular disease is a major cause of morbidity and mortality throughout the world. Most cardiovascular diseases, such as ischemic heart disease and cardiomyopathy, are associated with loss of functional cardiomyocytes. Unfortunately, the heart has a limited regenerative capacity and is not able to replace these cardiomyocytes once lost. In recent years, stem cells have been put forward as a potential source for cardiac regeneration. Pre-clinical studies that use stem cell-derived cardiac cells show promising results. The mechanisms, though, are not well understood, results have been variable, sometimes transient in the long term, and often without a mechanistic explanation. There are still several major hurdles to be taken. Stem cell-derived cardiac cells should resemble original cardiac cell types and be able to integrate in the damaged heart. Integration requires administration of stem cell-derived cardiac cells at the right time using the right mode of delivery. Once delivered, transplanted cells need vascularization, electrophysiological coupling with the injured heart, and prevention of immunological rejection. Finally, stem cell therapy needs to be safe, reproducible, and affordable. In this review, we will give an introduction to the principles of stem cell based cardiac repair. PMID:23888179

  5. Restoration of heart functions using human embryonic stem cells derived heart muscle cells.

    PubMed

    Gepstein, Lior; Kehat, Izhak

    2005-02-01

    Extract: Recent advances in molecular and cellular biology and specifically in the areas of stem cell biology and tissue engineering have paved the way for the development of a new field in biomedicine, regenerative medicine. This exciting approach seeks to develop new biological solutions, using the mobilization of endogenous stem cells or delivery of exogenous cells to replace or modify the function of diseased, absent, or malfunctioning tissue. The adult heart represents an attractive candidate for these emerging technologies, since adult cardiomyocytes have limited regenerative capacity. Thus, any significant heart cell loss or dysfunction, such as occurs during heart attack, is mostly irreversible and may lead to the development of progressive heart failure, one of the leading causes of world-wide morbidity and mortality. Similarly, dysfunction of the specialized electrical conduction system within the heart may result in inefficient rhythm initiation or impulse conduction, leading to significant slowing of the heart rate, usually requiring the implantation of a permanent electronic pacemaker. Replacement of the dysfunctional myocardium (heart muscle) by implantation of external heart muscle cells is emerging as a novel paradigm for restoration of the myocardial electromechanical properties, but has been significantly hampered by the paucity of cell sources for human heart cells and by the relatively limited evidence for functional integration between grafted and host cells. The recently described human embryonic stem cell (hESC) lines may provide a possible solution for the aforementioned cell sourcing problem.

  6. A natural stem cell therapy? How novel findings and biotechnology clarify the ethics of stem cell research

    PubMed Central

    Patel, P

    2006-01-01

    The natural replacement of damaged cells by stem cells occurs actively and often in adult tissues, especially rapidly dividing cells such as blood cells. An exciting case in Boston, however, posits a kind of natural stem cell therapy provided to a mother by her fetus—long after the fetus is born. Because there is a profound lack of medical intervention, this therapy seems natural enough and is unlikely to be morally suspect. Nevertheless, we feel morally uncertain when we consider giving this type of therapy to patients who would not naturally receive it. Much has been written about the ethics of stem cell research and therapy; this paper will focus on how recent advances in biotechnology and biological understandings of development narrow the debate. Here, the author briefly reviews current stem cell research practices, revisits the natural stem cell therapy case for moral evaluation, and ultimately demonstrates the importance of permissible stem cell research and therapy, even absent an agreement about the definition of when embryonic life begins. Although one promising technology, blighted ovum utilisation, uses fertilised but developmentally bankrupt eggs, it is argued that utilisation of unfertilised eggs to derive totipotent stem cells obviates the moral debate over when life begins. There are two existing technologies that fulfil this criterion: somatic cell nuclear transfer and parthenogenic stem cell derivation. Although these technologies are far from therapeutic, concerns over the morality of embryonic stem cell derivation should not hinder their advancement. PMID:16574879

  7. Delivery of Differentiation Factors by Mesoporous Silica Particles Assists Advanced Differentiation of Transplanted Murine Embryonic Stem Cells

    PubMed Central

    Kozhevnikova, Mariya; König, Niclas; Zhou, Chunfang; Leao, Richardson; Knöpfel, Thomas; Pankratova, Stanislava; Trolle, Carl; Berezin, Vladimir; Bock, Elisabeth; Aldskogius, Håkan

    2013-01-01

    Stem cell transplantation holds great hope for the replacement of damaged cells in the nervous system. However, poor long-term survival after transplantation and insufficiently robust differentiation of stem cells into specialized cell types in vivo remain major obstacles for clinical application. Here, we report the development of a novel technological approach for the local delivery of exogenous trophic factor mimetics to transplanted cells using specifically designed silica nanoporous particles. We demonstrated that delivering Cintrofin and Gliafin, established peptide mimetics of the ciliary neurotrophic factor and glial cell line-derived neurotrophic factor, respectively, with these particles enabled not only robust functional differentiation of motor neurons from transplanted embryonic stem cells but also their long-term survival in vivo. We propose that the delivery of growth factors by mesoporous nanoparticles is a potentially versatile and widely applicable strategy for efficient differentiation and functional integration of stem cell derivatives upon transplantation. PMID:24089415

  8. Quantification of Crypt and Stem Cell Evolution in the Normal and Neoplastic Human Colon

    PubMed Central

    Baker, Ann-Marie; Cereser, Biancastella; Melton, Samuel; Fletcher, Alexander G.; Rodriguez-Justo, Manuel; Tadrous, Paul J.; Humphries, Adam; Elia, George; McDonald, Stuart A.C.; Wright, Nicholas A.; Simons, Benjamin D.; Jansen, Marnix; Graham, Trevor A.

    2014-01-01

    Summary Human intestinal stem cell and crypt dynamics remain poorly characterized because transgenic lineage-tracing methods are impractical in humans. Here, we have circumvented this problem by quantitatively using somatic mtDNA mutations to trace clonal lineages. By analyzing clonal imprints on the walls of colonic crypts, we show that human intestinal stem cells conform to one-dimensional neutral drift dynamics with a “functional” stem cell number of five to six in both normal patients and individuals with familial adenomatous polyposis (germline APC−/+). Furthermore, we show that, in adenomatous crypts (APC−/−), there is a proportionate increase in both functional stem cell number and the loss/replacement rate. Finally, by analyzing fields of mtDNA mutant crypts, we show that a normal colon crypt divides around once every 30–40 years, and the division rate is increased in adenomas by at least an order of magnitude. These data provide in vivo quantification of human intestinal stem cell and crypt dynamics. PMID:25127143

  9. Induced pluripotent stem cells for the treatment of stroke: the potential and the pitfalls.

    PubMed

    Yu, Fenggang; Li, Yingying; Morshead, Cindi M

    2013-09-01

    The extraordinary discovery of induced pluripotent stem cells (iPSCs) has led to the very real possibility that patient-specific cell therapy can be realized. The potential to develop cell replacement therapies outside the ethical and legal limitations, has initiated a new era of hope for regenerative strategies to treat human neurological disease including stroke. In this article, we will review and compare the current approaches to derive iPSCs from different somatic cells, and the induction into neuronal phenotypes, considering the advantages and disadvantages to the methodologies of derivation. We will highlight the work relating to the use of iPSC-based therapies in models of stroke and their potential use in clinical trials. Finally, we will consider future directions and areas of exploration which may promote the realization of iPSC-based cell replacement strategies for the treatment of stroke.

  10. Genetic engineered molecular imaging probes for applications in cell therapy: emphasis on MRI approach

    PubMed Central

    Cho, In K; Wang, Silun; Mao, Hui; Chan, Anthony WS

    2016-01-01

    Recent advances in stem cell-based regenerative medicine, cell replacement therapy, and genome editing technologies (i.e. CRISPR-Cas 9) have sparked great interest in in vivo cell monitoring. Molecular imaging promises a unique approach to noninvasively monitor cellular and molecular phenomena, including cell survival, migration, proliferation, and even differentiation at the whole organismal level. Several imaging modalities and strategies have been explored for monitoring cell grafts in vivo. We begin this review with an introduction describing the progress in stem cell technology, with a perspective toward cell replacement therapy. The importance of molecular imaging in reporting and assessing the status of cell grafts and their relation to the local microenvironment is highlighted since the current knowledge gap is one of the major obstacles in clinical translation of stem cell therapy. Based on currently available imaging techniques, we provide a brief discussion on the pros and cons of each imaging modality used for monitoring cell grafts with particular emphasis on magnetic resonance imaging (MRI) and the reporter gene approach. Finally, we conclude with a comprehensive discussion of future directions of applying molecular imaging in regenerative medicine to emphasize further the importance of correlating cell graft conditions and clinical outcomes to advance regenerative medicine. PMID:27766183

  11. Therapeutic Potential, Challenges and Future Perspective of Cancer Stem Cells in Translational Oncology: A Critical Review.

    PubMed

    Shukla, Gaurav; Khera, Harvinder Kour; Srivastava, Amit Kumar; Khare, Piush; Patidar, Rahul; Saxena, Rajiv

    2017-01-01

    Stem cell research is a rapidly developing field that offers effective treatment for a variety of malignant and non-malignant diseases. Stem cell is a regenerative medicine associated with the replacement, repair, and restoration of injured tissue. Stem cell research is a promising field having maximum therapeutic potential. Cancer stem cells (CSCs) are the cells within the tumor that posses capacity of selfrenewal and have a root cause for the failure of traditional therapies leading to re-occurrence of cancer. CSCs have been identified in blood, breast, brain, and colon cancer. Traditional therapies target only fast growing tumor mass, but not slow-dividing cancer stem cells. It has been shown that embryonic pathways such as Wnt, Hedgehog and Notch, control self-renewal capacity and involved in cancer stem cell maintenance. Targeting of these pathways may be effective in eradicating cancer stem cells and preventing chemotherapy and radiotherapy resistance. Targeting CSCs has become one of the most effective approaches to improve the cancer survival by eradicating the main root cause of cancer. The present review will address, in brief, the importance of cancer stem cells in targeting cancer as better and effective treatment along with a concluding outlook on the scope and challenges in the implication of cancer stem cells in translational oncology. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  12. Concise Review: Bioprinting of Stem Cells for Transplantable Tissue Fabrication.

    PubMed

    Leberfinger, Ashley N; Ravnic, Dino J; Dhawan, Aman; Ozbolat, Ibrahim T

    2017-10-01

    Bioprinting is a quickly progressing technology, which holds the potential to generate replacement tissues and organs. Stem cells offer several advantages over differentiated cells for use as starting materials, including the potential for autologous tissue and differentiation into multiple cell lines. The three most commonly used stem cells are embryonic, induced pluripotent, and adult stem cells. Cells are combined with various natural and synthetic materials to form bioinks, which are used to fabricate scaffold-based or scaffold-free constructs. Computer aided design technology is combined with various bioprinting modalities including droplet-, extrusion-, or laser-based bioprinting to create tissue constructs. Each bioink and modality has its own advantages and disadvantages. Various materials and techniques are combined to maximize the benefits. Researchers have been successful in bioprinting cartilage, bone, cardiac, nervous, liver, and vascular tissues. However, a major limitation to clinical translation is building large-scale vascularized constructs. Many challenges must be overcome before this technology is used routinely in a clinical setting. Stem Cells Translational Medicine 2017;6:1940-1948. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  13. Regenerative Medicine for the Heart: Perspectives on Stem-Cell Therapy

    PubMed Central

    Cho, Gun-Sik; Fernandez, Laviel

    2014-01-01

    Abstract Significance: Despite decades of progress in cardiovascular biology and medicine, heart disease remains the leading cause of death, and there is no cure for the failing heart. Since heart failure is mostly caused by loss or dysfunction of cardiomyocytes (CMs), replacing dead or damaged CMs with new CMs might be an ideal way to reverse the disease. However, the adult heart is composed mainly of terminally differentiated CMs that have no significant self-regeneration capacity. Recent Advances: Stem cells have tremendous regenerative potential and, thus, current cardiac regenerative research has focused on developing stem cell sources to repair damaged myocardium. Critical Issues: In this review, we examine the potential sources of cells that could be used for heart therapies, including embryonic stem cells and induced pluripotent stem cells, as well as alternative methods for activating the endogenous regenerative mechanisms of the heart via transdifferentiation and cell reprogramming. We also discuss the current state of knowledge of cell purification, delivery, and retention. Future Directions: Efforts are underway to improve the current stem cell strategies and methodologies, which will accelerate the development of innovative stem-cell therapies for heart regeneration. Antioxid. Redox Signal. 21, 2018–2031. PMID:25133793

  14. Suspension culture of pluripotent stem cells: effect of shear on stem cell fate.

    PubMed

    Keller, Kevin C; Rodrigues, Beatriz; zur Nieden, Nicole I

    2014-01-01

    Despite significant promise, the routine usage of suspension cell culture to manufacture stem cell-derived differentiated cells has progressed slowly. Suspension culture is an innovative way of either expanding or differentiating cells and sometimes both are combined into a single bioprocess. Its advantages over static 2D culturing include a homogeneous and controllable culture environment and producing a large quantity of cells in a fraction of time. This feature makes suspension cell culture ideal for use in stem cell research and eventually ideal in the large-scale production of differentiated cells for regenerative medicine. Because of their tremendous differentiation capacities and unlimited growth properties, pluripotent stem cells (PSCs) in particular are considered potential sources for future cell-replacement therapies. Currently, expansion of PSCs is accomplished in 2D, which only permits a limited amount of cell growth per culture flask before cells need to be passaged. However, before stem cells can be applied clinically, several aspects of their expansion, such as directed growth, but also differentiation, need to be better controlled. This review will summarize recent advantages in suspension culture of PSCs, while at the same time highlighting current challenges.

  15. Generation of diverse neural cell types through direct conversion

    PubMed Central

    Petersen, Gayle F; Strappe, Padraig M

    2016-01-01

    A characteristic of neurological disorders is the loss of critical populations of cells that the body is unable to replace, thus there has been much interest in identifying methods of generating clinically relevant numbers of cells to replace those that have been damaged or lost. The process of neural direct conversion, in which cells of one lineage are converted into cells of a neural lineage without first inducing pluripotency, shows great potential, with evidence of the generation of a range of functional neural cell types both in vitro and in vivo, through viral and non-viral delivery of exogenous factors, as well as chemical induction methods. Induced neural cells have been proposed as an attractive alternative to neural cells derived from embryonic or induced pluripotent stem cells, with prospective roles in the investigation of neurological disorders, including neurodegenerative disease modelling, drug screening, and cellular replacement for regenerative medicine applications, however further investigations into improving the efficacy and safety of these methods need to be performed before neural direct conversion becomes a clinically viable option. In this review, we describe the generation of diverse neural cell types via direct conversion of somatic cells, with comparison against stem cell-based approaches, as well as discussion of their potential research and clinical applications. PMID:26981169

  16. Expanded Stem Cells, Stromal-Vascular Fraction, and Platelet-Rich Plasma Enriched Fat: Comparing Results of Different Facial Rejuvenation Approaches in a Clinical Trial

    PubMed Central

    Rigotti, Gino; Charles-de-Sá, Luiz; Gontijo-de-Amorim, Natale Ferreira; Takiya, Christina Maeda; Amable, Paola Romina; Borojevic, Radovan; Benati, Donatella; Bernardi, Paolo; Sbarbati, Andrea

    2016-01-01

    Background In a previous study, the authors demonstrated that treatment with expanded adipose-derived stem cells or stromal vascular fraction (SVF)-enriched fat modify the pattern of the dermis in human beings, representing a skin rejuvenation effect. Considering that expanded stem cells require a cell factor, the authors wanted to assess similar results by replacing them with platelet-rich plasma (PRP), which is easier to obtain and for which an empirical regenerative effect has been already described. Objectives To determine if PRP injection could replace the cutaneous regenerative effect of adipose-derived stem cells. Methods This study was performed in 13 patients who were candidates for facelift. The patients underwent sampling of fat by liposuction from the abdomen and submitted to one of three protocols: injection of SVF-enriched fat or expanded adipose-derived stem cells or fat plus PRP in the preauricular areas. Fragments of skin were removed before and 3 months after treatment and analyzed by optical and electron microscopy. Results The use of fat plus PRP led to the presence of more pronounced inflammatory infiltrates and a greater vascular reactivity, increasing in vascular permeability and a certain reactivity of the nervous component. The addition of PRP did not improve the regenerative effect. Conclusion The use of PRP did not have significant advantages in skin rejuvenation over the use of expanded adipose-derived stem cells or SVF-enriched fat. The effect of increased vascular reactivity may be useful in pathological situations in which an intense angiogenesis is desirable, such as tissular ischemia. Level of Evidence: 4 Therapeutic PMID:26879294

  17. Mesenchymal stem cell therapy in the treatment of osteoarthritis: reparative pathways, safety and efficacy - a review.

    PubMed

    Freitag, Julien; Bates, Dan; Boyd, Richard; Shah, Kiran; Barnard, Adele; Huguenin, Leesa; Tenen, Abi

    2016-05-26

    Osteoarthritis is a leading cause of pain and disability across the world. With an aging population its prevalence is likely to further increase. Current accepted medical treatment strategies are aimed at symptom control rather than disease modification. Surgical options including joint replacement are not without possible significant complications. A growing interest in the area of regenerative medicine, led by an improved understanding of the role of mesenchymal stem cells in tissue homeostasis and repair, has seen recent focused efforts to explore the potential of stem cell therapies in the active management of symptomatic osteoarthritis. Encouragingly, results of pre-clinical and clinical trials have provided initial evidence of efficacy and indicated safety in the therapeutic use of mesenchymal stem cell therapies for the treatment of knee osteoarthritis. This paper explores the pathogenesis of osteoarthritis and how mesenchymal stem cells may play a role in future management strategies of this disabling condition.

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

    NASA Astrophysics Data System (ADS)

    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.

  19. Cells, Scaffolds and Their Interactions in Myocardial Tissue Regeneration.

    PubMed

    Gorabi, Armita Mahdavi; Tafti, Seyed Hossein Ahmadi; Soleimani, Masoud; Panahi, Yunes; Sahebkar, Amirhossein

    2017-08-01

    Cardiac regenerative therapy includes several techniques to repair and replace damaged tissues and organs using cells, biomaterials, molecules, or a combination of these factors. Generation of heart muscle is the most important challenge in this field, although it is well known that new advances in stem cell isolation and culture techniques in bioreactors and synthesis of bioactive materials contribute to the creation of cardiac tissue regeneration in vitro. Some investigations in stem cell biology shows that stem cells are an important source for regeneration of heart muscle cells and blood vessels and can thus clinically contribute to the regeneration of damaged heart tissue. The aim of this review was to explain the principles and challenges of myocardial tissue regeneration with an emphasis on stem cells and scaffolds. J. Cell. Biochem. 118: 2454-2462, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  20. Mesenchymal Stem and Progenitor Cells in Regeneration: Tissue Specificity and Regenerative Potential

    PubMed Central

    Pieber, Thomas Rudolf

    2017-01-01

    It has always been an ambitious goal in medicine to repair or replace morbid tissues for regaining the organ functionality. This challenge has recently gained momentum through considerable progress in understanding the biological concept of the regenerative potential of stem cells. Routine therapeutic procedures are about to shift towards the use of biological and molecular armamentarium. The potential use of embryonic stem cells and invention of induced pluripotent stem cells raised hope for clinical regenerative purposes; however, the use of these interventions for regenerative therapy showed its dark side, as many health concerns and ethical issues arose in terms of using these cells in clinical applications. In this regard, adult stem cells climbed up to the top list of regenerative tools and mesenchymal stem cells (MSC) showed promise for regenerative cell therapy with a rather limited level of risk. MSC have been successfully isolated from various human tissues and they have been shown to offer the possibility to establish novel therapeutic interventions for a variety of hard-to-noncurable diseases. There have been many elegant studies investigating the impact of MSC in regenerative medicine. This review provides compact information on the role of stem cells, in particular, MSC in regeneration. PMID:28286525

  1. Tracking stem cell migration and survival in brain injury: current approaches and future prospects.

    PubMed

    Darkazalli, Ali; Levenson, Cathy W

    2012-10-01

    In recent years, stem cell-mediated therapies have gained considerable ground as potential treatments for a wide variety of brain pathologies including traumatic brain injury, stroke and neurodegenerative diseases. Despite extensive preclinical studies, many of these therapies have not been fully translated into viable clinical approaches. This is partly due to our inability to reliably track and monitor transplanted stem cells longitudinally over long periods of time in vivo. In this review, we discuss the predominant histological cell tracing methodologies, such as immunohistochemistry, and fluorescent cellular dyes and proteins, and compare them to emerging cellular imaging technologies. We show that advances in magnetic resonance imaging (MRI) have resulted in opportunities to use this technology to further our understanding of stem cell characteristics and behaviors in vivo. While MRI may not completely replace conventional cell tracking methods in pre-clinical, mechanistic work, it is clear that it has the potential to function as a powerful diagnostic tool for tracking stem cell migration and survival as well as for evaluating the efficacy of stem cell-mediated therapies.

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

    PubMed

    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.

  3. Ionizing radiation induces senescence and differentiation of human dental pulp stem cells.

    PubMed

    Havelek, R; Soukup, T; Ćmielová, J; Seifrtová, M; Suchánek, J; Vávrová, J; Mokrý, J; Muthná, D; Řezáčová, M

    2013-01-01

    Head and neck cancer is one of the most common cancers in Europe. Many current anti-cancer treatments, including ionizing radiation, induce apoptosis via DNA damage. Unfortunately, such treatments are non-selective to cancer cells and produce similar toxicity in normal cells, including adult stem cells. One of the fundamental properties of an adult stem cell is that it does not have any tissue-specific structures that allow it to perform specialized functions. However, under certain stimuli, unspecialized adult stem cells can give rise to specialized cells to generate replacements for cells that are lost during one's life or due to injury or disease. Nevertheless, specialization of stem cells must be controlled by specific milieu and also initiated at the proper time, making the entire process beneficial for tissue recovery and maintaining it for a long time. In this paper we assess whether irradiated dental pulp stem cells have maintained open their options to mature into specialized cells, or whether they have lost their unspecialized (immature) state following irradiation. Our findings showed radiation-induced premature differentiation of dental pulp stem cells towards odonto-/osteoblast lineages in vitro. Matrix calcification was visualized from Day 6 or Day 9 following irradiation of cells expressing low or high levels of CD146, respectively.

  4. Establishment of autologous embryonic stem cells derived from preantral follicle culture and oocyte parthenogenesis.

    PubMed

    Lee, Seung Tae; Choi, Mun Hwan; Lee, Eun Ju; Gong, Seung Pyo; Jang, Mi; Park, Sang Hyun; Jee, Hyang; Kim, Dae Yong; Han, Jae Yong; Lim, Jeong Mook

    2008-11-01

    To evaluate whether autologous embryonic stem cells can be established without generating clone embryos. Prospective model study. Gamete and stem cell biotechnology laboratory in Seoul National University, Seoul, Korea. F1 hybrid B6D2F1 mice. Preantral follicles were cultured, and oocytes matured in the follicles were parthenogenetically activated. Preimplantation development and stem cell characterization. More intrafollicular oocytes that were retrieved from secondary follicles matured and developed into blastocysts after parthenogenesis than those that were retrieved from primary follicles. Of those 35 blastocysts derived from 193 parthenotes, one line of colony-forming cells was established from the culturing of early secondary follicles. The established cells were positive for embryonic stem cell-specific markers and had normal diploid karyotype and telomerase activity. They differentiated into embryoid bodies in vitro and teratomas in vivo. Inducible differentiation of the established cells into neuronal lineage cells also was possible. Autologous embryonic stem cells can be established by preantral follicle culture and oocyte parthenogenesis. A combined technique of follicle culture and oocyte parthenogenesis that does not use developmentally competent oocytes has the potential to replace somatic cell nuclear transfer for autologous cell therapy.

  5. Genetic strategies to investigate neuronal circuit properties using stem cell-derived neurons

    PubMed Central

    Garcia, Isabella; Kim, Cynthia; Arenkiel, Benjamin R.

    2012-01-01

    The mammalian brain is anatomically and functionally complex, and prone to diverse forms of injury and neuropathology. Scientists have long strived to develop cell replacement therapies to repair damaged and diseased nervous tissue. However, this goal has remained unrealized for various reasons, including nascent knowledge of neuronal development, the inability to track and manipulate transplanted cells within complex neuronal networks, and host graft rejection. Recent advances in embryonic stem cell (ESC) and induced pluripotent stem cell (iPSC) technology, alongside novel genetic strategies to mark and manipulate stem cell-derived neurons, now provide unprecedented opportunities to investigate complex neuronal circuits in both healthy and diseased brains. Here, we review current technologies aimed at generating and manipulating neurons derived from ESCs and iPSCs toward investigation and manipulation of complex neuronal circuits, ultimately leading to the design and development of novel cell-based therapeutic approaches. PMID:23264761

  6. Effects of Intravenous Administration of Human Umbilical Cord Blood Stem Cells in 3-Acetylpyridine-Lesioned Rats

    PubMed Central

    Calatrava-Ferreras, Lucía; Gonzalo-Gobernado, Rafael; Herranz, Antonio S.; Reimers, Diana; Montero Vega, Teresa; Jiménez-Escrig, Adriano; Richart López, Luis Alberto; Bazán, Eulalia

    2012-01-01

    Cerebellar ataxias include a heterogeneous group of infrequent diseases characterized by lack of motor coordination caused by disturbances in the cerebellum and its associated circuits. Current therapies are based on the use of drugs that correct some of the molecular processes involved in their pathogenesis. Although these treatments yielded promising results, there is not yet an effective therapy for these diseases. Cell replacement strategies using human umbilical cord blood mononuclear cells (HuUCBMCs) have emerged as a promising approach for restoration of function in neurodegenerative diseases. The aim of this work was to investigate the potential therapeutic activity of HuUCBMCs in the 3-acetylpyridine (3-AP) rat model of cerebellar ataxia. Intravenous administered HuUCBMCs reached the cerebellum and brain stem of 3-AP ataxic rats. Grafted cells reduced 3-AP-induced neuronal loss promoted the activation of microglia in the brain stem, and prevented the overexpression of GFAP elicited by 3-AP in the cerebellum. In addition, HuUCBMCs upregulated the expression of proteins that are critical for cell survival, such as phospho-Akt and Bcl-2, in the cerebellum and brain stem of 3-AP ataxic rats. As all these effects were accompanied by a temporal but significant improvement in motor coordination, HuUCBMCs grafts can be considered as an effective cell replacement therapy for cerebellar disorders. PMID:23150735

  7. Personalizing Stem Cell Research and Therapy: The Arduous Road Ahead or Missed Opportunity?

    PubMed Central

    Patel, S.A.; King, C.C.; Lim, P.K.; Habiba, U.; Dave, M.; Porecha, R.; Rameshwar, P.

    2010-01-01

    The euphoria of stem cell therapy has diminished, allowing scientists, clinicians and the general public to seriously re-examine how and what types of stem cells would effectively repair damaged tissue, prevent further tissue damage and/or replace lost cells. Importantly, there is a growing recognition that there are substantial person-to-person differences in the outcome of stem cell therapy. Even though the small molecule pharmaceuticals have long remained a primary focus of the personalized medicine research, individualized or targeted use of stem cells to suit a particular individual could help forecast potential failures of the therapy or identify, early on, the individuals who might benefit from stem cell interventions. This would however demand collaboration among several specialties such as pharmacology, immunology, genomics and transplantation medicine. Such transdisciplinary work could also inform how best to achieve efficient and predictable stem cell migration to sites of tissue damage, thereby facilitating tissue repair. This paper discusses the possibility of polarizing immune responses to rationalize and individualize therapy with stem cell interventions, since generalized “one-size-fits-all” therapy is difficult to achieve in the face of the diverse complexities posed by stem cell biology. We also present the challenges to stem cell delivery in the context of the host related factors. Although we focus on the mesenchymal stem cells in this paper, the overarching rationale can be extrapolated to other types of stem cells as well. Hence, the broader purpose of this paper is to initiate a dialogue within the personalized medicine community by expanding the scope of inquiry in the field from pharmaceuticals to stem cells and related cell-based health interventions. PMID:20563265

  8. The stem cell secretome and its role in brain repair

    PubMed Central

    Drago, Denise; Cossetti, Chiara; Iraci, Nunzio; Gaude, Edoardo; Musco, Giovanna; Bachi, Angela; Pluchino, Stefano

    2014-01-01

    Compelling evidence exists that non-haematopoietic stem cells, including mesenchymal (MSCs) and neural/progenitor stem cells (NPCs), exert a substantial beneficial and therapeutic effect after transplantation in experimental central nervous system (CNS) disease models through the secretion of immune modulatory or neurotrophic paracrine factors. This paracrine hypothesis has inspired an alternative outlook on the use of stem cells in regenerative neurology. In this paradigm, significant repair of the injured brain may be achieved by injecting the biologics secreted by stem cells (secretome), rather than implanting stem cells themselves for direct cell replacement. The stem cell secretome (SCS) includes cytokines, chemokines and growth factors, and has gained increasing attention in recent years because of its multiple implications for the repair, restoration or regeneration of injured tissues. Thanks to recent improvements in SCS profiling and manipulation, investigators are now inspired to harness the SCS as a novel alternative therapeutic option that might ensure more efficient outcomes than current stem cell-based therapies for CNS repair. This review discusses the most recent identification of MSC- and NPC-secreted factors, including those that are trafficked within extracellular membrane vesicles (EVs), and reflects on their potential effects on brain repair. It also examines some of the most convincing advances in molecular profiling that have enabled mapping of the SCS. PMID:23827856

  9. A PITX3-EGFP Reporter Line Reveals Connectivity of Dopamine and Non-dopamine Neuronal Subtypes in Grafts Generated from Human Embryonic Stem Cells.

    PubMed

    Niclis, Jonathan C; Gantner, Carlos W; Hunt, Cameron P J; Kauhausen, Jessica A; Durnall, Jennifer C; Haynes, John M; Pouton, Colin W; Parish, Clare L; Thompson, Lachlan H

    2017-09-12

    Development of safe and effective stem cell-based therapies for brain repair requires an in-depth understanding of the in vivo properties of neural grafts generated from human stem cells. Replacing dopamine neurons in Parkinson's disease remains one of the most anticipated applications. Here, we have used a human PITX3-EGFP embryonic stem cell line to characterize the connectivity of stem cell-derived midbrain dopamine neurons in the dopamine-depleted host brain with an unprecedented level of specificity. The results show that the major A9 and A10 subclasses of implanted dopamine neurons innervate multiple, developmentally appropriate host targets but also that the majority of graft-derived connectivity is non-dopaminergic. These findings highlight the promise of stem cell-based procedures for anatomically correct reconstruction of specific neuronal pathways but also emphasize the scope for further refinement in order to limit the inclusion of uncharacterized and potentially unwanted cell types. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  10. Applications of human umbilical cord blood cells in central nervous system regeneration.

    PubMed

    Herranz, Antonio S; Gonzalo-Gobernado, Rafael; Reimers, Diana; Asensio, Maria J; Rodríguez-Serrano, Macarena; Bazán, Eulalia

    2010-03-01

    In recent decades, there has been considerable amount of information about embryonic stem cells (ES). The dilemma facing scientists interested in the development and use of human stem cells in replacement therapies is the source of these cells, i.e. the human embryo. There are many ethical and moral problems related to the use of these cells. Hematopoietic stem cells from umbilical cord blood have been proposed as an alternative source of embryonic stem cells. After exposure to different agents, these cells are able to express antigens of diverse cellular lineages, including the neural type. The In vitro manipulation of human umbilical cord blood (hUCB) cells has shown their stem capacity and plasticity. These cells are easily accessible, In vitro amplifiable, well tolerated by the host, and with more primitive molecular characteristics that give them great flexibility. Overall, these properties open a promising future for the use of hUCB in regenerative therapies for the Central Nervous System (CNS). This review will focus on the available literature concerning umbilical cord blood cells as a therapeutic tool for the treatment of neurodegenerative diseases.

  11. Scalable human ES culture for therapeutic use: propagation, differentiation, genetic modification and regulatory issues.

    PubMed

    Rao, M

    2008-01-01

    Embryonic stem cells unlike most adult stem cell populations can replicate indefinitely while preserving genetic, epigenetic, mitochondrial and functional profiles. ESCs are therefore an excellent candidate cell type for providing a bank of cells for allogenic therapy and for introducing targeted genetic modifications for therapeutic intervention. This ability of prolonged self-renewal of stem cells and the unique advantages that this offers for gene therapy, discovery efforts, cell replacement, personalized medicine and other more direct applications requires the resolution of several important manufacturing, gene targeting and regulatory issues. In this review, we assess some of the advance made in developing scalable culture systems, improvement in vector design and gene insertion technology and the changing regulatory landscape.

  12. Attenuation of teratoma formation by p27 overexpression in induced pluripotent stem cells.

    PubMed

    Matsu-ura, Toru; Sasaki, Hiroshi; Okada, Motoi; Mikoshiba, Katsuhiko; Ashraf, Muhammad

    2016-02-15

    Pluripotent stem cells, such as embryonic stem cells or induced pluripotent stem cells, have a great potential for regenerative medicine. Induced pluripotent stem cells, in particular, are suitable for replacement of tissue by autologous transplantation. However, tumorigenicity is a major risk in clinical application of both embryonic stem cells and induced pluripotent stem cells. This study explores the possibility of manipulating the cell cycle for inhibition of tumorigenicity. We genetically modified mouse induced pluripotent stem cells (miPSCs) to overexpress p27 tumor suppressor and examined their proliferation rate, gene expression, cardiac differentiation, tumorigenicity, and therapeutic potential in a mouse model of coronary artery ligation. Overexpression of p27 inhibited cell division of miPSCs, and that inhibition was dependent on the expression level of p27. p27 overexpressing miPSCs had pluripotency characteristics but lost stemness earlier than normal miPSCs during embryoid body and teratoma formation. These cellular characteristics led to none or smaller teratoma when the cells were injected into nude mice. Transplantation of both miPSCs and p27 overexpressing miPSCs into the infarcted mouse heart reduced the infarction size and improved left ventricular function. The overexpression of p27 attenuated tumorigenicity by reducing proliferation and earlier loss of stemness of miPSCs. The overexpression of p27 did not affect pluripotency and differentiation characteristics of miPSC. Therefore, regulation of the proliferation rate of miPSCs offers great therapeutic potential for repair of the injured myocardium.

  13. Concise review: reprogramming strategies for cardiovascular regenerative medicine: from induced pluripotent stem cells to direct reprogramming.

    PubMed

    Budniatzky, Inbar; Gepstein, Lior

    2014-04-01

    Myocardial cell-replacement therapies are emerging as novel therapeutic paradigms for myocardial repair but are hampered by the lack of sources of autologous human cardiomyocytes. The recent advances in stem cell biology and in transcription factor-based reprogramming strategies may provide exciting solutions to this problem. In the current review, we describe the different reprogramming strategies that can give rise to cardiomyocytes for regenerative medicine purposes. Initially, we describe induced pluripotent stem cell technology, a method by which adult somatic cells can be reprogrammed to yield pluripotent stem cells that could later be coaxed ex vivo to differentiate into cardiomyocytes. The generated induced pluripotent stem cell-derived cardiomyocytes could then be used for myocardial cell transplantation and tissue engineering strategies. We also describe the more recent direct reprogramming approaches that aim to directly convert the phenotype of one mature cell type (fibroblast) to another (cardiomyocyte) without going through a pluripotent intermediate cell type. The advantages and shortcomings of each strategy for cardiac regeneration are discussed, along with the hurdles that need to be overcome on the road to clinical translation.

  14. Stem Cell Therapy for the Central Nervous System in Lysosomal Storage Diseases.

    PubMed

    Siddiqi, Faez; Wolfe, John H

    2016-10-01

    Neurological diseases with genetic etiologies result in the loss or dysfunction of neural cells throughout the CNS. At present, few treatment options exist for the majority of neurogenetic diseases. Stem cell transplantation (SCT) into the CNS has the potential to be an effective treatment modality because progenitor cells may replace lost cells in the diseased brain, provide multiple trophic factors, or deliver missing proteins. This review focuses on the use of SCT in lysosomal storage diseases (LSDs), a large group of monogenic disorders with prominent CNS disease. In most patients the CNS disease results in intellectual disability that is refractory to current standard-of-care treatment. A large amount of preclinical work on brain-directed SCT has been performed in rodent LSD models. Cell types that have been used for direct delivery into the CNS include neural stem cells, embryonic and induced pluripotent stem cells, and mesenchymal stem cells. Hematopoietic stem cells have been an effective therapy for the CNS in a few LSDs and may be augmented by overexpression of the missing gene. Current barriers and potential strategies to improve SCT for translation into effective patient therapies are discussed.

  15. Harnessing the potential of lung stem cells for regenerative medicine.

    PubMed

    McQualter, Jonathan L; Anthony, Desiree; Bozinovski, Steven; Prêle, Cecilia M; Laurent, Geoffrey J

    2014-11-01

    In response to recurrent exposure to environmental insults such as allergens, pollution, irritants, smoke and viral/bacterial infection, the epithelium of the lung is continually damaged. Homeostasis of the lung requires a balance between immune regulation and promotion of tissue regeneration, which requires the co-ordinated proliferation and differentiation of stem and progenitor cells. In this review we reflect on the current understanding of lung epithelial stem and progenitor cells and advocate a model hierarchy in which self-renewing multipotent lung epithelial stem cells give rise to lineage restricted progenitor cells that repopulate airway and alveolar epithelial cell lineages during homeostasis and repair. We also discuss the role of mesenchymal progenitor cells in maintaining the structural integrity of the lung and propose a model in which mesenchymal cells act as the quintessential architects of lung regeneration by providing molecular signals, such as FGF-10, to regulate the fate and specificity of epithelial stem and progenitor cells. Moreover, we discuss the current status and future prospects for translating lung stem cell therapies to the clinic to replace, repair, or regenerate diseased lung tissue. This article is part of a directed issue entitled: Regenerative Medicine: the challenge of translation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Steady advance of stem cell therapies: report from the 2011 World Stem Cell Summit, Pasadena, California, October 3-5.

    PubMed

    Swan, Melanie

    2011-12-01

    Stem cell research and related therapies (including regenerative medicine and cellular therapies) could have a significant near-term impact on worldwide public health and aging. One reason is the industry's strong linkage between policy, science, industry, and patient advocacy, as was clear in the attendance and programming at the 7(th) annual World Stem Cell Summit held in Pasadena, California, October 3-5, 2011. A special conference session sponsored by the SENS Foundation discussed how stem cell therapies are being used to extend healthy life span. Stem cells are useful not only in cell-replacement therapies, but also in disease modeling, drug discovery, and drug toxicity screening. Stem cell therapies are currently being applied to over 50 diseases, including heart, lung, neurodegenerative, and eye disease, cancer, and human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). Dozens of companies are developing therapeutic solutions that are in different stages of clinical use and clinical trials. Some high-profile therapies include Dendreon's Provenge for prostate cancer, Geron's first-ever embryonic stem cell trials for spinal cord injury, Fibrocell's laViv cellular therapy for wrinkles, and well-established commercial skin substitutes (Organogenesis' Apligraf and Advanced BioHealing's Dermagraft). Stem cell policy issues under consideration include medical tourism, standards for large-scale stem cell manufacturing, and lingering ethical debates over the use of embryonic stem cells. Contemporary stem cell science advances include a focus on techniques for the direct reprogramming of cells from one lineage to another without returning to pluripotency as an intermediary step, improved means of generating and characterizing induced pluripotent cells, and progress in approaches to neurodegenerative disease.

  17. Proteomic Analysis of Mouse Oocytes Identifies PRMT7 as a Reprogramming Factor that Replaces SOX2 in the Induction of Pluripotent Stem Cells.

    PubMed

    Wang, Bingyuan; Pfeiffer, Martin J; Drexler, Hannes C A; Fuellen, Georg; Boiani, Michele

    2016-08-05

    The reprogramming process that leads to induced pluripotent stem cells (iPSCs) may benefit from adding oocyte factors to Yamanaka's reprogramming cocktail (OCT4, SOX2, KLF4, with or without MYC; OSK(M)). We previously searched for such facilitators of reprogramming (the reprogrammome) by applying label-free LC-MS/MS analysis to mouse oocytes, producing a catalog of 28 candidates that are (i) able to robustly access the cell nucleus and (ii) shared between mature mouse oocytes and pluripotent embryonic stem cells. In the present study, we hypothesized that our 28 reprogrammome candidates would also be (iii) abundant in mature oocytes, (iv) depleted after the oocyte-to-embryo transition, and (v) able to potentiate or replace the OSKM factors. Using LC-MS/MS and isotopic labeling methods, we found that the abundance profiles of the 28 proteins were below those of known oocyte-specific and housekeeping proteins. Of the 28 proteins, only arginine methyltransferase 7 (PRMT7) changed substantially during mouse embryogenesis and promoted the conversion of mouse fibroblasts into iPSCs. Specifically, PRMT7 replaced SOX2 in a factor-substitution assay, yielding iPSCs. These findings exemplify how proteomics can be used to prioritize the functional analysis of reprogrammome candidates. The LC-MS/MS data are available via ProteomeXchange with identifier PXD003093.

  18. Regeneration and replacement in the vertebrate inner ear.

    PubMed

    Matsui, Jonathan I; Parker, Mark A; Ryals, Brenda M; Cotanche, Douglas A

    2005-10-01

    Deafness affects more than 40 million people in the UK and the USA, and many more world-wide. The primary cause of hearing loss is damage to or death of the sensory receptor cells in the inner ear, the hair cells. Birds can readily regenerate their cochlear hair cells but the mammalian cochlea has shown no ability to regenerate after damage. Current research efforts are focusing on gene manipulation, gene therapy and stem cell transplantation for repairing or replacing damaged mammalian cochlear hair cells, which could lead to therapies for treating deafness in humans.

  19. Intervertebral disc-derived stem cells: implications for regenerative medicine and neural repair.

    PubMed

    Erwin, W Mark; Islam, Diana; Eftekarpour, Eftekhar; Inman, Robert D; Karim, Muhammad Zia; Fehlings, Michael G

    2013-02-01

    An in vitro and in vivo evaluation of intervertebral disc (IVD)-derived stem/progenitor cells. To determine the chondrogenic, adipogenic, osteogenic, and neurogenic differentiation capacity of disc-derived stem/progenitor cells in vitro and neurogenic differentiation in vivo. Tissue repair strategies require a source of appropriate cells that could be used to replace dead or damaged cells and tissues such as stem cells. Here we examined the potential use of IVD-derived stem cells in regenerative medicine approaches and neural repair. Nonchondrodystrophic canine IVD nucleus pulposus (NP) cells were used to generate stem/progenitor cells (NP progenitor cells [NPPCs]) and the NPPCs were differentiated in vitro into chondrogenic, adipogenic, and neurogenic lineages and in vivo into the neurogenic lineage. NPPCs were compared with bone marrow-derived mesenchymal (stromal) stem cells in terms of the expression of stemness genes. The expression of the neural crest marker protein 0 and the Brachyury gene were evaluated in NP cells and NPPCs. NPPCs contain stem/progenitor cells and express "stemness" genes such as Sox2, Oct3/4, Nanog, CD133, Nestin, and neural cell adhesion molecule but differ from mesenchymal (stromal) stem cells in the higher expression of the Nanog gene by NPPCs. NPPCs do not express protein 0 or the Brachyury gene both of which are expressed by the totality of IVD NP cells. The percentage of NPPCs within the IVD is 1% of the total as derived by colony-forming assay. NPPCs are capable of differentiating along chondrogenic, adipogenic, and neurogenic lineages in vitro and into oligodendrocyte, neuron, and astroglial specific precursor cells in vivo within the compact myelin-deficient shiverer mouse. We propose that the IVD NP represents a regenerative niche suggesting that the IVD could represent a readily accessible source of precursor cells for neural repair and regeneration.

  20. How Stem Cells Speak with Host Immune Cells in Inflammatory Brain Diseases

    PubMed Central

    Pluchino, Stefano; Cossetti, Chiara

    2014-01-01

    Advances in stem cell biology have raised great expectations that diseases and injuries of the central nervous system (CNS) may be ameliorated by the development of non-hematopoietic stem cell medicines. Yet, the application of adult stem cells as CNS therapeutics is challenging and the interpretation of some of the outcomes ambiguous. In fact, the initial idea that stem cell transplants work only via structural cell replacement has been challenged by the observation of consistent cellular signaling between the graft and the host. Cellular signaling is the foundation of coordinated actions and flexible responses, and arises via networks of exchanging and interacting molecules that transmit patterns of information between cells. Sustained stem cell graft-to-host communication leads to remarkable trophic effects on endogenous brain cells and beneficial modulatory actions on innate and adaptive immune responses in vivo, ultimately promoting the healing of the injured CNS. Among a number of adult stem cell types, mesenchymal stem cells (MSCs) and neural stem/precursor cells (NPCs) are being extensively investigated for their ability to signal to the immune system upon transplantation in experimental CNS diseases. Here, we focus on the main cellular signaling pathways that grafted MSCs and NPCs use to establish a therapeutically relevant cross talk with host immune cells, while examining the role of inflammation in regulating some of the bidirectionality of these communications. We propose that the identification of the players involved in stem cell signaling might contribute to the development of innovative, high clinical impact therapeutics for inflammatory CNS diseases. PMID:23633288

  1. Liver-Directed Human Amniotic Epithelial Cell Transplantation Improves Systemic Disease Phenotype in Hurler Syndrome Mouse Model.

    PubMed

    Rodriguez, Natalie S; Yanuaria, Lisa; Parducho, Kevin Murphy R; Garcia, Irving M; Varghese, Bino A; Grubbs, Brendan H; Miki, Toshio

    2017-07-01

    Mucopolysaccharidosis type 1 (MPS1) is an inherited lysosomal storage disorder caused by a deficiency in the glycosaminoglycan (GAG)-degrading enzyme α-l-iduronidase (IDUA). In affected patients, the systemic accumulation of GAGs results in skeletal dysplasia, neurological degeneration, multiple organ dysfunction, and early death. Current therapies, including enzyme replacement and bone marrow transplant, improve life expectancy but the benefits to skeletal and neurological phenotypes are limited. In this study, we tested the therapeutic efficacy of liver-directed transplantation of a placental stem cell, which possesses multilineage differentiation potential, low immunogenicity, and high lysosomal enzyme activity. Unfractionated human amniotic epithelial cells (hAECs) were transplanted directly into the liver of immunodeficient Idua knockout mouse neonates. The hAECs engraftment was immunohistochemically confirmed with anti-human mitochondria staining. Enzyme activity assays indicated that hAECs transplantation restored IDUA function in the liver and significantly decreased urinary GAG excretion. Histochemical and micro-computed tomography analyses revealed reduced GAG deposition in the phalanges joints and composition/morphology improvement of cranial and facial bones. Neurological assessment in the hAEC treated mice showed significant improvement of sensorimotor coordination in the hAEC treated mice compared to untreated mice. Results confirm that partial liver cell replacement with placental stem cells can provide long-term (>20 weeks) and systemic restoration of enzyme function, and lead to significant phenotypic improvement in the MPS1 mouse model. This preclinical data indicate that liver-directed placental stem cell transplantation may improve skeletal and neurological phenotypes of MPS1 patients. Stem Cells Translational Medicine 2017;6:1583-1594. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  2. Neural stem cell transplantation in central nervous system disorders: from cell replacement to neuroprotection.

    PubMed

    De Feo, Donatella; Merlini, Arianna; Laterza, Cecilia; Martino, Gianvito

    2012-06-01

    Transplantation of neural stem/precursor cells (NPCs) has been proposed as a promising therapeutic strategy in almost all neurological disorders characterized by the failure of central nervous system (CNS) endogenous repair mechanisms in restoring the tissue damage and rescuing the lost function. Nevertheless, recent evidence consistently challenges the limited view that transplantation of these cells is solely aimed at protecting the CNS from inflammatory and neurodegenerative damage through cell replacement. Recent preclinical data confirmed that transplanted NPCs may also exert a 'bystander' neuroprotective effect and identified a series of molecules - for example, immunomodulatory substances, neurotrophic growth factors, stem cell regulators as well as guidance molecules - whose in-situ secretion by NPCs is temporally and spatially orchestrated by environmental needs. A better understanding of the molecular and cellular mechanisms sustaining this 'therapeutic plasticity' is of pivotal importance for defining crucial aspects of the bench-to-beside translation of neural stem cell therapy, that is route and timing of administration as well as the best cellular source. Further insight into those latter issues is eagerly expected from the ongoing phase I/II clinical trials, while, on the other hand, new cellular sources are being developed, mainly by exploiting the new possibilities offered by cellular reprogramming. Nowadays, the research on NPC transplantation in neurological disorders is advancing on two different fronts: on one hand, recent preclinical data are uncovering the molecular basis of NPC therapeutic plasticity, offering a more solid rational framework for the design of clinical studies. On the other hand, pilot trials are highlighting the safety and feasibility issues of neural stem cell transplantation that need to be addressed before efficacy could be properly evaluated.

  3. The Application of Nanomaterials in Stem Cell Therapy for Some Neurological Diseases.

    PubMed

    Zhang, Guilong; Khan, Ahsan Ali; Wu, Hao; Chen, Lukui; Gu, Yuchun; Gu, Ning

    2018-02-08

    Stem cell therapy provides great promising therapeutic benefits for various neurological disorders. Cell transplantation has emerged as cell replacement application for nerve damage. Recently, nanomaterials obtain wide development in various industrial and medical fields, and nanoparticles have been applied in the neurological field for tracking and treating nervous system diseases. Combining stem cells with nanotechnology has raised more and more attentions; and it has demonstrated that the combination has huge effects on clinical diagnosis and therapeutics in multiple central nervous system diseases, meanwhile, improves prognosis. The aim of this review was to give a brief overview of the application of nanomaterials in stem cell therapy for neurological diseases. Nanoparticles not only promote stem cell proliferation and differentiation in vitro or in vivo, but also play dominant roles on stem cell imaging and tracking. Furthermore, via delivering genes or drugs, nanoparticles can participate in stem cell therapeutic applications for various neurological diseases, such as ischemic stroke, spinal cord injury (SCI), multiple sclerosis (MS), Parkinson's disease (PD), Alzheimer's disease (AD) and gliomas. However, nanoparticles have potential cytotoxic effects on nerve cells, which are related to their physicochemical properties. Nano-stem cell-based therapy as a promising strategy has the ability to affect neuronal repair and regeneration in the central nervous system. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  4. Stem cell signaling as a target for novel drug discovery: recent progress in the WNT and Hedgehog pathways.

    PubMed

    An, Songzhu Michael; Ding, Qiang Peter; Li, Ling-song

    2013-06-01

    One of the most exciting fields in biomedical research over the past few years is stem cell biology, and therapeutic application of stem cells to replace the diseased or damaged tissues is also an active area in development. Although stem cell therapy has a number of technical challenges and regulatory hurdles to overcome, the use of stem cells as tools in drug discovery supported by mature technologies and established regulatory paths is expected to generate more immediate returns. In particular, the targeting of stem cell signaling pathways is opening up a new avenue for drug discovery. Aberrations in these pathways result in various diseases, including cancer, fibrosis and degenerative diseases. A number of drug targets in stem cell signaling pathways have been identified. Among them, WNT and Hedgehog are two most important signaling pathways, which are the focus of this review. A hedgehog pathway inhibitor, vismodegib (Erivedge), has recently been approved by the US FDA for the treatment of skin cancer, while several drug candidates for the WNT pathway are entering clinical trials. We have discovered that the stem cell signaling pathways respond to traditional Chinese medicines. Substances isolated from herbal medicine may act specifically on components of stem cell signaling pathways with high affinities. As many of these events can be explained through molecular interactions, these phenomena suggest that discovery of stem cell-targeting drugs from natural products may prove to be highly successful.

  5. Isolation of sphere-forming stem cells from the mouse inner ear.

    PubMed

    Oshima, Kazuo; Senn, Pascal; Heller, Stefan

    2009-01-01

    The mammalian inner ear has very limited ability to regenerate lost sensory hair cells. This deficiency becomes apparent when hair cell loss leads to hearing loss as a result of either ototoxic insult or the aging process. Coincidently, with this inability to regenerate lost hair cells, the adult cochlea does not appear to harbor cells with a proliferative capacity that could serve as progenitor cells for lost cells. In contrast, adult mammalian vestibular sensory epithelia display a limited ability for hair cell regeneration, and sphere-forming cells with stem cell features can be isolated from the adult murine vestibular system. The neonatal inner ear, however, does harbor sphere-forming stem cells residing in cochlear and vestibular tissues. Here, we provide protocols to isolate sphere-forming stem cells from neonatal vestibular and cochlear sensory epithelia as well as from the spiral ganglion. We further describe procedures for sphere propagation, cell differentiation, and characterization of inner ear cell types derived from spheres. Sphere-forming stem cells from the mouse inner ear are an important tool for the development of cellular replacement strategies of damaged inner ears and are a bona fide progenitor cell source for transplantation studies.

  6. Mesenchymal stem cells and cardiac repair

    PubMed Central

    Nesselmann, Catharina; Ma, Nan; Bieback, Karen; Wagner, Wolfgang; Ho, Anthony; Konttinen, Yrjö T; Zhang, Hao; Hinescu, Mihail E; Steinhoff, Gustav

    2008-01-01

    Accumulating clinical and experimental evidence indicates that mesenchymal stem cells (MSCs) are promising cell types in the treatment of cardiac dysfunction. They may trigger production of reparative growth factors, replace damaged cells and create an environment that favours endogenous cardiac repair. However, identifying mechanisms which regulate the role of MSCs in cardiac repair is still at work. To achieve the maximal clinical benefits, ex vivo manipulation can further enhance MSC therapeutic potential. This review focuses on the mechanism of MSCs in cardiac repair, with emphasis on ex vivo manipulation. PMID:18684237

  7. Conditioned medium as a strategy for human stem cells chondrogenic differentiation.

    PubMed

    Alves da Silva, M L; Costa-Pinto, A R; Martins, A; Correlo, V M; Sol, P; Bhattacharya, M; Faria, S; Reis, R L; Neves, Nuno M

    2015-06-01

    Paracrine signalling from chondrocytes has been reported to increase the synthesis and expression of cartilage extracellular matrix (ECM) by stem cells. The use of conditioned medium obtained from chondrocytes for stimulating stem cells chondrogenic differentiation may be a very interesting alternative for moving into the clinical application of these cells, as chondrocytes could be partially replaced by stem cells for this type of application. In the present study we aimed to achieve chondrogenic differentiation of two different sources of stem cells using conditioned medium, without adding growth factors. We tested both human bone marrow-derived mesenchymal stem cells (hBSMCs) and human Wharton's jelly-derived stem cells (hWJSCs). Conditioned medium obtained from a culture of human articular chondrocytes was used to feed the cells during the experiment. Cultures were performed in previously produced three-dimensional (3D) scaffolds, composed of a blend of 50:50 chitosan:poly(butylene succinate). Both types of stem cells were able to undergo chondrogenic differentiation without the addition of growth factors. Cultures using hWJSCs showed significantly higher GAGs accumulation and expression of cartilage-related genes (aggrecan, Sox9 and collagen type II) when compared to hBMSCs cultures. Conditioned medium obtained from articular chondrocytes induced the chondrogenic differentiation of MSCs and ECM formation. Obtained results showed that this new strategy is very interesting and should be further explored for clinical applications. Copyright © 2013 John Wiley & Sons, Ltd.

  8. Bioengineered Lacrimal Gland Organ Regeneration in Vivo

    PubMed Central

    Hirayama, Masatoshi; Tsubota, Kazuo; Tsuji, Takashi

    2015-01-01

    The lacrimal gland plays an important role in maintaining a homeostatic environment for healthy ocular surfaces via tear secretion. Dry eye disease, which is caused by lacrimal gland dysfunction, is one of the most prevalent eye disorders and causes ocular discomfort, significant visual disturbances, and a reduced quality of life. Current therapies for dry eye disease, including artificial tear eye drops, are transient and palliative. The lacrimal gland, which consists of acini, ducts, and myoepithelial cells, develops from its organ germ via reciprocal epithelial-mesenchymal interactions during embryogenesis. Lacrimal tissue stem cells have been identified for use in regenerative therapeutic approaches aimed at restoring lacrimal gland functions. Fully functional organ replacement, such as for tooth and hair follicles, has also been developed via a novel three-dimensional stem cell manipulation, designated the Organ Germ Method, as a next-generation regenerative medicine. Recently, we successfully developed fully functional bioengineered lacrimal gland replacements after transplanting a bioengineered organ germ using this method. This study represented a significant advance in potential lacrimal gland organ replacement as a novel regenerative therapy for dry eye disease. In this review, we will summarize recent progress in lacrimal regeneration research and the development of bioengineered lacrimal gland organ replacement therapy. PMID:26264034

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

    PubMed

    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.

  10. Metastable Pluripotent States in NOD Mouse Derived ES Cells

    PubMed Central

    Hanna, Jacob; Markoulaki, Styliani; Mitalipova, Maisam; Cheng, Albert W.; Cassady, John P.; Staerk, Judith; Carey, Bryce W.; Lengner, Christopher J.; Foreman, Ruth; Love, Jennifer; Gao, Qing; Kim, Jongpil; Jaenisch, Rudolf

    2009-01-01

    Embryonic stem (ES) cells are isolated from the inner cell mass (ICM) of blastocysts, whereas epiblast stem cells (EpiSCs) are derived from the post-implantation epiblast and display a restricted developmental potential. Here we characterize pluripotent states in the non-obese diabetic (NOD) mouse strain, which prior to this study was considered “non-permissive” for ES cell derivation. We find that NOD stem cells can be stabilized by providing constitutive expression of Klf4 or c-Myc or small molecules that can replace these factors during in vitro reprogramming. The NOD ES and iPS cells appear “metastable”, as they acquire an alternative EpiSC-like identity after removal of the exogenous factors, while their reintroduction converts the cells back to ICM-like pluripotency. Our findings suggest that stem cells from different genetic backgrounds can assume distinct states of pluripotency in vitro, the stability of which is regulated by endogenous genetic determinants and can be modified by exogenous factors. PMID:19427283

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wagemaker, G.; Visser, T.P.; van Bekkum, D.W.

    alpha-Thalassemic heterozygous (Hbath/+) mice were used to investigate the possible selective advantage of transplanted normal (+/+) hemopoietic cells. Without conditioning by total-body irradiation (TBI), infusion of large numbers of normal bone marrow cells failed to correct the thalassemic peripheral blood phenotype. Since the recipients' stem cells are normal with respect to number and differentiation capacity, it was thought that the transplanted stem cells were not able to lodge, or that they were not stimulated to proliferate. Therefore, a nonlethal dose of TBI was given to temporarily reduce endogenous stem cell numbers and hemopoiesis. TBI doses of 2 or 3 Gymore » followed by infusion of normal bone marrow cells proved to be effective in replacing the thalassemic red cells by normal red cells, whereas a dose of 1 Gy was ineffective. It is concluded that cure of thalassemia by bone marrow transplantation does not necessarily require eradication of thalassemic stem cells. Consequently, the objectives of conditioning regimens for bone marrow transplantation of thalassemic patients (and possibly other nonmalignant hemopoietic disorders) should be reconsidered.« less

  12. Lung epithelial stem cells and their niches: Fgf10 takes center stage.

    PubMed

    Volckaert, Thomas; De Langhe, Stijn

    2014-01-01

    Throughout life adult animals crucially depend on stem cell populations to maintain and repair their tissues to ensure life-long organ function. Stem cells are characterized by their capacity to extensively self-renew and give rise to one or more differentiated cell types. These powerful stem cell properties are key to meet the changing demand for tissue replacement during normal lung homeostasis and regeneration after lung injury. Great strides have been made over the last few years to identify and characterize lung epithelial stem cells as well as their lineage relationships. Unfortunately, knowledge on what regulates the behavior and fate specification of lung epithelial stem cells is still limited, but involves communication with their microenvironment or niche, a local tissue environment that hosts and influences the behaviors or characteristics of stem cells and that comprises other cell types and extracellular matrix. As such, an intimate and dynamic epithelial-mesenchymal cross-talk, which is also essential during lung development, is required for normal homeostasis and to mount an appropriate regenerative response after lung injury. Fibroblast growth factor 10 (Fgf10) signaling in particular seems to be a well-conserved signaling pathway governing epithelial-mesenchymal interactions during lung development as well as between different adult lung epithelial stem cells and their niches. On the other hand, disruption of these reciprocal interactions leads to a dysfunctional epithelial stem cell-niche unit, which may culminate in chronic lung diseases such as chronic obstructive pulmonary disease (COPD), chronic asthma and idiopathic pulmonary fibrosis (IPF).

  13. Can stem cells really regenerate the human heart? Use your noggin, dickkopf! Lessons from developmental biology.

    PubMed

    Sommer, Paula

    2013-06-01

    The human heart is the first organ to develop and its development is fairly well characterised. In theory, the heart has the capacity to regenerate, as its cardiomyocytes may be capable of cell division and the adult heart contains a cardiac stem cell niche, presumably capable of differentiating into cardiomyocytes and other cardiac-associated cell types. However, as with most other organs, these mechanisms are not activated upon serious injury. Several experimental options to induce regeneration of the damaged heart tissue are available: activate the endogenous cardiomyocytes to divide, coax the endogenous population of stem cells to divide and differentiate, or add exogenous cell-based therapy to replace the lost cardiac tissue. This review is a summary of the recent research into all these avenues, discussing the reasons for the limited successes of clinical trials using stem cells after cardiac injury and explaining new advances in basic science. It concludes with a reiteration that chances of successful regeneration would be improved by understanding and implementing the basics of heart development and stem cell biology.

  14. Hepatocyte transplantation and advancements in alternative cell sources for liver-based regenerative medicine.

    PubMed

    Lee, Charlotte A; Sinha, Siddharth; Fitzpatrick, Emer; Dhawan, Anil

    2018-06-01

    Human hepatocyte transplantation has been actively perused as an alternative to liver replacement for acute liver failure and liver-based metabolic defects. Current challenges in this field include a limited cell source, reduced cell viability following cryopreservation and poor engraftment of cells into the recipient liver with consequent limited life span. As a result, alternative stem cell sources such as pluripotent stem cells, fibroblasts, hepatic progenitor cells, amniotic epithelial cells and mesenchymal stem/stromal cells (MSCs) can be used to generate induced hepatocyte like cells (HLC) with each technique exhibiting advantages and disadvantages. HLCs may have comparable function to primary human hepatocytes and could offer patient-specific treatment. However, long-term functionality of transplanted HLCs and the potential oncogenic risks of using stem cells have yet to be established. The immunomodulatory effects of MSCs are promising, and multiple clinical trials are investigating their effect in cirrhosis and acute liver failure. Here, we review the current status of hepatocyte transplantation, alternative cell sources to primary human hepatocytes and their potential in liver regeneration. We also describe recent clinical trials using hepatocytes derived from stem cells and their role in improving the phenotype of several liver diseases.

  15. Genetic Correction of Stem Cells in the Treatment of Inherited Diseases and Focus on Xeroderma Pigmentosum

    PubMed Central

    Rouanet, Sophie; Warrick, Emilie; Gache, Yannick; Scarzello, Sabine; Avril, Marie-Françoise; Bernerd, Françoise; Magnaldo, Thierry

    2013-01-01

    Somatic stem cells ensure tissue renewal along life and healing of injuries. Their safe isolation, genetic manipulation ex vivo and reinfusion in patients suffering from life threatening immune deficiencies (for example, severe combined immunodeficiency (SCID)) have demonstrated the efficacy of ex vivo gene therapy. Similarly, adult epidermal stem cells have the capacity to renew epidermis, the fully differentiated, protective envelope of our body. Stable skin replacement of severely burned patients have proven life saving. Xeroderma pigmentosum (XP) is a devastating disease due to severe defects in the repair of mutagenic DNA lesions introduced upon exposure to solar radiations. Most patients die from the consequences of budding hundreds of skin cancers in the absence of photoprotection. We have developed a safe procedure of genetic correction of epidermal stem cells isolated from XP patients. Preclinical and safety assessments indicate successful correction of XP epidermal stem cells in the long term and their capacity to regenerate a normal skin with full capacities of DNA repair. PMID:24113582

  16. Mechanical regulation of chondrogenesis

    PubMed Central

    2013-01-01

    Mechanical factors play a crucial role in the development of articular cartilage in vivo. In this regard, tissue engineers have sought to leverage native mechanotransduction pathways to enhance in vitro stem cell-based cartilage repair strategies. However, a thorough understanding of how individual mechanical factors influence stem cell fate is needed to predictably and effectively utilize this strategy of mechanically-induced chondrogenesis. This article summarizes some of the latest findings on mechanically stimulated chondrogenesis, highlighting several new areas of interest, such as the effects of mechanical stimulation on matrix maintenance and terminal differentiation, as well as the use of multifactorial bioreactors. Additionally, the roles of individual biophysical factors, such as hydrostatic or osmotic pressure, are examined in light of their potential to induce mesenchymal stem cell chondrogenesis. An improved understanding of biomechanically-driven tissue development and maturation of stem cell-based cartilage replacements will hopefully lead to the development of cell-based therapies for cartilage degeneration and disease. PMID:23809493

  17. CFHR1-Modified Neural Stem Cells Ameliorated Brain Injury in a Mouse Model of Neuromyelitis Optica Spectrum Disorders.

    PubMed

    Shi, Kaibin; Wang, Zhen; Liu, Yuanchu; Gong, Ye; Fu, Ying; Li, Shaowu; Wood, Kristofer; Hao, Junwei; Zhang, Guang-Xian; Shi, Fu-Dong; Yan, Yaping

    2016-11-01

    A major hurdle for effective stem cell therapy is ongoing inflammation in the target organ. Reconditioning the lesion microenvironment may be an effective way to promote stem cell therapy. In this study, we showed that engineered neural stem cells (NSCs) with complement factor H-related protein 1, a complement inhibitor protein, can attenuate inflammatory infiltration and immune-mediated damage of astrocytes, an important pathogenic progress in patients with neuromyelitis optica spectrum disorders. Furthermore, we demonstrated that transplantation of the complement factor H-related protein 1-modified NSCs effectively blocked the complement activation cascade and inhibited formation of the membrane attack complex, thus contributing to the protection of endogenous and transplanted NSC-differentiated astrocytes. Therefore, manipulation of the lesion microenvironment contributes to a more effective cell replacement therapeutic strategy for autoimmune diseases of the CNS. Copyright © 2016 by The American Association of Immunologists, Inc.

  18. The stem cell secretome and its role in brain repair.

    PubMed

    Drago, Denise; Cossetti, Chiara; Iraci, Nunzio; Gaude, Edoardo; Musco, Giovanna; Bachi, Angela; Pluchino, Stefano

    2013-12-01

    Compelling evidence exists that non-haematopoietic stem cells, including mesenchymal (MSCs) and neural/progenitor stem cells (NPCs), exert a substantial beneficial and therapeutic effect after transplantation in experimental central nervous system (CNS) disease models through the secretion of immune modulatory or neurotrophic paracrine factors. This paracrine hypothesis has inspired an alternative outlook on the use of stem cells in regenerative neurology. In this paradigm, significant repair of the injured brain may be achieved by injecting the biologics secreted by stem cells (secretome), rather than implanting stem cells themselves for direct cell replacement. The stem cell secretome (SCS) includes cytokines, chemokines and growth factors, and has gained increasing attention in recent years because of its multiple implications for the repair, restoration or regeneration of injured tissues. Thanks to recent improvements in SCS profiling and manipulation, investigators are now inspired to harness the SCS as a novel alternative therapeutic option that might ensure more efficient outcomes than current stem cell-based therapies for CNS repair. This review discusses the most recent identification of MSC- and NPC-secreted factors, including those that are trafficked within extracellular membrane vesicles (EVs), and reflects on their potential effects on brain repair. It also examines some of the most convincing advances in molecular profiling that have enabled mapping of the SCS. Copyright © 2013 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

  19. Geminin Participates in Differentiation Decisions of Adult Neural Stem Cells Transplanted in the Hemiparkinsonian Mouse Brain.

    PubMed

    Taouki, Ioanna; Tasiudi, Eve; Lalioti, Maria-Eleni; Kyrousi, Christina; Skavatsou, Eleni; Kaplani, Konstantina; Lygerou, Zoi; Kouvelas, Elias D; Mitsacos, Adamantia; Giompres, Panagiotis; Taraviras, Stavros

    2017-08-15

    Neural stem cells have been considered as a source of stem cells that can be used for cell replacement therapies in neurodegenerative diseases, as they can be isolated and expanded in vitro and can be used for autologous grafting. However, due to low percentages of survival and varying patterns of differentiation, strategies that will enhance the efficacy of transplantation are under scrutiny. In this article, we have examined whether alterations in Geminin's expression, a protein that coordinates the balance between self-renewal and differentiation, can improve the properties of stem cells transplanted in 6-OHDA hemiparkinsonian mouse model. Our results indicate that, in the absence of Geminin, grafted cells differentiating into dopaminergic neurons were decreased, while an increased number of oligodendrocytes were detected. The number of proliferating multipotent cells was not modified by the absence of Geminin. These findings encourage research related to the impact of Geminin on transplantations for neurodegenerative disorders, as an important molecule in influencing differentiation decisions of the cells composing the graft.

  20. Embryonic stem cells and prospects for their use in regenerative medicine approaches to motor neurone disease.

    PubMed

    Christou, Y A; Moore, H D; Shaw, P J; Monk, P N

    2007-10-01

    Human embryonic stem cells are pluripotent cells with the potential to differentiate into any cell type in the presence of appropriate stimulatory factors and environmental cues. Their broad developmental potential has led to valuable insights into the principles of developmental and cell biology and to the proposed use of human embryonic stem cells or their differentiated progeny in regenerative medicine. This review focuses on the prospects for the use of embryonic stem cells in cell-based therapy for motor neurone disease or amyotrophic lateral sclerosis, a progressive neurodegenerative disease that specifically affects upper and lower motor neurones and leads ultimately to death from respiratory failure. Stem cell-derived motor neurones could conceivably be used to replace the degenerated cells, to provide authentic substrates for drug development and screening and for furthering our understanding of disease mechanisms. However, to reliably and accurately culture motor neurones, the complex pathways by which differentiation occurs in vivo must be understood and reiterated in vitro by embryonic stem cells. Here we discuss the need for new therapeutic strategies in the treatment of motor neurone disease, the developmental processes that result in motor neurone formation in vivo, a number of experimental approaches to motor neurone production in vitro and recent progress in the application of stem cells to the treatment and understanding of motor neurone disease.

  1. The neurotrophic effects of different human dental mesenchymal stem cells.

    PubMed

    Kolar, Mallappa K; Itte, Vinay N; Kingham, Paul J; Novikov, Lev N; Wiberg, Mikael; Kelk, Peyman

    2017-10-03

    The current gold standard treatment for peripheral nerve injury is nerve grafting but this has disadvantages such as donor site morbidity. New techniques focus on replacing these grafts with nerve conduits enhanced with growth factors and/or various cell types such as mesenchymal stem cells (MSCs). Dental-MSCs (D-MSCs) including stem cells obtained from apical papilla (SCAP), dental pulp stem cells (DPSC), and periodontal ligament stem cells (PDLSC) are potential sources of MSCs for nerve repair. Here we present the characterization of various D-MSCs from the same human donors for peripheral nerve regeneration. SCAP, DPSC and PDLSC expressed BDNF, GDNF, NGF, NTF3, ANGPT1 and VEGFA growth factor transcripts. Conditioned media from D-MSCs enhanced neurite outgrowth in an in vitro assay. Application of neutralizing antibodies showed that brain derived neurotrophic factor plays an important mechanistic role by which the D-MSCs stimulate neurite outgrowth. SCAP, DPSC and PDLSC were used to treat a 10 mm nerve gap defect in a rat sciatic nerve injury model. All the stem cell types significantly enhanced axon regeneration after two weeks and showed neuroprotective effects on the dorsal root ganglia neurons. Overall the results suggested SCAP to be the optimal dental stem cell type for peripheral nerve repair.

  2. Pharmacological mimicking of caloric restriction elicits epigenetic reprogramming of differentiated cells to stem-like self-renewal states.

    PubMed

    Oliveras-Ferraros, Cristina; Vazquez-Martin, Alejandro; Menendez, Javier A

    2010-10-01

    Networks of oncogenes and tumor suppressor genes that control cancer cell proliferation also regulate stem cell renewal and possibly stem cell aging. Because (de)differentiation processes might dictate tumor cells to retrogress to a more stem-like state in response to aging-relevant epigenetic and/or environmental players, we recently envisioned that cultured human cancer cells might be used as reliable models to test the ability of antiaging interventions for promoting the initiation and maintenance of self-renewing divisions. Cancer cell lines naturally bearing undetectable amounts of stem/progenitor-like cell populations were continuously cultured in the presence of the caloric restriction mimetic metformin for several months. Microarray technology was employed to profile expression of genes related to the identification, growth, and differentiation of stem cells. Detection of functionally related gene groups using a pathway analysis package provided annotated genetic signatures over- and underexpressed in response to pharmacological mimicking of caloric restriction. By following this methodological approach, we recently obtained data fitting a model in which, in response to chronic impairment of cellular bioenergetics imposed by metformin-induced mitochondrial uncoupling as assessed by the phosphorylation state of cAMP-response element binding protein (CREB), tumor cells can retrogress from a differentiated state to a more CD44(+) stem-like primitive state epigenetically governed by the Polycomb-group suppressor BMI1-a crucial "stemness" gene involved in the epigenetic maintenance of adult stem cells. These findings might provide a novel molecular avenue to investigate if antiaging benefits from caloric restriction mimetics might relate to their ability to epigenetically reprogram stemness while prolonging the capacity of stem-like cell states to proliferate, differentiate, and replace mature cells in adult aging tissues.

  3. Retinal pigment epithelium culture;a potential source of retinal stem cells.

    PubMed

    Akrami, Hassan; Soheili, Zahra-Soheila; Khalooghi, Keynoush; Ahmadieh, Hamid; Rezaie-Kanavi, Mojgan; Samiei, Shahram; Davari, Malihe; Ghaderi, Shima; Sanie-Jahromi, Fatemeh

    2009-07-01

    To establish human retinal pigment epithelial (RPE) cell culture as a source for cell replacement therapy in ocular diseases. Human cadaver globes were used to isolate RPE cells. Each globe was cut into several pieces of a few millimeters in size. After removing the sclera and choroid, remaining tissues were washed in phosphate buffer saline and RPE cells were isolated using dispase enzyme solution and cultured in Dulbecco's Modified Eagle's Medium: Nutrient Mixture F-12 supplemented with 10% fetal calf serum. Primary cultures of RPE cells were established and spheroid colonies related to progenitor/stem cells developed in a number of cultures. The colonies included purely pigmented or mixed pigmented and non-pigmented cells. After multiple cellular passages, several types of photoreceptors and neural-like cells were detected morphologically. Cellular plasticity in RPE cell cultures revealed promising results in terms of generation of stem/progenitor cells from human RPE cells. Whether the spheroids and neural-like retinal cells were directly derived from retinal stem cells or offspring of trans-differentiating or de-differentiating RPE cells remains to be answered.

  4. Retinal Pigment Epithelium Culture;a Potential Source of Retinal Stem Cells

    PubMed Central

    Akrami, Hassan; Soheili, Zahra-Soheila; Khalooghi, Keynoush; Ahmadieh, Hamid; Rezaie-Kanavi, Mojgan; Samiei, Shahram; Davari, Malihe; Ghaderi, Shima; Sanie-Jahromi, Fatemeh

    2009-01-01

    Purpose To establish human retinal pigment epithelial (RPE) cell culture as a source for cell replacement therapy in ocular diseases. Methods Human cadaver globes were used to isolate RPE cells. Each globe was cut into several pieces of a few millimeters in size. After removing the sclera and choroid, remaining tissues were washed in phosphate buffer saline and RPE cells were isolated using dispase enzyme solution and cultured in Dulbecco’s Modified Eagle’s Medium: Nutrient Mixture F-12 supplemented with 10% fetal calf serum. Results Primary cultures of RPE cells were established and spheroid colonies related to progenitor/stem cells developed in a number of cultures. The colonies included purely pigmented or mixed pigmented and non-pigmented cells. After multiple cellular passages, several types of photoreceptors and neural-like cells were detected morphologically. Conclusion Cellular plasticity in RPE cell cultures revealed promising results in terms of generation of stem/progenitor cells from human RPE cells. Whether the spheroids and neural-like retinal cells were directly derived from retinal stem cells or offspring of trans-differentiating or de-differentiating RPE cells remains to be answered. PMID:23198062

  5. Bone Marrow Transplantation

    MedlinePlus

    Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains immature cells, called stem cells. The ... platelets, which help the blood to clot. A bone marrow transplant is a procedure that replaces a ...

  6. Letermovir

    MedlinePlus

    Letermovir is used to help prevent cytomegalovirus (CMV) infection and disease in certain people who have received a hematopoietic stem-cell transplant (HSCT; a procedure that replaces diseased bone marrow with ...

  7. Therapeutic modulation of growth factors and cytokines in regenerative medicine.

    PubMed

    Ioannidou, Effie

    2006-01-01

    Regeneration that takes place in the human body is limited throughout life. Therefore, when organs are irreparably damaged, they are usually replaced with an artificial device or donor organ. The term "regenerative medicine" covers the restoration or replacement of cells, tissues, and organs. Stem cells play a major role in regenerative medicine by providing the way to repopulate organs damaged by disease. Stem cells have the ability to self renew and to regenerate cells of diverse lineages within the tissue in which they reside. Stem cells could originate from embryos or adult tissues. Growth factors are proteins that may act locally or systemically to affect the growth of cells in several ways. Various cell activities, including division, are influenced by growth factors. Cytokines are a family of low-molecular-weight proteins that are produced by numerous cell types and are responsible for regulating the immune response, inflammation, tissue remodeling and cellular differentiation. Target cells of growth factors and cytokines are mesenchymal, epithelial and endothelial cells. These molecules frequently have overlapping activities and can act in an autocrine or paracrine fashion. A complex network of growth factors and cytokines guides cellular differentiation and regeneration in all organs and tissues. The aim of this paper is to review the role of growth factors and cytokines in different organs or systems and explore their therapeutic application in regenerative medicine. The role of stem cells combined with growth factors and cytokines in the regeneration of vascular and hematopoietic, neural, skeletal, pancreatic, periodontal, and mucosal tissue is reviewed. There is evidence that supports the use of growth factors and cytokines in the treatment of neurological diseases, diabetes, cardiovascular disease, periodontal disease, cancer and its complication, oral mucositis. After solving the ethical issues and establishing clear and reasonable regulations, regenerative medicine through stem cell application combined with specific growth factors and cytokines will have great potential in curing a variety of human diseases.

  8. The control of epidermal stem cells (holoclones) in the treatment of massive full-thickness burns with autologous keratinocytes cultured on fibrin.

    PubMed

    Pellegrini, G; Ranno, R; Stracuzzi, G; Bondanza, S; Guerra, L; Zambruno, G; Micali, G; De Luca, M

    1999-09-27

    Cell therapy is an emerging therapeutic strategy aimed at replacing or repairing severely damaged tissues with cultured cells. Epidermal regeneration obtained with autologous cultured keratinocytes (cultured autografts) can be life-saving for patients suffering from massive full-thickness burns. However, the widespread use of cultured autografts has been hampered by poor clinical results that have been consistently reported by different burn units, even when cells were applied on properly prepared wound beds. This might arise from the depletion of epidermal stem cells (holoclones) in culture. Depletion of holoclones can occur because of (i) incorrect culture conditions, (ii) environmental damage of the exposed basal layer of cultured grafts, or (iii) use of new substrates or culture technologies not pretested for holoclone preservation. The aim of this study was to show that, if new keratinocyte culture technologies and/or "delivery systems" are proposed, a careful evaluation of epidermal stem cell preservation is essential for the clinical performance of this life-saving technology. Fibrin was chosen as a potential substrate for keratinocyte cultivation. Stem cells were monitored by clonal analysis using the culture system originally described by Rheinwald and Green as a reference. Massive full-thickness burns were treated with the composite allodermis/cultured autograft technique. We show that: (i) the relative percentage of holoclones, meroclones, and paraclones is maintained when keratinocytes are cultivated on fibrin, proving that fibrin does not induce clonal conversion and consequent loss of epidermal stem cells; (ii) the clonogenic ability, growth rate, and long-term proliferative potential are not affected by the new culture system; (iii) when fibrin-cultured autografts bearing stem cells are applied on massive full-thickness burns, the "take" of keratinocytes is high, reproducible, and permanent; and (iv) fibrin allows a significant reduction of the cost of cultured autografts and eliminates problems related to their handling and transportation. Our data demonstrate that: (i) cultured autografts bearing stem cells can indeed rapidly and permanently cover a large body surface; and (ii) fibrin is a suitable substrate for keratinocyte cultivation and transplantation. These data lend strength to the concept that the success of cell therapy at a clinical level requires cultivation and transplantation of stem cells. We therefore suggest that the proposal of a culture system aimed at the replacement of any severely damaged self-renewing tissue should be preceded by a careful evaluation of its stem cell population.

  9. Development of decellularized scaffolds for stem cell-driven tissue engineering.

    PubMed

    Rana, Deepti; Zreiqat, Hala; Benkirane-Jessel, Nadia; Ramakrishna, Seeram; Ramalingam, Murugan

    2017-04-01

    Organ transplantation is an effective treatment for chronic organ dysfunctioning conditions. However, a dearth of available donor organs for transplantation leads to the death of numerous patients waiting for a suitable organ donor. The potential of decellularized scaffolds, derived from native tissues or organs in the form of scaffolds has been evolved as a promising approach in tissue-regenerative medicine for translating functional organ replacements. In recent years, donor organs, such as heart, liver, lung and kidneys, have been reported to provide acellular extracellular matrix (ECM)-based scaffolds through the process called 'decellularization' and proved to show the potential of recellularization with selected cell populations, particularly with stem cells. In fact, decellularized stem cell matrix (DSCM) has also emerged as a potent biological scaffold for controlling stem cell fate and function during tissue organization. Despite the proven potential of decellularized scaffolds in tissue engineering, the molecular mechanism responsible for stem cell interactions with decellularized scaffolds is still unclear. Stem cells interact with, and respond to, various signals/cues emanating from their ECM. The ability to harness the regenerative potential of stem cells via decellularized ECM-based scaffolds has promising implications for tissue-regenerative medicine. Keeping these points in view, this article reviews the current status of decellularized scaffolds for stem cells, with particular focus on: (a) concept and various methods of decellularization; (b) interaction of stem cells with decellularized scaffolds; (c) current recellularization strategies, with associated challenges; and (iv) applications of the decellularized scaffolds in stem cell-driven tissue engineering and regenerative medicine. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  10. A review of gene delivery and stem cell based therapies for regenerating inner ear hair cells.

    PubMed

    Devarajan, Keerthana; Staecker, Hinrich; Detamore, Michael S

    2011-09-13

    Sensory neural hearing loss and vestibular dysfunction have become the most common forms of sensory defects, affecting millions of people worldwide. Developing effective therapies to restore hearing loss is challenging, owing to the limited regenerative capacity of the inner ear hair cells. With recent advances in understanding the developmental biology of mammalian and non-mammalian hair cells a variety of strategies have emerged to restore lost hair cells are being developed. Two predominant strategies have developed to restore hair cells: transfer of genes responsible for hair cell genesis and replacement of missing cells via transfer of stem cells. In this review article, we evaluate the use of several genes involved in hair cell regeneration, the advantages and disadvantages of the different viral vectors employed in inner ear gene delivery and the insights gained from the use of embryonic, adult and induced pluripotent stem cells in generating inner ear hair cells. Understanding the role of genes, vectors and stem cells in therapeutic strategies led us to explore potential solutions to overcome the limitations associated with their use in hair cell regeneration.

  11. Recent progress on normal and malignant pancreatic stem/progenitor cell research: therapeutic implications for the treatment of type 1 or 2 diabetes mellitus and aggressive pancreatic cancer

    PubMed Central

    Mimeault, M; Batra, S K

    2010-01-01

    Recent progress on pancreatic stem/progenitor cell research has revealed that the putative multipotent pancreatic stem/progenitor cells and/or more committed beta cell precursors may persist in the pancreatic gland in adult life. The presence of immature pancreatic cells with stem cell-like properties offers the possibility of stimulating their in vivo expansion and differentiation or to use their ex vivo expanded progenies for beta cell replacement-based therapies for type 1 or 2 diabetes mellitus in humans. In addition, the transplantation of either insulin-producing beta cells derived from embryonic, fetal and other tissue-resident adult stem/progenitor cells or genetically modified adult stem/progenitor cells may also constitute alternative promising therapies for treating diabetic patients. The genetic and/or epigenetic alterations in putative pancreatic adult stem/progenitor cells and/or their early progenies may, however, contribute to their acquisition of a dysfunctional behaviour as well as their malignant transformation into pancreatic cancer stem/progenitor cells. More particularly, the activation of distinct tumorigenic signalling cascades, including the hedgehog, epidermal growth factor–epidermal growth factor receptor (EGF–EGFR) system, wingless ligand (Wnt)/β-catenin and/or stromal cell-derived factor-1 (SDF-1)–CXC chemokine receptor 4 (CXCR4) pathways may play a major role in the sustained growth, survival, metastasis and/or drug resistance of pancreatic cancer stem/progenitor cells and their further differentiated progenies. The combination of drugs that target the oncogenic elements in pancreatic cancer stem/progenitor cells and their microenvironment, with the conventional chemotherapeutic regimens, could represent promising therapeutic strategies. These novel targeted therapies should lead to the development of more effective treatments of locally advanced and metastatic pancreatic cancers, which remain incurable with current therapies. PMID:18791122

  12. Potential for a pluripotent adult stem cell treatment for acute radiation sickness

    PubMed Central

    Rodgerson, Denis O; Reidenberg, Bruce E; Harris, Alan G; Pecora, Andrew L

    2012-01-01

    Accidental radiation exposure and the threat of deliberate radiation exposure have been in the news and are a public health concern. Experience with acute radiation sickness has been gathered from atomic blast survivors of Hiroshima and Nagasaki and from civilian nuclear accidents as well as experience gained during the development of radiation therapy for cancer. This paper reviews the medical treatment reports relevant to acute radiation sickness among the survivors of atomic weapons at Hiroshima and Nagasaki, among the victims of Chernobyl, and the two cases described so far from the Fukushima Dai-Ichi disaster. The data supporting the use of hematopoietic stem cell transplantation and the new efforts to expand stem cell populations ex vivo for infusion to treat bone marrow failure are reviewed. Hematopoietic stem cells derived from bone marrow or blood have a broad ability to repair and replace radiation induced damaged blood and immune cell production and may promote blood vessel formation and tissue repair. Additionally, a constituent of bone marrow-derived, adult pluripotent stem cells, very small embryonic like stem cells, are highly resistant to ionizing radiation and appear capable of regenerating radiation damaged tissue including skin, gut and lung. PMID:24520532

  13. Epithelial Label-Retaining Cells Are Absent during Tooth Cycling in Salmo salar and Polypterus senegalus.

    PubMed

    Vandenplas, Sam; Willems, Maxime; Witten, P Eckhard; Hansen, Tom; Fjelldal, Per Gunnar; Huysseune, Ann

    2016-01-01

    The Atlantic salmon (Salmo salar) and African bichir (Polypterus senegalus) are both actinopterygian fish species that continuously replace their teeth without the involvement of a successional dental lamina. Instead, they share the presence of a middle dental epithelium: an epithelial tier enclosed by inner and outer dental epithelium. It has been hypothesized that this tier could functionally substitute for a successional dental lamina and might be a potential niche to house epithelial stem cells involved in tooth cycling. Therefore, in this study we performed a BrdU pulse chase experiment on both species to (1) determine the localization and extent of proliferating cells in the dental epithelial layers, (2) describe cell dynamics and (3) investigate if label-retaining cells are present, suggestive for the putative presence of stem cells. Cells proliferate in the middle dental epithelium, outer dental epithelium and cervical loop at the lingual side of the dental organ to form a new tooth germ. Using long chase times, both in S. salar (eight weeks) and P. senegalus (eight weeks and twelve weeks), we could not reveal the presence of label-retaining cells in the dental organ. Immunostaining of P. senegalus dental organs for the transcription factor Sox2, often used as a stem cell marker, labelled cells in the zone of outer dental epithelium which grades into the oral epithelium (ODE transition zone) and the inner dental epithelium of a successor only. The location of Sox2 distribution does not provide evidence for epithelial stem cells in the dental organ and, more specifically, in the middle dental epithelium. Comparison of S. salar and P. senegalus reveals shared traits in tooth cycling and thus advances our understanding of the developmental mechanism that ensures lifelong replacement.

  14. Epithelial Label-Retaining Cells Are Absent during Tooth Cycling in Salmo salar and Polypterus senegalus

    PubMed Central

    Vandenplas, Sam; Willems, Maxime; Witten, P. Eckhard; Hansen, Tom; Fjelldal, Per Gunnar; Huysseune, Ann

    2016-01-01

    The Atlantic salmon (Salmo salar) and African bichir (Polypterus senegalus) are both actinopterygian fish species that continuously replace their teeth without the involvement of a successional dental lamina. Instead, they share the presence of a middle dental epithelium: an epithelial tier enclosed by inner and outer dental epithelium. It has been hypothesized that this tier could functionally substitute for a successional dental lamina and might be a potential niche to house epithelial stem cells involved in tooth cycling. Therefore, in this study we performed a BrdU pulse chase experiment on both species to (1) determine the localization and extent of proliferating cells in the dental epithelial layers, (2) describe cell dynamics and (3) investigate if label-retaining cells are present, suggestive for the putative presence of stem cells. Cells proliferate in the middle dental epithelium, outer dental epithelium and cervical loop at the lingual side of the dental organ to form a new tooth germ. Using long chase times, both in S. salar (eight weeks) and P. senegalus (eight weeks and twelve weeks), we could not reveal the presence of label-retaining cells in the dental organ. Immunostaining of P. senegalus dental organs for the transcription factor Sox2, often used as a stem cell marker, labelled cells in the zone of outer dental epithelium which grades into the oral epithelium (ODE transition zone) and the inner dental epithelium of a successor only. The location of Sox2 distribution does not provide evidence for epithelial stem cells in the dental organ and, more specifically, in the middle dental epithelium. Comparison of S. salar and P. senegalus reveals shared traits in tooth cycling and thus advances our understanding of the developmental mechanism that ensures lifelong replacement. PMID:27049953

  15. Regenerative medicine for Parkinson's disease using differentiated nerve cells derived from human buccal fat pad stem cells.

    PubMed

    Takahashi, Haruka; Ishikawa, Hiroshi; Tanaka, Akira

    2017-04-01

    The purpose of this study was to evaluate the utility of human adipose stem cells derived from the buccal fat pad (hBFP-ASCs) for nerve regeneration. Parkinson's disease (PD) is a neurodegenerative disorder characterized by progressive death of dopaminergic neurons. PD is a candidate disease for cell replacement therapy because it has no fundamental therapeutic methods. We examined the properties of neural-related cells induced from hBFP-ASCs as a cell source for PD treatment. hBFP-ASCs were cultured in neurogenic differentiation medium for about 2 weeks. After the morphology of hBFP-ASCs changed to neural-like cells, the medium was replaced with neural maintenance medium. Cells differentiated from hBFP-ASCs showed neuron-like structures and expressed neuron markers (β3-tubulin, neurofilament 200, and microtubule-associated protein 2), an astrocyte marker (glial fibrillary acidic protein), or dopaminergic neuron-related marker (tyrosine hydroxylase). Induced neural cells were transplanted into a 6-hydroxydopamine (6-OHDA)-lesioned rat hemi-parkinsonian model. At 4 weeks after transplantation, 6-OHDA-lesioned rats were subjected to apomorphine-induced rotation analysis. The transplanted cells survived in the brain of rats as dopaminergic neural cells. No tumor formation was found after cell transplantation. We demonstrated differentiation of hBFP-ASCs into neural cells, and that transplantation of these neural cells improved the symptoms of model rats. Our results suggest that neurons differentiated from hBFP-ASCs would be applicable to cell replacement therapy of PD.

  16. Gelatin-based microcarriers as embryonic stem cell delivery system in bone tissue engineering: an in-vitro study.

    PubMed

    Tielens, S; Declercq, H; Gorski, T; Lippens, E; Schacht, E; Cornelissen, M

    2007-03-01

    Mouse embryonic stem cells were cultured on commercially available biodegradable macroporous microcarriers. A culture period of 1-2 weeks was needed to colonize the microcarriers. Embryonic stem cells retained their pluripotency for up to 14 days when cultured in medium supplemented with leukemia inhibitory factor. Replacing this medium by differentiation medium for 2 weeks initiated osteogenic differentiation. Encapsulation of the cell-loaded microcarriers in photopolymerizable polymers (methacrylate-endcapped poly-D,L-lactide-co-caprolactone), triacetin/hydroxyethylmethacrylate (HEMA) as solvent and with/without gelatin as porogen, resulted in a homogeneous distribution of the microcarriers in the polymer. As observed by transmission electron microscopy, viability of the cells was optimal when gelatin was omitted and when using triacetin instead of HEMA.

  17. Organ engineering--combining stem cells, biomaterials, and bioreactors to produce bioengineered organs for transplantation.

    PubMed

    Murphy, Sean Vincent; Atala, Anthony

    2013-03-01

    Often the only treatment available for patients suffering from diseased and injured organs is whole organ transplant. However, there is a severe shortage of donor organs for transplantation. The goal of organ engineering is to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Recent progress in stem cell biology, biomaterials, and processes such as organ decellularization and electrospinning has resulted in the generation of bioengineered blood vessels, heart valves, livers, kidneys, bladders, and airways. Future advances that may have a significant impact for the field include safe methods to reprogram a patient's own cells to directly differentiate into functional replacement cell types. The subsequent combination of these cells with natural, synthetic and/or decellularized organ materials to generate functional tissue substitutes is a real possibility. This essay reviews the current progress, developments, and challenges facing researchers in their goal to create replacement tissues and organs for patients. Copyright © 2013 WILEY Periodicals, Inc.

  18. Engineered cartilaginous tubes for tracheal tissue replacement via self-assembly and fusion of human mesenchymal stem cell constructs.

    PubMed

    Dikina, Anna D; Strobel, Hannah A; Lai, Bradley P; Rolle, Marsha W; Alsberg, Eben

    2015-06-01

    There is a critical need to engineer a neotrachea because currently there are no long-term treatments for tracheal stenoses affecting large portions of the airway. In this work, a modular tracheal tissue replacement strategy was developed. High-cell density, scaffold-free human mesenchymal stem cell-derived cartilaginous rings and tubes were successfully generated through employment of custom designed culture wells and a ring-to-tube assembly system. Furthermore, incorporation of transforming growth factor-β1-delivering gelatin microspheres into the engineered tissues enhanced chondrogenesis with regard to tissue size and matrix production and distribution in the ring- and tube-shaped constructs, as well as luminal rigidity of the tubes. Importantly, all engineered tissues had similar or improved biomechanical properties compared to rat tracheas, which suggests they could be transplanted into a small animal model for airway defects. The modular, bottom up approach used to grow stem cell-based cartilaginous tubes in this report is a promising platform to engineer complex organs (e.g., trachea), with control over tissue size and geometry, and has the potential to be used to generate autologous tissue implants for human clinical applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Differentiation of human-induced pluripotent stem cells into insulin-producing clusters.

    PubMed

    Shaer, Anahita; Azarpira, Negar; Vahdati, Akbar; Karimi, Mohammad Hosein; Shariati, Mehrdad

    2015-02-01

    In diabetes mellitus type 1, beta cells are mostly destroyed; while in diabetes mellitus type 2, beta cells are reduced by 40% to 60%. We hope that soon, stem cells can be used in diabetes therapy via pancreatic beta cell replacement. Induced pluripotent stem cells are a kind of stem cell taken from an adult somatic cell by "stimulating" certain genes. These induced pluripotent stem cells may be a promising source of cell therapy. This study sought to produce isletlike clusters of insulin-producing cells taken from induced pluripotent stem cells. A human-induced pluripotent stem cell line was induced into isletlike clusters via a 4-step protocol, by adding insulin, transferrin, and selenium (ITS), N2, B27, fibroblast growth factor, and nicotinamide. During differentiation, expression of pancreatic β-cell genes was evaluated by reverse transcriptase-polymerase chain reaction; the morphologic changes of induced pluripotent stem cells toward isletlike clusters were observed by a light microscope. Dithizone staining was used to stain these isletlike clusters. Insulin produced by these clusters was evaluated by radio immunosorbent assay, and the secretion capacity was analyzed with a glucose challenge test. Differentiation was evaluated by analyzing the morphology, dithizone staining, real-time quantitative polymerase chain reaction, and immunocytochemistry. Gene expression of insulin, glucagon, PDX1, NGN3, PAX4, PAX6, NKX6.1, KIR6.2, and GLUT2 were documented by analyzing real-time quantitative polymerase chain reaction. Dithizone-stained cellular clusters were observed after 23 days. The isletlike clusters significantly produced insulin. The isletlike clusters could increase insulin secretion after a glucose challenge test. This work provides a model for studying the differentiation of human-induced pluripotent stem cells to insulin-producing cells.

  20. TORC1 is required to balance cell proliferation and cell death in planarians

    PubMed Central

    Tu, Kimberly C.; Pearson, Bret J.; Alvarado, Alejandro Sánchez

    2012-01-01

    Multicellular organisms are equipped with cellular mechanisms that enable them to replace differentiated cells lost to normal physiological turnover, injury, and for some such as planarians, even amputation. This process of tissue homeostasis is generally mediated by adult stem cells (ASCs), tissue-specific stem cells responsible for maintaining anatomical form and function. To do so, ASCs must modulate the balance between cell proliferation, i.e. in response to nutrients, and that of cell death, i.e. in response to starvation or injury. But how these two antagonistic processes are coordinated remains unclear. Here, we explore the role of the core components of the TOR pathway during planarian tissue homeostasis and regeneration and identified an essential function for TORC1 in these two processes. RNAi-mediated silencing of TOR in intact animals resulted in a significant increase in cell death, whereas stem cell proliferation and stem cell maintenance were unaffected. Amputated animals failed to increase stem cell proliferation after wounding and displayed defects in tissue remodeling. Together, our findings suggest two distinct roles for TORC1 in planarians. TORC1 is required to modulate the balance between cell proliferation and cell death during normal cell turnover and in response to nutrients. In addition, it is required to initiate appropriate stem cell proliferation during regeneration and for proper tissue remodeling to occur to maintain scale and proportion. PMID:22445864

  1. Connective Tissue Growth Factor Promotes Efficient Generation of Human Induced Pluripotent Stem Cell‐Derived Choroidal Endothelium

    PubMed Central

    Songstad, Allison E.; Worthington, Kristan S.; Chirco, Kathleen R.; Giacalone, Joseph C.; Whitmore, S. Scott; Anfinson, Kristin R.; Ochoa, Dalyz; Cranston, Cathryn M.; Riker, Megan J.; Neiman, Maurine; Stone, Edwin M.; Mullins, Robert F.

    2017-01-01

    Abstract Age‐related macular degeneration (AMD) is a leading cause of irreversible blindness in the Western world. Although, the majority of stem cell research to date has focused on production of retinal pigment epithelial (RPE) and photoreceptor cells for the purpose of evaluating disease pathophysiology and cell replacement, there is strong evidence that the choroidal endothelial cells (CECs) that form the choriocapillaris vessels are the first to be lost in this disease. As such, to accurately evaluate disease pathophysiology and develop an effective treatment, production of patient‐specific, stem cell‐derived CECs will be required. In this study, we report for the first time a stepwise differentiation protocol suitable for generating human iPSC‐derived CEC‐like cells. RNA‐seq analysis of the monkey CEC line, RF/6A, combined with two statistical screens allowed us to develop media comprised of various protein combinations. In both screens, connective tissue growth factor (CTGF) was identified as the key component required for driving CEC development. A second factor tumor necrosis factor (TNF)‐related weak inducer of apoptosis receptor was also found to promote iPSC to CEC differentiation by inducing endogenous CTGF secretion. CTGF‐driven iPSC‐derived CEC‐like cells formed capillary tube‐like vascular networks, and expressed the EC‐specific markers CD31, ICAM1, PLVAP, vWF, and the CEC‐restricted marker CA4. In combination with RPE and photoreceptor cells, patient‐specific iPSC derived CEC‐like cells will enable scientists to accurately evaluate AMD pathophysiology and develop effective cell replacement therapies. Stem Cells Translational Medicine 2017;6:1533–1546 PMID:28474838

  2. [18F]FDG labeling of neural stem cells for in vivo cell tracking with positron emission tomography: inhibition of tracer release by phloretin.

    PubMed

    Stojanov, Katica; de Vries, Erik F J; Hoekstra, Dick; van Waarde, Aren; Dierckx, Rudi A J O; Zuhorn, Inge S

    2012-02-01

    The introduction of neural stem cells into the brain has promising therapeutic potential for the treatment of neurodegenerative diseases. To monitor the cellular replacement therapy, that is, to determine stem cell migration, survival, and differentiation, in vivo tracking methods are needed. Ideally, these tracking methods are noninvasive. Noninvasive tracking methods that have been successfully used for the visualization of blood-derived progenitor cells include magnetic resonance imaging and radionuclide imaging using single-photon emission computed tomography (SPECT) and positron emission tomography (PET). The SPECT tracer In-111-oxine is suitable for stem cell labeling, but for studies in small animals, the higher sensitivity and facile quantification that can be obtained with PET are preferred. Here the potential of 2'-[18F]fluoro-2'-deoxy-D-glucose ([18F]-FDG), a PET tracer, for tracking of neural stem cell (NSCs) trafficking toward an inflammation site was investigated. [18F]-FDG turns out to be a poor radiopharmaceutical to label NSCs owing to the low labeling efficiency and substantial release of radioactivity from these cells. Efflux of [18F]-FDG from NSCs can be effectively reduced by phloretin in vitro, but inhibition of tracer release is insufficient in vivo for accurate monitoring of stem cell trafficking.

  3. Restoring Ureagenesis in Hepatocytes by CRISPR/Cas9-mediated Genomic Addition to Arginase-deficient Induced Pluripotent Stem Cells.

    PubMed

    Lee, Patrick C; Truong, Brian; Vega-Crespo, Agustin; Gilmore, W Blake; Hermann, Kip; Angarita, Stephanie Ak; Tang, Jonathan K; Chang, Katherine M; Wininger, Austin E; Lam, Alex K; Schoenberg, Benjamen E; Cederbaum, Stephen D; Pyle, April D; Byrne, James A; Lipshutz, Gerald S

    2016-11-29

    Urea cycle disorders are incurable enzymopathies that affect nitrogen metabolism and typically lead to hyperammonemia. Arginase deficiency results from a mutation in Arg1, the enzyme regulating the final step of ureagenesis and typically results in developmental disabilities, seizures, spastic diplegia, and sometimes death. Current medical treatments for urea cycle disorders are only marginally effective, and for proximal disorders, liver transplantation is effective but limited by graft availability. Advances in human induced pluripotent stem cell research has allowed for the genetic modification of stem cells for potential cellular replacement therapies. In this study, we demonstrate a universally-applicable CRISPR/Cas9-based strategy utilizing exon 1 of the hypoxanthine-guanine phosphoribosyltransferase locus to genetically modify and restore arginase activity, and thus ureagenesis, in genetically distinct patient-specific human induced pluripotent stem cells and hepatocyte-like derivatives. Successful strategies restoring gene function in patient-specific human induced pluripotent stem cells may advance applications of genetically modified cell therapy to treat urea cycle and other inborn errors of metabolism.

  4. [Embryonic stem cells. Future perspectives].

    PubMed

    Groebner, M; David, R; Franz, W M

    2006-05-01

    Embryonic stem cells (ES cells) are able to differentiate into any cell type, and therefore represent an excellent source for cellular replacement therapies in the case of widespread diseases, for example heart failure, diabetes, Parkinson's disease and spinal cord injury. A major prerequisite for their efficient and safe clinical application is the availability of pure populations for direct cell transplantation or tissue engineering as well as the immunological compatibility of the transplanted cells. The expression of human surface markers under the control of cell type specific promoters represents a promising approach for the selection of cardiomyocytes and other cell types for therapeutic applications. The first human clinical trial using ES cells will start in the United States this year.

  5. Dental Mesenchymal Stem Cell-Based Translational Regenerative Dentistry: From Artificial to Biological Replacement

    PubMed Central

    Marei, Mona K.; El Backly, Rania M.

    2018-01-01

    Dentistry is a continuously changing field that has witnessed much advancement in the past century. Prosthodontics is that branch of dentistry that deals with replacing missing teeth using either fixed or removable appliances in an attempt to simulate natural tooth function. Although such “replacement therapies” appear to be easy and economic they fall short of ever coming close to their natural counterparts. Complications that arise often lead to failures and frequent repairs of such devices which seldom allow true physiological function of dental and oral-maxillofacial tissues. Such factors can critically affect the quality of life of an individual. The market for dental implants is continuously growing with huge economic revenues. Unfortunately, such treatments are again associated with frequent problems such as peri-implantitis resulting in an eventual loss or replacement of implants. This is particularly influential for patients having co-morbid diseases such as diabetes or osteoporosis and in association with smoking and other conditions that undoubtedly affect the final treatment outcome. The advent of tissue engineering and regenerative medicine therapies along with the enormous strides taken in their associated interdisciplinary fields such as stem cell therapy, biomaterial development, and others may open arenas to enhancing tissue regeneration via designing and construction of patient-specific biological and/or biomimetic substitutes. This review will overview current strategies in regenerative dentistry while overviewing key roles of dental mesenchymal stem cells particularly those of the dental pulp, until paving the way to precision/translational regenerative medicine therapies for future clinical use. PMID:29770323

  6. Graphene supports in vitro proliferation and osteogenic differentiation of goat adult mesenchymal stem cells: potential for bone tissue engineering.

    PubMed

    Elkhenany, Hoda; Amelse, Lisa; Lafont, Andersen; Bourdo, Shawn; Caldwell, Marc; Neilsen, Nancy; Dervishi, Enkeleda; Derek, Oshin; Biris, Alexandru S; Anderson, David; Dhar, Madhu

    2015-04-01

    Current treatments for bone loss injuries involve autologous and allogenic bone grafts, metal alloys and ceramics. Although these therapies have proved useful, they suffer from inherent challenges, and hence, an adequate bone replacement therapy has not yet been found. We hypothesize that graphene may be a useful nanoscaffold for mesenchymal stem cells and will promote proliferation and differentiation into bone progenitor cells. In this study, we evaluate graphene, a biocompatible inert nanomaterial, for its effect on in vitro growth and differentiation of goat adult mesenchymal stem cells. Cell proliferation and differentiation are compared between polystyrene-coated tissue culture plates and graphene-coated plates. Graphitic materials are cytocompatible and support cell adhesion and proliferation. Importantly, cells seeded on to oxidized graphene films undergo osteogenic differentiation in fetal bovine serum-containing medium without the addition of any glucocorticoid or specific growth factors. These findings support graphene's potential to act as an osteoinducer and a vehicle to deliver mesenchymal stem cells, and suggest that the combination of graphene and goat mesenchymal stem cells provides a promising construct for bone tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd.

  7. The Role of Stem Cells in the Treatment of Cerebral Palsy: a Review.

    PubMed

    Kiasatdolatabadi, Anahita; Lotfibakhshaiesh, Nasrin; Yazdankhah, Meysam; Ebrahimi-Barough, Somayeh; Jafarabadi, Mina; Ai, Arman; Sadroddiny, Esmaeil; Ai, Jafar

    2017-09-01

    Cerebral palsy (CP) is a neuromuscular disease due to injury in the infant's brain. The CP disorder causes many neurologic dysfunctions in the patient. Various treatment methods have been used for the management of CP disorder. However, there has been no absolute cure for this condition. Furthermore, some of the procedures which are currently used for relief of symptoms in CP cause discomfort or side effects in the patient. Recently, stem cell therapy has attracted a huge interest as a new therapeutic method for treatment of CP. Several investigations in animal and human with CP have demonstrated positive potential of stem cell transplantation for the treatment of CP disorder. The ultimate goal of this therapeutic method is to harness the regenerative capacity of the stem cells causing a formation of new tissues to replace the damaged tissue. During the recent years, there have been many investigations on stem cell therapy. However, there are still many unclear issues regarding this method and high effort is needed to create a technology as a perfect treatment. This review will discuss the scientific background of stem cell therapy for cerebral palsy including evidences from current clinical trials.

  8. Stem cell therapy and its potential role in pituitary disorders.

    PubMed

    Lara-Velazquez, Montserrat; Akinduro, Oluwaseun O; Reimer, Ronald; Woodmansee, Whitney W; Quinones-Hinojosa, Alfredo

    2017-08-01

    The pituitary gland is one of the key components of the endocrine system. Congenital or acquired alterations can mediate destruction of cells in the gland leading to hormonal dysfunction. Even though pharmacological treatment for pituitary disorders is available, exogenous hormone replacement is neither curative nor sustainable. Thus, alternative therapies to optimize management and improve quality of life are desired. An alternative modality to re-establish pituitary function is to promote endocrine cell regeneration through stem cells that can be obtained from the pituitary parenchyma or pluripotent cells. Stem cell therapy has been successfully applied to a plethora of other disorders, and is a promising alternative to hormonal supplementation for resumption of normal hormone homeostasis. In this review, we describe the common causes for pituitary deficiencies and the advances in cellular therapy to restore the physiological pituitary function.

  9. Human adipose-derived stem cells (ADSC) and human periodontal ligament stem cells (PDLSC) as cellular substrates of a toxicity prediction assay.

    PubMed

    Corrêa, Natássia Caroline Resende; Kuligovski, Crisciele; Paschoal, Ariane Caroline Campos; Abud, Ana Paula Ressetti; Rebelatto, Carmen Lucia Kuniyoshi; Leite, Lidiane Maria Boldrini; Senegaglia, Alexandra Cristina; Dallagiovanna, Bruno; Aguiar, Alessandra Melo de

    2018-02-01

    With the increasing need to develop in vitro assays to replace animal use, human stem cell-derived methods are emerging and showing outstanding contributions to the toxicological screening of substances. Adult human stem cells such as adipose-derived stem cells (ADSC) and periodontal ligament stem cells (PDLSC) were used as cell substrates for a cytotoxicity assay and toxicity prediction using the neutral red uptake (NRU) assay. First, primary cell cultures from three independent donors, from each tissue source, were characterized as mesenchymal stem cells (MSC) by plastic adherence and appropriate immunophenotype for MSC markers (positive for CD90, CD73, and CD105 and negative for CD11b, CD34, CD45, HLADR, and CD19). Furthermore, ADSC and PDLSC were able to differentiate into adipocytes and osteoblasts when maintained under the same culture conditions previously established for the NRU assay. NRU assays for three reference test substances were performed. R 2 was higher than 0.85 for all conditions, showing the feasibility to calculate IC 50 values. The IC 50 values were then used to predict the LD 50 of the test substances, which were comparable to previous results and the ICCVAM standard test report. Primary ADSC and PDLSC showed the potential to be considered as additional models for use in cytotoxicity assays. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. The human urothelium consists of multiple clonal units, each maintained by a stem cell.

    PubMed

    Gaisa, Nadine T; Graham, Trevor A; McDonald, Stuart A C; Cañadillas-Lopez, Sagrario; Poulsom, Richard; Heidenreich, Axel; Jakse, Gerhard; Tadrous, Paul J; Knuechel, Ruth; Wright, Nicholas A

    2011-10-01

    Little is known about the clonal architecture of human urothelium. It is likely that urothelial stem cells reside within the basal epithelial layer, yet lineage tracing from a single stem cell as a means to show the presence of a urothelial stem cell has never been performed. Here, we identify clonally related cell areas within human bladder mucosa in order to visualize epithelial fields maintained by a single founder/stem cell. Sixteen frozen cystectomy specimens were serially sectioned. Patches of cells deficient for the mitochondrially encoded enzyme cytochrome c oxidase (CCO) were identified using dual-colour enzyme histochemistry. To show that these patches represent clonal proliferations, small CCO-proficient and -deficient areas were individually laser-capture microdissected and the entire mitochondrial genome (mtDNA) in each area was PCR amplified and sequenced to identify mtDNA mutations. Immunohistochemistry was performed for the different cell layers of the urothelium and adjacent mesenchyme. CCO-deficient patches could be observed in normal urothelium of all cystectomy specimens. The two-dimensional length of these negative patches varied from 2-3 cells (about 30 µm) to 4.7 mm. Each cell area within a CCO-deficient patch contained an identical somatic mtDNA mutation, indicating that the patch was a clonal unit. Patches contained all the mature cell differentiation stages present in the urothelium, suggesting the presence of a stem cell. Our results demonstrate that the normal mucosa of human bladder contains stem cell-derived clonal units that actively replenish the urothelium during ageing. The size of the clonal unit attributable to each stem cell was broadly distributed, suggesting replacement of one stem cell clone by another. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  11. Human Neural Stem Cell Transplantation Ameliorates Radiation-Induced Cognitive Dysfunction

    PubMed Central

    Acharya, Munjal M.; Christie, Lori-Ann; Lan, Mary L.; Giedzinski, Erich; Fike, John R.; Rosi, Susanna; Limoli, Charles L.

    2012-01-01

    Cranial radiotherapy induces progressive and debilitating declines in cognition that may, in part, be caused by the depletion of neural stem cells. The potential of using stem cell replacement as a strategy to combat radiation-induced cognitive decline was addressed by irradiating athymic nude rats followed 2 days later by intrahippocampal transplantation with human neural stem cells (hNSC). Measures of cognitive performance, hNSC survival, and phenotypic fate were assessed at 1 and 4 months after irradiation. Irradiated animals engrafted with hNSCs showed significantly less decline in cognitive function than irradiated, sham-engrafted animals and acted indistinguishably from unirradiated controls. Unbiased stereology revealed that 23% and 12% of the engrafted cells survived 1 and 4 months after transplantation, respectively. Engrafted cells migrated extensively, differentiated along glial and neuronal lineages, and expressed the activity-regulated cytoskeleton-associated protein (Arc), suggesting their capability to functionally integrate into the hippocampus. These data show that hNSCs afford a promising strategy for functionally restoring cognition in irradiated animals. PMID:21757460

  12. In vitro-microenvironment directs preconditioning of human chorion derived MSC promoting differentiation of OPC-like cells.

    PubMed

    Periasamy, Ramesh; Surbek, Daniel V; Schoeberlein, Andreina

    2018-06-01

    The loss of oligodendrocyte progenitor cells (OPC) is a hallmark of perinatal brain injury. Our aim was to develop an in vitro culture condition for human chorion-derived mesenchymal stem cells (MSC) that enhances their stem cell properties and their capability to differentiate towards OPC-like cells. MSC were grown either in serum replacement medium (SRM) or serum-containing medium (SM) and tested for their morphology, proliferation, secretome, migration, protein expression and differentiation into OPC-like cells. MSC cultured in SRM condition have distinct morphology/protein expression profile, increased cell proliferation/migration and capacity to differentiate into OPC-like cells. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. BONE MARROW MESENCHYMAL STEM CELLS ARE PROGENITORS IN VITRO FOR INNER EAR HAIR CELLS

    PubMed Central

    Jeon, Sang-Jun; Oshima, Kazuo; Heller, Stefan; Edge, Albert S.B.

    2011-01-01

    Stem cells have been demonstrated in the inner ear but they do not spontaneously divide to replace damaged sensory cells. Mesenchymal stem cells (MSC) from bone marrow have been reported to differentiate into multiple lineages including neurons, and we therefore asked whether MSCs could generate sensory cells. Overexpression of the prosensory transcription factor, Math1, in sensory epithelial precursor cells induced expression of myosin VIIa, espin, Brn3c, p27Kip, and jagged2, indicating differentiation to inner ear sensory cells. Some of the cells displayed F-actin positive protrusions in the morphology characteristic of hair cell stereociliary bundles. Hair cell markers were also induced by culture of mouse MSC-derived cells in contact with embryonic chick inner ear cells, and this induction was not due to a cell fusion event, because the chick hair cells could be identified with a chick-specific antibody and chick and mouse antigens were never found in the same cell. PMID:17113786

  14. Potential role of herbal remedies in stem cell therapy: proliferation and differentiation of human mesenchymal stromal cells.

    PubMed

    Udalamaththa, Vindya Lankika; Jayasinghe, Chanika Dilumi; Udagama, Preethi Vidya

    2016-08-11

    Stem cell therapy has revolutionized modern clinical therapy with the potential of stem cells to differentiate into many different cell types which may help to replace different cell lines of an organism. Innumerous trials are carried out to merge new scientific knowledge and techniques with traditional herbal extracts that may result in less toxic, affordable, and highly available natural alternative therapeutics. Currently, mesenchyamal stromal cell (MSC) lines are treated with individual and mixtures of crude herbal extracts, as well as with purified compounds from herbal extracts, to investigate the mechanisms and effects of these on stem cell growth and differentiation. Human MSCs (hMSCs) possess multilineage, i.e., osteogenic, neurogenic, adipogenic, chondrogenic, and myogenic, differentiation abilities. The proliferative and differentiation properties of hMSCs treated with herbal extracts have shown promise in diseases such as osteoporosis, neurodegenerative disorders, and other tissue degenerative disorders. Well characterized herbal extracts that result in increased rates of tissue regeneration may be used in both stem cell therapy and tissue engineering for replacement therapy, where the use of scaffolds and vesicles with enhanced attaching and proliferative properties could be highly advantageous in the latter. Although the clinical application of herbal extracts is still in progress due to the variability and complexity of bioactive constituents, standardized herbal preparations will strengthen their application in the clinical context. We have critically reviewed the proliferative and differentiation effects of individual herbal extracts on hMSCs mainly derived from bone marrow and elaborated on the plausible underlying mechanisms of action. To be fruitfully used in reparative and regenerative therapy, future directions in this area of study should (i) make use of hMSCs derived from different non-traditional sources, including medical waste material (umbilical cord, Wharton's jelly, and placenta), (ii) take account of the vast numbers of herbal extracts used in traditional medicine globally, and (iii) investigate the mechanisms and pathways of their effects on hMSCs.

  15. Neural stem cells for disease modeling of Wolman disease and evaluation of therapeutics.

    PubMed

    Aguisanda, Francis; Yeh, Charles D; Chen, Catherine Z; Li, Rong; Beers, Jeanette; Zou, Jizhong; Thorne, Natasha; Zheng, Wei

    2017-06-28

    Wolman disease (WD) is a rare lysosomal storage disorder that is caused by mutations in the LIPA gene encoding lysosomal acid lipase (LAL). Deficiency in LAL function causes accumulation of cholesteryl esters and triglycerides in lysosomes. Fatality usually occurs within the first year of life. While an enzyme replacement therapy has recently become available, there is currently no small-molecule drug treatment for WD. We have generated induced pluripotent stem cells (iPSCs) from two WD patient dermal fibroblast lines and subsequently differentiated them into neural stem cells (NSCs). The WD NSCs exhibited the hallmark disease phenotypes of neutral lipid accumulation, severely deficient LAL activity, and increased LysoTracker dye staining. Enzyme replacement treatment dramatically reduced the WD phenotype in these cells. In addition, δ-tocopherol (DT) and hydroxypropyl-beta-cyclodextrin (HPBCD) significantly reduced lysosomal size in WD NSCs, and an enhanced effect was observed in DT/HPBCD combination therapy. The results demonstrate that these WD NSCs are valid cell-based disease models with characteristic disease phenotypes that can be used to evaluate drug efficacy and screen compounds. DT and HPBCD both reduce LysoTracker dye staining in WD cells. The cells may be used to further dissect the pathology of WD, evaluate compound efficacy, and serve as a platform for high-throughput drug screening to identify new compounds for therapeutic development.

  16. Current focus of stem cell application in retinal repair

    PubMed Central

    Alonso-Alonso, María L; Srivastava, Girish K

    2015-01-01

    The relevance of retinal diseases, both in society’s economy and in the quality of people’s life who suffer with them, has made stem cell therapy an interesting topic for research. Embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs) and adipose derived mesenchymal stem cells (ADMSCs) are the focus in current endeavors as a source of different retinal cells, such as photoreceptors and retinal pigment epithelial cells. The aim is to apply them for cell replacement as an option for treating retinal diseases which so far are untreatable in their advanced stage. ESCs, despite the great potential for differentiation, have the dangerous risk of teratoma formation as well as ethical issues, which must be resolved before starting a clinical trial. iPSCs, like ESCs, are able to differentiate in to several types of retinal cells. However, the process to get them for personalized cell therapy has a high cost in terms of time and money. Researchers are working to resolve this since iPSCs seem to be a realistic option for treating retinal diseases. ADMSCs have the advantage that the procedures to obtain them are easier. Despite advancements in stem cell application, there are still several challenges that need to be overcome before transferring the research results to clinical application. This paper reviews recent research achievements of the applications of these three types of stem cells as well as clinical trials currently based on them. PMID:25914770

  17. Human skeletal muscle-derived stem cells retain stem cell properties after expansion in myosphere culture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wei, Yan; Department of Otolaryngology, Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guang Zhou; Li, Yuan

    2011-04-15

    Human skeletal muscle contains an accessible adult stem-cell compartment in which differentiated myofibers are maintained and replaced by a self-renewing stem cell pool. Previously, studies using mouse models have established a critical role for resident stem cells in skeletal muscle, but little is known about this paradigm in human muscle. Here, we report the reproducible isolation of a population of cells from human skeletal muscle that is able to proliferate for extended periods of time as floating clusters of rounded cells, termed 'myospheres' or myosphere-derived progenitor cells (MDPCs). The phenotypic characteristics and functional properties of these cells were determined usingmore » reverse transcription-polymerase chain reaction (RT-PCR), flow cytometry and immunocytochemistry. Our results showed that these cells are clonogenic, express skeletal progenitor cell markers Pax7, ALDH1, Myod, and Desmin and the stem cell markers Nanog, Sox2, and Oct3/4 significantly elevated over controls. They could be maintained proliferatively active in vitro for more than 20 weeks and passaged at least 18 times, despite an average donor-age of 63 years. Individual clones (4.2%) derived from single cells were successfully expanded showing clonogenic potential and sustained proliferation of a subpopulation in the myospheres. Myosphere-derived cells were capable of spontaneous differentiation into myotubes in differentiation media and into other mesodermal cell lineages in induction media. We demonstrate here that direct culture and expansion of stem cells from human skeletal muscle is straightforward and reproducible with the appropriate technique. These cells may provide a viable resource of adult stem cells for future therapies of disease affecting skeletal muscle or mesenchymal lineage derived cell types.« less

  18. [Stem Cells in the Brain of Mammals and Human: Fundamental and Applied Aspects].

    PubMed

    Aleksandrova, M A; Marey, M V

    2015-01-01

    Brain stem cells represent an extremely intriguing phenomenon. The aim of our review is to present an integrity vision of their role in the brain of mammals and humans, and their clinical perspectives. Over last two decades, investigations of biology of the neural stem cells produced significant changes in general knowledge about the processes of development and functioning of the brain. Researches on the cellular and molecular mechanisms of NSC differentiation and behavior led to new understanding of their involvement in learning and memory. In the regenerative medicine, original therapeutic approaches to neurodegenerative brain diseases have been elaborated due to fundamental achievements in this field. They are based on specific regenerative potential of neural stem cells and progenitor cells, which possess the ability to replace dead cells and express crucially significant biologically active factors that are missing in the pathological brain. For the needs of cell substitution therapy in the neural diseases, adequate methods of maintaining stem cells in culture and their differentiation into different types of neurons and glial cells, have been developed currently. The success of modern cellular technologies has significantly expanded the range of cells used for cell therapy. The near future may bring new perspective and distinct progress in brain cell therapy due to optimizing the cells types most promising for medical needs.

  19. Magneto-optical labeling of fetal neural stem cells for in vivo MRI tracking.

    PubMed

    Flexman, J A; Minoshima, S; Kim, Y; Cross, D J

    2006-01-01

    Neural stem cell therapy for neurological pathologies, such as Alzheimer's and Parkinson's disease, may delay the onset of symptoms, replace damaged neurons and/or support the survival of endogenous cells. Magnetic resonance imaging (MRI) can be used to track magnetically labeled cells in vivo to observe migration. Prior to transplantation, labeled cells must be characterized to show that they retain their intrinsic properties, such as cell proliferation into neurospheres in a supplemented environment. In vivo images must also be correlated to sensitive, histological markers. In this study, we show that fetus-derived neural stem cells can be co-labeled with superparamagnetic iron oxide and PKH26, a fluorescent dye. Labeled cells retain the ability to proliferate into neurospheres in culture, but labeling prevents neurospheres from merging in a non-adherent culture environment. After labeled NSCs were transplantation into the rat brain, their location and subsequent migration along the corpus callosum was detected using MRI. This study demonstrates an imaging paradigm with which to develop an in vivo assay for quantitatively evaluating fetal neural stem cell migration.

  20. Effects of milk replacer formulation on measures of mammary growth and composition in Holstein heifers.

    PubMed

    Daniels, K M; Capuco, A V; McGilliard, M L; James, R E; Akers, R M

    2009-12-01

    Overfeeding prepubertal heifers may impair mammary parenchymal growth and reduce milk production, but evidence suggests that increased intake of a high-protein milk replacer before weaning may be beneficial. This study was designed to evaluate effects of milk replacer (MR) composition on mass and composition of mammary parenchyma and fat pad, growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis gene expression, and putative mammary epithelial stem cells. Specifically, we hypothesized that positive effects of faster rates of gain during the preweaning period alter the development, persistence, or activity of populations of putative mammary epithelial stem cells, possibly through involvement of GH/IGF-I axis molecules. Twenty-four newborn heifers were fed 1 of 4 MR diets (n = 6/diet): control [20% crude protein (CP), 21% fat MR fed at 441 g of dry matter (DM)/d], high protein, low fat (28% CP, 20% fat MR fed at 951 g of DM/d), high protein, high fat (27% CP, 28% fat MR fed at 951 g of DM/d), and high protein, high fat+ (27% CP, 28% fat MR fed at 1,431 g of DM/d). Water and starter (20% CP, 1.43% fat) were offered ad libitum. Animals were killed on d 65 and mammary tissue was subjected to biochemical, molecular, and histological examination. No differences in mammary parenchymal mass or composition, with or without adjusting for empty body weight, were detected. Mass was increased and composition of the mammary fat pad was altered by nutrient intake. No diet differences in putative mammary epithelial stem cell abundance or abundance of transcripts for genes of the GH/IGF-I axis were detected. In this study, growth of the mammary epithelium, size of the mammary epithelial stem cell population, and components of the GH/IGF-I axis did not depend on diet. However, an underlying positive correlation between telomerase, a marker of mammary stem cells, and growth of the mammary parenchyma was detected. Implications of diet-induced effects on mammary fat pad and possible effects on subsequent development and function remain to be determined.

  1. Recent technological updates and clinical applications of induced pluripotent stem cells.

    PubMed

    Diecke, Sebastian; Jung, Seung Min; Lee, Jaecheol; Ju, Ji Hyeon

    2014-09-01

    Induced pluripotent stem cells (iPSCs) were first described in 2006 and have since emerged as a promising cell source for clinical applications. The rapid progression in iPSC technology is still ongoing and directed toward increasing the efficacy of iPSC production and reducing the immunogenic and tumorigenic potential of these cells. Enormous efforts have been made to apply iPSC-based technology in the clinic, for drug screening approaches and cell replacement therapy. Moreover, disease modeling using patient-specific iPSCs continues to expand our knowledge regarding the pathophysiology and prospective treatment of rare disorders. Furthermore, autologous stem cell therapy with patient-specific iPSCs shows great propensity for the minimization of immune reactions and the provision of a limitless supply of cells for transplantation. In this review, we discuss the recent updates in iPSC technology and the use of iPSCs in disease modeling and regenerative medicine.

  2. Exosome-Like Vesicles Derived from Adipose Tissue Provide Biochemical Cues for Adipose Tissue Regeneration.

    PubMed

    Dai, Minjia; Yu, Mei; Zhang, Yan; Tian, Weidong

    2017-11-01

    There is an emerging need for soft tissue replacements in the field of reconstructive surgery for the treatment of congenital deformities, posttraumatic repair, and cancer rehabilitation. Previous studies have shown that the bioactive adipose tissue extract can induce adipogenesis without additional stem cells or growth factors. In this study, we innovatively investigated whether exosome-like vesicles derived from adipose tissue (ELV-AT) could direct stem cell differentiation and trigger adipose tissue regeneration. In vitro, ELV-AT can induce adipogenesis of adipose-derived stem cells and promote proliferation, migration, and angiogenic potential of the aorta endothelial cells. In vivo, ELV-AT were transplanted to a chamber on the back of nude mice and neoadipose tissues were formed. Our findings indicated that ELV-AT could be used as a cell-free therapeutic approach for adipose tissue regeneration.

  3. Stem cell research in pakistan; past, present and future.

    PubMed

    Zahra, Sayeda Anum; Muzavir, Sayed Raheel; Ashraf, Sadia; Ahmad, Aftab

    2015-05-01

    Stem cells have proved to have great therapeutic potential as stem cell treatment is replacing traditional ways of treatment in different disorders like cancer, aplastic anemia, stroke, heart disorders. The developed and developing countries are investing differently in this area of research so research output and clinical translation of research greatly vary among developed and developing countries. Present study was done to investigate the current status of stem cells research in Pakistan and ways to improve it. Many advanced countries (USA, UK and Canada etc.) are investing heavily in stem cell research and treatment. Different developing countries like Iran, Turkey and India are also following the developed countries and investing a lot in stem cells research. Pakistan is also making efforts in establishing this field to get desired benefits but unfortunately the progress is at very low pace. If Government plays an active role along with private sector, stem cell research in Pakistan can be boosted up. The numbers of publications from Pakistan are very less compared to developed and neighboring countries and Pakistan also has very less number of institutes working in this area of research. Stem cells research is at its initial stages in Pakistan and there is great need to bring Government, academia and industry together so they could make serious efforts to promote research in this very important field. This will help millions of patients suffering from incurable disorders and will also reduce economic loss.

  4. Extracellular Vesicles from Neural Stem Cells Transfer IFN-γ via Ifngr1 to Activate Stat1 Signaling in Target Cells

    PubMed Central

    Cossetti, Chiara; Iraci, Nunzio; Mercer, Tim R.; Leonardi, Tommaso; Alpi, Emanuele; Drago, Denise; Alfaro-Cervello, Clara; Saini, Harpreet K.; Davis, Matthew P.; Schaeffer, Julia; Vega, Beatriz; Stefanini, Matilde; Zhao, CongJian; Muller, Werner; Garcia-Verdugo, Jose Manuel; Mathivanan, Suresh; Bachi, Angela; Enright, Anton J.; Mattick, John S.; Pluchino, Stefano

    2015-01-01

    SUMMARY The idea that stem cell therapies work only via cell replacement is challenged by the observation of consistent intercellular molecule exchange between the graft and the host. Here we defined a mechanism of cellular signaling by which neural stem/precursor cells (NPCs) communicate with the microenvironment via extracellular vesicles (EVs), and we elucidated its molecular signature and function. We observed cytokine-regulated pathways that sort proteins and mRNAs into EVs. We described induction of interferon gamma (IFN-γ) pathway in NPCs exposed to proinflammatory cytokines that is mirrored in EVs. We showed that IFN-γ bound to EVs through Ifngr1 activates Stat1 in target cells. Finally, we demonstrated that endogenous Stat1 and Ifngr1 in target cells are indispensable to sustain the activation of Stat1 signaling by EV-associated IFN-γ/Ifngr1 complexes. Our study identifies a mechanism of cellular signaling regulated by EV-associated IFN-γ/Ifngr1 complexes, which grafted stem cells may use to communicate with the host immune system. PMID:25242146

  5. Induced pluripotent stem (iPS) cells: a new source for cell-based therapeutics?

    PubMed

    de Lázaro, Irene; Yilmazer, Açelya; Kostarelos, Kostas

    2014-07-10

    The generation of induced pluripotent stem (iPS) cells from somatic cells by the ectopic expression of defined transcription factors has provided the regenerative medicine field with a new tool for cell replacement strategies. The advantages that these pluripotent cells can offer in comparison to other sources of stem cells include the generation of patient-derived cells and the lack of embryonic tissue while maintaining a versatile differentiation potential. The promise of iPS cell derivatives for therapeutic applications is encouraging albeit very early in development, with the first clinical study currently ongoing in Japan. Many challenges are yet to be circumvented before this technology can be clinically translated widely though. The delivery and expression of the reprogramming factors, the genomic instability, epigenetic memory and impact of cell propagation in culture are only some of the concerns. This article aims to critically discuss the potential of iPS cells as a new source of cell therapeutics. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Letermovir Injection

    MedlinePlus

    ... in certain people who have received a hematopoietic stem-cell transplant (HSCT; a procedure that replaces diseased bone ... any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each ...

  7. In Vitro Expanded Stem Cells from the Developing Retina Fail to Generate Photoreceptors but Differentiate into Myelinating Oligodendrocytes

    PubMed Central

    Czekaj, Magdalena; Haas, Jochen; Gebhardt, Marlen; Müller-Reichert, Thomas; Humphries, Peter; Farrar, Jane; Bartsch, Udo; Ader, Marius

    2012-01-01

    Cell transplantation to treat retinal degenerative diseases represents an option for the replacement of lost photoreceptor cells. In vitro expandable cells isolated from the developing mammalian retina have been suggested as a potential source for the generation of high numbers of donor photoreceptors. In this study we used standardized culture conditions based on the presence of the mitogens FGF-2 and EGF to generate high numbers of cells in vitro from the developing mouse retina. These presumptive ‘retinal stem cells’ (‘RSCs’) can be propagated as monolayer cultures over multiple passages, express markers of undifferentiated neural cells, and generate neuronal and glial cell types upon withdrawal of mitogens in vitro or following transplantation into the adult mouse retina. The proportion of neuronal differentiation can be significantly increased by stepwise removal of mitogens and inhibition of the notch signaling pathway. However, ‘RSCs’, by contrast to their primary counterparts in vivo, i.e. retinal progenitor cells, loose the expression of retina-specific progenitor markers like Rax and Chx10 after passaging and fail to differentiate into photoreceptors both in vitro or after intraretinal transplantation. Notably, ‘RSCs’ can be induced to differentiate into myelinating oligodendrocytes, a cell type not generated by primary retinal progenitor cells. Based on these findings we conclude that ‘RSCs’ expanded in high concentrations of FGF-2 and EGF loose their retinal identity and acquire features of in vitro expandable neural stem-like cells making them an inappropriate cell source for strategies aimed at replacing photoreceptor cells in the degenerated retina. PMID:22848612

  8. Continuous development precludes radioprotection in a colonial ascidian.

    PubMed

    Laird, Diana J; Weissman, Irving L

    2004-03-01

    Colonial organisms provide a unique experimental system for stem cell biology. The colonial Urochordate Botryllus schlosseri reproduces sexually as well as by continuous asexual budding. Adjacent colonies with a shared histocompatibility allele undergo vascular fusion and establish a common blood circulation, performing natural transplantation. Fused colonies become chimeras, often with complete somatic replacement of the host cell genotype by the fused parabiont. We attempted to establish a radioprotection assay for the somatic stem cells that induce long-term chimerism in Botryllus. We demonstrate over a range of radiation doses that neither autologous nor allogeneic cell transplantation enhances survival of host colonies. This suggests that high mitotic index associated with continuous asexual development leads to radiosensitivity of organs and structures essential to survival during engraftment. We observe that radiation induces uncontrolled epithelial cell proliferation in abnormally terminated buds, suggesting that stem cells are not required for the initial stages of bud development.

  9. Cell-Imprinted Substrates Modulate Differentiation, Redifferentiation, and Transdifferentiation.

    PubMed

    Bonakdar, Shahin; Mahmoudi, Morteza; Montazeri, Leila; Taghipoor, Mojtaba; Bertsch, Arnaud; Shokrgozar, Mohammad Ali; Sharifi, Shahriar; Majidi, Mohammad; Mashinchian, Omid; Hamrang Sekachaei, Mohammad; Zolfaghari, Pegah; Renaud, Philippe

    2016-06-08

    Differentiation of stem cells into mature cells through the use of physical approaches is of great interest. Here, we prepared smart nanoenvironments by cell-imprinted substrates based on chondrocytes, tenocytes, and semifibroblasts as templates and demonstrated their potential for differentiation, redifferentiation, and transdifferentiation. Analysis of shape and upregulation/downregulation of specific genes of stem cells, which were seeded on these cell-imprinted substrates, confirmed that imprinted substrates have the capability to induce specific shapes and molecular characteristics of the cell types that were used as templates for cell-imprinting. Interestingly, immunofluorescent staining of a specific protein in chondrocytes (i.e., collagen type II) confirmed that adipose-derived stem cells, semifibroblasts, and tenocytes can acquire the chondrocyte phenotype after a 14 day culture on chondrocyte-imprinted substrates. In summary, we propose that common polystyrene tissue culture plates can be replaced by this imprinting technique as an effective and promising way to regulate any cell phenotype in vitro with significant potential applications in regenerative medicine and cell-based therapies.

  10. Repairing the vibratory vocal fold.

    PubMed

    Long, Jennifer L

    2018-01-01

    A vibratory vocal fold replacement would introduce a new treatment paradigm for structural vocal fold diseases such as scarring and lamina propria loss. This work implants a tissue-engineered replacement for vocal fold lamina propria and epithelium in rabbits and compares histology and function to injured controls and orthotopic transplants. Hypotheses were that the cell-based implant would engraft and control the wound response, reducing fibrosis and restoring vibration. Translational research. Rabbit adipose-derived mesenchymal stem cells (ASC) were embedded within a three-dimensional fibrin gel, forming the cell-based outer vocal fold replacement (COVR). Sixteen rabbits underwent unilateral resection of vocal fold epithelium and lamina propria, as well as reconstruction with one of three treatments: fibrin glue alone with healing by secondary intention, replantation of autologous resected vocal fold cover, or COVR implantation. After 4 weeks, larynges were examined histologically and with phonation. Fifteen rabbits survived. All tissues incorporated well after implantation. After 1 month, both graft types improved histology and vibration relative to injured controls. Extracellular matrix (ECM) of the replanted mucosa was disrupted, and ECM of the COVR implants remained immature. Immune reaction was evident when male cells were implanted into female rabbits. Best histologic and short-term vibratory outcomes were achieved with COVR implants containing male cells implanted into male rabbits. Vocal fold cover replacement with a stem cell-based tissue-engineered construct is feasible and beneficial in acute rabbit implantation. Wound-modifying behavior of the COVR implant is judged to be an important factor in preventing fibrosis. NA. Laryngoscope, 128:153-159, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  11. Circumferential Esophageal Replacement by a Tissue-engineered Substitute Using Mesenchymal Stem Cells

    PubMed Central

    Catry, Jonathan; Luong-Nguyen, Minh; Arakelian, Lousineh; Poghosyan, Tigran; Bruneval, Patrick; Domet, Thomas; Michaud, Laurent; Sfeir, Rony; Gottrand, Frederic; Larghero, Jerome; Vanneaux, Valerie

    2018-01-01

    Tissue engineering appears promising as an alternative technique for esophageal replacement. Mesenchymal stem cells (MSCs) could be of interest for esophageal regeneration. Evaluation of the ability of an acellular matrix seeded with autologous MSCs to promote tissue remodeling toward an esophageal phenotype after circumferential replacement of the esophagus in a mini pig model. A 3 cm long circumferential replacement of the abdominal esophagus was performed with an MSC-seeded matrix (MSC group, n = 10) versus a matrix alone (control group, n = 10), which has previously been matured into the great omentum. The graft area was covered with an esophageal removable stent. A comparative histological analysis of the graft area after animals were euthanized sequentially is the primary outcome of the study. Histological findings after maturation, overall animal survival, and postoperative morbidity were also compared between groups. At postoperative day 45 (POD 45), a mature squamous epithelium covering the entire surface of the graft area was observed in all the MSC group specimens but in none of the control group before POD 95. Starting at POD 45, desmin positive cells were seen in the graft area in the MSC group but never in the control group. There were no differences between groups in the incidence of surgical complications and postoperative death. In this model, MSCs accelerate the mature re-epitheliazation and early initiation of muscle cell colonization. Further studies will focus on the use of cell tracking tools in order to analyze the becoming of these cells and the mechanisms involved in this tissue regeneration. PMID:29390879

  12. Vascular Wall-Resident Multipotent Stem Cells of Mesenchymal Nature within the Process of Vascular Remodeling: Cellular Basis, Clinical Relevance, and Implications for Stem Cell Therapy.

    PubMed

    Klein, Diana

    2016-01-01

    Until some years ago, the bone marrow and the endothelial cell compartment lining the vessel lumen (subendothelial space) were thought to be the only sources providing vascular progenitor cells. Now, the vessel wall, in particular, the vascular adventitia, has been established as a niche for different types of stem and progenitor cells with the capacity to differentiate into both vascular and nonvascular cells. Herein, vascular wall-resident multipotent stem cells of mesenchymal nature (VW-MPSCs) have gained importance because of their large range of differentiation in combination with their distribution throughout the postnatal organism which is related to their existence in the adventitial niche, respectively. In general, mesenchymal stem cells, also designated as mesenchymal stromal cells (MSCs), contribute to the maintenance of organ integrity by their ability to replace defunct cells or secrete cytokines locally and thus support repair and healing processes of the affected tissues. This review will focus on the central role of VW-MPSCs within vascular reconstructing processes (vascular remodeling) which are absolute prerequisite to preserve the sensitive relationship between resilience and stability of the vessel wall. Further, a particular advantage for the therapeutic application of VW-MPSCs for improving vascular function or preventing vascular damage will be discussed.

  13. Is there a place for human fetal-derived stem cells for cell replacement therapy in Huntington's disease?

    PubMed

    Precious, Sophie V; Zietlow, Rike; Dunnett, Stephen B; Kelly, Claire M; Rosser, Anne E

    2017-06-01

    Huntington's disease (HD) is a neurodegenerative disease that offers an excellent paradigm for cell replacement therapy because of the associated relatively focal cell loss in the striatum. The predominant cells lost in this condition are striatal medium spiny neurons (MSNs). Transplantation of developing MSNs taken from the fetal brain has provided proof of concept that donor MSNs can survive, integrate and bring about a degree of functional recovery in both pre-clinical studies and in a limited number of clinical trials. The scarcity of human fetal tissue, and the logistics of coordinating collection and dissection of tissue with neurosurgical procedures makes the use of fetal tissue for this purpose both complex and limiting. Alternative donor cell sources which are expandable in culture prior to transplantation are currently being sought. Two potential donor cell sources which have received most attention recently are embryonic stem (ES) cells and adult induced pluripotent stem (iPS) cells, both of which can be directed to MSN-like fates, although achieving a genuine MSN fate has proven to be difficult. All potential donor sources have challenges in terms of their clinical application for regenerative medicine, and thus it is important to continue exploring a wide variety of expandable cells. In this review we discuss two less well-reported potential donor cell sources; embryonic germ (EG) cells and fetal neural precursors (FNPs), both are which are fetal-derived and have some properties that could make them useful for regenerative medicine applications. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. c-Kit-positive cardiac stem cells nested in hypoxic niches are activated by stem cell factor reversing the aging myopathy.

    PubMed

    Sanada, Fumihiro; Kim, Junghyun; Czarna, Anna; Chan, Noel Yan-Ki; Signore, Sergio; Ogórek, Barbara; Isobe, Kazuya; Wybieralska, Ewa; Borghetti, Giulia; Pesapane, Ada; Sorrentino, Andrea; Mangano, Emily; Cappetta, Donato; Mangiaracina, Chiara; Ricciardi, Mario; Cimini, Maria; Ifedigbo, Emeka; Perrella, Mark A; Goichberg, Polina; Choi, Augustine M; Kajstura, Jan; Hosoda, Toru; Rota, Marcello; Anversa, Piero; Leri, Annarosa

    2014-01-03

    Hypoxia favors stem cell quiescence, whereas normoxia is required for stem cell activation, but whether cardiac stem cell (CSC) function is regulated by the hypoxic/normoxic state of the cell is currently unknown. A balance between hypoxic and normoxic CSCs may be present in the young heart, although this homeostatic control may be disrupted with aging. Defects in tissue oxygenation occur in the old myocardium, and this phenomenon may expand the pool of hypoxic CSCs, which are no longer involved in myocyte renewal. Here, we show that the senescent heart is characterized by an increased number of quiescent CSCs with intact telomeres that cannot re-enter the cell cycle and form a differentiated progeny. Conversely, myocyte replacement is controlled only by frequently dividing CSCs with shortened telomeres; these CSCs generate a myocyte population that is chronologically young but phenotypically old. Telomere dysfunction dictates their actual age and mechanical behavior. However, the residual subset of quiescent young CSCs can be stimulated in situ by stem cell factor reversing the aging myopathy. Our findings support the notion that strategies targeting CSC activation and growth interfere with the manifestations of myocardial aging in an animal model. Although caution has to be exercised in the translation of animal studies to human beings, our data strongly suggest that a pool of functionally competent CSCs persists in the senescent heart and that this stem cell compartment can promote myocyte regeneration effectively, partly correcting the aging myopathy.

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

    PubMed

    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.

  16. Liver‐Directed Human Amniotic Epithelial Cell Transplantation Improves Systemic Disease Phenotype in Hurler Syndrome Mouse Model

    PubMed Central

    Rodriguez, Natalie S.; Yanuaria, Lisa; Parducho, Kevin Murphy R.; Garcia, Irving M.; Varghese, Bino A.; Grubbs, Brendan H.

    2017-01-01

    Abstract Mucopolysaccharidosis type 1 (MPS1) is an inherited lysosomal storage disorder caused by a deficiency in the glycosaminoglycan (GAG)‐degrading enzyme α‐l‐iduronidase (IDUA). In affected patients, the systemic accumulation of GAGs results in skeletal dysplasia, neurological degeneration, multiple organ dysfunction, and early death. Current therapies, including enzyme replacement and bone marrow transplant, improve life expectancy but the benefits to skeletal and neurological phenotypes are limited. In this study, we tested the therapeutic efficacy of liver‐directed transplantation of a placental stem cell, which possesses multilineage differentiation potential, low immunogenicity, and high lysosomal enzyme activity. Unfractionated human amniotic epithelial cells (hAECs) were transplanted directly into the liver of immunodeficient Idua knockout mouse neonates. The hAECs engraftment was immunohistochemically confirmed with anti‐human mitochondria staining. Enzyme activity assays indicated that hAECs transplantation restored IDUA function in the liver and significantly decreased urinary GAG excretion. Histochemical and micro‐computed tomography analyses revealed reduced GAG deposition in the phalanges joints and composition/morphology improvement of cranial and facial bones. Neurological assessment in the hAEC treated mice showed significant improvement of sensorimotor coordination in the hAEC treated mice compared to untreated mice. Results confirm that partial liver cell replacement with placental stem cells can provide long‐term (>20 weeks) and systemic restoration of enzyme function, and lead to significant phenotypic improvement in the MPS1 mouse model. This preclinical data indicate that liver‐directed placental stem cell transplantation may improve skeletal and neurological phenotypes of MPS1 patients. Stem Cells Translational Medicine 2017;6:1583–1594 PMID:28585336

  17. Slow cycling cells in the continuous dental lamina of Scyliorhinus canicula: new evidence for stem cells in sharks.

    PubMed

    Vandenplas, Sam; Vandeghinste, Robbe; Boutet, Agnes; Mazan, Sylvie; Huysseune, Ann

    2016-05-01

    In the lesser spotted catshark (Scyliorhinus canicula), as in most non-mammalian vertebrates, the dentition renews throughout life. To contribute to our understanding of how continuous tooth replacement is achieved, we searched for evidence for the presence of stem cells in this species. Three-dimensional reconstructions of juvenile (2-3 weeks post-hatch) specimens showed that tooth families merge imperceptibly with so-called interdental zones within a continuous and permanent dental lamina. Interdental regions are composed of three layers, continuous with cervical loop, middle, and outer dental epithelium of the tooth families, respectively. A BrdU pulse-chase experiment revealed that cell proliferation is initiated in the lingual part of the dental lamina and the resulting population shifts one tooth position towards the oral epithelium in around four to five weeks. In the longest chase time (114 days) label-retaining and arguably non-differentiated cells were present at the lingual border of the dental lamina. These were found in the outer and middle dental epithelium, both within and between tooth families. This area of the dental lamina did not show expression or distribution of Sox2. Our data support the hypothesis that stem cells reside at the lingual border of the continuous dental lamina, more specifically in the middle dental epithelium at the level of the tooth families, and in its extension between the tooth families. To demonstrate their true stemness and their role in continuous tooth replacement, it remains to be shown that these cells have the potential to give rise to a complete new successor. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. The molecular basis of neurosensory cell formation in ear development: a blueprint for hair cell and sensory neuron regeneration?

    PubMed Central

    Fritzsch, Bernd; Beisel, Kirk W.; Hansen, Laura

    2014-01-01

    Summary The inner ear of mammals uses neurosensory cells derived from the embryonic ear for mechanoelectric transduction of vestibular and auditory stimuli (the hair cells) and conducts this information to the brain via sensory neurons. As with most other neurons of mammals, lost hair cells and sensory neurons are not spontaneously replaced and result instead in age-dependent progressive hearing loss. We review the molecular basis of neurosensory development in the mouse ear to provide a blueprint for possible enhancement of therapeutically useful transformation of stem cells into lost neurosensory cells. We identify several readily available adult sources of stem cells that express, like the ectoderm-derived ear, genes known to be essential for ear development. Use of these stem cells combined with molecular insights into neurosensory cell specification and proliferation regulation of the ear, might allow for neurosensory regeneration of mammalian ears in the near future. PMID:17120192

  19. Abnormalities in human pluripotent cells due to reprogramming mechanisms

    PubMed Central

    Ma, Hong; Morey, Robert; O’Neil, Ryan C.; He, Yupeng; Daughtry, Brittany; Schultz, Matthew D.; Hariharan, Manoj; Nery, Joseph R.; Castanon, Rosa; Sabatini, Karen; Thiagarajan, Rathi D.; Tachibana, Masahito; Kang, Eunju; Tippner-Hedges, Rebecca; Ahmed, Riffat; Gutierrez, Nuria Marti; Van Dyken, Crystal; Polat, Alim; Sugawara, Atsushi; Sparman, Michelle; Gokhale, Sumita; Amato, Paula; Wolf, Don P.; Ecker, Joseph R.; Laurent, Louise C.; Mitalipov, Shoukhrat

    2016-01-01

    Human pluripotent stem cells hold potential for regenerative medicine, but available cell types have significant limitations. Although embryonic stem cells (ES cells) from in vitro fertilized embryos (IVF ES cells) represent the ‘gold standard’, they are allogeneic to patients. Autologous induced pluripotent stem cells (iPS cells) are prone to epigenetic and transcriptional aberrations. To determine whether such abnormalities are intrinsic to somatic cell reprogramming or secondary to the reprogramming method, genetically matched sets of human IVF ES cells, iPS cells and nuclear transfer ES cells (NT ES cells) derived by somatic cell nuclear transfer (SCNT) were subjected to genome-wide analyses. Both NT ES cells and iPS cells derived from the same somatic cells contained comparable numbers of de novo copy number variations. In contrast, DNA methylation and transcriptome profiles of NT ES cells corresponded closely to those of IVF ES cells, whereas iPS cells differed and retained residual DNA methylation patterns typical of parental somatic cells. Thus, human somatic cells can be faithfully reprogrammed to pluripotency by SCNT and are therefore ideal for cell replacement therapies. PMID:25008523

  20. Concise Review: Kidney Generation with Human Pluripotent Stem Cells.

    PubMed

    Morizane, Ryuji; Miyoshi, Tomoya; Bonventre, Joseph V

    2017-11-01

    Chronic kidney disease (CKD) is a worldwide health care problem, resulting in increased cardiovascular mortality and often leading to end-stage kidney disease, where patients require kidney replacement therapies such as hemodialysis or kidney transplantation. Loss of functional nephrons contributes to the progression of CKD, which can be attenuated but not reversed due to inability to generate new nephrons in human adult kidneys. Human pluripotent stem cells (hPSCs), by virtue of their unlimited self-renewal and ability to differentiate into cells of all three embryonic germ layers, are attractive sources for kidney regenerative therapies. Recent advances in stem cell biology have identified key signals necessary to maintain stemness of human nephron progenitor cells (NPCs) in vitro, and led to establishment of protocols to generate NPCs and nephron epithelial cells from human fetal kidneys and hPSCs. Effective production of large amounts of human NPCs and kidney organoids will facilitate elucidation of developmental and pathobiological pathways, kidney disease modeling and drug screening as well as kidney regenerative therapies. We summarize the recent studies to induce NPCs and kidney cells from hPSCs, studies of NPC expansion from mouse and human embryonic kidneys, and discuss possible approaches in vivo to regenerate kidneys with cell therapies and the development of bioengineered kidneys. Stem Cells 2017;35:2209-2217. © 2017 AlphaMed Press.

  1. Mesenchymal stromal cells from human perinatal tissues: From biology to cell therapy

    PubMed Central

    Bieback, Karen; Brinkmann, Irena

    2010-01-01

    Cell-based regenerative medicine is of growing interest in biomedical research. The role of stem cells in this context is under intense scrutiny and may help to define principles of organ regeneration and develop innovative therapeutics for organ failure. Utilizing stem and progenitor cells for organ replacement has been conducted for many years when performing hematopoietic stem cell transplantation. Since the first successful transplantation of umbilical cord blood to treat hematological malignancies, non-hematopoietic stem and progenitor cell populations have recently been identified within umbilical cord blood and other perinatal and fetal tissues. A cell population entitled mesenchymal stromal cells (MSCs) emerged as one of the most intensely studied as it subsumes a variety of capacities: MSCs can differentiate into various subtypes of the mesodermal lineage, they secrete a large array of trophic factors suitable of recruiting endogenous repair processes and they are immunomodulatory. Focusing on perinatal tissues to isolate MSCs, we will discuss some of the challenges associated with these cell types concentrating on concepts of isolation and expansion, the comparison with cells derived from other tissue sources, regarding phenotype and differentiation capacity and finally their therapeutic potential. PMID:21607124

  2. Neuro-immune interactions of neural stem cell transplants: From animal disease models to human trials

    PubMed Central

    Cossetti, Chiara; Pluchino, Stefano

    2014-01-01

    Stem cell technology is a promising branch of regenerative medicine that is aimed at developing new approaches for the treatment of severely debilitating human diseases, including those affecting the central nervous system (CNS). Despite the increasing understanding of the mechanisms governing their biology, the application of stem cell therapeutics remains challenging. The initial idea that stem cell transplants work in vivo via the replacement of endogenous cells lost or damaged owing to disease has been challenged by accumulating evidence of their therapeutic plasticity. This new concept covers the remarkable immune regulatory and tissue trophic effects that transplanted stem cells exert at the level of the neural microenvironment to promote tissue healing via combination of immune modulatory and tissue protective actions, while retaining predominantly undifferentiated features. Among a number of promising candidate stem cell sources, neural stem/precursor cells (NPCs) are under extensive investigation with regard to their therapeutic plasticity after transplantation. The significant impact in vivo of experimental NPC therapies in animal models of inflammatory CNS diseases has raised great expectations that these stem cells, or the manipulation of the mechanisms behind their therapeutic impact, could soon be translated to human studies. This review aims to provide an update on the most recent evidence of therapeutically-relevant neuroimmune interactions following NPC transplants in animal models of multiple sclerosis, cerebral stroke and traumas of the spinal cord, and consideration of the forthcoming challenges related to the early translation of some of these exciting experimental outcomes into clinical medicines. PMID:23507035

  3. Neuro-immune interactions of neural stem cell transplants: from animal disease models to human trials.

    PubMed

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

    2014-10-01

    Stem cell technology is a promising branch of regenerative medicine that is aimed at developing new approaches for the treatment of severely debilitating human diseases, including those affecting the central nervous system (CNS). Despite the increasing understanding of the mechanisms governing their biology, the application of stem cell therapeutics remains challenging. The initial idea that stem cell transplants work in vivo via the replacement of endogenous cells lost or damaged owing to disease has been challenged by accumulating evidence of their therapeutic plasticity. This new concept covers the remarkable immune regulatory and tissue trophic effects that transplanted stem cells exert at the level of the neural microenvironment to promote tissue healing via combination of immune modulatory and tissue protective actions, while retaining predominantly undifferentiated features. Among a number of promising candidate stem cell sources, neural stem/precursor cells (NPCs) are under extensive investigation with regard to their therapeutic plasticity after transplantation. The significant impact in vivo of experimental NPC therapies in animal models of inflammatory CNS diseases has raised great expectations that these stem cells, or the manipulation of the mechanisms behind their therapeutic impact, could soon be translated to human studies. This review aims to provide an update on the most recent evidence of therapeutically-relevant neuro-immune interactions following NPC transplants in animal models of multiple sclerosis, cerebral stroke and traumas of the spinal cord, and consideration of the forthcoming challenges related to the early translation of some of these exciting experimental outcomes into clinical medicines. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Application of stem cell-derived retinal pigmented epithelium in retinal degenerative diseases: present and future.

    PubMed

    Luo, Mingyue; Chen, Youxin

    2018-01-01

    As a constituent of blood-retinal barrier and retinal outer segment (ROS) scavenger, retinal pigmented epithelium (RPE) is fundamental to normal function of retina. Malfunctioning of RPE contributes to the onset and advance of retinal degenerative diseases. Up to date, RPE replacement therapy is the only possible method to completely reverse retinal degeneration. Transplantation of human RPE stem cell-derived RPE (hRPESC-RPE) has shown some good results in animal models. With promising results in terms of safety and visual improvement, human embryonic stem cell-derived RPE (hESC-RPE) can be expected in clinical settings in the near future. Despite twists and turns, induced pluripotent stem cell-derived RPE (iPSC-RPE) is now being intensely investigated to overcome genetic and epigenetic instability. By far, only one patient has received iPSC-RPE transplant, which is a hallmark of iPSC technology development. During follow-up, no major complications such as immunogenicity or tumorigenesis have been observed. Future trials should keep focusing on the safety of stem cell-derived RPE (SC-RPE) especially in long period, and better understanding of the nature of stem cell and the molecular events in the process to generate SC-RPE is necessary to the prosperity of SC-RPE clinical application.

  5. The Use Of Laser Irradiation To Stimulate Adipose Derived Stem Cell Proliferation And Differentiation For Use In Autologous Grafts

    NASA Astrophysics Data System (ADS)

    Abrahamse, Heidi

    2009-09-01

    Stem cells are characterized by the qualities of self-renewal, long term viability, and the ability to differentiate into various cell types. Historically, stem cells have been isolated from the inner cell mass of blastocysts and harvesting these cells resulted in the death of the embryo leading to religious, political and ethical issues. The identification and subsequent isolation of adult stem cells from bone marrow stroma have been welcomed as an alternate source for stem cells. The clinical use of Mesenchymal Stem Cells (MSCs) presented problems such as limited cell number, pain and morbidity upon isolation. Adipose tissue is derived from the mesenchyme, is easily isolated, a reliable source of stem cells and able to differentiate into different cell types including smooth muscle. Over the past few years, the identification and characterization of stem cells has led the potential use of these cells as a promising alternative to cell replacement therapy. Smooth muscle is a major component of human tissues and is essential for the normal functioning of many different organs. Low intensity laser irradiation has been shown to increase viability, protein expression and migration of stem cells in vitro, and to stimulate proliferation of various types of stem cells. In addition, the use of laser irradiation to stimulate differentiation in the absence of growth factors has also been demonstrated in normal human neural progenitor cells (NHNPCs) in vitro where NHNPCs are not only capable of being sustained by light in the absence of growth factors, but that they are also able to differentiate normally as assessed by neurite formation. Our work has focused on the ability of laser irradiation to proliferate adipose derived stem cells (ADSCs), maintain ADSC character and increase the rate and maintenance of differentiation of ADSCs into smooth muscle and skin fibroblast cells. Current studies are also investigating the effect of different irradiation wavelengths and fluences on ADSC viability and proliferation. This paper reviews the development of MSCs as potential therapeutic interventions such as autologous grafts as well as the contribution of low intensity laser irradiation on the maintenance of these cells.

  6. Isolation, Characterization, Cryopreservation of Human Amniotic Stem Cells and Differentiation to Osteogenic and Adipogenic Cells

    PubMed Central

    Gholizadeh-Ghaleh Aziz, Shiva; Pashaei-Asl, Fatima; Fardyazar, Zahra; Pashaiasl, Maryam

    2016-01-01

    Human stem cells and progenitor cells can be used to treat cancer and replace dysfunctional cells within a tissue or organ. The objective of this study was to identify the appropriate cells type in regenerative medicine and targeted therapy. As an alternative to embryonic and bone marrow stem cells, we examined human amniotic fluid stem cells (hAFSCs), one of the potential source of multipotent stem cells isolated from both cell pellet (using single-stage method), and supernatant of human amniotic fluid. Source of isolation and unique property of the cells emphasize that these cells are one of the promising new tools in therapeutic field. Double sources for isolation and availability of the left over samples in diagnostic laboratory at the same time have less legal and ethical concerns compared with embryonic stem cell studies. Cells were isolated, cultured for 18th passage for 6 months and characterized using qPCR and flow cytometry. Cells showed good proliferative ability in culture condition. The cells successfully differentiated into the adipogenic and osteogenic lineages. Based on these findings, amniotic fluid can be considered as an appropriate and convenient source of human amniotic fluid stem cells. These cells provide potential tools for therapeutic applications in the field of regenerative medicine. To get a better understanding of crosstalk between Oct4/NANOG with osteogenesis and adipogenesis, we used network analysis based on Common Targets algorithm and Common Regulators algorithm as well as subnetwork discovery based on gene set enrichment. Network analysis highlighted the possible role of MIR 302A and MIR let-7g. We demonstrated the high expression of MIR 302A and low expression of MIR let7g in hAFSCs by qPCR. PMID:27434028

  7. Successful chondrogenesis within scaffolds, using magnetic stem cell confinement and bioreactor maturation.

    PubMed

    Luciani, Nathalie; Du, Vicard; Gazeau, Florence; Richert, Alain; Letourneur, Didier; Le Visage, Catherine; Wilhelm, Claire

    2016-06-01

    Tissue engineering strategies, such as cellularized scaffolds approaches, have been explored for cartilage replacement. The challenge, however, remains to produce a cartilaginous tissue incorporating functional chondrocytes and being large and thick enough to be compatible with the replacement of articular defects. Here, we achieved unprecedented cartilage tissue production into a porous polysaccharide scaffold by combining of efficient magnetic condensation of mesenchymal stem cells, and dynamic maturation in a bioreactor. In optimal conditions, all the hallmarks of chondrogenesis were enhanced with a 50-fold increase in collagen II expression compared to negative control, an overexpression of aggrecan and collagen XI, and a very low expression of collagen I and RUNX2. Histological staining showed a large number of cellular aggregates, as well as an increased proteoglycan synthesis by chondrocytes. Interestingly, electron microscopy showed larger chondrocytes and a more abundant extracellular matrix. In addition, the periodicity of the neosynthesized collagen fibers matched that of collagen II. These results represent a major step forward in replacement tissue for cartilage defects. A combination of several innovative technologies (magnetic cell seeding, polysaccharide porous scaffolds, and dynamic maturation in bioreactor) enabled unprecedented successful chondrogenesis within scaffolds. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  8. Will stem cell therapies be safe and effective for treating spinal cord injuries?

    PubMed Central

    Thomas, Katharine E.; Moon, Lawrence D. F.

    2017-01-01

    Introduction A large number of different cells including embryonic and adult stem cells have been transplanted into animal models of spinal cord injury, and in many cases these procedures have resulted in modest sensorimotor benefits. In October 2010 the world’s first clinical trial using human embryonic stem cells began, using stem cells converted into oligodendrocyte precursor cells. Sources of data In this review we examine some of the publically-available pre-clinical evidence that some of these cell types improve outcome in animal models of spinal cord injury. Much evidence is not available for public scrutiny, however, being private commercial property of various stem cell companies. Areas of agreement Transplantation of many different types of stem and progenitor cell enhances spontaneous recovery of function when transplanted acutely after spinal cord injury in animal models. Areas of disagreement The common mechanism(s) whereby the generic procedure of cellular transplantation enhances recovery of function are not well understood, although a range of possibilities are usually cited (including preservation of tissue, remyelination, axon sprouting, glial cell replacement). Only in exceptional cases has it been shown that functional recovery depends causally on the survival and differentiation of the transplanted cells. There is no agreement about the optimal cell type for transplantation: candidate stem cells have not yet been compared with each other or with other cell types (e.g., autologous Schwann cells) in a single study. Areas timely for developing research Transplantation of cells into animals with a long lifespan is important to determine whether or not tumours will eventually form. It will also be important to determine whether long-term survival of cells is required for functional recovery, and if so, how many are optimal. PMID:21586446

  9. Stem Cell Fate Determination during Development and Regeneration of Ectodermal Organs

    PubMed Central

    Jiménez-Rojo, Lucía; Granchi, Zoraide; Graf, Daniel; Mitsiadis, Thimios A.

    2012-01-01

    The development of ectoderm-derived appendages results in a large variety of highly specialized organs such as hair follicles, mammary glands, salivary glands, and teeth. Despite varying in number, shape, and function, all these ectodermal organs develop through continuous and reciprocal epithelial–mesenchymal interactions, sharing common morphological and molecular features especially during their embryonic development. Diseases such as ectodermal dysplasias can affect simultaneously these organs, suggesting that they may arise from common multipotent precursors residing in the embryonic ectoderm. During embryogenesis, these putative ectodermal stem cells may adopt different fates and consequently be able to generate a variety of tissue-specific stem cells, which are the sources for the various cell lineages that form the diverse organs. The specification of those common epithelial precursors, as well as their further lineage commitment to tissue-specific stem cells, might be controlled by specific signals. It has been well documented that Notch, Wnt, bone morphogenetic protein, and fibroblast growth factor signaling pathways regulate cell fate decisions during the various stages of ectodermal organ development. However, the in vivo spatial and temporal dynamics of these signaling pathways are not yet well understood. Improving the current knowledge on the mechanisms involved in stem cell fate determination during organogenesis and homeostasis of ectodermal organs is crucial to develop effective stem cell-based therapies in order to regenerate or replace pathological and damaged tissues. PMID:22539926

  10. Stem Cell Fate Determination during Development and Regeneration of Ectodermal Organs.

    PubMed

    Jiménez-Rojo, Lucía; Granchi, Zoraide; Graf, Daniel; Mitsiadis, Thimios A

    2012-01-01

    The development of ectoderm-derived appendages results in a large variety of highly specialized organs such as hair follicles, mammary glands, salivary glands, and teeth. Despite varying in number, shape, and function, all these ectodermal organs develop through continuous and reciprocal epithelial-mesenchymal interactions, sharing common morphological and molecular features especially during their embryonic development. Diseases such as ectodermal dysplasias can affect simultaneously these organs, suggesting that they may arise from common multipotent precursors residing in the embryonic ectoderm. During embryogenesis, these putative ectodermal stem cells may adopt different fates and consequently be able to generate a variety of tissue-specific stem cells, which are the sources for the various cell lineages that form the diverse organs. The specification of those common epithelial precursors, as well as their further lineage commitment to tissue-specific stem cells, might be controlled by specific signals. It has been well documented that Notch, Wnt, bone morphogenetic protein, and fibroblast growth factor signaling pathways regulate cell fate decisions during the various stages of ectodermal organ development. However, the in vivo spatial and temporal dynamics of these signaling pathways are not yet well understood. Improving the current knowledge on the mechanisms involved in stem cell fate determination during organogenesis and homeostasis of ectodermal organs is crucial to develop effective stem cell-based therapies in order to regenerate or replace pathological and damaged tissues.

  11. The advancement of human pluripotent stem cell-derived therapies into the clinic.

    PubMed

    Thies, R Scott; Murry, Charles E

    2015-09-15

    Human pluripotent stem cells (hPSCs) offer many potential applications for drug screening and 'disease in a dish' assay capabilities. However, a more ambitious goal is to develop cell therapeutics using hPSCs to generate and replace somatic cells that are lost as a result of disease or injury. This Spotlight article will describe the state of progress of some of the hPSC-derived therapeutics that offer the most promise for clinical use. Lessons from developmental biology have been instrumental in identifying signaling molecules that can guide these differentiation processes in vitro, and will be described in the context of these cell therapy programs. © 2015. Published by The Company of Biologists Ltd.

  12. Hedgehog Promotes Production of Inhibitory Interneurons in Vivo and in Vitro from Pluripotent Stem Cells

    PubMed Central

    Anderson, Nickesha C.; Chen, Christopher Y.; Grabel, Laura

    2016-01-01

    Loss or damage of cortical inhibitory interneurons characterizes a number of neurological disorders. There is therefore a great deal of interest in learning how to generate these neurons from a pluripotent stem cell source so they can be used for cell replacement therapies or for in vitro drug testing. To design a directed differentiation protocol, a number of groups have used the information gained in the last 15 years detailing the conditions that promote interneuron progenitor differentiation in the ventral telencephalon during embryogenesis. The use of Hedgehog peptides and agonists is featured prominently in these approaches. We review here the data documenting a role for Hedgehog in specifying interneurons in both the embryonic brain during development and in vitro during the directed differentiation of pluripotent stem cells. PMID:29615590

  13. 77 FR 12316 - Government-Owned Inventions; Availability for Licensing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-29

    ..., mobilizes hematopoietic stem/progenitor cells (HSPCs) from the bone marrow into blood. These mobilized HSPCs... bone marrow. miR126 may also facilitate mobilization of bone-resident cancer cells into the circulation where they could be more easily targeted by cancer therapeutics. This discovery could replace bone...

  14. Transplantation of embryonic stem cell-derived dopaminergic neurons in MPTP-treated monkeys.

    PubMed

    Takahashi, Jun; Takagi, Yasushi; Saiki, Hidemoto

    2009-01-01

    One of the target diseases of cell-replacement therapy is Parkinson's disease. Clinical experiences with fetal dopaminergic cell graft have shown that the therapy is effective, but limited and accompanied by side effects, such as dyskinesia. So, the therapy needs to be further improved and sophisticated. Embryonic stem (ES) cells are expected to be another donor cell for the treatment, because of its proliferative and differentiation capacities. For clinical application, experiments using non-human primates are important, because size, anatomy, and biological characteristics of the brain are different between rodents and primates. Here, we would like to discuss induction of dopaminergic neurons from monkey ES cells and cell transplantation into the brain of monkey Parkinson's disease model.

  15. The contribution of human/non-human animal chimeras to stem cell research.

    PubMed

    Levine, Sonya; Grabel, Laura

    2017-10-01

    Chimeric animals are made up of cells from two separate zygotes. Human/non-human animal chimeras have been used for a number of research purposes, including human disease modeling. Pluripotent stem cell (PSC) research has relied upon the chimera approach to examine the developmental potential of stem cells, to determine the efficacy of cell replacement therapies, and to establish a means of producing human organs. Based on ethical issues, this work has faced pushback from various sources including funding agencies. We discuss here the essential role these studies have played, from gaining a better understanding of human biology to providing a stepping stone to human disease treatments. We also consider the major ethical issues, as well as the current status of support for this work in the United States. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  16. Fetal Membranes-Derived Stem Cells Microenvironment.

    PubMed

    Favaron, Phelipe Oliveira; Miglino, Maria Angelica

    2017-01-01

    Recently, the regenerative medicine has been trying to congregate different areas such as tissue engineering and cellular therapy, in order to offer effective treatments to overcome several human and veterinary medical problems. In this regard, fetal membranes have been proposed as a powerful source for obtainment of multipotent stem cells with low immunogenicity, anti-inflammatory properties and nontumorigenicity properties for the treatment of several diseases, including replacing cells lost due to tissue injuries or degenerative diseases. Morpho-physiological data have shown that fetal membranes, especially the yolk sac and amnion play different functions according to the gestational period, which are direct related to the features of the microenvironment that their cells are subject. The characteristics of the microenvironment affect or controls important cellular events involved with proliferation, division and maintenance of the undifferentiated stage or differentiation, especially acting on the extracellular matrix components. Considering the importance of the microenvironment and the diversity of embryonic and fetal membrane-derived stem cells, this chapter will addressed advances in the isolation, phenotyping, characteristics of the microenvironment, and applications of yolk sac and amniotic membrane-derived stem cells for human and veterinary regenerative medicine.

  17. Serum-free cryopreservation of human amniotic epithelial cells before and after isolation from their natural scaffold.

    PubMed

    Niknejad, Hassan; Deihim, Tina; Peirovi, Habibollah; Abolghasemi, Hassan

    2013-08-01

    Amniotic epithelial cells are a promising source for stem cell-based therapy through their potential capacity to differentiate into the cell lineages of all three germ layers. Long-term preservation is necessary to have a ready-to-use source of stem cells, when required. Reduced differentiation capability, decrease of viability and use of fetal bovine serum (FBS) are three drawbacks of clinical application of cryopreserved stem cells. In this study, we used human amniotic fluid instead of animal serum, and evaluated viability and multipotency of amniotic epithelial cells after cryopreservation in suspension and compared with those cryopreserved on their natural scaffold (in situ cryopreservation). There was no significant difference in viability of the cells cryopreserved in amniotic fluid and FBS. Also, the same results were achieved for expression of pluripotency marker OCT-4 when FBS was replaced by amniotic fluid in the samples with the same cryoprotectant. The cells cryopreserved in presence of scaffold had a higher level of viability compared to the cells cryopreserved in suspension. Although, the number of the cells expressed OCT-4 significantly decreased within cryopreservation in suspension, no decrease in expression of OCT-4 was observed when the cells cryopreserved with their natural scaffold. Upon culturing of post-thawed cells in specific lineage differentiating mediums, the markers of neuronal, hepatic, cardiomyocytic and pancreatic were found in differentiated cells. These results show that replacement of FBS by amniotic fluid and in situ cryopreservation of amniotic epithelial cells is an effective approach to overcome limitations related to long-term preservation including differentiation during cryopreservation and decrease of viability. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Distal Regeneration Involves the Age Dependent Activity of Branchial Sac Stem Cells in the Ascidian Ciona intestinalis.

    PubMed

    Jeffery, William R

    2015-02-01

    Tunicates have high capacities for regeneration but the underlying mechanisms and their relationship to life cycle progression are not well understood. Here we investigate the regeneration of distal structures in the ascidian tunicate Ciona intestinalis . Analysis of regenerative potential along the proximal-distal body axis indicated that distal organs, such as the siphons, their pigmented sensory organs, and the neural complex, could only be replaced from body fragments containing the branchial sac. Distal regeneration involves the formation of a blastema composed of cells that undergo cell proliferation prior to differentiation and cells that differentiate without cell proliferation. Both cell types originate in the branchial sac and appear in the blastema at different times after distal injury. Whereas the branchial sac stem cells are present in young animals, they are depleted in old animals that have lost their regeneration capacity. Thus Ciona adults contain a population of age-related stem cells located in the branchial sac that are a source of precursors for distal body regeneration.

  19. Stromal Progenitor Cells in Mitigation of Non-Hematopoietic Radiation Injuries

    PubMed Central

    Kulkarni, Shilpa; Wang, Timothy C.; Guha, Chandan

    2016-01-01

    Purpose of review Therapeutic exposure to high doses of radiation can severely impair organ function due to ablation of stem cells. Normal tissue injury is a dose-limiting toxicity for radiation therapy (RT). Although advances in the delivery of high precision conformal RT has increased normal tissue sparing, mitigating and therapeutic strategies that could alleviate early and chronic radiation effects are urgently needed in order to deliver curative doses of RT, especially in abdominal, pelvic and thoracic malignancies. Radiation-induced gastrointestinal injury is also a major cause of lethality from accidental or intentional exposure to whole body irradiation in the case of nuclear accidents or terrorism. This review examines the therapeutic options for mitigation of non-hematopoietic radiation injuries. Recent findings We have developed stem cell based therapies for the mitigation of acute radiation syndrome (ARS) and radiation-induced gastrointestinal syndrome (RIGS). This is a promising option because of the robustness of standardized isolation and transplantation of stromal cells protocols, and their ability to support and replace radiation-damaged stem cells and stem cell niche. Stromal progenitor cells (SPC) represent a unique multipotent and heterogeneous cell population with regenerative, immunosuppressive, anti-inflammatory, and wound healing properties. SPC are also known to secrete various key cytokines and growth factors such as platelet derived growth factors (PDGF), keratinocyte growth factor (KGF), R-spondins (Rspo), and may consequently exert their regenerative effects via paracrine function. Additionally, secretory vesicles such as exosomes or microparticles can potentially be a cell-free alternative replacing the cell transplant in some cases. Summary This review highlights the beneficial effects of SPC on tissue regeneration with their ability to (a) target the irradiated tissues, (b) recruit host stromal cells, (c) regenerate endothelium and epithelium, (d) and secrete regenerative and immunomodulatory paracrine signals to control inflammation, ulceration, wound healing and fibrosis. PMID:28462013

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

    PubMed Central

    Merzaban, Jasmeen S; Imitola, Jaime; Starossom, Sarah C; Zhu, Bing; Wang, Yue; Lee, Jack; Ali, Amal J; Olah, Marta; Abuelela, Ayman F; Khoury, Samia J; Sackstein, Robert

    2015-01-01

    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. PMID:26153105

  1. Induced Pluripotent Stem Cells for Disease Modeling and Evaluation of Therapeutics for Niemann-Pick Disease Type A.

    PubMed

    Long, Yan; Xu, Miao; Li, Rong; Dai, Sheng; Beers, Jeanette; Chen, Guokai; Soheilian, Ferri; Baxa, Ulrich; Wang, Mengqiao; Marugan, Juan J; Muro, Silvia; Li, Zhiyuan; Brady, Roscoe; Zheng, Wei

    2016-12-01

    : Niemann-Pick disease type A (NPA) is a lysosomal storage disease caused by mutations in the SMPD1 gene that encodes acid sphingomyelinase (ASM). Deficiency in ASM function results in lysosomal accumulation of sphingomyelin and neurodegeneration. Currently, there is no effective treatment for NPA. To accelerate drug discovery for treatment of NPA, we generated induced pluripotent stem cells from two patient dermal fibroblast lines and differentiated them into neural stem cells. The NPA neural stem cells exhibit a disease phenotype of lysosomal sphingomyelin accumulation and enlarged lysosomes. By using this disease model, we also evaluated three compounds that reportedly reduced lysosomal lipid accumulation in Niemann-Pick disease type C as well as enzyme replacement therapy with ASM. We found that α-tocopherol, δ-tocopherol, hydroxypropyl-β-cyclodextrin, and ASM reduced sphingomyelin accumulation and enlarged lysosomes in NPA neural stem cells. Therefore, the NPA neural stem cells possess the characteristic NPA disease phenotype that can be ameliorated by tocopherols, cyclodextrin, and ASM. Our results demonstrate the efficacies of cyclodextrin and tocopherols in the NPA cell-based model. Our data also indicate that the NPA neural stem cells can be used as a new cell-based disease model for further study of disease pathophysiology and for high-throughput screening to identify new lead compounds for drug development. Currently, there is no effective treatment for Niemann-Pick disease type A (NPA). To accelerate drug discovery for treatment of NPA, NPA-induced pluripotent stem cells were generated from patient dermal fibroblasts and differentiated into neural stem cells. By using the differentiated NPA neuronal cells as a cell-based disease model system, α-tocopherol, δ-tocopherol, and hydroxypropyl-β-cyclodextrin significantly reduced sphingomyelin accumulation in these NPA neuronal cells. Therefore, this cell-based NPA model can be used for further study of disease pathophysiology and for high-throughput screening of compound libraries to identify lead compounds for drug development. ©AlphaMed Press.

  2. Monitoring the effect of mechanical stress on mesenchymal stem cell collagen production by multiphoton microscopy

    NASA Astrophysics Data System (ADS)

    Chen, Wei-Liang; Chang, Chia-Cheng; Chiou, Ling-Ling; Li, Tsung-Hsien; Liu, Yuan; Lee, Hsuan-Shu; Dong, Chen-Yuan

    2008-02-01

    Tissue engineering is emerging as a promising method for repairing damaged tissues. Due to cartilage's common wear and injury, in vitro production of cartilage replacements have been an active area of research. Finding the optimal condition for the generation of the collagen matrix is crucial in reproducing cartilages that closely match those found in human. Using multiphoton autofluorescence and second-harmonic generation (SHG) microscopy we monitored the effect of mechanical stress on mesenchymal stem cell collagen production. Bone marrow mesenchymal stem cells in the form of pellets were cultured and periodically placed under different mechanical stress by centrifugation over a period of four weeks. The differently stressed samples were imaged several times during the four week period, and the collagen production under different mechanical stress is characterized.

  3. Induction of sensory neurons from neuroepithelial stem cells by the ISX9 small molecule

    PubMed Central

    Ali, Rouknuddin Qasim; Blomberg, Evelina; Falk, Anna; Ährlund-Richter, Lars; Ulfendahl, Mats

    2016-01-01

    Hearing impairment most often involves loss of sensory hair cells and auditory neurons. As this loss is permanent in humans, a cell therapy approach has been suggested to replace damaged cells. It is thus of interest to generate lineage restricted progenitor cells appropriate for cell based therapies. Human long-term self-renewing neuroepithelial stem (lt-NES) cell lines exhibit in vitro a developmental potency to differentiate into CNS neural lineages, and importantly lack this potency in vivo, i.e do not form teratomas. Small-molecules-driven differentiation is today an established route obtain specific cell derivatives from stem cells. In this study, we have investigated the effects of three small molecules SB431542, ISX9 and Metformin to direct differentiation of lt-NES cells into sensory neurons. Exposure of lt-NES cells to Metformin or SB431542 did not induce any marked induction of markers for sensory neurons. However, a four days exposure to the ISX9 small molecule resulted in reduced expression of NeuroD1 mRNA as well as enhanced mRNA levels of GATA3, a marker and important player in auditory neuron specification and development. Subsequent culture in the presence of the neurotrophic factors BDNF and NT3 for another seven days yielded a further increase of mRNA expression for GATA3. This regimen resulted in a frequency of up to 25-30% of cells staining positive for Brn3a/Tuj1. We conclude that an approach with ISX9 small molecule induction of lt-NES cells into auditory like neurons may thus be an attractive route for obtaining safe cell replacement therapy of sensorineural hearing loss. PMID:27335699

  4. Changes in microRNA expression during differentiation of embryonic and induced pluripotent stem cells to definitive endoderm.

    PubMed

    Francis, Natalie; Moore, Melanie; Asan, Simona G; Rutter, Guy A; Burns, Chris

    2015-01-01

    Pluripotent stem cells, including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), have the potential to treat type 1 diabetes through cell replacement therapy. However, the protocols used to generate insulin-expressing cells in vitro frequently result in cells which have an immature phenotype and are functionally restricted. MicroRNAs (miRNAs) are now known to be important in cell fate specification, and a unique miRNA signature characterises pancreatic development at the definitive endoderm stage. Several studies have described differences in miRNA expression between ESCs and iPSCs. Here we have used microarray analysis both to identify miRNAs up- or down-regulated upon endoderm formation, and also miRNAs differentially expressed between ESCs and iPSCs. Several miRNAs fulfilling both these criteria were identified, suggesting that differences in the expression of these miRNAs may affect the ability of pluripotent stem cells to differentiate into definitive endoderm. The expression of these miRNAs was validated by qRT-PCR, and the relationship between one of these miRNAs, miR-151a-5p, and its predicted target gene, SOX17, was investigated by luciferase assay, and suggested an interaction between miR-151a-5p and this key transcription factor. In conclusion, these findings demonstrate a unique miRNA expression pattern for definitive endoderm derived from both embryonic and induced pluripotent stem cells. Copyright © 2015 Elsevier B.V. All rights reserved.

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

    PubMed

    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.

  6. Future dentistry: cell therapy meets tooth and periodontal repair and regeneration

    PubMed Central

    Catón, Javier; Bostanci, Nagihan; Remboutsika, Eumorphia; De Bari, Cosimo; Mitsiadis, Thimios A

    2011-01-01

    Abstract Cell-based tissue repair of the tooth and – tooth-supporting – periodontal ligament (PDL) is a new attractive approach that complements traditional restorative or surgical techniques for replacement of injured or pathologically damaged tissues. In such therapeutic approaches, stem cells and/or progenitor cells are manipulated in vitro and administered to patients as living and dynamic biological agents. In this review, we discuss the clonogenic potential of human dental and periodontal tissues such as the dental pulp and the PDL and their potential for tooth and periodontal repair and/or regeneration. We propose novel therapeutic approaches using stem cells or progenitor cells, which are targeted to regenerate the lost dental or periodontal tissue. PMID:21199329

  7. Subretinally transplanted embryonic stem cells rescue photoreceptor cells from degeneration in the RCS rats.

    PubMed

    Schraermeyer, U; Thumann, G; Luther, T; Kociok, N; Armhold, S; Kruttwig, K; Andressen, C; Addicks, K; Bartz-Schmidt, K U

    2001-01-01

    The Royal College of Surgeons (RCS) rat is an animal model for retinal degeneration such as the age-related macular degeneration. The RCS rat undergoes a progressive retinal degeneration during the early postnatal period. A potential treatment to prevent this retinal degeneration is the transplantation into the subretinal space of cells that would replace functions of the degenerating retinal pigment epithelium (RPE) cells or may form neurotrophic factors. In this study we have investigated the potential of subretinally transplanted embryonic stem cells to prevent the genetically determined photoreceptor cell degeneration in the RCS rat. Embryonic stem cells from the inner cell mass of the mouse blastocyst were allowed to differentiate to neural precursor cells in vitro and were then transplanted into the subretinal space of 20-day-old RCS rats. Transplanted and sham-operated rats were sacrificed 2 months following cell transplantation. The eyes were enucleated and photoreceptor degeneration was quantified by analyzing and determining the thickness of the outer nuclear layer by light and electron microscopy. In the eyes transplanted with embryonic cells up to 8 rows of photoreceptor cell nuclei were observed, whereas in nontreated control eyes the outer nuclear layer had degenerated completely. Transplantation of embryonic stem cells appears to delay photoreceptor cell degeneration in RCS rats.

  8. Advances in repairing the degenerate retina by rod photoreceptor transplantation☆

    PubMed Central

    Pearson, Rachael A.

    2014-01-01

    Despite very different aetiologies, age-related macular degeneration (AMD) and most inherited retinal disorders culminate in the same final common pathway, loss of the light-sensitive photoreceptors. There are few clinical treatments and none can reverse the loss of vision. Photoreceptor replacement by transplantation is proposed as a broad treatment strategy applicable to all degenerations. The past decade has seen a number of landmark achievements in this field, which together provide strong justification for continuing investigation into photoreceptor replacement strategies. These include proof of principle for restoring vision by rod-photoreceptor transplantation in mice with congenital stationary night blindness and advances in stem cell biology, which have led to the generation of complete optic structures in vitro from embryonic stem cells. The latter represents enormous potential for generating suitable and renewable donor cells with which to achieve the former. However, there are still challenges presented by the degenerating recipient retinal environment that must be addressed as we move to translating these technologies towards clinical application. PMID:24412415

  9. Anxiety and the aging brain: stressed out over p53?

    PubMed

    Scrable, Heidi; Burns-Cusato, Melissa; Medrano, Silvia

    2009-12-01

    We propose a model in which cell loss in the aging brain is seen as a root cause of behavioral changes that compromise quality of life, including the onset of generalized anxiety disorder, in elderly individuals. According to this model, as stem cells in neurogenic regions of the adult brain lose regenerative capacity, worn-out, dead, or damaged neurons fail to be replaced, leaving gaps in function. As most replacement involves inhibitory interneurons, either directly or indirectly, the net result is the acquisition over time of a hyper-excitable state. The stress axis is subserved by all three neurogenic regions in the adult brain, making it particularly susceptible to these age-dependent changes. We outline a molecular mechanism by which hyper-excitation of the stress axis in turn activates the tumor suppressor p53. This reinforces the loss of stem cell proliferative capacity and interferes with the feedback mechanism by which the glucocorticoid receptor turns off neuroendocrine pathways and resets the axis.

  10. Proceedings: Regenerative Medicine for Lung Diseases: A CIRM Workshop Report.

    PubMed

    Kadyk, Lisa C; DeWitt, Natalie D; Gomperts, Brigitte

    2017-10-01

    The mission of the California Institute of Regenerative Medicine (CIRM) is to accelerate treatments to patients with unmet medical needs. In September 2016, CIRM sponsored a workshop held at the University of California, Los Angeles, to discuss regenerative medicine approaches for treatment of lung diseases and to identify the challenges remaining for advancing such treatments to the clinic and market approval. Workshop participants discussed current preclinical and clinical approaches to regenerative medicine in the lung, as well as the biology of lung stem cells and the role of stem cells in the etiology of various lung diseases. The outcome of this effort was the recognition that whereas transient cell delivery approaches are leading the way in the clinic, recent advances in the understanding of lung stem cell biology, in vitro and in vivo disease modeling, gene editing and replacement methods, and cell engraftment approaches raise the prospect of developing cures for some lung diseases in the foreseeable future. In addition, advances in in vitro modeling using lung organoids and "lung on a chip" technology are setting the stage for high quality small molecule drug screening to develop treatments for lung diseases with complex biology. Stem Cells Translational Medicine 2017;6:1823-1828. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  11. Employment of the Triple Helix concept for development of regenerative medicine applications based on human pluripotent stem cells

    PubMed Central

    2014-01-01

    Using human pluripotent stem cells as a source to generate differentiated progenies for regenerative medicine applications has attracted substantial interest during recent years. Having the capability to produce large quantities of human cells that can replace damaged tissue due to disease or injury opens novel avenues for relieving symptoms and also potentially offers cures for many severe human diseases. Although tremendous advancements have been made, there is still much research and development left before human pluripotent stem cell derived products can be made available for cell therapy applications. In order to speed up the development processes, we argue strongly in favor of cross-disciplinary collaborative efforts which have many advantages, especially in a relatively new field such as regenerative medicine based on human pluripotent stem cells. In this review, we aim to illustrate how some of the hurdles for bringing human pluripotent stem cell derivatives from bench-to-bed can be effectively addressed through the establishment of collaborative programs involving academic institutions, biotech industries, and pharmaceutical companies. By taking advantage of the strengths from each organization, innovation and productivity can be maximized from a resource perspective and thus, the chances of successfully bringing novel regenerative medicine treatment options to patients increase. PMID:24872863

  12. Induced Pluripotent Stem Cells in Huntington's Disease: Disease Modeling and the Potential for Cell-Based Therapy.

    PubMed

    Liu, Ling; Huang, Jin-Sha; Han, Chao; Zhang, Guo-Xin; Xu, Xiao-Yun; Shen, Yan; Li, Jie; Jiang, Hai-Yang; Lin, Zhi-Cheng; Xiong, Nian; Wang, Tao

    2016-12-01

    Huntington's disease (HD) is an incurable neurodegenerative disorder that is characterized by motor dysfunction, cognitive impairment, and behavioral abnormalities. It is an autosomal dominant disorder caused by a CAG repeat expansion in the huntingtin gene, resulting in progressive neuronal loss predominately in the striatum and cortex. Despite the discovery of the causative gene in 1993, the exact mechanisms underlying HD pathogenesis have yet to be elucidated. Treatments that slow or halt the disease process are currently unavailable. Recent advances in induced pluripotent stem cell (iPSC) technologies have transformed our ability to study disease in human neural cells. Here, we firstly review the progress made to model HD in vitro using patient-derived iPSCs, which reveal unique insights into illuminating molecular mechanisms and provide a novel human cell-based platform for drug discovery. We then highlight the promises and challenges for pluripotent stem cells that might be used as a therapeutic source for cell replacement therapy of the lost neurons in HD brains.

  13. Human induced pluripotent stem cells in Parkinson's disease: A novel cell source of cell therapy and disease modeling.

    PubMed

    Li, Wen; Chen, Shengdi; Li, Jia-Yi

    2015-11-01

    Human induced pluripotent stem cells (hiPSCs) and human embryonic stem cells (hESCs) are two novel cell sources for studying neurodegenerative diseases. Dopaminergic neurons derived from hiPSCs/hESCs have been implicated to be very useful in Parkinson's disease (PD) research, including cell replacement therapy, disease modeling and drug screening. Recently, great efforts have been made to improve the application of hiPSCs/hESCs in PD research. Considerable advances have been made in recent years, including advanced reprogramming strategies without the use of viruses or using fewer transcriptional factors, optimized methods for generating highly homogeneous neural progenitors with a larger proportion of mature dopaminergic neurons and better survival and integration after transplantation. Here we outline the progress that has been made in these aspects in recent years, particularly during the last year, and also discuss existing issues that need to be addressed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Differentiation and Characterization of Dopaminergic Neurons From Baboon Induced Pluripotent Stem Cells.

    PubMed

    Grow, Douglas A; Simmons, DeNard V; Gomez, Jorge A; Wanat, Matthew J; McCarrey, John R; Paladini, Carlos A; Navara, Christopher S

    2016-09-01

    : The progressive death of dopamine producing neurons in the substantia nigra pars compacta is the principal cause of symptoms of Parkinson's disease (PD). Stem cells have potential therapeutic use in replacing these cells and restoring function. To facilitate development of this approach, we sought to establish a preclinical model based on a large nonhuman primate for testing the efficacy and safety of stem cell-based transplantation. To this end, we differentiated baboon fibroblast-derived induced pluripotent stem cells (biPSCs) into dopaminergic neurons with the application of specific morphogens and growth factors. We confirmed that biPSC-derived dopaminergic neurons resemble those found in the human midbrain based on cell type-specific expression of dopamine markers TH and GIRK2. Using the reverse transcriptase quantitative polymerase chain reaction, we also showed that biPSC-derived dopaminergic neurons express PAX6, FOXA2, LMX1A, NURR1, and TH genes characteristic of this cell type in vivo. We used perforated patch-clamp electrophysiology to demonstrate that biPSC-derived dopaminergic neurons fired spontaneous rhythmic action potentials and high-frequency action potentials with spike frequency adaption upon injection of depolarizing current. Finally, we showed that biPSC-derived neurons released catecholamines in response to electrical stimulation. These results demonstrate the utility of the baboon model for testing and optimizing the efficacy and safety of stem cell-based therapeutic approaches for the treatment of PD. Functional dopamine neurons were produced from baboon induced pluripotent stem cells, and their properties were compared to baboon midbrain cells in vivo. The baboon has advantages as a clinically relevant model in which to optimize the efficacy and safety of stem cell-based therapies for neurodegenerative diseases, such as Parkinson's disease. Baboons possess crucial neuroanatomical and immunological similarities to humans, and baboon pluripotent stem cells can be differentiated into functional neurons that mimic those in the human brain, thus laying the foundation for the utility of the baboon model for evaluating stem cell therapies. ©AlphaMed Press.

  15. Conversion of partially reprogrammed cells to fully pluripotent stem cells is associated with further activation of stem cell maintenance- and gamete generation-related genes.

    PubMed

    Kim, Jong Soo; Choi, Hyun Woo; Choi, Sol; Seo, Han Geuk; Moon, Sung-Hwan; Chung, Hyung-Min; Do, Jeong Tae

    2014-11-01

    Somatic cells are reprogrammed to induced pluripotent stem cells (iPSCs) by overexpression of a combination of defined transcription factors. We generated iPSCs from mouse embryonic fibroblasts (with Oct4-GFP reporter) by transfection of pCX-OSK-2A (Oct4, Sox2, and Klf4) and pCX-cMyc vectors. We could generate partially reprogrammed cells (XiPS-7), which maintained more than 20 passages in a partially reprogrammed state; the cells expressed Nanog but were Oct4-GFP negative. When the cells were transferred to serum-free medium (with serum replacement and basic fibroblast growth factor), the XiPS-7 cells converted to Oct4-GFP-positive iPSCs (XiPS-7c, fully reprogrammed cells) with ESC-like properties. During the conversion of XiPS-7 to XiPS-7c, we found several clusters of slowly reprogrammed genes, which were activated at later stages of reprogramming. Our results suggest that partial reprogrammed cells can be induced to full reprogramming status by serum-free medium, in which stem cell maintenance- and gamete generation-related genes were upregulated. These long-term expandable partially reprogrammed cells can be used to verify the mechanism of reprogramming.

  16. Stem cell research: applicability in dentistry.

    PubMed

    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.

  17. Human blood and marrow side population stem cell and Stro-1 positive bone marrow stromal cell numbers decline with age, with an increase in quality of surviving stem cells: Correlation with cytokines

    PubMed Central

    Brusnahan, S.K.; McGuire, T.R.; Jackson, J.D.; Lane, J.T.; Garvin, K.L.; O’Kane, B.J.; Berger, A.M.; Tuljapurkar, S.R.; Kessinger, M.A.; Sharp, J.G.

    2010-01-01

    Hematological deficiencies increase with aging leading to anemias, reduced hematopoietic stress responses and myelodysplasias. This study tested the hypothesis that side population hematopoietic stem cells (SP-HSC) would decrease with aging, correlating with IGF-1 and IL-6 levels and increases in bone marrow fat. Marrow was obtained from the femoral head and trochanteric region of the femur at surgery for total hip replacement (N = 100). Whole trabecular marrow samples were ground in a sterile mortar and pestle and cellularity and fat content determined. Marrow and blood mononuclear cells were stained with Hoechst dye and the SP-HSC profiles acquired. Marrow stromal cells (MSC) were enumerated flow cytometrically employing the Stro-1 antibody, and clonally in the colony forming unit fibroblast (CFU-F) assay. Plasma levels of IGF-1 (ng/ml) and IL-6 (pg/ml) were measured by ELISA. SP-HSC in blood and bone marrow decreased with age but the quality of the surviving stem cells increased. MSC decreased non-significantly. IGF-1 levels (mean = 30.7, SEM = 2) decreased and IL-6 levels (mean = 4.4, SEM = 1) increased with age as did marrow fat (mean = 1.2 mm fat/g, SEM = 0.04). There were no significant correlations between cytokine levels or fat and SP-HSC numbers. Stem cells appear to be progressively lost with aging and only the highest quality stem cells survive. PMID:21035480

  18. Effect of culture medium on propagation and phenotype of corneal stroma-derived stem cells.

    PubMed

    Sidney, Laura E; Branch, Matthew J; Dua, Harminder S; Hopkinson, Andrew

    2015-12-01

    The limbal area of the corneal stroma has been identified as a source of mesenchymal-like stem cells, which have potential for exploitation as a cell therapy. However, the optimal culture conditions are disputed and few direct media comparisons have been performed. In this report, we evaluated several media types to identify the optimal for inducing an in vitro stem cell phenotype. Primary human corneal stroma-derived stem cells (CSSCs) were extracted from corneoscleral rims. Culture in seven different media types was compared: Dulbecco's modified Eagle's medium (DMEM) with 10% fetal bovine serum (FBS); M199 with 20% FBS; DMEM-F12 with 20% serum replacement, basic fibroblast growth factor and leukemia inhibitory factor (SCM); endothelial growth medium (EGM); semi-solid MethoCult; serum-free keratinocyte medium (K-SFM); and StemPro-34. Effects on proliferation, morphology, protein and messenger RNA expression were evaluated. All media supported proliferation of CSSCs with the exception of K-SFM and StemPro-34. Morphology differed between media: DMEM produced large cells, whereas EGM produced very small cells. Culture in M199 produced a typical mesenchymal stromal cell phenotype with high expression of CD105, CD90 and CD73 but not CD34. Culture in SCM produced a phenotype more reminiscent of a progenitor cell type with expression of CD34, ABCG2, SSEA-4 and PAX6. Culture medium can significantly influence CSSC phenotype. SCM produced a cell phenotype closest to that of a pluripotent stem cell, and we consider it to be the most appropriate for development as a clinical-grade medium for the production of CSSC phenotypes suitable for cell therapy. Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  19. Liver regenerative medicine: advances and challenges.

    PubMed

    Chistiakov, Dimitry A

    2012-01-01

    Liver transplantation is the standard care for many end-stage liver diseases. However, donor organs are scarce and some people succumb to liver failure before a donor is found. Liver regenerative medicine is a special interdisciplinary field of medicine focused on the development of new therapies incorporating stem cells, gene therapy and engineered tissues in order to repair or replace the damaged organ. In this review we consider the emerging progress achieved in the hepatic regenerative medicine within the last decade. The review starts with the characterization of liver organogenesis, fetal and adult stem/progenitor cells. Then, applications of primary hepatocytes, embryonic and adult (mesenchymal, hematopoietic and induced pluripotent) stem cells in cell therapy of liver diseases are considered. Current advances and challenges in producing mature hepatocytes from stem/progenitor cells are discussed. A section about hepatic tissue engineering includes consideration of synthetic and natural biomaterials in engineering scaffolds, strategies and achievements in the development of 3D bioactive matrices and 3D hepatocyte cultures, liver microengineering, generating bioartificial liver and prospects for fabrication of the bioengineered liver. Copyright © 2012 S. Karger AG, Basel.

  20. Human RPE Stem Cells Grown into Polarized RPE Monolayers on a Polyester Matrix Are Maintained after Grafting into Rabbit Subretinal Space

    PubMed Central

    Stanzel, Boris V.; Liu, Zengping; Somboonthanakij, Sudawadee; Wongsawad, Warapat; Brinken, Ralf; Eter, Nicole; Corneo, Barbara; Holz, Frank G.; Temple, Sally; Stern, Jeffrey H.; Blenkinsop, Timothy A.

    2014-01-01

    Summary Transplantation of the retinal pigment epithelium (RPE) is being developed as a cell-replacement therapy for age-related macular degeneration. Human embryonic stem cell (hESC) and induced pluripotent stem cell (iPSC)-derived RPE are currently translating toward clinic. We introduce the adult human RPE stem cell (hRPESC) as an alternative RPE source. Polarized monolayers of adult hRPESC-derived RPE grown on polyester (PET) membranes had near-native characteristics. Trephined pieces of RPE monolayers on PET were transplanted subretinally in the rabbit, a large-eyed animal model. After 4 days, retinal edema was observed above the implant, detected by spectral domain optical coherence tomography (SD-OCT) and fundoscopy. At 1 week, retinal atrophy overlying the fetal or adult transplant was observed, remaining stable thereafter. Histology obtained 4 weeks after implantation confirmed a continuous polarized human RPE monolayer on PET. Taken together, the xeno-RPE survived with retained characteristics in the subretinal space. These experiments support that adult hRPESC-derived RPE are a potential source for transplantation therapies. PMID:24511471

  1. Differentiation of neural crest stem cells from nasal mucosa into motor neuron-like cells.

    PubMed

    Bagher, Zohreh; Kamrava, Seyed Kamran; Alizadeh, Rafieh; Farhadi, Mohammad; Absalan, Moloud; Falah, Masoumeh; Faghihi, Faezeh; Zare-Sadeghi, Arash; Komeili, Ali

    2018-05-25

    Cell transplantation is a potential therapeutic approach for repairing neuropathological and neurodegenerative disorders of central nervous system by replacing the degenerated cells with new ones. Among a variety of stem cell candidates to provide these new cells, olfactory ectomesenchymal stem cells (OE-MSCs) have attracted a great attention due to their neural crest origin, easy harvest, high proliferation, and autologous transplantation. Since there is no report on differentiation potential of these cells into motor neuron-like cells, we evaluated this potential using Real-time PCR, flowcytometry and immunocytochemistry after the treatment with differentiation cocktail containing retinoic acid and Sonic Hedgehog. Immunocytochemistry staining of the isolated OE-MSCs demonstrated their capability to express nestin and vimentin, as the two markers of primitive neuroectoderm. The motor neuron differentiation of OE-MSCs resulted in changing their morphology into bipolar cells with high expression of motor neuron markers of ChAT, Hb-9 and Islet-1 at the level of mRNA and protein. Consequently, we believe that the OE-MSCs have great potential to differentiate into motor neuron-like cells and can be an ideal stem cell source for the treatment of motor neuron-related disorders of central nervous system. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Concise Review: Cell Surface N-Linked Glycoproteins as Potential Stem Cell Markers and Drug Targets.

    PubMed

    Boheler, Kenneth R; Gundry, Rebekah L

    2017-01-01

    Stem cells and their derivatives hold great promise to advance regenerative medicine. Critical to the progression of this field is the identification and utilization of antibody-accessible cell-surface proteins for immunophenotyping and cell sorting-techniques essential for assessment and isolation of defined cell populations with known functional and therapeutic properties. Beyond their utility for cell identification and selection, cell-surface proteins are also major targets for pharmacological intervention. Although comprehensive cell-surface protein maps are highly valuable, they have been difficult to define until recently. In this review, we discuss the application of a contemporary targeted chemoproteomic-based technique for defining the cell-surface proteomes of stem and progenitor cells. In applying this approach to pluripotent stem cells (PSCs), these studies have improved the biological understanding of these cells, led to the enhanced use and development of antibodies suitable for immunophenotyping and sorting, and contributed to the repurposing of existing drugs without the need for high-throughput screening. The utility of this latter approach was first demonstrated with human PSCs (hPSCs) through the identification of small molecules that are selectively toxic to hPSCs and have the potential for eliminating confounding and tumorigenic cells in hPSC-derived progeny destined for research and transplantation. Overall, the cutting-edge technologies reviewed here will accelerate the development of novel cell-surface protein targets for immunophenotyping, new reagents to improve the isolation of therapeutically qualified cells, and pharmacological studies to advance the treatment of intractable diseases amenable to cell-replacement therapies. Stem Cells Translational Medicine 2017;6:131-138. © 2016 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  3. Mesenchymal Cells of the Intestinal Lamina Propria

    PubMed Central

    Powell, D.W.; Pinchuk, I.V.; Saada, J.I.; Chen, Xin; Mifflin, R.C.

    2013-01-01

    The mesenchymal elements of the intestinal lamina propria reviewed here are the myofibroblasts, fibroblasts, mural cells (pericytes) of the vasculature, bone marrow–derived stromal stem cells, smooth muscle of the muscularis mucosae, and smooth muscle surrounding the lymphatic lacteals. These cells share similar marker molecules, origins, and coordinated biological functions previously ascribed solely to subepithelial myofibroblasts. We review the functional anatomy of intestinal mesenchymal cells and describe what is known about their origin in the embryo and their replacement in adults. As part of their putative role in intestinal mucosal morphogenesis, we consider the intestinal stem cell niche. Lastly, we review emerging information about myofibroblasts as nonprofessional immune cells that may be important as an alarm system for the gut and as a participant in peripheral immune tolerance. PMID:21054163

  4. Translating G-CSF as an Adjunct Therapy to Stem Cell Transplantation for Stroke.

    PubMed

    Peña, Ike dela; Borlongan, Cesar V

    2015-12-01

    Among recently investigated stroke therapies, stem cell treatment holds great promise by virtue of their putative ability to replace lost cells, promote endogenous neurogenesis,and produce behavioral and functional improvement through their "bystander effects." Translating stem cell in the clinic, however, presents a number of technical difficulties. A strategy suggested to enhance therapeutic utility of stem cells is combination therapy, i.e., co-transplantation of stem cells or adjunct treatment with pharmacological agents and substrates,which is assumed to produce more profound therapeutic benefits by circumventing limitations of individual treatments and facilitating complementary brain repair processes. We previously demonstrated enhanced functional effects of cotreatment with granulocyte-colony stimulating factor (GCSF)and human umbilical cord blood cell (hUCB) transplantation in animal models of traumatic brain injury (TBI). Here,we suggest that the aforementioned combination therapy may also produce synergistic effects in stroke. Accordingly, G-CSF treatment may reduce expression of pro-inflammatory cytokines and enhance neurogenesis rendering a receptive microenvironment for hUCB engraftment. Adjunct treatment of GCSF with hUCB may facilitate stemness maintenance and guide neural lineage commitment of hUCB cells. Moreover, regenerative mechanisms afforded by G-CSF-mobilized endogenous stem cells, secretion of growth factors by hUCB grafts and G-CSF-recruited endothelial progenitor cells(EPCs), as well as the potential graft–host integration that may promote synaptic circuitry re-establishment could altogether produce more pronounced functional improvement in stroked rats subjected to a combination G-CSF treatment and hUCB transplantation. Nevertheless, differences in pathology and repair processes underlying TBI and stroke deserve consideration when testing the effects of combinatorial G-CSF and hUCB cell transplantation for stroke treatment. Further studies are also required to determine the safety and efficacy of this intervention in both preclinical and clinical stroke studies.

  5. Adipose-derived Stem Cells Stimulated with n-Butylidenephthalide Exhibit Therapeutic Effects in a Mouse Model of Parkinson's Disease.

    PubMed

    Chi, Kang; Fu, Ru-Huei; Huang, Yu-Chuen; Chen, Shih-Yin; Hsu, Ching-Ju; Lin, Shinn-Zong; Tu, Chi-Tang; Chang, Li-Hsun; Wu, Ping-An; Liu, Shih-Ping

    2018-03-01

    Parkinson's disease (PD) causes motor dysfunction and dopaminergic cell death. Drug treatments can effectively reduce symptoms but often cause unwanted side effects. Stem cell therapies using cell replacement or indirect beneficial secretomes have recently emerged as potential therapeutic strategies. Although various types of stem cells have been proposed as possible candidates, adipose-derived stem cells (ADSCs) are easily obtainable, more abundant, less ethically disputed, and able to differentiate into multiple cell lineages. However, treatment of PD using adult stem cells is known to be less efficacious than neuron or embryonic stem cell transplantation. Therefore, improved therapies are urgently needed. n-Butylidenephthalide (BP), which is extracted from Angelica sinensis, has been shown to have anti-inflammatory and neuroprotective effects. Indeed, we previously demonstrated that BP treatment of ADSCs enhances the expression of neurogenesis and homing factors such as nuclear receptor related 1 protein, stromal-derived factor 1, and brain-derived neurotrophic factor. In the present study, we examined the ability of BP-pretreated ADSC transplantation to improve PD motor symptoms and protect dopamine neurons in a mouse model of PD. We evaluated the results using neuronal behavior tests such as beam walking, rotarod, and locomotor activity tests. ADSCs with or without BP pretreatment were transplanted into the striatum. Our findings demonstrated that ADSC transplantation improved motor abilities with varied efficacies and that BP stimulation improved the therapeutic effects of transplantation. Dopaminergic cell numbers returned to normal in ADSC-transplanted mice after 22 d. In summary, stimulating ADSCs with BP improved PD recovery efficiency. Thus, our results provide important new strategies to improve stem cell therapies for neurodegenerative diseases in future studies.

  6. The Holy Grail of Orthopedic Surgery: Mesenchymal Stem Cells—Their Current Uses and Potential Applications

    PubMed Central

    Berebichez-Fridman, Roberto; Gómez-García, Ricardo; Berebichez-Fastlicht, Enrique; Olivos-Meza, Anell; Granados, Julio; Velasquillo, Cristina

    2017-01-01

    Only select tissues and organs are able to spontaneously regenerate after disease or trauma, and this regenerative capacity diminishes over time. Human stem cell research explores therapeutic regenerative approaches to treat various conditions. Mesenchymal stem cells (MSCs) are derived from adult stem cells; they are multipotent and exert anti-inflammatory and immunomodulatory effects. They can differentiate into multiple cell types of the mesenchyme, for example, endothelial cells, osteoblasts, chondrocytes, fibroblasts, tenocytes, vascular smooth muscle cells, and sarcomere muscular cells. MSCs are easily obtained and can be cultivated and expanded in vitro; thus, they represent a promising and encouraging treatment approach in orthopedic surgery. Here, we review the application of MSCs to various orthopedic conditions, namely, orthopedic trauma; muscle injury; articular cartilage defects and osteoarthritis; meniscal injuries; bone disease; nerve, tendon, and ligament injuries; spinal cord injuries; intervertebral disc problems; pediatrics; and rotator cuff repair. The use of MSCs in orthopedics may transition the practice in the field from predominately surgical replacement and reconstruction to bioregeneration and prevention. However, additional research is necessary to explore the safety and effectiveness of MSC treatment in orthopedics, as well as applications in other medical specialties. PMID:28698718

  7. Regeneration of Articular Cartilage in Lizard Knee from Resident Stem/Progenitor Cells

    PubMed Central

    Alibardi, Lorenzo

    2015-01-01

    The epiphysis of femur and tibia in the lizard Podarcis muralis can extensively regenerate after injury. The process involves the articular cartilage and metaphyseal (growth) plate after damage. The secondary ossification center present between the articular cartilage and the growth plate is replaced by cartilaginous epiphyses after about one month of regeneration at high temperature. The present study analyzes the origin of the chondrogenic cells from putative stem cells located in the growing centers of the epiphyses. The study is carried out using immunocytochemistry for the detection of 5BrdU-labeled long retaining cells and for the localization of telomerase, an enzyme that indicates stemness. The observations show that putative stem cells retaining 5BrdU and positive for telomerase are present in the superficial articular cartilage and metaphyseal growth plate located in the epiphyses. This observation suggests that these areas represent stem cell niches lasting for most of the lifetime of lizards. In healthy long bones of adult lizards, the addition of new chondrocytes from the stem cells population in the articular cartilage and the metaphyseal growth plate likely allows for slow, continuous longitudinal growth. When the knee is injured in the adult lizard, new populations of chondrocytes actively producing chondroitin sulfate proteoglycan are derived from these stem cells to allow for the formation of completely new cartilaginous epiphyses, possibly anticipating the re-formation of secondary centers in later stages. The study suggests that in this lizard species, the regenerative ability of the epiphyses is a pre-adaptation to the regeneration of the articular cartilage. PMID:26340619

  8. Short-Term Grafting of Human Neural Stem Cells: Electrophysiological Properties and Motor Behavioral Amelioration in Experimental Parkinsons Disease.

    PubMed

    Martnez-Serrano, Alberto; Pereira, Marta P; Avaliani, Natalia; Nelke, Anna; Kokaia, Merab; Ramos-Moreno, Tania

    2016-12-13

    Cell replacement therapy in Parkinsons disease (PD) still lacks a study addressing the acquisition of electrophysiological properties of human grafted neural stem cells and their relation with the emergence of behavioral recovery after transplantation in the short term. Here we study the electrophysiological and biochemical profiles of two ventral mesencephalic human neural stem cell (NSC) clonal lines (C30-Bcl-XL and C32-Bcl-XL) that express high levels of Bcl-XL to enhance their neurogenic capacity, after grafting in an in vitro parkinsonian model. Electrophysiological recordings show that the majority of the cells derived from the transplants are not mature at 6 weeks after grafting, but 6.7% of the studied cells showed mature electrophysiological profiles. Nevertheless, parallel in vivo behavioral studies showed a significant motor improvement at 7 weeks postgrafting in the animals receiving C30-Bcl-XL, the cell line producing the highest amount of TH+ cells. Present results show that, at this postgrafting time point, behavioral amelioration highly correlates with the spatial dispersion of the TH+ grafted cells in the caudate putamen. The spatial dispersion, along with a high number of dopaminergic-derived cells, is crucial for behavioral improvements. Our findings have implications for long-term standardization of stem cell-based approaches in Parkinsons disease.

  9. Reprogramming fibroblasts into induced pluripotent stem cells with Bmi1

    PubMed Central

    Moon, Jai-Hee; Heo, June Seok; Kim, Jun Sung; Jun, Eun Kyoung; Lee, Jung Han; Kim, Aeree; Kim, Jonggun; Whang, Kwang Youn; Kang, Yong-Kook; Yeo, Seungeun; Lim, Hee-Joung; Han, Dong Wook; Kim, Dong-Wook; Oh, Sejong; Yoon, Byung Sun; Schöler, Hans R; You, Seungkwon

    2011-01-01

    Somatic cells can be reprogrammed into induced pluripotent stem (iPS) cells by the transcription factors Oct4, Sox2, and Klf4 in combination with c-Myc. Recently, Sox2 plus Oct4 was shown to reprogram fibroblasts and Oct4 alone was able to reprogram mouse and human neural stem cells (NSCs) into iPS cells. Here, we report that Bmi1 leads to the transdifferentiation of mouse fibroblasts into NSC-like cells, and, in combination with Oct4, can replace Sox2, Klf4 and c-Myc during the reprogramming of fibroblasts into iPS cells. Furthermore, activation of sonic hedgehog signaling (by Shh, purmorphamine, or oxysterol) compensates for the effects of Bmi1, and, in combination with Oct4, reprograms mouse embryonic and adult fibroblasts into iPS cells. One- and two-factor iPS cells are similar to mouse embryonic stem cells in their global gene expression profile, epigenetic status, and in vitro and in vivo differentiation into all three germ layers, as well as teratoma formation and germline transmission in vivo. These data support that converting fibroblasts with Bmi1 or activation of the sonic hedgehog pathway to an intermediate cell type that expresses Sox2, Klf4, and N-Myc allows iPS generation via the addition of Oct4. PMID:21709693

  10. Chemical genetics and its potential in cardiac stem cell therapy

    PubMed Central

    Vieira, Joaquim M; Riley, Paul R

    2013-01-01

    Over the last decade or so, intensive research in cardiac stem cell biology has led to significant discoveries towards a potential therapy for cardiovascular disease; the main cause of morbidity and mortality in humans. The major goal within the field of cardiovascular regenerative medicine is to replace lost or damaged cardiac muscle and coronaries following ischaemic disease. At present, de novo cardiomyocytes can be generated either in vitro, for cell transplantation or disease modelling using directed differentiation of embryonic stem cells or induced pluripotent stem cells, or in vivo via direct reprogramming of resident adult cardiac fibroblast or ectopic stimulation of resident cardiac stem or progenitor cells. A major bottleneck with all of these approaches is the low efficiency of cardiomyocyte differentiation alongside their relative functional immaturity. Chemical genetics, and the application of phenotypic screening with small molecule libraries, represent a means to enhance understanding of the molecular pathways controlling cardiovascular cell differentiation and, moreover, offer the potential for discovery of new drugs to invoke heart repair and regeneration. Here, we review the potential of chemical genetics in cardiac stem cell therapy, highlighting not only the major contributions to the field so far, but also the future challenges. LINKED ARTICLES This article is part of a themed section on Regenerative Medicine and Pharmacology: A Look to the Future. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.169.issue-2 PMID:22385148

  11. Hydrogel-based scaffolds to support intrathecal stem cell transplantation as a gateway to the spinal cord: clinical needs, biomaterials, and imaging technologies.

    PubMed

    Oliveira, J Miguel; Carvalho, Luisa; Silva-Correia, Joana; Vieira, Sílvia; Majchrzak, Malgorzata; Lukomska, Barbara; Stanaszek, Luiza; Strymecka, Paulina; Malysz-Cymborska, Izabela; Golubczyk, Dominika; Kalkowski, Lukasz; Reis, Rui L; Janowski, Miroslaw; Walczak, Piotr

    2018-01-01

    The prospects for cell replacement in spinal cord diseases are impeded by inefficient stem cell delivery. The deep location of the spinal cord and complex surgical access, as well as densely packed vital structures, question the feasibility of the widespread use of multiple spinal cord punctures to inject stem cells. Disorders characterized by disseminated pathology are particularly appealing for the distribution of cells globally throughout the spinal cord in a minimally invasive fashion. The intrathecal space, with access to a relatively large surface area along the spinal cord, is an attractive route for global stem cell delivery, and, indeed, is highly promising, but the success of this approach relies on the ability of cells (1) to survive in the cerebrospinal fluid (CSF), (2) to adhere to the spinal cord surface, and (3) to migrate, ultimately, into the parenchyma. Intrathecal infusion of cell suspension, however, has been insufficient and we postulate that embedding transplanted cells within hydrogel scaffolds will facilitate reaching these goals. In this review, we focus on practical considerations that render the intrathecal approach clinically viable, and then discuss the characteristics of various biomaterials that are suitable to serve as scaffolds. We also propose strategies to modulate the local microenvironment with nanoparticle carriers to improve the functionality of cellular grafts. Finally, we provide an overview of imaging modalities for in vivo monitoring and characterization of biomaterials and stem cells. This comprehensive review should serve as a guide for those planning preclinical and clinical studies on intrathecal stem cell transplantation.

  12. A Stem Cell-Seeded Nanofibrous Scaffold for Auditory Nerve Replacement

    DTIC Science & Technology

    2013-10-01

    the brightest GFP+ cells by flow cytometry and compared these with GFP- cells (Figure 1A-C). The transfected cells showed robust GFP expression even...al., 2011), but no normative data were provided on SGN loss by cochlear turn and, in contrast to our results, those authors reported no impact on...A) Flow cytometry analysis to identify GFP+ and GFP- cells. The large cluster of cells on the left represent the GFP- cells and exhibited similar

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

    PubMed

    Merzaban, Jasmeen S; Imitola, Jaime; Starossom, Sarah C; Zhu, Bing; Wang, Yue; Lee, Jack; Ali, Amal J; Olah, Marta; Abuelela, Ayman F; Khoury, Samia J; Sackstein, Robert

    2015-12-01

    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. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Impaired cellulose synthase guidance leads to stem torsion and twists phyllotactic patterns in Arabidopsis.

    PubMed

    Landrein, Benoît; Lathe, Rahul; Bringmann, Martin; Vouillot, Cyril; Ivakov, Alexander; Boudaoud, Arezki; Persson, Staffan; Hamant, Olivier

    2013-05-20

    The parallel alignment of stiff cellulose microfibrils in plant-cell walls mediates anisotropic growth. This is largely controlled by cortical microtubules, which drive the insertion and trajectory of the cellulose synthase (CESA) complex at the plasma membrane. The CESA interactive protein 1 (CSI1) acts as a physical linker between CESA and cortical microtubules. Here we show that the inflorescence stems of csi1 mutants exhibit subtle right-handed torsion. Because cellulose deposition is largely uncoupled from cortical microtubules in csi1, we hypothesize that strictly transverse deposition of microfibrils in the wild-type is replaced by a helical orientation of uniform handedness in the mutant and that the helical microfibril alignment generates torsion. Interestingly, both elastic and viscous models for an expanding cell predict that a net helical orientation of microfibrils gives rise to a torque. We indeed observed tilted microfibrils in csi1 cells, and the torsion was almost absent in a csi1 prc1 background with impaired cellulose synthesis. In addition, the stem torsion led to a novel bimodal and robust phyllotactic pattern in the csi1 mutant, illustrating how growth perturbations can replace one robust mathematical pattern with a different, equally robust pattern. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Heart regeneration.

    PubMed

    Breckwoldt, Kaja; Weinberger, Florian; Eschenhagen, Thomas

    2016-07-01

    Regenerating an injured heart holds great promise for millions of patients suffering from heart diseases. Since the human heart has very limited regenerative capacity, this is a challenging task. Numerous strategies aiming to improve heart function have been developed. In this review we focus on approaches intending to replace damaged heart muscle by new cardiomyocytes. Different strategies for the production of cardiomyocytes from human embryonic stem cells or human induced pluripotent stem cells, by direct reprogramming and induction of cardiomyocyte proliferation are discussed regarding their therapeutic potential and respective advantages and disadvantages. Furthermore, different methods for the transplantation of pluripotent stem cell-derived cardiomyocytes are described and their clinical perspectives are discussed. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Comparison of differentiation potential of male mouse adipose tissue and bone marrow derived-mesenchymal stem cells into germ cells

    PubMed Central

    Hosseinzadeh Shirzeily, Maryam; Pasbakhsh, Parichehr; Amidi, Fardin; Mehrannia, Kobra; Sobhani, Aligholi

    2013-01-01

    Background: Recent publications about differentiation of stem cells to germ cells have motivated researchers to make new approaches to infertility. In vitro production of germ cells improves understanding differentiation process of male and female germ cells. Due to the problem of using embryonic stem cells (ESC), it’s necessary the mentioned cells be replaced with some adult multi-potent stem cells in laboratories. Objective: The aim of this study was to obtain germ cells from appropriate source beyond ESC and compare differential potentials of adipocytes derived stem cells (ADMSCs) with bone marrow derived stem cells (BMMSCs). Materials and Methods: To find multi-potential entity, after providing purified ADMSCs and BMMSCs, differentiation to osteoblast and adipocyte was confirmed by using appropriate culture medium. To confirm mesenchymal lineage production superficial markers (expression of CD90 and CD44 and non-expression of CD45 and CD31) were investigated by flowcytometry. Then the cells were differentiated to germ cells in inductive medium containing retinoic acid for 7days. To evaluate germ cells characteristic markers [Dazl (Deleted in azoospermia-like), Mvh (Mouse vasa homolog gene), Stra8 (Stimulated by retinoic acid) and Scp3 (Synaptonemal complex protein 3)] flowcytometry, imunoflorescence and real time PCR were used. Results: Both types of cells were able to differentiate into osteoblast and adipocyte cells and presentation of stem cell superficial markers (CD90, CD44) and absence of endothelial and blood cell markers (CD31, CD45) were confirmative The flowcytometry, imunoflorescence and real time PCR results showed remarkable expression of germ cells characteristic markers (Mvh, Dazl, Stra8, and Scp3). Conclusion: It was found that although ADMSCs were attained easier and also cultured and differentiated rapidly, germ cell markers were expressed in BMMSCs significantly more than ADMSCs. This article extracted from M.Sc. thesis. (Maryam Hosseinzadeh Shirzeily) PMID:24639722

  17. BRAIN REGENERATION IN PHYSIOLOGY AND PATHOLOGY: THE IMMUNE SIGNATURE DRIVING THERAPEUTIC PLASTICITY OF NEURAL STEM CELLS

    PubMed Central

    Martino, Gianvito; Pluchino, Stefano; Bonfanti, Luca; Schwartz, Michal

    2013-01-01

    Regenerative processes occurring under physiological (maintenance) and pathological (reparative) conditions are a fundamental part of life and vary greatly among different species, individuals, and tissues. Physiological regeneration occurs naturally as a consequence of normal cell erosion, or as an inevitable outcome of any biological process aiming at the restoration of homeostasis. Reparative regeneration occurs as a consequence of tissue damage. Although the central nervous system (CNS) has been considered for years as a “perennial” tissue, it has recently become clear that both physiological and reparative regeneration occur also within the CNS to sustain tissue homeostasis and repair. Proliferation and differentiation of neural stem/progenitor cells (NPCs) residing within the healthy CNS, or surviving injury, are considered crucial in sustaining these processes. Thus a large number of experimental stem cell-based transplantation systems for CNS repair have recently been established. The results suggest that transplanted NPCs promote tissue repair not only via cell replacement but also through their local contribution to changes in the diseased tissue milieu. This review focuses on the remarkable plasticity of endogenous and exogenous (transplanted) NPCs in promoting repair. Special attention will be given to the cross-talk existing between NPCs and CNS-resident microglia as well as CNS-infiltrating immune cells from the circulation, as a crucial event sustaining NPC-mediated neuroprotection. Finally, we will propose the concept of the context-dependent potency of transplanted NPCs (therapeutic plasticity) to exert multiple therapeutic actions, such as cell replacement, neurotrophic support, and immunomodulation, in CNS repair. PMID:22013212

  18. Toward beta cell replacement for diabetes

    PubMed Central

    Johannesson, Bjarki; Sui, Lina; Freytes, Donald O; Creusot, Remi J; Egli, Dieter

    2015-01-01

    The discovery of insulin more than 90 years ago introduced a life-saving treatment for patients with type 1 diabetes, and since then, significant progress has been made in clinical care for all forms of diabetes. However, no method of insulin delivery matches the ability of the human pancreas to reliably and automatically maintain glucose levels within a tight range. Transplantation of human islets or of an intact pancreas can in principle cure diabetes, but this approach is generally reserved for cases with simultaneous transplantation of a kidney, where immunosuppression is already a requirement. Recent advances in cell reprogramming and beta cell differentiation now allow the generation of personalized stem cells, providing an unlimited source of beta cells for research and for developing autologous cell therapies. In this review, we will discuss the utility of stem cell-derived beta cells to investigate the mechanisms of beta cell failure in diabetes, and the challenges to develop beta cell replacement therapies. These challenges include appropriate quality controls of the cells being used, the ability to generate beta cell grafts of stable cellular composition, and in the case of type 1 diabetes, protecting implanted cells from autoimmune destruction without compromising other aspects of the immune system or the functionality of the graft. Such novel treatments will need to match or exceed the relative safety and efficacy of available care for diabetes. PMID:25733347

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

    PubMed Central

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

    2017-01-01

    Objective: 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. Data Sources: 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.” Study Selection: Original articles and critical reviews on the topics were selected. Results: 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. Conclusions: 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. PMID:28937044

  20. Economic 3D-printing approach for transplantation of human stem cell-derived β-like cells

    PubMed Central

    Song, Jiwon; Millman, Jeffrey R.

    2016-01-01

    Transplantation of human pluripotent stem cells (hPSC) differentiated into insulin-producing β cells is a regenerative medicine approach being investigated for diabetes cell replacement therapy. This report presents a multifaceted transplantation strategy that combines differentiation into stem cell-derived β (SC-β) cells with 3D printing. By modulating the parameters of a low-cost 3D printer, we created a macroporous device composed of polylactic acid (PLA) that houses SC-β cell clusters within a degradable fibrin gel. Using finite element modeling of cellular oxygen diffusion-consumption and an in vitro culture system that allows for culture of devices at physiological oxygen levels, we identified cluster sizes that avoid severe hypoxia within 3D-printed devices and developed a microwell-based technique for resizing clusters within this range. Upon transplantation into mice, SC-β cell-embedded 3D-printed devices function for 12 weeks, are retrievable, and maintain structural integrity. Here, we demonstrate a novel 3D-printing approach that advances the use of differentiated hPSC for regenerative medicine applications and serves as a platform for future transplantation strategies. PMID:27906687

  1. Economic 3D-printing approach for transplantation of human stem cell-derived β-like cells.

    PubMed

    Song, Jiwon; Millman, Jeffrey R

    2016-12-01

    Transplantation of human pluripotent stem cells (hPSC) differentiated into insulin-producing β cells is a regenerative medicine approach being investigated for diabetes cell replacement therapy. This report presents a multifaceted transplantation strategy that combines differentiation into stem cell-derived β (SC-β) cells with 3D printing. By modulating the parameters of a low-cost 3D printer, we created a macroporous device composed of polylactic acid (PLA) that houses SC-β cell clusters within a degradable fibrin gel. Using finite element modeling of cellular oxygen diffusion-consumption and an in vitro culture system that allows for culture of devices at physiological oxygen levels, we identified cluster sizes that avoid severe hypoxia within 3D-printed devices and developed a microwell-based technique for resizing clusters within this range. Upon transplantation into mice, SC-β cell-embedded 3D-printed devices function for 12 weeks, are retrievable, and maintain structural integrity. Here, we demonstrate a novel 3D-printing approach that advances the use of differentiated hPSC for regenerative medicine applications and serves as a platform for future transplantation strategies.

  2. CRISPR-Cas9-Based Genome Editing of Human Induced Pluripotent Stem Cells.

    PubMed

    Giacalone, Joseph C; Sharma, Tasneem P; Burnight, Erin R; Fingert, John F; Mullins, Robert F; Stone, Edwin M; Tucker, Budd A

    2018-02-28

    Human induced pluripotent stem cells (hiPSCs) are the ideal cell source for autologous cell replacement. However, for patients with Mendelian diseases, genetic correction of the original disease-causing mutation is likely required prior to cellular differentiation and transplantation. The emergence of the CRISPR-Cas9 system has revolutionized the field of genome editing. By introducing inexpensive reagents that are relatively straightforward to design and validate, it is now possible to correct genetic variants or insert desired sequences at any location within the genome. CRISPR-based genome editing of patient-specific iPSCs shows great promise for future autologous cell replacement therapies. One caveat, however, is that hiPSCs are notoriously difficult to transfect, and optimized experimental design considerations are often necessary. This unit describes design strategies and methods for efficient CRISPR-based genome editing of patient- specific iPSCs. Additionally, it details a flexible approach that utilizes positive selection to generate clones with a desired genomic modification, Cre-lox recombination to remove the integrated selection cassette, and negative selection to eliminate residual hiPSCs with intact selection cassettes. © 2018 by John Wiley & Sons, Inc. Copyright © 2018 John Wiley & Sons, Inc.

  3. [Establishment of human embryonic stem cell lines and their therapeutic application].

    PubMed

    Suemori, Hirofumi

    2004-03-01

    Embryonic stem (ES) cell lines are pluripotent stem cell lines that can be propagated indefinitely in culture, retaining their potency to differentiate into every type of cell and tissue in the body. ES cell lines were first established from mouse blastocysts, and have been used for research in developmental biology. ES cells have been proven to be very valuable in the genetic modification of the mouse, especially in producing knockout mice. Since establishment of human ES cell lines was reported, their use in cell replacement therapies has been enthusiastically expected. There have been reports of the differentiation of several useful cell types from human ES cell lines, and clinical use of functional tissues and cells from human ES cells is anticipated. In Japan, there have also been many demands for the use of human ES cells in basic and pre-clinical research. We obtained governmental permission to establish human ES cell lines in April 2002 and started research using donated frozen embryos in January 2003. We successfully established three ES cell line from three blastocysts. These cell lines will be distributed at cost to researchers who have governmental permission to use human ES cells.

  4. Stem cell research and transplantation: science leading ethics.

    PubMed

    Daar, A S; Bhatt, A; Court, E; Singer, P A

    2004-10-01

    One of the most exciting developments in the biological sciences in the past decade has been the discovery and characterization of human embryonic stem cells (ESCs). The interest to transplanters is the potential applications of stem cells in regenerative medicine (RM), which may involve tissue engineering, genetic engineering, and other techniques to repair, replace, or regenerate failing tissues and organs. There is little controversy surrounding human adult stem cells. However, human ESCs are surrounded by a number of ethical controversies, the extent of which is partly dependent on their source. Those derived from currently existing embryonic stem cell lines are less controversial than those derived from "excess" embryos from in vitro fertilization (IVF) clinics, while ESCs derived from IVF embryos specifically created for the purpose are not acceptable to many people arguing from religious and other moral perspectives. Somatic cell nuclear transfer, or therapeutic cloning, must be distinguished from reproductive cloning. It holds the most promise for regenerative medicine. ESCs can also be derived from gonadal ridges of aborted fetuses. The transplant community must strive to uphold societal values in its effort to find remedies for their ailing patients and address the perennial problem of organ shortage. Transplanters also have a responsibility to engage the public in their efforts to gain public understanding and support, and policy makers must take into account public opinion. Only in this way can we realize the great potential of stem cell research for organ transplantation.

  5. Human Urine-Derived Stem Cells: Potential for Cell-Based Therapy of Cartilage Defects

    PubMed Central

    Chen, Long; Li, Lang; Xing, Fei; Peng, Jing; Peng, Kun; Wang, Yuanzheng

    2018-01-01

    Stem cell therapy is considered an optimistic approach to replace current treatments for cartilage defects. Recently, human urine-derived stem cells (hUSCs), which are isolated from the urine, are studied as a promising candidate for many tissue engineering therapies due to their multipotency and sufficient proliferation activities. However, it has not yet been reported whether hUSCs can be employed in cartilage defects. In this study, we revealed that induced hUSCs expressed chondrogenic-related proteins, including aggrecan and collagen II, and their gene expression levels were upregulated in vitro. Moreover, we combined hUSCs with hyaluronic acid (HA) and injected hUSCs-HA into a rabbit knee joint with cartilage defect. Twelve weeks after the injection, the histologic analyses (HE, toluidine blue, and Masson trichrome staining), immunohistochemistry (aggrecan and collagen II), and histologic grade of the sample indicated that hUSCs-HA could stimulate much more neocartilage formation compared with hUSCs alone, pure HA, and saline, which only induced the modest cartilage regeneration. In this study, we demonstrated that hUSCs could be a potential cell source for stem cell therapies to treat cartilage-related defects in the future. PMID:29765413

  6. Challenges of primate embryonic stem cell research.

    PubMed

    Bavister, Barry D; Wolf, Don P; Brenner, Carol A

    2005-01-01

    Embryonic stem (ES) cells hold great promise for treating degenerative diseases, including diabetes, Parkinson's, Alzheimer's, neural degeneration, and cardiomyopathies. This research is controversial to some because producing ES cells requires destroying embryos, which generally means human embryos. However, some of the surplus human embryos available from in vitro fertilization (IVF) clinics may have a high rate of genetic errors and therefore would be unsuitable for ES cell research. Although gross chromosome errors can readily be detected in ES cells, other anomalies such as mitochondrial DNA defects may have gone unrecognized. An insurmountable problem is that there are no human ES cells derived from in vivo-produced embryos to provide normal comparative data. In contrast, some monkey ES cell lines have been produced using in vivo-generated, normal embryos obtained from fertile animals; these can represent a "gold standard" for primate ES cells. In this review, we argue a need for strong research programs using rhesus monkey ES cells, conducted in parallel with studies on human ES and adult stem cells, to derive the maximum information about the biology of normal stem cells and to produce technical protocols for their directed differentiation into safe and functional replacement cells, tissues, and organs. In contrast, ES cell research using only human cell lines is likely to be incomplete, which could hinder research progress, and delay or diminish the effective application of ES cell technology to the treatment of human diseases.

  7. A method for deriving homogenous population of oligodendrocytes from mouse embryonic stem cells.

    PubMed

    Neman, J; de Vellis, J

    2012-06-01

    There is a pressing need for new therapeutics for the generation and transplantation of oligodendrocyte to the white matter to help replace and render injured cells that are lost in demyelinating disease. There are a few protocols describing a homogenous derivation of non-manipulated mouse embryonic stem cells to oligodendrocytes (ES-OL). Moreover, protocols that are successful in producing ES-OL do so with low efficiency. Therefore, we describe clear methodology for differentiation of mouse ES cells to oligodendrocyte to a high degree of homogenity and reproducibility in vitro. In addition, taking advantage of three defined media, we can generate a defined ES to oligodendrocyte lineage while selecting against neurons and astrocytes. More specifically, (1) Glial stem cell defining media (GSCDM), supplemented with appropriate combination of SHH and RA support pro-oligodendrocyte developing neural spheres from ES cells, (2) Oligodendrocyte differentiating media, induces lineage selection of oligodendrocytes progenitors from neural stem cells, and (3) Oligodendrocyte maturation media, supports oligodendrocytes progenitor maturation. Moreover, the ES cell derived oligodendrocytes display mature properites in the prescence of rat dorsal root gangila in vitro. Thus confirming thier potential for use to invesitgate developmental pathways and future potential use of cells in transplantation towards myelin repair. Copyright © 2012 Wiley Periodicals, Inc.

  8. Hydra as a tractable, long-lived model system for senescence.

    PubMed

    Bellantuono, Anthony J; Bridge, Diane; Martínez, Daniel E

    2015-01-30

    Hydra represents a unique model system for the study of senescence, with the opportunity for the comparison of non-aging and induced senescence. Hydra maintains three stem cell lineages, used for continuous tissue morphogenesis and replacement. Recent work has elucidated the roles of the insulin/IGF-1 signaling target FoxO, of Myc proteins, and of PIWI proteins in Hydra stem cells. Under laboratory culture conditions, Hydra vulgaris show no signs of aging even under long-term study. In contrast, Hydra oligactis can be experimentally induced to undergo reproduction-associated senescence. This provides a powerful comparative system for future studies.

  9. Daughters of the Enamel Organ: Development, Fate, and Function of the Stratum Intermedium, Stellate Reticulum, and Outer Enamel Epithelium

    PubMed Central

    Liu, Hui; Yan, Xiulin; Pandya, Mirali; Luan, Xianghong

    2016-01-01

    The tooth enamel organ (EO) is a complex epithelial cell assembly involved in multiple aspects of tooth development, including amelogenesis. The present study focuses on the role of the nonameloblast layers of the EO, the stratum intermedium, the stellate reticulum, and the outer enamel epithelium (OEE). The secretory stage stratum intermedium was distinguished by p63-positive epithelial stem cell marks, highly specific alkaline phosphatase labeling, as well as multiple desmosomes and gap junctions. At the location of the presecretory stage stellate reticulum, the pre-eruption EO prominently featured the papillary layer (PL) as a keratin immunopositive network of epithelial strands between tooth crowns and oral epithelium. PL cell strands contained numerous p63-positive epithelial stem cells, while BrdU proliferative cells were detected at the outer boundaries of the PL, suggesting that the stellate reticulum/PL epithelial cell sheath proliferated to facilitate an epithelial seal during tooth eruption. Comparative histology studies demonstrated continuity between the OEE and the general lamina of continuous tooth replacement in reptiles, and the outer layer of Hertwig's epithelial root sheath in humans, implicating the OEE as the formative layer for continuous tooth replacement and tooth root extension. Cell fate studies in organ culture verified that the cervical portion of the mouse molar EO gave rise to Malassez rest-like cell islands. Together, these studies indicate that the nonameloblast layers of the EO play multiple roles during odontogenesis, including the maintenance of several p63-positive stem cell reservoirs, a role during tooth root morphogenesis and tooth succession, a stabilizing function for the ameloblast layer, the facilitation of ion transport from the EO capillaries to the enamel layer, as well as safe and seamless tooth eruption. PMID:27611344

  10. Daughters of the Enamel Organ: Development, Fate, and Function of the Stratum Intermedium, Stellate Reticulum, and Outer Enamel Epithelium.

    PubMed

    Liu, Hui; Yan, Xiulin; Pandya, Mirali; Luan, Xianghong; Diekwisch, Thomas G H

    2016-09-09

    The tooth enamel organ (EO) is a complex epithelial cell assembly involved in multiple aspects of tooth development, including amelogenesis. The present study focuses on the role of the nonameloblast layers of the EO, the stratum intermedium, the stellate reticulum, and the outer enamel epithelium (OEE). The secretory stage stratum intermedium was distinguished by p63-positive epithelial stem cell marks, highly specific alkaline phosphatase labeling, as well as multiple desmosomes and gap junctions. At the location of the presecretory stage stellate reticulum, the pre-eruption EO prominently featured the papillary layer (PL) as a keratin immunopositive network of epithelial strands between tooth crowns and oral epithelium. PL cell strands contained numerous p63-positive epithelial stem cells, while BrdU proliferative cells were detected at the outer boundaries of the PL, suggesting that the stellate reticulum/PL epithelial cell sheath proliferated to facilitate an epithelial seal during tooth eruption. Comparative histology studies demonstrated continuity between the OEE and the general lamina of continuous tooth replacement in reptiles, and the outer layer of Hertwig's epithelial root sheath in humans, implicating the OEE as the formative layer for continuous tooth replacement and tooth root extension. Cell fate studies in organ culture verified that the cervical portion of the mouse molar EO gave rise to Malassez rest-like cell islands. Together, these studies indicate that the nonameloblast layers of the EO play multiple roles during odontogenesis, including the maintenance of several p63-positive stem cell reservoirs, a role during tooth root morphogenesis and tooth succession, a stabilizing function for the ameloblast layer, the facilitation of ion transport from the EO capillaries to the enamel layer, as well as safe and seamless tooth eruption.

  11. Robust G2 pausing of adult stem cells in Hydra.

    PubMed

    Buzgariu, Wanda; Crescenzi, Marco; Galliot, Brigitte

    2014-01-01

    Hydra is a freshwater hydrozoan polyp that constantly renews its two tissue layers thanks to three distinct stem cell populations that cannot replace each other, epithelial ectodermal, epithelial endodermal, and multipotent interstitial. These adult stem cells, located in the central body column, exhibit different cycling paces, slow for the epithelial, fast for the interstitial. To monitor the changes in cell cycling in Hydra, we established a fast and efficient flow cytometry procedure, which we validated by confirming previous findings, as the Nocodazole-induced reversible arrest of cell cycling in G2/M, and the mitogenic signal provided by feeding. Then to dissect the cycling and differentiation behaviors of the interstitial stem cells, we used the AEP_cnnos1 and AEP_Icy1 transgenic lines that constitutively express GFP in this lineage. For the epithelial lineages we used the sf-1 strain that rapidly eliminates the fast cycling cells upon heat-shock and progressively becomes epithelial. This study evidences similar cycling patterns for the interstitial and epithelial stem cells, which all alternate between the G2 and S-phases traversing a minimal G1-phase. We also found interstitial progenitors with a shorter G2 that pause in G1/G0. At the animal extremities, most cells no longer cycle, the epithelial cells terminally differentiate in G2 and the interstitial progenitors in G1/G0. At the apical pole ~80% cells are post-mitotic differentiated cells, reflecting the higher density of neurons and nematocytes in this region. We discuss how the robust G2 pausing of stem cells, maintained over weeks of starvation, may contribute to regeneration. Copyright © 2014 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  12. Using Polymer Confinement for Stem Cell Differentiation: 3D Printed vs Molded Scaffolds

    NASA Astrophysics Data System (ADS)

    Rafailovich, Miriam

    Additive manufacturing technologies are increasingly being used to replace standard extrusion or molding methods in engineering polymeric biomedical implants, which can be further seeded with cells for tissue regeneration. The principal advantage of this new technology is the ability to print directly from a scan and hence produce parts which are an ideal fit for an individual, eliminating much of the sizing and fitting associated with standard manufacturing methods. The question though arises whether devices which may be macroscopically similar, serve identical functions and are produced from the same material, interact in the same manner with cells and living tissue. Here we show that fundamental differences can exist between 3-D printed and extruded scaffolds which can impact stem cell differentiation and lineage selection. We will show how polymer confinement inherent in these methods affect the printed features on multiple length scales. We will also and how the differentiation of stem cells is affected by substrate heterogeneity in both morphological and mechanical features. NSF-Inspire award # 1344267.

  13. Stem Cells as a Tool to Improve Outcomes of Islet Transplantation

    PubMed Central

    Sims, Emily; Evans-Molina, Carmella

    2012-01-01

    The publication of the promising results of the Edmonton protocol in 2000 generated optimism for islet transplantation as a potential cure for Type 1 Diabetes Mellitus. Unfortunately, follow-up data revealed that less than 10% of patients achieved long-term insulin independence. More recent data from other large trials like the Collaborative Islet Transplant Registry show incremental improvement with 44% of islet transplant recipients maintaining insulin independence at three years of follow-up. Multiple underlying issues have been identified that contribute to islet graft failure, and newer research has attempted to address these problems. Stem cells have been utilized not only as a functional replacement for β cells, but also as companion or supportive cells to address a variety of different obstacles that prevent ideal graft viability and function. In this paper, we outline the manners in which stem cells have been applied to address barriers to the achievement of long-term insulin independence following islet transplantation. PMID:22970344

  14. Cardiogenic programming of human pluripotent stem cells by dose-controlled activation of EOMES.

    PubMed

    Pfeiffer, Martin J; Quaranta, Roberto; Piccini, Ilaria; Fell, Jakob; Rao, Jyoti; Röpke, Albrecht; Seebohm, Guiscard; Greber, Boris

    2018-01-30

    Master cell fate determinants are thought to induce specific cell lineages in gastrulation by orchestrating entire gene programs. The T-box transcription factor EOMES (eomesodermin) is crucially required for the development of the heart-yet it is equally important for endoderm specification suggesting that it may act in a context-dependent manner. Here, we define an unrecognized interplay between EOMES and the WNT signaling pathway in controlling cardiac induction by using loss and gain-of-function approaches in human embryonic stem cells. Dose-dependent EOMES induction alone can fully replace a cocktail of signaling molecules otherwise essential for the specification of cardiogenic mesoderm. Highly efficient cardiomyocyte programming by EOMES mechanistically involves autocrine activation of canonical WNT signaling via the WNT3 ligand, which necessitates a shutdown of this axis at a subsequent stage. Our findings provide insights into human germ layer induction and bear biotechnological potential for the robust production of cardiomyocytes from engineered stem cells.

  15. Human reaming debris: a source of multipotent stem cells.

    PubMed

    Wenisch, Sabine; Trinkaus, Katja; Hild, Anne; Hose, Dirk; Herde, Katja; Heiss, Christian; Kilian, Olaf; Alt, Volker; Schnettler, Reinhard

    2005-01-01

    The biological characteristics of human reaming debris (HRD) generated in the course of surgical treatment of long bone diaphyseal fractures and nonunions are still a matter of dispute. Therefore, the objective of the present investigation has been to characterize the intrinsic properties of human reaming debris in vitro. Samples of reaming debris harvested from 12 patients with closed diaphyseal fractures were examined ultrastucturally and were cultured under standard conditions. After a lag phase of 4-7 days, cells started to grow out from small bone fragments and established a confluent monolayer within 20-22 days. The cells were characterized according to morphology, proliferation capacity, cell surface antigen profile, and differentiation repertoire. The results reveal that human reaming debris is a source of multipotent stem cells which are able to grow and proliferate in vitro. The cells differentiate along the osteogenic pathway after induction and can be directed toward a neuronal phenotype, as has been shown morphologically and by the expression of neuronal markers after DMSO induction. These findings have prompted interest in the use of reaming debris-derived stem cells in cell and bone replacement therapies.

  16. Distal regeneration involves the age dependent activity of branchial sac stem cells in the ascidian Ciona intestinalis

    PubMed Central

    2014-01-01

    Abstract Tunicates have high capacities for regeneration but the underlying mechanisms and their relationship to life cycle progression are not well understood. Here we investigate the regeneration of distal structures in the ascidian tunicate Ciona intestinalis. Analysis of regenerative potential along the proximal−distal body axis indicated that distal organs, such as the siphons, their pigmented sensory organs, and the neural complex, could only be replaced from body fragments containing the branchial sac. Distal regeneration involves the formation of a blastema composed of cells that undergo cell proliferation prior to differentiation and cells that differentiate without cell proliferation. Both cell types originate in the branchial sac and appear in the blastema at different times after distal injury. Whereas the branchial sac stem cells are present in young animals, they are depleted in old animals that have lost their regeneration capacity. Thus Ciona adults contain a population of age‐related stem cells located in the branchial sac that are a source of precursors for distal body regeneration. PMID:25893097

  17. Human blood and marrow side population stem cell and Stro-1 positive bone marrow stromal cell numbers decline with age, with an increase in quality of surviving stem cells: correlation with cytokines.

    PubMed

    Brusnahan, S K; McGuire, T R; Jackson, J D; Lane, J T; Garvin, K L; O'Kane, B J; Berger, A M; Tuljapurkar, S R; Kessinger, M A; Sharp, J G

    2010-01-01

    Hematological deficiencies increase with aging leading to anemias, reduced hematopoietic stress responses and myelodysplasias. This study tested the hypothesis that side population hematopoietic stem cells (SP-HSC) would decrease with aging, correlating with IGF-1 and IL-6 levels and increases in bone marrow fat. Marrow was obtained from the femoral head and trochanteric region of the femur at surgery for total hip replacement (N=100). Whole trabecular marrow samples were ground in a sterile mortar and pestle and cellularity and fat content determined. Marrow and blood mononuclear cells were stained with Hoechst dye and the SP-HSC profiles acquired. Marrow stromal cells (MSC) were enumerated flow cytometrically employing the Stro-1 antibody, and clonally in the colony forming unit fibroblast (CFU-F) assay. Plasma levels of IGF-1 (ng/ml) and IL-6 (pg/ml) were measured by ELISA. SP-HSC in blood and bone marrow decreased with age but the quality of the surviving stem cells increased. MSC decreased non-significantly. IGF-1 levels (mean=30.7, SEM=2) decreased and IL-6 levels (mean=4.4, SEM=1) increased with age as did marrow fat (mean=1.2mmfat/g, SEM=0.04). There were no significant correlations between cytokine levels or fat and SP-HSC numbers. Stem cells appear to be progressively lost with aging and only the highest quality stem cells survive. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  18. Combining Induced Pluripotent Stem Cells and Genome Editing Technologies for Clinical Applications.

    PubMed

    Chang, Chia-Yu; Ting, Hsiao-Chien; Su, Hong-Lin; Jeng, Jing-Ren

    2018-01-01

    In this review, we introduce current developments in induced pluripotent stem cells (iPSCs), site-specific nuclease (SSN)-mediated genome editing tools, and the combined application of these two novel technologies in biomedical research and therapeutic trials. The sustainable pluripotent property of iPSCs in vitro not only provides unlimited cell sources for basic research but also benefits precision medicines for human diseases. In addition, rapidly evolving SSN tools efficiently tailor genetic manipulations for exploring gene functions and can be utilized to correct genetic defects of congenital diseases in the near future. Combining iPSC and SSN technologies will create new reliable human disease models with isogenic backgrounds in vitro and provide new solutions for cell replacement and precise therapies.

  19. Comparison of defined culture systems for feeder cell free propagation of human embryonic stem cells

    PubMed Central

    Akopian, Veronika; Beil, Stephen; Benvenisty, Nissim; Brehm, Jennifer; Christie, Megan; Ford, Angela; Fox, Victoria; Gokhale, Paul J.; Healy, Lyn; Holm, Frida; Hovatta, Outi; Knowles, Barbara B.; Ludwig, Tenneille E.; McKay, Ronald D. G.; Miyazaki, Takamichi; Nakatsuji, Norio; Oh, Steve K. W.; Pera, Martin F.; Rossant, Janet; Stacey, Glyn N.; Suemori, Hirofumi

    2010-01-01

    There are many reports of defined culture systems for the propagation of human embryonic stem cells in the absence of feeder cell support, but no previous study has undertaken a multi-laboratory comparison of these diverse methodologies. In this study, five separate laboratories, each with experience in human embryonic stem cell culture, used a panel of ten embryonic stem cell lines (including WA09 as an index cell line common to all laboratories) to assess eight cell culture methods, with propagation in the presence of Knockout Serum Replacer, FGF-2, and mouse embryonic fibroblast feeder cell layers serving as a positive control. The cultures were assessed for up to ten passages for attachment, death, and differentiated morphology by phase contrast microscopy, for growth by serial cell counts, and for maintenance of stem cell surface marker expression by flow cytometry. Of the eight culture systems, only the control and those based on two commercial media, mTeSR1 and STEMPRO, supported maintenance of most cell lines for ten passages. Cultures grown in the remaining media failed before this point due to lack of attachment, cell death, or overt cell differentiation. Possible explanations for relative success of the commercial formulations in this study, and the lack of success with other formulations from academic groups compared to previously published results, include: the complex combination of growth factors present in the commercial preparations; improved development, manufacture, and quality control in the commercial products; differences in epigenetic adaptation to culture in vitro between different ES cell lines grown in different laboratories. PMID:20186512

  20. Mesenchymal Stem Cells of Dental Origin for Inducing Tissue Regeneration in Periodontitis: A Mini-Review

    PubMed Central

    Hernández-Monjaraz, Beatriz; Santiago-Osorio, Edelmiro; Monroy-García, Alberto; Ledesma-Martínez, Edgar; Mendoza-Núñez, Víctor Manuel

    2018-01-01

    Periodontitis is a chronic disease that begins with a period of inflammation of the supporting tissues of the teeth table and then progresses, destroying the tissues until loss of the teeth occurs. The restoration of the damaged dental support apparatus is an extremely complex process due to the regeneration of the cementum, the periodontal ligament, and the alveolar bone. Conventional treatment relies on synthetic materials that fill defects and replace lost dental tissue, but these approaches are not substitutes for a real regeneration of tissue. To address this, there are several approaches to tissue engineering for regenerative dentistry, among them, the use of stem cells. Mesenchymal stem cells (MSC) can be obtained from various sources of adult tissues, such as bone marrow, adipose tissue, skin, and tissues of the orofacial area. MSC of dental origin, such as those found in the bone marrow, have immunosuppressive and immunotolerant properties, multipotency, high proliferation rates, and the capacity for tissue repair. However, they are poorly used as sources of tissue for therapeutic purposes. Their accessibility makes them an attractive source of mesenchymal stem cells, so this review describes the field of dental stem cell research and proposes a potential mechanism involved in periodontal tissue regeneration induced by dental MSC. PMID:29565801

  1. Stem cells and regenerative medicine: principles, prospects and problems.

    PubMed

    Gardner, Richard L

    2007-01-01

    Stem cells have been used routinely for more than three decades to repair tissues and organs damaged by injury or disease, most notably haematopoietic stem cells taken from bone marrow, umbilical cord or, increasingly, from peripheral blood. Other examples, such as grafts of skin to treat severe burns, entail transplantation of stem cells within organized tissue rather than following isolation. The prospect of exploiting stem cells more widely in regenerative medicine was encouraged both by the development of human assisted conception and growing evidence that various adult cells retained greater versatility than had been suspected hitherto. The aim is to employ stem cells as a source of appropriately differentiated cells to replace those lost through physical, chemical or ischaemic injury, or as a result of degenerative disease. This may entail transplantation of just a single type of cell or, more challengingly, require a complex of several different types of cells possessing a defined architecture. Cardiomyocytes, hepatocytes or neuronal cells producing specific transmitters offer promising examples of the former, although how transplanted healthy cells will function in a perturbed tissue environment remains to be established. Recent success in repairing urinary bladder defects with grafts of urothelial and muscle cells seeded on a biodegradable collagen scaffold is an encouraging step towards assembling organs in vitro. Nevertheless, this is still far removed from the level of sophistication required to counter the ever increasing shortfall in supply of kidneys for transplantation. Various problems must be addressed if recent advances in the laboratory are to be translated into clinical practice. In many cases, it has yet to be established that cells derived from adults that retain plasticity are actually stem cells. There is also a pressing need for appropriate assays to ensure that, regardless of source, stem cells maintained in vitro are safe to transplant. Assays currently available for human ES cells are far from ideal. It is, in addition, important to ensure that differentiated cultures are pure and, depending on whether cell renewal is required or to be avoided, retain or lack appropriate stem cells. Neither autografts nor those obtained by so-called 'therapeutic cloning' are options for treating condition with an obvious genetic basis. Moreover, claims that some stem cells are more likely than others to yield successful allografts have yet to be confirmed and explained.

  2. Cell renewal and apoptosis in macrostomum sp. [Lignano].

    PubMed

    Nimeth, K; Ladurner, P; Gschwentner, R; Salvenmoser, W; Rieger, R

    2002-01-01

    In platyhelminths, all cell renewal is accomplished by totipotent stem cells (neoblasts). Tissue maintenance is achieved in a balance between cell proliferation and apoptosis. It is known that in Macrostomum sp. the epidermis undergoes extensive cell renewal. Here we show that parenchymal cells also exhibit a high rate of cell turnover. We demonstrate cell renewal using continuous 5'bromo-2-deoxyuridine (BrdU) exposure. About one-third of all cells are replaced after 14 days. The high level of replacement requires an equivalent removal of cells by apoptosis. Cell death is characterized using a combination of three methods: (1). terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL), (2). specific binding of phosphatidyl-serine to fluorescent-labelled annexin V and (3). identification of apoptotic stages by ultrastructure. The number of cells observed in apoptosis is insufficient to explain the homeostasis of tissues in Macrostomum. Apoptosis-independent mechanisms may play an additional role in tissue dynamics.

  3. Dopaminergic differentiation of human mesenchymal stem cells--utilization of bioassay for tyrosine hydroxylase expression.

    PubMed

    Kan, Inna; Ben-Zur, Tali; Barhum, Yael; Levy, Yossef S; Burstein, Alex; Charlow, Tirza; Bulvik, Shlomo; Melamed, Eldad; Offen, Daniel

    2007-05-23

    Parkinson's disease (PD) is a neurodegenerative disorder, caused by a selective loss of dopaminergic neurons in the substantia nigra. In PD, the best therapeutic modalities cannot halt the degeneration. The selective hallmark pathology and the lack of effective treatment make PD an appropriate candidate for cell replacement therapy. Adult autologous bone-marrow-derived mesenchymal stem cells (MSCs) have been investigated as candidates for cell replacement strategies. Several laboratories, including ours, have induced MSCs into neuron-like cells demonstrating a variety of neuronal markers including dopaminergic characteristics, such as the expression of tyrosine hydroxylase (TH). This project aimed to induce MSCs into mature dopamine secreting cells and to generate a bioassay to evaluate the induction. For that purpose, we created a reporter vector containing a promoter of TH, the rate-limiting enzyme in the dopamine synthesis and red fluorescent protein DsRed2. Transfection of human neuroblastoma, dopamine synthesizing, SH-SY5Y cells confirmed the reliability of the constructed reporter plasmid. Following dopaminergic differentiation of the transfected human MSCs cells, TH expressing cells were identified and quantified using flow cytometry. Further study revealed that not only did the differentiated cells activate TH promoter but they also expressed TH protein and secreted dopamine. The reported results indicate that MSCs may be primed in vitro towards a dopaminergic fate offering the promise of innovative therapy for currently incurable human disorders, including PD.

  4. Human amniotic epithelial cells cultured in substitute serum medium maintain their stem cell characteristics for up to four passages.

    PubMed

    Evron, Ayelet; Goldman, Shlomit; Shalev, Eliezer

    2011-11-01

    The common applied culture medium in which human amniotic epithelial cells (hAECs) maintain their stem cell characteristics contains fetal calf serum (FCS) and thus is not compatible with possible future clinical applications due to the danger of animal derived pathogens. To overcome this problem, we replaced FCS with serum substitute supplement, a serum substitute used in the in vitro fertilization for embryo development, in the common applied culture medium and cultured hAECs in this substitute serum medium (SSM). Purity validation and characterization of freshly isolated and cultured hAECs was assessed through the expression of stem cell specific markers by RT-PCR (gene expression), by immunofluorescence staining and FACS (protein expression). Furthermore, karyotype was performed at passage four in order to exclude possible chromosome anomalies in hAECs cultured in SSM. The differentiation potential of hAECs into the cardiomyogenic lineage was tested through cardiac Troponin T expression by immunohistochemistry. hAECs cultured in SSM maintained expression of all the major pluripotent genes Sox-2, Oct-4 and Nanog as well as the expression of the embryonic stem cell specific surface antigens SSEA-4, SSEA-3 and TRA-1-60 over four passages. Using cardiac differentiation medium containing 10% serum substitute supplement, hAECs differentiated into cardiac troponin T expressing cells. We can conclude that, hAECs maintain their stem cell characteristics when cultured in SSM for up to 4 passages. This makes possible future clinical applications of these cells more feasible.

  5. A mex3 homolog is required for differentiation during planarian stem cell lineage development

    PubMed Central

    Zhu, Shu Jun; Hallows, Stephanie E; Currie, Ko W; Xu, ChangJiang; Pearson, Bret J

    2015-01-01

    Neoblasts are adult stem cells (ASCs) in planarians that sustain cell replacement during homeostasis and regeneration of any missing tissue. While numerous studies have examined genes underlying neoblast pluripotency, molecular pathways driving postmitotic fates remain poorly defined. In this study, we used transcriptional profiling of irradiation-sensitive and irradiation-insensitive cell populations and RNA interference (RNAi) functional screening to uncover markers and regulators of postmitotic progeny. We identified 32 new markers distinguishing two main epithelial progenitor populations and a planarian homolog to the MEX3 RNA-binding protein (Smed-mex3-1) as a key regulator of lineage progression. mex3-1 was required for generating differentiated cells of multiple lineages, while restricting the size of the stem cell compartment. We also demonstrated the utility of using mex3-1(RNAi) animals to identify additional progenitor markers. These results identified mex3-1 as a cell fate regulator, broadly required for differentiation, and suggest that mex3-1 helps to mediate the balance between ASC self-renewal and commitment. DOI: http://dx.doi.org/10.7554/eLife.07025.001 PMID:26114597

  6. Polymer-Based Reconstruction of the Inferior Vena Cava in Rat: Stem Cells or RGD Peptide?

    PubMed Central

    Pontailler, Margaux; Illangakoon, Eranka; Williams, Gareth R.; Marijon, Camille; Bellamy, Valérie; Balvay, Daniel; Autret, Gwenhael; Vanneaux, Valérie; Larghero, Jérôme; Planat-Benard, Valérie; Perier, Marie-Cécile; Bruneval, Patrick; Menasché, Philippe

    2015-01-01

    As part of a program targeted at developing a resorbable valved tube for replacement of the right ventricular outflow tract, we compared three biopolymers (polyurethane [PU], polyhydroxyalkanoate (the poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxyvalerate) [PHBVV]), and polydioxanone [PDO]) and two biofunctionalization techniques (using adipose-derived stem cells [ADSCs] or the arginine-glycine-aspartate [RGD] peptide) in a rat model of partial inferior vena cava (IVC) replacement. Fifty-three Wistar rats first underwent partial replacement of the IVC with an acellular electrospun PDO, PU, or PHBVV patch, and 31 nude rats subsequently underwent the same procedure using a PDO patch biofunctionalized either by ADSC or RGD. Results were assessed both in vitro (proliferation and survival of ADSC seeded onto the different materials) and in vivo by magnetic resonance imaging (MRI), histology, immunohistochemistry [against markers of vascular cells (von Willebrand factor [vWF], smooth muscle actin [SMA]), and macrophages ([ED1 and ED2] immunostaining)], and enzyme-linked immunosorbent assay (ELISA; for the expression of various cytokines and inducible NO synthase). PDO showed the best in vitro properties. Six weeks after implantation, MRI did not detect significant luminal changes in any group. All biopolymers were evenly lined by vWF-positive cells, but only PDO and PHBVV showed a continuous layer of SMA-positive cells at 3 months. PU patches resulted in a marked granulomatous inflammatory reaction. The ADSC and RGD biofunctionalization yielded similar outcomes. These data confirm the good biocompatibility of PDO and support the concept that appropriately peptide-functionalized polymers may be successfully substituted for cell-loaded materials. PMID:25611092

  7. Biocompatability of carbon nanotubes with stem cells to treat CNS injuries.

    PubMed

    Bokara, Kiran Kumar; Kim, Jong Youl; Lee, Young Il; Yun, Kyungeun; Webster, Tom J; Lee, Jong Eun

    2013-06-01

    Cases reporting traumatic injuries to the brain and spinal cord are extended range of disorders that affect a large percentage of the world's population. But, there are only few effective treatments available for central nervous system (CNS) injuries because the CNS is refractory to axonal regeneration and relatively inaccessible to many pharmacological treatments. The use of stem cell therapy in regenerative medicine has been extensively examined to replace lost cells during CNS injuries. But, given the complexity of CNS injuries oxidative stress, toxic byproducts, which prevails in the microenvironment during the diseased condition, may limit the survival of the transplanted stem cells affecting tissue regeneration and even longevity. Carbon nanotubes (CNT) are a new class of nanomaterials, which have been shown to be promising in different areas of nanomedicine for the prevention, diagnosis and therapy of certain diseases, including CNS diseases. In particular, the use of CNTs as substrates/scaffolds for supporting the stem cell differentiation has been an area of active research. Single-walled and multi-walled CNT's have been increasingly used as scaffolds for neuronal growth and more recently for neural stem cell growth and differentiation. This review summarizes recent research on the application of CNT-based materials to direct the differentiation of progenitor and stem cells toward specific neurons and to enhance axon regeneration and synaptogenesis for the effective treatment of CNS injuries. Nonetheless, accumulating data support the use of CNTs as a biocompatible and permissive substrate/scaffold for neural cells and such application holds great potential in neurological research.

  8. Biocompatability of carbon nanotubes with stem cells to treat CNS injuries

    PubMed Central

    Bokara, Kiran Kumar; Kim, Jong Youl; Lee, Young Il; Yun, Kyungeun; Webster, Tom J

    2013-01-01

    Cases reporting traumatic injuries to the brain and spinal cord are extended range of disorders that affect a large percentage of the world's population. But, there are only few effective treatments available for central nervous system (CNS) injuries because the CNS is refractory to axonal regeneration and relatively inaccessible to many pharmacological treatments. The use of stem cell therapy in regenerative medicine has been extensively examined to replace lost cells during CNS injuries. But, given the complexity of CNS injuries oxidative stress, toxic byproducts, which prevails in the microenvironment during the diseased condition, may limit the survival of the transplanted stem cells affecting tissue regeneration and even longevity. Carbon nanotubes (CNT) are a new class of nanomaterials, which have been shown to be promising in different areas of nanomedicine for the prevention, diagnosis and therapy of certain diseases, including CNS diseases. In particular, the use of CNTs as substrates/scaffolds for supporting the stem cell differentiation has been an area of active research. Single-walled and multi-walled CNT's have been increasingly used as scaffolds for neuronal growth and more recently for neural stem cell growth and differentiation. This review summarizes recent research on the application of CNT-based materials to direct the differentiation of progenitor and stem cells toward specific neurons and to enhance axon regeneration and synaptogenesis for the effective treatment of CNS injuries. Nonetheless, accumulating data support the use of CNTs as a biocompatible and permissive substrate/scaffold for neural cells and such application holds great potential in neurological research. PMID:23869255

  9. Repopulation of the fibrotic/cirrhotic rat liver by transplanted hepatic stem/progenitor cells and mature hepatocytes

    PubMed Central

    Yovchev, Mladen I.; Xue, Yuhua; Shafritz, David A.; Locker, Joseph; Oertel, Michael

    2013-01-01

    Background & Aim Considerable progress has been made in developing anti-fibrotic agents and other strategies to treat liver fibrosis; however, significant long-term restoration of functional liver mass has not yet been achieved. Therefore, we investigated whether transplanted hepatic stem/progenitor cells can effectively repopulate the liver with advanced fibrosis/cirrhosis. Methods Stem/progenitor cells derived from fetal livers or mature hepatocytes from DPPIV+ F344 rats were transplanted into DPPIV− rats with thioacetamide (TAA)-induced fibrosis/cirrhosis; rats were sacrificed 1, 2, or 4 months later. Liver tissues were analyzed by histochemistry, hydroxyproline determination, RT-PCR, and immunohistochemistry. Results After chronic TAA administration, DPPIV− F344 rats exhibited progressive fibrosis, cirrhosis and severe hepatocyte damage. Besides stellate cell activation, increased numbers of stem/progenitor cells (Dlk-1+, AFP+, CD133+, Sox-9+, FoxJ1+) were observed. In conjunction with partial hepatectomy (PH), transplanted stem/progenitor cells engrafted, proliferated competitively compared to host hepatocytes, differentiated into hepatocytic and biliary epithelial cells, and generated new liver mass with extensive long-term liver repopulation (40.8 ± 10.3%). Remarkably, more than 20% liver repopulation was achieved in the absence of PH, associated with reduced fibrogenic activity (e.g., expression of α-SMA, PDGFRβ, desmin, vimentin, TIMP1) and fibrosis (reduced collagen). Furthermore, hepatocytes can also replace liver mass with advanced fibrosis/cirrhosis, but to a lesser extent than FLSPCs. Conclusions This study is a Proof of Principle demonstration that transplanted epithelial stem/progenitor cells can restore injured parenchyma in a liver environment with advanced fibrosis/cirrhosis and exhibit anti-fibrotic effects. PMID:23840008

  10. Adult stem cell-based apexogenesis

    PubMed Central

    Li, Yao; Shu, Li-Hong; Yan, Ming; Dai, Wen-Yong; Li, Jun-Jun; Zhang, Guang-Dong; Yu, Jin-Hua

    2014-01-01

    Generally, the dental pulp needs to be removed when it is infected, and root canal therapy (RCT) is usually required in which infected dental pulp is replaced with inorganic materials (paste and gutta percha). This treatment approach ultimately brings about a dead tooth. However, pulp vitality is extremely important to the tooth itself, since it provides nutrition and acts as a biosensor to detect the potential pathogenic stimuli. Despite the reported clinical success rate, RCT-treated teeth are destined to be devitalized, brittle and susceptible to postoperative fracture. Recently, the advances and achievements in the field of stem cell biology and regenerative medicine have inspired novel biological approaches to apexogenesis in young patients suffering from pulpitis or periapical periodontitis. This review mainly focuses on the benchtop and clinical regeneration of root apex mediated by adult stem cells. Moreover, current strategies for infected pulp therapy are also discussed here. PMID:25332909

  11. Introduction of a point mutation into the mouse genome by homologous recombination in embryonic stem cells using a replacement type vector with a selectable marker.

    PubMed

    Rubinstein, M; Japón, M A; Low, M J

    1993-06-11

    The introduction of small mutations instead of null alleles into the mouse genome has broad applications to the study of protein structure-function relationships and the creation of animal models of human genetic diseases. To test a simple mutational strategy we designed a targeting vector for the mouse proopiomelanocortin (POMC) gene containing a single nucleotide insertion that converts the initial tyrosine codon of beta-endorphin 1-31 to a premature translational termination codon and introduces a unique Hpal endonuclease restriction site. The targeting vector also contains a neo cassette immediately 3' to the last POMC exon and a herpes simplex virus thymidine kinase cassette to allow positive and negative selection. Homologous recombination occurred at a frequency of 1/30 clones of electroporated embryonic stem cells selected in G418 and gancyclovir. 10/11 clones identified initially by a polymerase chain reaction (PCR) strategy had the predicted structure without evidence of concatemer formation by Southern blot analysis. We used a combination of Hpa I digestion of PCR amplified fragments and direct nucleotide sequencing to further confirm that the point mutation was retained in 9/10 clones. The POMC gene was transcriptionally silent in embryonic stem cells and the targeted allele was not activated by the downstream phosphoglycerate kinase-1 promoter that transcribed the neo gene. Under the electroporation conditions used, we have demonstrated that a point mutation can be introduced with high efficiency and precision into the POMC gene using a replacement type vector containing a retained selectable marker without affecting expression of the allele in the embryonic stem cells. A similar strategy may be useful for a wide range of genes.

  12. Introduction of a point mutation into the mouse genome by homologous recombination in embryonic stem cells using a replacement type vector with a selectable marker.

    PubMed Central

    Rubinstein, M; Japón, M A; Low, M J

    1993-01-01

    The introduction of small mutations instead of null alleles into the mouse genome has broad applications to the study of protein structure-function relationships and the creation of animal models of human genetic diseases. To test a simple mutational strategy we designed a targeting vector for the mouse proopiomelanocortin (POMC) gene containing a single nucleotide insertion that converts the initial tyrosine codon of beta-endorphin 1-31 to a premature translational termination codon and introduces a unique Hpal endonuclease restriction site. The targeting vector also contains a neo cassette immediately 3' to the last POMC exon and a herpes simplex virus thymidine kinase cassette to allow positive and negative selection. Homologous recombination occurred at a frequency of 1/30 clones of electroporated embryonic stem cells selected in G418 and gancyclovir. 10/11 clones identified initially by a polymerase chain reaction (PCR) strategy had the predicted structure without evidence of concatemer formation by Southern blot analysis. We used a combination of Hpa I digestion of PCR amplified fragments and direct nucleotide sequencing to further confirm that the point mutation was retained in 9/10 clones. The POMC gene was transcriptionally silent in embryonic stem cells and the targeted allele was not activated by the downstream phosphoglycerate kinase-1 promoter that transcribed the neo gene. Under the electroporation conditions used, we have demonstrated that a point mutation can be introduced with high efficiency and precision into the POMC gene using a replacement type vector containing a retained selectable marker without affecting expression of the allele in the embryonic stem cells. A similar strategy may be useful for a wide range of genes. Images PMID:8392702

  13. Advances in repairing the degenerate retina by rod photoreceptor transplantation.

    PubMed

    Pearson, Rachael A

    2014-01-01

    Despite very different aetiologies, age-related macular degeneration (AMD) and most inherited retinal disorders culminate in the same final common pathway, loss of the light-sensitive photoreceptors. There are few clinical treatments and none can reverse the loss of vision. Photoreceptor replacement by transplantation is proposed as a broad treatment strategy applicable to all degenerations. The past decade has seen a number of landmark achievements in this field, which together provide strong justification for continuing investigation into photoreceptor replacement strategies. These include proof of principle for restoring vision by rod-photoreceptor transplantation in mice with congenital stationary night blindness and advances in stem cell biology, which have led to the generation of complete optic structures in vitro from embryonic stem cells. The latter represents enormous potential for generating suitable and renewable donor cells with which to achieve the former. However, there are still challenges presented by the degenerating recipient retinal environment that must be addressed as we move to translating these technologies towards clinical application. Copyright © 2014 The Author. Published by Elsevier Inc. All rights reserved.

  14. A Stem Cell-Seeded Nanofibrous Scaffold for Auditory Nerve Replacement

    DTIC Science & Technology

    2015-10-01

    guinea pigs . Initial results show improved electrically-evoked auditory brainstem responses in cell-seeded implants compared to control, cell-free...scaffold’s conduit, but the IAM of the guinea pig and limits imposed by the surgical approach make this difficult. Alternatives are being pursued...transplantation of the seeded nanofibrous scaffold Task 13. Group 1: Pilot deafening. Confirm efficacy of ß-bungarotoxin in guinea pig and time point of

  15. The new generation of beta-cells: replication, stem cell differentiation, and the role of small molecules.

    PubMed

    Borowiak, Malgorzata

    2010-01-01

    Diabetic patients suffer from the loss of insulin-secreting β-cells, or from an improper working β-cell mass. Due to the increasing prevalence of diabetes across the world, there is a compelling need for a renewable source of cells that could replace pancreatic β-cells. In recent years, several promising approaches to the generation of new β-cells have been developed. These include directed differentiation of pluripotent cells such as embryonic stem (ES) cells or induced pluripotent stem (iPS) cells, or reprogramming of mature tissue cells. High yield methods to differentiate cell populations into β-cells, definitive endoderm, and pancreatic progenitors, have been established using growth factors and small molecules. However, the final step of directed differentiation to generate functional, mature β-cells in sufficient quantities has yet to be achieved in vitro. Beside the needs of transplantation medicine, a renewable source of β-cells would also be important in terms of a platform to study the pathogenesis of diabetes, and to seek alternative treatments. Finally, by generating new β-cells, we could learn more details about pancreatic development and β-cell specification. This review gives an overview of pancreas ontogenesis in the perspective of stem cell differentiation, and highlights the critical aspects of small molecules in the generation of a renewable β-cell source. Also, it discusses longer term challenges and opportunities in moving towards a therapeutic goal for diabetes.

  16. Cell Therapy Applications for Retinal Vascular Diseases: Diabetic Retinopathy and Retinal Vein Occlusion.

    PubMed

    Park, Susanna S

    2016-04-01

    Retinal vascular conditions, such as diabetic retinopathy and retinal vein occlusion, remain leading causes of vision loss. No therapy exists to restore vision loss resulting from retinal ischemia and associated retinal degeneration. Tissue regeneration is possible with cell therapy. The goal would be to restore or replace the damaged retinal vasculature and the retinal neurons that are damaged and/or degenerating from the hypoxic insult. Currently, various adult cell therapies have been explored as potential treatment. They include mesenchymal stem cells, vascular precursor cells (i.e., CD34+ cells, hematopoietic cells or endothelial progenitor cells), and adipose stromal cells. Preclinical studies show that all these cells have a paracrine trophic effect on damaged ischemic tissue, leading to tissue preservation. Endothelial progenitor cells and adipose stromal cells integrate into the damaged retinal vascular wall in preclinical models of diabetic retinopathy and ischemia-reperfusion injury. Mesenchymal stem cells do not integrate as readily but appear to have a primary paracrine trophic effect. Early phase clinical trials have been initiated and ongoing using mesenchymal stem cells or autologous bone marrow CD34+ cells injected intravitreally as potential therapy for diabetic retinopathy or retinal vein occlusion. Adipose stromal cells or pluripotent stem cells differentiated into endothelial colony-forming cells have been explored in preclinical studies and show promise as possible therapies for retinal vascular disorders. The relative safety or efficacy of these various cell therapies for treating retinal vascular disorders have yet to be determined.

  17. Novel methods of treating ovarian infertility in older and POF women, testicular infertility, and other human functional diseases.

    PubMed

    Bukovsky, Antonin

    2015-02-25

    In vitro maturation (IVM) and in vitro fertilization (IVF) technologies are facing with growing demands of older women to conceive. Although ovarian stem cells (OSCs) of older women are capable of producing in vitro fresh oocyte-like cells (OLCs), such cells cannot respond to IVM and IVF due to the lack of granulosa cells required for their maturation. Follicular renewal is also dependent on support of circulating blood mononuclear cells. They induce intermediary stages of meiosis (metaphase I chromosomal duplication and crossover, anaphase, telophase, and cytokinesis) in newly emerging ovarian germ cells, as for the first time demonstrated here, induce formation of granulosa cells, and stimulate follicular growth and development. A pretreatment of OSC culture with mononuclear cells collected from blood of a young healthy fertile woman may cause differentiation of bipotential OSCs into both developing germ and granulosa cells. A small blood volume replacement may enable treatment of ovarian infertility in vivo. The transferred mononuclear cells may temporarily rejuvenate virtually all tissues, including improvement of the function of endocrine tissues. Formation of new follicles and their development may be sufficient for IVM and IVF. The novel proposed in vitro approaches may be used as a second possibility. Infertility of human males affects almost a half of the infertility cases worldwide. Small blood volume replacement from young healthy fertile men may also be easy approach for the improvement of sperm quality in older or other affected men. In addition, body rejuvenation by small blood volume replacement from young healthy individuals of the same sex could represent a decline of in vitro methodology in favor of in vivo treatment for human functional diseases. Here we propose for the first time that blood mononuclear cells are essential for rejuvenation of those tissues, where immune system components participate in an appropriate division and differentiation of tissue stem cells. If needed, small blood volume replacement from distinct young healthy individuals could be utilized in six month intervals for repair of young altered or aged reproductive and other tissue functions. Systemic and local use of honey bee propolis tincture is an alternative option for functional rejuvenation of some tissues.

  18. Yin and Yang of mesenchymal stem cells and aplastic anemia

    PubMed Central

    Broglie, Larisa; Margolis, David; Medin, Jeffrey A

    2017-01-01

    Acquired aplastic anemia (AA) is a bone marrow failure syndrome characterized by peripheral cytopenias and bone marrow hypoplasia. It is ultimately fatal without treatment, most commonly from infection or hemorrhage. Current treatments focus on suppressing immune-mediated destruction of bone marrow stem cells or replacing hematopoietic stem cells (HSCs) by transplantation. Our incomplete understanding of the pathogenesis of AA has limited development of targeted treatment options. Mesenchymal stem cells (MSCs) play a vital role in HSC proliferation; they also modulate immune responses and maintain an environment supportive of hematopoiesis. Some of the observed clinical manifestations of AA can be explained by mesenchymal dysfunction. MSC infusions have been shown to be safe and may offer new approaches for the treatment of this disorder. Indeed, infusions of MSCs may help suppress auto-reactive, T-cell mediated HSC destruction and help restore an environment that supports hematopoiesis. Small pilot studies using MSCs as monotherapy or as adjuncts to HSC transplantation have been attempted as treatments for AA. Here we review the current understanding of the pathogenesis of AA and the function of MSCs, and suggest that MSCs should be a target for further research and clinical trials in this disorder. PMID:29321823

  19. Toward an animal model of cystic fibrosis: Targeted interruption of exon 10 of the cystic fibrosis transmembrane regulator gene in embryonic stem cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Koller, B.H.; Hyungsuk Kim; Latour, A.M.

    1991-12-01

    A gene-targeting construct was made containing 7.8 kilobases of DNA spanning exon 10 of the mouse cystic fibrosis transmembrane regulator (CFTR) gene in which part of the exon has been replaced by two neomycin-resistance (Neo) genes driven by different promoters. (This replacement introduces a chain-termination codon at amino acid position 489 in the CFTR sequence). A herpes simplex thymidine kinase gene was on each end of the construct, which was electroporated into embryonic stem (ES) cells. Colonies resistant to G418, or to G418 plus ganciclovir, were selected and screened by Southern blotting or by PCR amplification. Five pools of G418-resistantmore » cells gave PCR products diagnostic of targeting. Four independent clones of ES cells with a disrupted CFTR gene have been isolated from these pools. The frequency of targeting was 1/2500 G418-resistant colonies. This low frequency is not the consequence of marginal expression of the Neo genes in the targeted cells. The CFTR targeting events were clustered among our experiments in a manner suggesting that some unidentified factor(s), possible passage number, influences the recovery of CFTR-targeted cells.« less

  20. Stem Cells from Dental Pulp: What Epigenetics Can Do with Your Tooth

    PubMed Central

    Rodas-Junco, Beatriz A.; Canul-Chan, Michel; Rojas-Herrera, Rafael A.; De-la-Peña, Clelia; Nic-Can, Geovanny I.

    2017-01-01

    Adult stem cells have attracted scientific attention because they are able to self-renew and differentiate into several specialized cell types. In this context, human dental tissue-derived mesenchymal stem cells (hDT-MSCs) have emerged as a possible solution for repairing or regenerating damaged tissues. These cells can be isolated from primary teeth that are naturally replaced, third molars, or other dental tissues and exhibit self-renewal, a high proliferative rate and a great multilineage potential. However, the cellular and molecular mechanisms that determine lineage specification are still largely unknown. It is known that a change in cell fate requires the deletion of existing transcriptional programs, followed by the establishment of a new developmental program to give rise to a new cell lineage. Increasing evidence indicates that chromatin structure conformation can influence cell fate. In this way, reversible chemical modifications at the DNA or histone level, and combinations thereof can activate or inactivate cell-type-specific gene sequences, giving rise to an alternative cell fates. On the other hand, miRNAs are starting to emerge as a possible player in establishing particular somatic lineages. In this review, we discuss two new and promising research fields in medicine and biology, epigenetics and stem cells, by summarizing the properties of hDT-MSCs and highlighting the recent findings on epigenetic contributions to the regulation of cellular differentiation. PMID:29270128

  1. Tubular organ epithelialisation

    PubMed Central

    Saksena, Rhea; Gao, Chuanyu; Wicox, Mathew; de Mel, Achala

    2016-01-01

    Hollow, tubular organs including oesophagus, trachea, stomach, intestine, bladder and urethra may require repair or replacement due to disease. Current treatment is considered an unmet clinical need, and tissue engineering strategies aim to overcome these by fabricating synthetic constructs as tissue replacements. Smart, functionalised synthetic materials can act as a scaffold base of an organ and multiple cell types, including stem cells can be used to repopulate these scaffolds to replace or repair the damaged or diseased organs. Epithelial cells have not yet completely shown to have efficacious cell–scaffold interactions or good functionality in artificial organs, thus limiting the success of tissue-engineered grafts. Epithelial cells play an essential part of respective organs to maintain their function. Without successful epithelialisation, hollow organs are liable to stenosis, collapse, extensive fibrosis and infection that limit patency. It is clear that the source of cells and physicochemical properties of scaffolds determine the successful epithelialisation. This article presents a review of tissue engineering studies on oesophagus, trachea, stomach, small intestine, bladder and urethral constructs conducted to actualise epithelialised grafts. PMID:28228931

  2. Purification of Immature Neuronal Cells from Neural Stem Cell Progeny

    PubMed Central

    Azari, Hassan; Osborne, Geoffrey W.; Yasuda, Takahiro; Golmohammadi, Mohammad G.; Rahman, Maryam; Deleyrolle, Loic P.; Esfandiari, Ebrahim; Adams, David J.; Scheffler, Bjorn; Steindler, Dennis A.; Reynolds, Brent A.

    2011-01-01

    Large-scale proliferation and multi-lineage differentiation capabilities make neural stem cells (NSCs) a promising renewable source of cells for therapeutic applications. However, the practical application for neuronal cell replacement is limited by heterogeneity of NSC progeny, relatively low yield of neurons, predominance of astrocytes, poor survival of donor cells following transplantation and the potential for uncontrolled proliferation of precursor cells. To address these impediments, we have developed a method for the generation of highly enriched immature neurons from murine NSC progeny. Adaptation of the standard differentiation procedure in concert with flow cytometry selection, using scattered light and positive fluorescent light selection based on cell surface antibody binding, provided a near pure (97%) immature neuron population. Using the purified neurons, we screened a panel of growth factors and found that bone morphogenetic protein-4 (BMP-4) demonstrated a strong survival effect on the cells in vitro, and enhanced their functional maturity. This effect was maintained following transplantation into the adult mouse striatum where we observed a 2-fold increase in the survival of the implanted cells and a 3-fold increase in NeuN expression. Additionally, based on the neural-colony forming cell assay (N-CFCA), we noted a 64 fold reduction of the bona fide NSC frequency in neuronal cell population and that implanted donor cells showed no signs of excessive or uncontrolled proliferation. The ability to provide defined neural cell populations from renewable sources such as NSC may find application for cell replacement therapies in the central nervous system. PMID:21687800

  3. Stem cell therapies for age-related macular degeneration: the past, present, and future.

    PubMed

    Dang, Yalong; Zhang, Chun; Zhu, Yu

    2015-01-01

    In the developed world, age-related macular degeneration (AMD) is one of the major causes of irreversible blindness in the elderly. Although management of neovascular AMD (wet AMD) has dramatically progressed, there is still no effective treatment for nonneovascular AMD (dry AMD), which is characterized by retinal pigment epithelial (RPE) cell death (or dysfunction) and microenvironmental disruption in the retina. Therefore, RPE replacement and microenvironmental regulation represent viable treatments for dry AMD. Recent advances in cell biology have demonstrated that RPE cells can be easily generated from several cell types (pluripotent stem cells, multipotent stem cells, or even somatic cells) by spontaneous differentiation, coculturing, defined factors or cell reprogramming, respectively. Additionally, in vivo studies also showed that the restoration of visual function could be obtained by transplanting functional RPE cells into the subretinal space of recipient. More importantly, clinical trials approved by the US government have shown promising prospects in RPE transplantation. However, key issues such as implantation techniques, immune rejection, and xeno-free techniques are still needed to be further investigated. This review will summarize recent advances in cell transplantation for dry AMD. The obstacles and prospects in this field will also be discussed.

  4. Extracellular Vesicles from Bone Marrow‐Derived Mesenchymal Stem Cells Improve Survival from Lethal Hepatic Failure in Mice

    PubMed Central

    Haga, Hiroaki; Yan, Irene K.; Takahashi, Kenji; Matsuda, Akiko

    2017-01-01

    Abstract Stem cell‐based therapies have potential for treatment of liver injury by contributing to regenerative responses, through functional tissue replacement or paracrine effects. The release of extracellular vesicles (EV) from cells has been implicated in intercellular communication, and may contribute to beneficial paracrine effects of stem cell‐based therapies. Therapeutic effects of bone‐marrow derived mesenchymal stem cells (MSC) and vesicles released by these cells were examined in a lethal murine model of hepatic failure induced by d‐galactosamine/tumor necrosis factor‐α (TNF‐α). Systemically administered EV derived from MSC accumulated within the injured liver following systemic administration, reduced hepatic injury, and modulated cytokine expression. Moreover, survival was dramatically increased by EV derived from either murine or human MSC. Similar results were observed with the use of cryopreserved mMSC‐EV after 3 months. Y‐RNA‐1 was identified as a highly enriched noncoding RNA within hMSC‐EV compared to cells of origin. Moreover, siRNA mediated knockdown of Y‐RNA‐1 reduced the protective effects of MSC‐EV on TNF‐α/ActD‐mediated hepatocyte apoptosis in vitro. These data support a critical role for MSC‐derived EV in mediating reparative responses following hepatic injury, and provide compelling evidence to support the therapeutic use of MSC‐derived EV in fulminant hepatic failure. Stem Cells Translational Medicine 2017;6:1262–1272 PMID:28213967

  5. In vitro generation of three-dimensional substrate-adherent embryonic stem cell-derived neural aggregates for application in animal models of neurological disorders.

    PubMed

    Hargus, Gunnar; Cui, Yi-Fang; Dihné, Marcel; Bernreuther, Christian; Schachner, Melitta

    2012-05-01

    In vitro-differentiated embryonic stem (ES) cells comprise a useful source for cell replacement therapy, but the efficiency and safety of a translational approach are highly dependent on optimized protocols for directed differentiation of ES cells into the desired cell types in vitro. Furthermore, the transplantation of three-dimensional ES cell-derived structures instead of a single-cell suspension may improve graft survival and function by providing a beneficial microenvironment for implanted cells. To this end, we have developed a new method to efficiently differentiate mouse ES cells into neural aggregates that consist predominantly (>90%) of postmitotic neurons, neural progenitor cells, and radial glia-like cells. When transplanted into the excitotoxically lesioned striatum of adult mice, these substrate-adherent embryonic stem cell-derived neural aggregates (SENAs) showed significant advantages over transplanted single-cell suspensions of ES cell-derived neural cells, including improved survival of GABAergic neurons, increased cell migration, and significantly decreased risk of teratoma formation. Furthermore, SENAs mediated functional improvement after transplantation into animal models of Parkinson's disease and spinal cord injury. This unit describes in detail how SENAs are efficiently derived from mouse ES cells in vitro and how SENAs are isolated for transplantation. Furthermore, methods are presented for successful implantation of SENAs into animal models of Huntington's disease, Parkinson's disease, and spinal cord injury to study the effects of stem cell-derived neural aggregates in a disease context in vivo.

  6. Hypothalamic neurogenesis persists in the aging brain and is controlled by energy-sensing IGF-I pathway.

    PubMed

    Chaker, Zayna; George, Caroline; Petrovska, Marija; Caron, Jean-Baptiste; Lacube, Philippe; Caillé, Isabelle; Holzenberger, Martin

    2016-05-01

    Hypothalamic tanycytes are specialized glial cells lining the third ventricle. They are recently identified as adult stem and/or progenitor cells, able to self-renew and give rise to new neurons postnatally. However, the long-term neurogenic potential of tanycytes and the pathways regulating lifelong cell replacement in the adult hypothalamus are largely unexplored. Using inducible nestin-CreER(T2) for conditional mutagenesis, we performed lineage tracing of adult hypothalamic stem and/or progenitor cells (HySC) and demonstrated that new neurons continue to be born throughout adult life. This neurogenesis was targeted to numerous hypothalamic nuclei and produced different types of neurons in the dorsal periventricular regions. Some adult-born neurons integrated the median eminence and arcuate nucleus during aging and produced growth hormone releasing hormone. We showed that adult hypothalamic neurogenesis was tightly controlled by insulin-like growth factors (IGF). Knockout of IGF-1 receptor from hypothalamic stem and/or progenitor cells increased neuronal production and enhanced α-tanycyte self-renewal, preserving this stem cell-like population from age-related attrition. Our data indicate that adult hypothalamus retains the capacity of cell renewal, and thus, a substantial degree of structural plasticity throughout lifespan. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Knowledge Gaps in Rodent Pancreas Biology: Taking Human Pluripotent Stem Cell-Derived Pancreatic Beta Cells into Our Own Hands

    PubMed Central

    Santosa, Munirah Mohamad; Low, Blaise Su Jun; Pek, Nicole Min Qian; Teo, Adrian Kee Keong

    2016-01-01

    In the field of stem cell biology and diabetes, we and others seek to derive mature and functional human pancreatic β cells for disease modeling and cell replacement therapy. Traditionally, knowledge gathered from rodents is extended to human pancreas developmental biology research involving human pluripotent stem cells (hPSCs). While much has been learnt from rodent pancreas biology in the early steps toward Pdx1+ pancreatic progenitors, much less is known about the transition toward Ngn3+ pancreatic endocrine progenitors. Essentially, the later steps of pancreatic β cell development and maturation remain elusive to date. As a result, the most recent advances in the stem cell and diabetes field have relied upon combinatorial testing of numerous growth factors and chemical compounds in an arbitrary trial-and-error fashion to derive mature and functional human pancreatic β cells from hPSCs. Although this hit-or-miss approach appears to have made some headway in maturing human pancreatic β cells in vitro, its underlying biology is vaguely understood. Therefore, in this mini-review, we discuss some of these late-stage signaling pathways that are involved in human pancreatic β cell differentiation and highlight our current understanding of their relevance in rodent pancreas biology. Our efforts here unravel several novel signaling pathways that can be further studied to shed light on unexplored aspects of rodent pancreas biology. New investigations into these signaling pathways are expected to advance our knowledge in human pancreas developmental biology and to aid in the translation of stem cell biology in the context of diabetes treatments. PMID:26834702

  8. Knowledge Gaps in Rodent Pancreas Biology: Taking Human Pluripotent Stem Cell-Derived Pancreatic Beta Cells into Our Own Hands.

    PubMed

    Santosa, Munirah Mohamad; Low, Blaise Su Jun; Pek, Nicole Min Qian; Teo, Adrian Kee Keong

    2015-01-01

    In the field of stem cell biology and diabetes, we and others seek to derive mature and functional human pancreatic β cells for disease modeling and cell replacement therapy. Traditionally, knowledge gathered from rodents is extended to human pancreas developmental biology research involving human pluripotent stem cells (hPSCs). While much has been learnt from rodent pancreas biology in the early steps toward Pdx1(+) pancreatic progenitors, much less is known about the transition toward Ngn3(+) pancreatic endocrine progenitors. Essentially, the later steps of pancreatic β cell development and maturation remain elusive to date. As a result, the most recent advances in the stem cell and diabetes field have relied upon combinatorial testing of numerous growth factors and chemical compounds in an arbitrary trial-and-error fashion to derive mature and functional human pancreatic β cells from hPSCs. Although this hit-or-miss approach appears to have made some headway in maturing human pancreatic β cells in vitro, its underlying biology is vaguely understood. Therefore, in this mini-review, we discuss some of these late-stage signaling pathways that are involved in human pancreatic β cell differentiation and highlight our current understanding of their relevance in rodent pancreas biology. Our efforts here unravel several novel signaling pathways that can be further studied to shed light on unexplored aspects of rodent pancreas biology. New investigations into these signaling pathways are expected to advance our knowledge in human pancreas developmental biology and to aid in the translation of stem cell biology in the context of diabetes treatments.

  9. Using therapeutic cloning to fight human disease: a conundrum or reality?

    PubMed

    Hall, Vanessa J; Stojkovic, Petra; Stojkovic, Miodrag

    2006-07-01

    The development and transplantation of autologous cells derived from nuclear transfer embryonic stem cell (NT-ESC) lines to treat patients suffering from disease has been termed therapeutic cloning. Human NT is still a developing field, with further research required to improve somatic cell NT and human embryonic stem cell differentiation to deliver safe and effective cell replacement therapies. Furthermore, the implications of transferring mitochondrial heteroplasmic cells, which may harbor aberrant epigenetic gene expression profiles, are of concern. The production of human NT-ESC lines also remains plagued by ethical dilemmas, societal concerns, and controversies. Recently, a number of alternate therapeutic strategies have been proposed to circumvent the moral implications surrounding human nuclear transfer. It will be critical to overcome these biological, legislative, and moral restraints to maximize the potential of this therapeutic strategy and to alleviate human disease.

  10. Materials for stem cell factories of the future

    NASA Astrophysics Data System (ADS)

    Celiz, Adam D.; Smith, James G. W.; Langer, Robert; Anderson, Daniel G.; Winkler, David A.; Barrett, David A.; Davies, Martyn C.; Young, Lorraine E.; Denning, Chris; Alexander, Morgan R.

    2014-06-01

    Polymeric substrates are being identified that could permit translation of human pluripotent stem cells from laboratory-based research to industrial-scale biomedicine. Well-defined materials are required to allow cell banking and to provide the raw material for reproducible differentiation into lineages for large-scale drug-screening programs and clinical use. Yet more than 1 billion cells for each patient are needed to replace losses during heart attack, multiple sclerosis and diabetes. Producing this number of cells is challenging, and a rethink of the current predominant cell-derived substrates is needed to provide technology that can be scaled to meet the needs of millions of patients a year. In this Review, we consider the role of materials discovery, an emerging area of materials chemistry that is in large part driven by the challenges posed by biologists to materials scientists.

  11. Pancreatic Endoderm-Derived From Diabetic Patient-Specific Induced Pluripotent Stem Cell Generates Glucose-Responsive Insulin-Secreting Cells.

    PubMed

    Rajaei, Bahareh; Shamsara, Mehdi; Amirabad, Leila Mohammadi; Massumi, Mohammad; Sanati, Mohammad Hossein

    2017-10-01

    Human-induced pluripotent stem cells (hiPSCs) can potentially serve as an invaluable source for cell replacement therapy and allow the creation of patient- and disease-specific stem cells without the controversial use of embryos and avoids any immunological incompatibility. The generation of insulin-producing pancreatic β-cells from pluripotent stem cells in vitro provides an unprecedented cell source for personal drug discovery and cell transplantation therapy in diabetes. A new five-step protocol was introduced in this study, effectively induced hiPSCs to differentiate into glucose-responsive insulin-producing cells. This process mimics in vivo pancreatic organogenesis by directing cells through stages resembling definitive endoderm, primitive gut-tube endoderm, posterior foregut, pancreatic endoderm, and endocrine precursor. Each stage of differentiation were characterized by stage-specific markers. The produced cells exhibited many properties of functional β-cells, including expression of critical β-cells transcription factors, the potency to secrete C-peptide in response to high levels of glucose and the presence of mature endocrine secretory granules. This high efficient differentiation protocol, established in this study, yielded 79.18% insulin-secreting cells which were responsive to glucose five times higher than the basal level. These hiPSCs-derived glucose-responsive insulin-secreting cells might provide a promising approach for the treatment of type I diabetes mellitus. J. Cell. Physiol. 232: 2616-2625, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. Novel paths towards neural cellular products for neurological disorders.

    PubMed

    Daadi, Marcel M

    2011-11-01

    The prospect of using neural cells derived from stem cells or from reprogrammed adult somatic cells provides a unique opportunity in cell therapy and drug discovery for developing novel strategies for brain repair. Cell-based therapeutic approaches for treating CNS afflictions caused by disease or injury aim to promote structural repair of the injured or diseased neural tissue, an outcome currently not achieved by drug therapy. Preclinical research in animal models of various diseases or injuries report that grafts of neural cells enhance endogenous repair, provide neurotrophic support to neurons undergoing degeneration and replace lost neural cells. In recent years, the sources of neural cells for treating neurological disorders have been rapidly expanding and in addition to offering therapeutic potential, neural cell products hold promise for disease modeling and drug discovery use. Specific neural cell types have been derived from adult or fetal brain, from human embryonic stem cells, from induced pluripotent stem cells and directly transdifferentiated from adult somatic cells, such as skin cells. It is yet to be determined if the latter approach will evolve into a paradigm shift in the fields of stem cell research and regenerative medicine. These multiple sources of neural cells cover a wide spectrum of safety that needs to be balanced with efficacy to determine the viability of the cellular product. In this article, we will review novel sources of neural cells and discuss current obstacles to developing them into viable cellular products for treating neurological disorders.

  13. Niche recycling through division-independent egress of hematopoietic stem cells

    PubMed Central

    Czechowicz, Agnieszka; Ooi, A.G. Lisa; Rossi, Derrick J.; Bryder, David; Weissman, Irving L.

    2009-01-01

    Hematopoietic stem cells (HSCs) are thought to reside in discrete niches through stable adhesion, yet previous studies have suggested that host HSCs can be replaced by transplanted donor HSCs, even in the absence of cytoreductive conditioning. To explain this apparent paradox, we calculated, through cell surface phenotyping and transplantation of unfractionated blood, that ∼1–5% of the total pool of HSCs enters into the circulation each day. Bromodeoxyuridine (BrdU) feeding experiments demonstrated that HSCs in the peripheral blood incorporate BrdU at the same rate as do HSCs in the bone marrow, suggesting that egress from the bone marrow to the blood can occur without cell division and can leave behind vacant HSC niches. Consistent with this, repetitive daily transplantations of small numbers of HSCs administered as new niches became available over the course of 7 d led to significantly higher levels of engraftment than did large, single-bolus transplantations of the same total number of HSCs. These data provide insight as to how HSC replacement can occur despite the residence of endogenous HSCs in niches, and suggest therapeutic interventions that capitalize upon physiological HSC egress. PMID:19887396

  14. Stem Cell Research: A Novel Boulevard towards Improved Bovine Mastitis Management

    PubMed Central

    Sharma, Neelesh; Jeong, Dong Kee

    2013-01-01

    The dairy industry is a multi-billion dollar industry catering the nutritional needs of all age groups globally through the supply of milk. Clinical mastitis has a severe impact on udder tissue and is also an animal welfare issue. Moreover, it significantly reduces animal value and milk production. Mammary tissue damage reduces the number and activity of epithelial cells and consequently contributes to decreased milk production. The high incidence, low cure rate of this highly economic and sometimes deadly disease is an alarming for dairy sector as well as policy makers. Bovine mammary epithelial cells (MECs) and their stem cells are very important in milk production and bioengineering. The adult mammary epithelium consists of two main cell types; an inner layer of luminal epithelial cells, which produce the milk during lactation, and an outer layer of myoepithelial cells resting on a basement membrane, which are responsible for pushing the milk through the ductal network to the teat cistern. Inner layer of columner/luminal cells of bovine MECs, is characterized by cytokeratin18, 19 (CK18, CK19) and outer layer such as myoepithelial cells which are characterized by CK14, α-smooth muscle actin (α-SMA) and p63. Much work has been done in mouse and human, on mammary gland stem cell research, particularly in cancer therapy, but stem cell research in bovine is still in its infancy. Such stem/progenitor cell discoveries in human and mouse mammary gland bring some hope for application in bovines. These progenitors may be therapeutically adopted to correct the structural/cytological defects in the bovine udder due to mastitis. In the present review we focused on various kinds of stem/progenitor cells which can have therapeutic utility and their possibilities to use as a potential stem cell therapy in the management of bovine post-mastitis damage in orders to restore milk production. The possibilities of bovine mammary stem cell therapy offers significant potential for regeneration of tissues that can potentially replace/repair diseased and damaged tissue through differentiation into epithelial, myoepithelial and/or cuboidal/columnar cells in the udder with minimal risk of rejection and side effects. PMID:23983615

  15. Stem cell research: a novel boulevard towards improved bovine mastitis management.

    PubMed

    Sharma, Neelesh; Jeong, Dong Kee

    2013-01-01

    The dairy industry is a multi-billion dollar industry catering the nutritional needs of all age groups globally through the supply of milk. Clinical mastitis has a severe impact on udder tissue and is also an animal welfare issue. Moreover, it significantly reduces animal value and milk production. Mammary tissue damage reduces the number and activity of epithelial cells and consequently contributes to decreased milk production. The high incidence, low cure rate of this highly economic and sometimes deadly disease is an alarming for dairy sector as well as policy makers. Bovine mammary epithelial cells (MECs) and their stem cells are very important in milk production and bioengineering. The adult mammary epithelium consists of two main cell types; an inner layer of luminal epithelial cells, which produce the milk during lactation, and an outer layer of myoepithelial cells resting on a basement membrane, which are responsible for pushing the milk through the ductal network to the teat cistern. Inner layer of columner/luminal cells of bovine MECs, is characterized by cytokeratin18, 19 (CK18, CK19) and outer layer such as myoepithelial cells which are characterized by CK14, α-smooth muscle actin (α-SMA) and p63. Much work has been done in mouse and human, on mammary gland stem cell research, particularly in cancer therapy, but stem cell research in bovine is still in its infancy. Such stem/progenitor cell discoveries in human and mouse mammary gland bring some hope for application in bovines. These progenitors may be therapeutically adopted to correct the structural/cytological defects in the bovine udder due to mastitis. In the present review we focused on various kinds of stem/progenitor cells which can have therapeutic utility and their possibilities to use as a potential stem cell therapy in the management of bovine post-mastitis damage in orders to restore milk production. The possibilities of bovine mammary stem cell therapy offers significant potential for regeneration of tissues that can potentially replace/repair diseased and damaged tissue through differentiation into epithelial, myoepithelial and/or cuboidal/columnar cells in the udder with minimal risk of rejection and side effects.

  16. The current state of stem cell therapeutics: Canadian approaches in the international context.

    PubMed

    Noiseux, Nicolas; Marquis-Gravel, Guillaume; Mansour, Samer; Shahzad, Uswa; Stewart, Duncan J; Yau, Terrence M

    2014-11-01

    After ischemic injury, the endogenous repair mechanisms of the human heart are insufficient for meaningful tissue regeneration, so muscle lost is replaced by noncontractile scar tissue. Current treatments for ischemic cardiomyopathy improve quality of life and increase life expectancy, but cannot cure the underlying disease of cardiomyocyte loss. Cellular transplantation is emerging as a valuable therapeutic approach to heal the ischemic heart. Adult bone marrow stem cells are capable of differentiation, regeneration of infarcted myocardium, and induction of myogenesis and angiogenesis, ultimately leading to improved contractility. Positive results from animal studies have prompted several clinical trials to ascertain the safety and feasibility of cell therapy. However, despite all the excitement in stem cell research resulting from initial experimental data and preliminary clinical trials, the mixed results observed have raised many unanswered questions. A major obstacle to the identification of the optimal cell therapy is that the fate of the implanted cells and the nature of their beneficial effects are ill-defined. A better understanding is fundamental for the development of new therapeutic agents, and to optimize stem cell applications. Well-designed and powered double-blinded randomized studies are clearly needed to confirm promising findings from early studies. With several ongoing randomized trials directed toward evaluation of stem cell therapies in patients with acute or chronic ischemic cardiomyopathy, the Canadian initiative represents a milestone. Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  17. Purmorphamine as a Shh Signaling Activator Small Molecule Promotes Motor Neuron Differentiation of Mesenchymal Stem Cells Cultured on Nanofibrous PCL Scaffold.

    PubMed

    Bahrami, Naghmeh; Bayat, Mohammad; Mohamadnia, Abdolreza; Khakbiz, Mehrdad; Yazdankhah, Meysam; Ai, Jafar; Ebrahimi-Barough, Somayeh

    2017-09-01

    There is variety of stem cell sources but problems in ethical issues, contamination, and normal karyotype cause many limitations in obtaining and using these cells. The cells in Wharton's jelly region of umbilical cord are abundant and available stem cells with low immunological incompatibility, which could be considered for cell replacement therapy. Small molecules have been presented as less expensive biologically active compounds that can regulate different developmental process. Purmorphamine (PMA) is a small molecule that, according to some studies, possesses certain differentiation effects. In this study, we investigated the effect of the PMA on Wharton's jelly mesenchymal stem cell (WJ-MSC) differentiation into motor neuronal lineages instead of sonic hedgehog (Shh) on PCL scaffold. After exposing to induction media for 15 days, the cells were characterized for expression of motor neuron markers including PAX6, NF-H, Islet1, HB9, and choline acetyl transferase (ChAT) by quantitative reverse transcription (PCR) and immunocytochemistry. Our results demonstrated that induced WJ-MSCs with PMA could significantly express motor neuron markers in RNA and protein levels 15 days post induction. These results suggested that WJ-MSCs can differentiate to motor neuron-like cells with PMA on PCL scaffold and might provide a potential source in cell therapy for nervous system.

  18. A humanized system to expand in vitro amniotic fluid-derived stem cells intended for clinical application.

    PubMed

    Martinelli, Daniela; Pereira, Rui Cruz; Mogni, Massimo; Benelli, Roberto; Mastrogiacomo, Maddalena; Coviello, Domenico; Cancedda, Ranieri; Gentili, Chiara

    2016-03-01

    The amniotic fluid is a new source of multipotent stem cells with therapeutic potential for human diseases. In agreement with the regulatory requirement to reduce and possibly to avoid animal-derived reagents in the culture of cells intended for cell therapy, bovine serum, the most common supplement in the culture medium, was replaced by human platelet-derived growth factors. We tested a new culture medium to expand monolayers of human amniotic fluid stem cells (hAFSC) for clinical use. The AFSC were isolated by c-Kit selection and expanded in media supplemented with either bovine serum or a human platelet lysate (Lyset). We compared proliferation kinetics, colony-forming unit percentage, multilineage differentiation, immunophenotypic characterization and inhibition of peripheral blood mononuclear cell proliferation of the two AFSC cell cultures and we found no significant differences. Moreover, the karyotype analysis of the cells expanded in the presence of the platelet lysate did not present cytogenetic abnormalities and in vitro and in vivo studies revealed no cell tumorigenicity. Platelet derivatives represent a rich source of growth factors that can play a safety role in the homeostasis, proliferation and remodeling of tissue healing. We propose human platelet extracts as a preferential alternative to animal serum for the expansion of stem cells for clinical applications. Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  19. Effect of dental pulp stem cells in MPTP-induced old-aged mice model.

    PubMed

    Gnanasegaran, Nareshwaran; Govindasamy, Vijayendran; Simon, Christopher; Gan, Quan Fu; Vincent-Chong, Vui King; Mani, Vasudevan; Krishnan Selvarajan, Kesavanarayanan; Subramaniam, Vellayan; Musa, Sabri; Abu Kasim, Noor Hayaty

    2017-06-01

    Parkinson's disease (PD) is a neurodegenerative disease caused by the loss of dopaminergic (DA-ergic) neurons in the substantia nigra (SN) and represented as a huge threat to the geriatric population. Cell replacement therapies (CRTs) have been proposed as a promising strategy to slow down or replace neuronal loss. Among the widely available cell sources, dental pulp stem cells (DPSCs) portray as an attractive source primarily due to their neural crest origin, ease of tissue procurement and less ethical hurdles. We first demonstrated the in vitro differentiation ability of DPSCs towards DA-ergic-like cells before evaluating their neuro-protection/neuro-restoration capacities in MPTP-induced mice. Transplantation via intrathecal was performed with behavioural assessments being evaluated every fortnight. Subsequent analysis investigating their immuno-modulatory behaviour was conducted using neuronal and microglial cell lines. It was apparent that the behavioural parameters began to improve corresponding to tyrosine hydroxylase (TH), dopamine transporter (DAT) and dopamine decarboxylase (AADC) immunostaining in SN and striatum as early as 8-week post-transplantation (P < 0·05). About 60% restoration of DA-ergic neurons was observed at SN in MPTP-treated mice after 12-week post-transplantation. Similarly, their ability to reduce toxic effects of MPTP (DNA damages, reactive oxygen species and nitric oxide release) and regulate cytokine levels was distinctly noted (P < 0·05) upon exposure in in vitro model. Our results suggest that DPSCs may provide a therapeutic benefit in the old-aged PD mice model and may be explored in stem cell-based CRTs especially in geriatric population as an attempt towards 'personalized medicine'. © 2017 Stichting European Society for Clinical Investigation Journal Foundation.

  20. Homing and Tracking of Iron Oxide Labelled Mesenchymal Stem Cells After Infusion in Traumatic Brain Injury Mice: a Longitudinal In Vivo MRI Study.

    PubMed

    Mishra, Sushanta Kumar; Khushu, Subash; Singh, Ajay K; Gangenahalli, Gurudutta

    2018-06-17

    Stem cells transplantation has emerged as a promising alternative therapeutic due to its potency at injury site. The need to monitor and non-invasively track the infused stem cells is a significant challenge in the development of regenerative medicine. Thus, in vivo tracking to monitor infused stem cells is especially vital. In this manuscript, we have described an effective in vitro labelling method of MSCs, a serial in vivo tracking of implanted stem cells at traumatic brain injury (TBI) site through 7 T magnetic resonance imaging (MRI). Proper homing of infused MSCs was carried out at different time points using histological analysis and Prussian blue staining. Longitudinal in vivo tracking of infused MSCs were performed up to 21 days in different groups through MRI using relaxometry technique. Results demonstrated that MSCs incubated with iron oxide-poly-L-lysine complex (IO-PLL) at a ratio of 50:1.5 μg/ml and a time period of 6 h was optimised to increase labelling efficiency. T2*-weighted images and relaxation study demonstrated a significant signal loss and effective decrease in transverse relaxation time on day-3 at injury site after systemic transplantation, revealed maximum number of stem cells homing to the lesion area. MRI results further correlate with histological and Prussian blue staining in different time periods. Decrease in negative signal and increase in relaxation times were observed after day-14, may indicate damage tissue replacement with healthy tissue. MSCs tracking with synthesized negative contrast agent represent a great advantage during both in vitro and in vivo analysis. The proposed absolute bias correction based relaxometry analysis could be extrapolated for stem cell tracking and therapies in various neurodegenerative diseases.

  1. Wound-Induced Polyploidization: Regulation by Hippo and JNK Signaling and Conservation in Mammals.

    PubMed

    Losick, Vicki P; Jun, Albert S; Spradling, Allan C

    2016-01-01

    Tissue integrity and homeostasis often rely on the proliferation of stem cells or differentiated cells to replace lost, aged, or damaged cells. Recently, we described an alternative source of cell replacement- the expansion of resident, non-dividing diploid cells by wound-induced polyploidization (WIP). Here we show that the magnitude of WIP is proportional to the extent of cell loss using a new semi-automated assay with single cell resolution. Hippo and JNK signaling regulate WIP; unexpectedly however, JNK signaling through AP-1 limits rather than stimulates the level of Yki activation and polyploidization in the Drosophila epidermis. We found that polyploidization also quantitatively compensates for cell loss in a mammalian tissue, mouse corneal endothelium, where increased cell death occurs with age in a mouse model of Fuchs Endothelial Corneal Dystrophy (FECD). Our results suggest that WIP is an evolutionarily conserved homeostatic mechanism that maintains the size and synthetic capacity of adult tissues.

  2. Clinical potentials of human pluripotent stem cells.

    PubMed

    Mora, Cristina; Serzanti, Marialaura; Consiglio, Antonella; Memo, Maurizio; Dell'Era, Patrizia

    2017-08-01

    Aging, injuries, and diseases can be considered as the result of malfunctioning or damaged cells. Regenerative medicine aims to restore tissue homeostasis by repairing or replacing cells, tissues, or damaged organs, by linking and combining different disciplines including engineering, technology, biology, and medicine. To pursue these goals, the discipline is taking advantage of pluripotent stem cells (PSCs), a peculiar type of cell possessing the ability to differentiate into every cell type of the body. Human PSCs can be isolated from the blastocysts and maintained in culture indefinitely, giving rise to the so-called embryonic stem cells (ESCs). However, since 2006, it is possible to restore in an adult cell a pluripotent ESC-like condition by forcing the expression of four transcription factors with the rejuvenating reprogramming technology invented by Yamanaka. Then the two types of PSC can be differentiated, using standardized protocols, towards the cell type necessary for the regeneration. Although the use of these derivatives for therapeutic transplantation is still in the preliminary phase of safety and efficacy studies, a lot of efforts are presently taking place to discover the biological mechanisms underlying genetic pathologies, by differentiating induced PSCs derived from patients, and new therapies by challenging PSC-derived cells in drug screening.

  3. Progress in corneal wound healing

    PubMed Central

    Ljubimov, Alexander V.; Saghizadeh, Mehrnoosh

    2015-01-01

    Corneal wound healing is a complex process involving cell death, migration, proliferation, differentiation, and extracellular matrix remodeling. Many similarities are observed in the healing processes of corneal epithelial, stromal and endothelial cells, as well as cell-specific differences. Corneal epithelial healing largely depends on limbal stem cells and remodeling of the basement membrane. During stromal healing, keratocytes get transformed to motile and contractile myofibroblasts largely due to activation of transforming growth factor-β system. Endothelial cells heal mostly by migration and spreading, with cell proliferation playing a secondary role. In the last decade, many aspects of wound healing process in different parts of the cornea have been elucidated, and some new therapeutic approaches have emerged. The concept of limbal stem cells received rigorous experimental corroboration, with new markers uncovered and new treatment options including gene and microRNA therapy tested in experimental systems. Transplantation of limbal stem cell-enriched cultures for efficient re-epithelialization in stem cell deficiency and corneal injuries has become reality in clinical setting. Mediators and course of events during stromal healing have been detailed, and new treatment regimens including gene (decorin) and stem cell therapy for excessive healing have been designed. This is a very important advance given the popularity of various refractive surgeries entailing stromal wound healing. Successful surgical ways of replacing the diseased endothelium have been clinically tested, and new approaches to accelerate endothelial healing and suppress endothelial-mesenchymal transformation have been proposed including Rho kinase (ROCK) inhibitor eye drops and gene therapy to activate TGF-β inhibitor SMAD7. Promising new technologies with potential for corneal wound healing manipulation including microRNA, induced pluripotent stem cells to generate corneal epithelium, and nanocarriers for corneal drug delivery are discussed. Attention is also paid to problems in wound healing understanding and treatment, such as lack of specific epithelial stem cell markers, reliable identification of stem cells, efficient prevention of haze and stromal scar formation, lack of data on wound regulating microRNAs in keratocytes and endothelial cells, as well as virtual lack of targeted systems for drug and gene delivery to select corneal cells. PMID:26197361

  4. Progress in corneal wound healing.

    PubMed

    Ljubimov, Alexander V; Saghizadeh, Mehrnoosh

    2015-11-01

    Corneal wound healing is a complex process involving cell death, migration, proliferation, differentiation, and extracellular matrix remodeling. Many similarities are observed in the healing processes of corneal epithelial, stromal and endothelial cells, as well as cell-specific differences. Corneal epithelial healing largely depends on limbal stem cells and remodeling of the basement membrane. During stromal healing, keratocytes get transformed to motile and contractile myofibroblasts largely due to activation of transforming growth factor-β (TGF-β) system. Endothelial cells heal mostly by migration and spreading, with cell proliferation playing a secondary role. In the last decade, many aspects of wound healing process in different parts of the cornea have been elucidated, and some new therapeutic approaches have emerged. The concept of limbal stem cells received rigorous experimental corroboration, with new markers uncovered and new treatment options including gene and microRNA therapy tested in experimental systems. Transplantation of limbal stem cell-enriched cultures for efficient re-epithelialization in stem cell deficiency and corneal injuries has become reality in clinical setting. Mediators and course of events during stromal healing have been detailed, and new treatment regimens including gene (decorin) and stem cell therapy for excessive healing have been designed. This is a very important advance given the popularity of various refractive surgeries entailing stromal wound healing. Successful surgical ways of replacing the diseased endothelium have been clinically tested, and new approaches to accelerate endothelial healing and suppress endothelial-mesenchymal transformation have been proposed including Rho kinase (ROCK) inhibitor eye drops and gene therapy to activate TGF-β inhibitor SMAD7. Promising new technologies with potential for corneal wound healing manipulation including microRNA, induced pluripotent stem cells to generate corneal epithelium, and nanocarriers for corneal drug delivery are discussed. Attention is also paid to problems in wound healing understanding and treatment, such as lack of specific epithelial stem cell markers, reliable identification of stem cells, efficient prevention of haze and stromal scar formation, lack of data on wound regulating microRNAs in keratocytes and endothelial cells, as well as virtual lack of targeted systems for drug and gene delivery to select corneal cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Multi-kilobase homozygous targeted gene replacement in human induced pluripotent stem cells.

    PubMed

    Byrne, Susan M; Ortiz, Luis; Mali, Prashant; Aach, John; Church, George M

    2015-02-18

    Sequence-specific nucleases such as TALEN and the CRISPR/Cas9 system have so far been used to disrupt, correct or insert transgenes at precise locations in mammalian genomes. We demonstrate efficient 'knock-in' targeted replacement of multi-kilobase genes in human induced pluripotent stem cells (iPSC). Using a model system replacing endogenous human genes with their mouse counterpart, we performed a comprehensive study of targeting vector design parameters for homologous recombination. A 2.7 kilobase (kb) homozygous gene replacement was achieved in up to 11% of iPSC without selection. The optimal homology arm length was around 2 kb, with homology length being especially critical on the arm not adjacent to the cut site. Homologous sequence inside the cut sites was detrimental to targeting efficiency, consistent with a synthesis-dependent strand annealing (SDSA) mechanism. Using two nuclease sites, we observed a high degree of gene excisions and inversions, which sometimes occurred more frequently than indel mutations. While homozygous deletions of 86 kb were achieved with up to 8% frequency, deletion frequencies were not solely a function of nuclease activity and deletion size. Our results analyzing the optimal parameters for targeting vector design will inform future gene targeting efforts involving multi-kilobase gene segments, particularly in human iPSC. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  6. Intra-articular Implantation of Mesenchymal Stem Cells, Part 2

    PubMed Central

    Kraeutler, Matthew J.; Mitchell, Justin J.; Chahla, Jorge; McCarty, Eric C.; Pascual-Garrido, Cecilia

    2017-01-01

    Knee osteoarthritis (OA) after partial or total meniscectomy is a prevalent issue that patients must face. Various methods of replacing meniscal tissue have been studied to avoid this progression, including meniscal allograft transplantation, meniscal scaffolds, and synthetic meniscus replacement. Studies have shown that meniscal scaffolds may improve symptoms but have not been shown to prevent progression of OA. Recently, mesenchymal stem cells (MSCs) have been proposed as a possible biological therapy for meniscal regeneration. Several animal studies and 1 human study have evaluated the effect of transplanting MSCs into the knee joint after partial meniscectomy. The purpose of this review was to assess the outcomes of intra-articular transplantation of MSCs on meniscal regeneration in animals and humans after partial meniscectomy. Limited results from animal studies suggest that there is some potential for intra-articular injection of MSCs for the regeneration of meniscal tissue. However, further studies are necessary to determine the quality of regenerated meniscal tissue through histological and biomechanical testing. PMID:28203596

  7. Adenosine deaminase deficiency: a review.

    PubMed

    Flinn, Aisling M; Gennery, Andrew R

    2018-04-24

    Adenosine deaminase (ADA) deficiency leads to an accumulation of toxic purine degradation by-products, most potently affecting lymphocytes, leading to adenosine deaminase-deficient severe combined immunodeficiency. Whilst most notable affects are on lymphocytes, other manifestations include skeletal abnormalities, neurodevelopmental affects and pulmonary manifestations associated with pulmonary-alveolar proteinosis. Affected patients present in early infancy, usually with persistent infection, or with pulmonary insufficiency. Three treatment options are currently available. Initial treatment with enzyme replacement therapy may alleviate acute symptoms and enable partial immunological reconstitution, but treatment is life-long, immune reconstitution is incomplete, and the reconstituted immune system may nullify the effects of the enzyme replacement. Hematopoietic stem cell transplant has long been established as the treatment of choice, particularly where a matched sibling or well matched unrelated donor is available. More recently, the use of gene addition techniques to correct the genetic defect in autologous haematopoietic stem cells treatment has demonstrated immunological and clinical efficacy. This article reviews the biology, clinical presentation, diagnosis and treatment of ADA-deficiency.

  8. Neural stem cells rescue nervous purkinje neurons by restoring molecular homeostasis of tissue plasminogen activator and downstream targets.

    PubMed

    Li, Jianxue; Imitola, Jaime; Snyder, Evan Y; Sidman, Richard L

    2006-07-26

    Neural stem cells (NSCs) offer special therapeutic prospects because they can be isolated from the CNS, expanded ex vivo, and re-implanted into diseased CNS where they not only migrate and differentiate according to cues from host tissue but also appear to be capable of affecting host cells. In nervous (nr) mutant mice Purkinje neuron (PN) mitochondria become abnormal by the second postnatal week, and a majority of PNs die in the fourth to fifth weeks. We previously identified in nr cerebellum a 10-fold increase in tissue plasminogen activator (tPA) as a key component of the mechanism causing nr PN death. Here we report that undifferentiated wild-type murine NSCs, when transplanted into the newborn nr cerebellar cortex, do not replace host PNs but contact imperiled PNs and support their mitochondrial function, dendritic growth, and synaptogenesis, subsequently leading to the rescue of host PNs and restoration of motor coordination. This protection of nr PNs also is verified by an in vitro organotypic slice model in which nr cerebellar slices are cocultured with NSCs. Most importantly, the integrated NSCs in young nr cerebellum rectify excessive tPA mRNA and protein to close to normal levels and protect the mitochondrial voltage-dependent anion channel and neurotrophins, downstream targets of the tPA/plasmin proteolytic system. This report demonstrates for the first time that NSCs can rescue imperiled host neurons by rectifying their gene expression, elevating somatic stem cell therapeutic potential beyond solely cell replacement strategy.

  9. Tissue engineering in endodontics.

    PubMed

    Saber, Shehab El-Din M

    2009-12-01

    Tissue engineering is the science of design and manufacture of new tissues to replace impaired or damaged ones. The key ingredients for tissue engineering are stem cells, the morphogens or growth factors that regulate their differentiation, and a scaffold of extracellular matrix that constitutes the microenvironment for their growth. Recently, there has been increasing interest in applying the concept of tissue engineering to endodontics. The aim of this study was to review the body of knowledge related to dental pulp stem cells, the most common growth factors, and the scaffolds used to control their differentiation, and a clinical technique for the management of immature non-vital teeth based on this novel concept.

  10. Hydra as a tractable, long-lived model system for senescence

    PubMed Central

    Bellantuono, Anthony J.; Bridge, Diane; Martínez, Daniel E.

    2015-01-01

    Hydra represents a unique model system for the study of senescence, with the opportunity for the comparison of non-aging and induced senescence. Hydra maintains three stem cell lineages, used for continuous tissue morphogenesis and replacement. Recent work has elucidated the roles of the insulin/IGF-1 signaling target FoxO, of Myc proteins, and of PIWI proteins in Hydra stem cells. Under laboratory culture conditions, Hydra vulgaris show no signs of aging even under long-term study. In contrast, Hydra oligactis can be experimentally induced to undergo reproduction-associated senescence. This provides a powerful comparative system for future studies. PMID:26136619

  11. Genetic and Epigenetic Regulation of Human Cardiac Reprogramming and Differentiation in Regenerative Medicine

    PubMed Central

    Burridge, Paul W.; Sharma, Arun; Wu, Joseph C.

    2016-01-01

    Regeneration or replacement of lost cardiomyocytes within the heart has the potential to revolutionize cardiovascular medicine. Numerous methodologies have been used to achieve this aim, including the engraftment of bone marrow- and heart-derived cells as well as the identification of modulators of adult cardiomyocyte proliferation. Recently, the conversion of human somatic cells into induced pluripotent stem cells and induced cardiomyocyte-like cells has transformed potential approaches toward this goal, and the engraftment of cardiac progenitors derived from human embryonic stem cells into patients is now feasible. Here we review recent advances in our understanding of the genetic and epigenetic control of human cardiogenesis, cardiac differentiation, and the induced reprogramming of somatic cells to cardiomyocytes. We also cover genetic programs for inducing the proliferation of endogenous cardiomyocytes and discuss the genetic state of cells used in cardiac regenerative medicine. PMID:26631515

  12. The use of mesenchymal stem cells (MSCs) for amyotrophic lateral sclerosis (ALS) therapy - a perspective on cell biological mechanisms.

    PubMed

    Tang, Bor Luen

    2017-10-26

    Recent clinical trials of mesenchymal stem cells (MSCs) transplantation have demonstrated procedural safety and clinical proof of principle with a modest indication of benefit in patients with amyotrophic lateral sclerosis (ALS). While replacement therapy remained unrealistic, the clinical efficacy of this therapeutic option could be potentially enhanced if we could better decipher the mechanisms underlying some of the beneficial effects of transplanted cells, and work toward augmenting or combining these in a strategic manner. Novel ways whereby MSCs could act in modifying disease progression should also be explored. In this review, I discuss the known, emerging and postulated mechanisms of action underlying effects that transplanted MSCs may exert to promote motor neuron survival and/or to encourage regeneration in ALS. I shall also speculate on how transplanted cells may alter the diseased environment so as to minimize non-neuron cell autonomous damages by immune cells and astrocytes.

  13. Advances in hepatic stem/progenitor cell biology

    PubMed Central

    Verhulst, Stefaan; Best, Jan; van Grunsven, Leo A.; Dollé, Laurent

    2015-01-01

    The liver is famous for its strong regenerative capacity, employing different modes of regeneration according to type and extent of injury. Mature liver cells are able to proliferate in order to replace the damaged tissue allowing the recovery of the parenchymal function. In more severe scenarios hepatocytes are believed to arise also from a facultative liver progenitor cell compartment. In human, severe acute liver failure and liver cirrhosis are also both important clinical targets in which regeneration is impaired, where the role of this stem cell compartment seems more convincing. In animal models, the current state of ambiguity regarding the identity and role of liver progenitor cells in liver physiology dampens the enthusiasm for the potential use of these cells in regenerative medicine. The aim of this review is to give the basics of liver progenitor cell biology and discuss recent results vis-à-vis their identity and contribution to liver regeneration. PMID:26600740

  14. Translating G-CSF as an adjunct therapy to stem cell transplantation for stroke

    PubMed Central

    dela Peña, Ike; Borlongan, Cesar V.

    2015-01-01

    Among recently investigated stroke therapies, stem cell treatment holds great promise by virtue of their putative ability to replace lost cells, promote endogenous neurogenesis and produce behavioral and functional improvement through their “bystander effects.” Translating stem cell in the clinic, however, presents a number of technical difficulties. A strategy suggested to enhance therapeutic utility of stem cells is combination therapy, i.e., cotransplantation of stem cells or adjunct treatment with pharmacological agents and substrates, which is assumed to produce more profound therapeutic benefits by circumventing limitations of individual treatments, and facilitating complementary brain repair processes. We previously demonstrated enhanced functional effects of co-treatment with granulocyte-colony stimulating factor (G-CSF) and human umbilical cord blood cell (hUCB) transplantation in animal models of traumatic brain injury (TBI). Here, we suggest that the aforementioned combination therapy may also produce synergistic effects in stroke. Accordingly, G-CSF treatment may reduce expression of pro-inflammatory cytokines and enhance neurogenesis rendering a receptive microenvironment for hUCB engraftment. Adjunct treatment of G-CSF with hUCB may facilitate stemness maintenance and guide neural lineage commitment of hUCB cells. Moreover, regenerative mechanisms afforded by G-CSF-mobilized endogenous stem cells, secretion of growth factors by hUCB grafts and G-CSF-recruited endothelial progenitor cells (EPCs) , as well as the potential graft–host integration that may promote synaptic circuitry re-establishment could altogether produce more pronounced functional improvement in stroked rats subjected to a combination G-CSF treatment and hUCB transplantation. Nevertheless, differences in pathology and repair processes underlying TBI and stroke deserve consideration when testing effects of combinatorial G-CSF and hUCB cell transplantation for stroke treatment. Further studies are also required to determine safety and efficacy of this intervention in both preclinical and clinical stroke studies. PMID:26482176

  15. Reversible Block of Mouse Neural Stem Cell Differentiation in the Absence of Dicer and MicroRNAs

    PubMed Central

    Sansom, Stephen N.; Alsiö, Jessica M.; Kaneda, Masahiro; Smith, James; O'Carroll, Donal; Tarakhovsky, Alexander; Livesey, Frederick J.

    2010-01-01

    Background To investigate the functions of Dicer and microRNAs in neural stem (NS) cell self-renewal and neurogenesis, we established neural stem cell lines from the embryonic mouse Dicer-null cerebral cortex, producing neural stem cell lines that lacked all microRNAs. Principal Findings Dicer-null NS cells underwent normal self-renewal and could be maintained in vitro indefinitely, but had subtly altered cell cycle kinetics and abnormal heterochromatin organisation. In the absence of all microRNAs, Dicer-null NS cells were incapable of generating either glial or neuronal progeny and exhibited a marked dependency on exogenous EGF for survival. Dicer-null NS cells assumed complex differences in mRNA and protein expression under self-renewing conditions, upregulating transcripts indicative of self-renewing NS cells and expressing genes characteristic of differentiating neurons and glia. Underlining the growth-factor dependency of Dicer-null NS cells, many regulators of apoptosis were enriched in expression in these cells. Dicer-null NS cells initiate some of the same gene expression changes as wild-type cells under astrocyte differentiating conditions, but also show aberrant expression of large sets of genes and ultimately fail to complete the differentiation programme. Acute replacement of Dicer restored their ability to differentiate to both neurons and glia. Conclusions The block in differentiation due to loss of Dicer and microRNAs is reversible and the significantly altered phenotype of Dicer-null NS cells does not constitute a permanent transformation. We conclude that Dicer and microRNAs function in this system to maintain the neural stem cell phenotype and to facilitate the completion of differentiation. PMID:20976144

  16. Expression of polysialylated neural cell adhesion molecules on adult stem cells after neuronal differentiation of inner ear spiral ganglion neurons

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Park, Kyoung Ho; Yeo, Sang Won, E-mail: swyeo@catholic.ac.kr; Troy, Frederic A., E-mail: fatroy@ucdavis.edu

    Highlights: • PolySia expressed on neurons primarily during early stages of neuronal development. • PolySia–NCAM is expressed on neural stem cells from adult guinea pig spiral ganglion. • PolySia is a biomarker that modulates neuronal differentiation in inner ear stem cells. - Abstract: During brain development, polysialylated (polySia) neural cell adhesion molecules (polySia–NCAMs) modulate cell–cell adhesive interactions involved in synaptogenesis, neural plasticity, myelination, and neural stem cell (NSC) proliferation and differentiation. Our findings show that polySia–NCAM is expressed on NSC isolated from adult guinea pig spiral ganglion (GPSG), and in neurons and Schwann cells after differentiation of the NSC withmore » epidermal, glia, fibroblast growth factors (GFs) and neurotrophins. These differentiated cells were immunoreactive with mAb’s to polySia, NCAM, β-III tubulin, nestin, S-100 and stained with BrdU. NSC could regenerate and be differentiated into neurons and Schwann cells. We conclude: (1) polySia is expressed on NSC isolated from adult GPSG and on neurons and Schwann cells differentiated from these NSC; (2) polySia is expressed on neurons primarily during the early stage of neuronal development and is expressed on Schwann cells at points of cell–cell contact; (3) polySia is a functional biomarker that modulates neuronal differentiation in inner ear stem cells. These new findings suggest that replacement of defective cells in the inner ear of hearing impaired patients using adult spiral ganglion neurons may offer potential hope to improve the quality of life for patients with auditory dysfunction and impaired hearing disorders.« less

  17. Developmental insights from early mammalian embryos and core signaling pathways that influence human pluripotent cell growth and differentiation.

    PubMed

    Chen, Kevin G; Mallon, Barbara S; Johnson, Kory R; Hamilton, Rebecca S; McKay, Ronald D G; Robey, Pamela G

    2014-05-01

    Human pluripotent stem cells (hPSCs) have two potentially attractive applications: cell replacement-based therapies and drug discovery. Both require the efficient generation of large quantities of clinical-grade stem cells that are free from harmful genomic alterations. The currently employed colony-type culture methods often result in low cell yields, unavoidably heterogeneous cell populations, and substantial chromosomal abnormalities. Here, we shed light on the structural relationship between hPSC colonies/embryoid bodies and early-stage embryos in order to optimize current culture methods based on the insights from developmental biology. We further highlight core signaling pathways that underlie multiple epithelial-to-mesenchymal transitions (EMTs), cellular heterogeneity, and chromosomal instability in hPSCs. We also analyze emerging methods such as non-colony type monolayer (NCM) and suspension culture, which provide alternative growth models for hPSC expansion and differentiation. Furthermore, based on the influence of cell-cell interactions and signaling pathways, we propose concepts, strategies, and solutions for production of clinical-grade hPSCs, stem cell precursors, and miniorganoids, which are pivotal steps needed for future clinical applications. Published by Elsevier B.V.

  18. Hepatic veno-occlusive disease in pediatric stem cell transplantation: impact of pre-emptive antithrombin III replacement and combined antithrombin III/defibrotide therapy.

    PubMed

    Haussmann, Ursula; Fischer, Joachim; Eber, Stefan; Scherer, Franziska; Seger, Reinhard; Gungor, Tayfun

    2006-06-01

    Hepatic veno-occlusive disease (VOD) remains a serious complication after hematopoietic stem cell transplantation (HSCT). Based on a protective effect of antithrombin III (ATIII) on endothelial cells, we assessed the incidence of VOD after pre-emptive ATIII replacement and the outcome of VOD after combined high dose defibrotide (DF) and ATIII therapy. This prospective case series comprised two phases. In the first phase 71 children did not receive any specific VOD prophylaxis or therapy (controls). In the second phase 91 children were given pre-emptive ATIII replacement in case of decreased ATIII activity (< or =70%). If VOD was diagnosed clinically (according to modified Seattle criteria), high dose defibrotide (60 mg/day) and ATIII replacement therapy were combined. The severity of VOD was determined according to the degree of multiple organ dysfunction. The incidence of VOD was similar in both groups (13/71, 18% vs. 14/91, 15%). All 14 patients in the second group who developed VOD showed decreased ATIII activity not more than 1 day prior to the clinical diagnosis of VOD. The resulting short duration of pre-emptive ATIII therapy failed to prevent VOD (OR 0.96). None of the patients (n=72) maintaining normal ATIII levels developed VOD. All 14 patients with VOD who received combined therapy achieved complete remission and 93 % (13/14) survived until day +100, compared to six survivors (46%) in the first group. Pre-emptive ATIII administration did not alter the incidence of VOD. Combination treatment with ATIII and defibrotide was safe and yielded excellent remission and survival rates.

  19. Recent advances and future directions in the management of knee osteoarthritis: Can biological joint reconstruction replace joint arthroplasty and when?

    PubMed Central

    Paschos, Nikolaos K

    2015-01-01

    In this article, a concise description of the recent advances in the field of osteoarthritis management is presented. The main focus is to highlight the most promising techniques that emerge in both biological joint replacement and artificial joint arthroplasty. A critical view of high quality evidence regarding outcome and safety profile of these techniques is presented. The potential role of kinematically aligned total knee replacement, navigation, and robotic-assisted surgery is outlined. A critical description of both primary and stem cell-based therapies, the cell homing theory, the use of biologic factors and recent advancements in tissue engineering and regenerative medicine is provided. Based on the current evidence, some thoughts on a realistic approach towards answering these questions are attempted. PMID:26495242

  20. Tissue engineering as innovative chance for organ replacement in radical tumor surgery.

    PubMed

    Alberti, C

    2013-03-01

    Different pathological conditions such as congenital organ absence, severe organ injuries, end-stage organ failure and malignancy-related organ removal, have few effective therapeutic options a part from a whole organ transplant, that, however, often meets with a serious shortage of suitable donor organs. The purpose of this paper consists in highlighting what the novel tissue engineering approaches might help to solve such problems. EMERGING CONCEPTS: A recent approach in tissue/organ engineering, particularly to build bioartificial airways, is the procedure of decellularizing a whole donor organ to obtain a complex 3D-biomatrix-scaffold maintaining the intrinsic vascular network, that is subsequently recellularized with recipient's autologous organ-specific differentiated cells or/and stem cells, to build a potentially functional biological substitute. Such strategy has been clinically used to replace organ in trachea/broncus tumor patients. In another approach, mainly used to construct a bioartificial urinary bladder tissue, different types of either biodegradable synthetic polymers or naturally-derived matrices or even polymer/biomatrix-composite materials are used as scaffold for either cell-free or autologous cell-seeded tissue engineering procedures. So far, such technique has been mainly used to make an augmentation cystoplasty in patients with end-stage poorly compliant neuropathic bladder or in exstrophic bladder subjects. Intriguing developments in biomaterial science, nanotechnologies, stem cell biology, and further improvements in bioreactor manufacturing will allow to generate, in the near future, tissue engineered organs that, as for structure/function so the native one-like, might represent the optimum solution to replace organs in tumor surgery.

  1. Transgene Reactivation in Induced Pluripotent Stem Cell Derivatives and Reversion to Pluripotency of Induced Pluripotent Stem Cell-Derived Mesenchymal Stem Cells

    PubMed Central

    Galat, Yekaterina; Perepitchka, Mariana; Jennings, Lawrence J.; Iannaccone, Philip M.; Hendrix, Mary J.C.

    2016-01-01

    Induced pluripotent stem cells (iPSCs) have enormous potential in regenerative medicine and disease modeling. It is now felt that clinical trials should be performed with iPSCs derived with nonintegrative constructs. Numerous studies, however, including those describing disease models, are still being published using cells derived from iPSCs generated with integrative constructs. Our experimental work presents the first evidence of spontaneous transgene reactivation in vitro in several cellular types. Our results show that the transgenes were predominantly silent in parent iPSCs, but in mesenchymal and endothelial iPSC derivatives, the transgenes experienced random upregulation of Nanog and c-Myc. Additionally, we provide evidence of spontaneous secondary reprogramming and reversion to pluripotency in mesenchymal stem cells derived from iPSCs. These findings strongly suggest that the studies, which use cellular products derived from iPSCs generated with retro- or lentiviruses, should be evaluated with consideration of the possibility of transgene reactivation. The in vitro model described here provides insight into the earliest events of culture transformation and suggests the hypothesis that reversion to pluripotency may be responsible for the development of tumors in cell replacement experiments. The main goal of this work, however, is to communicate the possibility of transgene reactivation in retro- or lenti-iPSC derivatives and the associated loss of cellular fidelity in vitro, which may impact the outcomes of disease modeling and related experimentation. PMID:27193052

  2. Changes in human bone marrow fat content associated with changes in hematopoietic stem cell numbers and cytokine levels with aging

    PubMed Central

    Tuljapurkar, Sonal R; McGuire, Timothy R; Brusnahan, Susan K; Jackson, John D; Garvin, Kevin L; Kessinger, Margaret A; Lane, Judy T; O' Kane, Barbara J; Sharp, John G

    2011-01-01

    Hematological deficiencies increase with aging, including anemias, reduced responses to hematopoietic stress and myelodysplasias. This investigation tested the hypothesis that increased bone marrow (BM) fat content in humans with age was associated with decreased numbers of side population (SP) hematopoietic stem cells, and this decrease correlated with changes in cytokine levels. BM was obtained from the femoral head and trochanteric region of the femur removed at surgery for total hip replacement (N = 100 subjects). In addition, BM from cadavers (N = 36), with no evidence of hip disease, was evaluated for fat content. Whole trabecular marrow samples were ground in a sterile mortar and pestle, and cellularity and lipid content determined. Marrow cells were stained with Hoechst dye and SP profiles were acquired. Plasma levels of insulin-like growth factor (IGF)-1, stromal-derived factor (SDF)-1 and interleukin (IL)-6 were measured using ELISA. Fat content in the BM of human subjects and cadavers increased with age. The numbers of SP stem cells in BM as well as plasma IGF-1 and SDF-1 levels decreased in correlation with increased BM fat. IL-6 had no relationship to changes in marrow fat. These data suggest that increased BM fat may be associated with a decreased number of SP stem cells and IGF-1 and SDF-1 levels with aging. These data further raise a more general question as to the role of adipose cells in the regulation of tissue stem cells. PMID:21923862

  3. Role of nanotopography in the development of tissue engineered 3D organs and tissues using mesenchymal stem cells.

    PubMed

    Salmasi, Shima; Kalaskar, Deepak M; Yoon, Wai-Weng; Blunn, Gordon W; Seifalian, Alexander M

    2015-03-26

    Recent regenerative medicine and tissue engineering strategies (using cells, scaffolds, medical devices and gene therapy) have led to fascinating progress of translation of basic research towards clinical applications. In the past decade, great deal of research has focused on developing various three dimensional (3D) organs, such as bone, skin, liver, kidney and ear, using such strategies in order to replace or regenerate damaged organs for the purpose of maintaining or restoring organs' functions that may have been lost due to aging, accident or disease. The surface properties of a material or a device are key aspects in determining the success of the implant in biomedicine, as the majority of biological reactions in human body occur on surfaces or interfaces. Furthermore, it has been established in the literature that cell adhesion and proliferation are, to a great extent, influenced by the micro- and nano-surface characteristics of biomaterials and devices. In addition, it has been shown that the functions of stem cells, mesenchymal stem cells in particular, could be regulated through physical interaction with specific nanotopographical cues. Therefore, guided stem cell proliferation, differentiation and function are of great importance in the regeneration of 3D tissues and organs using tissue engineering strategies. This review will provide an update on the impact of nanotopography on mesenchymal stem cells for the purpose of developing laboratory-based 3D organs and tissues, as well as the most recent research and case studies on this topic.

  4. Concise Review: Mesenchymal Stem Cells for Functional Cartilage Tissue Engineering: Taking Cues from Chondrocyte‐Based Constructs

    PubMed Central

    Tan, Andrea R.

    2017-01-01

    Abstract Osteoarthritis, the most prevalent form of joint disease, afflicts 9% of the U.S. population over the age of 30 and costs the economy nearly $100 billion annually in healthcare and socioeconomic costs. It is characterized by joint pain and dysfunction, though the pathophysiology remains largely unknown. Due to its avascular nature and limited cellularity, articular cartilage exhibits a poor intrinsic healing response following injury. As such, significant research efforts are aimed at producing engineered cartilage as a cell‐based approach for articular cartilage repair. However, the knee joint is mechanically demanding, and during injury, also a milieu of harsh inflammatory agents. The unforgiving mechano‐chemical environment requires tissue replacements that are capable of bearing such burdens. The use of mesenchymal stem cells (MSCs) for cartilage tissue engineering has emerged as a promising cell source due to their ease of isolation, capacity to readily expand in culture, and ability to undergo lineage‐specific differentiation into chondrocytes. However, to date, very few studies utilizing MSCs have successfully recapitulated the structural and functional properties of native cartilage, exposing the difficult process of uniformly differentiating stem cells into desired cell fates and maintaining the phenotype during in vitro culture and after in vivo implantation. To address these shortcomings, here, we present a concise review on modulating stem cell behavior, tissue development and function using well‐developed techniques from chondrocyte‐based cartilage tissue engineering. Stem Cells Translational Medicine 2017;6:1295–1303 PMID:28177194

  5. Epigenomics in hematopoietic transplantation: novel treatment strategies.

    PubMed

    Engel, Nicole; Rank, Andreas

    2011-10-01

    Allogeneic hematopoietic stem cell transplantation is a high risk but curative treatment option for leukemia, myelodysplasia and other hematological malignancies. After high dose radio- or chemo-therapy, recipient's hematopoiesis is replaced by a new immunosystem and residual malignant cells are eliminated by the graft-versus-leukemia reaction. The benefit of this immunological effect is limited by the most frequent complication of hematopoietic stem cell transplantation: graft-versus-host disease. In addition to their well-known anti-tumor activity, epigenetic drugs mediate immunotolerance without reducing alloreactivity or even enhance graft-versus-leukemia effect without inducing graft-versus-host disease by regulating cytokine release, increasing the circulating number of regulatory T cells and interacting with natural killer cells. We focus on the use of epigenetic drugs in the allogeneic transplantation setting in relation to their anti-tumor and immunomodulatory potential.

  6. Differentiation of Human Dental Pulp Stem Cells into Dopaminergic Neuron-like Cells in Vitro.

    PubMed

    Chun, So Young; Soker, Shay; Jang, Yu-Jin; Kwon, Tae Gyun; Yoo, Eun Sang

    2016-02-01

    We investigated the potential of human dental pulp stem cells (hDPSCs) to differentiate into dopaminergic neurons in vitro as an autologous stem cell source for Parkinson's disease treatment. The hDPSCs were expanded in knockout-embryonic stem cell (KO-ES) medium containing leukemia inhibitory factor (LIF) on gelatin-coated plates for 3-4 days. Then, the medium was replaced with KO-ES medium without LIF to allow the formation of the neurosphere for 4 days. The neurosphere was transferred into ITS medium, containing ITS (human insulin-transferrin-sodium) and fibronectin, to select for Nestin-positive cells for 6-8 days. The cells were then cultured in N-2 medium containing basic fibroblast growth factor (FGF), FGF-8b, sonic hedgehog-N, and ascorbic acid on poly-l-ornithine/fibronectin-coated plates to expand the Nestin-positive cells for up to 2 weeks. Finally, the cells were transferred into N-2/ascorbic acid medium to allow for their differentiation into dopaminergic neurons for 10-15 days. The differentiation stages were confirmed by morphological, immunocytochemical, flow cytometric, real-time PCR, and ELISA analyses. The expressions of mesenchymal stem cell markers were observed at the early stages. The expressions of early neuronal markers were maintained throughout the differentiation stages. The mature neural markers showed increased expression from stage 3 onwards. The percentage of cells positive for tyrosine hydroxylase was 14.49%, and the amount was 0.526 ± 0.033 ng/mL at the last stage. hDPSCs can differentiate into dopaminergic neural cells under experimental cell differentiation conditions, showing potential as an autologous cell source for the treatment of Parkinson's disease.

  7. A Protocol for Decellularizing Mouse Cochleae for Inner Ear Tissue Engineering.

    PubMed

    Neal, Christopher A; Nelson-Brantley, Jennifer G; Detamore, Michael S; Staecker, Hinrich; Mellott, Adam J

    2018-01-01

    In mammals, mechanosensory hair cells that facilitate hearing lack the ability to regenerate, which has limited treatments for hearing loss. Current regenerative medicine strategies have focused on transplanting stem cells or genetic manipulation of surrounding support cells in the inner ear to encourage replacement of damaged stem cells to correct hearing loss. Yet, the extracellular matrix (ECM) may play a vital role in inducing and maintaining function of hair cells, and has not been well investigated. Using the cochlear ECM as a scaffold to grow adult stem cells may provide unique insights into how the composition and architecture of the extracellular environment aids cells in sustaining hearing function. Here we present a method for isolating and decellularizing cochleae from mice to use as scaffolds accepting perfused adult stem cells. In the current protocol, cochleae are isolated from euthanized mice, decellularized, and decalcified. Afterward, human Wharton's jelly cells (hWJCs) that were isolated from the umbilical cord were carefully perfused into each cochlea. The cochleae were used as bioreactors, and cells were cultured for 30 days before undergoing processing for analysis. Decellularized cochleae retained identifiable extracellular structures, but did not reveal the presence of cells or noticeable fragments of DNA. Cells perfused into the cochlea invaded most of the interior and exterior of the cochlea and grew without incident over a duration of 30 days. Thus, the current method can be used to study how cochlear ECM affects cell development and behavior.

  8. Culture of porcine embryonic germ cells in serum-supplemented and serum-free conditions: the effects of serum and growth factors on primary and long-term culture.

    PubMed

    Petkov, Stoyan G; Anderson, Gary B

    2008-06-01

    Fetal bovine serum (FBS) is a commonly used medium supplement with variable and undefined composition, which presents problems in culture of pluripotent stem cells. The purpose of this study was to determine if FBS can be replaced with Knockout Serum Replacement (KSR), a defined medium supplement, and to examine the effects of FBS and growth factors on short- and long-term culture of pig embryonic germ cells (EGC). No significant differences were observed in total and mean colony areas in primary cultures between FBS- and KSR-supplemented medium (421 x 10(3) mum(2) vs. 395 x 10(3) microm(2), p = 0.68, n = 11, and 6375 microm(2) vs. 6407 microm(2), p = 0.885, respectively). Total and mean colony areas were significantly larger in KSR-supplemented medium compared with medium supplemented with KSR and growth factors (505 x 10(3) microm(2) vs. 396 x 10(3) microm(2), p = 0.016, n = 12, and 8769 microm(2) vs. 6513 microm(2), p = 0.003, respectively). The cultures proliferated for significantly higher numbers of passages in FBS-supplemented medium and in medium supplemented with KSR and growth factors compared with medium containing KSR alone (31.1 vs. 21.9, p = 0.004, n = 10, and 35.5 vs. 21.6, p = 002, n = 10, respectively). Porcine EGC maintained in serum-free conditions were positive for pluripotent stem cell markers, maintained stable karyotypes for up to 54 passages, and were capable of differentiating in vitro into cells from the three primary germ layers. These results will help improve and standardize culture of pluripotent stem cells in the pig.

  9. Bioengineered Tooth Buds Exhibit Features of Natural Tooth Buds.

    PubMed

    Smith, E E; Angstadt, S; Monteiro, N; Zhang, W; Khademhosseini, A; Yelick, P C

    2018-06-01

    Tooth loss is a significant health issue currently affecting millions of people worldwide. Artificial dental implants, the current gold standard tooth replacement therapy, do not exhibit many properties of natural teeth and can be associated with complications leading to implant failure. Here we propose bioengineered tooth buds as a superior alternative tooth replacement therapy. We describe improved methods to create highly cellularized bioengineered tooth bud constructs that formed hallmark features that resemble natural tooth buds such as the dental epithelial stem cell niche, enamel knot signaling centers, transient amplifying cells, and mineralized dental tissue formation. These constructs were composed of postnatal dental cells encapsulated within a hydrogel material that were implanted subcutaneously into immunocompromised rats. To our knowledge, this is the first report describing the use of postnatal dental cells to create bioengineered tooth buds that exhibit evidence of these features of natural tooth development. We propose future bioengineered tooth buds as a promising, clinically relevant tooth replacement therapy.

  10. WNT-C59, a Small-Molecule WNT Inhibitor, Efficiently Induces Anterior Cortex That Includes Cortical Motor Neurons From Human Pluripotent Stem Cells.

    PubMed

    Motono, Makoto; Ioroi, Yoshihiko; Ogura, Takenori; Takahashi, Jun

    2016-04-01

    The recapitulation of human neural development in a controlled, defined manner from pluripotent stem cells (PSCs) has considerable potential for studies of human neural development, circuit formation and function, and the construction of in vitro models of neurological diseases. The inhibition of Wnt signaling, often by the recombinant protein DKK1, is important for the induction of cortical neurons. Here, we report a novel differentiation method using a small-molecule WNT inhibitor, WNT-C59 (C59), to efficiently induce human anterior cortex. We compared two types of small molecules, C59 and XAV939 (XAV), as substitutes for DKK1 to induce cortical neurons from PSCs in serum-free embryoid body-like aggregate culture. DKK1 and XAV inhibited only the canonical pathway of Wnt signaling, whereas C59 inhibited both the canonical and noncanonical pathways. C59 efficiently induced CTIP2+/COUP-TF1- cells, which are characteristic of the cells found in the anterior cortex. In addition, when grafted into the cortex of adult mice, the C59-induced cells showed abundant axonal fiber extension toward the spinal cord. These results raise the possibility of C59 contributing to cell replacement therapy for motor neuron diseases or insults. For a cell therapy against damaged corticospinal tract caused by neurodegenerative diseases or insults, cortical motor neurons are needed. Currently, their induction from pluripotent stem cells is considered very promising; however, an efficient protocol to induce motor neurons is not available. For efficient induction of anterior cortex, where motor neurons are located, various WNT inhibitors were investigated. It was found that one of them could induce anterior cortical cells efficiently. In addition, when grafted into the cortex of adult mice, the induced cells showed more abundant axonal fiber extension toward spinal cord. These results raise the possibility that this inhibitor contributes to a cell-replacement therapy for motor neuron diseases or insults. ©AlphaMed Press.

  11. Wound healing potential of adipose tissue stem cell extract.

    PubMed

    Na, You Kyung; Ban, Jae-Jun; Lee, Mijung; Im, Wooseok; Kim, Manho

    2017-03-25

    Adipose tissue stem cells (ATSCs) are considered as a promising source in the field of cell therapy and regenerative medicine. In addition to direct cell replacement using stem cells, intercellular molecule exchange by stem cell secretory factors showed beneficial effects by reducing tissue damage and augmentation of endogenous repair. Delayed cutaneous wound healing is implicated in many conditions such as diabetes, aging, stress and alcohol consumption. However, the effects of cell-free extract of ATSCs (ATSC-Ex) containing secretome on wound healing process have not been investigated. In this study, ATSC-Ex was topically applied on the cutaneous wound and healing speed was examined. As a result, wound closure was much faster in the cell-free extract treated wound than control wound at 4, 6, 8 days after application of ATSC-Ex. Dermal fibroblast proliferation, migration and extracellular matrix (ECM) production are critical aspects of wound healing, and the effects of ATSC-Ex on human dermal fibroblast (HDF) was examined. ATSC-Ex augmented HDF proliferation in a dose-dependent manner and migration ability was enhanced by extract treatment. Representative ECM proteins, collagen type I and matrix metalloproteinase-1, are significantly up-regulated by treatment of ATSC-Ex. Our results suggest that the ATSC-Ex have improving effect of wound healing and can be the potential therapeutic candidate for cutaneous wound healing. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Isolation, identification and multipotential differentiation of mouse adipose tissue-derived stem cells.

    PubMed

    Taha, Masoumeh Fakhr; Hedayati, Vahideh

    2010-08-01

    Bone marrow and adipose tissue have provided two suitable sources of mesenchymal stem cells. Although previous studies have confirmed close similarities between bone marrow-derived stem cells (BM-MSCs) and adipose tissue-derived stem cells (ADSCs), the molecular phenotype of ADSCs is still poorly identified. In the present study, mouse ADSCs were isolated from the inguinal fat pad of 12-14 weeks old mice. Freshly isolated and three passaged ADSCs were analyzed for the expression of OCT4, Sca-1, c-kit and CD34 by RT-PCR. Three passaged ADSCs were analyzed by flow cytometry for the presence of CD11b, CD45, CD31, CD29 and CD44. Moreover, cardiogenic, adipogenic and neurogenic differentiation of ADSCs were induced in vitro. Freshly isolated ADSCs showed the expression of OCT4, Sca-1, c-kit and CD34, and two days cultured ADSCs were positively immunostained with anti-OCT4 monoclonal antibody. After three passages, the expression of OCT4, c-kit and CD34 eliminated, while the expression of Sca-1 showed a striking enhancement. These cells were identified positive for CD29 and CD44 markers, and they showed the lack of CD45 and CD31 expression. Three passaged ADSCs were differentiated to adipocyte-, cardiomyocyte- and neuron-like cells that were identified based on the positive staining with Sudan black, anti-cardiac troponin I antibody and anti-map-2 antibody, respectively. In conclusion, adipose tissue contains a stem cell population that seems to be a good multipotential cell candidate for the future cell replacement therapy. Copyright 2010 Elsevier Ltd. All rights reserved.

  13. The Spleen as an Optimal Site for Islet Transplantation and a Source of Mesenchymal Stem Cells.

    PubMed

    Sakata, Naoaki; Yoshimatsu, Gumpei; Kodama, Shohta

    2018-05-07

    This review demonstrates the unique potential of the spleen as an optimal site for islet transplantation and as a source of mesenchymal stem cells. Islet transplantation is a cellular replacement therapy used to treat severe diabetes mellitus; however, its clinical outcome is currently unsatisfactory. Selection of the most appropriate transplantation site is a major factor affecting the clinical success of this therapy. The spleen has long been studied as a candidate site for islet transplantation. Its advantages include physiological insulin drainage and regulation of immunity, and it has recently also been shown to contribute to the regeneration of transplanted islets. However, the efficacy of transplantation in the spleen is lower than that of intraportal transplantation, which is the current representative method of clinical islet transplantation. Safer and more effective methods of islet transplantation need to be established to allow the spleen to be used for clinical transplantation. The spleen is also of interest as a mesenchymal stem cell reservoir. Splenic mesenchymal stem cells contribute to the repair of damaged tissue, and their infusion may thus be a promising therapy for autoimmune diseases, including type 1 diabetes mellitus and Sjogren’s syndrome.

  14. Integrin-binding elastin-like polypeptide as an in situ gelling delivery matrix enhances the therapeutic efficacy of adipose stem cells in healing full-thickness cutaneous wounds.

    PubMed

    Choi, Seong-Kyoon; Park, Jin-Kyu; Kim, Jung-Hee; Lee, Kyeong-Min; Kim, Enjoo; Jeong, Kyu-Shik; Jeon, Won Bae

    2016-09-10

    One crucial issue in stem cell therapy used for tissue repair is often the lack of selective carriers to deliver stem cells to the site of injury where the native extracellular matrix is pathologically damaged or lost. Therefore, it is necessary to develop a biomaterial that is permissive to stem cells and is suitable to replace injured or missing matrix. The major aim of this study is to investigate the potential of an RGD-containing elastin-like polypeptide (REP) with the structure TGPG[VGRGD(VGVPG)6]20WPC to engraft adipose stem cells (ASC) to full-thickness excisional wounds in mice. We implanted REP into the wound defects via body temperature-induced in situ aggregation. Engrafted REP exhibited a half-life of 2.6days in the wounds and did not elicit any pathological immune responses. REP itself significantly accelerated wound closure and reepithelialization and upregulated the expression of dermal tissue components. A combined administration of REP and ASC formed a hydrogel-like ASC/REP composite, which provided better neovascularization than the use of ASCs alone and increased the viability of transplanted ASC, improving overall wound healing. In vitro and in vivo mechanistic investigations suggested that REP enhances ASC survival at least in part via the Fak/Src adhesion-induced upregulation of Mek/Erk and PI3K/Akt survival pathways. We conclude that REP is a promising therapeutic agent for the improvement of stem cell-based therapy for enhanced tissue regeneration and repair. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Isolation of Human Induced Pluripotent Stem Cell-Derived Dopaminergic Progenitors by Cell Sorting for Successful Transplantation

    PubMed Central

    Doi, Daisuke; Samata, Bumpei; Katsukawa, Mitsuko; Kikuchi, Tetsuhiro; Morizane, Asuka; Ono, Yuichi; Sekiguchi, Kiyotoshi; Nakagawa, Masato; Parmar, Malin; Takahashi, Jun

    2014-01-01

    Summary Human induced pluripotent stem cells (iPSCs) can provide a promising source of midbrain dopaminergic (DA) neurons for cell replacement therapy for Parkinson’s disease. However, iPSC-derived donor cells inevitably contain tumorigenic or inappropriate cells. Here, we show that human iPSC-derived DA progenitor cells can be efficiently isolated by cell sorting using a floor plate marker, CORIN. We induced DA neurons using scalable culture conditions on human laminin fragment, and the sorted CORIN+ cells expressed the midbrain DA progenitor markers, FOXA2 and LMX1A. When transplanted into 6-OHDA-lesioned rats, the CORIN+ cells survived and differentiated into midbrain DA neurons in vivo, resulting in significant improvement of the motor behavior, without tumor formation. In particular, the CORIN+ cells in a NURR1+ cell-dominant stage exhibited the best survival and function as DA neurons. Our method is a favorable strategy in terms of scalability, safety, and efficiency and may be advantageous for clinical application. PMID:24672756

  16. Tissue engineering and cell-based therapy toward integrated strategy with artificial organs.

    PubMed

    Gojo, Satoshi; Toyoda, Masashi; Umezawa, Akihiro

    2011-09-01

    Research in order that artificial organs can supplement or completely replace the functions of impaired or damaged tissues and internal organs has been underway for many years. The recent clinical development of implantable left ventricular assist devices has revolutionized the treatment of patients with heart failure. The emerging field of regenerative medicine, which uses human cells and tissues to regenerate internal organs, is now advancing from basic and clinical research to clinical application. In this review, we focus on the novel biomaterials, i.e., fusion protein, and approaches such as three-dimensional and whole-organ tissue engineering. We also compare induced pluripotent stem cells, directly reprogrammed cardiomyocytes, and somatic stem cells for cell source of future cell-based therapy. Integrated strategy of artificial organ and tissue engineering/regenerative medicine should give rise to a new era of medical treatment to organ failure.

  17. Human embryonic stem cell-derived oligodendrocyte progenitor cell transplants remyelinate and restore locomotion after spinal cord injury.

    PubMed

    Keirstead, Hans S; Nistor, Gabriel; Bernal, Giovanna; Totoiu, Minodora; Cloutier, Frank; Sharp, Kelly; Steward, Oswald

    2005-05-11

    Demyelination contributes to loss of function after spinal cord injury, and thus a potential therapeutic strategy involves replacing myelin-forming cells. Here, we show that transplantation of human embryonic stem cell (hESC)-derived oligodendrocyte progenitor cells (OPCs) into adult rat spinal cord injuries enhances remyelination and promotes improvement of motor function. OPCs were injected 7 d or 10 months after injury. In both cases, transplanted cells survived, redistributed over short distances, and differentiated into oligodendrocytes. Animals that received OPCs 7 d after injury exhibited enhanced remyelination and substantially improved locomotor ability. In contrast, when OPCs were transplanted 10 months after injury, there was no enhanced remyelination or locomotor recovery. These studies document the feasibility of predifferentiating hESCs into functional OPCs and demonstrate their therapeutic potential at early time points after spinal cord injury.

  18. Insights into skeletal muscle development and applications in regenerative medicine.

    PubMed

    Tran, T; Andersen, R; Sherman, S P; Pyle, A D

    2013-01-01

    Embryonic and postnatal development of skeletal muscle entails highly regulated processes whose complexity continues to be deconstructed. One key stage of development is the satellite cell, whose niche is composed of multiple cell types that eventually contribute to terminally differentiated myotubes. Understanding these developmental processes will ultimately facilitate treatments of myopathies such as Duchenne muscular dystrophy (DMD), a disease characterized by compromised cell membrane structure, resulting in severe muscle wasting. One theoretical approach is to use pluripotent stem cells in a therapeutic setting to help replace degenerated muscle tissue. This chapter discusses key myogenic developmental stages and their regulatory pathways; artificial myogenic induction in pluripotent stem cells; advantages and disadvantages of DMD animal models; and therapeutic approaches targeting DMD. Furthermore, skeletal muscle serves as an excellent paradigm for understanding general cell fate decisions throughout development. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Methods to Manipulate and Monitor Wnt Signaling in Human Pluripotent Stem Cells.

    PubMed

    Huggins, Ian J; Brafman, David; Willert, Karl

    2016-01-01

    Human pluripotent stem cells (hPSCs) may revolutionize medical practice by providing: (a) a renewable source of cells for tissue replacement therapies, (b) a powerful system to model human diseases in a dish, and (c) a platform for examining efficacy and safety of novel drugs. Furthermore, these cells offer a unique opportunity to study early human development in vitro, in particular, the process by which a seemingly uniform cell population interacts to give rise to the three main embryonic lineages: ectoderm, endoderm. and mesoderm. This process of lineage allocation is regulated by a number of inductive signals that are mediated by growth factors, including FGF, TGFβ, and Wnt. In this book chapter, we introduce a set of tools, methods, and protocols to specifically manipulate the Wnt signaling pathway with the intention of altering the cell fate outcome of hPSCs.

  20. Integration of stem cell-derived exosomes with in situ hydrogel glue as a promising tissue patch for articular cartilage regeneration.

    PubMed

    Liu, Xiaolin; Yang, Yunlong; Li, Yan; Niu, Xin; Zhao, Bizeng; Wang, Yang; Bao, Chunyan; Xie, Zongping; Lin, Qiuning; Zhu, Linyong

    2017-03-30

    The regeneration of articular cartilage, which scarcely shows innate self-healing ability, is a great challenge in clinical treatment. Stem cell-derived exosomes (SC-Exos), an important type of extracellular nanovesicle, exhibit great potential for cartilage regeneration to replace stem cell-based therapy. Cartilage regeneration often takes a relatively long time and there is currently no effective administration method to durably retain exosomes at cartilage defect sites to effectively exert their reparative effect. Therefore, in this study, we exploited a photoinduced imine crosslinking hydrogel glue, which presents excellent operation ability, biocompatibility and most importantly, cartilage-integration, as an exosome scaffold to prepare an acellular tissue patch (EHG) for cartilage regeneration. It was found that EHG can retain SC-Exos and positively regulate both chondrocytes and hBMSCs in vitro. Furthermore, EHG can integrate with native cartilage matrix and promote cell deposition at cartilage defect sites, finally resulting in the promotion of cartilage defect repair. The EHG tissue patch therefore provides a novel, cell-free scaffold material for wound repair.

  1. Lineage plasticity and cell biology of fibrocartilage and hyaline cartilage: its significance in cartilage repair and replacement.

    PubMed

    Freemont, Anthony J; Hoyland, Judith

    2006-01-01

    Cartilage repair is a major goal of modern tissue engineering. To produce novel engineered implants requires a knowledge of the basic biology of the tissues that are to be replaced or reproduced. Hyaline articular cartilage and meniscal fibrocartilage are two tissues that have excited attention because of the frequency with which they are damaged. A basic strategy is to re-engineer these tissues ex vivo by stimulating stem cells to differentiate into the cells of the mature tissue capable of producing an intact functional matrix. In this brief review, the sources of cells for tissue engineering cartilage and the culture conditions that have promoted differentiation are discussed within the context of natural cartilage repair. In particular, the role of cell density, cytokines, load, matrices and oxygen tension are discussed.

  2. Detection of negative and positive RNA strand of poliovirus Sabin 1 and echovirus E19 by a stem-loop reverse transcription PCR.

    PubMed

    Fikatas, A; Dimitriou, T G; Kyriakopoulou, Z; Moschonas, G D; Amoutzias, G D; Mossialos, D; Gartzonika, C; Levidiotou-Stefanou, S; Markoulatos, P

    2017-09-01

    In this report a strand specific RT-PCR was established for the detection of the replicative negative RNA strand of poliovirus sabin 1 (Sabin1) and Echovirus 19 (E19) strains. The key for the successful conduction of the assay was the use of a specific reverse transcription primer targeting the 5'-UTR of enteroviruses that consisted of a stem-loop structure at the 5'-end and an enteroviral-specific sequence at the 3'-end. The stem loop RT-PCR was found to be an accurate and sensitive method, detecting even 10 -2 CCID 50 of poliovirus sabin 1 (Sabin1) and E19 strains 6 h postinfection (p.i.), while CPE appeared 3 days later. This assay was also validated in SiHa and Caski cell lines that are not used for the detection of enteroviruses. The negative RNA strand was detected 6 h and 12 h p.i. in SiHa and Caski cells, when these cell lines were inoculated with 10 5 and 1 CCID 50 respectively, whereas CPE was observed 5 days p.i for SiHa cells and 8 days p.i for Caski cells and that only at 10 5 CCID 50 . The results show that this approach may be used for replacing the time-consuming cell cultures in order to detect the active replication of enteroviruses. Enteroviruses are positive stranded RNA viruses that may cause severe diseases. The conventional method for detection of active viral replication involves virus isolation in sensitive cell cultures followed by titration and seroneutralization. In this report, we describe the use of a stem-loop secondary structured oligonucleotide in RT-PCR assay for the detection of the replicative negative strand of the positive-stranded RNA of poliovirus sabin 1 and E19 strains. This approach proved to be a useful tool that may be used for replacing the time-consuming cell culture assays in order to detect the active replication of enteroviruses. © 2017 The Society for Applied Microbiology.

  3. Hematopoietic Gene Therapies for Metabolic and Neurologic Diseases.

    PubMed

    Biffi, Alessandra

    2017-10-01

    Increasingly, patients affected by metabolic diseases affecting the central nervous system and neuroinflammatory disorders receive hematopoietic cell transplantation (HCT) in the attempt to slow the course of their disease, delay or attenuate symptoms, and improve pathologic findings. The possible replacement of brain-resident myeloid cells by the transplanted cell progeny contributes to clinical benefit. Genetic engineering of the cells to be transplanted (hematopoietic stem cell) may endow the brain myeloid progeny of these cells with enhanced or novel functions, contributing to therapeutic effects. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Cellular programming and reprogramming: sculpting cell fate for the production of dopamine neurons for cell therapy.

    PubMed

    Aguila, Julio C; Hedlund, Eva; Sanchez-Pernaute, Rosario

    2012-01-01

    Pluripotent stem cells are regarded as a promising cell source to obtain human dopamine neurons in sufficient amounts and purity for cell replacement therapy. Importantly, the success of clinical applications depends on our ability to steer pluripotent stem cells towards the right neuronal identity. In Parkinson disease, the loss of dopamine neurons is more pronounced in the ventrolateral population that projects to the sensorimotor striatum. Because synapses are highly specific, only neurons with this precise identity will contribute, upon transplantation, to the synaptic reconstruction of the dorsal striatum. Thus, understanding the developmental cell program of the mesostriatal dopamine neurons is critical for the identification of the extrinsic signals and cell-intrinsic factors that instruct and, ultimately, determine cell identity. Here, we review how extrinsic signals and transcription factors act together during development to shape midbrain cell fates. Further, we discuss how these same factors can be applied in vitro to induce, select, and reprogram cells to the mesostriatal dopamine fate.

  5. Pancreatic differentiation of Pdx1-GFP reporter mouse induced pluripotent stem cells.

    PubMed

    Porciuncula, Angelo; Kumar, Anujith; Rodriguez, Saray; Atari, Maher; Araña, Miriam; Martin, Franz; Soria, Bernat; Prosper, Felipe; Verfaillie, Catherine; Barajas, Miguel

    2016-12-01

    Efficient induction of defined lineages in pluripotent stem cells constitutes the determinant step for the generation of therapeutically relevant replacement cells to potentially treat a wide range of diseases, including diabetes. Pancreatic differentiation has remained an important challenge in large part because of the need to differentiate uncommitted pluripotent stem cells into highly specialized hormone-secreting cells, which has been shown to require a developmentally informed step-by-step induction procedure. Here, in the framework of using induced pluripotent stem cells (iPSCs) to generate pancreatic cells for pancreatic diseases, we have generated and characterized iPSCs from Pdx1-GFP transgenic mice. The use of a GFP reporter knocked into the endogenous Pdx1 promoter allowed us to monitor pancreatic induction based on the expression of Pdx1, a pancreatic master transcription factor, and to isolate a pure Pdx1-GFP + population for downstream applications. Differentiated cultures timely expressed markers specific to each stage and end-stage progenies acquired a rather immature beta-cell phenotype, characterized by polyhormonal expression even among cells highly expressing the Pdx1-GFP reporter. Our findings highlight the utility of employing a fluorescent protein reporter under the control of a master developmental gene in order to devise novel differentiation protocols for relevant cell types for degenerative diseases such as pancreatic beta cells for diabetes. Copyright © 2016 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  6. Biodistribution of Liver-Derived Mesenchymal Stem Cells After Peripheral Injection in a Hemophilia A Patient.

    PubMed

    Sokal, Etienne M; Lombard, Catherine Anne; Roelants, Véronique; Najimi, Mustapha; Varma, Sharat; Sargiacomo, Camillo; Ravau, Joachim; Mazza, Giuseppe; Jamar, François; Versavau, Julia; Jacobs, Vanessa; Jacquemin, Marc; Eeckhoudt, Stéphane; Lambert, Catherine; Stéphenne, Xavier; Smets, Françoise; Hermans, Cédric

    2017-08-01

    With the exception of liver transplantation, there is no cure for hemophilia, which is currently managed by preemptive replacement therapy. Liver-derived stem cells are in clinical development for inborn and acquired liver diseases and could represent a curative treatment for hemophilia A. The liver is a major factor VIII (FVIII) synthesis site, and mesenchymal stem cells have been shown to control joint bleeding in animal models of hemophilia. Adult-derived human liver stem cells (ADHLSCs) have mesenchymal characteristics and have been shown able to engraft in and repopulate both animal and human livers. Thus, the objectives were to evaluate the potency of ADHLSCs to control bleeding in a hemophilia A patient and assess the biodistribution of the cells after intravenous injection. A patient suffering from hemophilia A was injected with repeated doses of ADHLSCs via a peripheral vein (35 million In-oxine-labeled cells, followed by 125 million cells the next day, and 3 infusions of 250 million cells every 2 weeks thereafter; total infusion period, 50 days). After cell therapy, we found a temporary (15 weeks) decrease in the patient's FVIII requirements and severe bleeding complications, despite a lack of increase in circulating FVIII. The cells were safely administered to the patient via a peripheral vein. Biodistribution analysis revealed an initial temporary entrapment of the cells in the lungs, followed by homing to the liver and to a joint afflicted with hemarthrosis. These results suggest the potential use of ADHLSCs in the treatment of hemophilia A.

  7. Laser bioprinting of human induced pluripotent stem cells-the effect of printing and biomaterials on cell survival, pluripotency, and differentiation.

    PubMed

    Koch, Lothar; Deiwick, Andrea; Franke, Annika; Schwanke, Kristin; Haverich, Axel; Zweigerdt, Robert; Chichkov, Boris

    2018-04-25

    Research on human induced pluripotent stem cells (hiPSCs) is one of the fastest growing fields in biomedicine. Generated from patient's own somatic cells, hiPSCs can be differentiated towards all functional cell types and returned to the patient without immunological concerns. 3D printing of hiPSCs could enable the generation of functional organs for replacement therapies or realization of organ-on-chip systems for individualized medicine. Printing of living cells was demonstrated with immortalized cell lines, primary cells, and adult stem cells with different printing technologies and biomaterials. However, hiPSCs are more sensitive to handling procedures, in particular, when dissociated into single cells. Both pluripotency and directed differentiation are influenced by numerous environmental factors including culture media, biomaterials, and cell density. Notably, existing literature on the effect of applied biomaterials on pluripotency is rather ambiguous. In this study, laser bioprinting of undifferentiated hiPSCs in combination with different biomaterials was performed and the impact on cells' behavior, pluripotency, and differentiation was investigated. Our findings suggest that hiPSCs are indeed more sensitive to the applied biomaterials, but not to laser printing itself. With appropriate biomaterials, such as the hyaluronic acid based solutions applied in this study, hiPSCs can be successfully laser printed without losing their pluripotency.

  8. Cftr gene targeting in mouse embryonic stem cells mediated by Small Fragment Homologous Replacement (SFHR).

    PubMed

    Sangiuolo, Federica; Scaldaferri, Maria Lucia; Filareto, Antonio; Spitalieri, Paola; Guerra, Lorenzo; Favia, Maria; Caroppo, Rosa; Mango, Ruggiero; Bruscia, Emanuela; Gruenert, Dieter C; Casavola, Valeria; De Felici, Massimo; Novelli, Giuseppe

    2008-01-01

    Different gene targeting approaches have been developed to modify endogenous genomic DNA in both human and mouse cells. Briefly, the process involves the targeting of a specific mutation in situ leading to the gene correction and the restoration of a normal gene function. Most of these protocols with therapeutic potential are oligonucleotide based, and rely on endogenous enzymatic pathways. One gene targeting approach, "Small Fragment Homologous Replacement (SFHR)", has been found to be effective in modifying genomic DNA. This approach uses small DNA fragments (SDF) to target specific genomic loci and induce sequence and subsequent phenotypic alterations. This study shows that SFHR can stably introduce a 3-bp deletion (deltaF508, the most frequent cystic fibrosis (CF) mutation) into the Cftr (CF Transmembrane Conductance Regulator) locus in the mouse embryonic stem (ES) cell genome. After transfection of deltaF508-SDF into murine ES cells, SFHR-mediated modification was evaluated at the molecular levels on DNA and mRNA obtained from transfected ES cells. About 12% of transcript corresponding to deleted allele was detected, while 60% of the electroporated cells completely lost any measurable CFTR-dependent chloride efflux. The data indicate that the SFHR technique can be used to effectively target and modify genomic sequences in ES cells. Once the SFHR-modified ES cells differentiate into different cell lineages they can be useful for elucidating tissue-specific gene function and for the development of transplantation-based cellular and therapeutic protocols.

  9. Progress of mesenchymal stem cell therapy for neural and retinal diseases

    PubMed Central

    Ng, Tsz Kin; Fortino, Veronica R; Pelaez, Daniel; Cheung, Herman S

    2014-01-01

    Complex circuitry and limited regenerative power make central nervous system (CNS) disorders the most challenging and difficult for functional repair. With elusive disease mechanisms, traditional surgical and medical interventions merely slow down the progression of the neurodegenerative diseases. However, the number of neurons still diminishes in many patients. Recently, stem cell therapy has been proposed as a viable option. Mesenchymal stem cells (MSCs), a widely-studied human adult stem cell population, have been discovered for more than 20 years. MSCs have been found all over the body and can be conveniently obtained from different accessible tissues: bone marrow, blood, and adipose and dental tissue. MSCs have high proliferative and differentiation abilities, providing an inexhaustible source of neurons and glia for cell replacement therapy. Moreover, MSCs also show neuroprotective effects without any genetic modification or reprogramming. In addition, the extraordinary immunomodulatory properties of MSCs enable autologous and heterologous transplantation. These qualities heighten the clinical applicability of MSCs when dealing with the pathologies of CNS disorders. Here, we summarize the latest progress of MSC experimental research as well as human clinical trials for neural and retinal diseases. This review article will focus on multiple sclerosis, spinal cord injury, autism, glaucoma, retinitis pigmentosa and age-related macular degeneration. PMID:24772238

  10. Progress of mesenchymal stem cell therapy for neural and retinal diseases.

    PubMed

    Ng, Tsz Kin; Fortino, Veronica R; Pelaez, Daniel; Cheung, Herman S

    2014-04-26

    Complex circuitry and limited regenerative power make central nervous system (CNS) disorders the most challenging and difficult for functional repair. With elusive disease mechanisms, traditional surgical and medical interventions merely slow down the progression of the neurodegenerative diseases. However, the number of neurons still diminishes in many patients. Recently, stem cell therapy has been proposed as a viable option. Mesenchymal stem cells (MSCs), a widely-studied human adult stem cell population, have been discovered for more than 20 years. MSCs have been found all over the body and can be conveniently obtained from different accessible tissues: bone marrow, blood, and adipose and dental tissue. MSCs have high proliferative and differentiation abilities, providing an inexhaustible source of neurons and glia for cell replacement therapy. Moreover, MSCs also show neuroprotective effects without any genetic modification or reprogramming. In addition, the extraordinary immunomodulatory properties of MSCs enable autologous and heterologous transplantation. These qualities heighten the clinical applicability of MSCs when dealing with the pathologies of CNS disorders. Here, we summarize the latest progress of MSC experimental research as well as human clinical trials for neural and retinal diseases. This review article will focus on multiple sclerosis, spinal cord injury, autism, glaucoma, retinitis pigmentosa and age-related macular degeneration.

  11. Early wound healing of laser in situ keratomileusis-like flaps after treatment with human corneal stromal stem cells.

    PubMed

    Morgan, Siân R; Dooley, Erin P; Kamma-Lorger, Christina; Funderburgh, James L; Funderburgh, Martha L; Meek, Keith M

    2016-02-01

    To use a well-established organ culture model to investigate the effects of corneal stromal stem cells on the optical and biomechanical properties of corneal wounds after laser in situ keratomileusis (LASIK)-like flap creation. School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales, United Kingdom. Experimental study. The LASIK-like flaps were produced in sheep corneas. The flap beds were treated with corneal stromal stem cells and were then replaced and allowed to heal for different periods of up to 3 weeks in organ culture. The optical transmission of the cornea, the force required to detach the flap, and the presence of myofibroblasts near the flap bed were measured. Corneal stromal stem cell-treated flap beds were statistically significantly more transparent after 3 weeks in culture than the untreated controls. At 3 weeks, the mean force necessary to detach the flap was more than twice the force required for the respective control samples. Concurrently, there were 44% activated cells immediately below the flap margin of the controls compared with 29% in the same region of the corneal stromal stem cell-treated flaps. In this system, the presence of corneal stromal stem cells at the wound margin significantly increased the adherence of LASIK-like flaps while maintaining corneal transparency. It is postulated that this is achieved by the deposition of extracellular connective tissue similar to that found in the normal cornea and by the paucity of activated keratocytes (myofibroblasts), which are known to scatter a significant amount of the incident light. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Survival of partially differentiated mouse embryonic stem cells in the scala media of the guinea pig cochlea.

    PubMed

    Hildebrand, Michael S; Dahl, Hans-Henrik M; Hardman, Jennifer; Coleman, Bryony; Shepherd, Robert K; de Silva, Michelle G

    2005-12-01

    The low regenerative capacity of the hair cells of the mammalian inner ear is a major obstacle for functional recovery following sensorineural hearing loss. A potential treatment is to replace damaged tissue by transplantation of stem cells. To test this approach, undifferentiated and partially differentiated mouse embryonic stem (ES) cells were delivered into the scala media of the deafened guinea pig cochlea. Transplanted cells survived in the scala media for a postoperative period of at least nine weeks, evidenced by histochemical and direct fluorescent detection of enhanced green fluorescent protein (EGFP). Transplanted cells were discovered near the spiral ligament and stria vascularis in the endolymph fluid of the scala media. In some cases, cells were observed close to the damaged organ of Corti structure. There was no evidence of significant immunological rejection of the implanted ES cells despite the absence of immunosuppression. Our surgical approach allowed efficient delivery of ES cells to the scala media while preserving the delicate structures of the cochlea. This is the first report of the survival of partially differentiated ES cells in the scala media of the mammalian cochlea, and it provides support for the potential of cell-based therapies for sensorineural hearing impairment.

  13. Survival of Partially Differentiated Mouse Embryonic Stem Cells in the Scala Media of the Guinea Pig Cochlea

    PubMed Central

    Hildebrand, Michael S.; Dahl, Hans-Henrik M.; Hardman, Jennifer; Coleman, Bryony; Shepherd, Robert K.

    2005-01-01

    The low regenerative capacity of the hair cells of the mammalian inner ear is a major obstacle for functional recovery following sensorineural hearing loss. A potential treatment is to replace damaged tissue by transplantation of stem cells. To test this approach, undifferentiated and partially differentiated mouse embryonic stem (ES) cells were delivered into the scala media of the deafened guinea pig cochlea. Transplanted cells survived in the scala media for a postoperative period of at least nine weeks, evidenced by histochemical and direct fluorescent detection of enhanced green fluorescent protein (EGFP). Transplanted cells were discovered near the spiral ligament and stria vascularis in the endolymph fluid of the scala media. In some cases, cells were observed close to the damaged organ of Corti structure. There was no evidence of significant immunological rejection of the implanted ES cells despite the absence of immunosuppression. Our surgical approach allowed efficient delivery of ES cells to the scala media while preserving the delicate structures of the cochlea. This is the first report of the survival of partially differentiated ES cells in the scala media of the mammalian cochlea, and it provides support for the potential of cell-based therapies for sensorineural hearing impairment. PMID:16208453

  14. Development of Defective and Persistent Sendai Virus Vector

    PubMed Central

    Nishimura, Ken; Sano, Masayuki; Ohtaka, Manami; Furuta, Birei; Umemura, Yoko; Nakajima, Yoshiro; Ikehara, Yuzuru; Kobayashi, Toshihiro; Segawa, Hiroaki; Takayasu, Satoko; Sato, Hideyuki; Motomura, Kaori; Uchida, Eriko; Kanayasu-Toyoda, Toshie; Asashima, Makoto; Nakauchi, Hiromitsu; Yamaguchi, Teruhide; Nakanishi, Mahito

    2011-01-01

    The ectopic expression of transcription factors can reprogram differentiated tissue cells into induced pluripotent stem cells. However, this is a slow and inefficient process, depending on the simultaneous delivery of multiple genes encoding essential reprogramming factors and on their sustained expression in target cells. Moreover, once cell reprogramming is accomplished, these exogenous reprogramming factors should be replaced with their endogenous counterparts for establishing autoregulated pluripotency. Complete and designed removal of the exogenous genes from the reprogrammed cells would be an ideal option for satisfying this latter requisite as well as for minimizing the risk of malignant cell transformation. However, no single gene delivery/expression system has ever been equipped with these contradictory characteristics. Here we report the development of a novel replication-defective and persistent Sendai virus (SeVdp) vector based on a noncytopathic variant virus, which fulfills all of these requirements for cell reprogramming. The SeVdp vector could accommodate up to four exogenous genes, deliver them efficiently into various mammalian cells (including primary tissue cells and human hematopoietic stem cells) and express them stably in the cytoplasm at a prefixed balance. Furthermore, interfering with viral transcription/replication using siRNA could erase the genomic RNA of SeVdp vector from the target cells quickly and thoroughly. A SeVdp vector installed with Oct4/Sox2/Klf4/c-Myc could reprogram mouse primary fibroblasts quite efficiently; ∼1% of the cells were reprogrammed to Nanog-positive induced pluripotent stem cells without chromosomal gene integration. Thus, this SeVdp vector has potential as a tool for advanced cell reprogramming and for stem cell research. PMID:21138846

  15. Gene delivery in tissue engineering and regenerative medicine.

    PubMed

    Fang, Y L; Chen, X G; W T, Godbey

    2015-11-01

    As a promising strategy to aid or replace tissue/organ transplantation, gene delivery has been used for regenerative medicine applications to create or restore normal function at the cell and tissue levels. Gene delivery has been successfully performed ex vivo and in vivo in these applications. Excellent proliferation capabilities and differentiation potentials render certain cells as excellent candidates for ex vivo gene delivery for regenerative medicine applications, which is why multipotent and pluripotent cells have been intensely studied in this vein. In this review, gene delivery is discussed in detail, along with its applications to tissue engineering and regenerative medicine. A definition of a stem cell is compared to a definition of a stem property, and both provide the foundation for an in-depth look at gene delivery investigations from a germ lineage angle. © 2014 Wiley Periodicals, Inc.

  16. Stem/progenitor cells derived from the cochlear sensory epithelium give rise to spheres with distinct morphologies and features.

    PubMed

    Diensthuber, Marc; Oshima, Kazuo; Heller, Stefan

    2009-06-01

    Nonmammalian vertebrates regenerate lost sensory hair cells by means of asymmetric division of supporting cells. Inner ear or lateral line supporting cells in birds, amphibians, and fish consequently serve as bona fide stem cells resulting in high regenerative capacity of hair cell-bearing organs. Hair cell regeneration does not happen in the mammalian cochlea, but cells with proliferative capacity can be isolated from the neonatal cochlea. These cells have the ability to form clonal floating colonies, so-called spheres, when cultured in nonadherent conditions. We noticed that the sphere population derived from mouse cochlear sensory epithelium cells was heterogeneous, consisting of morphologically distinct sphere types, hereby classified as solid, transitional, and hollow. Cochlear sensory epithelium-derived stem/progenitor cells initially give rise to small solid spheres, which subsequently transition into hollow spheres, a change that is accompanied by epithelial differentiation of the majority of sphere cells. Only solid spheres, and to a lesser extent, transitional spheres, appeared to harbor self-renewing stem cells, whereas hollow spheres could not be consistently propagated. Solid spheres contained significantly more rapidly cycling Pax-2-expressing presumptive otic progenitor cells than hollow spheres. Islet-1, which becomes upregulated in nascent sensory patches, was also more abundant in solid than in hollow spheres. Likewise, hair cell-like cells, characterized by the expression of multiple hair cell markers, differentiated in significantly higher numbers in cell populations derived from solid spheres. We conclude that cochlear sensory epithelium cell populations initially give rise to small solid spheres that have self-renewing capacity before they subsequently convert into hollow spheres, a process that is accompanied by loss of stemness and reduced ability to spontaneously give rise to hair cell-like cells. Solid spheres might, therefore, represent the most suitable sphere type for cell-based assays or animal model transplantation studies aimed at development of cell replacement therapies.

  17. [Nuclear transfer and therapeutic cloning].

    PubMed

    Xu, Xiao-Ming; Lei, An-Min; Hua, Jin-Lian; Dou, Zhong-Ying

    2005-03-01

    Nuclear transfer and therapeutic cloning have widespread and attractive prospects in animal agriculture and biomedical applications. We reviewed that the quality of oocytes and nuclear reprogramming of somatic donor cells were the main reasons of the common abnormalities in cloned animals and the low efficiency of cloning and showed the problems and outlets in therapeutic cloning, such as some basic problems in nuclear transfer affected clinical applications of therapeutic cloning. Study on isolation and culture of nuclear transfer embryonic stem (ntES) cells and specific differentiation of ntES cells into important functional cells should be emphasized and could enhance the efficiency. Adult stem cells could help to cure some great diseases, but could not replace therapeutic cloning. Ethics also impeded the development of therapeutic cloning. It is necessary to improve many techniques and reinforce the research of some basic theories, then somatic nuclear transfer and therapeutic cloning may apply to agriculture reproduction and benefit to human life better.

  18. Clinical Application of Induced Pluripotent Stem Cells in Cardiovascular Medicine.

    PubMed

    Chi, Hong-jie; Gao, Song; Yang, Xin-chun; Cai, Jun; Zhao, Wen-shu; Sun, Hao; Geng, Yong-Jian

    2015-01-01

    Induced pluripotent stem cells (iPSCs) are generated by reprogramming human somatic cells through the overexpression of four transcription factors: Oct4, Sox2, Klf4 and c-Myc. iPSCs are capable of indefinite self-renewal, and they can differentiate into almost any type of cell in the body. These cells therefore offer a highly valuable therapeutic strategy for tissue repair and regeneration. Recent experimental and preclinical research has revealed their potential for cardiovascular disease diagnosis, drug screening and cellular replacement therapy. Nevertheless, significant challenges remain in terms of the development and clinical application of human iPSCs. Here, we review current progress in research related to patient-specific iPSCs for ex vivo modeling of cardiovascular disorders and drug screening, and explore the potential of human iPSCs for use in the field of cardiovascular regenerative medicine. © 2015 S. Karger AG, Basel.

  19. Which has more stem-cell characteristics: Müller cells or Müller cells derived from in vivo culture in neurospheres?

    PubMed

    Ji, Hong-Pei; Xiong, Yu; Zhang, En-Dong; Song, Wei-Tao; Gao, Zhao-Lin; Yao, Fei; Sun, Hong; Zhou, Rong-Rong; Xia, Xiao-Bo

    2017-01-01

    Müller cells can be acquired from in vitro culture or a neurosphere culture system. Both culture methods yield cells with progenitor-cell characteristics that can differentiate into mature nervous cells. We compared the progenitor-cell traits of Müller cells acquired from each method. Primary murine Müller cells were isolated in serum culture media and used to generate Müller cells derived from neurospheres in serum-free culture conditions. Gene expression of neural progenitor cell markers was examined by Q-PCR in the two groups. Expression of rhodopsin and the cone-rod homeobox protein CRX were assessed after induction with 1 μM all-trans retinoic acid (RA) for 7 days. After more than four passages, many cells were large, flattened, and difficult to passage. A spontaneously immortalized Müller cell line was not established. Three-passage neurospheres yielded few new spheres. Genes coding for Nestin, Sox2, Chx10, and Vimentin were downregulated in cells derived from neurospheres compared to the cells from standard culture, while Pax6 was upregulated. Müller cells from both culture methods were induced into rod photoreceptors, but expression of rhodopsin and CRX was greater in the Müller cells from the standard culture. Both culture methods yielded cells with stem-cell characteristics that can be induced into rod photoreceptor neurons by RA. Serum had no influence on the "stemness" of the cells. Cells from standard culture had greater "stemness" than cells derived from neurospheres. The standard Müller cells would seem to be the best choice for transplantation in cell replacement therapy for photoreceptor degeneration.

  20. Disease modeling using human induced pluripotent stem cells: lessons from the liver.

    PubMed

    Gieseck, Richard L; Colquhoun, Jennifer; Hannan, Nicholas R F

    2015-01-01

    Human pluripotent stem cells (hPSCs) have the capacity to differentiate into any of the hundreds of distinct cell types that comprise the human body. This unique characteristic has resulted in considerable interest in the field of regenerative medicine, given the potential for these cells to be used to protect, repair, or replace diseased, injured, and aged cells within the human body. In addition to their potential in therapeutics, hPSCs can be used to study the earliest stages of human development and to provide a platform for both drug screening and disease modeling using human cells. Recently, the description of human induced pluripotent stem cells (hIPSCs) has allowed the field of disease modeling to become far more accessible and physiologically relevant, as pluripotent cells can be generated from patients of any genetic background. Disease models derived from hIPSCs that manifest cellular disease phenotypes have been established to study several monogenic diseases; furthermore, hIPSCs can be used for phenotype-based drug screens to investigate complex diseases for which the underlying genetic mechanism is unknown. As a result, the use of stem cells as research tools has seen an unprecedented growth within the last decade as researchers look for in vitro disease models which closely mimic in vivo responses in humans. Here, we discuss the beginnings of hPSCs, starting with isolation of human embryonic stem cells, moving into the development and optimization of hIPSC technology, and ending with the application of hIPSCs towards disease modeling and drug screening applications, with specific examples highlighting the modeling of inherited metabolic disorders of the liver. This article is part of a Special Issue entitled Linking transcription to physiology in lipodomics. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  1. TOOTH (The Open study Of dental pulp stem cell Therapy in Humans): Study protocol for evaluating safety and feasibility of autologous human adult dental pulp stem cell therapy in patients with chronic disability after stroke.

    PubMed

    Nagpal, Anjali; Kremer, Karlea L; Hamilton-Bruce, Monica A; Kaidonis, Xenia; Milton, Austin G; Levi, Christopher; Shi, Songtao; Carey, Leeanne; Hillier, Susan; Rose, Miranda; Zacest, Andrew; Takhar, Parabjit; Koblar, Simon A

    2016-07-01

    Stroke represents a significant global disease burden. As of 2015, there is no chemical or biological therapy proven to actively enhance neurological recovery during the chronic phase post-stroke. Globally, cell-based therapy in stroke is at the stage of clinical translation and may improve neurological function through various mechanisms such as neural replacement, neuroprotection, angiogenesis, immuno-modulation, and neuroplasticity. Preclinical evidence in a rodent model of middle cerebral artery ischemic stroke as reported in four independent studies indicates improvement in neurobehavioral function with adult human dental pulp stem cell therapy. Human adult dental pulp stem cells present an exciting potential therapeutic option for improving post-stroke disability. TOOTH (The Open study Of dental pulp stem cell Therapy in Humans) will investigate the use of autologous stem cell therapy for stroke survivors with chronic disability, with the following objectives: (a) determine the maximum tolerable dose of autologous dental pulp stem cell therapy; (b) define that dental pulp stem cell therapy at the maximum tolerable dose is safe and feasible in chronic stroke; and (c) estimate the parameters of efficacy required to design a future Phase 2/3 clinical trial. TOOTH is a Phase 1, open-label, single-blinded clinical trial with a pragmatic design that comprises three stages: Stage 1 will involve the selection of 27 participants with middle cerebral artery ischemic stroke and the commencement of autologous dental pulp stem cell isolation, growth, and testing in sequential cohorts (n = 3). Stage 2 will involve the transplantation of dental pulp stem cell in each cohort of participants with an ascending dose and subsequent observation for a 6-month period for any dental pulp stem cell-related adverse events. Stage 3 will investigate the neurosurgical intervention of the maximum tolerable dose of autologous dental pulp stem cell followed by 9 weeks of intensive task-specific rehabilitation. Advanced magnetic resonance and positron emission tomography neuro-imaging, and clinical assessment will be employed to probe any change afforded by stem cell therapy in combination with rehabilitation. Nine participants will step-wise progress in Stage 2 to a dose of up to 10 million dental pulp stem cell, employing a cumulative 3 + 3 statistical design with low starting stem cell dose and subsequent dose escalation, assuming that an acceptable probability of dose-limiting complications is between 1 in 6 (17%) and 1 in 3 (33%) of patients. In Stage 3, another 18 participants will receive an intracranial injection with the maximum tolerable dose of dental pulp stem cell. The primary outcomes to be measured are safety and feasibility of intracranial administration of autologous human adult DPSC in patients with chronic stroke and determination of the maximum tolerable dose in human subjects. Secondary outcomes include estimation of the measures of effectiveness required to design a future Phase 2/3 clinical trial. © 2016 World Stroke Organization.

  2. Migratory potential of transplanted glial progenitors as critical factor for successful translation of glia replacement therapy: The gap between mice and men.

    PubMed

    Srivastava, Rohit K; Bulte, Jeff W M; Walczak, Piotr; Janowski, Miroslaw

    2018-05-01

    Neurological disorders are a major threat to public health. Stem cell-based regenerative medicine is now a promising experimental paradigm for its treatment, as shown in pre-clinical animal studies. Initial attempts have been on the replacement of neuronal cells only, but glial progenitors (GPs) are now becoming strong alternative cellular therapeutic candidates to replace oligodendrocytes and astrocytes as knowledge accumulates about their important emerging role in various disease processes. There are many examples of successful therapeutic outcomes for transplanted GPs in small animal models, but clinical translation has proved to be challenging due to the 1,000-fold larger volume of the human brain compared to mice. Human GPs transplanted into the mouse brain migrate extensively and can induce global cell replacement, but a similar extent of migration in the human brain would only allow for local rather than global cell replacement. We review here the mechanisms that govern cell migration, which could potentially be exploited to enhance the migratory properties of GPs through cell engineering pre-transplantation. We furthermore discuss the (dis)advantages of the various cell delivery routes that are available, with particular emphasis on intra-arterial injection as the most suitable route for achieving global cell distribution in the larger brain. Now that therapeutic success has proven to be feasible in small animal models, future efforts will need to be directed to enhance global cell delivery and migration to make bench-to-bedside translation a reality. © 2017 Wiley Periodicals, Inc.

  3. Engraftment and Differentiation of Embryonic Stem Cell–Derived Neural Progenitor Cells in the Cochlear Nerve Trunk: Growth of Processes into the Organ of Corti

    PubMed Central

    Corrales, C. Eduardo; Pan, Luying; Li, Huawei; Liberman, M. Charles; Heller, Stefan; Edge, Albert S.B.

    2007-01-01

    Hearing loss in mammals is irreversible because cochlear neurons and hair cells do not regenerate. To determine whether we could replace neurons lost to primary neuronal degeneration, we injected EYFP-expressing embryonic stem cell–derived mouse neural progenitor cells into the cochlear nerve trunk in immunosuppressed animals 1 week after destroying the cochlear nerve (spiral ganglion) cells while leaving hair cells intact by ouabain application to the round window at the base of the cochlea in gerbils. At 3 days post transplantation, small grafts were seen that expressed endogenous EYFP and could be immunolabeled for neuron-specific markers. Twelve days after transplantation, the grafts had neurons that extended processes from the nerve core toward the denervated organ of Corti. By 64–98 days, the grafts had sent out abundant processes that occupied a significant portion of the space formerly occupied by the cochlear nerve. The neurites grew in fasciculating bundles projecting through Rosenthal’s canal, the former site of spiral ganglion cells, into the osseous spiral lamina and ultimately into the organ of Corti, where they contacted hair cells. Neuronal counts showed a significant increase in neuronal processes near the sensory epithelium, compared to animals that were denervated without subsequent stem cell transplantation. The regeneration of these neurons shows that neurons differentiated from stem cells have the capacity to grow to a specific target in an animal model of neuronal degeneration. PMID:17013931

  4. In vitro study of stem cell communication via gap junctions for fibrocartilage regeneration at entheses.

    PubMed

    Nayak, Bibhukalyan Prasad; Goh, James Cho Hong; Toh, Siew Lok; Satpathy, Gyan Ranjan

    2010-03-01

    Entheses are fibrocartilaginous organs that bridge ligament with bone at their interface and add significant insertional strength. To replace a severely damaged ligament, a tissue-engineered graft preinstalled with interfacial fibrocartilage, which is being regenerated from stem cells, appears to be more promising than ligament-alone graft. Such a concept can be realized by a biomimetic approach of establishing a dynamic communication of stem cells with bone cells and/or ligament fibroblasts in vitro. The current study has two objectives. The first objective is to demonstrate functional coculture of bone marrow-derived stem cells (BMSCs) with mature bone cells/ligament fibroblasts as evidenced by gap-junctional communication in vitro. The second objective is to investigate the role of BMSCs in the regeneration of fibrocartilage within the coculture. Rabbit bone/ligament fibroblasts were dual-stained with DiI-Red and calcein (gap-junction permeable dye), and cocultured with unlabeled BMSCs at fixed ratio (1:10). The functional gap junction was demonstrated by the transfer of calcein from donor to recipient cells that was confirmed and quantified by flow cytometry. Type 2 collagen (cartilage extracellular matrix-specific protein) expressed by the mixed cell lines in the cocultures were estimated by real-time reverse transcription PCR and compared with that of the ligament-bone coculture (control). Significant transfer of calcein into BMSCs was observed and flow cytometry analyses showed a gradual increase in the percentage of BMSCs acquiring calcein with time. Cocultures that included BMSCs expressed significantly more type 2 collagen compared with the control. The current study, for the first time, reported the expression of gap-junctional communication of BMSCs with two adherent cell lines of musculoskeletal system in vitro and also confirmed that incorporation of stem cells augments fibrocartilage regeneration. The results open up a path to envisage a composite graft preinstalled with enthesial fibrocartilage using a stem cell-based coculture system.

  5. Fail-Safe Therapy by Gamma-Ray Irradiation Against Tumor Formation by Human-Induced Pluripotent Stem Cell-Derived Neural Progenitors.

    PubMed

    Katsukawa, Mitsuko; Nakajima, Yusuke; Fukumoto, Akiko; Doi, Daisuke; Takahashi, Jun

    2016-06-01

    Cell replacement therapy holds great promise for Parkinson's disease (PD), but residual undifferentiated cells and immature neural progenitors in the therapy may cause tumor formation. Although cell sorting could effectively exclude these proliferative cells, from the viewpoint of clinical application, there exists no adequate coping strategy in the case of their contamination. In this study, we analyzed a component of proliferative cells in the grafts of human-induced pluripotent stem cell-derived neural progenitors and investigated the effect of radiation therapy on tumor formation. In our differentiating protocol, analyses of neural progenitors (day 19) revealed that the proliferating cells expressed early neural markers (SOX1, PAX6) or a dopaminergic neuron progenitor marker (FOXA2). When grafted into the rat striatum, these immature neurons gradually became postmitotic in the brain, and the rosette structures disappeared at 14 weeks. However, at 4-8 weeks, the SOX1(+)PAX6(+) cells formed rosette structures in the grafts, suggesting their tumorigenic potential. Therefore, to develop a fail-safe therapy against tumor formation, we investigated the effect of radiation therapy. At 4 weeks posttransplantation, when KI67(+) cells comprised the highest ratio, radiation therapy with (137)Cs Gammacell Exactor for tumor-bearing immunodeficient rats showed a significant decrease in graft volume and percentage of SOX1(+)KI67(+) cells in the graft, thus demonstrating the preventive effect of gamma-ray irradiation against tumorigenicity. These results give us critical criteria for the safety of future cell replacement therapy for PD.

  6. Electrical and Mechanical Strategies to Enable Cardiac Repair and Regeneration

    PubMed Central

    Cao, Hung; Kang, Bong Jin; Lee, Chia-An; Shung, K. Kirk; Hsiai, Tzung K.

    2015-01-01

    Inadequate replacement of lost ventricular myocardium from myocardial infarction leads to heart failure. Investigating the regenerative capacity of mammalian hearts represents an emerging direction for tissue engineering and cell-based therapy. Recent advances in stem cells hold promise to restore cardiac functions. However, embryonic or induced pluripotent stem cell-derived cardiomyocytes lack functional phenotypes of the native myocardium, and transplanted tissues are not fully integrated for synchronized electrical and mechanical coupling with the host. In this context, this review highlights the mechanical and electrical strategies to promote cardiomyocyte maturation and integration, and to assess the functional phenotypes of regenerating myocardium. Simultaneous micro-electrocardiogram and high-frequency ultrasound techniques will also be introduced to assess electrical and mechanical coupling for small animal models of heart regeneration. PMID:25974948

  7. Platelet lysate supports the in vitro expansion of human periodontal ligament stem cells for cytotherapeutic use.

    PubMed

    Wu, Rui-Xin; Yu, Yang; Yin, Yuan; Zhang, Xi-Yu; Gao, Li-Na; Chen, Fa-Ming

    2017-08-01

    Human platelet lysate (PL) produced under optimal conditions of standardization and safety has been increasingly suggested as the future 'gold standard' supplement to replace fetal bovine serum (FBS) for the ex vivo propagation of mesenchymal stem cells for translational medicine and cell therapy applications. However, the multifaceted effects of PL on tissue-specific stem cells remain largely unexplored. In the present study, we investigated the stem cell behaviours of human periodontal ligament stem cells (PDLSCs) in media with or without PL. Our data indicate that human PL, either as an adjuvant for culture media or as a substitute for FBS, supports the proliferation and expansion of human PDLSCs derived from either 'young' or 'old' donors to the same extent as FBS, without interfering with their immunomodulatory capacities. Although PL appears to inhibit the in vitro differentiation of 'young' or 'old' PDLSCs, their decreased osteogenic potential may be restored to similar or higher levels compared with FBS-expanded cells. PL- and FBS-expanded PDLSCs exhibited a similar potential to form mineralized nodules and expressed similar levels of osteogenic genes. Our data indicate that large clinically relevant quantities of PDLSCs may be yielded by the use of human PL; however, further analysis of its precise composition and function will pave the way for determining optimized, defined culture conditions. In addition to the potential increase in patient safety, our findings highlight the need for further research to develop the potential of PL-expanded PDLSCs for clinical use. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  8. Changes in human bone marrow fat content associated with changes in hematopoietic stem cell numbers and cytokine levels with aging.

    PubMed

    Tuljapurkar, Sonal R; McGuire, Timothy R; Brusnahan, Susan K; Jackson, John D; Garvin, Kevin L; Kessinger, Margaret A; Lane, Judy T; O' Kane, Barbara J; Sharp, John G

    2011-11-01

    Hematological deficiencies increase with aging, including anemias, reduced responses to hematopoietic stress and myelodysplasias. This investigation tested the hypothesis that increased bone marrow (BM) fat content in humans with age was associated with decreased numbers of side population (SP) hematopoietic stem cells, and this decrease correlated with changes in cytokine levels. BM was obtained from the femoral head and trochanteric region of the femur removed at surgery for total hip replacement (N = 100 subjects). In addition, BM from cadavers (N = 36), with no evidence of hip disease, was evaluated for fat content. Whole trabecular marrow samples were ground in a sterile mortar and pestle, and cellularity and lipid content determined. Marrow cells were stained with Hoechst dye and SP profiles were acquired. Plasma levels of insulin-like growth factor (IGF)-1, stromal-derived factor (SDF)-1 and interleukin (IL)-6 were measured using ELISA. Fat content in the BM of human subjects and cadavers increased with age. The numbers of SP stem cells in BM as well as plasma IGF-1 and SDF-1 levels decreased in correlation with increased BM fat. IL-6 had no relationship to changes in marrow fat. These data suggest that increased BM fat may be associated with a decreased number of SP stem cells and IGF-1 and SDF-1 levels with aging. These data further raise a more general question as to the role of adipose cells in the regulation of tissue stem cells. © 2011 The Authors. Journal of Anatomy © 2011 Anatomical Society of Great Britain and Ireland.

  9. Mouse embryonic stem cell-derived cells reveal niches that support neuronal differentiation in the adult rat brain.

    PubMed

    Maya-Espinosa, Guadalupe; Collazo-Navarrete, Omar; Millán-Aldaco, Diana; Palomero-Rivero, Marcela; Guerrero-Flores, Gilda; Drucker-Colín, René; Covarrubias, Luis; Guerra-Crespo, Magdalena

    2015-02-01

    A neurogenic niche can be identified by the proliferation and differentiation of its naturally residing neural stem cells. However, it remains unclear whether "silent" neurogenic niches or regions suitable for neural differentiation, other than the areas of active neurogenesis, exist in the adult brain. Embryoid body (EB) cells derived from embryonic stem cells (ESCs) are endowed with a high potential to respond to specification and neuralization signals of the embryo. Hence, to identify microenvironments in the postnatal and adult rat brain with the capacity to support neuronal differentiation, we transplanted dissociated EB cells to conventional neurogenic and non-neurogenic regions. Our results show a neuronal differentiation pattern of EB cells that was dependent on the host region. Efficient neuronal differentiation of EB cells occurred within an adjacent region to the rostral migratory stream. EB cell differentiation was initially patchy and progressed toward an even distribution along the graft by 15-21 days post-transplantation, giving rise mostly to GABAergic neurons. EB cells in the striatum displayed a lower level of neuronal differentiation and derived into a significant number of astrocytes. Remarkably, when EB cells were transplanted to the striatum of adult rats after a local ischemic stroke, increased number of neuroblasts and neurons were observed. Unexpectedly, we determined that the adult substantia nigra pars compacta, considered a non-neurogenic area, harbors a robust neurogenic environment. Therefore, neurally uncommitted cells derived from ESCs can detect regions that support neuronal differentiation within the adult brain, a fundamental step for the development of stem cell-based replacement therapies. © 2014 AlphaMed Press.

  10. Cellular genetic therapy.

    PubMed

    Del Vecchio, F; Filareto, A; Spitalieri, P; Sangiuolo, F; Novelli, G

    2005-01-01

    Cellular genetic therapy is the ultimate frontier for those pathologies that are consequent to a specific nonfunctional cellular type. A viable cure for there kinds of diseases is the replacement of sick cells with healthy ones, which can be obtained from the same patient or a different donor. In fact, structures can be corrected and strengthened with the introduction of undifferentiated cells within specific target tissues, where they will specialize into the desired cellular types. Furthermore, consequent to the recent results obtained with the transdifferentiation experiments, a process that allows the in vitro differentiation of embryonic and adult stem cells, it has also became clear that many advantages may be obtained from the use of stem cells to produce drugs, vaccines, and therapeutic molecules. Since stem cells can sustain lineage potentials, the capacity for differentiation, and better tolerance for the introduction of exogenous genes, they are also considered as feasible therapeutic vehicles for gene therapy. In fact, it is strongly believed that the combination of cellular genetic and gene therapy approaches will definitely allow the development of new therapeutic strategies as well as the production of totipotent cell lines to be used as experimental models for the cure of genetic disorders.

  11. [Differentiation of human periodontal ligament stem cells into neuron-like cells in vitro].

    PubMed

    Zhen, Lei; Liu, Hong-Wei

    2009-02-01

    To isolate and purify the human periodontal ligament stem cells (PDLSC) and investigate the differentiation potentials of PDLSC into neuron-like cells in vitro. PDLSC were isolated and cultivated. PDLSC of passage 2 was plated at a density of 5 x 10(3) per mL. At 80% confluence, the PDLSC were preinduced for 24 hours, and were subsequently replaced with an inducing medium containing certain concentration of 13-mercaptoethanal (beta-ME). After 6 hours of induction, the results were evaluated by morphological observation, immunocytochemical staining for neuron specific enolase (NSE), neurofilament (NF) and glial fibrillary acid protein (GFAP) expression and RT-PCR for NSE, NF, GFAP mRNA. Meanwhile, the uninduced PDLSC were used as a negative control. PDLSC could be differentiate into cells with typical neuronal morphology. Immunohisto-chemistry and RT-PCR confirmed that the induced cells expressed NSE and NF, two marked enzymes of neuron cell. PDLSC can be induced into neuron-like cells in vitro. PDLSC have the capability of multilineage differentiations.

  12. Pancreatic islet cell therapy for type I diabetes: understanding the effects of glucose stimulation on islets in order to produce better islets for transplantation.

    PubMed

    Ren, Jiaqiang; Jin, Ping; Wang, Ena; Liu, Eric; Harlan, David M; Li, Xin; Stroncek, David F

    2007-01-03

    While insulin replacement remains the cornerstone treatment for type I diabetes mellitus (T1DM), the transplantation of pancreatic islets of Langerhans has the potential to become an important alternative. And yet, islet transplant therapy is limited by several factors, including far too few donor pancreases. Attempts to expand mature islets or to produce islets from stem cells are far from clinical application. The production and expansion of the insulin-producing cells within the islet (so called beta cells), or even creating cells that secrete insulin under appropriate physiological control, has proven difficult. The difficulty is explained, in part, because insulin synthesis and release is complex, unique, and not entirely characterized. Understanding beta-cell function at the molecular level will likely facilitate the development of techniques to manufacture beta-cells from stem cells. We will review islet transplantation, as well as the mechanisms underlying insulin transcription, translation and glucose stimulated insulin release.

  13. Pancreatic islet cell therapy for type I diabetes: understanding the effects of glucose stimulation on islets in order to produce better islets for transplantation

    PubMed Central

    Ren, Jiaqiang; Jin, Ping; Wang, Ena; Liu, Eric; Harlan, David M; Li, Xin; Stroncek, David F

    2007-01-01

    While insulin replacement remains the cornerstone treatment for type I diabetes mellitus (T1DM), the transplantation of pancreatic islets of Langerhans has the potential to become an important alternative. And yet, islet transplant therapy is limited by several factors, including far too few donor pancreases. Attempts to expand mature islets or to produce islets from stem cells are far from clinical application. The production and expansion of the insulin-producing cells within the islet (so called β cells), or even creating cells that secrete insulin under appropriate physiological control, has proven difficult. The difficulty is explained, in part, because insulin synthesis and release is complex, unique, and not entirely characterized. Understanding β-cell function at the molecular level will likely facilitate the development of techniques to manufacture β-cells from stem cells. We will review islet transplantation, as well as the mechanisms underlying insulin transcription, translation and glucose stimulated insulin release. PMID:17201925

  14. 3D Magnetic Stem Cell Aggregation and Bioreactor Maturation for Cartilage Regeneration.

    PubMed

    Van de Walle, Aurore; Wilhelm, Claire; Luciani, Nathalie

    2017-04-27

    Cartilage engineering remains a challenge due to the difficulties in creating an in vitro functional implant similar to the native tissue. An approach recently explored for the development of autologous replacements involves the differentiation of stem cells into chondrocytes. To initiate this chondrogenesis, a degree of compaction of the stem cells is required; hence, we demonstrated the feasibility of magnetically condensing cells, both within thick scaffolds and scaffold-free, using miniaturized magnetic field sources as cell attractors. This magnetic approach was also used to guide aggregate fusion and to build scaffold-free, organized, three-dimensional (3D) tissues several millimeters in size. In addition to having an enhanced size, the tissue formed by magnetic-driven fusion presented a significant increase in the expression of collagen II, and a similar trend was observed for aggrecan expression. As the native cartilage was subjected to forces that influenced its 3D structure, dynamic maturation was also performed. A bioreactor that provides mechanical stimuli was used to culture the magnetically seeded scaffolds over a 21-day period. Bioreactor maturation largely improved chondrogenesis into the cellularized scaffolds; the extracellular matrix obtained under these conditions was rich in collagen II and aggrecan. This work outlines the innovative potential of magnetic condensation of labeled stem cells and dynamic maturation in a bioreactor for improved chondrogenic differentiation, both scaffold-free and within polysaccharide scaffolds.

  15. Wound-Induced Polyploidization: Regulation by Hippo and JNK Signaling and Conservation in Mammals

    PubMed Central

    Losick, Vicki P.; Jun, Albert S.; Spradling, Allan C.

    2016-01-01

    Tissue integrity and homeostasis often rely on the proliferation of stem cells or differentiated cells to replace lost, aged, or damaged cells. Recently, we described an alternative source of cell replacement- the expansion of resident, non-dividing diploid cells by wound-induced polyploidization (WIP). Here we show that the magnitude of WIP is proportional to the extent of cell loss using a new semi-automated assay with single cell resolution. Hippo and JNK signaling regulate WIP; unexpectedly however, JNK signaling through AP-1 limits rather than stimulates the level of Yki activation and polyploidization in the Drosophila epidermis. We found that polyploidization also quantitatively compensates for cell loss in a mammalian tissue, mouse corneal endothelium, where increased cell death occurs with age in a mouse model of Fuchs Endothelial Corneal Dystrophy (FECD). Our results suggest that WIP is an evolutionarily conserved homeostatic mechanism that maintains the size and synthetic capacity of adult tissues. PMID:26958853

  16. Neuronal differentiation of stem cells isolated from adult muscle.

    PubMed

    Romero-Ramos, Marina; Vourc'h, Patrick; Young, Henry E; Lucas, Paul A; Wu, Young; Chivatakarn, Onanong; Zaman, Rumina; Dunkelman, Noushin; el-Kalay, Mohammad A; Chesselet, Marie-Françoise

    2002-09-15

    Lineage uncommitted pluripotent stem cells reside in the connective tissue of skeletal muscle. The present study was carried out with pluripotent stem cells (PPSCs) isolated from 6-month old rat muscle. Before differentiation, these cells were vimentin+, CD90+, CD45-, and varied in their expression of CD34. The PPSCs were expanded as non-adherent aggregates under similar conditions to those used to generate neurospheres from embryonic or neural stem cells. The PPSC-derived neurospheres were positive for nestin, an early marker present in neuronal precursors, and expressed the two alternative mRNA forms of the neuroectodermal marker Pax-6, as well as mRNA for Oct-4, a gene related to the pluripotentiality of stem cells. To confirm their neural potential, PPSC-derived neurospheres were plated on coated coverslips under varying conditions: Neurobasal medium with N2 or B27, and either NT3 or BDNF. After 4-6 days the cells expressed neuronal (Tuj1+, NF68), astrocytic (GFAP) and oligodendrocytic (MOSP+, MBP+) markers, both by immunocytochemistry and RT-PCR. In addition, PPSCs were cultured as monolayers under adherent conditions, exposed to growth factors and defined differentiating conditions for 5 hr, and subsequently kept for 2 days in a maturation medium. At this point they gave rise to a mixed population of early neural progenitors (Nestin+ or NG2+), immature and mature neurons (Tuj1+ and NF145+) and myelin producing oligodendrocytes (CNPase + and MOSP+). Our study shows that PPSCs present in adult muscle can overcome germ lineage restrictions and express the molecular characteristics of brain cells. Therefore, PPSCs isolated from adult muscle could provide a novel source for autologous cell replacement in neurodegenerative and demyelinating diseases. Copyright 2002 Wiley-Liss, Inc.

  17. Scaffolds in regenerative endodontics: A review

    PubMed Central

    Gathani, Kinjal M.; Raghavendra, Srinidhi Surya

    2016-01-01

    Root canal therapy has enabled us to save numerous teeth over the years. The most desired outcome of endodontic treatment would be when diseased or nonvital pulp is replaced with healthy pulp tissue that would revitalize the teeth through regenerative endodontics. ‘A search was conducted using the Pubmed and MEDLINE databases for articles with the criteria ‘Platelet rich plasma’, ‘Platelet rich fibrin’, ‘Stem cells’, ‘Natural and artificial scaffolds’ from 1982–2015’. Tissues are organized as three-dimensional structures, and appropriate scaffolding is necessary to provide a spatially correct position of cell location and regulate differentiation, proliferation, or metabolism of the stem cells. Extracellular matrix molecules control the differentiation of stem cells, and an appropriate scaffold might selectively bind and localize cells, contain growth factors, and undergo biodegradation over time. Different scaffolds facilitate the regeneration of different tissues. To ensure a successful regenerative procedure, it is essential to have a thorough and precise knowledge about the suitable scaffold for the required tissue. This article gives a review on the different scaffolds providing an insight into the new developmental approaches on the horizon. PMID:27857762

  18. Induced pluripotent stem cells as a cellular model for studying Down Syndrome

    PubMed Central

    Brigida, Anna Lisa; Siniscalco, Dario

    2016-01-01

    Down Syndrome (DS), or Trisomy 21 Syndrome, is one of the most common genetic diseases. It is a chromosomal abnormality caused by a duplication of chromosome 21. DS patients show the presence of a third copy (or a partial third copy) of chromosome 21 (trisomy), as result of meiotic errors. These patients suffer of many health problems, such as intellectual disability, congenital heart disease, duodenal stenosis, Alzheimer’s disease, leukemia, immune system deficiencies, muscle hypotonia and motor disorders. About one in 1000 babies born each year are affected by DS. Alterations in the dosage of genes located on chromosome 21 (also called HSA21) are responsible for the DS phenotype. However, the molecular pathogenic mechanisms of DS triggering are still not understood; newest evidences suggest the involvement of epigenetic mechanisms. For obvious ethical reasons, studies performed on DS patients, as well as on human trisomic tissues are limited. Some authors have proposed mouse models of this syndrome. However, not all the features of the syndrome are represented. Stem cells are considered the future of molecular and regenerative medicine. Several types of stem cells could provide a valid approach to offer a potential treatment for some untreatable human diseases. Stem cells also represent a valid system to develop new cell-based drugs and/or a model to study molecular disease pathways. Among stem cell types, patient-derived induced pluripotent stem (iPS) cells offer some advantages for cell and tissue replacement, engineering and studying: self-renewal capacity, pluripotency and ease of accessibility to donor tissues. These cells can be reprogrammed into completely different cellular types. They are derived from adult somatic cells via reprogramming with ectopic expression of four transcription factors (Oct3/4, Sox2, c-Myc and Klf4; or, Oct3/4, Sox2, Nanog, and Lin28). By reprogramming cells from DS patients, it is possible to obtain new tissue with the same genetic background, offering a valuable tool for studying this genetic disease and to design customized patient-specific stem cell therapies. PMID:28096629

  19. The synergistic effect of beta-boswellic acid and Nurr1 overexpression on dopaminergic programming of antioxidant glutathione peroxidase-1-expressing murine embryonic stem cells.

    PubMed

    Abasi, M; Massumi, M; Riazi, G; Amini, H

    2012-10-11

    Parkinson's disease (PD) is a neurodegenerative disorder in which the nigro-striatal dopaminergic (DAergic) neurons have been selectively lost. Due to side effects of levodopa, a dopamine precursor drug, recently cell replacement therapy for PD has been considered. Lack of sufficient amounts of, embryos and ethical problems regarding the use of dopamine-rich embryonic neural cells have limited the application of these cells for PD cell therapy. Therefore, many investigators have focused on using the pluripotent stem cells to generate DAergic neurons. This study is aimed first to establish a mouse embryonic stem (mES) cell line that can stably co-express Nurr1 (Nuclear receptor subfamily 4, group A, member 2) transcription factor in order to efficiently generate DAergic neurons, and glutathione peroxidase-1 (GPX-1) to protect the differentiated DAergic-like cells against oxidative stress. In addition to genetic engineering of ES cells, the effect of Beta-boswellic acid (BBA) on DAergic differentiation course of mES cells was sought in the present study. To that end, the feeder-independent CGR8 mouse embryonic stem cells were transduced by Nurr1- and GPX-1-harboring Lentiviruses and the generated Nurr1/GPX-1-expresssing ES clones were characterized and verified. Gene expression analyses demonstrated that BBA treatment and overexpression of Nurr1 has a synergistic effect on derivation of DAergic neurons from Nurr1/GPX-1-expressing ES cells. The differentiated cells could exclusively synthesize and secrete dopamine in response to stimuli. Overexpression of GPX-1 in genetically engineered Nurr1/GPX-1-ES cells increased the viability of these cells during their differentiation into CNS stem cells. In conclusion, the results demonstrated that Nurr1-overexpressing feeder-independent ES cells like the feeder-dependent ES cells, can be efficiently programmed into functional DAergic neurons and additional treatment of cells by BBA can even augment this efficiency. GPX-1 overexpression in Nurr1/GPX-1-ES cells increases the viability of differentiated CNS stem-like cells. The result of this study may have impact on future stem cell therapy of PD. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

  20. What is the role of biosimilar G-CSF agents in hematopoietic stem cell mobilization at present?

    PubMed

    Korkmaz, Serdal; Altuntas, Fevzi

    2017-12-01

    Mobilization of hematopoietic stem cells, which has largely replaced bone marrow harvesting as a source of hematopoietic stem cells, using recombinant agents such as filgrastim or lenograstim has become a standard procedure in both patients and healthy donors prior to peripheral blood stem cell collection for autologous and allogeneic stem cell transplantation. Published literature data suggest that mobilization with recombinant granulocyte-colony stimulating factor (G-CSF) is safe and mobilization outcomes are satisfactory. In recent years, besides G-CSF originators, biosimilar G-CSF agents have been approved by the regulatory agencies for the same indications. Current data showed that by using the biosimilar G-CSF, similar results regarding safety and efficacy of hematopoietic stem cell mobilization may be achieved compared to the originator G-CSF. Although the issues such as the similarity to a licenced biological medicine, differences in manufacturing processes, the potential to cause immunogenicity, extrapolation and interchangeability of these biosimilar products are still being discussed by the scientific area, however, more experience with these agents now exists in approved endications and there seems to be no reason to expect significant differences between biosimilar G-CSF and originator G-CSF regarding their efficacy and safety in both patients and healthy donors. Also, the significant cost savings of biosimilars in real life setting may enhance the use of these agents in the future. Nonetheless, the collection of long-term follow-up data is mandatory for both patients and healthy donors, and multicentre randomized clinical trials that directly compare biosimilar G-CSF with the originator G-CSF are needed in order to allow the transplant community to make informed decisions regarding the choice of G-CSF. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Cure for thalassemia major – from allogeneic hematopoietic stem cell transplantation to gene therapy

    PubMed Central

    Srivastava, Alok; Shaji, Ramachandran V.

    2017-01-01

    Allogeneic hematopoietic stem cell transplantation has been well established for several decades as gene replacement therapy for patients with thalassemia major, and now offers very high rates of cure for patients who have access to this therapy. Outcomes have improved tremendously over the last decade, even in high-risk patients. The limited data available suggests that the long-term outcome is also excellent, with a >90% survival rate, but for the best results, hematopoietic stem cell transplantation should be offered early, before any end organ damage occurs. However, access to this therapy is limited in more than half the patients by the lack of suitable donors. Inadequate hematopoietic stem cell transplantation services and the high cost of therapy are other reasons for this limited access, particularly in those parts of the world which have a high prevalence of this condition. As a result, fewer than 10% of eligible patients are actually able to avail of this therapy. Other options for curative therapies are therefore needed. Recently, gene correction of autologous hematopoietic stem cells has been successfully established using lentiviral vectors, and several clinical trials have been initiated. A gene editing approach to correct the β-globin mutation or disrupt the BCL11A gene to increase fetal hemoglobin production has also been reported, and is expected to be introduced in clinical trials soon. Curative possibilities for the major hemoglobin disorders are expanding. Providing access to these therapies around the world will remain a challenge. PMID:27909215

  2. ADAM10 Regulates Notch Function in Intestinal Stem Cells of Mice

    PubMed Central

    Tsai, Yu-Hwai; VanDussen, Kelli L.; Sawey, Eric T.; Wade, Alex W.; Kasper, Chelsea; Rakshit, Sabita; Bhatt, Riha G.; Stoeck, Alex; Maillard, Ivan; Crawford, Howard C.; Samuelson, Linda C.; Dempsey, Peter J.

    2014-01-01

    BACKGROUND & AIMS ADAM10 is a cell surface sheddase that regulates physiological processes including Notch signaling. ADAM10 is expressed in all intestinal epithelial cell types but the requirement for ADAM10 signaling in crypt homeostasis is not well defined. METHODS We analyzed intestinal tissues from mice with constitutive (Vil-Cre;Adam10f/f mice) and conditional (Vil-CreER;Adam10f/f and Lgr5-CreER;Adam10f/f mice) deletion of ADAM10. We performed cell lineage tracing experiments in mice that expressed a gain-of-function allele of Notch in the intestine (Rosa26NICD) or mice with intestine-specific disruption of Notch (Rosa26DN-MAML), to examine the effects of ADAM10 deletion on cell fate specification and intestinal stem cell maintenance. RESULTS Loss of ADAM10 from developing and adult intestine caused lethality associated with altered intestinal morphology, reduced progenitor cell proliferation, and increased secretory cell differentiation. ADAM10 deletion led to the replacement of intestinal cell progenitors with 2 distinct, post-mitotic, secretory cell lineages: intermediate-like (Paneth/goblet) and enteroendocrine cells. Based on analysis of Rosa26NICD and Rosa26DN-MAML mice, we determined that ADAM10 controls these cell fate decisions by regulating Notch signaling. Cell lineage tracing experiments showed that ADAM10 is required for survival of Lgr5+ crypt-based columnar cells. Our findings indicate that Notch-activated stem cells have a competitive advantage for occupation of the stem cell niche. CONCLUSIONS ADAM10 acts in a cell autonomous manner within the intestinal crypt compartment to regulate Notch signaling. This process is required for progenitor cell lineage specification and crypt-based columnar cell maintenance. PMID:25038433

  3. Fibrinogen Induces RUNX2 Activity and Osteogenic Development from Human Pluripotent Stem Cells

    PubMed Central

    Kidwai, Fahad; Edwards, Jessica; Zou, Li; Kaufman, Dan S.

    2016-01-01

    Pluripotent stem cells, both human embryonic stem cells (hESC) and induced pluripotent stem cells (iPSC), provide an important resource to produce specialized cells such as osteogenic cells for therapeutic applications such as repair or replacement of injured, diseased or damaged bone. hESCs and iPSCs can also be used to better define basic cellular and genetic mechanisms that regulate the earliest stages of human bone development. However, current strategies to mediate osteogenic differentiation of hESC and iPSC are typically limited by the use of xenogeneic components such as fetal bovine serum (FBS) that make defining specific agents that mediate human osteogenesis difficult. Runt-related transcription factor 2 (RUNX2) is a key regulator required for osteogenic differentiation. Here, we used a RUNX2-YFP reporter system to characterize the novel ability of fibrinogen to mediate human osteogenic development from hESC and iPSC in defined (serum-free) conditions. These studies demonstrate that fibrinogen mediates significant osteo-induction potential. Specifically, fibrinogen binds to the surface integrin (α9β1) to mediate RUNX2 gene expression through the SMAD1/5/8 signaling pathway. Additional studies characterize the fibrinogen-induced hESC/iPSC-derived osteogenic cells to demonstrate these osteogenic cells retain the capacity to express typical mature osteoblastic markers. Together, these studies define a novel fibrinogen-α9β1-SMAD1/5/8-RUNX2 signaling axis can efficiently induce osteogenic differentiation from hESCs and iPSCs. PMID:27331788

  4. Transplantation of neurons derived from human iPS cells cultured on collagen matrix into guinea-pig cochleae.

    PubMed

    Ishikawa, Masaaki; Ohnishi, Hiroe; Skerleva, Desislava; Sakamoto, Tatsunori; Yamamoto, Norio; Hotta, Akitsu; Ito, Juichi; Nakagawa, Takayuki

    2017-06-01

    The present study examined the efficacy of a neural induction method for human induced pluripotent stem (iPS) cells to eliminate undifferentiated cells and to determine the feasibility of transplanting neurally induced cells into guinea-pig cochleae for replacement of spiral ganglion neurons (SGNs). A stepwise method for differentiation of human iPS cells into neurons was used. First, a neural induction method was established on Matrigel-coated plates; characteristics of cell populations at each differentiation step were assessed. Second, neural stem cells were differentiated into neurons on a three-dimensional (3D) collagen matrix, using the same protocol of culture on Matrigel-coated plates; neuron subtypes in differentiated cells on a 3D collagen matrix were examined. Then, human iPS cell-derived neurons cultured on a 3D collagen matrix were transplanted into intact guinea-pig cochleae, followed by histological analysis. In vitro analyses revealed successful induction of neural stem cells from human iPS cells, with no retention of undifferentiated cells expressing OCT3/4. After the neural differentiation of neural stem cells, approximately 70% of cells expressed a neuronal marker, 90% of which were positive for vesicular glutamate transporter 1 (VGLUT1). The expression pattern of neuron subtypes in differentiated cells on a 3D collagen matrix was identical to that of the differentiated cells on Matrigel-coated plates. In addition, the survival of transplant-derived neurons was achieved when inflammatory responses were appropriately controlled. Our preparation method for human iPS cell-derived neurons efficiently eliminated undifferentiated cells and contributed to the settlement of transplant-derived neurons expressing VGLUT1 in guinea-pig cochleae. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  5. Induced pluripotent stem cell-based therapy for age-related macular degeneration.

    PubMed

    Bracha, Peter; Moore, Nicholas A; Ciulla, Thomas A

    2017-09-01

    In age-related macular degeneration (AMD), stem cells could possibly replace or regenerate disrupted pathologic retinal pigment epithelium (RPE), and produce supportive growth factors and cytokines such as brain-derived neurotrophic factor.  Induced pluripotent stem cells (iPSCs)-derived RPE was first subretinally transplanted in a neovascular AMD patient in 2014. Areas covered: Induced PSCs are derived from the introduction of transcription factors to adult cells under specific cell culture conditions, followed by differentiation into RPE cells. Induced PSC-derived RPE cells exhibit ion transport, membrane potential, polarized VEGF secretion and gene expression that is similar to native RPE. Despite having similar in vitro function, morphology, immunostaining and microscopic analysis, it remains to be seen if iPSC-derived RPE can replicate the myriad of in vivo functions, including immunomodulatory effects, of native RPE cells.  Historically, adjuvant RPE transplantation during CNV resections were technically difficult and complicated by immune rejection. Autologous iPSCs are hypothesized to reduce the risk of immune rejection, but their production is time-consuming and expensive.  Alternatively, allogenic transplantation using human leukocyte antigen (HLA)-matched iPSCs, similar to HLA-matched organ transplantation, is currently being investigated. Expert opinion: Challenges to successful transplantation with iPSCs include surgical technique, a pathologic subretinal microenvironment, possible immune rejection, and complications of immunosuppression.

  6. A Voltage-Sensitive Dye-Based Assay for the Identification of Differentiated Neurons Derived from Embryonic Neural Stem Cell Cultures

    PubMed Central

    Emirandetti, Amanda; Lewicka, Michalina; Hermanson, Ola; Fisahn, André

    2010-01-01

    Background Pluripotent and multipotent stem cells hold great therapeutical promise for the replacement of degenerated tissue in neurological diseases. To fulfill that promise we have to understand the mechanisms underlying the differentiation of multipotent cells into specific types of neurons. Embryonic stem cell (ESC) and embryonic neural stem cell (NSC) cultures provide a valuable tool to study the processes of neural differentiation, which can be assessed using immunohistochemistry, gene expression, Ca2+-imaging or electrophysiology. However, indirect methods such as protein and gene analysis cannot provide direct evidence of neuronal functionality. In contrast, direct methods such as electrophysiological techniques are well suited to produce direct evidence of neural functionality but are limited to the study of a few cells on a culture plate. Methodology/Principal Findings In this study we describe a novel method for the detection of action potential-capable neurons differentiated from embryonic NSC cultures using fast voltage-sensitive dyes (VSD). We found that the use of extracellularly applied VSD resulted in a more detailed labeling of cellular processes compared to calcium indicators. In addition, VSD changes in fluorescence translated precisely to action potential kinetics as assessed by the injection of simulated slow and fast sodium currents using the dynamic clamp technique. We further demonstrate the use of a finite element model of the NSC culture cover slip for optimizing electrical stimulation parameters. Conclusions/Significance Our method allows for a repeatable fast and accurate stimulation of neurons derived from stem cell cultures to assess their differentiation state, which is capable of monitoring large amounts of cells without harming the overall culture. PMID:21079795

  7. Self-Organization of Stem Cell Colonies and of Early Mammalian Embryos: Recent Experiments Shed New Light on the Role of Autonomy vs. External Instructions in Basic Body Plan Development

    PubMed Central

    Denker, Hans-Werner

    2016-01-01

    “Organoids”, i.e., complex structures that can develop when pluripotent or multipotent stem cells are maintained in three-dimensional cultures, have become a new area of interest in stem cell research. Hopes have grown that when focussing experimentally on the mechanisms behind this type of in vitro morphogenesis, research aiming at tissue and organ replacements can be boosted. Processes leading to the formation of organoids in vitro are now often addressed as self-organization, a term referring to the formation of complex tissue architecture in groups of cells without depending on specific instruction provided by other cells or tissues. The present article focuses on recent reports using the term self-organization in the context of studies on embryogenesis, specifically addressing pattern formation processes in human blastocysts attaching in vitro, or in colonies of pluripotent stem cells (“gastruloids”). These morphogenetic processes are of particular interest because, during development in vivo, they lead to basic body plan formation and individuation. Since improved methodologies like those employed by the cited authors became available, early embryonic pattern formation/self-organization appears to evolve now as a research topic of its own. This review discusses concepts concerning the involved mechanisms, focussing on autonomy of basic body plan development vs. dependence on external signals, as possibly provided by implantation in the uterus, and it addresses biological differences between an early mammalian embryo, e.g., a morula, and a cluster of pluripotent stem cells. It is concluded that, apart from being of considerable biological interest, the described type of research needs to be contemplated carefully with regard to ethical implications when performed with human cells. PMID:27792143

  8. Self-Organization of Stem Cell Colonies and of Early Mammalian Embryos: Recent Experiments Shed New Light on the Role of Autonomy vs. External Instructions in Basic Body Plan Development.

    PubMed

    Denker, Hans-Werner

    2016-10-25

    " Organoids ", i.e., complex structures that can develop when pluripotent or multipotent stem cells are maintained in three-dimensional cultures, have become a new area of interest in stem cell research. Hopes have grown that when focussing experimentally on the mechanisms behind this type of in vitro morphogenesis, research aiming at tissue and organ replacements can be boosted. Processes leading to the formation of organoids in vitro are now often addressed as self-organization , a term referring to the formation of complex tissue architecture in groups of cells without depending on specific instruction provided by other cells or tissues. The present article focuses on recent reports using the term self-organization in the context of studies on embryogenesis , specifically addressing pattern formation processes in human blastocysts attaching in vitro, or in colonies of pluripotent stem cells (" gastruloids "). These morphogenetic processes are of particular interest because, during development in vivo, they lead to basic body plan formation and individuation. Since improved methodologies like those employed by the cited authors became available, early embryonic pattern formation/self-organization appears to evolve now as a research topic of its own. This review discusses concepts concerning the involved mechanisms, focussing on autonomy of basic body plan development vs. dependence on external signals, as possibly provided by implantation in the uterus, and it addresses biological differences between an early mammalian embryo, e.g., a morula, and a cluster of pluripotent stem cells. It is concluded that, apart from being of considerable biological interest, the described type of research needs to be contemplated carefully with regard to ethical implications when performed with human cells.

  9. The regenerative medicine in oral and maxillofacial surgery: the most important innovations in the clinical application of mesenchymal stem cells.

    PubMed

    Tatullo, Marco; Marrelli, Massimo; Paduano, Francesco

    2015-01-01

    Regenerative medicine is an emerging field of biotechnology that combines various aspects of medicine, cell and molecular biology, materials science and bioengineering in order to regenerate, repair or replace tissues. The oral surgery and maxillofacial surgery have a role in the treatment of traumatic or degenerative diseases that lead to a tissue loss: frequently, to rehabilitate these minuses, you should use techniques that have been improved over time. Since 1990, we started with the use of growth factors and platelet concentrates in oral and maxillofacial surgery; in the following period we start to use biomaterials, as well as several type of scaffolds and autologous tissues. The frontier of regenerative medicine nowadays is represented by the mesenchymal stem cells (MSCs): overcoming the ethical problems thanks to the use of mesenchymal stem cells from adult patient, and with the increasingly sophisticated technology to support their manipulation, MSCs are undoubtedly the future of medicine regenerative and they are showing perspectives unimaginable just a few years ago. Most recent studies are aimed to tissues regeneration using MSCs taken from sites that are even more accessible and rich in stem cells: the oral cavity turned out to be an important source of MSCs with the advantage to be easily accessible to the surgeon, thus avoiding to increase the morbidity of the patient. The future is the regeneration of whole organs or biological systems consisting of many different tissues, starting from an initial stem cell line, perhaps using innovative scaffolds together with the nano-engineering of biological tissues.

  10. Barrett oesophagus: lessons on its origins from the lesion itself.

    PubMed

    McDonald, Stuart A C; Lavery, Danielle; Wright, Nicholas A; Jansen, Marnix

    2015-01-01

    Barrett oesophagus develops when the lower oesophageal squamous epithelium is replaced with columnar epithelium, which shows both intestinal and gastric differentiation. No consensus has been reached on the origin of Barrett oesophagus. Theories include a direct origin from the oesophageal-stratified squamous epithelium, or by proximal migration of the gastric cardiac epithelium with subsequent intestinalization. Variations of this theory suggest the origin is a distinctive cell at the squamocolumnar junction, the oesophageal gland ducts, or circulating bone-marrow-derived cells. Much of the supporting evidence comes from experimental models and not from studies of Barrett mucosa. In this Perspectives article, we look at the Barrett lesion itself: at its phenotype, its complexity, its clonal architecture and its stem cell organization. We conclude that Barrett glands are unique structures, but share many similarities with gastric glands undergoing the process of intestinal metaplasia. We conclude that current evidence most strongly supports an origin from stem cells in the cardia.

  11. Electrospun nanofibers: Work for medicine?

    NASA Astrophysics Data System (ADS)

    Liao, Susan; Chan, Casey K.; Ramakrishna, S.

    2010-03-01

    Attempts have been made to fabricate nanofibrous scaffolds to mimic the chemical composition and structural properties of the extracellular matrix (ECM) for tissue/organ replacement. Nanofiber scaffolds with various patterns have been successfully produced from synthetic and natural polymers through a relatively simple technique of electrospinning. The resulting patterns can mimic some of the diverse tissue-specific orientation and three-dimensional (3D) fibrous structures. Studies on cell-nanofiber interactions, including studies on stem cells, have revealed the importance of nanotopography on cell adhesion, proliferation and differentiation. Furthermore, clinical application of electrospun nanofibers including wound healing, tissue regeneration, drug delivery and stem cell therapy are highly feasible due to the ease and flexibility of fabrication of making nanofiber with this cost-effective method using electrospinning. In this review, we have highlighted the current state of the art and provided future perspectives on electrospun nanofiber in medical applications.

  12. Differences of isolated dental stem cells dependent on donor age and consequences for autologous tooth replacement.

    PubMed

    Kellner, Manuela; Steindorff, Marina M; Strempel, Jürgen F; Winkel, Andreas; Kühnel, Mark P; Stiesch, Meike

    2014-06-01

    Autologous therapy via stem cell-based tissue regeneration is an aim to rebuild natural teeth. One option is the use of adult stem cells from the dental pulp (DPSCs), which have been shown to differentiate into several types of tissue in vitro and in vivo, especially into tooth-like structures. DPSCs are mainly isolated from the dental pulp of third molars routinely extracted for orthodontic reasons. Due to the extraction of third molars at various phases of life, DPSCs are isolated at different developmental stages of the tooth. The present study addressed the question whether DPSCs from patients of different ages were similar in their growth characteristics with respect to the stage of tooth development. Therefore DPSCs from third molars of 12-30 year-old patients were extracted, and growth characteristics, e.g. doubling time and maximal cell division potential were analysed. In addition, pulp and hard dental material weight were recorded. Irrespective of the age of patients almost all isolated cells reached 40-60 generations with no correlation between maximal cell division potential and patient age. Cells from patients <22 years showed a significantly faster doubling time than the cells from patients ≥22 years. The age of patients at the time of stem cell isolation is not a crucial factor concerning maximal cell division potential, but does have an impact on the doubling time. However, differences in individuals regarding growth characteristics were more pronounced than age-dependent differences. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Original and regenerating lizard tail cartilage contain putative resident stem/progenitor cells.

    PubMed

    Alibardi, Lorenzo

    2015-11-01

    Regeneration of cartilaginous tissues is limited in mammals but it occurs with variable extension in lizards (reptiles), including in their vertebrae. The ability of lizard vertebrae to regenerate cartilaginous tissue that is later replaced with bone has been analyzed using tritiated thymidine autoradiography and 5BrdU immunocytochemistry after single pulse or prolonged-pulse and chase experiments. The massive cartilage regeneration that can restore broad vertebral regions and gives rise to a long cartilaginous tube in the regenerating tail, depends from the permanence of some chondrogenic cells within adult vertebrae. Few cells that retain tritiated thymidine or 5-bromodeoxy-uridine for over 35 days are mainly localized in the inter-vertebral cartilage and in sparse chondrogenic regions of the neural arch of the vertebrae, suggesting that they are putative resident stem/progenitor cells. The study supports previous hypothesis indicating that the massive regeneration of the cartilaginous tissue in damaged vertebrae and in the regenerating tail of lizards derive from resident stem cells mainly present in the cartilaginous areas of the vertebrae including in the perichondrium that are retained in adult lizards as growing centers for most of their lifetime. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Oxytocin and cardioprotection in diabetes and obesity.

    PubMed

    Jankowski, Marek; Broderick, Tom L; Gutkowska, Jolanta

    2016-06-07

    Oxytocin (OT) emerges as a drug for the treatment of diabetes and obesity. The entire OT system is synthesized in the rat and human heart. The direct myocardial infusion with OT into an ischemic or failing heart has the potential to elicit a variety of cardioprotective effects. OT treatment attenuates cardiomyocyte (CMs) death induced by ischemia-reperfusion by activating pro-survival pathways within injured CMs in vivo and in isolated cells. OT treatment reduces cardiac apoptosis, fibrosis, and hypertrophy. The OT/OT receptor (OTR) system is downregulated in the db/db mouse model of type 2 diabetes which develops genetic diabetic cardiomyopathy (DC) similar to human disease. We have shown that chronic OT treatment prevents the development of DC in the db/db mouse. In addition, OT stimulates glucose uptake in both cardiac stem cells and CMs, and increases cell resistance to diabetic conditions. OT may help replace lost CMs by stimulating the in situ differentiation of cardiac stem cells into functional mature CMs. Lastly, adult stem cells amenable for transplantation such as MSCs could be preconditioned with OT ex vivo and implanted into the injured heart to aid in tissue regeneration through direct differentiation, secretion of protective and cardiomyogenic factors and/or their fusion with injured CMs.

  15. Reprogramming of Sheep Fibroblasts into Pluripotency under a Drug-Inducible Expression of Mouse-Derived Defined Factors

    PubMed Central

    Li, Yang; Cang, Ming; Lee, Andrew Stephen; Zhang, Kehua; Liu, Dongjun

    2011-01-01

    Animal embryonic stem cells (ESCs) provide powerful tool for studies of early embryonic development, gene targeting, cloning, and regenerative medicine. However, the majority of attempts to establish ESC lines from large animals, especially ungulate mammals have failed. Recently, another type of pluripotent stem cells, known as induced pluripotent stem cells (iPSCs), have been successfully generated from mouse, human, monkey, rat and pig. In this study we show sheep fibroblasts can be reprogrammed to pluripotency by defined factors using a drug-inducible system. Sheep iPSCs derived in this fashion have a normal karyotype, exhibit morphological features similar to those of human ESCs and express AP, Oct4, Sox2, Nanog and the cell surface marker SSEA-4. Pluripotency of these cells was further confirmed by embryoid body (EB) and teratoma formation assays which generated derivatives of all three germ layers. Our results also show that the substitution of knockout serum replacement (KSR) with fetal bovine serum in culture improves the reprogramming efficiency of sheep iPSCs. Generation of sheep iPSCs places sheep on the front lines of large animal preclinical trials and experiments involving modification of animal genomes. PMID:21253598

  16. Vector-Free and Transgene-Free Human iPS Cells Differentiate into Functional Neurons and Enhance Functional Recovery after Ischemic Stroke in Mice

    PubMed Central

    Mohamad, Osama; Faulkner, Ben; Chen, Dongdong; Yu, Shan Ping; Wei, Ling

    2013-01-01

    Stroke is a leading cause of human death and disability in the adult population in the United States and around the world. While stroke treatment is limited, stem cell transplantation has emerged as a promising regenerative therapy to replace or repair damaged tissues and enhance functional recovery after stroke. Recently, the creation of induced pluripotent stem (iPS) cells through reprogramming of somatic cells has revolutionized cell therapy by providing an unlimited source of autologous cells for transplantation. In addition, the creation of vector-free and transgene-free human iPS (hiPS) cells provides a new generation of stem cells with a reduced risk of tumor formation that was associated with the random integration of viral vectors seen with previous techniques. However, the potential use of these cells in the treatment of ischemic stroke has not been explored. In the present investigation, we examined the neuronal differentiation of vector-free and transgene-free hiPS cells and the transplantation of hiPS cell-derived neural progenitor cells (hiPS-NPCs) in an ischemic stroke model in mice. Vector-free hiPS cells were maintained in feeder-free and serum-free conditions and differentiated into functional neurons in vitro using a newly developed differentiation protocol. Twenty eight days after transplantation in stroke mice, hiPS-NPCs showed mature neuronal markers in vivo. No tumor formation was seen up to 12 months after transplantation. Transplantation of hiPS-NPCs restored neurovascular coupling, increased trophic support and promoted behavioral recovery after stroke. These data suggest that using vector-free and transgene-free hiPS cells in stem cell therapy are safe and efficacious in enhancing recovery after focal ischemic stroke in mice. PMID:23717557

  17. Platelet-Rich Plasma Favors Proliferation of Canine Adipose-Derived Mesenchymal Stem Cells in Methacrylate-Endcapped Caprolactone Porous Scaffold Niches

    PubMed Central

    Rodríguez-Jiménez, Francisco Javier; Valdes-Sánchez, Teresa; Carrillo, José M.; Rubio, Mónica; Monleon-Prades, Manuel; García-Cruz, Dunia Mercedes; García, Montserrat; Cugat, Ramón; Moreno-Manzano, Victoria

    2012-01-01

    Osteoarticular pathologies very often require an implementation therapy to favor regeneration processes of bone, cartilage and/or tendons. Clinical approaches performed on osteoarticular complications in dogs constitute an ideal model for human clinical translational applications. The adipose-derived mesenchymal stem cells (ASCs) have already been used to accelerate and facilitate the regenerative process. ASCs can be maintained in vitro and they can be differentiated to osteocytes or chondrocytes offering a good tool for cell replacement therapies in human and veterinary medicine. Although ACSs can be easily obtained from adipose tissue, the amplification process is usually performed by a time consuming process of successive passages. In this work, we use canine ASCs obtained by using a Bioreactor device under GMP cell culture conditions that produces a minimum of 30 million cells within 2 weeks. This method provides a rapid and aseptic method for production of sufficient stem cells with potential further use in clinical applications. We show that plasma rich in growth factors (PRGF) treatment positively contributes to viability and proliferation of canine ASCs into caprolactone 2-(methacryloyloxy) ethyl ester (CLMA) scaffolds. This biomaterial does not need additional modifications for cASCs attachment and proliferation. Here we propose a framework based on a combination of approaches that may contribute to increase the therapeutical capability of stem cells by the use of PRGF and compatible biomaterials for bone and connective tissue regeneration. PMID:24955632

  18. Neural stem cell heterogeneity through time and space in the ventricular-subventricular zone.

    PubMed

    Rushing, Gabrielle; Ihrie, Rebecca A

    2016-08-01

    The origin and classification of neural stem cells (NSCs) has been a subject of intense investigation for the past two decades. Efforts to categorize NSCs based on their location, function and expression have established that these cells are a heterogeneous pool in both the embryonic and adult brain. The discovery and additional characterization of adult NSCs has introduced the possibility of using these cells as a source for neuronal and glial replacement following injury or disease. To understand how one could manipulate NSC developmental programs for therapeutic use, additional work is needed to elucidate how NSCs are programmed and how signals during development are interpreted to determine cell fate. This review describes the identification, classification and characterization of NSCs within the large neurogenic niche of the ventricular-subventricular zone (V-SVZ). A literature search was conducted using Pubmed including the keywords "ventricular-subventricular zone," "neural stem cell," "heterogeneity," "identity" and/or "single cell" to find relevant manuscripts to include within the review. A special focus was placed on more recent findings using single-cell level analyses on neural stem cells within their niche(s). This review discusses over 20 research articles detailing findings on V-SVZ NSC heterogeneity, over 25 articles describing fate determinants of NSCs, and focuses on 8 recent publications using distinct single-cell analyses of neural stem cells including flow cytometry and RNA-seq. Additionally, over 60 manuscripts highlighting the markers expressed on cells within the NSC lineage are included in a chart divided by cell type. Investigation of NSC heterogeneity and fate decisions is ongoing. Thus far, much research has been conducted in mice however, findings in human and other mammalian species are also discussed here. Implications of NSC heterogeneity established in the embryo for the properties of NSCs in the adult brain are explored, including how these cells may be redirected after injury or genetic manipulation.

  19. Innate (inherent) control of brain infection, brain inflammation and brain repair: the role of microglia, astrocytes, "protective" glial stem cells and stromal ependymal cells.

    PubMed

    Hauwel, Mathieu; Furon, Emeline; Canova, Cecile; Griffiths, Mark; Neal, Jim; Gasque, Philippe

    2005-04-01

    In invertebrates and primitive vertebrates, the brain contains large numbers of "professional" macrophages associated with neurones, ependymal tanycytes and radial glia to promote robust regenerative capacity. In higher vertebrates, hematogenous cells are largely excluded from the brain, and innate immune molecules and receptors produced by the resident "amateur" macrophages (microglia, astrocytes and ependymal cells) control pathogen infiltration and clearance of toxic cell debris. However, there is minimal capacity for regeneration. The transfer of function from hematogenous cells to macroglia and microglia is associated with the sophistication of a yet poorly-characterized neurone-glia network. This evolutionary pattern may have been necessary to reduce the risk of autoimmune attack while preserving the neuronal web but the ability to repair central nervous system damage may have been sacrificed in the process. We herein argue that it may be possible to re-educate and stimulate the resident phagocytes to promote clearance of pathogens (e.g., Prion), toxic cell debris (e.g., amyloid fibrils and myelin) and apoptotic cells. Moreover, as part of this greater division of labour between cell types in vertebrate brains, it may be possible to harness the newly described properties of glial stem cells in neuronal protection (revitalization) rather than replacement, and to control brain inflammation. We will also highlight the emerging roles of stromal ependymal cells in controlling stem cell production and migration into areas of brain damage. Understanding the mechanisms involved in the nurturing of damaged neurons by protective glial stem cells with the safe clearance of cell debris could lead to remedial strategies for chronic brain diseases.

  20. A simple and cost-effective method for isolation and expansion of human fetal pancreas derived mesenchymal stem cells.

    PubMed

    Larijani, Bagher; Arjmand, Babak; Ahmadbeigi, Naser; Falahzadeh, Khadijeh; Soleimani, Masoud; Sayahpour, Forough Azam; Aghayan, Hamid Reza

    2015-11-01

    Previous studies have suggested mesenchymal stem cells (MSCs) as a suitable source for cell replacement therapy in diabetes. MSCs have successfully isolated from different adult and fetal tissues, including the pancreas. In vitro studies have shown that human fetal pancreatic stem cells could be extensively expanded and differentiated into islet-like structures. Here, we introduce a simple and cost-effective method for the generation of MSCs from the human fetal pancreas (FPMSCs). To isolate FPMSCs, pancreata from four aborted fetuses (second trimester) were processed with short collagenase digestion. The resulting tissue fragments were transferred to a basic media (DMEM+15%FBS) without adding any growth factor. After 10 to14 days, fibroblast-like cells were harvested and passaged six times for further evaluations. Flow cytometry analysis and three-lineage differentiation capacity have demonstrated that these cells have MSC-like properties. We also continuously passaged samples of FPMSCs and found no evidence for chromosomal instability and morphological changes until 10th subculture. Moreover, our cell culture protocol can be easily modified and translated into a GMP-compliant one. The results of current study demonstrated that our simple and inexpensive method could yield a pure population of FPMSCs that might be suitable for transplantation.

  1. Genetic recombination pathways and their application for genome modification of human embryonic stem cells.

    PubMed

    Nieminen, Mikko; Tuuri, Timo; Savilahti, Harri

    2010-10-01

    Human embryonic stem cells are pluripotent cells derived from early human embryo and retain a potential to differentiate into all adult cell types. They provide vast opportunities in cell replacement therapies and are expected to become significant tools in drug discovery as well as in the studies of cellular and developmental functions of human genes. The progress in applying different types of DNA recombination reactions for genome modification in a variety of eukaryotic cell types has provided means to utilize recombination-based strategies also in human embryonic stem cells. Homologous recombination-based methods, particularly those utilizing extended homologous regions and those employing zinc finger nucleases to boost genomic integration, have shown their usefulness in efficient genome modification. Site-specific recombination systems are potent genome modifiers, and they can be used to integrate DNA into loci that contain an appropriate recombination signal sequence, either naturally occurring or suitably pre-engineered. Non-homologous recombination can be used to generate random integrations in genomes relatively effortlessly, albeit with a moderate efficiency and precision. DNA transposition-based strategies offer substantially more efficient random strategies and provide means to generate single-copy insertions, thus potentiating the generation of genome-wide insertion libraries applicable in genetic screens. 2010 Elsevier Inc. All rights reserved.

  2. IAP-Based Cell Sorting Results in Homogeneous Transplantable Dopaminergic Precursor Cells Derived from Human Pluripotent Stem Cells.

    PubMed

    Lehnen, Daniela; Barral, Serena; Cardoso, Tiago; Grealish, Shane; Heuer, Andreas; Smiyakin, Andrej; Kirkeby, Agnete; Kollet, Jutta; Cremer, Harold; Parmar, Malin; Bosio, Andreas; Knöbel, Sebastian

    2017-10-10

    Human pluripotent stem cell (hPSC)-derived mesencephalic dopaminergic (mesDA) neurons can relieve motor deficits in animal models of Parkinson's disease (PD). Clinical translation of differentiation protocols requires standardization of production procedures, and surface-marker-based cell sorting is considered instrumental for reproducible generation of defined cell products. Here, we demonstrate that integrin-associated protein (IAP) is a cell surface marker suitable for enrichment of hPSC-derived mesDA progenitor cells. Immunomagnetically sorted IAP + mesDA progenitors showed increased expression of ventral midbrain floor plate markers, lacked expression of pluripotency markers, and differentiated into mature dopaminergic (DA) neurons in vitro. Intrastriatal transplantation of IAP + cells sorted at day 16 of differentiation in a rat model of PD resulted in functional recovery. Grafts from sorted IAP + mesDA progenitors were more homogeneous in size and DA neuron density. Thus, we suggest IAP-based sorting for reproducible prospective enrichment of mesDA progenitor cells in clinical cell replacement strategies. Copyright © 2017 Miltenyi Biotec GmbH. Published by Elsevier Inc. All rights reserved.

  3. Transplantation of enteric nervous system stem cells rescues nitric oxide synthase deficient mouse colon

    PubMed Central

    McCann, Conor J.; Cooper, Julie E.; Natarajan, Dipa; Jevans, Benjamin; Burnett, Laura E.; Burns, Alan J.; Thapar, Nikhil

    2017-01-01

    Enteric nervous system neuropathy causes a wide range of severe gut motility disorders. Cell replacement of lost neurons using enteric neural stem cells (ENSC) is a possible therapy for these life-limiting disorders. Here we show rescue of gut motility after ENSC transplantation in a mouse model of human enteric neuropathy, the neuronal nitric oxide synthase (nNOS−/−) deficient mouse model, which displays slow transit in the colon. We further show that transplantation of ENSC into the colon rescues impaired colonic motility with formation of extensive networks of transplanted cells, including the development of nNOS+ neurons and subsequent restoration of nitrergic responses. Moreover, post-transplantation non-cell-autonomous mechanisms restore the numbers of interstitial cells of Cajal that are reduced in the nNOS−/− colon. These results provide the first direct evidence that ENSC transplantation can modulate the enteric neuromuscular syncytium to restore function, at the organ level, in a dysmotile gastrointestinal disease model. PMID:28671186

  4. Genetically Engineered Islets and Alternative Sources of Insulin-Producing Cells for Treating Autoimmune Diabetes: Quo Vadis?

    PubMed Central

    Chou, Feng-Cheng; Huang, Shing-Hwa; Sytwu, Huey-Kang

    2012-01-01

    Islet transplantation is a promising therapy for patients with type 1 diabetes that can provide moment-to-moment metabolic control of glucose and allow them to achieve insulin independence. However, two major problems need to be overcome: (1) detrimental immune responses, including inflammation induced by the islet isolation/transplantation procedure, recurrence autoimmunity, and allorejection, can cause graft loss and (2) inadequate numbers of organ donors. Several gene therapy approaches and pharmaceutical treatments have been demonstrated to prolong the survival of pancreatic islet grafts in animal models; however, the clinical applications need to be investigated further. In addition, for an alternative source of pancreatic β-cell replacement therapy, the ex vivo generation of insulin-secreting cells from diverse origins of stem/progenitor cells has become an attractive option in regenerative medicine. This paper focuses on the genetic manipulation of islets during transplantation therapy and summarizes current strategies to obtain functional insulin-secreting cells from stem/progenitor cells. PMID:22690214

  5. Induced Pluripotent Stem Cell-Derived Red Blood Cells and Platelet Concentrates: From Bench to Bedside.

    PubMed

    Focosi, Daniele; Amabile, Giovanni

    2017-12-27

    Red blood cells and platelets are anucleate blood components indispensable for oxygen delivery and hemostasis, respectively. Derivation of these blood elements from induced pluripotent stem (iPS) cells has the potential to develop blood donor-independent and genetic manipulation-prone products to complement or replace current transfusion banking, also minimizing the risk of alloimmunization. While the production of erythrocytes from iPS cells has challenges to overcome, such as differentiation into adult-type phenotype that functions properly after transfusion, platelet products are qualitatively and quantitatively approaching a clinically-applicable level owing to advances in expandable megakaryocyte (MK) lines, platelet-producing bioreactors, and novel reagents. Guidelines that assure the quality of iPS cells-derived blood products for clinical application represent a novel challenge for regulatory agencies. Considering the minimal risk of tumorigenicity and the expected significant demand of such products, ex vivo production of iPS-derived blood components can pave the way for iPS translation into the clinic.

  6. Sika Deer Antler Collagen Type I-Accelerated Osteogenesis in Bone Marrow Mesenchymal Stem Cells via the Smad Pathway

    PubMed Central

    Li, Na; Zhang, Min; Drummen, Gregor P. C.; Zhao, Yu; Tan, Yin Fen; Luo, Su; Qu, Xiao Bo

    2016-01-01

    Deer antler preparations have been used to strengthen bones for centuries. It is particularly rich in collagen type I. This study aimed to unravel part of the purported bioremedial effect of Sika deer antler collagen type I (SDA-Col I) on bone marrow mesenchymal stem cells. The results suggest that SDA-Col I might be used to promote and regulate osteoblast proliferation and differentiation. SDA-Col I might potentially provide the basis for novel therapeutic strategies in the treatment of bone injury and/or in scaffolds for bone replacement strategies. Finally, isolation of SDA-Col I from deer antler represents a renewable, green, and uncomplicated way to obtain a biomedically valuable therapeutic. PMID:27066099

  7. A low-cost, high-quality new drug discovery process using patient-derived induced pluripotent stem cells.

    PubMed

    Giri, Shibashish; Bader, Augustinus

    2015-01-01

    Knockout, knock-in and conditional mutant gene-targeted mice are routinely used for disease modeling in the drug discovery process, but the human response is often difficult to predict from these models. It is believed that patient-derived induced pluripotent stem cells (iPSCs) could replace millions of animals currently sacrificed in preclinical testing and provide a route to new safer pharmaceutical products. In this review, we discuss the use of IPSCs in the drug discovery process. We highlight how they can be used to assess the toxicity and clinical efficacy of drug candidates before the latter are moved into costly and lengthy preclinical and clinical trials. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Effect of Antibiotics against Mycoplasma sp. on Human Embryonic Stem Cells Undifferentiated Status, Pluripotency, Cell Viability and Growth

    PubMed Central

    Romorini, Leonardo; Riva, Diego Ariel; Blüguermann, Carolina; Videla Richardson, Guillermo Agustin; Scassa, Maria Elida; Sevlever, Gustavo Emilio; Miriuka, Santiago Gabriel

    2013-01-01

    Human embryonic stem cells (hESCs) are self-renewing pluripotent cells that can differentiate into specialized cells and hold great promise as models for human development and disease studies, cell-replacement therapies, drug discovery and in vitro cytotoxicity tests. The culture and differentiation of these cells are both complex and expensive, so it is essential to extreme aseptic conditions. hESCs are susceptible to Mycoplasma sp. infection, which is hard to detect and alters stem cell-associated properties. The purpose of this work was to evaluate the efficacy and cytotoxic effect of PlasmocinTM and ciprofloxacin (specific antibiotics used for Mycoplasma sp. eradication) on hESCs. Mycoplasma sp. infected HUES-5 884 (H5 884, stable hESCs H5-brachyury promoter-GFP line) cells were effectively cured with a 14 days PlasmocinTM 25 µg/ml treatment (curative treatment) while maintaining stemness characteristic features. Furthermore, cured H5 884 cells exhibit the same karyotype as the parental H5 line and expressed GFP, through up-regulation of brachyury promoter, at day 4 of differentiation onset. Moreover, H5 cells treated with ciprofloxacin 10 µg/ml for 14 days (mimic of curative treatment) and H5 and WA09 (H9) hESCs treated with PlasmocinTM 5 µg/ml (prophylactic treatment) for 5 passages retained hESCs features, as judged by the expression of stemness-related genes (TRA1-60, TRA1-81, SSEA-4, Oct-4, Nanog) at mRNA and protein levels. In addition, the presence of specific markers of the three germ layers (brachyury, Nkx2.5 and cTnT: mesoderm; AFP: endoderm; nestin and Pax-6: ectoderm) was verified in in vitro differentiated antibiotic-treated hESCs. In conclusion, we found that PlasmocinTM and ciprofloxacin do not affect hESCs stemness and pluripotency nor cell viability. However, curative treatments slightly diminished cell growth rate. This cytotoxic effect was reversible as cells regained normal growth rate upon antibiotic withdrawal. PMID:23936178

  9. Combination of nitric oxide therapy, anti-oxidative therapy, low level laser therapy, plasma rich platelet therapy and stem cell therapy as a novel therapeutic application to manage the pain and treat many clinical conditions

    NASA Astrophysics Data System (ADS)

    Halasa, Salaheldin; Dickinson, Eva

    2014-02-01

    From hypertension to diabetes, cancer to HIV, stroke to memory loss and learning disorders to septic shock, male impotence to tuberculosis, there is probably no pathological condition where nitric oxide does not play an important role. Nitric oxide is an analgesic, immune-modulator, vasodilator, anti-apoptotic, growth modulator, angiogenetic, anti-thrombotic, anti-inflammatory and neuro-modulator. Because of the above actions of nitric oxide, many clinical conditions associated with abnormal Nitric oxide (NO) production and bioavailability. Our novel therapeutic approach is to restore the homeostasis of nitric oxide and replace the lost cells by combining nitric oxide therapy, anti-oxidative therapy, low level laser therapy, plasma rich platelet therapy and stem cell therapy.

  10. Engineering kidney cells: reprogramming and directed differentiation to renal tissues.

    PubMed

    Kaminski, Michael M; Tosic, Jelena; Pichler, Roman; Arnold, Sebastian J; Lienkamp, Soeren S

    2017-07-01

    Growing knowledge of how cell identity is determined at the molecular level has enabled the generation of diverse tissue types, including renal cells from pluripotent or somatic cells. Recently, several in vitro protocols involving either directed differentiation or transcription-factor-based reprogramming to kidney cells have been established. Embryonic stem cells or induced pluripotent stem cells can be guided towards a kidney fate by exposing them to combinations of growth factors or small molecules. Here, renal development is recapitulated in vitro resulting in kidney cells or organoids that show striking similarities to mammalian embryonic nephrons. In addition, culture conditions are also defined that allow the expansion of renal progenitor cells in vitro. Another route towards the generation of kidney cells is direct reprogramming. Key transcription factors are used to directly impose renal cell identity on somatic cells, thus circumventing the pluripotent stage. This complementary approach to stem-cell-based differentiation has been demonstrated to generate renal tubule cells and nephron progenitors. In-vitro-generated renal cells offer new opportunities for modelling inherited and acquired renal diseases on a patient-specific genetic background. These cells represent a potential source for developing novel models for kidney diseases, drug screening and nephrotoxicity testing and might represent the first steps towards kidney cell replacement therapies. In this review, we summarize current approaches for the generation of renal cells in vitro and discuss the advantages of each approach and their potential applications.

  11. Human TSCM cell dynamics in vivo are compatible with long-lived immunological memory and stemness.

    PubMed

    Del Amo, Pedro Costa; Beneytez, Julio Lahoz; Boelen, Lies; Ahmed, Raya; Miners, Kelly L; Zhang, Yan; Roger, Laureline; Jones, Rhiannon E; Marraco, Silvia A Fuertes; Speiser, Daniel E; Baird, Duncan M; Price, David A; Ladell, Kristin; Macallan, Derek; Asquith, Becca

    2018-06-22

    Adaptive immunity relies on the generation and maintenance of memory T cells to provide protection against repeated antigen exposure. It has been hypothesised that a self-renewing population of T cells, named stem cell-like memory T (TSCM) cells, are responsible for maintaining memory. However, it is not clear if the dynamics of TSCM cells in vivo are compatible with this hypothesis. To address this issue, we investigated the dynamics of TSCM cells under physiological conditions in humans in vivo using a multidisciplinary approach that combines mathematical modelling, stable isotope labelling, telomere length analysis, and cross-sectional data from vaccine recipients. We show that, unexpectedly, the average longevity of a TSCM clone is very short (half-life < 1 year, degree of self-renewal = 430 days): far too short to constitute a stem cell population. However, we also find that the TSCM population is comprised of at least 2 kinetically distinct subpopulations that turn over at different rates. Whilst one subpopulation is rapidly replaced (half-life = 5 months) and explains the rapid average turnover of the bulk TSCM population, the half-life of the other TSCM subpopulation is approximately 9 years, consistent with the longevity of the recall response. We also show that this latter population exhibited a high degree of self-renewal, with a cell residing without dying or differentiating for 15% of our lifetime. Finally, although small, the population was not subject to excessive stochasticity. We conclude that the majority of TSCM cells are not stem cell-like but that there is a subpopulation of TSCM cells whose dynamics are compatible with their putative role in the maintenance of T cell memory.

  12. Advanced therapies for the treatment of hemophilia: future perspectives.

    PubMed

    Liras, Antonio; Segovia, Cristina; Gabán, Aline S

    2012-12-13

    Monogenic diseases are ideal candidates for treatment by the emerging advanced therapies, which are capable of correcting alterations in protein expression that result from genetic mutation. In hemophilia A and B such alterations affect the activity of coagulation factors VIII and IX, respectively, and are responsible for the development of the disease. Advanced therapies may involve the replacement of a deficient gene by a healthy gene so that it generates a certain functional, structural or transport protein (gene therapy); the incorporation of a full array of healthy genes and proteins through perfusion or transplantation of healthy cells (cell therapy); or tissue transplantation and formation of healthy organs (tissue engineering). For their part, induced pluripotent stem cells have recently been shown to also play a significant role in the fields of cell therapy and tissue engineering. Hemophilia is optimally suited for advanced therapies owing to the fact that, as a monogenic condition, it does not require very high expression levels of a coagulation factor to reach moderate disease status. As a result, significant progress has been possible with respect to these kinds of strategies, especially in the fields of gene therapy (by using viral and non-viral vectors) and cell therapy (by means of several types of target cells). Thus, although still considered a rare disorder, hemophilia is now recognized as a condition amenable to gene therapy, which can be administered in the form of lentiviral and adeno-associated vectors applied to adult stem cells, autologous fibroblasts, platelets and hematopoietic stem cells; by means of non-viral vectors; or through the repair of mutations by chimeric oligonucleotides. In hemophilia, cell therapy approaches have been based mainly on transplantation of healthy cells (adult stem cells or induced pluripotent cell-derived progenitor cells) in order to restore alterations in coagulation factor expression.

  13. Pancreatic islet-like clusters from bone marrow mesenchymal stem cells of human first-trimester abortus can cure streptozocin-induced mouse diabetes.

    PubMed

    Zhang, Yihua; Shen, Wenzheng; Hua, Jinlian; Lei, Anmin; Lv, Changrong; Wang, Huayan; Yang, Chunrong; Gao, Zhimin; Dou, Zhongying

    2010-12-01

    Bone marrow mesenchymal stem cells (BMSCs) have been reported to possess low immunogenicity and cause immunosuppression of recipients when allografted. They can differentiate into insulin-producing cells and may be a valuable source for islet formation. However, the extremely low differentiating rate of adult BMSCs toward insulin-producing cells and the insufficient insulin secretion of the differentiated BMSCs in vitro prevent their clinical use in diabetes treatment. Little is known about the potential of cell replacement therapy with human BMSCs. Previously, we isolated and identified human first-trimester fetal BMSCs (hfBMSCs). Under a novel four-step induction procedure established in this study, the hfBMSCs effectively differentiated into functional pancreatic islet-like cell clusters that contained 62 ± 14% insulin-producing cells, expressed a broad gene profile related to pancreatic islet β-cell development, and released high levels of insulin (2.245 ± 0.222 pmol/100 clusters per 30 min) and C-peptide (2.200 ± 0.468 pmol/100 clusters per 30 min) in response to 25 mmol/L glucose stimulus in vitro. The pancreatic islet-like cell clusters normalized the blood glucose level of diabetic model mice for at least 9 weeks when xenografted; blood glucose levels in these mice rose abnormally again when the grafts were removed. Examination of the grafts indicated that the transplanted cells survived in recipients and produced human insulin and C-peptide in situ. These results demonstrate that hfBMSCs derived from a human first-trimester abortus can differentiate into pancreatic islet-like cell clusters following an established four-step induction. The insulin-producing clusters present advantages in cell replacement therapy of type 1 diabetic model mice.

  14. 3D Bioprinted Artificial Trachea with Epithelial Cells and Chondrogenic-Differentiated Bone Marrow-Derived Mesenchymal Stem Cells.

    PubMed

    Bae, Sang-Woo; Lee, Kang-Woog; Park, Jae-Hyun; Lee, JunHee; Jung, Cho-Rok; Yu, JunJie; Kim, Hwi-Yool; Kim, Dae-Hyun

    2018-05-31

    Tracheal resection has limited applicability. Although various tracheal replacement strategies were performed using artificial prosthesis, synthetic stents and tissue transplantation, the best method in tracheal reconstruction remains to be identified. Recent advances in tissue engineering enabled 3D bioprinting using various biocompatible materials including living cells, thereby making the product clinically applicable. Moreover, clinical interest in mesenchymal stem cell has dramatically increased. Here, rabbit bone marrow-derived mesenchymal stem cells (bMSC) and rabbit respiratory epithelial cells were cultured. The chondrogenic differentiation level of bMSC cultured in regular media (MSC) and that in chondrogenic media (d-MSC) were compared. Dual cell-containing artificial trachea were manufactured using a 3D bioprinting method with epithelial cells and undifferentiated bMSC (MSC group, n = 6) or with epithelial cells and chondrogenic-differentiated bMSC (d-MSC group, n = 6). d-MSC showed a relatively higher level of glycosaminoglycan (GAG) accumulation and chondrogenic marker gene expression than MSC in vitro. Neo-epithelialization and neo-vascularization were observed in all groups in vivo but neo-cartilage formation was only noted in d-MSC. The epithelial cells in the 3D bioprinted artificial trachea were effective in respiratory epithelium regeneration. Chondrogenic-differentiated bMSC had more neo-cartilage formation potential in a short period. Nevertheless, the cartilage formation was observed only in a localized area.

  15. An Embryonic and Induced Pluripotent Stem Cell Model for Ovarian Granulosa Cell Development and Steroidogenesis.

    PubMed

    Lipskind, Shane; Lindsey, Jennifer S; Gerami-Naini, Behzad; Eaton, Jennifer L; O'Connell, Daniel; Kiezun, Adam; Ho, Joshua W K; Ng, Nicholas; Parasar, Parveen; Ng, Michelle; Nickerson, Michael; Demirci, Utkan; Maas, Richard; Anchan, Raymond M

    2018-05-01

    Embryoid bodies (EBs) can serve as a system for evaluating pluripotency, cellular differentiation, and tissue morphogenesis. In this study, we use EBs derived from mouse embryonic stem cells (mESCs) and human amniocyte-derived induced pluripotent stem cells (hAdiPSCs) as a model for ovarian granulosa cell (GC) development and steroidogenic cell commitment. We demonstrated that spontaneously differentiated murine EBs (mEBs) and human EBs (hEBs) displayed ovarian GC markers, such as aromatase (CYP19A1), FOXL2, AMHR2, FSHR, and GJA1. Comparative microarray analysis identified both shared and unique gene expression between mEBs and the maturing mouse ovary. Gene sets related to gonadogenesis, lipid metabolism, and ovarian development were significantly overrepresented in EBs. Of the 29 genes, 15 that were differentially regulated in steroidogenic mEBs displayed temporal expression changes between embryonic, postnatal, and mature ovarian tissues by polymerase chain reaction. Importantly, both mEBs and hEBs were capable of gonadotropin-responsive estradiol (E2) synthesis in vitro (217-759 pg/mL). Live fluorescence-activated cell sorting-sorted AMHR2 + granulosa-like cells from mEBs continued to produce E2 after purification (15.3 pg/mL) and secreted significantly more E2 than AMHR2 - cells (8.6 pg/mL, P < .05). We conclude that spontaneously differentiated EBs of both mESC and hAdiPSC origin can serve as a biologically relevant model for ovarian GC differentiation and steroidogenic cell commitment. These cells should be further investigated for therapeutic uses, such as stem cell-based hormone replacement therapy and in vitro maturation of oocytes.

  16. Clinical efficacy of gene-modified stem cells in adenosine deaminase-deficient immunodeficiency.

    PubMed

    Shaw, Kit L; Garabedian, Elizabeth; Mishra, Suparna; Barman, Provaboti; Davila, Alejandra; Carbonaro, Denise; Shupien, Sally; Silvin, Christopher; Geiger, Sabine; Nowicki, Barbara; Smogorzewska, E Monika; Brown, Berkley; Wang, Xiaoyan; de Oliveira, Satiro; Choi, Yeong; Ikeda, Alan; Terrazas, Dayna; Fu, Pei-Yu; Yu, Allen; Fernandez, Beatriz Campo; Cooper, Aaron R; Engel, Barbara; Podsakoff, Greg; Balamurugan, Arumugam; Anderson, Stacie; Muul, Linda; Jagadeesh, G Jayashree; Kapoor, Neena; Tse, John; Moore, Theodore B; Purdy, Ken; Rishi, Radha; Mohan, Kathey; Skoda-Smith, Suzanne; Buchbinder, David; Abraham, Roshini S; Scharenberg, Andrew; Yang, Otto O; Cornetta, Kenneth; Gjertson, David; Hershfield, Michael; Sokolic, Rob; Candotti, Fabio; Kohn, Donald B

    2017-05-01

    Autologous hematopoietic stem cell transplantation (HSCT) of gene-modified cells is an alternative to enzyme replacement therapy (ERT) and allogeneic HSCT that has shown clinical benefit for adenosine deaminase-deficient (ADA-deficient) SCID when combined with reduced intensity conditioning (RIC) and ERT cessation. Clinical safety and therapeutic efficacy were evaluated in a phase II study. Ten subjects with confirmed ADA-deficient SCID and no available matched sibling or family donor were enrolled between 2009 and 2012 and received transplantation with autologous hematopoietic CD34+ cells that were modified with the human ADA cDNA (MND-ADA) γ-retroviral vector after conditioning with busulfan (90 mg/m2) and ERT cessation. Subjects were followed from 33 to 84 months at the time of data analysis. Safety of the procedure was assessed by recording the number of adverse events. Efficacy was assessed by measuring engraftment of gene-modified hematopoietic stem/progenitor cells, ADA gene expression, and immune reconstitution. With the exception of the oldest subject (15 years old at enrollment), all subjects remained off ERT with normalized peripheral blood mononuclear cell (PBMC) ADA activity, improved lymphocyte numbers, and normal proliferative responses to mitogens. Three of nine subjects were able to discontinue intravenous immunoglobulin replacement therapy. The MND-ADA vector was persistently detected in PBMCs (vector copy number [VCN] = 0.1-2.6) and granulocytes (VCN = 0.01-0.3) through the most recent visits at the time of this writing. No patient has developed a leukoproliferative disorder or other vector-related clinical complication since transplant. These results demonstrate clinical therapeutic efficacy from gene therapy for ADA-deficient SCID, with an excellent clinical safety profile. ClinicalTrials.gov NCT00794508. Food and Drug Administration Office of Orphan Product Development award, RO1 FD003005; NHLBI awards, PO1 HL73104 and Z01 HG000122; UCLA Clinical and Translational Science Institute awards, UL1RR033176 and UL1TR000124.

  17. Clinical efficacy of gene-modified stem cells in adenosine deaminase–deficient immunodeficiency

    PubMed Central

    Shaw, Kit L.; Garabedian, Elizabeth; Mishra, Suparna; Barman, Provaboti; Davila, Alejandra; Carbonaro, Denise; Shupien, Sally; Silvin, Christopher; Geiger, Sabine; Nowicki, Barbara; Smogorzewska, E. Monika; Brown, Berkley; Wang, Xiaoyan; de Oliveira, Satiro; Choi, Yeong; Ikeda, Alan; Terrazas, Dayna; Fu, Pei-Yu; Yu, Allen; Fernandez, Beatriz Campo; Cooper, Aaron R.; Engel, Barbara; Podsakoff, Greg; Balamurugan, Arumugam; Anderson, Stacie; Muul, Linda; Jagadeesh, G. Jayashree; Kapoor, Neena; Tse, John; Moore, Theodore B.; Purdy, Ken; Rishi, Radha; Mohan, Kathey; Skoda-Smith, Suzanne; Buchbinder, David; Abraham, Roshini S.; Scharenberg, Andrew; Yang, Otto O.; Cornetta, Kenneth; Gjertson, David; Hershfield, Michael; Sokolic, Rob; Candotti, Fabio

    2017-01-01

    BACKGROUND. Autologous hematopoietic stem cell transplantation (HSCT) of gene-modified cells is an alternative to enzyme replacement therapy (ERT) and allogeneic HSCT that has shown clinical benefit for adenosine deaminase–deficient (ADA-deficient) SCID when combined with reduced intensity conditioning (RIC) and ERT cessation. Clinical safety and therapeutic efficacy were evaluated in a phase II study. METHODS. Ten subjects with confirmed ADA-deficient SCID and no available matched sibling or family donor were enrolled between 2009 and 2012 and received transplantation with autologous hematopoietic CD34+ cells that were modified with the human ADA cDNA (MND-ADA) γ-retroviral vector after conditioning with busulfan (90 mg/m2) and ERT cessation. Subjects were followed from 33 to 84 months at the time of data analysis. Safety of the procedure was assessed by recording the number of adverse events. Efficacy was assessed by measuring engraftment of gene-modified hematopoietic stem/progenitor cells, ADA gene expression, and immune reconstitution. RESULTS. With the exception of the oldest subject (15 years old at enrollment), all subjects remained off ERT with normalized peripheral blood mononuclear cell (PBMC) ADA activity, improved lymphocyte numbers, and normal proliferative responses to mitogens. Three of nine subjects were able to discontinue intravenous immunoglobulin replacement therapy. The MND-ADA vector was persistently detected in PBMCs (vector copy number [VCN] = 0.1–2.6) and granulocytes (VCN = 0.01–0.3) through the most recent visits at the time of this writing. No patient has developed a leukoproliferative disorder or other vector-related clinical complication since transplant. CONCLUSION. These results demonstrate clinical therapeutic efficacy from gene therapy for ADA-deficient SCID, with an excellent clinical safety profile. TRIAL REGISTRATION. ClinicalTrials.gov NCT00794508. FUNDING. Food and Drug Administration Office of Orphan Product Development award, RO1 FD003005; NHLBI awards, PO1 HL73104 and Z01 HG000122; UCLA Clinical and Translational Science Institute awards, UL1RR033176 and UL1TR000124. PMID:28346229

  18. Autologous serum improves bone formation in a primary stable silica-embedded nanohydroxyapatite bone substitute in combination with mesenchymal stem cells and rhBMP-2 in the sheep model

    PubMed Central

    Boos, Anja M; Weigand, Annika; Deschler, Gloria; Gerber, Thomas; Arkudas, Andreas; Kneser, Ulrich; Horch, Raymund E; Beier, Justus P

    2014-01-01

    New therapeutic strategies are required for critical size bone defects, because the gold standard of transplanting autologous bone from an unharmed area of the body often leads to several severe side effects and disadvantages for the patient. For years, tissue engineering approaches have been seeking a stable, axially vascularized transplantable bone replacement suitable for transplantation into the recipient bed with pre-existing insufficient conditions. For this reason, the arteriovenous loop model was developed and various bone substitutes have been vascularized. However, it has not been possible thus far to engineer a primary stable and axially vascularized transplantable bone substitute. For that purpose, a primary stable silica-embedded nanohydroxyapatite (HA) bone substitute in combination with blood, bone marrow, expanded, or directly retransplanted mesenchymal stem cells, recombinant human bone morphogenetic protein 2 (rhBMP-2), and different carrier materials (fibrin, cell culture medium, autologous serum) was tested subcutaneously for 4 or 12 weeks in the sheep model. Autologous serum lead to an early matrix change during degradation of the bone substitute and formation of new bone tissue. The best results were achieved in the group combining mesenchymal stem cells expanded with 60 μg/mL rhBMP-2 in autologous serum. Better ingrowth of fibrovascular tissue could be detected in the autologous serum group compared with the control (fibrin). Osteoclastic activity indicating an active bone remodeling process was observed after 4 weeks, particularly in the group with autologous serum and after 12 weeks in every experimental group. This study clearly demonstrates the positive effects of autologous serum in combination with mesenchymal stem cells and rhBMP-2 on bone formation in a primary stable silica-embedded nano-HA bone grafting material in the sheep model. In further experiments, the results will be transferred to the sheep arteriovenous loop model in order to engineer an axially vascularized primary stable bone replacement in clinically relevant size for free transplantation. PMID:25429218

  19. c-MYC independent nuclear reprogramming favors cardiogenic potential of induced pluripotent stem cells

    PubMed Central

    Martinez-Fernandez, Almudena; Nelson, Timothy J.; Ikeda, Yasuhiro; Terzic, Andre

    2010-01-01

    Induced pluripotent stem cell (iPS) technology has launched a new platform in regenerative medicine aimed at deriving unlimited replacement tissue from autologous sources through somatic cell reprogramming using stemness factor sets. In this way, authentic cardiomyocytes have been obtained from iPS and recently demonstrated in proof-of-principle studies to repair infarcted heart. Optimizing the cardiogenic potential of iPS progeny would ensure a maximized yield of bioengineered cardiac tissue. Here, we reprogrammed fibroblasts in the presence or absence of c-MYC to determine if the acquired cardiogenicity is sensitive to the method of nuclear reprogramming. Using lentiviral constructs that expressed stemness factors SOX2, OCT4, and KLF4 with or without c-MYC, iPS clones generated through fibroblast reprogramming demonstrated indistinguishable characteristics for 5 days of differentiation with similar cell morphology, growth rates, and chimeric embryo integration. However, 4-factor c-MYC dependent nuclear reprogramming produced iPS progeny that consistently prolonged the expression of pluripotent Oct-4 and Fgf4 genes and repressed cardiac differentiation. In contrast, 3-factor c-MYC-less iPS clones efficiently up-regulated pre-cardiac (CXCR4, Flk-1, and Mesp1/2) and cardiac (Nkx2.5, Mef2c, and Myocardin) gene expression patterns. In fact, 3-factor iPS progeny demonstrated early and robust cardiogenesis during in vitro differentiation with consistent beating activity, sarcomere maturation, and rhythmical intracellular calcium dynamics. Thus, nuclear reprogramming independent of c-MYC enhances production of pluripotent stem cells with innate cardiogenic potential. PMID:20221419

  20. Regeneration of Corneal Epithelium With Dental Pulp Stem Cells Using a Contact Lens Delivery System.

    PubMed

    Kushnerev, Evgeny; Shawcross, Susan G; Sothirachagan, Shankari; Carley, Fiona; Brahma, Arun; Yates, Julian M; Hillarby, M Chantal

    2016-10-01

    The corneal epithelium is sloughed off surface of the eye by the action of blinking and is continually replaced by division and maturation of the limbal stem cells (LSCs). In the case of injury or disease, LSCs can be lost or damaged to a point at which the corneal epithelial layer is no longer maintained. leading to LSC deficiencies (LSCDs). When this occurs, the opaque conjunctiva overgrows the anterior surface of the eye, leading to vision impairment or loss. Dental pulp stem cells (DPSCs) are promising candidates as autologous LSC substitutes. In this study, contact lenses (CLs) are used as a novel medical device to deliver DPSCs onto corneal surface to enhance corneal epithelium regeneration. Dental pulp stem cells labeled with green fluorescent Qtracker 525 were seeded onto the pretreated CLs, allowed to adhere, then delivered to debrided human corneas. Expression of KRT3, 12, 13, and 19 was investigated by immunostaining, then standard and confocal microscopy. Dental pulp stem cells were successfully isolated, labeled, and delivered to the corneal surface using CLs. Following removal of CLs, confocal microscopy showed that the DPSCs had migrated onto the cornea. Coexpression of KRT12 and green fluorescent Qtracker 525 confirmed that the DPSCs had transdifferentiated into corneal epithelial progenitors. Delimitation of KRT 19 and green fluorescence provides evidence that Qtracker 525-labeled DPSCs establish a barrier to the invasion of the cornea by conjunctiva. In this study we show that DPSCs, delivered using CLs, can be used to enhance repair and regeneration of the human corneal epithelium.

  1. Inhibition of the Activin Receptor Type-2B Pathway Restores Regenerative Capacity in Satellite Cell-Depleted Skeletal Muscle.

    PubMed

    Formicola, Luigi; Pannérec, Alice; Correra, Rosa Maria; Gayraud-Morel, Barbara; Ollitrault, David; Besson, Vanessa; Tajbakhsh, Shahragim; Lachey, Jennifer; Seehra, Jasbir S; Marazzi, Giovanna; Sassoon, David A

    2018-01-01

    Degenerative myopathies typically display a decline in satellite cells coupled with a replacement of muscle fibers by fat and fibrosis. During this pathological remodeling, satellite cells are present at lower numbers and do not display a proper regenerative function. Whether a decline in satellite cells directly contributes to disease progression or is a secondary result is unknown. In order to dissect these processes, we used a genetic model to reduce the satellite cell population by ~70-80% which leads to a nearly complete loss of regenerative potential. We observe that while no overt tissue damage is observed following satellite cell depletion, muscle fibers atrophy accompanied by changes in the stem cell niche cellular composition. Treatment of these mice with an Activin receptor type-2B (AcvR2B) pathway blocker reverses muscle fiber atrophy as expected, but also restores regenerative potential of the remaining satellite cells. These findings demonstrate that in addition to controlling fiber size, the AcvR2B pathway acts to regulate the muscle stem cell niche providing a more favorable environment for muscle regeneration.

  2. CRISPR/Cas9 system and its applications in human hematopoietic cells.

    PubMed

    Hu, Xiaotang

    2016-11-01

    Since 2012, the CRISPR-Cas9 system has been quickly and successfully tested in a broad range of organisms and cells including hematopoietic cells. The application of CRISPR-Cas9 in human hematopoietic cells mainly involves the genes responsible for HIV infection, β-thalassemia and sickle cell disease (SCD). The successful disruption of CCR5 and CXCR4 genes in T cells by CRISPR-Cas9 promotes the prospect of the technology in the functional cure of HIV. More recently, eliminating CCR5 and CXCR4 in induced pluripotent stem cells (iPSCs) derived from patients and targeting the HIV genome have been successfully carried out in several laboratories. The outcome from these approaches bring us closer to the goal of eradicating HIV infection. For hemoglobinopathies the ability to produce iPSC-derived from patients with the correction of hemoglobin (HBB) mutations by CRISPR-Cas9 has been tested in a number of laboratories. These corrected iPSCs also show the potential to differentiate into mature erythrocytes expressing high-level and normal HBB. In light of the initial success of CRESPR-Cas9 in target mutated gene(s) in the iPSCs, a combination of genomic editing and autogenetic stem cell transplantation would be the best strategy for root treatment of the diseases, which could replace traditional allogeneic stem cell transplantation. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. A fully defined and scalable 3D culture system for human pluripotent stem cell expansion and differentiation

    NASA Astrophysics Data System (ADS)

    Lei, Yuguo; Schaffer, David V.

    2013-12-01

    Human pluripotent stem cells (hPSCs), including human embryonic stem cells and induced pluripotent stem cells, are promising for numerous biomedical applications, such as cell replacement therapies, tissue and whole-organ engineering, and high-throughput pharmacology and toxicology screening. Each of these applications requires large numbers of cells of high quality; however, the scalable expansion and differentiation of hPSCs, especially for clinical utilization, remains a challenge. We report a simple, defined, efficient, scalable, and good manufacturing practice-compatible 3D culture system for hPSC expansion and differentiation. It employs a thermoresponsive hydrogel that combines easy manipulation and completely defined conditions, free of any human- or animal-derived factors, and entailing only recombinant protein factors. Under an optimized protocol, the 3D system enables long-term, serial expansion of multiple hPSCs lines with a high expansion rate (∼20-fold per 5-d passage, for a 1072-fold expansion over 280 d), yield (∼2.0 × 107 cells per mL of hydrogel), and purity (∼95% Oct4+), even with single-cell inoculation, all of which offer considerable advantages relative to current approaches. Moreover, the system enabled 3D directed differentiation of hPSCs into multiple lineages, including dopaminergic neuron progenitors with a yield of ∼8 × 107 dopaminergic progenitors per mL of hydrogel and ∼80-fold expansion by the end of a 15-d derivation. This versatile system may be useful at numerous scales, from basic biological investigation to clinical development.

  4. PCL/PVA nanofibrous scaffold improve insulin-producing cells generation from human induced pluripotent stem cells.

    PubMed

    Abazari, Mohammad Foad; Soleimanifar, Fatemeh; Aleagha, Maryam Nouri; Torabinejad, Sepehr; Nasiri, Navid; Khamisipour, Gholamreza; Mahabadi, Javad Amini; Mahboudi, Hossein; Enderami, Seyed Ehsan; Saburi, Ehsan; Hashemi, Javad; Kehtari, Mousa

    2018-05-31

    Pancreatic differentiation of stem cells will aid treatment of patients with type I diabetes mellitus (T1DM). Synthetic biopolymers utilization provided extracellular matrix (ECM) and desired attributes in vitro to enhance conditions for stem cells proliferation, attachment and differentiation. A mixture of polycaprolactone and polyvinyl alcohol (PCL/PVA)-based scaffold, could establish an in vitro three-dimensional (3D) culture model. The objective of this study was investigation of the human induced pluripotent stem cells (hiPSCs) differentiation capacity to insulin-producing cells (IPCs) in 3D culture were compared with conventional culture (2D) groups evaluated at the mRNA and protein levels by quantitative PCR and immunofluorescence assay, respectively. The functionality of differentiated IPCs was assessed by C-peptide and insulin release in response to glucose stimulation test. Real-Time PCR results showed that iPSCs-IPCs expressed pancreas-specific transcription factors (Insulin, Pdx1, Glucagon, Glut2 and Ngn3). The expressions of these transcription factors in PCL/PVA scaffold were higher than 2D groups. In addition to IPCs specific markers were detected by immunochemistry. These cells in both groups secreted insulin and C-peptide in a glucose challenge test by ELISA showing in vitro maturation. The results of current study demonstrated that enhanced differentiation of IPCs from hiPSCs could be result of PCL/PVA nanofibrous scaffolds. In conclusion, this research could provide a new approach to beta-like cells replacement therapies and pancreatic tissue engineering for T1DM in the future. Copyright © 2017. Published by Elsevier B.V.

  5. Neural stem cells for disease modeling and evaluation of therapeutics for infantile (CLN1/PPT1) and late infantile (CLN2/TPP1) neuronal ceroid lipofuscinoses.

    PubMed

    Sima, Ni; Li, Rong; Huang, Wei; Xu, Miao; Beers, Jeanette; Zou, Jizhong; Titus, Steven; Ottinger, Elizabeth A; Marugan, Juan J; Xie, Xing; Zheng, Wei

    2018-04-10

    Infantile and late infantile neuronal ceroid lipofuscinoses (NCLs) are lysosomal storage diseases affecting the central nervous system (CNS). The infantile NCL (INCL) is caused by mutations in the PPT1 gene and late-infantile NCL (LINCL) is due to mutations in the TPP1 gene. Deficiency in PPT1 or TPP1 enzyme function results in lysosomal accumulation of pathological lipofuscin-like material in the patient cells. There is currently no small-molecular drug treatment for NCLs. We have generated induced pluripotent stem cells (iPSC) from three patient dermal fibroblast lines and further differentiated them into neural stem cells (NSCs). Using these new disease models, we evaluated the effect of δ-tocopherol (DT) and hydroxypropyl-β-cyclodextrin (HPBCD) with the enzyme replacement therapy as the control. Treatment with the relevant recombinant enzyme or DT significantly ameliorated the lipid accumulation and lysosomal enlargement in the disease cells. A combination therapy of δ-tocopherol and HPBCD further improved the effect compared to that of either drug used as a single therapy. The results demonstrate that these patient iPSC derived NCL NSCs are valid cell- based disease models with characteristic disease phenotypes that can be used for study of disease pathophysiology and drug development.

  6. Induced pluripotent stem cell-derived cardiomyocytes for cardiovascular disease modeling and drug screening.

    PubMed

    Sharma, Arun; Wu, Joseph C; Wu, Sean M

    2013-12-24

    Human induced pluripotent stem cells (hiPSCs) have emerged as a novel tool for drug discovery and therapy in cardiovascular medicine. hiPSCs are functionally similar to human embryonic stem cells (hESCs) and can be derived autologously without the ethical challenges associated with hESCs. Given the limited regenerative capacity of the human heart following myocardial injury, cardiomyocytes derived from hiPSCs (hiPSC-CMs) have garnered significant attention from basic and translational scientists as a promising cell source for replacement therapy. However, ongoing issues such as cell immaturity, scale of production, inter-line variability, and cell purity will need to be resolved before human clinical trials can begin. Meanwhile, the use of hiPSCs to explore cellular mechanisms of cardiovascular diseases in vitro has proven to be extremely valuable. For example, hiPSC-CMs have been shown to recapitulate disease phenotypes from patients with monogenic cardiovascular disorders. Furthermore, patient-derived hiPSC-CMs are now providing new insights regarding drug efficacy and toxicity. This review will highlight recent advances in utilizing hiPSC-CMs for cardiac disease modeling in vitro and as a platform for drug validation. The advantages and disadvantages of using hiPSC-CMs for drug screening purposes will be explored as well.

  7. Cell transplantation in the damaged adult brain.

    PubMed

    Jaber, M; Benoit-Marand, M; Prestoz, L; Gaillard, A

    2013-11-01

    Parkinson's disease (PD) is the most common movement disorder in Europe, affecting more than two million people between 50 and 70 years of age. The current therapeutic approaches are of symptomatic nature and fail to halt the progressive neurodegenerative course of the disease. The development of innovative and complementary approaches to promote cellular repair may pave the way for disease-modifying therapies which may lead to less suffering for the patients and their families and finally to more cost-effective therapies. To date, cell replacement trials in PD aiming at replacing lost dopamine neurons were mainly focused on placing the transplanted cells within the target site, the striatum, and not within the lesioned site, the substantia nigra (SN). This was based on the misconception that the adult brain constitutes a non-permissive barrier not allowing the outgrowth of long distance axons originating from transplanted embryonic neurons. A growing body of evidence is challenging this concept and proposing instead to place the graft within its ontogenic site. This has been performed in several lesional animal models for various traumatic or neurodegenerative pathologies of the brain. For instance, transplanted neurons within the lesioned motor cortex were shown to be able to send distant and appropriate projections to target areas including the spinal cord. Similarly, in an animal model of PD, mesencephalic embryonic cells transplanted within the lesioned SN send massive projections to the striatum and, to a lesser extent, the frontal cortex and the nucleus accumbens. This has lead to the proposal that homotopic transplantation may be an alternative in cell-based therapies as transplanted neurons can integrate within the host brain, send projections to target areas, restore the damaged circuitry, increase neurotransmitter levels and ameliorate behavior. We will discuss also the potential of replacing embryonic neuronal cells by stem cell derived neurons as the use of embryonic cells is not without an ethical and logistical burden; in this line many have thrived to derive neurons from embryonic stem cells (ESC) in order to use them for cell transplantation. These studies are already yielding important information for future approaches in the field of cell therapies in PD but also in other neurodegenerative disorders where cell transplantation therapy may be considered. While the field of cell replacement therapies has been recently called into question with contrasting results in transplanted PD patients, these new sets of findings are raising new hopes and opening new avenues in this rejuvenated field. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  8. A novel, immortal, and multipotent human neural stem cell line generating functional neurons and oligodendrocytes.

    PubMed

    De Filippis, Lidia; Lamorte, Giuseppe; Snyder, Evan Y; Malgaroli, Antonio; Vescovi, Angelo L

    2007-09-01

    The discovery and study of neural stem cells have revolutionized our understanding of the neurogenetic process, and their inherent ability to adopt expansive growth behavior in vitro is of paramount importance for the development of novel therapeutics based on neural cell replacement. Recent advances in high-throughput assays for drug development and gene discovery dictate the need for rapid, reproducible, long-term expansion of human neural stem cells (hNSCs). In this view, the complement of wild-type cell lines currently available is insufficient. Here we report the establishment of a stable human neural stem cell line (immortalized human NSCs [IhNSCs]) by v-myc-mediated immortalization of previously derived wild-type hNSCs. These cells demonstrate three- to fourfold faster proliferation than wild-type cells in response to growth factors but retain rather similar properties, including multipotentiality. By molecular biology, biochemistry, immunocytochemistry, fluorescence microscopy, and electrophysiology, we show that upon growth factor removal, IhNSCs completely downregulate v-myc expression, cease proliferation, and differentiate terminally into three major neural lineages: astrocytes, oligodendrocytes, and neurons. The latter are functional, mature cells displaying clear-cut morphological and physiological features of terminally differentiated neurons, encompassing mostly the GABAergic, glutamatergic, and cholinergic phenotypes. Finally, IhNSCs produce bona fide oligodendrocytes in fractions up to 20% of total cell number. This is in contrast to the negligible propensity of hNSCs to generate oligodendroglia reported so far. Thus, we describe an immortalized hNSC line endowed with the properties of normal hNSCs and suitable for developing the novel, reliable assays and reproducible high-throughput gene and drug screening that are essential in both diagnostics and cell therapy studies.

  9. Small-Molecule-Directed Hepatocyte-Like Cell Differentiation of Human Pluripotent Stem Cells.

    PubMed

    Mathapati, Santosh; Siller, Richard; Impellizzeri, Agata A R; Lycke, Max; Vegheim, Karianne; Almaas, Runar; Sullivan, Gareth J

    2016-08-17

    Hepatocyte-like cells (HLCs) generated in vitro from human pluripotent stem cells (hPSCs) provide an invaluable resource for basic research, regenerative medicine, drug screening, toxicology, and modeling of liver disease and development. This unit describes a small-molecule-driven protocol for in vitro differentiation of hPSCs into HLCs without the use of growth factors. hPSCs are coaxed through a developmentally relevant route via the primitive streak to definitive endoderm (DE) using the small molecule CHIR99021 (a Wnt agonist), replacing the conventional growth factors Wnt3A and activin A. The small-molecule-derived DE is then differentiated to hepatoblast-like cells in the presence of dimethyl sulfoxide. The resulting hepatoblasts are then differentiated to HLCs with N-hexanoic-Tyr, Ile-6 aminohexanoic amide (Dihexa, a hepatocyte growth factor agonist) and dexamethasone. The protocol provides an efficient and reproducible procedure for differentiation of hPSCs into HLCs utilizing small molecules. © 2016 by John Wiley & Sons, Inc. Copyright © 2016 John Wiley & Sons, Inc.

  10. Long-term culture and cryopreservation does not affect the stability and functionality of human embryonic stem cell-derived hepatocyte-like cells.

    PubMed

    Mandal, Arundhati; Raju, Sheena; Viswanathan, Chandra

    2016-02-01

    Human embryonic stem cells (hESCs) are predicted to be an unlimited source of hepatocytes which can pave the way for applications such as cell replacement therapies or as a model of human development or even to predict the hepatotoxicity of drug compounds. We have optimized a 23-d differentiation protocol to generate hepatocyte-like cells (HLCs) from hESCs, obtaining a relatively pure population which expresses the major hepatic markers and is functional and mature. The stability of the HLCs in terms of hepato-specific marker expression and functionality was found to be intact even after an extended period of in vitro culture and cryopreservation. The hESC-derived HLCs have shown the capability to display sensitivity and an alteration in the level of CYP enzyme upon drug induction. This illustrates the potential of such assays in predicting the hepatotoxicity of a drug compound leading to advancement of pharmacology.

  11. Cloning of aged animals: a medical model for tissue and organ regeneration.

    PubMed

    Tian, X C; Kubota, C; Yang, X

    2001-11-01

    Cloning by nuclear transfer has great potential application in pharmaceutical protein production, xeno-transplantation, and perhaps most excitingly, therapeutic cloning. In therapeutic cloning a patient's own skin cells can be used to generate cloned embryos from which embryonic stem cells are isolated. Through targeted differentiation, embryonic stem cells can be directed to develop into the desired tissues/organs for replacement. The combination of homologous recombination of genes and nuclear transfer also offers the promise of correcting defective genes in humans. Demonstration of the successful cloning of aged animals is important for these future medical applications because degenerative diseases often afflict older adults. Our studies have demonstrated that skin fibroblast cells from aged adults, even after prolonged culture, provide nuclear donors equally as competent for cloning as cells from young adults or fetuses. These findings have paved the way for medically treating degenerative diseases of aged humans by tissue regeneration technologies made possible through cloning and homologous recombination.

  12. Heterogeneity of adult masseter muscle satellite cells with cardiomyocyte differentiation potential.

    PubMed

    Huang, Wei; Liang, Jialiang; Feng, Yuliang; Jia, Zhanfeng; Jiang, Lin; Cai, Wenfeng; Paul, Christian; Gu, Jianguo G; Stambrook, Peter J; Millard, Ronald W; Zhu, Xiao-Lan; Zhu, Ping; Wang, Yigang

    2018-05-26

    Although resident cardiac stem cells have been reported, regeneration of functional cardiomyocytes (CMs) remains a challenge. The present study identifies an alternative progenitor source for CM regeneration without the need for genetic manipulation or invasive heart biopsy procedures. Unlike limb skeletal muscles, masseter muscles (MM) in the mouse head are developed from Nkx2-5 mesodermal progenitors. Adult masseter muscle satellite cells (MMSCs) display heterogeneity in developmental origin and cell phenotypes. The heterogeneous MMSCs that can be characterized by cell sorting based on stem cell antigen-1 (Sca1) show different lineage potential. While cardiogenic potential is preserved in Sca1 + MMSCs as shown by expression of cardiac progenitor genes (including Nkx2-5), skeletal myogenic capacity is maintained in Sca1 - MMSCs with Pax7 expression. Sca1 + MMSC-derived beating cells express cardiac genes and exhibit CM-like morphology. Electrophysiological properties of MMSC-derived CMs are demonstrated by calcium transients and action potentials. These findings show that MMSCs could serve as a novel cell source for cardiomyocyte replacement. Copyright © 2018. Published by Elsevier Inc.

  13. A Customized Self-Assembling Peptide Hydrogel for Dental Pulp Tissue Engineering

    PubMed Central

    Hartgerink, Jeffrey D.; Cavender, Adriana C.; Schmalz, Gottfried

    2012-01-01

    Root canal therapy is common practice in dentistry. During this procedure, the inflamed or necrotic dental pulp is removed and replaced with a synthetic material. However, recent research provides evidence that engineering of dental pulp and dentin is possible by using biologically driven approaches. As tissue engineering strategies hold the promise to soon supersede conventional root canal treatment, there is a need for customized scaffolds for stem cell delivery or recruitment. We hypothesize that the incorporation of dental pulp-derived stem cells with bioactive factors into such a scaffold can promote cell proliferation, differentiation, and angiogenesis. In this study, we used a cell adhesive, enzyme-cleavable hydrogel made from self-assembling peptide nanofibers to encapsulate dental pulp stem cells. The growth factors (GFs) fibroblast growth factor basic, transforming growth factor β1, and vascular endothelial growth factor were incorporated into the hydrogel via heparin binding. Release profiles were established, and the influence of GFs on cell morphology and proliferation was assessed to confirm their bioactivity after binding and subsequent release. Cell morphology and spreading in three-dimensional cultures were visualized by using cell tracker and histologic stains. Subcutaneous transplantation of the hydrogel within dentin cylinders into immunocompromised mice led to the formation of a vascularized soft connective tissue similar to dental pulp. These data support the use of this novel biomaterial as a highly promising candidate for future treatment concepts in regenerative endodontics. PMID:21827280

  14. Effects of radial compression on a novel simulated intervertebral disc-like assembly using bone marrow-derived mesenchymal stem cell cell-sheets for annulus fibrosus regeneration.

    PubMed

    See, Eugene Yong-Shun; Toh, Siew Lok; Goh, James Cho-Hong

    2011-10-01

    The aim of this study was to develop a tissue engineering approach in regenerating the annulus fibrosus (AF) as part of an overall strategy to produce a tissue-engineered intervertebral disc (IVD) replacement. To determine whether a rehabilitative simulation regime on bone marrow–derived mesenchymal stem cell cell-sheet is able to aid the regeneration of the AF. No previous study has used bone marrow–derived mesenchymal stem cell cell-sheets simulated by a rehabilitative regime to regenerate the AF. The approach was to use bone marrow–derived stem cells to form cell-sheets and incorporating them onto silk scaffolds to simulate the native lamellae of the AF. The in vitro experimental model used to study the efficacy of such a system was made up of the tissue engineering AF construct wrapped around a silicone disc to form a simulated IVD-like assembly. The assembly was cultured within a custom-designed bioreactor that provided a compressive mechanical stimulation onto the silicone disc. The silicone nucleus pulposus would bulge radially and compress the simulated AF to mimic the physiological conditions. The simulated IVD-like assembly was compressed using a rehabilitative regime that lasted for 4 weeks at 0.25 Hz, for 15 minutes each day. With the rehabilitative regime, the cell-sheets remained viable but showed a decrease in cell numbers and viability. Gene expression analysis showed significant upregulation of IVD-related genes and there was an increased ratio of collagen type II to collagen type I found within the extracellular matrix. The results suggested that a rehabilitative regime caused extensive remodeling to take place within the simulated IVD-like assembly, producing extracellular matrix similar to that found in the inner AF.

  15. Low-molecular-weight carbohydrate Pentaisomaltose may replace dimethyl sulfoxide as a safer cryoprotectant for cryopreservation of peripheral blood stem cells.

    PubMed

    Svalgaard, Jesper Dyrendom; Haastrup, Eva Kannik; Reckzeh, Kristian; Holst, Bjørn; Glovinski, Peter Viktor; Gørløv, Jette Sønderskov; Hansen, Morten Bagge; Moench, Kim Theilgaard; Clausen, Christian; Fischer-Nielsen, Anne

    2016-05-01

    Cryopreserved hematopoietic stem cell products are widely used for certain hematologic malignancies. Dimethyl sulfoxide (DMSO) is the most widely used cryoprotective agent (CPA) today, but due to indications of cellular toxicity, changes of the cellular epigenetic state, and patient-related side effects, there is an increasing demand for DMSO-free alternatives. We therefore investigated whether Pentaisomaltose (PIM), a low-molecular-weight carbohydrate (1 kDa), can be used for cryopreservation of peripheral blood stem cells, more specifically hematopoietic progenitor cell apheresis (HPC(A)) product. We cryopreserved patient or donor HPC(A) products using 10% DMSO or 16% PIM and quantified the recovery of CD34+ cells and CD34+ subpopulations by multicolor flow cytometry. In addition, we compared the frequency of HPCs after DMSO and PIM cryopreservation using the colony-forming cells (CFCs) assay. The mean CD34+ cell recovery was 56.3 ± 23.7% (11.4%-97.3%) and 58.2 ± 10.0% (45.7%-76.9%) for 10% DMSO and 16% PIM, respectively. The distribution of CD34+ cell subpopulations was similar when comparing DMSO or PIM as CPA. CFC assay showed mean colony numbers of 70.7 ± 25.4 (range, 37.8-115.5) and 67.7 ± 15.7 (range, 48-86) for 10% DMSO and 16% PIM, respectively. Our findings demonstrate that PIM cryopreservation of HPC(A) products provides recovery of CD34+ cells, CD34+ subpopulations, and CFCs similar to that of DMSO cryopreservation and therefore may have the potential to be used for cryopreservation of peripheral blood stem cells. © 2016 The Authors Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

  16. Tissue Engineering Using Transfected Growth-Factor Genes

    NASA Technical Reports Server (NTRS)

    Madry, Henning; Langer, Robert S.; Freed, Lisa E.; Trippel, Stephen; Vunjak-Novakovic, Gordana

    2005-01-01

    A method of growing bioengineered tissues includes, as a major component, the use of mammalian cells that have been transfected with genes for secretion of regulator and growth-factor substances. In a typical application, one either seeds the cells onto an artificial matrix made of a synthetic or natural biocompatible material, or else one cultures the cells until they secrete a desired amount of an extracellular matrix. If such a bioengineered tissue construct is to be used for surgical replacement of injured tissue, then the cells should preferably be the patient s own cells or, if not, at least cells matched to the patient s cells according to a human-leucocyteantigen (HLA) test. The bioengineered tissue construct is typically implanted in the patient's injured natural tissue, wherein the growth-factor genes enhance metabolic functions that promote the in vitro development of functional tissue constructs and their integration with native tissues. If the matrix is biodegradable, then one of the results of metabolism could be absorption of the matrix and replacement of the matrix with tissue formed at least partly by the transfected cells. The method was developed for articular chondrocytes but can (at least in principle) be extended to a variety of cell types and biocompatible matrix materials, including ones that have been exploited in prior tissue-engineering methods. Examples of cell types include chondrocytes, hepatocytes, islet cells, nerve cells, muscle cells, other organ cells, bone- and cartilage-forming cells, epithelial and endothelial cells, connective- tissue stem cells, mesodermal stem cells, and cells of the liver and the pancreas. Cells can be obtained from cell-line cultures, biopsies, and tissue banks. Genes, molecules, or nucleic acids that secrete factors that influence the growth of cells, the production of extracellular matrix material, and other cell functions can be inserted in cells by any of a variety of standard transfection techniques.

  17. Nanotechnology & human stem cells: Applications in cardiogenesis and neurogenesis

    NASA Astrophysics Data System (ADS)

    Tomov, Martin L.

    Human stem cell research holds an unprecedented promise to revolutionize the way we approach medicine and healthcare in general, moving us from a position of mostly addressing the symptoms to a state where treatments can focus on removing the underlying causes of a condition. Stem cell research can shed light into normal developmental pathways, as we are beginning to replicate them in a petri dish and can also be used to model diseases and abnormal conditions. Direct applications can range from finding cures for single or multigene diseases to demonstrating that we can replace these genes with a normal copy. We can even begin to model lifelong conditions such as aging by iPSC technology by relying on fetal, young, adult, and centenarian populations to provide insights into the process. We have also begun to understand the microenvironment in which specific cell populations reside. Being able to replicate the chemical, physical mechanical, and spatial needs of those cells, research groups are successfully generating full organs using cadaver scaffolds of heart and kidney, and there is promising research to reach the same success with other organs, such as the liver, and pancreas. Advances in those areas open an enormous potential to study organs, organoids, organ valves, tubes or other functional elements such as beating cardiomyocytes in vitro. There is also the need to evaluate the whole genome of induced and differentiated cells, with its myriad of interacting pathways. Bioinformatics can help our understanding of embryogenesis, organ differentiation and function. It can also help optimize our stem cell and bio-scaffold tools to advance closer to functional organs and tissues. Such a combination approach will also include pluripotency evaluation and multi-lineage differentiation, as well as platforms that may assist in cell therapies: 3D structures, micro-ribbons, directed patterning to name a few. There is now a clearer path forward with stem cell research than was ever before possible. My research has made fundamental contributions to the stem cell field by detailed analysis of uniformly generated 3D stem cell intermediates that are embryoid bodies. I have also contributed to the derivation of the first fully characterized ethnically diverse induced pluripotent stem cells from minority populations (ED-iPSCs), and advances in generating functional beating cardiomyocytes in vitro to aid cardiomyoplasty therapies. My work has also explored scaffolds for directing neural cell assembly or encouraging self-assembly for applications in CNS neurodegeneration, addiction, and spinal cord injury. These contributions to the field are outlined in my Specific Aims below and detailed in the chapters of my thesis.

  18. The choice of facilitators in medical tourism.

    PubMed

    Gan, Lydia L; Frederick, James R

    2018-01-01

    The study identified which of the four facilitators (themselves, agents, insurers, or doctors) consumers are most likely to use when they travel for various medical procedures. A survey conducted between 2011 and 2014 yielded 964 responses. The multinomial logistic regression results showed that being 51-64 years old was positively related to going on their own or using agents to arrange for knee replacements. Having a high school education or less was positively linked to using both agents and insurers to facilitate knee replacements, whereas having a bachelor's degree was negatively associated with going on their own for stem cell therapy.

  19. Fusion of approaches to the treatment of organ failure.

    PubMed

    Ogle, Brenda; Cascalho, Marilia; Platt, Jeffrey L

    2004-01-01

    Because organ transplantation is the preferred treatment for organ failure, the demand for human organs for transplantation is large and growing. From this demand, several fields based on new technologies for the replacement or repair of damaged tissues and organs have emerged. These fields include stem cell biology, cloning, tissue engineering and xenotransplantation. Here we evaluate the potential contribution of these to the devising of alternative approaches to organ replacement. We present our vision for the development of two structurally complex organs - the lung and the kidney - based on a 'fusion' of new and established technologies.

  20. The quest to make fully functional human pancreatic beta cells from embryonic stem cells: climbing a mountain in the clouds.

    PubMed

    Johnson, James D

    2016-10-01

    The production of fully functional insulin-secreting cells to treat diabetes is a major goal of regenerative medicine. In this article, I review progress towards this goal over the last 15 years from the perspective of a beta cell biologist. I describe the current state-of-the-art, and speculate on the general approaches that will be required to identify and achieve our ultimate goal of producing functional beta cells. The need for deeper phenotyping of heterogeneous cultures of stem cell derived islet-like cells in parallel with a better understanding of the heterogeneity of the target cell type(s) is emphasised. This deep phenotyping should include high-throughput single-cell analysis, as well as comprehensive 'omics technologies to provide unbiased characterisation of cell products and human beta cells. There are justified calls for more detailed and well-powered studies of primary human pancreatic beta cell physiology, and I propose online databases of standardised human beta cell responses to physiological stimuli, including both functional and metabolomic/proteomic/transcriptomic profiles. With a concerted, community-wide effort, including both basic and applied scientists, beta cell replacement will become a clinical reality for patients with diabetes.

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