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Sample records for adult tissue stem

  1. Strategies to Optimize Adult Stem Cell Therapy for Tissue Regeneration.

    PubMed

    Liu, Shan; Zhou, Jingli; Zhang, Xuan; Liu, Yang; Chen, Jin; Hu, Bo; Song, Jinlin; Zhang, Yuanyuan

    2016-06-21

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

  2. Strategies to Optimize Adult Stem Cell Therapy for Tissue Regeneration

    PubMed Central

    Liu, Shan; Zhou, Jingli; Zhang, Xuan; Liu, Yang; Chen, Jin; Hu, Bo; Song, Jinlin; Zhang, Yuanyuan

    2016-01-01

    Stem cell therapy aims to replace damaged or aged cells with healthy functioning cells in congenital defects, tissue injuries, autoimmune disorders, and neurogenic degenerative diseases. Among various types of stem cells, adult stem cells (i.e., tissue-specific stem cells) commit to becoming the functional cells from their tissue of origin. These cells are the most commonly used in cell-based therapy since they do not confer risk of teratomas, do not require fetal stem cell maneuvers and thus are free of ethical concerns, and they confer low immunogenicity (even if allogenous). The goal of this review is to summarize the current state of the art and advances in using stem cell therapy for tissue repair in solid organs. Here we address key factors in cell preparation, such as the source of adult stem cells, optimal cell types for implantation (universal mesenchymal stem cells vs. tissue-specific stem cells, or induced vs. non-induced stem cells), early or late passages of stem cells, stem cells with endogenous or exogenous growth factors, preconditioning of stem cells (hypoxia, growth factors, or conditioned medium), using various controlled release systems to deliver growth factors with hydrogels or microspheres to provide apposite interactions of stem cells and their niche. We also review several approaches of cell delivery that affect the outcomes of cell therapy, including the appropriate routes of cell administration (systemic, intravenous, or intraperitoneal vs. local administration), timing for cell therapy (immediate vs. a few days after injury), single injection of a large number of cells vs. multiple smaller injections, a single site for injection vs. multiple sites and use of rodents vs. larger animal models. Future directions of stem cell-based therapies are also discussed to guide potential clinical applications. PMID:27338364

  3. Concise Review: Quiescence in Adult Stem Cells: Biological Significance and Relevance to Tissue Regeneration.

    PubMed

    Rumman, Mohammad; Dhawan, Jyotsna; Kassem, Moustapha

    2015-10-01

    Adult stem cells (ASCs) are tissue resident stem cells responsible for tissue homeostasis and regeneration following injury. In uninjured tissues, ASCs exist in a nonproliferating, reversibly cell cycle-arrested state known as quiescence or G0. A key function of the quiescent state is to preserve stemness in ASCs by preventing precocious differentiation, and thus maintaining a pool of undifferentiated ASCs. Recent evidences suggest that quiescence is an actively maintained state and that excessive or defective quiescence may lead to compromised tissue regeneration or tumorigenesis. The aim of this review is to provide an update regarding the biological mechanisms of ASC quiescence and their role in tissue regeneration.

  4. Great promise of tissue-resident adult stem/progenitor cells in transplantation and cancer therapies.

    PubMed

    Mimeault, Murielle; Batra, Surinder K

    2012-01-01

    Recent progress in tissue-resident adult stem/progenitor cell research has inspired great interest because these immature cells from your own body can act as potential, easily accessible cell sources for cell transplantation in regenerative medicine and cancer therapies. The use of adult stem/progenitor cells endowed with a high self-renewal ability and multilineage differentiation potential, which are able to regenerate all the mature cells in the tissues from their origin, offers great promise in replacing non-functioning or lost cells and regenerating diseased and damaged tissues. The presence of a small subpopulation of adult stem/progenitor cells in most tissues and organs provides the possibility of stimulating their in vivo differentiation, or of using their ex vivo expanded progenies for cell-replacement and gene therapies with multiple applications in humans without a high-risk of graft rejection and major side effects. Among the diseases that could be treated by adult stem cell-based therapies are hematopoietic and immune disorders, multiple degenerative disorders such as Parkinson's and Alzheimer's diseases, Types 1 and 2 diabetes mellitus as well as skin, eye, liver, lung, tooth and cardiovascular disorders. In addition, a combination of the current cancer treatments with an adjuvant treatment consisting of an autologous or allogeneic adult stem/progenitor cell transplantation also represents a promising strategy for treating and even curing diverse aggressive, metastatic, recurrent and lethal cancers. In this chapter, we reviewed the most recent advancements on the characterization of phenotypic and functional properties of adult stem/progenitor cell types found in bone marrow, heart, brain and other tissues and discussed their therapeutic implications in the stem cell-based transplantation therapy.

  5. Fetal and adult liver stem cells for liver regeneration and tissue engineering.

    PubMed

    Fiegel, H C; Lange, Claudia; Kneser, U; Lambrecht, W; Zander, A R; Rogiers, X; Kluth, D

    2006-01-01

    For the development of innovative cell-based liver directed therapies, e.g. liver tissue engineering, the use of stem cells might be very attractive to overcome the limitation of donor liver tissue. Liver specific differentiation of embryonic, fetal or adult stem cells is currently under investigation. Different types of fetal liver (stem) cells during development were identified, and their advantageous growth potential and bipotential differentiation capacity were shown. However, ethical and legal issues have to be addressed before using fetal cells. Use of adult stem cells is clinically established, e.g. transplantation of hematopoietic stem cells. Other bone marrow derived liver stem cells might be mesenchymal stem cells (MSC). However, the transdifferentiation potential is still in question due to the observation of cellular fusion in several in vivo experiments. In vitro experiments revealed a crucial role of the environment (e.g. growth factors and extracellular matrix) for specific differentiation of stem cells. Co-cultured liver cells also seemed to be important for hepatic gene expression of MSC. For successful liver cell transplantation, a novel approach of tissue engineering by orthotopic transplantation of gel-immobilized cells could be promising, providing optimal environment for the injected cells. Moreover, an orthotopic tissue engineering approach using bipotential stem cells could lead to a repopulation of the recipients liver with healthy liver and biliary cells, thus providing both hepatic functions and biliary excretion. Future studies have to investigate, which stem cell and environmental conditions would be most suitable for the use of stem cells for liver regeneration or tissue engineering approaches.

  6. Muscle regeneration by adipose tissue-derived adult stem cells attached to injectable PLGA spheres.

    PubMed

    Kim, MiJung; Choi, Yu Suk; Yang, Seung Hye; Hong, Hea-Nam; Cho, Sung-Woo; Cha, Sang Myun; Pak, Jhang Ho; Kim, Chan Wha; Kwon, Seog Woon; Park, Chan Jeoung

    2006-09-22

    The [corrected] use of adult stem cells for cell-based tissue engineering and regeneration strategies represents a promising approach for skeletal muscle repair. We have evaluated the combination of adipose tissue-derived adult stem cells (ADSCs) obtained from autologous liposuction and injectable poly(lactic-co-glycolic acid) (PLGA) spheres for muscle regeneration. ADSCs attached to PLGA spheres and PLGA spheres alone were cultured in myogenic medium for 21 days and injected subcutaneously into the necks of nude mice. After 30 and 60 days, the mice were sacrificed, and newly formed tissues were analyzed by immunostaining, H and E staining, and RT-PCR. We found that ADSCs attached to PLGA spheres, but not PLGA spheres alone, were able to generate muscle tissue. These findings suggest that ADSCs and PLGA spheres are useful materials for muscle tissue engineering and that their combination can be used in clinical settings for muscle regeneration.

  7. A hypothesis for an embryonic origin of pluripotent Oct-4(+) stem cells in adult bone marrow and other tissues.

    PubMed

    Ratajczak, M Z; Machalinski, B; Wojakowski, W; Ratajczak, J; Kucia, M

    2007-05-01

    Accumulating evidence demonstrates that adult tissues contain a population of stem cells that express early developmental markers such as stage-specific embryonic antigen and transcription factors Oct-4 and Nanog. These are the markers characteristic for embryonic stem cells, epiblast stem cells and primordial germ cells. The presence of these stem cells in adult tissues including bone marrow, epidermis, bronchial epithelium, myocardium, pancreas and testes supports the concept that adult tissues contain some population of pluripotent stem cells that is deposited in embryogenesis during early gastrulation. In this review we will discuss these data and present a hypothesis that these cells could be direct descendants of the germ lineage. The germ lineage in order to pass genes on to the next generations creates soma and thus becomes a 'mother lineage' for all somatic cell lineages present in the adult body.

  8. A mystery unraveled: nontumorigenic pluripotent stem cells in human adult tissues

    PubMed Central

    Simerman, Ariel A; Perone, Marcelo J; Gimeno, María L; Dumesic, Daniel A; Chazenbalk, Gregorio D

    2014-01-01

    Introduction: Embryonic stem cells and induced pluripotent stem cells have emerged as the gold standard of pluripotent stem cells and the class of stem cell with the highest potential for contribution to regenerative and therapeutic application; however, their translational use is often impeded by teratoma formation, commonly associated with pluripotency. We discuss a population of nontumorigenic pluripotent stem cells, termed Multilineage Differentiating Stress Enduring (Muse) cells, which offer an innovative and exciting avenue of exploration for the potential treatment of various human diseases. Areas covered: This review discusses the origin of Muse cells, describes in detail their various unique characteristics, and considers future avenues of their application and investigation with respect to what is currently known of adult pluripotent stem cells in scientific literature. We begin by defining cell potency, then discuss both mesenchymal and various reported populations of pluripotent stem cells, and finally delve into Muse cells and the characteristics that set them apart from their contemporaries. Expert opinion: Muse cells derived from adipose tissue (Muse-AT) are efficiently, routinely and painlessly isolated from human lipoaspirate material, exhibit tripoblastic differentiation both spontaneously and under media-specific induction, and do not form teratomas. We describe qualities specific to Muse-AT cells and their potential impact on the field of regenerative medicine and cell therapy. PMID:24745973

  9. Embryonic origin of adult stem cells required for tissue homeostasis and regeneration.

    PubMed

    Davies, Erin L; Lei, Kai; Seidel, Christopher W; Kroesen, Amanda E; McKinney, Sean A; Guo, Longhua; Robb, Sofia Mc; Ross, Eric J; Gotting, Kirsten; Alvarado, Alejandro Sánchez

    2017-01-10

    Planarian neoblasts are pluripotent, adult somatic stem cells and lineage-primed progenitors that are required for the production and maintenance of all differentiated cell types, including the germline. Neoblasts, originally defined as undifferentiated cells residing in the adult parenchyma, are frequently compared to embryonic stem cells yet their developmental origin remains obscure. We investigated the provenance of neoblasts during Schmidtea mediterranea embryogenesis, and report that neoblasts arise from an anarchic, cycling piwi-1+ population wholly responsible for production of all temporary and definitive organs during embryogenesis. Early embryonic piwi-1+ cells are molecularly and functionally distinct from neoblasts: they express unique cohorts of early embryo enriched transcripts and behave differently than neoblasts in cell transplantation assays. Neoblast lineages arise as organogenesis begins and are required for construction of all major organ systems during embryogenesis. These subpopulations are continuously generated during adulthood, where they act as agents of tissue homeostasis and regeneration.

  10. Adult stem cells, scaffolds for in vivo and in vitro myocardial tissue engineering.

    PubMed

    Di Felice, Valentina; De Luca, Angela; Serradifalco, Claudia; Di Marco, Patrizia; Verin, Lucia; Motta, Antonella; Guercio, Annalisa; Zummo, Giovanni

    2010-01-01

    The main goal in the last few years in cardiac research has been to isolate cardiac potential stem cells from adult myocardium and to demonstrate their differentiation potential. We have previously demonstrated that c-Kit positive cardiac stem cells are able to organize themselves into a tissue-like cell mass. In this 3D mass, they can produce a high concentration of natural extracellular matrix, can create vessels, a capsule and, with the help of an Open-pore Polylactic Acid scaffold, many cells can organize an elementary myocardium. Drawing from this background, we decided to design and use poly-lactic scaffolds and the model of the athymic Nude-Foxn1(nu) mouse to evaluate the extent of the myogenic vs endothelial differentiation in vivo, and to evaluate the presence or the absence of a foreign body reaction.

  11. Ex-Vivo Tissues Engineering Modeling for Reconstructive Surgery Using Human Adult Adipose Stem Cells and Polymeric Nanostructured Matrix

    PubMed Central

    Morena, Francesco; Argentati, Chiara; Calzoni, Eleonora; Cordellini, Marino; Emiliani, Carla; D’Angelo, Francesco; Martino, Sabata

    2016-01-01

    The major challenge for stem cell translation regenerative medicine is the regeneration of damaged tissues by creating biological substitutes capable of recapitulating the missing function in the recipient host. Therefore, the current paradigm of tissue engineering strategies is the combination of a selected stem cell type, based on their capability to differentiate toward committed cell lineages, and a biomaterial, that, due to own characteristics (e.g., chemical, electric, mechanical property, nano-topography, and nanostructured molecular components), could serve as active scaffold to generate a bio-hybrid tissue/organ. Thus, effort has been made on the generation of in vitro tissue engineering modeling. Here, we present an in vitro model where human adipose stem cells isolated from lipoaspirate adipose tissue and breast adipose tissue, cultured on polymeric INTEGRA® Meshed Bilayer Wound Matrix (selected based on conventional clinical applications) are evaluated for their potential application for reconstructive surgery toward bone and adipose tissue. We demonstrated that human adipose stem cells isolated from lipoaspirate and breast tissue have similar stemness properties and are suitable for tissue engineering applications. Finally, the overall results highlighted lipoaspirate adipose tissue as a good source for the generation of adult adipose stem cells.

  12. Tissue-specific mutation accumulation in human adult stem cells during life

    NASA Astrophysics Data System (ADS)

    Blokzijl, Francis; de Ligt, Joep; Jager, Myrthe; Sasselli, Valentina; Roerink, Sophie; Sasaki, Nobuo; Huch, Meritxell; Boymans, Sander; Kuijk, Ewart; Prins, Pjotr; Nijman, Isaac J.; Martincorena, Inigo; Mokry, Michal; Wiegerinck, Caroline L.; Middendorp, Sabine; Sato, Toshiro; Schwank, Gerald; Nieuwenhuis, Edward E. S.; Verstegen, Monique M. A.; van der Laan, Luc J. W.; de Jonge, Jeroen; Ijzermans, Jan N. M.; Vries, Robert G.; van de Wetering, Marc; Stratton, Michael R.; Clevers, Hans; Cuppen, Edwin; van Boxtel, Ruben

    2016-10-01

    The gradual accumulation of genetic mutations in human adult stem cells (ASCs) during life is associated with various age-related diseases, including cancer. Extreme variation in cancer risk across tissues was recently proposed to depend on the lifetime number of ASC divisions, owing to unavoidable random mutations that arise during DNA replication. However, the rates and patterns of mutations in normal ASCs remain unknown. Here we determine genome-wide mutation patterns in ASCs of the small intestine, colon and liver of human donors with ages ranging from 3 to 87 years by sequencing clonal organoid cultures derived from primary multipotent cells. Our results show that mutations accumulate steadily over time in all of the assessed tissue types, at a rate of approximately 40 novel mutations per year, despite the large variation in cancer incidence among these tissues. Liver ASCs, however, have different mutation spectra compared to those of the colon and small intestine. Mutational signature analysis reveals that this difference can be attributed to spontaneous deamination of methylated cytosine residues in the colon and small intestine, probably reflecting their high ASC division rate. In liver, a signature with an as-yet-unknown underlying mechanism is predominant. Mutation spectra of driver genes in cancer show high similarity to the tissue-specific ASC mutation spectra, suggesting that intrinsic mutational processes in ASCs can initiate tumorigenesis. Notably, the inter-individual variation in mutation rate and spectra are low, suggesting tissue-specific activity of common mutational processes throughout life.

  13. Isolation of pluripotent neural crest-derived stem cells from adult human tissues by connexin-43 enrichment.

    PubMed

    Pelaez, Daniel; Huang, Chun-Yuh Charles; Cheung, Herman S

    2013-11-01

    Identification and isolation of pluripotent stem cells in adult tissues represent an important advancement in the fields of stem cell biology and regenerative medicine. For several years, research has been performed on the identification of biomarkers that can isolate stem cells residing in neural crest (NC)-derived adult tissues. The NC is considered a good model in stem cell biology as cells from it migrate extensively and contribute to the formation of diverse tissues in the body during organogenesis. Migration of these cells is modulated, in part, by gap junction communication among the cell sheets. Here we present a study in which, selection of connexin 43 (Cx43) expressing cells from human adult periodontal ligament yields a novel pluripotent stem cell population. Cx43⁺ periodontal ligament stem cells express pluripotency-associated transcription factors OCT4, Nanog, and Sox2, as well as NC-specific markers Sox10, p75, and Nestin. When injected in vivo into an immunodeficient mouse model, these cells were capable of generating teratomas with tissues from the three embryological germ layers: endoderm, mesoderm, and ectoderm. Furthermore, the cells formed mature structures of tissues normally arising from the NC during embryogenesis such as eccrine sweat glands of the human skin, muscle, neuronal tissues, cartilage, and bone. Immunohistochemical analysis confirmed the human origin of the neoplastic cells as well as the ectodermal and endodermal nature of some of the structures found in the tumors. These results suggest that Cx43 may be used as a biomarker to select and isolate the remnant NC pluripotent stem cells from adult human tissues arising from this embryological structure. The isolation of these cells through routine medical procedures such as wisdom teeth extraction further enhances their applicability to the regenerative medicine field.

  14. Embryonic origin of adult stem cells required for tissue homeostasis and regeneration

    PubMed Central

    Davies, Erin L; Lei, Kai; Seidel, Christopher W; Kroesen, Amanda E; McKinney, Sean A; Guo, Longhua; Robb, Sofia MC; Ross, Eric J; Gotting, Kirsten; Alvarado, Alejandro Sánchez

    2017-01-01

    Planarian neoblasts are pluripotent, adult somatic stem cells and lineage-primed progenitors that are required for the production and maintenance of all differentiated cell types, including the germline. Neoblasts, originally defined as undifferentiated cells residing in the adult parenchyma, are frequently compared to embryonic stem cells yet their developmental origin remains obscure. We investigated the provenance of neoblasts during Schmidtea mediterranea embryogenesis, and report that neoblasts arise from an anarchic, cycling piwi-1+ population wholly responsible for production of all temporary and definitive organs during embryogenesis. Early embryonic piwi-1+ cells are molecularly and functionally distinct from neoblasts: they express unique cohorts of early embryo enriched transcripts and behave differently than neoblasts in cell transplantation assays. Neoblast lineages arise as organogenesis begins and are required for construction of all major organ systems during embryogenesis. These subpopulations are continuously generated during adulthood, where they act as agents of tissue homeostasis and regeneration. DOI: http://dx.doi.org/10.7554/eLife.21052.001 PMID:28072387

  15. Transcription levels of sirtuin family in neural stem cells and brain tissues of adult mice.

    PubMed

    Wang, H F; Li, Q; Feng, R L; Wen, T Q

    2012-09-10

    Neural stem cells (NSCs) has been used as a well-known model to investigate apoptosis, differentiation, maintenance of stem cells status, and therapy of neurological disease. The C17.2 NSCs line was produced after v-myc transformation of neural progenitor from mouse cerebellar cortex. Sirtuin family plays important roles involved in neuronal differentiation, genomic stability, lifespan, cell survival. However, little is known about gene expression variation of sirtuin family in C17.2 NSCs, primary NSCs, and different brain tissues in adult mice. Here, we confirmed that the mRNA expression levels of sirt2, 3, 4, 5, and 7 in E14.5 NSCs were significantly higher than in C17.2 NSCs, whereas that sirt 6 displayed an opposing mode. Moreover, a higher mRNA level of sirtuin family was observed in the adult mouse brain compared to C17.2 NSCs. In addition, histone deacetylase (HDAC) inhibitors nicotinamide and Trichostatin A (TSA) were used to explore differential changes at the transcriptional level of sirtuins. Results indicated that the expression of sirt1, sirt5 and sirt6 was significant downregulated by nicotinamide treatment. Whereas, a significant downregulation in sirt1 and sirt3 and a significant upregulation in sirt2, sirt4, sirt6, and sirt7 were observed in the treatment of TSA. Thus our studies indicate different sirtuin mRNA expression profiles between C17.2 NSCs, E14.5 NSCs and brain tissues, suggesting the transcriptional regulation of sirtuin family could be mediated by different histone acetylation.

  16. Repair of tissues by adult stem/progenitor cells (MSCs): controversies, myths, and changing paradigms.

    PubMed

    Prockop, Darwin J

    2009-06-01

    Research on stem cells has progressed at a rapid pace and, as might be anticipated, the results have generated several controversies, a few myths and a change in a major paradigm. Some of these issues will be reviewed in this study with special emphasis on how they can be applied to the adult stem/progenitor cells from bone marrow, referred to as MSCs.

  17. Adult marrow-derived very small embryonic-like stem cells and tissue engineering.

    PubMed

    Kucia, Magda; Zuba-Surma, Ewa K; Wysoczynski, Marcin; Wu, Wan; Ratajczak, Janina; Machalinski, Boguslaw; Ratajczak, Mariusz Z

    2007-10-01

    A population of CXCR4(+) lin(-) CD45(-) cells that express SSEA, Oct-4 and Nanog has been identified in adult bone marrow. These cells are very small and display several features typical for primary embryonic stem cells such as: i) a large nuclei surrounded by a narrow rim of cytoplasm; ii) open-type chromatin (euchromatin); and iii) high telomerase activity. These cells were named very small embryonic-like stem cells (VSEL-SC). The authors hypothesized that they are direct descendants of the germ lineage. Germ lineage, in order to pass genes on to the next generation, has to create soma and thus becomes a 'mother lineage' for all somatic cell lineages present in the adult body. Germ potential is established after conception in a totipotent zygote and retained subsequently during development in blastomers of morula, cells form the inner cell mass of blastocyst, epiblast and population of primordial germ cells. The authors envision that VSEL-SC are epiblast-derived pluripotent stem cells and could potentially become a less-controversial source of stem cells for regeneration.

  18. Adult stem cell therapy: dream or reality?

    PubMed

    Moraleda, Jose M; Blanquer, Miguel; Bleda, Patricia; Iniesta, Paqui; Ruiz, Francisco; Bonilla, Sonia; Cabanes, Carmen; Tabares, Lucía; Martinez, Salvador

    2006-12-01

    Adult stem cells may be an invaluable source of plastic cells for tissue regeneration. The bone marrow contains different subpopulations of adult stem cells easily accessible for transplantation. However the therapeutic value of adult stem cell is a question of debate in the scientific community. We have investigated the potential benefits of adult hematopoietic stem cell transplantation in animal models of demyelinating and motor neuron diseases. Our results suggest that transplantation of HSC have direct and indirect neuroregenerative and neuroprotective effects.

  19. The circadian clock in skin: implications for adult stem cells, tissue regeneration, cancer, aging, and immunity

    PubMed Central

    Plikus, Maksim V.; Van Spyk, Elyse Noelani; Pham, Kim; Geyfman, Mikhail; Kumar, Vivek; Takahashi, Joseph S.; Andersen, Bogi

    2015-01-01

    Historically work on peripheral circadian clocks has been focused on organs and tissues that have prominent metabolic functions, such as liver, fat and muscle. In recent years, skin is emerging as a model for studying circadian clock regulation of cell proliferation, stem cell functions, tissue regeneration, aging and carcinogenesis. Morphologically skin is complex, containing multiple cell types and structures, and there is evidence for a functional circadian clock in most, if not all, of its cell types. Despite the complexity, skin stem cell populations are well defined, experimentally tractable and exhibit prominent daily cell proliferation cycles. Hair follicle stem cells also participate in recurrent, long-lasting cycles of regeneration -- the hair growth cycles. Among other advantages of skin is a broad repertoire of available genetic tools enabling the creation of cell-type specific circadian mutants. Also, due to the accessibility of the skin, in vivo imaging techniques can be readily applied to study the circadian clock and its outputs in real time, even at the single-cell level. Skin provides the first line of defense against many environmental and stress factors that exhibit dramatic diurnal variations such as solar UV radiation and temperature. Studies have already linked the circadian clock to the control of UVB-induced DNA damage and skin cancers. Due to the important role that skin plays in the defense against microorganisms, it represents a promising model system to further explore the role of the clock in the regulation of the body's immune functions. To that end, recent studies have already linked the circadian clock to psoriasis, one of the most common immune-mediated skin disorders. The skin also provides opportunities to interrogate clock regulation of tissue metabolism in the context of stem cells and regeneration. Furthermore, many animal species feature prominent seasonal hair molt cycles, offering an attractive model for investigating the

  20. The circadian clock in skin: implications for adult stem cells, tissue regeneration, cancer, aging, and immunity.

    PubMed

    Plikus, Maksim V; Van Spyk, Elyse N; Pham, Kim; Geyfman, Mikhail; Kumar, Vivek; Takahashi, Joseph S; Andersen, Bogi

    2015-06-01

    Historically, work on peripheral circadian clocks has been focused on organs and tissues that have prominent metabolic functions, such as the liver, fat, and muscle. In recent years, skin has emerged as a model for studying circadian clock regulation of cell proliferation, stem cell functions, tissue regeneration, aging, and carcinogenesis. Morphologically, skin is complex, containing multiple cell types and structures, and there is evidence for a functional circadian clock in most, if not all, of its cell types. Despite the complexity, skin stem cell populations are well defined, experimentally tractable, and exhibit prominent daily cell proliferation cycles. Hair follicle stem cells also participate in recurrent, long-lasting cycles of regeneration: the hair growth cycles. Among other advantages of skin is a broad repertoire of available genetic tools enabling the creation of cell type-specific circadian mutants. Also, due to the accessibility of skin, in vivo imaging techniques can be readily applied to study the circadian clock and its outputs in real time, even at the single-cell level. Skin provides the first line of defense against many environmental and stress factors that exhibit dramatic diurnal variations such as solar ultraviolet (UV) radiation and temperature. Studies have already linked the circadian clock to the control of UVB-induced DNA damage and skin cancers. Due to the important role that skin plays in the defense against microorganisms, it also represents a promising model system to further explore the role of the clock in the regulation of the body's immune functions. To that end, recent studies have already linked the circadian clock to psoriasis, one of the most common immune-mediated skin disorders. Skin also provides opportunities to interrogate the clock regulation of tissue metabolism in the context of stem cells and regeneration. Furthermore, many animal species feature prominent seasonal hair molt cycles, offering an attractive model

  1. Effects of FGF-2 on human adipose tissue derived adult stem cells morphology and chondrogenesis enhancement in Transwell culture

    SciTech Connect

    Kabiri, Azadeh; Esfandiari, Ebrahim; Hashemibeni, Batool; Kazemi, Mohammad; Mardani, Mohammad; Esmaeili, Abolghasem

    2012-07-27

    Highlights: Black-Right-Pointing-Pointer We investigated effects of FGF-2 on hADSCs. Black-Right-Pointing-Pointer We examine changes in the level of gene expressions of SOX-9, aggrecan and collagen type II and type X. Black-Right-Pointing-Pointer FGF-2 induces chondrogenesis in hADSCs, which Bullet Increasing information will decrease quality if hospital costs are very different. Black-Right-Pointing-Pointer The result of this study may be beneficial in cartilage tissue engineering. -- Abstract: Injured cartilage is difficult to repair due to its poor vascularisation. Cell based therapies may serve as tools to more effectively regenerate defective cartilage. Both adult mesenchymal stem cells (MSCs) and human adipose derived stem cells (hADSCs) are regarded as potential stem cell sources able to generate functional cartilage for cell transplantation. Growth factors, in particular the TGF-b superfamily, influence many processes during cartilage formation, including cell proliferation, extracellular matrix synthesis, maintenance of the differentiated phenotype, and induction of MSCs towards chondrogenesis. In the current study, we investigated the effects of FGF-2 on hADSC morphology and chondrogenesis in Transwell culture. hADSCs were obtained from patients undergoing elective surgery, and then cultured in expansion medium alone or in the presence of FGF-2 (10 ng/ml). mRNA expression levels of SOX-9, aggrecan and collagen type II and type X were quantified by real-time polymerase chain reaction. The morphology, doubling time, trypsinization time and chondrogenesis of hADSCs were also studied. Expression levels of SOX-9, collagen type II, and aggrecan were all significantly increased in hADSCs expanded in presence of FGF-2. Furthermore FGF-2 induced a slender morphology, whereas doubling time and trypsinization time decreased. Our results suggest that FGF-2 induces hADSCs chondrogenesis in Transwell culture, which may be beneficial in cartilage tissue engineering.

  2. Hematopoietic stem cell origin of connective tissues.

    PubMed

    Ogawa, Makio; Larue, Amanda C; Watson, Patricia M; Watson, Dennis K

    2010-07-01

    Connective tissue consists of "connective tissue proper," which is further divided into loose and dense (fibrous) connective tissues and "specialized connective tissues." Specialized connective tissues consist of blood, adipose tissue, cartilage, and bone. In both loose and dense connective tissues, the principal cellular element is fibroblasts. It has been generally believed that all cellular elements of connective tissue, including fibroblasts, adipocytes, chondrocytes, and bone cells, are generated solely by mesenchymal stem cells. Recently, a number of studies, including those from our laboratory based on transplantation of single hematopoietic stem cells, strongly suggested a hematopoietic stem cell origin of these adult mesenchymal tissues. This review summarizes the experimental evidence for this new paradigm and discusses its translational implications.

  3. Generalized Potential of Adult Neural Stem Cells

    NASA Astrophysics Data System (ADS)

    Clarke, Diana L.; Johansson, Clas B.; Wilbertz, Johannes; Veress, Biborka; Nilsson, Erik; Karlström, Helena; Lendahl, Urban; Frisén, Jonas

    2000-06-01

    The differentiation potential of stem cells in tissues of the adult has been thought to be limited to cell lineages present in the organ from which they were derived, but there is evidence that some stem cells may have a broader differentiation repertoire. We show here that neural stem cells from the adult mouse brain can contribute to the formation of chimeric chick and mouse embryos and give rise to cells of all germ layers. This demonstrates that an adult neural stem cell has a very broad developmental capacity and may potentially be used to generate a variety of cell types for transplantation in different diseases.

  4. Muse Cells: Nontumorigenic Pluripotent Stem Cells Present in Adult Tissues—A Paradigm Shift in Tissue Regeneration and Evolution

    PubMed Central

    2016-01-01

    Muse cells are a novel population of nontumorigenic pluripotent stem cells, highly resistant to cellular stress. These cells are present in every connective tissue and intrinsically express pluripotent stem markers such as Nanog, Oct3/4, Sox2, and TRA1-60. Muse cells are able to differentiate into cells from all three embryonic germ layers both spontaneously and under media-specific induction. Unlike ESCs and iPSCs, Muse cells exhibit low telomerase activity and asymmetric division and do not undergo tumorigenesis or teratoma formation when transplanted into a host organism. Muse cells have a high capacity for homing into damaged tissue and spontaneous differentiation into cells of compatible tissue, leading to tissue repair and functional restoration. The ability of Muse cells to restore tissue function may demonstrate the role of Muse cells in a highly conserved cellular mechanism related to cell survival and regeneration, in response to cellular stress and acute injury. From an evolutionary standpoint, genes pertaining to the regenerative capacity of an organism have been lost in higher mammals from more primitive species. Therefore, Muse cells may offer insight into the molecular and evolutionary bases of autonomous tissue regeneration and elucidate the molecular and cellular mechanisms that prevent mammals from regenerating limbs and organs, as planarians, newts, zebrafish, and salamanders do. PMID:28070194

  5. The E3 ligase axotrophin/MARCH-7: protein expression profiling of human tissues reveals links to adult stem cells.

    PubMed

    Szigyarto, Cristina A; Sibbons, Paul; Williams, Gill; Uhlen, Mathias; Metcalfe, Su M

    2010-04-01

    Axotrophin/MARCH-7 was first identified in mouse embryonic stem cells as a neural stem cell gene. Using the axotrophin/MARCH-7 null mouse, we discovered profound effects on T lymphocyte responses, including 8-fold hyperproliferation and 5-fold excess release of the stem cell cytokine leukemia inhibitory factor (LIF). Our further discovery that axotrophin/MARCH-7 is required for targeted degradation of the LIF receptor subunit gp190 implies a direct role in the regulation of LIF signaling. Bioinformatics studies revealed a highly conserved RING-CH domain in common with the MARCH family of E3-ubiquitin ligases, and accordingly, axotrophin was renamed "MARCH-7." To probe protein expression of human axotrophin/MARCH-7, we prepared antibodies against different domains of the protein. Each antibody bound its specific target epitope with high affinity, and immunohistochemistry cross-validated target specificity. Forty-eight human tissue types were screened. Epithelial cells stained strongly, with trophoblasts having the greatest staining. In certain tissues, specific cell types were selectively positive, including neurons and neuronal progenitor cells in the hippocampus and cerebellum, endothelial sinusoids of the spleen, megakaryocytes in the bone marrow, crypt stem cells of the small intestine, and alveolar macrophages in the lung. Approximately 20% of central nervous system neuropils were positive. Notably, axotrophin/MARCH-7 has an expression profile that is distinct from that of other MARCH family members. This manuscript contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.

  6. A multistep procedure to prepare pre-vascularized cardiac tissue constructs using adult stem sells, dynamic cell cultures, and porous scaffolds

    PubMed Central

    Pagliari, Stefania; Tirella, Annalisa; Ahluwalia, Arti; Duim, Sjoerd; Goumans, Marie-Josè; Aoyagi, Takao; Forte, Giancarlo

    2014-01-01

    The vascularization of tissue engineered products represents a key issue in regenerative medicine which needs to be addressed before the translation of these protocols to the bedside can be foreseen. Here we propose a multistep procedure to prepare pre-vascularized three-dimensional (3D) cardiac bio-substitutes using dynamic cell cultures and highly porous biocompatible gelatin scaffolds. The strategy adopted exploits the peculiar differentiation potential of two distinct subsets of adult stem cells to obtain human vascularized 3D cardiac tissues. In the first step of the procedure, human mesenchymal stem cells (hMSCs) are seeded onto gelatin scaffolds to provide interconnected vessel-like structures, while human cardiomyocyte progenitor cells (hCMPCs) are stimulated in vitro to obtain their commitment toward the cardiac phenotype. The use of a modular bioreactor allows the perfusion of the whole scaffold, providing superior performance in terms of cardiac tissue maturation and cell survival. Both the cell culture on natural-derived polymers and the continuous medium perfusion of the scaffold led to the formation of a densely packaged proto-tissue composed of vascular-like and cardiac-like cells, which might complete maturation process and interconnect with native tissue upon in vivo implantation. In conclusion, the data obtained through the approach here proposed highlight the importance to provide stem cells with complementary signals in vitro able to resemble the complexity of cardiac microenvironment. PMID:24917827

  7. Adult Stem Cells and Diseases of Aging

    PubMed Central

    Boyette, Lisa B.; Tuan, Rocky S.

    2014-01-01

    Preservation of adult stem cells pools is critical for maintaining tissue homeostasis into old age. Exhaustion of adult stem cell pools as a result of deranged metabolic signaling, premature senescence as a response to oncogenic insults to the somatic genome, and other causes contribute to tissue degeneration with age. Both progeria, an extreme example of early-onset aging, and heritable longevity have provided avenues to study regulation of the aging program and its impact on adult stem cell compartments. In this review, we discuss recent findings concerning the effects of aging on stem cells, contributions of stem cells to age-related pathologies, examples of signaling pathways at work in these processes, and lessons about cellular aging gleaned from the development and refinement of cellular reprogramming technologies. We highlight emerging therapeutic approaches to manipulation of key signaling pathways corrupting or exhausting adult stem cells, as well as other approaches targeted at maintaining robust stem cell pools to extend not only lifespan but healthspan. PMID:24757526

  8. Potential of Newborn and Adult Stem Cells for the Production of Vascular Constructs Using the Living Tissue Sheet Approach

    PubMed Central

    Bourget, Jean-Michel; Gauvin, Robert; Duchesneau, David; Remy, Murielle; Auger, François A.; Germain, Lucie

    2015-01-01

    Bypass surgeries using native vessels rely on the availability of autologous veins and arteries. An alternative to those vessels could be tissue-engineered vascular constructs made by self-organized tissue sheets. This paper intends to evaluate the potential use of mesenchymal stem cells (MSCs) isolated from two different sources: (1) bone marrow-derived MSCs and (2) umbilical cord blood-derived MSCs. When cultured in vitro, a proportion of those cells differentiated into smooth muscle cell- (SMC-) like cells and expressed contraction associated proteins. Moreover, these cells assembled into manipulable tissue sheets when cultured in presence of ascorbic acid. Tubular vessels were then produced by rolling those tissue sheets on a mandrel. The architecture, contractility, and mechanical resistance of reconstructed vessels were compared with tissue-engineered media and adventitia produced from SMCs and dermal fibroblasts, respectively. Histology revealed a collagenous extracellular matrix and the contractile responses measured for these vessels were stronger than dermal fibroblasts derived constructs although weaker than SMCs-derived constructs. The burst pressure of bone marrow-derived vessels was higher than SMCs-derived ones. These results reinforce the versatility of the self-organization approach since they demonstrate that it is possible to recapitulate a contractile media layer from MSCs without the need of exogenous scaffolding material. PMID:26504783

  9. Adult Mammalian Neural Stem Cells and Neurogenesis: Five Decades Later

    PubMed Central

    Bond, Allison M.; Ming, Guo-li; Song, Hongjun

    2015-01-01

    Summary Adult somatic stem cells in various organs maintain homeostatic tissue regeneration and enhance plasticity. Since its initial discovery five decades ago, investigations of adult neurogenesis and neural stem cells have led to an established and expanding field that has significantly influenced many facets of neuroscience, developmental biology and regenerative medicine. Here we review recent progress and focus on questions related to adult mammalian neural stem cells that also apply to other somatic stem cells. We further discuss emerging topics that are guiding the field toward better understanding adult neural stem cells and ultimately applying these principles to improve human health. PMID:26431181

  10. Apoptosis, stem cells, and tissue regeneration.

    PubMed

    Bergmann, Andreas; Steller, Hermann

    2010-10-26

    Most metazoans have at least some ability to regenerate damaged cells and tissues, although the regenerative capacity varies depending on the species, organ, or developmental stage. Cell replacement and regeneration occur in two contexts: renewal of spent cells during tissue homeostasis (homeostatic growth), and in response to external injury, wounding, or amputation (epimorphic regeneration). Model organisms that display remarkable regenerative capacity include amphibians, planarians, Hydra, and the vertebrate liver. In addition, several mammalian organs--including the skin, gut, kidney, muscle, and even the human nervous system--have some ability to replace spent or damaged cells. Although the regenerative response is complex, it typically involves the induction of new cell proliferation through formation of a blastema, followed by cell specification, differentiation, and patterning. Stem cells and undifferentiated progenitor cells play an important role in both tissue homeostasis and tissue regeneration. Stem cells are typically quiescent or passing slowly through the cell cycle in adult tissues, but they can be activated in response to cell loss and wounding. A series of studies, mostly performed in Drosophila as well as in Hydra, Xenopus, and mouse, has revealed an unexpected role of apoptotic caspases in the production of mitogenic signals that stimulate the proliferation of stem and progenitor cells to aid in tissue regeneration. This Review summarizes some of the key findings and discusses links to stem cell biology and cancer.

  11. Comparison of human adult stem cells from adipose tissue and bone marrow in the treatment of experimental autoimmune encephalomyelitis

    PubMed Central

    2014-01-01

    Introduction While administration of ex vivo culture-expanded stem cells has been used to study immunosuppressive mechanisms in multiple models of autoimmune diseases, less is known about the uncultured, nonexpanded stromal vascular fraction (SVF)-based therapy. The SVF is composed of a heterogeneous population of cells and has been used clinically to treat acute and chronic diseases, alleviating symptoms in a range of tissues and organs. Methods In this study, the ability of human SVF cells was compared with culture-expanded adipose stem cells (ASCs) and bone-derived marrow stromal cells (BMSCs) as a treatment of myelin oligodendrocyte glycoprotein (35–55)-induced experimental autoimmune encephalitis in C57Bl/6J mice, a well-studied multiple sclerosis model (MS). A total of 1 × 106 BMSCs, ASCs, or SVF cells were administered intraperitoneally concomitantly with the induction of disease. Mice were monitored daily for clinical signs of disease by three independent, blinded investigators and rated on a scale of 0 to 5. Spinal cords were obtained after euthanasia at day 30 and processed for histological staining using luxol fast blue, toluidine blue, and hematoxylin and eosin to measure myelin and infiltrating immune cells. Blood was collected from mice at day 30 and analyzed by enzyme-linked immunosorbent assay to measure serum levels of inflammatory cytokines. Results The data indicate that intraperitoneal administration of all cell types significantly ameliorates the severity of disease. Furthermore, the data also demonstrate, for the first time, that the SVF was as effective as the more commonly cultured BMSCs and ASCs in an MS model. All cell therapies also demonstrated a similar reduction in tissue damage, inflammatory infiltrates, and sera levels of IFNγ and IL-12. While IFNγ levels were reduced to comparable levels between treatment groups, levels of IL-12 were significantly lower in SVF-treated than BMSC-treated or ASC-treated mice. Conclusions Based

  12. Building Epithelial Tissues from Skin Stem Cells

    PubMed Central

    Fuchs, E.; Nowak, J.A.

    2009-01-01

    The skin epidermis and its appendages provide a protective barrier that guards against loss of fluids, physical trauma, and invasion by harmful microbes. To perform these functions while confronting the harsh environs of the outside world, our body surface undergoes constant rejuvenation through homeostasis. In addition, it must be primed to repair wounds in response to injury. The adult skin maintains epidermal homeostasis, hair regeneration, and wound repair through the use of its stem cells. What are the properties of skin stem cells, when do they become established during embryogenesis, and how are they able to build tissues with such remarkably distinct architectures? How do stem cells maintain tissue homeostasis and repair wounds and how do they regulate the delicate balance between proliferation and differentiation? What is the relationship between skin cancer and mutations that perturbs the regulation of stem cells? In the past 5 years, the field of skin stem cells has bloomed as we and others have been able to purify and dissect the molecular properties of these tiny reservoirs of goliath potential. We report here progress on these fronts, with emphasis on our laboratory’s contributions to the fascinating world of skin stem cells. PMID:19022769

  13. Craniofacial Tissue Engineering by Stem Cells

    PubMed Central

    Mao, J.J.; Giannobile, W.V.; Helms, J.A.; Hollister, S.J.; Krebsbach, P.H.; Longaker, M.T.; Shi, S.

    2008-01-01

    Craniofacial tissue engineering promises the regeneration or de novo formation of dental, oral, and craniofacial structures lost to congenital anomalies, trauma, and diseases. Virtually all craniofacial structures are derivatives of mesenchymal cells. Mesenchymal stem cells are the offspring of mesenchymal cells following asymmetrical division, and reside in various craniofacial structures in the adult. Cells with characteristics of adult stem cells have been isolated from the dental pulp, the deciduous tooth, and the periodontium. Several craniofacial structures—such as the mandibular condyle, calvarial bone, cranial suture, and subcutaneous adipose tissue—have been engineered from mesenchymal stem cells, growth factor, and/or gene therapy approaches. As a departure from the reliance of current clinical practice on durable materials such as amalgam, composites, and metallic alloys, biological therapies utilize mesenchymal stem cells, delivered or internally recruited, to generate craniofacial structures in temporary scaffolding biomaterials. Craniofacial tissue engineering is likely to be realized in the foreseeable future, and represents an opportunity that dentistry cannot afford to miss. PMID:17062735

  14. Effects of Neural Stem Cell and Olfactory Ensheathing Cell Co-transplants on Tissue Remodelling After Transient Focal Cerebral Ischemia in the Adult Rat.

    PubMed

    Augestad, Ingrid Lovise; Nyman, Axel Karl Gottfrid; Costa, Alex Ignatius; Barnett, Susan Carol; Sandvig, Axel; Håberg, Asta Kristine; Sandvig, Ioanna

    2017-01-24

    Effective transplant-mediated repair of ischemic brain lesions entails extensive tissue remodeling, especially in the ischemic core. Neural stem cells (NSCs) are promising reparative candidates for stroke induced lesions, however, their survival and integration with the host-tissue post-transplantation is poor. In this study, we address this challenge by testing whether co-grafting of NSCs with olfactory ensheathing cells (OECs), a special type of glia with proven neuroprotective, immunomodulatory, and angiogenic effects, can promote graft survival and host tissue remodelling. Transient focal cerebral ischemia was induced in adult rats by a 60-min middle cerebral artery occlusion (MCAo) followed by reperfusion. Ischemic lesions were verified by neurological testing and magnetic resonance imaging. Transplantation into the globus pallidus of NSCs alone or in combination with OECs was performed at two weeks post-MCAo, followed by histological analyses at three weeks post-transplantation. We found evidence of extensive vascular remodelling in the ischemic core as well as evidence of NSC motility away from the graft and into the infarct border in severely lesioned animals co-grafted with OECs. These findings support a possible role of OECs as part of an in situ tissue engineering paradigm for transplant mediated repair of ischemic brain lesions.

  15. Comparison of gene-specific DNA methylation patterns in equine induced pluripotent stem cell lines with cells derived from equine adult and fetal tissues.

    PubMed

    Hackett, Catherine H; Greve, Line; Novakofski, Kira D; Fortier, Lisa A

    2012-07-01

    Cellular pluripotency is associated with expression of the homeobox transcription factor genes NANOG, SOX2, and POU5F1 (OCT3/4 protein). Some reports suggest that mesenchymal progenitor cells (MPCs) may express increased quantities of these genes, creating the possibility that MPCs are more "pluripotent" than other adult cell types. The objective of this study was to determine whether equine bone marrow-derived MPCs had gene expression or DNA methylation patterns that differed from either early fetal-derived or terminally differentiated adult cells. Specifically, this study compared DNA methylation of the NANOG and SOX2 promoter regions and concurrent gene expression of NANOG, SOX2, and POU5F1 in equine induced pluripotent stem (iPS) cells, fetal fibroblasts, fetal brain cells, adult chondrocytes, and MPCs. Results indicate that NANOG and POU5F1 were not detectable in appreciable quantities in tissues other than the equine iPS cell lines. Equine iPS cells expressed large quantities of all three genes examined. Significantly increased quantities of SOX2 were noted in iPS cells and both fetal-derived cell types compared with adult cells. MPCs and adult chondrocytes expressed equivalent, low quantities of SOX2. Further, NANOG and SOX2 expression inversely correlated with the DNA methylation pattern in the promoter region, such that as gene expression increased, DNA methylation decreased. The equine iPS cell lines examined demonstrated DNA methylation and gene expression patterns that were consistent with pluripotency features described in other species. Results do not support previous reports that NANOG, SOX2, and POU5F1 are poised for increased activity in MPCs compared with other adult cells.

  16. Stem cells as vehicles for youthful regeneration of aged tissues.

    PubMed

    Rando, Thomas A; Wyss-Coray, Tony

    2014-06-01

    Stem cells hold great promise for regenerative therapies for a wide spectrum of diseases and disorders of aging by virtue of their ability to regenerate tissues and contribute to their homeostasis. Aging is associated with a marked decline in these functionalities of adult stem cells. As such, regeneration of aged tissues is both less efficient and less effective than that of young tissues. Recent studies have revealed the remarkably dynamic responses of stem cells to systemic signals, including the ability of "youthful" factors in the blood of young animals to enhance the functionality of aged stem cells. Thus, there is much hope that even aged stem cells retain a remarkable regenerative potential if provided with the correct cues and environment to engage in tissue repair. The overall focus of the presentations of this session is to address the determinants of changes in stem cell functionality with age, the key characteristics of stem cells in aged tissues, the extent to which those characteristics are capable of being rejuvenated and by what signals, and the potential for stem cell therapeutics for chronic diseases and acute injuries in aged individuals.

  17. Stem cells, tissue engineering and periodontal regeneration.

    PubMed

    Han, J; Menicanin, D; Gronthos, S; Bartold, P M

    2014-06-01

    The aim of this review is to discuss the clinical utility of stem cells in periodontal regeneration by reviewing relevant literature that assesses the periodontal-regenerative potential of stem cells. We consider and describe the main stem cell populations that have been utilized with regard to periodontal regeneration, including bone marrow-derived mesenchymal stem cells and the main dental-derived mesenchymal stem cell populations: periodontal ligament stem cells, dental pulp stem cells, stem cells from human exfoliated deciduous teeth, stem cells from apical papilla and dental follicle precursor cells. Research into the use of stem cells for tissue regeneration has the potential to significantly influence periodontal treatment strategies in the future.

  18. [Stem cells and tissue engineering techniques].

    PubMed

    Sica, Gigliola

    2013-01-01

    The therapeutic use of stem cells and tissue engineering techniques are emerging in urology. Here, stem cell types, their differentiating potential and fundamental characteristics are illustrated. The cancer stem cell hypothesis is reported with reference to the role played by stem cells in the origin, development and progression of neoplastic lesions. In addition, recent reports of results obtained with stem cells alone or seeded in scaffolds to overcome problems of damaged urinary tract tissue are summarized. Among others, the application of these biotechnologies in urinary bladder, and urethra are delineated. Nevertheless, apart from the ethical concerns raised from the use of embryonic stem cells, a lot of questions need to be solved concerning the biology of stem cells before their widespread use in clinical trials. Further investigation is also required in tissue engineering utilizing animal models.

  19. Adult stem cells: hopes and hypes of regenerative medicine.

    PubMed

    Dulak, Józef; Szade, Krzysztof; Szade, Agata; Nowak, Witold; Józkowicz, Alicja

    2015-01-01

    Stem cells are self-renewing cells that can differentiate into specialized cell type(s). Pluripotent stem cells, i.e. embryonic stem cells (ESC) or induced pluripotent stem cells (iPSC) differentiate into cells of all three embryonic lineages. Multipotent stem cells, like hematopoietic stem cells (HSC), can develop into multiple specialized cells in a specific tissue. Unipotent cells differentiate only into one cell type, like e.g. satellite cells of skeletal muscle. There are many examples of successful clinical applications of stem cells. Over million patients worldwide have benefited from bone marrow transplantations performed for treatment of leukemias, anemias or immunodeficiencies. Skin stem cells are used to heal severe burns, while limbal stem cells can regenerate the damaged cornea. Pluripotent stem cells, especially the patient-specific iPSC, have a tremendous therapeutic potential, but their clinical application will require overcoming numerous drawbacks. Therefore, the use of adult stem cells, which are multipotent or unipotent, can be at present a more achievable strategy. Noteworthy, some studies ascribed particular adult stem cells as pluripotent. However, despite efforts, the postulated pluripotency of such events like "spore-like cells", "very small embryonic-like stem cells" or "multipotent adult progenitor cells" have not been confirmed in stringent independent studies. Also plasticity of the bone marrow-derived cells which were suggested to differentiate e.g. into cardiomyocytes, has not been positively verified, and their therapeutic effect, if observed, results rather from the paracrine activity. Here we discuss the examples of recent studies on adult stem cells in the light of current understanding of stem cell biology.

  20. Runx Family Genes in Tissue Stem Cell Dynamics.

    PubMed

    Wang, Chelsia Qiuxia; Mok, Michelle Meng Huang; Yokomizo, Tomomasa; Tergaonkar, Vinay; Osato, Motomi

    2017-01-01

    The Runx family genes play important roles in development and cancer, largely via their regulation of tissue stem cell behavior. Their involvement in two organs, blood and skin, is well documented. This review summarizes currently known Runx functions in the stem cells of these tissues. The fundamental core mechanism(s) mediated by Runx proteins has been sought; however, it appears that there does not exist one single common machinery that governs both tissue stem cells. Instead, Runx family genes employ multiple spatiotemporal mechanisms in regulating individual tissue stem cell populations. Such specific Runx requirements have been unveiled by a series of cell type-, developmental stage- or age-specific gene targeting studies in mice. Observations from these experiments revealed that the regulation of stem cells by Runx family genes turned out to be far more complex than previously thought. For instance, although it has been reported that Runx1 is required for the endothelial-to-hematopoietic cell transition (EHT) but not thereafter, recent studies clearly demonstrated that Runx1 is also needed during the period subsequent to EHT, namely at perinatal stage. In addition, Runx1 ablation in the embryonic skin mesenchyme eventually leads to complete loss of hair follicle stem cells (HFSCs) in the adult epithelium, suggesting that Runx1 facilitates the specification of skin epithelial stem cells in a cell extrinsic manner. Further in-depth investigation into how Runx family genes are involved in stem cell regulation is warranted.

  1. Fibroblast growth factor receptors in in vitro and in vivo chondrogenesis: relating tissue engineering using adult mesenchymal stem cells to embryonic development.

    PubMed

    Hellingman, Catharine A; Koevoet, Wendy; Kops, Nicole; Farrell, Eric; Jahr, Holger; Liu, Wei; Baatenburg de Jong, Robert J; Frenz, Dorothy A; van Osch, Gerjo J V M

    2010-02-01

    Adult mesenchymal stem cells (MSCs) are considered promising candidate cells for therapeutic cartilage and bone regeneration. Because tissue regeneration and embryonic development may involve similar pathways, understanding common pathways may lead to advances in regenerative medicine. In embryonic limb development, fibroblast growth factor receptors (FGFRs) play a role in chondrogenic differentiation. The aim of this study was to investigate and compare FGFR expression in in vivo embryonic limb development and in vitro chondrogenesis of MSCs. Our study showed that in in vitro chondrogenesis of MSCs three sequential stages can be found, as in embryonic limb development. A mesenchymal condensation (indicated by N-cadherin) is followed by chondrogenic differentiation (indicated by collagen II), and hypertrophy (indicated by collagen X). FGFR1-3 are expressed in a stage-dependent pattern during in vitro differentiation and in vivo embryonic limb development. In both models FGFR2 is clearly expressed by cells in the condensation phase. No FGFR expression was observed in differentiating and mature hyaline chondrocytes, whereas hypertrophic chondrocytes stained strongly for all FGFRs. To evaluate whether stage-specific modulation of chondrogenic differentiation in MSCs is possible with different subtypes of FGF, FGF2 and FGF9 were added to the chondrogenic medium during different stages in the culture process (early or late). FGF2 and FGF9 differentially affected the amount of cartilage formed by MSCs depending on the stage in which they were added. These results will help us understand the role of FGF signaling in chondrogenesis and find new tools to monitor and control chondrogenic differentiation.

  2. Functional liver tissue engineering by an adult mouse liver-derived neuro-glia antigen 2-expressing stem/progenitor population.

    PubMed

    Zhang, Hongyu; Siegel, Christopher T; Li, Jing; Lai, Jiejuan; Shuai, Ling; Lai, Xiangdong; Zhang, Yujun; Jiang, Yan; Bie, Ping; Bai, Lianhua

    2016-09-17

    Deaths due to end-stage liver diseases (ESLD) are increasingly registered annually in the world. Liver transplantation is the ultimate treatment for ESLD to date, which has been hampered by a critical shortage of organs. The potential of decellularized liver scaffolds (DLS) derived from solid organs as a three dimensional (3D) platform has been evolved as a promising approach in liver tissue engineering for translating functional liver organ replacements, but questions still exist regarding the optimal cell population for seeding in DLS and the preparation of the DLS themselves. The aim of our study was to utilize a sodium dodecyl sulfate (SDS) decellularization procedure in combination with a low concentration of trypsin (0.005%)-EDTA (0.002%) process to manufacture DLS from whole mouse livers and recellularized with hepatic stem/progenitors for use in liver tissue engineering and injured liver treatment. Results showed that the DLS generated with all the necessary microstructure and the extracellular components to support seeded hepatic stem/progenitor cell attachment, functional hepatic cell differentiation. Hepatic differentiation from stem/progenitor cells loaded by DLS was more efficient than that of the stem/progenitor cells in the 2D cell culture model. In summary, the method of DLS loaded by hepatic stem/progenitor cells provided by this study was effective in maintaining DLS extracellular matrix (ECM) to introduce seeded stem/progenitor cell differentiation, hepatic-like tissue formation and functional hepatic protein production in vitro that promoted functional recovery and survival in a mouse model of dimethylnitrosamine (DEN)-induced liver cirrhosis after auxiliary heterotopic liver transplantation.

  3. Expansion of Multipotent Stem Cells from the Adult Human Brain

    PubMed Central

    Murrell, Wayne; Palmero, Emily; Bianco, John; Stangeland, Biljana; Joel, Mrinal; Paulson, Linda; Thiede, Bernd; Grieg, Zanina; Ramsnes, Ingunn; Skjellegrind, Håvard K.; Nygård, Ståle; Brandal, Petter; Sandberg, Cecilie; Vik-Mo, Einar; Palmero, Sheryl; Langmoen, Iver A.

    2013-01-01

    The discovery of stem cells in the adult human brain has revealed new possible scenarios for treatment of the sick or injured brain. Both clinical use of and preclinical research on human adult neural stem cells have, however, been seriously hampered by the fact that it has been impossible to passage these cells more than a very few times and with little expansion of cell numbers. Having explored a number of alternative culturing conditions we here present an efficient method for the establishment and propagation of human brain stem cells from whatever brain tissue samples we have tried. We describe virtually unlimited expansion of an authentic stem cell phenotype. Pluripotency proteins Sox2 and Oct4 are expressed without artificial induction. For the first time multipotency of adult human brain-derived stem cells is demonstrated beyond tissue boundaries. We characterize these cells in detail in vitro including microarray and proteomic approaches. Whilst clarification of these cells’ behavior is ongoing, results so far portend well for the future repair of tissues by transplantation of an adult patient’s own-derived stem cells. PMID:23967194

  4. Growing vascularized heart tissue from stem cells.

    PubMed

    Lim, Shiang Y; Hernández, Damián; Dusting, Gregory J

    2013-08-01

    The promise of stem cells to repair the heart after damage or heart attack has not been realized because most such cells are lost after transplantation. A new approach is to grow substantial viable pieces of cardiac tissue from human stem cells by cardiac tissue engineering. Such constructs must be fully vascularized and perfused to ensure the viability of clinically relevant volumes of tissue. This requires careful choice of cells, culture conditions, a biomaterial to act as scaffold, and crucial strategies for vascularization. Autologous stem cells with high plasticity, which would avoid the need for antirejection therapies after transplantation, are an attractive source of both cardiomyocytes and vascular cells. Most stem cells also have inherent paracrine activity, releasing cytoprotective factors and growth-promoting cytokines that can further stimulate tissue regeneration and neovascularization through recruitment of endogenous stem and progenitor cells. Current advances for growing vascularized and functional cardiac constructs with human stem cells are described, bringing us a step closer to the engineering of complex cardiac tissues such as pacemaker, conducting tissue, or contractile myocardial flaps ideal for transplantation. From studies in rats successful transplantation of thin constructs to the ventricle has been reported, but there remain further issues to resolve before larger human constructs will be available to test in the clinic.

  5. Beyond the Niche: Tissue-Level Coordination of Stem Cell Dynamics

    PubMed Central

    O’Brien, Lucy Erin; Bilder, David

    2014-01-01

    Adult animals rely on populations of stem cells to ensure organ function throughout their lifetime. Stem cells are governed by signals from stem cell niches, and much is known about how single niches promote stemness and direct stem cell behavior. However, most organs contain a multitude of stem cell–niche units, which are often distributed across the entire expanse of the tissue. Beyond the biology of individual stem cell–niche interactions, the next challenge is to uncover the tissue-level processes that orchestrate spatial control of stem-based renewal, repair, and remodeling throughout a whole organ. Here we examine what is known about higher order mechanisms for interniche coordination in epithelial organs, whose simple geometry offers a promising entry point for understanding the regulation of niche number, distribution, and activity. We also consider the potential existence of stem cell territories and how tissue architecture may influence niche coordination. PMID:23937350

  6. Beyond the niche: tissue-level coordination of stem cell dynamics.

    PubMed

    O'Brien, Lucy Erin; Bilder, David

    2013-01-01

    Adult animals rely on populations of stem cells to ensure organ function throughout their lifetime. Stem cells are governed by signals from stem cell niches, and much is known about how single niches promote stemness and direct stem cell behavior. However, most organs contain a multitude of stem cell-niche units, which are often distributed across the entire expanse of the tissue. Beyond the biology of individual stem cell-niche interactions, the next challenge is to uncover the tissue-level processes that orchestrate spatial control of stem-based renewal, repair, and remodeling throughout a whole organ. Here we examine what is known about higher order mechanisms for interniche coordination in epithelial organs, whose simple geometry offers a promising entry point for understanding the regulation of niche number, distribution, and activity. We also consider the potential existence of stem cell territories and how tissue architecture may influence niche coordination.

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

    PubMed

    Cornelison, Ddw; Perdiguero, Eusebio

    2017-01-01

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

  8. Potential of adult neural stem cells in stroke therapy.

    PubMed

    Andres, Robert H; Choi, Raymond; Steinberg, Gary K; Guzman, Raphael

    2008-11-01

    Despite state-of-the-art therapy, clinical outcome after stroke remains poor, with many patients left permanently disabled and dependent on care. Stem cell therapy has evolved as a promising new therapeutic avenue for the treatment of stroke in experimental studies, and recent clinical trials have proven its feasibility and safety in patients. Replacement of damaged cells and restoration of function can be accomplished by transplantation of different cell types, such as embryonic, fetal or adult stem cells, human fetal tissue and genetically engineered cell lines. Adult neural stem cells offer the advantage of avoiding the ethical problems associated with embryonic or fetal stem cells and can be harvested as autologous grafts from the individual patients. Furthermore, stimulation of endogenous adult stem cell-mediated repair mechanisms in the brain might offer new avenues for stroke therapy without the necessity of transplantation. However, important scientific issues need to be addressed to advance our understanding of the molecular mechanisms underlying the critical steps in cell-based repair to allow the introduction of these experimental techniques into clinical practice. This review describes up-to-date experimental concepts using adult neural stem cells for the treatment of stroke.

  9. Intestinal stem cells in the adult Drosophila midgut

    SciTech Connect

    Jiang, Huaqi; Edgar, Bruce A.

    2011-11-15

    Drosophila has long been an excellent model organism for studying stem cell biology. Notably, studies of Drosophila's germline stem cells have been instrumental in developing the stem cell niche concept. The recent discovery of somatic stem cells in adult Drosophila, particularly the intestinal stem cells (ISCs) of the midgut, has established Drosophila as an exciting model to study stem cell-mediated adult tissue homeostasis and regeneration. Here, we review the major signaling pathways that regulate the self-renewal, proliferation and differentiation of Drosophila ISCs, discussing how this regulation maintains midgut homeostasis and mediates regeneration of the intestinal epithelium after injury. -- Highlights: Black-Right-Pointing-Pointer The homeostasis and regeneration of adult fly midguts are mediated by ISCs. Black-Right-Pointing-Pointer Damaged enterocytes induce the proliferation of intestinal stem cells (ISC). Black-Right-Pointing-Pointer EGFR and Jak/Stat signalings mediate compensatory ISC proliferation. Black-Right-Pointing-Pointer Notch signaling regulates ISC self-renewal and differentiation.

  10. Stem Cell Sources for Vascular Tissue Engineering and Regeneration

    PubMed Central

    Bajpai, Vivek K.

    2012-01-01

    This review focuses on the stem cell sources with the potential to be used in vascular tissue engineering and to promote vascular regeneration. The first clinical studies using tissue-engineered vascular grafts are already under way, supporting the potential of this technology in the treatment of cardiovascular and other diseases. Despite progress in engineering biomaterials with the appropriate mechanical properties and biological cues as well as bioreactors for generating the correct tissue microenvironment, the source of cells that make up the vascular tissues remains a major challenge for tissue engineers and physicians. Mature cells from the tissue of origin may be difficult to obtain and suffer from limited proliferative capacity, which may further decline as a function of donor age. On the other hand, multipotent and pluripotent stem cells have great potential to provide large numbers of autologous cells with a great differentiation capacity. Here, we discuss the adult multipotent as well as embryonic and induced pluripotent stem cells, their differentiation potential toward vascular lineages, and their use in engineering functional and implantable vascular tissues. We also discuss the associated challenges that need to be addressed in order to facilitate the transition of this technology from the bench to the bedside. PMID:22571595

  11. Recruitment of Mediator Complex by Cell Type and Stage-Specific Factors Required for Tissue-Specific TAF Dependent Gene Activation in an Adult Stem Cell Lineage

    PubMed Central

    Lu, Chenggang; Fuller, Margaret T.

    2015-01-01

    Onset of terminal differentiation in adult stem cell lineages is commonly marked by robust activation of new transcriptional programs required to make the appropriate differentiated cell type(s). In the Drosophila male germ line stem cell lineage, the switch from proliferating spermatogonia to spermatocyte is accompanied by one of the most dramatic transcriptional changes in the fly, as over 1000 new transcripts turn on in preparation for meiosis and spermatid differentiation. Here we show that function of the coactivator complex Mediator is required for activation of hundreds of new transcripts in the spermatocyte program. Mediator appears to act in a sequential hierarchy, with the testis activating Complex (tMAC), a cell type specific form of the Mip/dREAM general repressor, required to recruit Mediator subunits to the chromatin, and Mediator function required to recruit the testis TAFs (tTAFs), spermatocyte specific homologs of subunits of TFIID. Mediator, tMAC and the tTAFs co-regulate expression of a major set of spermatid differentiation genes. The Mediator subunit Med22 binds the tMAC component Topi when the two are coexpressed in S2 cells, suggesting direct recruitment. Loss of Med22 function in spermatocytes causes meiosis I maturation arrest male infertility, similar to loss of function of the tMAC subunits or the tTAFs. Our results illuminate how cell type specific versions of the Mip/dREAM complex and the general transcription machinery cooperate to drive selective gene activation during differentiation in stem cell lineages. PMID:26624996

  12. Generation of stomach tissue from mouse embryonic stem cells.

    PubMed

    Noguchi, Taka-aki K; Ninomiya, Naoto; Sekine, Mari; Komazaki, Shinji; Wang, Pi-Chao; Asashima, Makoto; Kurisaki, Akira

    2015-08-01

    Successful pluripotent stem cell differentiation methods have been developed for several endoderm-derived cells, including hepatocytes, β-cells and intestinal cells. However, stomach lineage commitment from pluripotent stem cells has remained a challenge, and only antrum specification has been demonstrated. We established a method for stomach differentiation from embryonic stem cells by inducing mesenchymal Barx1, an essential gene for in vivo stomach specification from gut endoderm. Barx1-inducing culture conditions generated stomach primordium-like spheroids, which differentiated into mature stomach tissue cells in both the corpus and antrum by three-dimensional culture. This embryonic stem cell-derived stomach tissue (e-ST) shared a similar gene expression profile with adult stomach, and secreted pepsinogen as well as gastric acid. Furthermore, TGFA overexpression in e-ST caused hypertrophic mucus and gastric anacidity, which mimicked Ménétrier disease in vitro. Thus, in vitro stomach tissue derived from pluripotent stem cells mimics in vivo development and can be used for stomach disease models.

  13. Prospect of Stem Cells in Bone Tissue Engineering: A Review

    PubMed Central

    Yousefi, Azizeh-Mitra; James, Paul F.; Akbarzadeh, Rosa; Subramanian, Aswati; Flavin, Conor; Oudadesse, Hassane

    2016-01-01

    Mesenchymal stem cells (MSCs) have been the subject of many studies in recent years, ranging from basic science that looks into MSCs properties to studies that aim for developing bioengineered tissues and organs. Adult bone marrow-derived mesenchymal stem cells (BM-MSCs) have been the focus of most studies due to the inherent potential of these cells to differentiate into various cell types. Although, the discovery of induced pluripotent stem cells (iPSCs) represents a paradigm shift in our understanding of cellular differentiation. These cells are another attractive stem cell source because of their ability to be reprogramed, allowing the generation of multiple cell types from a single cell. This paper briefly covers various types of stem cell sources that have been used for tissue engineering applications, with a focus on bone regeneration. Then, an overview of some recent studies making use of MSC-seeded 3D scaffold systems for bone tissue engineering has been presented. The emphasis has been placed on the reported scaffold properties that tend to improve MSCs adhesion, proliferation, and osteogenic differentiation outcomes. PMID:26880976

  14. Hair follicle: a novel source of multipotent stem cells for tissue engineering and regenerative medicine.

    PubMed

    Mistriotis, Panagiotis; Andreadis, Stelios T

    2013-08-01

    The adult body harbors powerful reservoirs of stem cells that enable tissue regeneration under homeostatic conditions or in response to disease or injury. The hair follicle (HF) is a readily accessible mini organ within the skin and contains stem cells from diverse developmental origins that were shown to have surprisingly broad differentiation potential. In this review, we discuss the biology of the HF with particular emphasis on the various stem cell populations residing within the tissue. We summarize the existing knowledge on putative HF stem cell markers, the differentiation potential, and technologies to isolate and expand distinct stem cell populations. We also discuss the potential of HF stem cells for drug and gene delivery, tissue engineering, and regenerative medicine. We propose that the abundance of stem cells with broad differentiation potential and the ease of accessibility makes the HF an ideal source of stem cells for gene and cell therapies.

  15. [Application prospect of adult stem cells in male infertility].

    PubMed

    Yang, Rui-Feng; Xiong, Cheng-Liang

    2013-05-01

    The study on stem cells is a hot field in biomedical science in recent years, and has furthered from laboratory to clinical application. Stem cells, according to their developmental stage and differential properties, can be divided into embryonic stem cells, induced PS cells and adult stem cells, among which, adult stem cells have already been applied to the clinical treatment of many systemic diseases. Currently, the study of spermatogonial stem cells and adult stem cells is in the front of the basic researches on the treatment of male infertility, but the time has not yet arrived for their clinical application. This paper outlines the application prospect of adult stem cells in male infertility.

  16. [Heart tissue from embryonic stem cells].

    PubMed

    Zimmermann, W-H

    2008-09-01

    Embryonic stem cells can give rise to all somatic cells, making them an attractive cell source for tissue engineering applications. The propensity of cells to form tissue-like structures in a culture dish has been well documented. We and others made use of this intrinsic property to generate bioartificial heart muscle. First proof-of-concept studies involved immature heart cells mainly from fetal chicken, neonatal rats and mice. They eventually provided evidence that force-generating heart muscle can be engineered in vitro. Recently, the focus shifted to the application of stem cells to eventually enable the generation of human heart muscle and reach following long-term goals: (1) development of a simplified in vitro model of heart muscle development; (2) generation of a human test-bed for drug screening and development; (3) allocation of surrogate heart tissue to myocardial repair applications. This overview will provide the background for cell-based myocardial repair, introduce the main myocardial tissue engineering concepts, discuss the use of embryonic and non-embryonic stem cells, and lays out the potential direct and indirect therapeutic use of human tissue engineered myocardium.

  17. Stem cell sources for clinical islet transplantation in type 1 diabetes: embryonic and adult stem cells.

    PubMed

    Miszta-Lane, Helena; Mirbolooki, Mohammadreza; James Shapiro, A M; Lakey, Jonathan R T

    2006-01-01

    Lifelong immunosuppressive therapy and inadequate sources of transplantable islets have led the islet transplantation benefits to less than 0.5% of type 1 diabetics. Whereas the potential risk of infection by animal endogenous viruses limits the uses of islet xeno-transplantation, deriving islets from stem cells seems to be able to overcome the current problems of islet shortages and immune compatibility. Both embryonic (derived from the inner cell mass of blastocysts) and adult stem cells (derived from adult tissues) have shown controversial results in secreting insulin in vitro and normalizing hyperglycemia in vivo. ESCs research is thought to have much greater developmental potential than adult stem cells; however it is still in the basic research phase. Existing ESC lines are not believed to be identical or ideal for generating islets or beta-cells and additional ESC lines have to be established. Research with ESCs derived from humans is controversial because it requires the destruction of a human embryo and/or therapeutic cloning, which some believe is a slippery slope to reproductive cloning. On the other hand, adult stem cells are already in some degree specialized, recipients may receive their own stem cells. They are flexible but they have shown mixed degree of availability. Adult stem cells are not pluripotent. They may not exist for all organs. They are difficult to purify and they cannot be maintained well outside the body. In order to draw the future avenues in this field, existent discrepancies between the results need to be clarified. In this study, we will review the different aspects and challenges of using embryonic or adult stem cells in clinical islet transplantation for the treatment of type 1 diabetes.

  18. The longest telomeres: a general signature of adult stem cell compartments

    PubMed Central

    Flores, Ignacio; Canela, Andres; Vera, Elsa; Tejera, Agueda; Cotsarelis, George; Blasco, María A.

    2008-01-01

    Identification of adult stem cells and their location (niches) is of great relevance for regenerative medicine. However, stem cell niches are still poorly defined in most adult tissues. Here, we show that the longest telomeres are a general feature of adult stem cell compartments. Using confocal telomere quantitative fluorescence in situ hybridization (telomapping), we find gradients of telomere length within tissues, with the longest telomeres mapping to the known stem cell compartments. In mouse hair follicles, we show that cells with the longest telomeres map to the known stem cell compartments, colocalize with stem cell markers, and behave as stem cells upon treatment with mitogenic stimuli. Using K15-EGFP reporter mice, which mark hair follicle stem cells, we show that GFP-positive cells have the longest telomeres. The stem cell compartments in small intestine, testis, cornea, and brain of the mouse are also enriched in cells with the longest telomeres. This constitutes the description of a novel general property of adult stem cell compartments. Finally, we make the novel finding that telomeres shorten with age in different mouse stem cell compartments, which parallels a decline in stem cell functionality, suggesting that telomere loss may contribute to stem cell dysfunction with age. PMID:18283121

  19. In situ tissue regeneration: chemoattractants for endogenous stem cell recruitment.

    PubMed

    Vanden Berg-Foels, Wendy S

    2014-02-01

    Tissue engineering uses cells, signaling molecules, and/or biomaterials to regenerate injured or diseased tissues. Ex vivo expanded mesenchymal stem cells (MSC) have long been a cornerstone of regeneration therapies; however, drawbacks that include altered signaling responses and reduced homing capacity have prompted investigation of regeneration based on endogenous MSC recruitment. Recent successful proof-of-concept studies have further motivated endogenous MSC recruitment-based approaches. Stem cell migration is required for morphogenesis and organogenesis during development and for tissue maintenance and injury repair in adults. A biomimetic approach to in situ tissue regeneration by endogenous MSC requires the orchestration of three main stages: MSC recruitment, MSC differentiation, and neotissue maturation. The first stage must result in recruitment of a sufficient number of MSC, capable of effecting regeneration, to the injured or diseased tissue. One of the challenges for engineering endogenous MSC recruitment is the selection of effective chemoattractant(s). The objective of this review is to synthesize and evaluate evidence of recruitment efficacy by reported chemoattractants, including growth factors, chemokines, and other more recently appreciated MSC chemoattractants. The influence of MSC tissue sources, cell culture methods, and the in vitro and in vivo environments is discussed. This growing body of knowledge will serve as a basis for the rational design of regenerative therapies based on endogenous MSC recruitment. Successful endogenous MSC recruitment is the first step of successful tissue regeneration.

  20. Stem cell-based meniscus tissue engineering.

    PubMed

    Mandal, Biman B; Park, Sang-Hyug; Gil, Eun Seok; Kaplan, David L

    2011-11-01

    Knee meniscus, a fibrocartilaginous tissue, is characterized by heterogeneity in extracellular matrix (ECM) and biomechanical properties, and critical for orthopedic stability, load transmission, shock absorption, and stress distribution within the knee joint. Most damage to the meniscus cannot be effectively healed by the body due to its partial avascular nature; thus, damage caused by injury or age impairs normal knee function, predisposing patients to osteoarthritis. Meniscus tissue engineering offers a possible solution to this problem by generating replacement tissue that may be implanted into the defect site to mimic the function of natural meniscal tissue. To address this need, a multiporous, multilamellar meniscus was formed using silk protein scaffolds and stem cells. The silk scaffolds were seeded with human bone marrow stem cells and differentiated over time in chondrogenic culture in the presence of transforming growth factor-beta 3 to generate meniscus-like tissue in vitro. High cellularity along with abundant ECM leading to enhanced biomechanics similar to native tissue was found. Higher levels of collagen type I and II, sulfated glycosaminoglycans along with enhanced collagen 1-α1, aggrecan, and SOX9 gene expression further confirmed differentiation and matured cell phenotype. The results of this study are a step forward toward biomechanically competent meniscus engineering, reconstituting both form and function of the native meniscus.

  1. Adult stem cells and their ability to differentiate.

    PubMed

    Tarnowski, Maciej; Sieron, Aleksander L

    2006-08-01

    This is a review of the current status of knowledge on adult stem cells as well as the criteria and evidence for their potential to transform into different cell types and cell lineages. Reports on stem cell sources, focusing on tissues from adult subjects, were also investigated. Numerous reports have been published on the search for early markers of both stem cells and the precursors of various cell lineages. The question is still open about the characteristics of the primary stem cell. The existing proofs and hypotheses have not yielded final solutions to this problem. From a practical point of view it is also crucial to find a minimal set of markers determining the phenotypes of the precursor cells of a particular cell lineage. Several lines of evidence seem to bring closer the day when we will be able to detect the right stem cell niche and successfully isolate precursor cells that are needed for the treatment of a particular disorder. Recent reports on cases of cancer in patients subjected to stem cell therapy are yet another controversial issue looked into in this review, although the pros and cons emerging from the results of published studies still do not provide satisfying evidence to fully understand this issue.

  2. Adherent neural stem (NS) cells from fetal and adult forebrain.

    PubMed

    Pollard, Steven M; Conti, Luciano; Sun, Yirui; Goffredo, Donato; Smith, Austin

    2006-07-01

    Stable in vitro propagation of central nervous system (CNS) stem cells would offer expanded opportunities to dissect basic molecular, cellular, and developmental processes and to model neurodegenerative disease. CNS stem cells could also provide a source of material for drug discovery assays and cell replacement therapies. We have recently reported the generation of adherent, symmetrically expandable, neural stem (NS) cell lines derived both from mouse and human embryonic stem cells and from fetal forebrain (Conti L, Pollard SM, Gorba T, Reitano E, Toselli M, Biella G, Sun Y, Sanzone S, Ying QL, Cattaneo E, Smith A. 2005. Niche-independent symmetrical self-renewal of a mammalian tissue stem cell. PLoS Biol 3(9):e283). These NS cells retain neuronal and glial differentiation potential after prolonged passaging and are transplantable. NS cells are likely to comprise the resident stem cell population within heterogeneous neurosphere cultures. Here we demonstrate that similar NS cell cultures can be established from the adult mouse brain. We also characterize the growth factor requirements for NS cell derivation and self-renewal. We discuss our current understanding of the relationship of NS cell lines to physiological progenitor cells of fetal and adult CNS.

  3. Generating intestinal tissue from stem cells: potential for research and therapy

    PubMed Central

    Howell, Jonathan C; Wells, James M

    2011-01-01

    Intestinal resection and malformations in adult and pediatric patients result in devastating consequences. Unfortunately, allogeneic transplantation of intestinal tissue into patients has not been met with the same measure of success as the transplantation of other organs. Attempts to engineer intestinal tissue in vitro include disaggregation of adult rat intestine into subunits called organoids, harvesting native adult stem cells from mouse intestine and spontaneous generation of intestinal tissue from embryoid bodies. Recently, by utilizing principles gained from the study of developmental biology, human pluripotent stem cells have been demonstrated to be capable of directed differentiation into intestinal tissue in vitro. Pluripotent stem cells offer a unique and promising means to generate intestinal tissue for the purposes of modeling intestinal disease, understanding embryonic development and providing a source of material for therapeutic transplantation. PMID:22050526

  4. The less-often-traveled surface of stem cells: caveolin-1 and caveolae in stem cells, tissue repair and regeneration

    PubMed Central

    2013-01-01

    Stem cells are an important resource for tissue repair and regeneration. While a great deal of attention has focused on derivation and molecular regulation of stem cells, relatively little research has focused on how the subcellular structure and composition of the cell membrane influences stem cell activities such as proliferation, differentiation and homing. Caveolae are specialized membrane lipid rafts coated with caveolin scaffolding proteins, which can regulate cholesterol transport and the activity of cell signaling receptors and their downstream effectors. Caveolin-1 is involved in the regulation of many cellular processes, including growth, control of mitochondrial antioxidant levels, migration and senescence. These activities are of relevance to stem cell biology, and in this review evidence for caveolin-1 involvement in stem cell biology is summarized. Altered stem and progenitor cell populations in caveolin-1 null mice suggest that caveolin-1 can regulate stem cell proliferation, and in vitro studies with isolated stem cells suggest that caveolin-1 regulates stem cell differentiation. The available evidence leads us to hypothesize that caveolin-1 expression may stabilize the differentiated and undifferentiated stem cell phenotype, and transient downregulation of caveolin-1 expression may be required for transition between the two. Such regulation would probably be critical in regenerative applications of adult stem cells and during tissue regeneration. We also review here the temporal changes in caveolin-1 expression reported during tissue repair. Delayed muscle regeneration in transgenic mice overexpressing caveolin-1 as well as compromised cardiac, brain and liver tissue repair and delayed wound healing in caveolin-1 null mice suggest that caveolin-1 plays an important role in tissue repair, but that this role may be negative or positive depending on the tissue type and the nature of the repair process. Finally, we also discuss how caveolin-1

  5. Coculture with embryonic stem cells improves neural differentiation of adipose tissue-derived stem cells.

    PubMed

    Bahmani, L; Taha, M F; Javeri, A

    2014-07-11

    Embryonic stem (ES) cells secrete some soluble factors which may affect the differentiation potential of adult stem cells toward different lineages. In the present study, we evaluated neural differentiation of mouse adipose tissue-derived stem cells (ADSCs) following coculture with ES cells. For this purpose, ADSCs were induced in a medium supplemented with a synthetic serum replacement and various concentrations of retinoic acid (RA). Then, third-passaged ADSCs were indirectly cocultured with ES cells, and the expression levels of pluripotency markers, OCT4 and Sox2, mesenchymal stem cell markers, CD73 and CD105, and proliferating cell nuclear antigen (PCNA), were assessed in the cocultured ADSCs. Moreover, the control and cocultured ADSCs were differentiated with or without RA treatment. We showed here that 2-week differentiated ADSCs expressed several neuron-specific genes, and RA treatment improved neural differentiation of the ADSCs. The expression levels of OCT4, Sox2 and PCNA were upregulated in the cocultured ADSCs. Moreover, coculture with the ES cells significantly improved neural differentiation of the ADSCs. Treatment of the cocultured ADSCs with RA diminished the expression of neural maturation markers. Coculture with the ES cells efficiently improves neural differentiation of the ADSCs. Non-contact coculture with the ES cells may be used as an efficient strategy to improve differentiation potential of adult stem cells for developmental studies and regenerative medicine.

  6. Translational research of adult stem cell therapy.

    PubMed

    Suzuki, Gen

    2015-11-26

    Congestive heart failure (CHF) secondary to chronic coronary artery disease is a major cause of morbidity and mortality world-wide. Its prevalence is increasing despite advances in medical and device therapies. Cell based therapies generating new cardiomyocytes and vessels have emerged as a promising treatment to reverse functional deterioration and prevent the progression to CHF. Functional efficacy of progenitor cells isolated from the bone marrow and the heart have been evaluated in preclinical large animal models. Furthermore, several clinical trials using autologous and allogeneic stem cells and progenitor cells have demonstrated their safety in humans yet their clinical relevance is inconclusive. This review will discuss the clinical therapeutic applications of three specific adult stem cells that have shown particularly promising regenerative effects in preclinical studies, bone marrow derived mesenchymal stem cell, heart derived cardiosphere-derived cell and cardiac stem cell. We will also discuss future therapeutic approaches.

  7. Stem Cell-Mediated Regeneration of the Adult Brain

    PubMed Central

    Jessberger, Sebastian

    2016-01-01

    Acute or chronic injury of the adult mammalian brain is often associated with persistent functional deficits as its potential for regeneration and capacity to rebuild lost neural structures is limited. However, the discovery that neural stem cells (NSCs) persist throughout life in discrete regions of the brain, novel approaches to induce the formation of neuronal and glial cells, and recently developed strategies to generate tissue for exogenous cell replacement strategies opened novel perspectives how to regenerate the adult brain. Here, we will review recently developed approaches for brain repair and discuss future perspectives that may eventually allow for developing novel treatment strategies in acute and chronic brain injury. PMID:27781019

  8. Adipose Tissue-Derived Stem Cells in Regenerative Medicine

    PubMed Central

    Frese, Laura; Dijkman, Petra E.; Hoerstrup, Simon P.

    2016-01-01

    In regenerative medicine, adult stem cells are the most promising cell types for cell-based therapies. As a new source for multipotent stem cells, human adipose tissue has been introduced. These so called adipose tissue-derived stem cells (ADSCs) are considered to be ideal for application in regenerative therapies. Their main advantage over mesenchymal stem cells derived from other sources, e.g. from bone marrow, is that they can be easily and repeatable harvested using minimally invasive techniques with low morbidity. ADSCs are multipotent and can differentiate into various cell types of the tri-germ lineages, including e.g. osteocytes, adipocytes, neural cells, vascular endothelial cells, cardiomyocytes, pancreatic β-cells, and hepatocytes. Interestingly, ADSCs are characterized by immunosuppressive properties and low immunogenicity. Their secretion of trophic factors enforces the therapeutic and regenerative outcome in a wide range of applications. Taken together, these particular attributes of ADSCs make them highly relevant for clinical applications. Consequently, the therapeutic potential of ADSCs is enormous. Therefore, this review will provide a brief overview of the possible therapeutic applications of ADSCs with regard to their differentiation potential into the tri-germ lineages. Moreover, the relevant advancements made in the field, regulatory aspects as well as other challenges and obstacles will be highlighted. PMID:27721702

  9. Adipose Tissue-Derived Stem Cells in Regenerative Medicine.

    PubMed

    Frese, Laura; Dijkman, Petra E; Hoerstrup, Simon P

    2016-07-01

    In regenerative medicine, adult stem cells are the most promising cell types for cell-based therapies. As a new source for multipotent stem cells, human adipose tissue has been introduced. These so called adipose tissue-derived stem cells (ADSCs) are considered to be ideal for application in regenerative therapies. Their main advantage over mesenchymal stem cells derived from other sources, e.g. from bone marrow, is that they can be easily and repeatable harvested using minimally invasive techniques with low morbidity. ADSCs are multipotent and can differentiate into various cell types of the tri-germ lineages, including e.g. osteocytes, adipocytes, neural cells, vascular endothelial cells, cardiomyocytes, pancreatic β-cells, and hepatocytes. Interestingly, ADSCs are characterized by immunosuppressive properties and low immunogenicity. Their secretion of trophic factors enforces the therapeutic and regenerative outcome in a wide range of applications. Taken together, these particular attributes of ADSCs make them highly relevant for clinical applications. Consequently, the therapeutic potential of ADSCs is enormous. Therefore, this review will provide a brief overview of the possible therapeutic applications of ADSCs with regard to their differentiation potential into the tri-germ lineages. Moreover, the relevant advancements made in the field, regulatory aspects as well as other challenges and obstacles will be highlighted.

  10. Adult stem cells underlying lung regeneration.

    PubMed

    Xian, Wa; McKeon, Frank

    2012-03-01

    Despite the massive toll in human suffering imparted by degenerative lung disease, including COPD, idiopathic pulmonary fibrosis and ARDS, the scientific community has been surprisingly agnostic regarding the potential of lung tissue, and in particular the alveoli, to regenerate. However, there is circumstantial evidence in humans and direct evidence in mice that ARDS triggers robust regeneration of lung tissue rather than irreversible fibrosis. The stem cells responsible for this remarkable regenerative process has garnered tremendous attention, most recently yielding a defined set of cloned human airway stem cells marked by p63 expression but with distinct commitment to differentiated cell types typical of the upper or lower airways, the latter of which include alveoli-like structures in vitro and in vivo. These recent advances in lung regeneration and distal airway stem cells and the potential of associated soluble factors in regeneration must be harnessed for therapeutic options in chronic lung disease.

  11. Generation of pluripotent stem cells from adult human testis.

    PubMed

    Conrad, Sabine; Renninger, Markus; Hennenlotter, Jörg; Wiesner, Tina; Just, Lothar; Bonin, Michael; Aicher, Wilhelm; Bühring, Hans-Jörg; Mattheus, Ulrich; Mack, Andreas; Wagner, Hans-Joachim; Minger, Stephen; Matzkies, Matthias; Reppel, Michael; Hescheler, Jürgen; Sievert, Karl-Dietrich; Stenzl, Arnulf; Skutella, Thomas

    2008-11-20

    Human primordial germ cells and mouse neonatal and adult germline stem cells are pluripotent and show similar properties to embryonic stem cells. Here we report the successful establishment of human adult germline stem cells derived from spermatogonial cells of adult human testis. Cellular and molecular characterization of these cells revealed many similarities to human embryonic stem cells, and the germline stem cells produced teratomas after transplantation into immunodeficient mice. The human adult germline stem cells differentiated into various types of somatic cells of all three germ layers when grown under conditions used to induce the differentiation of human embryonic stem cells. We conclude that the generation of human adult germline stem cells from testicular biopsies may provide simple and non-controversial access to individual cell-based therapy without the ethical and immunological problems associated with human embryonic stem cells.

  12. Adult Stem Cell Therapy for Stroke: Challenges and Progress

    PubMed Central

    Bang, Oh Young; Kim, Eun Hee; Cha, Jae Min; Moon, Gyeong Joon

    2016-01-01

    Stroke is one of the leading causes of death and physical disability among adults. It has been 15 years since clinical trials of stem cell therapy in patients with stroke have been conducted using adult stem cells like mesenchymal stem cells and bone marrow mononuclear cells. Results of randomized controlled trials showed that adult stem cell therapy was safe but its efficacy was modest, underscoring the need for new stem cell therapy strategies. The primary limitations of current stem cell therapies include (a) the limited source of engraftable stem cells, (b) the presence of optimal time window for stem cell therapies, (c) inherited limitation of stem cells in terms of growth, trophic support, and differentiation potential, and (d) possible transplanted cell-mediated adverse effects, such as tumor formation. Here, we discuss recent advances that overcome these hurdles in adult stem cell therapy for stroke. PMID:27733032

  13. Adipose-derived stem cells for periodontal tissue regeneration.

    PubMed

    Tobita, Morikuni; Mizuno, Hiroshi

    2011-01-01

    Mesenchymal stem cells can effectively regenerate destroyed periodontal tissue. Because periodontal tissues are complex, mesenchymal stem cells that can differentiate into many tissue types would aid periodontal tissue regeneration. Indeed, periodontal tissue regeneration using mesenchymal stem cells derived from adipose tissue or bone marrow has been performed in experimental animal models, such as rat, canine, swine, and monkey. We have shown that rat periodontal tissue can be regenerated with adipose-derived stem cells. Adipose tissue contains a large number of stromal cells and is relatively easy to obtain in large quantities, and thus constitutes a very convenient stromal cell source. In this chapter, we introduce a rat periodontal tissue regeneration model using adipose-derived stem cells.

  14. Nano scaffolds and stem cell therapy in liver tissue engineering

    NASA Astrophysics Data System (ADS)

    Montaser, Laila M.; Fawzy, Sherin M.

    2015-08-01

    Tissue engineering and regenerative medicine have been constantly developing of late due to the major progress in cell and organ transplantation, as well as advances in materials science and engineering. Although stem cells hold great potential for the treatment of many injuries and degenerative diseases, several obstacles must be overcome before their therapeutic application can be realized. These include the development of advanced techniques to understand and control functions of micro environmental signals and novel methods to track and guide transplanted stem cells. A major complication encountered with stem cell therapies has been the failure of injected cells to engraft to target tissues. The application of nanotechnology to stem cell biology would be able to address those challenges. Combinations of stem cell therapy and nanotechnology in tissue engineering and regenerative medicine have achieved significant advances. These combinations allow nanotechnology to engineer scaffolds with various features to control stem cell fate decisions. Fabrication of Nano fiber cell scaffolds onto which stem cells can adhere and spread, forming a niche-like microenvironment which can guide stem cells to proceed to heal damaged tissues. In this paper, current and emergent approach based on stem cells in the field of liver tissue engineering is presented for specific application. The combination of stem cells and tissue engineering opens new perspectives in tissue regeneration for stem cell therapy because of the potential to control stem cell behavior with the physical and chemical characteristics of the engineered scaffold environment.

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

    PubMed Central

    Adam, Rene C.; Fuchs, Elaine

    2015-01-01

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

  16. Sox10(+) adult stem cells contribute to biomaterial encapsulation and microvascularization.

    PubMed

    Wang, Dong; Wang, Aijun; Wu, Fan; Qiu, Xuefeng; Li, Ye; Chu, Julia; Huang, Wen-Chin; Xu, Kang; Gong, Xiaohua; Li, Song

    2017-01-10

    Implanted biomaterials and biomedical devices generally induce foreign body reaction and end up with encapsulation by a dense avascular fibrous layer enriched in extracellular matrix. Fibroblasts/myofibroblasts are thought to be the major cell type involved in encapsulation, but it is unclear whether and how stem cells contribute to this process. Here we show, for the first time, that Sox10(+) adult stem cells contribute to both encapsulation and microvessel formation. Sox10(+) adult stem cells were found sparsely in the stroma of subcutaneous loose connective tissues. Upon subcutaneous biomaterial implantation, Sox10(+) stem cells were activated and recruited to the biomaterial scaffold, and differentiated into fibroblasts and then myofibroblasts. This differentiation process from Sox10(+) stem cells to myofibroblasts could be recapitulated in vitro. On the other hand, Sox10(+) stem cells could differentiate into perivascular cells to stabilize newly formed microvessels. Sox10(+) stem cells and endothelial cells in three-dimensional co-culture self-assembled into microvessels, and platelet-derived growth factor had chemotactic effect on Sox10(+) stem cells. Transplanted Sox10(+) stem cells differentiated into smooth muscle cells to stabilize functional microvessels. These findings demonstrate the critical role of adult stem cells in tissue remodeling and unravel the complexity of stem cell fate determination.

  17. Sox10+ adult stem cells contribute to biomaterial encapsulation and microvascularization

    PubMed Central

    Wang, Dong; Wang, Aijun; Wu, Fan; Qiu, Xuefeng; Li, Ye; Chu, Julia; Huang, Wen-Chin; Xu, Kang; Gong, Xiaohua; Li, Song

    2017-01-01

    Implanted biomaterials and biomedical devices generally induce foreign body reaction and end up with encapsulation by a dense avascular fibrous layer enriched in extracellular matrix. Fibroblasts/myofibroblasts are thought to be the major cell type involved in encapsulation, but it is unclear whether and how stem cells contribute to this process. Here we show, for the first time, that Sox10+ adult stem cells contribute to both encapsulation and microvessel formation. Sox10+ adult stem cells were found sparsely in the stroma of subcutaneous loose connective tissues. Upon subcutaneous biomaterial implantation, Sox10+ stem cells were activated and recruited to the biomaterial scaffold, and differentiated into fibroblasts and then myofibroblasts. This differentiation process from Sox10+ stem cells to myofibroblasts could be recapitulated in vitro. On the other hand, Sox10+ stem cells could differentiate into perivascular cells to stabilize newly formed microvessels. Sox10+ stem cells and endothelial cells in three-dimensional co-culture self-assembled into microvessels, and platelet-derived growth factor had chemotactic effect on Sox10+ stem cells. Transplanted Sox10+ stem cells differentiated into smooth muscle cells to stabilize functional microvessels. These findings demonstrate the critical role of adult stem cells in tissue remodeling and unravel the complexity of stem cell fate determination. PMID:28071739

  18. Adult stem cel diferentiation and trafficking and their implications in disease.

    PubMed

    Zhuge, Ying; Liu, Zhao-Jun; Velazquez, Omaida C

    2010-01-01

    Stem cells are unspecialized precursor cells that mainly reside in the bone marrow and have important roles in the establishment of embryonic tissue. They also have critical functions during adulthood, where they replenish short-lived mature effector cells and regeneration of injured tissue. They have three main characteristics: self-renewal, differentiation and homeostatic control. In order to maintain a pool of stem cells that support the production of blood cells, stromal elements and connective tissue, stem cells must be able to constantly replenish their own number. They must also possess the ability to differentiate and give rise to a heterogeneous group of functional cells. Finally, stem cells must possess the ability to modulate and balance differentiation and self-renewal according to environmental stimuli and whole-organ needs to prevent the production of excessive number of effector cells.(1) In addition to formation of these cells, regulated movement of stem cells is critical for organogenesis, homeostasis and repair in adulthood. Stem cells require specific inputs from particular environments in order to perform their various functions. Some similar trafficking mechanisms are shared by leukocytes, adult and fetal stem cells, as well as cancer stem cells.(1,2) Achieving proper trafficking of stem cells will allow increased efficiency of targeted cell therapy and drug delivery.(2) In addition, understanding similarities and differences in homing and migration of malignant cancer stem cells will also clarify molecular events of tumor progression and metastasis.(2) This chapter focuses on the differentiation, trafficking and homing of the major types of adult bone marrow stem cells: hematopoietic stem cells (HSCs), mesenchymal stem cells (MSCs) and endothelial progenitor cells (EPCs) and the term"stem cell" will refer to "adult stem cells" unless otherwise specified.

  19. Oct4 expression in adult human stem cells: evidence in support of the stem cell theory of carcinogenesis.

    PubMed

    Tai, Mei-Hui; Chang, Chia-Cheng; Kiupel, Matti; Webster, Joshua D; Olson, L Karl; Trosko, James E

    2005-02-01

    The Oct3/4 gene, a POU family transcription factor, has been noted as being specifically expressed in embryonic stem cells and in tumor cells but not in cells of differentiated tissues. With the ability to isolate adult human stem cells it became possible to test for the expression of Oct3/4 gene in adult stem cells and to test the stem cell theory of carcinogenesis. Using antibodies and PCR primers we tested human breast, liver, pancreas, kidney, mesenchyme and gastric stem cells, the cancer cell lines HeLa and MCF-7 and human, dog and rat tumors for Oct4 expression. The results indicate that adult human stem cells, immortalized non-tumorigenic cells and tumor cells and cell lines, but not differentiated cells, express Oct4. Oct4 is expressed in a few cells found in the basal layer of human skin epidermis. The data demonstrate that adult stem cells maintain expression of Oct4, consistent with the stem cell hypothesis of carcinogenesis.

  20. Mesenchymal stem cells in the dental tissues: perspectives for tissue regeneration.

    PubMed

    Estrela, Carlos; Alencar, Ana Helena Gonçalves de; Kitten, Gregory Thomas; Vencio, Eneida Franco; Gava, Elisandra

    2011-01-01

    In recent years, stem cell research has grown exponentially owing to the recognition that stem cell-based therapies have the potential to improve the life of patients with conditions that range from Alzheimer's disease to cardiac ischemia and regenerative medicine, like bone or tooth loss. Based on their ability to rescue and/or repair injured tissue and partially restore organ function, multiple types of stem/progenitor cells have been speculated. Growing evidence demonstrates that stem cells are primarily found in niches and that certain tissues contain more stem cells than others. Among these tissues, the dental tissues are considered a rich source of mesenchymal stem cells that are suitable for tissue engineering applications. It is known that these stem cells have the potential to differentiate into several cell types, including odontoblasts, neural progenitors, osteoblasts, chondrocytes, and adipocytes. In dentistry, stem cell biology and tissue engineering are of great interest since may provide an innovative for generation of clinical material and/or tissue regeneration. Mesenchymal stem cells were demonstrated in dental tissues, including dental pulp, periodontal ligament, dental papilla, and dental follicle. These stem cells can be isolated and grown under defined tissue culture conditions, and are potential cells for use in tissue engineering, including, dental tissue, nerves and bone regeneration. More recently, another source of stem cell has been successfully generated from human somatic cells into a pluripotent stage, the induced pluripotent stem cells (iPS cells), allowing creation of patient- and disease-specific stem cells. Collectively, the multipotency, high proliferation rates, and accessibility make the dental stem cell an attractive source of mesenchymal stem cells for tissue regeneration. This review describes new findings in the field of dental stem cell research and on their potential use in the tissue regeneration.

  1. Adult stem cells in neural repair: Current options, limitations and perspectives.

    PubMed

    Mariano, Eric Domingos; Teixeira, Manoel Jacobsen; Marie, Suely Kazue Nagahashi; Lepski, Guilherme

    2015-03-26

    Stem cells represent a promising step for the future of regenerative medicine. As they are able to differentiate into any cell type, tissue or organ, these cells are great candidates for treatments against the worst diseases that defy doctors and researchers around the world. Stem cells can be divided into three main groups: (1) embryonic stem cells; (2) fetal stem cells; and (3) adult stem cells. In terms of their capacity for proliferation, stem cells are also classified as totipotent, pluripotent or multipotent. Adult stem cells, also known as somatic cells, are found in various regions of the adult organism, such as bone marrow, skin, eyes, viscera and brain. They can differentiate into unipotent cells of the residing tissue, generally for the purpose of repair. These cells represent an excellent choice in regenerative medicine, every patient can be a donor of adult stem cells to provide a more customized and efficient therapy against various diseases, in other words, they allow the opportunity of autologous transplantation. But in order to start clinical trials and achieve great results, we need to understand how these cells interact with the host tissue, how they can manipulate or be manipulated by the microenvironment where they will be transplanted and for how long they can maintain their multipotent state to provide a full regeneration.

  2. Neurodevelopment. Live imaging of adult neural stem cell behavior in the intact and injured zebrafish brain.

    PubMed

    Barbosa, Joana S; Sanchez-Gonzalez, Rosario; Di Giaimo, Rossella; Baumgart, Emily Violette; Theis, Fabian J; Götz, Magdalena; Ninkovic, Jovica

    2015-05-15

    Adult neural stem cells are the source for restoring injured brain tissue. We used repetitive imaging to follow single stem cells in the intact and injured adult zebrafish telencephalon in vivo and found that neurons are generated by both direct conversions of stem cells into postmitotic neurons and via intermediate progenitors amplifying the neuronal output. We observed an imbalance of direct conversion consuming the stem cells and asymmetric and symmetric self-renewing divisions, leading to depletion of stem cells over time. After brain injury, neuronal progenitors are recruited to the injury site. These progenitors are generated by symmetric divisions that deplete the pool of stem cells, a mode of neurogenesis absent in the intact telencephalon. Our analysis revealed changes in the behavior of stem cells underlying generation of additional neurons during regeneration.

  3. Stem cell-delivery therapeutics for periodontal tissue regeneration.

    PubMed

    Chen, Fa-Ming; Sun, Hai-Hua; Lu, Hong; Yu, Qing

    2012-09-01

    Periodontitis, an inflammatory disease, is the most common cause of tooth loss in adults. Attempts to regenerate the complex system of tooth-supporting apparatus (i.e., the periodontal ligament, alveolar bone and root cementum) after loss/damage due to periodontitis have made some progress recently and provide a useful experimental model for the evaluation of future regenerative therapies. Concentrated efforts have now moved from the use of guided tissue/bone regeneration technology, a variety of growth factors and various bone grafts/substitutes toward the design and practice of endogenous regenerative technology by recruitment of host cells (cell homing) or stem cell-based therapeutics by transplantation of outside cells to enhance periodontal tissue regeneration and its biomechanical integration. This shift is driven by the general inability of conventional therapies to deliver satisfactory outcomes, particularly in cases where the disease has caused large tissue defects in the periodontium. Cell homing and cell transplantation are both scientifically meritorious approaches that show promise to completely and reliably reconstitute all tissue and connections damaged through periodontal disease, and hence research into both directions should continue. In view of periodontal regeneration by paradigms that unlock the body's innate regenerative potential has been reviewed elsewhere, this paper specifically explores and analyses the stem cell types and cell delivery strategies that have been or have the potential to be used as therapeutics in periodontal regenerative medicine, with particular emphasis placed on the efficacy and safety concerns of current stem cell-based periodontal therapies that may eventually enter into the clinic.

  4. Adipose-derived adult stem cells: available technologies for potential clinical regenerative applications in dentistry.

    PubMed

    Catalano, Enrico; Cochis, Andrea; Varoni, Elena; Rimondini, Lia; Carrassi, Antonio; Azzimonti, Barbara

    2013-01-01

    Tissue homeostasis depends closely on the activity and welfare of adult stem cells. These cells represent a promising tool for biomedical research since they can aid in treatment and promote the regeneration of damaged organs in many human disorders. Adult stem cells indefinitely preserve their ability to self-renew and differentiate into various phenotypes; this capacity could be promoted in vitro by particular culture conditions (differentiation media) or spontaneously induced in vivo by exploiting the biochemical and mechanical properties of the tissue in which the stem cells are implanted. Among the different sources of adult stem cells, adipose tissue is an attractive possibility thanks to its ready availability and the standard extraction techniques at our disposal today. This review discusses the isolation, characterization, and differentiation of human adipose-derived adult stem cells, as well as regeneration strategies, therapeutic uses, and adverse effects of their delivery. In particular, since oral disorders (e.g., trauma, erosion, and chronic periodontitis) often cause the loss of dental tissue along with functional, phonetic, and aesthetic impairment, this review focuses on the application of human adipose-derived adult stem cells, alone or in combination with biomaterials, in treating oral diseases.

  5. Pre-transplantation specification of stem cells to cardiac lineage for regeneration of cardiac tissue.

    PubMed

    Mayorga, Maritza; Finan, Amanda; Penn, Marc

    2009-03-01

    Myocardial infarction (MI) is a lead cause of mortality in the Western world. Treatment of acute MI is focused on restoration of antegrade flow which inhibits further tissue loss, but does not restore function to damaged tissue. Chronic therapy for injured myocardial tissue involves medical therapy that attempts to minimize pathologic remodeling of the heart. End stage therapy for chronic heart failure (CHF) involves inotropic therapy to increase surviving cardiac myocyte function or mechanical augmentation of cardiac performance. Not until the point of heart transplantation, a limited resource at best, does therapy focus on the fundamental problem of needing to replace injured tissue with new contractile tissue. In this setting, the potential for stem cell therapy has garnered significant interest for its potential to regenerate or create new contractile cardiac tissue. While to date adult stem cell therapy in clinical trials has suggested potential benefit, there is waning belief that the approaches used to date lead to regeneration of cardiac tissue. As the literature has better defined the pathways involved in cardiac differentiation, preclinical studies have suggested that stem cell pretreatment to direct stem cell differentiation prior to stem cell transplantation may be a more efficacious strategy for inducing cardiac regeneration. Here we review the available literature on pre-transplantation conditioning of stem cells in an attempt to better understand stem cell behavior and their readiness in cell-based therapy for myocardial regeneration.

  6. Transcriptional profiling of adult neural stem-like cells from the human brain.

    PubMed

    Sandberg, Cecilie Jonsgar; Vik-Mo, Einar O; Behnan, Jinan; Helseth, Eirik; Langmoen, Iver A

    2014-01-01

    There is a great potential for the development of new cell replacement strategies based on adult human neural stem-like cells. However, little is known about the hierarchy of cells and the unique molecular properties of stem- and progenitor cells of the nervous system. Stem cells from the adult human brain can be propagated and expanded in vitro as free floating neurospheres that are capable of self-renewal and differentiation into all three cell types of the central nervous system. Here we report the first global gene expression study of adult human neural stem-like cells originating from five human subventricular zone biopsies (mean age 42, range 33-60). Compared to adult human brain tissue, we identified 1,189 genes that were significantly up- and down-regulated in adult human neural stem-like cells (1% false discovery rate). We found that adult human neural stem-like cells express stem cell markers and have reduced levels of markers that are typical of the mature cells in the nervous system. We report that the genes being highly expressed in adult human neural stem-like cells are associated with developmental processes and the extracellular region of the cell. The calcium signaling pathway and neuroactive ligand-receptor interactions are enriched among the most differentially regulated genes between adult human neural stem-like cells and adult human brain tissue. We confirmed the expression of 10 of the most up-regulated genes in adult human neural stem-like cells in an additional sample set that included adult human neural stem-like cells (n = 6), foetal human neural stem cells (n = 1) and human brain tissues (n = 12). The NGFR, SLITRK6 and KCNS3 receptors were further investigated by immunofluorescence and shown to be heterogeneously expressed in spheres. These receptors could potentially serve as new markers for the identification and characterisation of neural stem- and progenitor cells or as targets for manipulation of cellular fate.

  7. Concise review: The plasticity of stem cell niches: a general property behind tissue homeostasis and repair.

    PubMed

    Rojas-Ríos, Patricia; González-Reyes, Acaimo

    2014-04-01

    Stem cell activity is tightly regulated during development and in adult tissues through the combined action of local and systemic effectors. While stem cells and their microenvironments are capable of sustaining homeostasis in normal physiological circumstances, they also provide host tissues with a remarkable plasticity to respond to perturbations. Here, we review recent discoveries that shed light on the adaptive response of niches to systemic signals and aging, and on the ability of niches to modulate signaling upon local perturbations. These characteristics of stem cells and their niches give organs an essential advantage to deal with aging, injury or pathological conditions.

  8. Epimorphic regeneration approach to tissue replacement in adult mammals.

    PubMed

    Agrawal, Vineet; Johnson, Scott A; Reing, Janet; Zhang, Li; Tottey, Stephen; Wang, Gang; Hirschi, Karen K; Braunhut, Susan; Gudas, Lorraine J; Badylak, Stephen F

    2010-02-23

    Urodeles and fetal mammals are capable of impressive epimorphic regeneration in a variety of tissues, whereas the typical default response to injury in adult mammals consists of inflammation and scar tissue formation. One component of epimorphic regeneration is the recruitment of resident progenitor and stem cells to a site of injury. Bioactive molecules resulting from degradation of extracellular matrix (ECM) have been shown to recruit a variety of progenitor and stem cells in vitro in adult mammals. The ability to recruit multipotential cells to the site of injury by in vivo administration of chemotactic ECM degradation products in a mammalian model of digit amputation was investigated in the present study. Adult, 6- to 8-week-old C57/BL6 mice were subjected to midsecond phalanx amputation of the third digit of the right hind foot and either treated with chemotactic ECM degradation products or left untreated. At 14 days after amputation, mice treated with ECM degradation products showed an accumulation of heterogeneous cells that expressed markers of multipotency, including Sox2, Sca1, and Rex1 (Zfp42). Cells isolated from the site of amputation were capable of differentiation along neuroectodermal and mesodermal lineages, whereas cells isolated from control mice were capable of differentiation along only mesodermal lineages. The present findings demonstrate the recruitment of endogenous stem cells to a site of injury, and/or their generation/proliferation therein, in response to ECM degradation products.

  9. Stem Cells and Scaffolds for Vascularizing Engineered Tissue Constructs

    NASA Astrophysics Data System (ADS)

    Luong, E.; Gerecht, S.

    The clinical impact of tissue engineering depends upon our ability to direct cells to form tissues with characteristic structural and mechanical properties from the molecular level up to organized tissue. Induction and creation of functional vascular networks has been one of the main goals of tissue engineering either in vitro, for the transplantation of prevascularized constructs, or in vivo, for cellular organization within the implantation site. In most cases, tissue engineering attempts to recapitulate certain aspects of normal development in order to stimulate cell differentiation and functional tissue assembly. The induction of tissue growth generally involves the use of biodegradable and bioactive materials designed, ideally, to provide a mechanical, physical, and biochemical template for tissue regeneration. Human embryonic stem cells (hESCs), derived from the inner cell mass of a developing blastocyst, are capable of differentiating into all cell types of the body. Specifically, hESCs have the capability to differentiate and form blood vessels de novo in a process called vasculogenesis. Human ESC-derived endothelial progenitor cells (EPCs) and endothelial cells have substantial potential for microvessel formation, in vitro and in vivo. Human adult EPCs are being isolated to understand the fundamental biology of how these cells are regulated as a population and to explore whether these cells can be differentiated and reimplanted as a cellular therapy in order to arrest or even reverse damaged vasculature. This chapter focuses on advances made toward the generation and engineering of functional vascular tissue, focusing on both the scaffolds - the synthetic and biopolymer materials - and the cell sources - hESCs and hEPCs.

  10. Novel Adult Stem Cells for Peripheral Nerve Regeneration

    DTIC Science & Technology

    2012-09-01

    Circulation 103, 882–888 (2001). 52. Biernaskie, J. et al. SKPs derive from hair follicle precursors and exhibit properties of adult dermal stem cells...3). * indicates significant difference between indicated groups using Holm’s t- test . (P < 0.01). (l–s) Immunostaining of isolated sm-mHC − cells...and the tissue from which the cells were derived using student’s t- test (P < 0.05). † indicates significant difference between inferior vena cava and

  11. Transplanted human embryonic stem cells as biological 'catalysts' for tissue repair and regeneration.

    PubMed

    Heng, Boon Chin; Liu, Hua; Cao, Tong

    2005-01-01

    Human embryonic stem cells have tremendous potential in the newly emerging field of regenerative medicine. Recently, it was demonstrated that the rescue of lethal cardiac defects in Id knockout mutant mouse embryos was not due to the transplanted cells giving rise to functional new tissues within the defective embryonic heart. Instead, there is indirect evidence that the observed therapeutic effect was due to various secreted factors emanating from the transplanted cells. This therefore, introduces the exciting prospect of utilizing human embryonic stem cells as biological 'catalysts' to promote tissue repair and regeneration in transplantation therapy. However, the immunological barrier against allogenic transplantation, as well as the teratogenic potential of human embryonic stem cells poses major technical challenges. A possible strategy to overcome the immunological barrier may be to impose a temporary regimen of immunosuppressive drugs followed by their gradual withdrawal, once adequate tissue regeneration has been achieved. Other more novel alternatives include the use of microencapsulation to block interaction with the transplant recipient's immune system, and co-transplantation with bone marrow-derived mesenchymal stem cells, which have been demonstrated to possess immuno-suppressive properties. The teratogenic potential of human embryonic stem cells could possibly be alleviated by directing the differentiation of these cells to specific lineages prior to transplantation, or through mitotic inactivation (gamma irradiation or mitomycin C exposure). Co-transplantation with autologous adult stem cells may represent a novel strategy to further enhance the 'catalytic' effects of human embryonic stem cells. The various factors secreted by human embryonic stem cells could then have a concentrated localized effect on relatively large numbers of co-transplanted autologous adult stem cells, which may in turn lead to enhanced repair and regeneration of the damaged

  12. 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

  13. Lin-28 promotes symmetric stem cell division and drives adaptive growth in the adult Drosophila intestine.

    PubMed

    Chen, Ching-Huan; Luhur, Arthur; Sokol, Nicholas

    2015-10-15

    Stem cells switch between asymmetric and symmetric division to expand in number as tissues grow during development and in response to environmental changes. The stem cell intrinsic proteins controlling this switch are largely unknown, but one candidate is the Lin-28 pluripotency factor. A conserved RNA-binding protein that is downregulated in most animals as they develop from embryos to adults, Lin-28 persists in populations of adult stem cells. Its function in these cells has not been previously characterized. Here, we report that Lin-28 is highly enriched in adult intestinal stem cells in the Drosophila intestine. lin-28 null mutants are homozygous viable but display defects in this population of cells, which fail to undergo a characteristic food-triggered expansion in number and have reduced rates of symmetric division as well as reduced insulin signaling. Immunoprecipitation of Lin-28-bound mRNAs identified Insulin-like Receptor (InR), forced expression of which completely rescues lin-28-associated defects in intestinal stem cell number and division pattern. Furthermore, this stem cell activity of lin-28 is independent of one well-known lin-28 target, the microRNA let-7, which has limited expression in the intestinal epithelium. These results identify Lin-28 as a stem cell intrinsic factor that boosts insulin signaling in intestinal progenitor cells and promotes their symmetric division in response to nutrients, defining a mechanism through which Lin-28 controls the adult stem cell division patterns that underlie tissue homeostasis and regeneration.

  14. Stem cells for regenerative medicine: advances in the engineering of tissues and organs

    NASA Astrophysics Data System (ADS)

    Ringe, Jochen; Kaps, Christian; Burmester, Gerd-Rüdiger; Sittinger, Michael

    2002-07-01

    The adult bone marrow stroma contains a subset of nonhematopoietic cells referred to as mesenchymal stem or mesenchymal progenitor cells (MSC). These cells have the capacity to undergo extensive replication in an undifferentiated state ex vivo. In addition, MSC have the potential to develop either in vitro or in vivo into distinct mesenchymal tissues, including bone, cartilage, fat, tendon, muscle, and marrow stroma, which suggest these cells as an attractive cell source for tissue engineering approaches. The interest in modern biological technologies such as tissue engineering has dramatically increased since it is feasible to isolate living, healthy cells from the body, expand them under cell culture conditions, combine them with biocompatible carrier materials and retransplant them into patients. Therefore, tissue engineering gives the opportunity to generate living substitutes for tissues and organs, which may overcome the drawbacks of classical tissue reconstruction: lacking quality and quantity of autologous grafts, immunogenicity of allogenic grafts and loosening of alloplastic implants. Due to the prerequisite for tissue engineering to ensure a sufficient number of tissue specific cells without donor site morbidity, much attention has been drawn to multipotential progenitor cells such as embryonic stem cells, periosteal cells and mesenchymal stem cells. In this report we review the state of the art in tissue engineering with mesenchymal stem and mesenchymal progenitor cells with emphasis on bone and cartilage reconstruction. Furthermore, several issues of importance, especially with regard to the clinical application of mesenchymal stem cells, are discussed.

  15. Debra-mediated Ci degradation controls tissue homeostasis in Drosophila adult midgut.

    PubMed

    Li, Zhouhua; Guo, Yueqin; Han, Lili; Zhang, Yan; Shi, Lai; Huang, Xudong; Lin, Xinhua

    2014-02-11

    Adult tissue homeostasis is maintained by resident stem cells and their progeny. However, the underlying mechanisms that control tissue homeostasis are not fully understood. Here, we demonstrate that Debra-mediated Ci degradation is important for intestinal stem cell (ISC) proliferation in Drosophila adult midgut. Debra inhibition leads to increased ISC activity and tissue homeostasis loss, phenocopying defects observed in aging flies. These defects can be suppressed by depleting Ci, suggesting that increased Hedgehog (Hh) signaling contributes to ISC proliferation and tissue homeostasis loss. Consistently, Hh signaling activation causes the same defects, whereas depletion of Hh signaling suppresses these defects. Furthermore, the Hh ligand from multiple sources is involved in ISC proliferation and tissue homeostasis. Finally, we show that the JNK pathway acts downstream of Hh signaling to regulate ISC proliferation. Together, our results provide insights into the mechanisms of stem cell proliferation and tissue homeostasis control.

  16. Tissue Engineering Functional Gastrointestinal Regions: The Importance of Stem and Progenitor Cells.

    PubMed

    Trecartin, Andrew; Grikscheit, Tracy

    2017-03-20

    The intestine shows extraordinary regenerative potential that might be harnessed to alleviate numerous morbid and lethal human diseases. The intestinal stem cells regenerate the epithelium every 5 days throughout an individual's lifetime. Understanding stem-cell signaling affords power to influence the niche environment for growing intestine. The manifold approaches to tissue engineering may be organized by variations of three basic components required for the transplantation and growth of stem/progenitor cells: (1) cell delivery materials or scaffolds; (2) donor cells including adult stem cells, induced pluripotent stem cells, and in vitro expansion of isolated or cocultured epithelial, smooth muscle, myofibroblasts, or nerve cells; and (3) environmental modulators or biopharmaceuticals. Tissue engineering has been applied to the regeneration of every major region of the gastrointestinal tract from esophagus to colon, with scientists around the world aiming to carry these techniques into human therapy.

  17. Stem cell technology using bioceramics: hard tissue regeneration towards clinical application.

    PubMed

    Ohnishi, Hiroe; Oda, Yasuaki; Ohgushi, Hajime

    2010-02-01

    Mesenchymal stem cells (MSCs) are adult stem cells which show differentiation capabilities toward various cell lineages. We have already used MSCs for treatments of osteoarthritis, bone necrosis and bone tumor. For this purpose, culture expanded MSCs were combined with various ceramics and then implanted. Because of rejection response to allogeneic MSC implantation, we have utilized patients' own MSCs for the treatment. Bone marrow is a good cell source of MSCs, although the MSCs also exist in adipose tissue. When comparing osteogenic differentiation of these MSCs, bone marrow MSCs show more extensive bone forming capability than adipose MSCs. Thus, the bone marrow MSCs are useful for bone tissue regeneration. However, the MSCs show limited proliferation and differentiation capabilities that hindered clinical applications in some cases. Recent advances reveal that transduction of plural transcription factors into human adult cells results in generation of new type of stem cells called induced pluripotent stem cells (iPS cells). A drawback of the iPS cells for clinical applications is tumor formation after their in vivo implantation; therefore it is difficult to use iPS cells for the treatment. To circumvent the problem, we transduced a single factor of either SOX2 or NANOG into the MSCs and found high proliferation as well as osteogenic differentiation capabilities of the MSCs. The stem cells could be combined with bioceramics for clinical applications. Here, we summarize our recent technologies using adult stem cells in viewpoints of bone tissue regeneration.

  18. TOPICAL REVIEW: Stem cell technology using bioceramics: hard tissue regeneration towards clinical application

    NASA Astrophysics Data System (ADS)

    Ohnishi, Hiroe; Oda, Yasuaki; Ohgushi, Hajime

    2010-02-01

    Mesenchymal stem cells (MSCs) are adult stem cells which show differentiation capabilities toward various cell lineages. We have already used MSCs for treatments of osteoarthritis, bone necrosis and bone tumor. For this purpose, culture expanded MSCs were combined with various ceramics and then implanted. Because of rejection response to allogeneic MSC implantation, we have utilized patients' own MSCs for the treatment. Bone marrow is a good cell source of MSCs, although the MSCs also exist in adipose tissue. When comparing osteogenic differentiation of these MSCs, bone marrow MSCs show more extensive bone forming capability than adipose MSCs. Thus, the bone marrow MSCs are useful for bone tissue regeneration. However, the MSCs show limited proliferation and differentiation capabilities that hindered clinical applications in some cases. Recent advances reveal that transduction of plural transcription factors into human adult cells results in generation of new type of stem cells called induced pluripotent stem cells (iPS cells). A drawback of the iPS cells for clinical applications is tumor formation after their in vivo implantation; therefore it is difficult to use iPS cells for the treatment. To circumvent the problem, we transduced a single factor of either SOX2 or NANOG into the MSCs and found high proliferation as well as osteogenic differentiation capabilities of the MSCs. The stem cells could be combined with bioceramics for clinical applications. Here, we summarize our recent technologies using adult stem cells in viewpoints of bone tissue regeneration.

  19. Adipose tissue-derived stem cells show considerable promise for regenerative medicine applications.

    PubMed

    Harasymiak-Krzyżanowska, Izabela; Niedojadło, Alicja; Karwat, Jolanta; Kotuła, Lidia; Gil-Kulik, Paulina; Sawiuk, Magdalena; Kocki, Janusz

    2013-12-01

    The stromal-vascular cell fraction (SVF) of adipose tissue can be an abundant source of both multipotent and pluripotent stem cells, known as adipose-derived stem cells or adipose tissue-derived stromal cells (ADSCs). The SVF also contains vascular cells, targeted progenitor cells, and preadipocytes. Stromal cells isolated from adipose tissue express common surface antigens, show the ability to adhere to plastic, and produce forms that resemble fibroblasts. They are characterized by a high proliferation potential and the ability to differentiate into cells of meso-, ecto- and endodermal origin. Although stem cells obtained from an adult organism have smaller capabilities for differentiation in comparison to embryonic and induced pluripotent stem cells (iPSs), the cost of obtaining them is significantly lower. The 40 years of research that mainly focused on the potential of bone marrow stem cells (BMSCs) revealed a number of negative factors: the painful sampling procedure, frequent complications, and small cell yield. The number of stem cells in adipose tissue is relatively large, and obtaining them is less invasive. Sampling through simple procedures such as liposuction performed under local anesthesia is less painful, ensuring patient comfort. The isolated cells are easily grown in culture, and they retain their properties over many passages. That is why adipose tissue has recently been treated as an attractive alternative source of stem cells. Essential aspects of ADSC biology and their use in regenerative medicine will be analyzed in this article.

  20. Adipose-derived stem cells and periodontal tissue engineering.

    PubMed

    Tobita, Morikuni; Mizuno, Hiroshi

    2013-01-01

    Innovative developments in the multidisciplinary field of tissue engineering have yielded various implementation strategies and the possibility of functional tissue regeneration. Technologic advances in the combination of stem cells, biomaterials, and growth factors have created unique opportunities to fabricate tissues in vivo and in vitro. The therapeutic potential of human multipotent mesenchymal stem cells (MSCs), which are harvested from bone marrow and adipose tissue, has generated increasing interest in a wide variety of biomedical disciplines. These cells can differentiate into a variety of tissue types, including bone, cartilage, fat, and nerve tissue. Adipose-derived stem cells have some advantages compared with other sources of stem cells, most notably that a large number of cells can be easily and quickly isolated from adipose tissue. In current clinical therapy for periodontal tissue regeneration, several methods have been developed and applied either alone or in combination, such as enamel matrix proteins, guided tissue regeneration, autologous/allogeneic/xenogeneic bone grafts, and growth factors. However, there are various limitations and shortcomings for periodontal tissue regeneration using current methods. Recently, periodontal tissue regeneration using MSCs has been examined in some animal models. This method has potential in the regeneration of functional periodontal tissues because the various secreted growth factors from MSCs might not only promote the regeneration of periodontal tissue but also encourage neovascularization of the damaged tissues. Adipose-derived stem cells are especially effective for neovascularization compared with other MSC sources. In this review, the possibility and potential of adipose-derived stem cells for regenerative medicine are introduced. Of particular interest, periodontal tissue regeneration with adipose-derived stem cells is discussed.

  1. zebraflash transgenic lines for in vivo bioluminescence imaging of stem cells and regeneration in adult zebrafish.

    PubMed

    Chen, Chen-Hui; Durand, Ellen; Wang, Jinhu; Zon, Leonard I; Poss, Kenneth D

    2013-12-01

    The zebrafish has become a standard model system for stem cell and tissue regeneration research, based on powerful genetics, high tissue regenerative capacity and low maintenance costs. Yet, these studies can be challenged by current limitations of tissue visualization techniques in adult animals. Here we describe new imaging methodology and present several ubiquitous and tissue-specific luciferase-based transgenic lines, which we have termed zebraflash, that facilitate the assessment of regeneration and engraftment in freely moving adult zebrafish. We show that luciferase-based live imaging reliably estimates muscle quantity in an internal organ, the heart, and can longitudinally follow cardiac regeneration in individual animals after major injury. Furthermore, luciferase-based detection enables visualization and quantification of engraftment in live recipients of transplanted hematopoietic stem cell progeny, with advantages in sensitivity and gross spatial resolution over fluorescence detection. Our findings present a versatile resource for monitoring and dissecting vertebrate stem cell and regeneration biology.

  2. Regulation of Breast Cancer Stem Cells by Tissue Rigidity

    DTIC Science & Technology

    2015-06-01

    AD ____________ __ Award Number: W81XWH-13-1-0133 TITLE: Regulation of Breast Cancer Stem Cells by Tissue Rigidity PRINCIPAL INVESTIGATOR: Adam J...CONTRACT NUMBER Regulation of Breast Cancer Stem Cell by Tissue Rigidity W81XWH-13-1-0133 Sb. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR...in breast tumors is associated with a 1 0-50-fold increase in tissue stiffness and correlates with distant metastasis and poor outcome. Recent studies

  3. Regulation of Breast Cancer Stem Cell by Tissue Rigidity

    DTIC Science & Technology

    2015-06-01

    AD_________________ Award Number: W81XWH-13-1-0132 TITLE: Regulation of Breast Cancer Stem Cell by Tissue Rigidity PRINCIPAL INVESTIGATOR: Jing...COVERED 4. TITLE AND SUBTITLE Regulation of Breast Cancer Stem Cell by Tissue Rigidity 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...fibrotic focus in breast tumors is associated with a 10-50-fold increase in tissue stiffness and correlates with distant metastasis and poor outcome. Recent

  4. Bone Marrow Stromal Stem Cells in Tissue Engineering and Regenerative Medicine.

    PubMed

    Polymeri, A; Giannobile, W V; Kaigler, D

    2016-11-01

    Bone marrow stromal stem cells (BMSCs) are adult multipotent cells, which have the potential to differentiate into cell types of mesodermal origin, namely osteocytes, adipocytes, and chondrocytes. Due to their accessibility and expansion potential, BMSCs have historically held therapeutic promise in tissue engineering and regenerative medicine applications. More recently, it has been demonstrated that not only can bone marrow stromal stem cells directly participate in tissue regeneration, but they also have the capacity to migrate to distant sites of tissue injury, where they can participate in tissue repair either directly through their differentiation or indirectly through paracrine mechanisms. Additionally, they can elicit various immunomodulatory signals, which can attenuate the inflammatory and immune responses. As such, bone marrow stromal stem cells have been explored clinically for treatment of a wide variety of different conditions including bone defects, graft-vs.-host disease, cardiovascular diseases, autoimmune diseases, diabetes, neurological diseases, and liver and kidney diseases. This review provides an overview of current clinical applications of bone marrow stromal stem cells and discusses their therapeutic properties, while also addressing limitations of their use. PubMed, Ovid, and Google Scholar online databases were searched using several keywords, including "stem cells", "tissue engineering", tissue regeneration" and "clinical trials". Additionally, Clinical trials.gov was used to locate completed clinical trials using bone marrow derived stem cells.

  5. Biomedical Application of Dental Tissue-Derived Induced Pluripotent Stem Cells.

    PubMed

    Lee, Jung-Hwan; Seo, Seog-Jin

    2016-01-01

    The academic researches and clinical applications in recent years found interest in induced pluripotent stem cells (iPSCs-) based regenerative medicine due to their pluripotency able to differentiate into any cell types in the body without using embryo. However, it is limited in generating iPSCs from adult somatic cells and use of these cells due to the low stem cell potency and donor site morbidity. In biomedical applications, particularly, dental tissue-derived iPSCs have been getting attention as a type of alternative sources for regenerating damaged tissues due to high potential of stem cell characteristics, easy accessibility and attainment, and their ectomesenchymal origin, which allow them to have potential for nerve, vessel, and dental tissue regeneration. This paper will cover the overview of dental tissue-derived iPSCs and their application with their advantages and drawbacks.

  6. Biomedical Application of Dental Tissue-Derived Induced Pluripotent Stem Cells

    PubMed Central

    Lee, Jung-Hwan; Seo, Seog-Jin

    2016-01-01

    The academic researches and clinical applications in recent years found interest in induced pluripotent stem cells (iPSCs-) based regenerative medicine due to their pluripotency able to differentiate into any cell types in the body without using embryo. However, it is limited in generating iPSCs from adult somatic cells and use of these cells due to the low stem cell potency and donor site morbidity. In biomedical applications, particularly, dental tissue-derived iPSCs have been getting attention as a type of alternative sources for regenerating damaged tissues due to high potential of stem cell characteristics, easy accessibility and attainment, and their ectomesenchymal origin, which allow them to have potential for nerve, vessel, and dental tissue regeneration. This paper will cover the overview of dental tissue-derived iPSCs and their application with their advantages and drawbacks. PMID:26989423

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

    PubMed

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

    2013-01-01

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

  8. Skin Tissue Engineering: Application of Adipose-Derived Stem Cells

    PubMed Central

    Zimoch, Jakub; Biedermann, Thomas

    2017-01-01

    Perception of the adipose tissue has changed dramatically over the last few decades. Identification of adipose-derived stem cells (ASCs) ultimately transformed paradigm of this tissue from a passive energy depot into a promising stem cell source with properties of self-renewal and multipotential differentiation. As compared to bone marrow-derived stem cells (BMSCs), ASCs are more easily accessible and their isolation yields higher amount of stem cells. Therefore, the ASCs are of high interest for stem cell-based therapies and skin tissue engineering. Currently, freshly isolated stromal vascular fraction (SVF), which may be used directly without any expansion, was also assessed to be highly effective in treating skin radiation injuries, burns, or nonhealing wounds such as diabetic ulcers. In this paper, we review the characteristics of SVF and ASCs and the efficacy of their treatment for skin injuries and disorders. PMID:28337463

  9. Microfluidic systems for stem cell-based neural tissue engineering.

    PubMed

    Karimi, Mahdi; Bahrami, Sajad; Mirshekari, Hamed; Basri, Seyed Masoud Moosavi; Nik, Amirala Bakhshian; Aref, Amir R; Akbari, Mohsen; Hamblin, Michael R

    2016-07-05

    Neural tissue engineering aims at developing novel approaches for the treatment of diseases of the nervous system, by providing a permissive environment for the growth and differentiation of neural cells. Three-dimensional (3D) cell culture systems provide a closer biomimetic environment, and promote better cell differentiation and improved cell function, than could be achieved by conventional two-dimensional (2D) culture systems. With the recent advances in the discovery and introduction of different types of stem cells for tissue engineering, microfluidic platforms have provided an improved microenvironment for the 3D-culture of stem cells. Microfluidic systems can provide more precise control over the spatiotemporal distribution of chemical and physical cues at the cellular level compared to traditional systems. Various microsystems have been designed and fabricated for the purpose of neural tissue engineering. Enhanced neural migration and differentiation, and monitoring of these processes, as well as understanding the behavior of stem cells and their microenvironment have been obtained through application of different microfluidic-based stem cell culture and tissue engineering techniques. As the technology advances it may be possible to construct a "brain-on-a-chip". In this review, we describe the basics of stem cells and tissue engineering as well as microfluidics-based tissue engineering approaches. We review recent testing of various microfluidic approaches for stem cell-based neural tissue engineering.

  10. In Vitro Spermatogenesis in Explanted Adult Mouse Testis Tissues.

    PubMed

    Sato, Takuya; Katagiri, Kumiko; Kojima, Kazuaki; Komeya, Mitsuru; Yao, Masahiro; Ogawa, Takehiko

    2015-01-01

    Research on in vitro spermatogenesis is important for elucidating the spermatogenic mechanism. We previously developed an organ culture method which can support spermatogenesis from spermatogonial stem cells up to sperm formation using immature mouse testis tissues. In this study, we examined whether it is also applicable to mature testis tissues of adult mice. We used two lines of transgenic mice, Acrosin-GFP and Gsg2-GFP, which carry the marker GFP gene specific for meiotic and haploid cells, respectively. Testis tissue fragments of adult GFP mice, aged from 4 to 29 weeks old, which express GFP at full extension, were cultured in medium supplemented with 10% KSR or AlbuMAX. GFP expression decreased rapidly and became the lowest at 7 to 14 days of culture, but then slightly increased during the following culture period. This increase reflected de novo spermatogenesis, confirmed by BrdU labeling in spermatocytes and spermatids. We also used vitamin A-deficient mice, whose testes contain only spermatogonia. The testes of those mice at 13-21 weeks old, showing no GFP expression at explantation, gained GFP expression during culturing, and spermatogenesis was confirmed histologically. In addition, the adult testis tissues of Sl/Sld mutant mice, which lack spermatogenesis due to Kit ligand mutation, were cultured with recombinant Kit ligand to induce spermatogenesis up to haploid formation. Although the efficiency of spermatogenesis was lower than that of pup, present results showed that the organ culture method is effective for the culturing of mature adult mouse testis tissue, demonstrated by the induction of spermatogenesis from spermatogonia to haploid cells.

  11. In Vitro Differentiation of Embryonic and Adult Stem Cells into Hepatocytes: State of the Art

    PubMed Central

    Snykers, Sarah; De Kock, Joery; Rogiers, Vera; Vanhaecke, Tamara

    2009-01-01

    Stem cells are a unique source of self-renewing cells within the human body. Before the end of the last millennium, adult stem cells, in contrast to their embryonic counterparts, were considered to be lineage-restricted cells or incapable of crossing lineage boundaries. However, the unique breakthrough of muscle and liver regeneration by adult bone marrow stem cells at the end of the 1990s ended this long-standing paradigm. Since then, the number of articles reporting the existence of multipotent stem cells in skin, neuronal tissue, adipose tissue, and bone marrow has escalated, giving rise, both in vivo and in vitro, to cell types other than their tissue of origin. The phenomenon of fate reprogrammation and phenotypic diversification remains, though, an enigmatic and rare process. Understanding how to control both proliferation and differentiation of stem cells and their progeny is a challenge in many fields, going from preclinical drug discovery and development to clinical therapy. In this review, we focus on current strategies to differentiate embryonic, mesenchymal(-like), and liver stem/progenitor cells into hepatocytes in vitro. Special attention is paid to intracellular and extracellular signaling, genetic modification, and cell-cell and cell-matrix interactions. In addition, some recommendations are proposed to standardize, optimize, and enrich the in vitro production of hepatocyte-like cells out of stem/progenitor cells. PMID:19056906

  12. Utilizing stem cells for three-dimensional neural tissue engineering.

    PubMed

    Knowlton, Stephanie; Cho, Yongku; Li, Xue-Jun; Khademhosseini, Ali; Tasoglu, Savas

    2016-05-26

    Three-dimensional neural tissue engineering has made great strides in developing neural disease models and replacement tissues for patients. However, the need for biomimetic tissue models and effective patient therapies remains unmet. The recent push to expand 2D neural tissue engineering into the third dimension shows great potential to advance the field. Another area which has much to offer to neural tissue engineering is stem cell research. Stem cells are well known for their self-renewal and differentiation potential and have been shown to give rise to tissues with structural and functional properties mimicking natural organs. Application of these capabilities to 3D neural tissue engineering may be highly useful for basic research on neural tissue structure and function, engineering disease models, designing tissues for drug development, and generating replacement tissues with a patient's genetic makeup. Here, we discuss the vast potential, as well as the current challenges, unique to integration of 3D fabrication strategies and stem cells into neural tissue engineering. We also present some of the most significant recent achievements, including nerve guidance conduits to facilitate better healing of nerve injuries, functional 3D biomimetic neural tissue models, physiologically relevant disease models for research purposes, and rapid and effective screening of potential drugs.

  13. Isolating stromal stem cells from periodontal granulation tissues.

    PubMed

    Hung, Tzu-Yuan; Lin, Hsiang-Chun; Chan, Ying-Jen; Yuan, Kuo

    2012-08-01

    Stem cell therapy is a promising area in regenerative medicine. Periodontal granulation tissues are often discarded during conventional surgery. If stromal stem cells can be isolated from these tissues, they can be used for subsequent surgery on the same patient. Fifteen human periodontal granulation tissue samples were obtained from intrabony defects during surgery. Immunohistochemistry (IHC) was carried out on five of the samples to identify STRO-1, a marker of mesenchymal stem cells. Five samples underwent flow cytometry analysis for the same marker. The remaining five samples were characterized by "colony formation unit-fibroblast" (CFU-f) assay and selected for proliferation assay, flow cytometry of stem cell markers, immunocytochemistry (ICC), multipotent differentiation assays, and repairing critical-size defects in mice. The ratio of STRO-1(+) cells detected by IHC was 5.91 ± 1.50%. The analysis of flow cytometry for STRO-1 was 6.70 ± 0.81%. Approximately two thirds of the CFU-f colonies had a strong reaction to STRO-1 in ICC staining. The cells were multipotent both in vitro and in vivo. Mice given bone grafts and stem cells showed significantly better bone healing than those without stem cells. Multipotent stromal stem cells can be isolated from human periodontal granulation tissues. These cells improve new bone formation when transplanted in mouse calvarial defects. Isolating stem cells from relatively accessible sites without extra procedures is clinically advantageous. This study demonstrated that human periodontal granulation tissues contain isolatable multipotent stem cells. The cells may be a good source for autotransplantation in subsequent treatment.

  14. How Somatic Adult Tissues Develop Organizer Activity.

    PubMed

    Vogg, Matthias C; Wenger, Yvan; Galliot, Brigitte

    2016-01-01

    The growth and patterning of anatomical structures from specific cellular fields in developing organisms relies on organizing centers that instruct surrounding cells to modify their behavior, namely migration, proliferation, and differentiation. We discuss here how organizers can form in adult organisms, a process of utmost interest for regenerative medicine. Animals like Hydra and planarians, which maintain their shape and fitness thanks to a highly dynamic homeostasis, offer a useful paradigm to study adult organizers in steady-state conditions. Beside the homeostatic context, these model systems also offer the possibility to study how organizers form de novo from somatic adult tissues. Both extracellular matrix remodeling and caspase activation play a key role in this transition, acting as promoters of organizer formation in the vicinity of the wound. Their respective roles and the crosstalk between them just start to be deciphered.

  15. The role of DNA damage repair in aging of adult stem cells.

    PubMed

    Kenyon, Jonathan; Gerson, Stanton L

    2007-01-01

    DNA repair maintains genomic stability and the loss of DNA repair capacity results in genetic instability that may lead to a decline of cellular function. Adult stem cells are extremely important in the long-term maintenance of tissues throughout life. They regenerate and renew tissues in response to damage and replace senescent terminally differentiated cells that no longer function. Oxidative stress, toxic byproducts, reduced mitochondrial function and external exposures all damage DNA through base modification or mis-incorporation and result in DNA damage. As in most cells, this damage may limit the survival of the stem cell population affecting tissue regeneration and even longevity. This review examines the hypothesis that an age-related loss of DNA damage repair pathways poses a significant threat to stem cell survival and longevity. Normal stem cells appear to have strict control of gene expression and DNA replication whereas stem cells with loss of DNA repair may have altered patterns of proliferation, quiescence and differentiation. Furthermore, stem cells with loss of DNA repair may be susceptible to malignant transformation either directly or through the emergence of cancer-prone stem cells. Human diseases and animal models of loss of DNA repair provide longitudinal analysis of DNA repair processes in stem cell populations and may provide links to the physiology of aging.

  16. Myocardial regeneration potential of adipose tissue-derived stem cells

    SciTech Connect

    Bai, Xiaowen; Alt, Eckhard

    2010-10-22

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

  17. Immune physiology and oogenesis in fetal and adult humans, ovarian infertility, and totipotency of adult ovarian stem cells.

    PubMed

    Bukovsky, Antonin; Caudle, Michael R; Virant-Klun, Irma; Gupta, Satish K; Dominguez, Roberto; Svetlikova, Marta; Xu, Fei

    2009-03-01

    It is still widely believed that while oocytes in invertebrates and lower vertebrates are periodically renewed throughout life, oocytes in humans and higher vertebrates are formed only during the fetal/perinatal period. However, this dogma is questioned, and clashes with Darwinian evolutionary theory. Studies of oogenesis and follicular renewal from ovarian stem cells (OSCs) in adult human ovaries, and of the role of third-party bone marrow-derived cells (monocyte-derived tissue macrophages and T lymphocytes) could help provide a better understanding of the causes of ovarian infertility, its prevention, and potential treatment. We have reported differentiation of distinct cell types from OSC and the production of new eggs in cultures derived from premenopausal and postmenopausal human ovaries. OSCs are also capable of producing neural/neuronal cells in vitro after sequential stimulation with sex steroid combinations. Hence, OSC represent a unique type of totipotent adult stem cells, which could be utilized for autologous treatment of premature ovarian failure and also for autologous stem cell therapy of neurodegenerative diseases without use of allogeneic embryonic stem cells or somatic cell nuclear transfer. The in vivo application of sex steroid combinations may augment the proliferation of existing neural stem cells and their differentiation into mature neuronal cells (systemic regenerative therapy). Such treatment may also stimulate the transdifferentiation of autologous neural stem cell precursors into neural stem cells useful for topical or systemic regenerative treatment.

  18. Engineering Replacement Tissues with Amniotic Stem Cells

    DTIC Science & Technology

    2012-10-01

    stromal cells. Stem Cells, 2007. 25(3): p. 655-63. 12. Ivan, M., et al., HIFalpha targeted for VHL -mediated destruction by proline hydroxylation...11. Ivan, M., et al., HIFalpha targeted for VHL -mediated destruction by proline hydroxylation: implications for O2 sensing. Science, 2001. 292(5516

  19. Altered Metabolic and Stemness Capacity of Adipose Tissue-Derived Stem Cells from Obese Mouse and Human

    PubMed Central

    Pérez, Laura M.; Bernal, Aurora; de Lucas, Beatriz; San Martin, Nuria; Mastrangelo, Annalaura; García, Antonia; Barbas, Coral; Gálvez, Beatriz G.

    2015-01-01

    Adipose stem cells (ASCs) are an appealing source of cells for therapeutic intervention; however, the environment from which ASCs are isolated may impact their usefulness. Using a range of functional assays, we have evaluated whether ASCs isolated from an obese environment are comparable to cells from non-obese adipose tissue. Results showed that ASCs isolated from obese tissue have a reduced proliferative ability and a loss of viability together with changes in telomerase activity and DNA telomere length, suggesting a decreased self-renewal capacity. Metabolic analysis demonstrated that mitochondrial content and function was impaired in obese-derived ASCs resulting in changes in favored oxidative substrates. These findings highlight the impact of obesity on adult stem properties. Hence, caution should be exercised when considering the source of ASCs for cellular therapies since their therapeutic potential may be impaired. PMID:25875023

  20. Altered metabolic and stemness capacity of adipose tissue-derived stem cells from obese mouse and human.

    PubMed

    Pérez, Laura M; Bernal, Aurora; de Lucas, Beatriz; San Martin, Nuria; Mastrangelo, Annalaura; García, Antonia; Barbas, Coral; Gálvez, Beatriz G

    2015-01-01

    Adipose stem cells (ASCs) are an appealing source of cells for therapeutic intervention; however, the environment from which ASCs are isolated may impact their usefulness. Using a range of functional assays, we have evaluated whether ASCs isolated from an obese environment are comparable to cells from non-obese adipose tissue. Results showed that ASCs isolated from obese tissue have a reduced proliferative ability and a loss of viability together with changes in telomerase activity and DNA telomere length, suggesting a decreased self-renewal capacity. Metabolic analysis demonstrated that mitochondrial content and function was impaired in obese-derived ASCs resulting in changes in favored oxidative substrates. These findings highlight the impact of obesity on adult stem properties. Hence, caution should be exercised when considering the source of ASCs for cellular therapies since their therapeutic potential may be impaired.

  1. Multiscale patterned transplantable stem cell patches for bone tissue regeneration.

    PubMed

    Kim, Jangho; Bae, Won-Gyu; Choung, Han-Wool; Lim, Ki Taek; Seonwoo, Hoon; Jeong, Hoon Eui; Suh, Khap-Yang; Jeon, Noo Li; Choung, Pill-Hoon; Chung, Jong Hoon

    2014-11-01

    Stem cell-based therapy has been proposed as an enabling alternative not only for the treatment of diseases but also for the regeneration of tissues beyond complex surgical treatments or tissue transplantation. In this study, we approached a conceptual platform that can integrate stem cells into a multiscale patterned substrate for bone regeneration. Inspired by human bone tissue, we developed hierarchically micro- and nanopatterned transplantable patches as synthetic extracellular matrices by employing capillary force lithography in combination with a surface micro-wrinkling method using a poly(lactic-co-glycolic acid) (PLGA) polymer. The multiscale patterned PLGA patches were highly flexible and showed higher tissue adhesion to the underlying tissue than did the single nanopatterned patches. In response to the anisotropically multiscale patterned topography, the adhesion and differentiation of human mesenchymal stem cells (hMSCs) were sensitively controlled. Furthermore, the stem cell patch composed of hMSCs and transplantable PLGA substrate promoted bone regeneration in vivo when both the micro- and nanotopography of the substrate surfaces were synergistically combined. Thus, our study concludes that multiscale patterned transplantable stem cell patches may have a great potential for bone regeneration as well as for various regenerative medicine approaches.

  2. Wildtype adult stem cells, unlike tumor cells, are resistant to cellular damages in Drosophila.

    PubMed

    Ma, Meifang; Zhao, Hang; Zhao, Hanfei; Binari, Richard; Perrimon, Norbert; Li, Zhouhua

    2016-03-15

    Adult stem cells or residential progenitor cells are critical to maintain the structure and function of adult tissues (homeostasis) throughout the lifetime of an individual. Mis-regulation of stem cell proliferation and differentiation often leads to diseases including cancer, however, how wildtype adult stem cells and cancer cells respond to cellular damages remains unclear. We find that in the adult Drosophila midgut, intestinal stem cells (ISCs), unlike tumor intestinal cells, are resistant to various cellular damages. Tumor intestinal cells, unlike wildtype ISCs, are easily eliminated by apoptosis. Further, their proliferation is inhibited upon autophagy induction, and autophagy-mediated tumor inhibition is independent of caspase-dependent apoptosis. Interestingly, inhibition of tumorigenesis by autophagy is likely through the sequestration and degradation of mitochondria, as compromising mitochondria activity in these tumor models mimics the induction of autophagy and increasing the production of mitochondria alleviates the tumor-suppression capacity of autophagy. Together, these data demonstrate that wildtype adult stem cells and tumor cells show dramatic differences in sensitivity to cellular damages, thus providing potential therapeutic implications targeting tumorigenesis.

  3. REST regulation of gene networks in adult neural stem cells

    PubMed Central

    Mukherjee, Shradha; Brulet, Rebecca; Zhang, Ling; Hsieh, Jenny

    2016-01-01

    Adult hippocampal neural stem cells generate newborn neurons throughout life due to their ability to self-renew and exist as quiescent neural progenitors (QNPs) before differentiating into transit-amplifying progenitors (TAPs) and newborn neurons. The mechanisms that control adult neural stem cell self-renewal are still largely unknown. Conditional knockout of REST (repressor element 1-silencing transcription factor) results in precocious activation of QNPs and reduced neurogenesis over time. To gain insight into the molecular mechanisms by which REST regulates adult neural stem cells, we perform chromatin immunoprecipitation sequencing and RNA-sequencing to identify direct REST target genes. We find REST regulates both QNPs and TAPs, and importantly, ribosome biogenesis, cell cycle and neuronal genes in the process. Furthermore, overexpression of individual REST target ribosome biogenesis or cell cycle genes is sufficient to induce activation of QNPs. Our data define novel REST targets to maintain the quiescent neural stem cell state. PMID:27819263

  4. REST regulation of gene networks in adult neural stem cells.

    PubMed

    Mukherjee, Shradha; Brulet, Rebecca; Zhang, Ling; Hsieh, Jenny

    2016-11-07

    Adult hippocampal neural stem cells generate newborn neurons throughout life due to their ability to self-renew and exist as quiescent neural progenitors (QNPs) before differentiating into transit-amplifying progenitors (TAPs) and newborn neurons. The mechanisms that control adult neural stem cell self-renewal are still largely unknown. Conditional knockout of REST (repressor element 1-silencing transcription factor) results in precocious activation of QNPs and reduced neurogenesis over time. To gain insight into the molecular mechanisms by which REST regulates adult neural stem cells, we perform chromatin immunoprecipitation sequencing and RNA-sequencing to identify direct REST target genes. We find REST regulates both QNPs and TAPs, and importantly, ribosome biogenesis, cell cycle and neuronal genes in the process. Furthermore, overexpression of individual REST target ribosome biogenesis or cell cycle genes is sufficient to induce activation of QNPs. Our data define novel REST targets to maintain the quiescent neural stem cell state.

  5. Somatic stem cells express Piwi and Vasa genes in an adult ctenophore: ancient association of "germline genes" with stemness.

    PubMed

    Alié, Alexandre; Leclère, Lucas; Jager, Muriel; Dayraud, Cyrielle; Chang, Patrick; Le Guyader, Hervé; Quéinnec, Eric; Manuel, Michaël

    2011-02-01

    Stem cells are essential for animal development and adult tissue homeostasis, and the quest for an ancestral gene fingerprint of stemness is a major challenge for evolutionary developmental biology. Recent studies have indicated that a series of genes, including the transposon silencer Piwi and the translational activator Vasa, specifically involved in germline determination and maintenance in classical bilaterian models (e.g., vertebrates, fly, nematode), are more generally expressed in adult multipotent stem cells in other animals like flatworms and hydras. Since the progeny of these multipotent stem cells includes both somatic and germinal derivatives, it remains unclear whether Vasa, Piwi, and associated genes like Bruno and PL10 were ancestrally linked to stemness, or to germinal potential. We have investigated the expression of Vasa, two Piwi paralogues, Bruno and PL10 in Pleurobrachia pileus, a member of the early-diverging phylum Ctenophora, the probable sister group of cnidarians. These genes were all expressed in the male and female germlines, and with the exception of one of the Piwi paralogues, they showed similar expression patterns within somatic territories (tentacle root, comb rows, aboral sensory complex). Cytological observations and EdU DNA-labelling and long-term retention experiments revealed concentrations of stem cells closely matching these gene expression areas. These stem cell pools are spatially restricted, and each specialised in the production of particular types of somatic cells. These data unveil important aspects of cell renewal within the ctenophore body and suggest that Piwi, Vasa, Bruno, and PL10 belong to a gene network ancestrally acting in two distinct contexts: (i) the germline and (ii) stem cells, whatever the nature of their progeny.

  6. Brain stem auditory evoked responses in human infants and adults

    NASA Technical Reports Server (NTRS)

    Hecox, K.; Galambos, R.

    1974-01-01

    Brain stem evoked potentials were recorded by conventional scalp electrodes in infants (3 weeks to 3 years of age) and adults. The latency of one of the major response components (wave V) is shown to be a function both of click intensity and the age of the subject; this latency at a given signal strength shortens postnatally to reach the adult value (about 6 msec) by 12 to 18 months of age. The demonstrated reliability and limited variability of these brain stem electrophysiological responses provide the basis for an optimistic estimate of their usefulness as an objective method for assessing hearing in infants and adults.

  7. Ethylene effects in pea stem tissue

    SciTech Connect

    Steen, D.A.; Chadwick, A.V.

    1981-01-01

    The marked effects of ethylene on pea stem growth have been investigated. Low temperatures and colchicine, both known microtubule depolymerization agents, reverse the effects of ethylene in straight growth tests. Low temperature (6 C) also profoundly reduces the effects of gas in terms of swelling, hook curvature, and horizontal mutation. Deuterium oxide, an agent capable of rigidifying microtubular structure, mimics the effects of ethylene. Electron microscopy shows that microtubule orientation is strikingly altered by ethylene. These findings indicate that some of the ethylene responses may be due to a stabilizing effect on microtubules in plant cells.

  8. 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

  9. Niche-Independent Symmetrical Self-Renewal of a Mammalian Tissue Stem Cell

    PubMed Central

    Gorba, Thorsten; Reitano, Erika; Toselli, Mauro; Biella, Gerardo; Sun, Yirui; Sanzone, Sveva; Ying, Qi-Long; Cattaneo, Elena

    2005-01-01

    Pluripotent mouse embryonic stem (ES) cells multiply in simple monoculture by symmetrical divisions. In vivo, however, stem cells are generally thought to depend on specialised cellular microenvironments and to undergo predominantly asymmetric divisions. Ex vivo expansion of pure populations of tissue stem cells has proven elusive. Neural progenitor cells are propagated in combination with differentiating progeny in floating clusters called neurospheres. The proportion of stem cells in neurospheres is low, however, and they cannot be directly observed or interrogated. Here we demonstrate that the complex neurosphere environment is dispensable for stem cell maintenance, and that the combination of fibroblast growth factor 2 (FGF-2) and epidermal growth factor (EGF) is sufficient for derivation and continuous expansion by symmetrical division of pure cultures of neural stem (NS) cells. NS cells were derived first from mouse ES cells. Neural lineage induction was followed by growth factor addition in basal culture media. In the presence of only EGF and FGF-2, resulting NS cells proliferate continuously, are diploid, and clonogenic. After prolonged expansion, they remain able to differentiate efficiently into neurons and astrocytes in vitro and upon transplantation into the adult brain. Colonies generated from single NS cells all produce neurons upon growth factor withdrawal. NS cells uniformly express morphological, cell biological, and molecular features of radial glia, developmental precursors of neurons and glia. Consistent with this profile, adherent NS cell lines can readily be established from foetal mouse brain. Similar NS cells can be generated from human ES cells and human foetal brain. The extrinsic factors EGF plus FGF-2 are sufficient to sustain pure symmetrical self-renewing divisions of NS cells. The resultant cultures constitute the first known example of tissue-specific stem cells that can be propagated without accompanying differentiation. These

  10. Isolating intestinal stem cells from adult Drosophila midguts by FACS to study stem cell behavior during aging.

    PubMed

    Tauc, Helen M; Tasdogan, Alpaslan; Pandur, Petra

    2014-12-16

    Aging tissue is characterized by a continuous decline in functional ability. Adult stem cells are crucial in maintaining tissue homeostasis particularly in tissues that have a high turnover rate such as the intestinal epithelium. However, adult stem cells are also subject to aging processes and the concomitant decline in function. The Drosophila midgut has emerged as an ideal model system to study molecular mechanisms that interfere with the intestinal stem cells' (ISCs) ability to function in tissue homeostasis. Although adult ISCs can be easily identified and isolated from midguts of young flies, it has been a major challenge to study endogenous molecular changes of ISCs during aging. This is due to the lack of a combination of molecular markers suitable to isolate ISCs from aged intestines. Here we propose a method that allows for successful dissociation of midgut tissue into living cells that can subsequently be separated into distinct populations by FACS. By using dissociated cells from the esg-Gal4, UAS-GFP fly line, in which both ISCs and the enteroblast (EB) progenitor cells express GFP, two populations of cells are distinguished based on different GFP intensities. These differences in GFP expression correlate with differences in cell size and granularity and represent enriched populations of ISCs and EBs. Intriguingly, the two GFP-positive cell populations remain distinctly separated during aging, presenting a novel technique for identifying and isolating cell populations enriched for either ISCs or EBs at any time point during aging. The further analysis, for example transcriptome analysis, of these particular cell populations at various time points during aging is now possible and this will facilitate the examination of endogenous molecular changes that occur in these cells during aging.

  11. Chemokine-mobilized adult stem cells; defining a better hematopoietic graft.

    PubMed

    Pelus, L M; Fukuda, S

    2008-03-01

    Stem cell research is currently focused on totipotent stem cells and their therapeutic potential, however adult stem cells, while restricted to differentiation within their tissue or origin, also have therapeutic utility. Transplantation with bone marrow hematopoietic stem cells (HSC) has been used for curative therapy for decades. More recently, alternative sources of HSC, particularly those induced to exit marrow or mobilize to peripheral blood by G-CSF, have become the most widely used hematopoietic graft and show significant superiority to marrow HSC. The chemokine/chemokine receptor axis also mobilizes HSC that occurs more rapidly than with G-CSF. In mice, the HSC and progenitor cells (HPC) mobilized by the CXCR2 receptor agonist GRObeta can be harvested within minutes of administration and show significantly lower levels of apoptosis, enhanced homing to marrow, expression of more activated integrin receptors and superior repopulation kinetics and more competitive engraftment than the equivalent cells mobilized by G-CSF. These characteristics suggest that chemokine axis-mobilized HSC represent a population of adult stem cells distinct from those mobilized by G-CSF, with superior therapeutic potential. It remains to be determined if the chemokine mobilization axis can be harnessed to mobilize other populations of unique adult stem cells with clinical utility.

  12. Advances in Adipose-Derived Stem Cells Isolation, Characterization, and Application in Regenerative Tissue Engineering

    PubMed Central

    Wankhade, Umesh D.; Shen, Michael; Kolhe, Ravindra; Fulzele, Sadanand

    2016-01-01

    Obesity is a complex, multifactorial disease that has been extensively researched in recent times. Obesity is characterized by excess deposition of adipose tissue in response to surplus energy. Despite the negative connotations of adipose tissue (AT), it serves as a critical endocrine organ. Adipose tissue is a source of several adipokines and cytokines which have been deemed important for both normal metabolic function and disease formation. The discoveries of metabolically active brown AT in adult humans and adipose tissue derived stem cells (ADSC) have been key findings in the past decade with potential therapeutic implications. ADSCs represent an enticing pool of multipotent adult stem cells because of their noncontroversial nature, relative abundance, ease of isolation, and expandability. A decade and a half since the discovery of ADSCs, the scientific community is still working to uncover their therapeutic potential in a wide range of diseases. In this review, we provide an overview of the recent developments in the field of ADSCs and examine their potential use in transplantation and cell-based therapies for the regeneration of diseased organs and systems. We also hope to provide perspective on how to best utilize this readily available, powerful pool of stem cells in the future. PMID:26981130

  13. Plastic adult stem cells: will they graduate from the school of hard knocks?

    PubMed

    Alison, Malcolm R; Poulsom, Richard; Otto, William R; Vig, Pamela; Brittan, Mairi; Direkze, Natalie C; Preston, Sean L; Wright, Nicholas A

    2003-02-15

    Notwithstanding the fact that adult bone marrow cell engraftment to epithelial organs seems a somewhat uncommon event, there is no doubt it does occur, and under appropriate conditions of a strong and positive selection pressure these cells will expand clonally and make a significant contribution to tissue replacement. Likewise, bone-marrow-derived cells can be amplified in vitro and differentiated into a multitude of tissues. These in essence are the goals of regenerative medicine using any source of stem cells, be it embryonic or adult. Despite such irrefutable evidence of what is possible, a veritable chorus of detractors of adult stem cell plasticity has emerged, some doubting its very existence, motivated perhaps by more than a little self-interest. The issues that have led to this state of affairs have included the inability to reproduce certain widely quoted data, one case where the apparent transdifferentiation was due to contamination of the donor tissue with haematopoietic cells and, most notoriously, extrapolating from the behaviour of embryonic stem cells to suggest that adult bone marrow cells simply fuse with other cells and adopt their phenotype. While these issues need resolving, slamming this whole new field because not everything is crystal clear is not good science. The fact that a phenomenon is quite rare in no way mitigates against its very existence: asteroid collisions with the Earth are rare, but try telling the dinosaurs they do not occur! When such events do occur (transdifferentiation or collision), they certainly can make an impact.

  14. Adipose Tissue-Derived Stem Cells for Myocardial Regeneration

    PubMed Central

    Joo, Hyung Joon; Kim, Jong-Ho

    2017-01-01

    Over the past decade, stem cell therapy has been extensively studied for clinical application for heart diseases. Among various stem cells, adipose tissue-derived stem cell (ADSC) is still an attractive stem cell resource due to its abundance and easy accessibility. In vitro studies showed the multipotent differentiation potentials of ADSC, even differentiation into cardiomyocytes. Many pre-clinical animal studies have also demonstrated promising therapeutic results of ADSC. Furthermore, there were several clinical trials showing the positive results in acute myocardial infarction using ADSC. The present article covers the brief introduction, the suggested therapeutic mechanisms, application methods including cell dose and delivery, and human clinical trials of ADSC for myocardial regeneration. PMID:28382066

  15. How electromagnetic fields can influence adult stem cells: positive and negative impacts.

    PubMed

    Maziarz, Aleksandra; Kocan, Beata; Bester, Mariusz; Budzik, Sylwia; Cholewa, Marian; Ochiya, Takahiro; Banas, Agnieszka

    2016-04-18

    The electromagnetic field (EMF) has a great impact on our body. It has been successfully used in physiotherapy for the treatment of bone disorders and osteoarthritis, as well as for cartilage regeneration or pain reduction. Recently, EMFs have also been applied in in vitro experiments on cell/stem cell cultures. Stem cells reside in almost all tissues within the human body, where they exhibit various potential. These cells are of great importance because they control homeostasis, regeneration, and healing. Nevertheless, stem cells when become cancer stem cells, may influence the pathological condition. In this article we review the current knowledge on the effects of EMFs on human adult stem cell biology, such as proliferation, the cell cycle, or differentiation. We present the characteristics of the EMFs used in miscellaneous assays. Most research has so far been performed during osteogenic and chondrogenic differentiation of mesenchymal stem cells. It has been demonstrated that the effects of EMF stimulation depend on the intensity and frequency of the EMF and the time of exposure to it. However, other factors may affect these processes, such as growth factors, reactive oxygen species, and so forth. Exploration of this research area may enhance the development of EMF-based technologies used in medical applications and thereby improve stem cell-based therapy and tissue engineering.

  16. A novel view of the adult bone marrow stem cell hierarchy and stem cell trafficking

    PubMed Central

    Ratajczak, M Z

    2015-01-01

    This review presents a novel view and working hypothesis about the hierarchy within the adult bone marrow stem cell compartment and the still-intriguing question of whether adult bone marrow contains primitive stem cells from early embryonic development, such as cells derived from the epiblast, migrating primordial germ cells or yolk sac-derived hemangioblasts. It also presents a novel view of the mechanisms that govern stem cell mobilization and homing, with special emphasis on the role of the complement cascade as a trigger for egress of hematopoietic stem cells from bone marrow into blood as well as the emerging role of novel homing factors and priming mechanisms that support stromal-derived factor 1-mediated homing of hematopoietic stem/progenitor cells after transplantation. PMID:25486871

  17. Pluripotency of adult stem cells derived from human and rat pancreas

    NASA Astrophysics Data System (ADS)

    Kruse, C.; Birth, M.; Rohwedel, J.; Assmuth, K.; Goepel, A.; Wedel, T.

    Adult stem cells are undifferentiated cells found within fully developed tissues or organs of an adult individuum. Until recently, these cells have been considered to bear less self-renewal ability and differentiation potency compared to embryonic stem cells. In recent studies an undifferentiated cell type was found in primary cultures of isolated acini from exocrine pancreas termed pancreatic stellate cells. Here we show that pancreatic stellate-like cells have the capacity of extended self-renewal and are able to differentiate spontaneously into cell types of all three germ layers expressing markers for smooth muscle cells, neurons, glial cells, epithelial cells, chondrocytes and secretory cells (insulin, amylase). Differentiation and subsequent formation of three-dimensional cellular aggregates (organoid bodies) were induced by merely culturing pancreatic stellate-like cells in hanging drops. These cells were developed into stable, long-term, in vitro cultures of both primary undifferentiated cell lines as well as organoid cultures. Thus, evidence is given that cell lineages of endodermal, mesodermal, and ectodermal origin arise spontaneously from a single adult undifferentiated cell type. Based on the present findings it is assumed that pancreatic stellate-like cells are a new class of lineage uncommitted pluripotent adult stem cells with a remarkable self-renewal ability and differentiation potency. The data emphasize the versatility of adult stem cells and may lead to a reappraisal of their use for the treatment of inherited disorders or acquired degenerative diseases.

  18. Differentiation and characteristics of undifferentiated mesenchymal stem cells originating from adult premolar periodontal ligaments

    PubMed Central

    Kwon, Dae-Woo; Im, Insook; Kim, Yong-Deok; Hwang, Dae-Seok; Holliday, L Shannon; Donatelli, Richard E; Son, Woo-Sung; Jun, Eun-Sook

    2012-01-01

    Objective The purpose of this study was to investigate the isolation and characterization of multipotent human periodontal ligament (PDL) stem cells and to assess their ability to differentiate into bone, cartilage, and adipose tissue. Methods PDL stem cells were isolated from 7 extracted human premolar teeth. Human PDL cells were expanded in culture, stained using anti-CD29, -CD34, -CD44, and -STRO-1 antibodies, and sorted by fluorescent activated cell sorting (FACS). Gingival fibroblasts (GFs) served as a positive control. PDL stem cells and GFs were cultured using standard conditions conducive for osteogenic, chondrogenic, or adipogenic differentiation. Results An average of 152.8 ± 27.6 colony-forming units was present at day 7 in cultures of PDL stem cells. At day 4, PDL stem cells exhibited a significant increase in proliferation (p < 0.05), reaching nearly double the proliferation rate of GFs. About 5.6 ± 4.5% of cells in human PDL tissues were strongly STRO-1-positive. In osteogenic cultures, calcium nodules were observed by day 21 in PDL stem cells, which showed more intense calcium staining than GF cultures. In adipogenic cultures, both cell populations showed positive Oil Red O staining by day 21. Additionally, in chondrogenic cultures, PDL stem cells expressed collagen type II by day 21. Conclusions The PDL contains multipotent stem cells that have the potential to differentiate into osteoblasts, chondrocytes, and adipocytes. This adult PDL stem cell population can be utilized as potential sources of PDL in tissue engineering applications. PMID:23323245

  19. Endothelial juxtaposition of distinct adult stem cells activates angiogenesis signaling molecules in endothelial cells.

    PubMed

    Mohammadi, Elham; Nassiri, Seyed Mahdi; Rahbarghazi, Reza; Siavashi, Vahid; Araghi, Atefeh

    2015-12-01

    Efficacy of therapeutic angiogenesis needs a comprehensive understanding of endothelial cell (EC) function and biological factors and cells that interplay with ECs. Stem cells are considered the key components of pro- and anti-angiogenic milieu in a wide variety of physiopathological states, and interactions of EC-stem cells have been the subject of controversy in recent years. In this study, the potential effects of three tissue-specific adult stem cells, namely rat marrow-derived mesenchymal stem cells (rBMSCs), rat adipose-derived stem cells (rADSCs) and rat muscle-derived satellite cells (rSCs), on the endothelial activation of key angiogenic signaling molecules, including VEGF, Ang-2, VEGFR-2, Tie-2, and Tie2-pho, were investigated. Human umbilical vein endothelial cells (HUVECs) and rat lung microvascular endothelial cells (RLMECs) were cocultured with the stem cells or incubated with the stem cell-derived conditioned media on Matrigel. Following HUVEC-stem cell coculture, CD31-positive ECs were flow sorted and subjected to western blotting to analyze potential changes in the expression of the pro-angiogenic signaling molecules. Elongation and co-alignment of the stem cells were seen along the EC tubes in the EC-stem cell cocultures on Matrigel, with cell-to-cell dye communication in the EC-rBMSC cocultures. Moreover, rBMSCs and rADSCs significantly improved endothelial tubulogenesis in both juxtacrine and paracrine manners. These two latter stem cells dynamically up-regulated VEGF, Ang-2, VREGR-2, and Tie-2 but down-regulated Tie2-pho and the Tie2-pho/Tie-2 ratio in HUVECs. Induction of pro-angiogenic signaling in ECs by marrow- and adipose-derived MSCs further indicates the significance of stem cell milieu in angiogenesis dynamics.

  20. Why Adult Stem Cell Functionality Declines with Age? Studies from the Fruit Fly Drosophila Melanogaster Model Organism

    PubMed Central

    Gonen, Oren; Toledano, Hila

    2014-01-01

    Highly regenerative adult tissues are supported by rare populations of stem cells that continuously divide to self-renew and generate differentiated progeny. This process is tightly regulated by signals emanating from surrounding cells to fulfill the dynamic demands of the tissue. One of the hallmarks of aging is slow and aberrant tissue regeneration due to deteriorated function of stem and supporting cells. Several Drosophila regenerative tissues are unique in that they provide exact identification of stem and neighboring cells in whole-tissue anatomy. This allows for precise tracking of age-related changes as well as their targeted manipulation within the tissue. In this review we present the stem cell niche of Drosophila testis, ovary and intestine and describe the major changes and phenotypes that occur in the course of aging. Specifically we discuss changes in both intrinsic properties of stem cells and their microenvironment that contribute to the decline in tissue functionality. Understanding these mechanisms in adult Drosophila tissues will likely provide new paradigms in the field of aging. PMID:24955030

  1. Treatment Option Overview (Adult Soft Tissue Sarcoma)

    MedlinePlus

    ... superficial (in subcutaneous tissue with no spread into connective tissue or muscle below) or deep (in the muscle ... superficial (in subcutaneous tissue with no spread into connective tissue or muscle below) or deep (in the muscle ...

  2. Treatment Options for Adult Soft Tissue Sarcoma

    MedlinePlus

    ... superficial (in subcutaneous tissue with no spread into connective tissue or muscle below) or deep (in the muscle ... superficial (in subcutaneous tissue with no spread into connective tissue or muscle below) or deep (in the muscle ...

  3. General Information about Adult Soft Tissue Sarcoma

    MedlinePlus

    ... superficial (in subcutaneous tissue with no spread into connective tissue or muscle below) or deep (in the muscle ... superficial (in subcutaneous tissue with no spread into connective tissue or muscle below) or deep (in the muscle ...

  4. Stages of Adult Soft Tissue Sarcoma

    MedlinePlus

    ... superficial (in subcutaneous tissue with no spread into connective tissue or muscle below) or deep (in the muscle ... superficial (in subcutaneous tissue with no spread into connective tissue or muscle below) or deep (in the muscle ...

  5. Human stem cells and articular cartilage tissue engineering.

    PubMed

    Stoltz, J-F; Huselstein, C; Schiavi, J; Li, Y Y; Bensoussan, D; Decot, V; De Isla, N

    2012-12-01

    Injuries to articular cartilage are one of the most challenging issues of musculoskeletal medicine due to the poor intrinsic ability of this tissue for repair. Despite progress in orthopaedic surgery, cell-based surgical therapies such as autologous chondrocyte transplantation (ACT) have been in clinical use for cartilage repair for over a decade but this approach has shown mixed results. Moreover, the lack of efficient modalities of treatment for large chondral defects has prompted research on cartilage tissue engineering combining cells, scaffold materials and environmental factors. This paper focuses on the main parameters in tissue engineering and in particular, on the potential of mesenchymal stem cells (MSCs) as an alternative to cells derived from patient tissues in autologous transplantation and tissue engineering. We discussed the prospects of using autologous chondrocytes or MSCs in regenerative medicine and summarized the advantages and disadvantages of these cells in articular cartilage engineering.

  6. Advantages of Sheep Infrapatellar Fat Pad Adipose Tissue Derived Stem Cells in Tissue Engineering

    PubMed Central

    Vahedi, Parviz; Soleimanirad, Jafar; Roshangar, Leila; Shafaei, Hajar; Jarolmasjed, Seyedhosein; Nozad Charoudeh, Hojjatollah

    2016-01-01

    Purpose: The goal of this study has been to evaluate adipose tissue derived stem cells (ADSCs) from infrapatellar fat pad and characterize their cell surface markers using anti-human antibodies, as adipose tissue derived stem cells (ADSCs) have great potential for cellular therapies to restore injured tissues. Methods: Adipose tissue was obtained from infrapatellar fat pad of sheep. Surface markers evaluated by flow cytometry. In order to evaluate cell adhesion, the Polycaprolactone (PCL) was sterilized under Ultraviolet (UV) light and about 1×105 cells were seeded on PCL. Then, ASCs- PCL construct were evaluated by Scanning Electron Microscopy (Mira3 Te Scan, Czech Republic). Results: We showed that adipose tissue derived stem cells (ADSCs) maintain their fibroblastic-like morphology during different subcultures and cell adhesion. They were positive for CD44 and CD90 markers and negative for CD31 and Cd45 markers by human antibodies. Conclusion: Our results suggest that ASCs surface markers can be characterized by anti-human antibodies in sheep. As stem cells, they can be used in tissue engineering. PMID:27123425

  7. Stem Cells and Tissue Niche: Two Faces of the Same Coin of Muscle Regeneration

    PubMed Central

    Scicchitano, Bianca Maria; Sica, Gigliola; Musarò, Antonio

    2016-01-01

    Capacity of adult muscle to regenerate in response to injury stimuli represents an important homeostatic process. Regeneration is a highly coordinated program that partially recapitulates the embryonic developmental program. However, muscle regeneration is severely compromised in several pathological conditions. It is likely that the restricted tissue repair program under pathological conditions is due to either progressive loss of stem cell populations or to missing signals that limit the damaged tissues to efficiently activate a regenerative program. It is therefore plausible that loss of control over these cell fates might lead to a pathological cell transdifferentiation, limiting the ability of a pathological muscle to sustain an efficient regenerative process. The critical role of microenvironment on stem cells activity and muscle regeneration is discussed. PMID:28078070

  8. Comparative aspects of adult neural stem cell activity in vertebrates.

    PubMed

    Grandel, Heiner; Brand, Michael

    2013-03-01

    At birth or after hatching from the egg, vertebrate brains still contain neural stem cells which reside in specialized niches. In some cases, these stem cells are deployed for further postnatal development of parts of the brain until the final structure is reached. In other cases, postnatal neurogenesis continues as constitutive neurogenesis into adulthood leading to a net increase of the number of neurons with age. Yet, in other cases, stem cells fuel neuronal turnover. An example is protracted development of the cerebellar granular layer in mammals and birds, where neurogenesis continues for a few weeks postnatally until the granular layer has reached its definitive size and stem cells are used up. Cerebellar growth also provides an example of continued neurogenesis during adulthood in teleosts. Again, it is the granular layer that grows as neurogenesis continues and no definite adult cerebellar size is reached. Neuronal turnover is most clearly seen in the telencephalon of male canaries, where projection neurons are replaced in nucleus high vocal centre each year before the start of a new mating season--circuitry reconstruction to achieve changes of the song repertoire in these birds? In this review, we describe these and other examples of adult neurogenesis in different vertebrate taxa. We also compare the structure of the stem cell niches to find common themes in their organization despite different functions adult neurogenesis serves in different species. Finally, we report on regeneration of the zebrafish telencephalon after injury to highlight similarities and differences of constitutive neurogenesis and neuronal regeneration.

  9. Apple ethanol extract promotes proliferation of human adult stem cells, which involves the regenerative potential of stem cells.

    PubMed

    Lee, Jienny; Shin, Moon Sam; Kim, Mi Ok; Jang, Sunghee; Oh, Sae Woong; Kang, Mingyeong; Jung, Kwangseon; Park, Yong Seek; Lee, Jongsung

    2016-09-01

    Tissue regeneration using adult stem cells (ASCs) has significant potential as a novel treatment for many degenerative diseases. Previous studies have established that age negatively affects the proliferation status and differentiation potential of ASCs, suggesting a possible limitation in their potential therapeutic use. Therefore, we hypothesized that apple extract might exert beneficial effects on ASCs. The specific objectives were to investigate the proliferative effect of apple ethanol extract on human adipose tissue-derived mesenchymal stem cells (ADSCs) and human cord blood-derived mesenchymal stem cells (CB-MSCs), and identify the possible molecular mechanisms. Apple extract promoted proliferation of ADSCs and CB-MSCs as determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Click-iT 5-ethynyl-2'-deoxyuridine flow cytometry assays. In addition, phosphorylation of p44/42 MAPK (ERK), mammalian target of rapamycin (mTOR), p70 S6 kinase (p70S6K), S6 ribosomal protein (S6RP), eukaryotic initiation factor (eIF) 4B and eIF4E was induced stepwise in ADSCs. Furthermore, apple extract significantly induced the production of vascular endothelial growth factor and interleukin-6 in both ADSCs and CB-MSCs. Similarly, apple extract-induced phosphorylation of the mTOR/p70S6K/S6RP/eIF4B/eIF4E pathway was blocked by pretreatment with PD98059, a specific ERK inhibitor. These results indicate that apple extract-induced proliferation of ADSCs under serum-free conditions is mediated by ERK-dependent cytokine production. Moreover, the beneficial effect of apple extract on proliferation of ASCs may overcome the limitation in therapeutic use of stem cells in tissue regeneration and maintenance of stem cell homeostasis.

  10. Clinical Applications of Mesenchymal Stem Cells in Soft Tissue Augmentation

    PubMed Central

    Hanson, Summer E.; Gutowski, Karol A.; Hematti, Peiman

    2014-01-01

    Based on a variety of preclinical studies showing that mesenchymal stem cells (MSC) play a significant role in tissue repair and homeostasis, MSC have rapidly moved into a phase of clinical trials investigating their efficacy as a cell-based therapeutic modality for a diverse group of applications. An emerging body of evidence shows that in addition to being a progenitor cell population with self-renewing and multipotent differentiation capabilities, MSC have unique immunomodulatory properties, making them even more attractive for regenerative medicine. Emerging discoveries in stem cell biology have revealed a multitude of mechanisms through which MSC could potentially augment the current techniques in aesthetic surgery. In this article, the authors review the clinical advances in cell-based therapies relevant to aesthetic surgery, including tissue augmentation, rejuvenation, and regeneration. PMID:21131458

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

    PubMed Central

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

    2015-01-01

    Cell therapy is a promising approach to improve cartilage healing. Adipose tissue is an abundant and readily accessible cell source. Previous studies have demonstrated good cartilage repair results with adipose tissue mesenchymal stem cells in small animal experiments. This study aimed to examine these cells in a large animal model. Thirty knees of adult sheep were randomly allocated to three treatment groups: CELLS (scaffold seeded with human adipose tissue mesenchymal stem cells), SCAFFOLD (scaffold without cells), or EMPTY (untreated lesions). A partial thickness defect was created in the medial femoral condyle. After six months, the knees were examined according to an adaptation of the International Cartilage Repair Society (ICRS 1) score, in addition to a new Partial Thickness Model scale and the ICRS macroscopic score. All of the animals completed the follow-up period. The CELLS group presented with the highest ICRS 1 score (8.3 ± 3.1), followed by the SCAFFOLD group (5.6 ± 2.2) and the EMPTY group (5.2 ± 2.4) (p = 0.033). Other scores were not significantly different. These results suggest that human adipose tissue mesenchymal stem cells promoted satisfactory cartilage repair in the ovine model. PMID:26569221

  12. Pharmacological Regulation of In Situ Tissue Stem Cells Differentiation for Soft Tissue Calcification Treatment.

    PubMed

    Hu, Jia-Jie; Yin, Zi; Shen, Wei-Liang; Xie, Yu-Bin; Zhu, Ting; Lu, Ping; Cai, You-Zhi; Kong, Min-Jian; Heng, Boon Chin; Zhou, Yi-Ting; Chen, Wei-Shan; Chen, Xiao; Ouyang, Hong-Wei

    2016-04-01

    Calcification of soft tissues, such as heart valves and tendons, is a common clinical problem with limited therapeutics. Tissue specific stem/progenitor cells proliferate to repopulate injured tissues. But some of them become divergent to the direction of ossification in the local pathological microenvironment, thereby representing a cellular target for pharmacological approach. We observed that HIF-2alpha (encoded by EPAS1 inclined form) signaling is markedly activated within stem/progenitor cells recruited at calcified sites of diseased human tendons and heart valves. Proinflammatory microenvironment, rather than hypoxia, is correlated with HIF-2alpha activation and promoted osteochondrogenic differentiation of tendon stem/progenitor cells (TSPCs). Abnormal upregulation of HIF-2alpha served as a key switch to direct TSPCs differentiation into osteochondral-lineage rather than teno-lineage. Notably, Scleraxis (Scx), an essential tendon specific transcription factor, was suppressed on constitutive activation of HIF-2alpha and mediated the effect of HIF-2alpha on TSPCs fate decision. Moreover, pharmacological inhibition of HIF-2alpha with digoxin, which is a widely utilized drug, can efficiently inhibit calcification and enhance tenogenesis in vitro and in the Achilles's tendinopathy model. Taken together, these findings reveal the significant role of the tissue stem/progenitor cells fate decision and suggest that pharmacological regulation of HIF-2alpha function is a promising approach for soft tissue calcification treatment.

  13. Isolation and cultivation of stem cells from adult mouse testes.

    PubMed

    Guan, Kaomei; Wolf, Frieder; Becker, Alexander; Engel, Wolfgang; Nayernia, Karim; Hasenfuss, Gerd

    2009-01-01

    The successful isolation and cultivation of spermatogonial stem cells (SSCs) as well as induction of SSCs into pluripotent stem cells will allow us to study their biological characteristics and their applications in therapeutic approaches. Here we provide step-by-step procedures on the basis of previous work in our laboratory for: the isolation of testicular cells from adolescent mice by a modified enzymatic procedure; the enrichment of undifferentiated spermatogonia by laminin selection or genetic selection using Stra8-EGFP (enhanced green fluorescent protein) transgenic mice; the cultivation and conversion of undifferentiated spermatogonia into embryonic stem-like cells, so-called multipotent adult germline stem cells (maGSCs); and characterization of these cells. Normally, it will take about 16 weeks to obtain stable maGSC lines starting from the isolation of testicular cells.

  14. Small molecule-based approaches to adult stem cell therapies.

    PubMed

    Lairson, Luke L; Lyssiotis, Costas A; Zhu, Shoutian; Schultz, Peter G

    2013-01-01

    There is considerable interest in the development of stem cell-based strategies for the treatment of a broad range of human diseases, including neurodegenerative, autoimmune, cardiovascular, and musculoskeletal diseases. To date, such regenerative approaches have focused largely on the development of cell transplantation therapies using cells derived from pluripotent embryonic stem cells (ESCs). Although there have been exciting preliminary reports describing the efficacy of ESC-derived replacement therapies, approaches involving ex vivo manipulated ESCs are hindered by issues of mutation, immune rejection, and ethical controversy. An alternative approach involves direct in vivo modulation or ex vivo expansion of endogenous adult stem cell populations using drug-like small molecules. Here we describe chemical approaches to the regulation of somatic stem cell biology that are yielding new biological insights and that may ultimately lead to innovative new medicines.

  15. Adult tissue sources for new β cells.

    PubMed

    Nichols, Robert J; New, Connie; Annes, Justin P

    2014-04-01

    The diabetes pandemic incurs extraordinary public health and financial costs that are projected to expand for the foreseeable future. Consequently, the development of definitive therapies for diabetes is a priority. Currently, a wide spectrum of therapeutic strategies-from implantable insulin delivery devices to transplantation-based cell replacement therapy, to β-cell regeneration-focus on replacing the lost insulin-producing capacity of individuals with diabetes. Among these, β-cell regeneration remains promising but heretofore unproved. Indeed, recent experimental work has uncovered surprising biology that underscores the potential therapeutic benefit of β-cell regeneration. These studies have elucidated a variety of sources for the endogenous production of new β cells from existing cells. First, β cells, long thought to be postmitotic, have demonstrated the potential for regenerative capacity. Second, the presence of pancreatic facultative endocrine progenitor cells has been established. Third, the malleability of cellular identity has availed the possibility of generating β cells from other differentiated cell types. Here, we review the exciting developments surrounding endogenous sources of β-cell production and consider the potential of realizing a regenerative therapy for diabetes from adult tissues.

  16. Mesenchymal stem cells from different murine tissues have differential capacity to metabolize extracellular nucleotides.

    PubMed

    Iser, Isabele C; Bracco, Paula A; Gonçalves, Carlos E I; Zanin, Rafael F; Nardi, Nance B; Lenz, Guido; Battastini, Ana Maria O; Wink, Márcia R

    2014-10-01

    Mesenchymal stem cells (MSCs) have shown a great potential for cell-based therapy and many different therapeutic purposes. Despite the recent advances in the knowledge of MSCs biology, their biochemical and molecular properties are still poorly defined. Ecto-nucleoside triphosphate diphosphohydrolases (E-NTPDases) and ecto-5'-nucleotidase (eNT/CD73) are widely expressed enzymes that hydrolyze extracellular nucleotides, generating an important cellular signaling cascade. Currently, studies have evidenced the relationship between the purinergic system and the development, maintenance, and differentiation of stem cells. The objective of this study is to identify the NTPDases and eNT/CD73 and compare the levels of nucleotide hydrolysis on MSCs isolated from different murine tissues (bone marrow, lung, vena cava, kidney, pancreas, spleen, skin, and adipose tissue). MSCs from all tissues investigated expressed the ectoenzymes at different levels. In MSCs from pancreas and adipose tissue, the hydrolysis of triphosphonucleosides was significantly higher when compared to the other cells. The diphosphonucleosides were hydrolyzed at a higher rate by MSC from pancreas when compared to MSC from other tissues. The differential nucleotide hydrolysis activity and enzyme expression in these cells suggests that MSCs play different roles in regulating the purinergic system in these tissues. Overall MSCs are an attractive adult-derived cell population for therapies, however, the fact that ecto-nucleotide metabolism can affect the microenvironment, modulating important events, such as immune response, makes the assessment of this metabolism an important part of the characterization of MSCs to be applied therapeutically.

  17. DIRECTED DIFFERENTIATION OF EMBRYONIC STEM CELLS INTO BLADDER TISSUE

    PubMed Central

    Oottamasathien, Siam; Wang, YongQing; Williams, Karin; Franco, Omar E.; Wills, Marcia L.; Thomas, John C.; Saba, Katrina; Sharif-Afshar, Ali-Reza; Makari, John H.; Bhowmick, Neil A; DeMarco, Romano T.; Hipkens, Susan; Magnuson, Mark; Brock, John W.; Hayward, Simon W.; Pope, John C.; Matusik, Robert J.

    2007-01-01

    Manipulatable models of bladder development which interrogate specific pathways are badly needed. Such models will allow a systematic investigation of the multitude of pathologies which result from developmental defects of the urinary bladder. In the present communication, we describe a model in which mouse embryonic stem (ES) cells are directed to differentiate to form bladder tissue by specific interactions with fetal bladder mesenchyme. This model allows us to visualize the various stages in the differentiation of urothelium from ES cells, including the commitment to an endodermal cell lineage, with the temporal profile characterized by examining the induction of specific endodermal transcription factors (Foxa1 and Foxa2). In addition, final functional urothelial differentiation was characterized by examining uroplakin expression. It is well established that ES cells will spontaneously develop teratomas when grown within immunocompromised mouse hosts. We determined the specific mesenchymal to ES cell ratios necessary to dictate organ-specific differentiation while completely suppressing teratomatous growth. Embryonic mesenchyme is well established as an inductive tissue which dictates organ-specific programming of epithelial tissues. The present study demonstrates that embryonic bladder mesenchyme can also steer ES cells towards developing specific endodermal derived urothelium. These approaches allow us to capture specific stages of stem cell differentiation and to better define stem cell hierarchies. PMID:17289017

  18. Stem Cell Health and Tissue Regeneration in Microgravity

    PubMed Central

    Blaber, Elizabeth; Sato, Kevin; Almeida, Eduardo A.C.

    2014-01-01

    Abstract Exposure to microgravity causes significant mechanical unloading of mammalian tissues, resulting in rapid alterations of their physiology, which poses a significant risk for long-duration manned spaceflight. The immediate degenerative effects of spaceflight we understand best are those studied during short-term low-Earth-orbit experiments, and include rapid microgravity-adaptive bone and muscle loss, loss of cardiovascular capacity, defects in wound and bone fracture healing, and impaired immune function. Over the long-term, exposure to microgravity may cause severe deficits in mammalian stem cell-based tissue regenerative health, including, osteogenesis, hematopoiesis, and lymphopoeisis, as well as cause significant stem cell-based tissue degeneration in amphibian tail and lens regeneration. To address the needs for stem cell and other cell science research on the International Space Station (ISS), NASA has developed the new Bioculture System that will allow investigators to initiate and conduct on-orbit experiments that astronauts will be able to monitor and interact with during the course of cell cultures. This cell culture capability combined with advanced technologies for molecular biology and on-orbit measurement of gene expression (WetLab2) and other tools that are now coming online bring the ISS National Laboratory a step closer to becoming a fully functional space laboratory for advancing space biological sciences. PMID:25457968

  19. Enhanced ex vivo expansion of adult mesenchymal stem cells by fetal mesenchymal stem cell ECM.

    PubMed

    Ng, Chee Ping; Sharif, Abdul Rahim Mohamed; Heath, Daniel E; Chow, John W; Zhang, Claire B Y; Chan-Park, Mary B; Hammond, Paula T; Chan, Jerry K Y; Griffith, Linda G

    2014-04-01

    Large-scale expansion of highly functional adult human mesenchymal stem cells (aMSCs) remains technologically challenging as aMSCs lose self renewal capacity and multipotency during traditional long-term culture and their quality/quantity declines with donor age and disease. Identification of culture conditions enabling prolonged expansion and rejuvenation would have dramatic impact in regenerative medicine. aMSC-derived decellularized extracellular matrix (ECM) has been shown to provide such microenvironment which promotes MSC self renewal and "stemness". Since previous studies have demonstrated superior proliferation and osteogenic potential of human fetal MSCs (fMSCs), we hypothesize that their ECM may promote expansion of clinically relevant aMSCs. We demonstrated that aMSCs were more proliferative (∼ 1.6 ×) on fMSC-derived ECM than aMSC-derived ECMs and traditional tissue culture wares (TCPS). These aMSCs were smaller and more uniform in size (median ± interquartile range: 15.5 ± 4.1 μm versus 17.2 ± 5.0 μm and 15.5 ± 4.1 μm for aMSC ECM and TCPS respectively), exhibited the necessary biomarker signatures, and stained positive for osteogenic, adipogenic and chondrogenic expressions; indications that they maintained multipotency during culture. Furthermore, fMSC ECM improved the proliferation (∼ 2.2 ×), size (19.6 ± 11.9 μm vs 30.2 ± 14.5 μm) and differentiation potential in late-passaged aMSCs compared to TCPS. In conclusion, we have established fMSC ECM as a promising cell culture platform for ex vivo expansion of aMSCs.

  20. Stem cell signaling. An integral program for tissue renewal and regeneration: Wnt signaling and stem cell control.

    PubMed

    Clevers, Hans; Loh, Kyle M; Nusse, Roel

    2014-10-03

    Stem cells fuel tissue development, renewal, and regeneration, and these activities are controlled by the local stem cell microenvironment, the "niche." Wnt signals emanating from the niche can act as self-renewal factors for stem cells in multiple mammalian tissues. Wnt proteins are lipid-modified, which constrains them to act as short-range cellular signals. The locality of Wnt signaling dictates that stem cells exiting the Wnt signaling domain differentiate, spatially delimiting the niche in certain tissues. In some instances, stem cells may act as or generate their own niche, enabling the self-organization of patterned tissues. In this Review, we discuss the various ways by which Wnt operates in stem cell control and, in doing so, identify an integral program for tissue renewal and regeneration.

  1. Perspectives of gene therapy in stem cell tissue engineering.

    PubMed

    Goessler, Ulrich Reinhart; Riedel, Katrin; Hormann, Karl; Riedel, Frank

    2006-01-01

    Tissue engineering is an interdisciplinary field that applies the principles of engineering and life sciences toward the development of biological substitutes that restore, maintain or improve tissue function. It is hoped that forming tissue de novo will overcome many problems in plastic surgery associated with such areas as wound healing and the immunogenicity of transplanted tissue that lead to dysfunctional repair. Gene therapy is the science of the transfer of genetic material into individuals for therapeutic purposes by altering cellular function or structure at the molecular level. Recently, tissue engineering has been used in conjunction with gene therapy as a hybrid approach. This combination of stem-cell-based tissue engineering with gene therapy has the potential to provide regenerative tissue cells within an environment of optimal regulatory protein expression and would have many benefits in various areas such as the transplantation of skin, cartilage or bone. The aim of this review is to outline tissue engineering and possible applications of gene therapy in the field of biomedical engineering as well as basic principles of gene therapy, vectors and gene delivery.

  2. Aneuploidy impairs hematopoietic stem cell fitness and is selected against in regenerating tissues in vivo

    PubMed Central

    Pfau, Sarah J.; Silberman, Rebecca E.; Knouse, Kristin A.; Amon, Angelika

    2016-01-01

    Aneuploidy, an imbalanced karyotype, is a widely observed feature of cancer cells that has long been hypothesized to promote tumorigenesis. Here we evaluate the fitness of cells with constitutional trisomy or chromosomal instability (CIN) in vivo using hematopoietic reconstitution experiments. We did not observe cancer but instead found that aneuploid hematopoietic stem cells (HSCs) exhibit decreased fitness. This reduced fitness is due at least in part to the decreased proliferative potential of aneuploid hematopoietic cells. Analyses of mice with CIN caused by a hypomorphic mutation in the gene Bub1b further support the finding that aneuploidy impairs cell proliferation in vivo. Whereas nonregenerating adult tissues are highly aneuploid in these mice, HSCs and other regenerative adult tissues are largely euploid. These findings indicate that, in vivo, mechanisms exist to select against aneuploid cells. PMID:27313317

  3. Cryopreservation of porcine spermatogonial stem cells by slow-freezing testis tissue in trehalose.

    PubMed

    Lee, Y-A; Kim, Y-H; Ha, S-J; Kim, K-J; Kim, B-J; Kim, B-G; Choi, S-H; Kim, I-C; Schmidt, J A; Ryu, B-Y

    2014-03-01

    Spermatogonial stem cells provide the foundation for continued adult spermatogenesis and their manipulation can facilitate assisted reproductive technologies or the development of transgenic animals. Because the pig is an important agricultural and biomedical research animal, the development of practical application techniques to manipulate the pig Spermatogonial stem cell is needed. The ability to preserve porcine Spermatogonial stem cell or testis tissue long term is one of these fundamental techniques. The objective of this study was to optimize methods to cryopreserve porcine Spermatogonial stem cell when freezing testis cells or testis tissue. To identify the most efficient cryopreservation technique, porcine testis cells (cell freezing) or testis tissue (tissue freezing) were frozen in medium containing dimethyl sulfoxide (DMSO) and fetal bovine serum (FBS) or DMSO, FBS, and various concentrations of trehalose (50, 100, or 200 mM). After thawing, undifferentiated germ cells were enriched and treatments were evaluated for cryopreservation efficiency. The tissue freezing method resulted in significantly greater germ cell recovery (P = 0.041) and proliferation capacity (P < 0.001) compared to the cell freezing treatment. Regardless of freezing method (cell vs. tissue), addition of 200 mM trehalose to freezing medium increased germ cell recovery and proliferation capacity compared to cells frozen using the same freezing method without trehalose. Interestingly, addition of trehalose to the tissue freezing medium significantly increased germ cell recovery (P = 0.012) and proliferation capacity (P = 0.004) compared to the cell freezing treatment supplemented with trehalose. To confirm that cryopreservation in trehalose improves the survival of Spermatogonial stem cell, testis cells enriched for undifferentiated germ cells were xenotransplanted into recipient mouse testes. Germ cells recovered from tissue frozen with 200 mM trehalose generated significantly more (P

  4. Preparation of adult muscle fiber-associated stem/precursor cells.

    PubMed

    Conboy, Michael J; Conboy, Irina M

    2010-01-01

    In our studies of muscle regeneration we have developed, modified, and optimized techniques to isolate and study the stem and precursor cells to muscle tissue. Our goals have been to obtain for study muscle fibers in bulk, or the fiber-associated cells, separately from the other cells found in muscle. Using these techniques, myofiber-associated cells may be isolated from neonatal through adult muscle, from resting or from regenerating muscle, thus allowing one to investigate the cellular populations participating during the time course of these events. The protocol is applicable to any age and condition of muscle and may be adapted for other tissues.

  5. Engineering tissue for the fetus: stem cells and matrix signalling.

    PubMed

    De Coppi, Paolo

    2014-06-01

    Congenital malformations are major causes of disease and death during the first years of life and, most of the time, functional replacement of the missing or damaged organs remains an unmet clinical need. Particularly relevant for the treatment of congenital malformation would be to collect the stem cells at diagnosis, before birth, to be able to intervene during the gestation or in the neonatal period. Human AFSCs (amniotic fluid stem cells), which have characteristics intermediate between those of embryonic and adult stem cells, have been isolated. c-Kit+Lin- cells derived from amniotic fluid display a multilineage haemopoietic potential and they can be easily reprogrammed to a pluripotent status. Although, in the future, we hope to use cells derived from the amniotic fluid, we and others have proved recently that simple organs such as the trachea can be engineered using adult progenitors utilizing decellularized cadaveric matrices. A similar approach could be used in the future for more complex organs such as the muscles, intestines or lungs.

  6. Solutes in the free space of growing stem tissues

    SciTech Connect

    Cosgrove, D.J.; Cleland, R.E.

    1983-01-01

    The concentration of osmotically active solutes in the cell wall free space of young stem tissues was studied using a variety of extraction methods. When the intercellular air spaces of etiolated pea (Pisum sativum L.) internodes were perfused with distilled H/sub 2/O, the resulting solution contained a solute concentration of about 70 milliosmoles per kilogram. A second procedure involving vacuum infiltration of segments followed by centrifugation to collect the free space solution gave similar results. Apical stem segments yielded free space extracts about twice as concentrated as those from basal portions of the stem. After correcting for dilution of the free space solution by the infiltrated water, the osmotic pressure of the undiluted free space in pea stem tissue was estimated to be 2.9 bars for apical segments, 1.8 bars for basal regions. These values may be somewhat overestimated due to solute efflux from intracellular pools during the extraction procedure. Similar results were obtained for stem regions of etiolated soybean (Glycine max (L.) Merr.) and cucumber (Cucumis sativus L.) seedlings. From measurements of the electrical conductivity and refractive index of free space extracts before and after ashing, it appears that 25% of the solutes are inorganic electrolytes and 75% are organic nonelectrolytes with an average size similar to that of glucose. A significant osmotic pressure in the wall space offers an explanation for the frequent observation that nontranspiring plants have negative water potentials. Calculations of hydraulic resistance from water potential data must take into account solutes in the free space, else apparent, but unreal, changes in resistance may be calculated. 27 references, 4 tables.

  7. Comparative analysis of mesenchymal stem cells from adult mouse adipose, muscle, and fetal muscle.

    PubMed

    Lei, Hulong; Yu, Bing; Huang, Zhiqing; Yang, Xuerong; Liu, Zehui; Mao, Xiangbing; Tian, Gang; He, Jun; Han, Guoquan; Chen, Hong; Mao, Qian; Chen, Daiwen

    2013-02-01

    Recently, increasing evidence supports that adult stem cells are the part of a natural system for tissue growth and repair. This study focused on the differences of mesenchymal stem cells from adult adipose (ADSCs), skeletal muscle (MDSCs) and fetal muscle (FMSCs) in biological characteristics, which is the key to cell therapy success. Stem cell antigen 1 (Sca-1) expression of MDSCs and FMSCs at passage 3 was two times more than that at passage 1 (P < 0.0001). After 28-day myogenic induction, higher expression levels of skeletal muscle-specific genes were observed in MDSCs than FMSCs (P < 0.01), and the lowest expression levels were demonstrated in ADSCs among three cells (P < 0.01). Besides, M-Cad and MyHC expressions in ADSCs were not detected by immunofluorescence or real-time quantitative PCR. Furthermore, after 14 days adipogenic induction, PPARγ2, LPL and aP2 mRNA expressions were higher in ADSCs vs. MDSCs (P < 0.01). Besides, MSCs from adult or fetal muscle expressed higher OCN and OPN than ADSCs after 28 days osteogenic induction (P < 0.01). Taken together, our results suggested that cell source and developmental stage had great impacts on biological properties of mesenchymal stem cells, and proper consideration of all the issues is necessary.

  8. Profiling of Sox4-dependent transcriptome in skin links tumour suppression and adult stem cell activation.

    PubMed

    Foronda, Miguel; Morgado-Palacin, Lucia; Gómez-López, Gonzalo; Domínguez, Orlando; Pisano, David G; Blasco, Maria A

    2015-12-01

    Adult stem cells (ASCs) reside in specific niches in a quiescent state in adult mammals. Upon specific cues they become activated and respond by self-renewing and differentiating into newly generated specialised cells that ensure appropriate tissue fitness. ASC quiescence also serves as a tumour suppression mechanism by hampering cellular transformation and expansion (White AC et al., 2014). Some genes restricted to early embryonic development and adult stem cell niches are often potent modulators of stem cell quiescence, and derailed expression of these is commonly associated to cancer (Vervoort SJ et al., 2013). Among them, it has been shown that recommissioned Sox4 expression facilitates proliferation, survival and migration of malignant cells. By generating a conditional Knockout mouse model in stratified epithelia (Sox4 (cKO) mice), we demonstrated a delayed plucking-induced Anagen in the absence of Sox4. Skin global transcriptome analysis revealed a prominent defect in the induction of transcriptional networks that control hair follicle stem cell (HFSC) activation such as those regulated by Wnt/Ctnnb1, Shh, Myc or Sox9, cell cycle and DNA damage response-associated pathways. Besides, Sox4 (cKO) mice are resistant to skin carcinogenesis, thus linking Sox4 to both normal and pathological HFSC activation (Foronda M et al., 2014). Here we provide additional details on the analysis of Sox4-regulated transcriptome in Telogen and Anagen skin. The raw and processed microarray data is deposited in GEO under GSE58155.

  9. Existence of reserve quiescent stem cells in adults, from amphibians to humans.

    PubMed

    Young, H E

    2004-01-01

    Several theories have been proposed to explain the phenomenon of tissue restoration in amphibians and higher order animals. These theories include dedifferentiation of damaged tissues, transdifferentiation of lineage-committed stem cells, and activation of quiescent stem cells. Young and colleagues demonstrated that connective tissues throughout the body contain multiple populations of quiescent lineage-committed progenitor stem cells and lineage-uncommitted pluripotent stem cells. Subsequent cloning and cell sorting studies identified quiescent lineage-uncommitted pluripotent mesenchymal stem cells, capable of forming any mesodermal cell type, and pluripotent epiblastic-like stem cells, capable of forming any somatic cell type. Based on their studies, they propose at least 11 categories of quiescent reserve stem cells resident within postnatal animals, including humans. These categories are pluripotent epiblastic-like stem cells, pluripotent ectodermal stem cells, pluripotent epidermal stem cells, pluripotent neuronal stem cells, pluripotent neural crest stem cells, pluripotent mesenchymal (mesodermal) stem cells, pluripotent endodermal stem cells, multipotent progenitor stem cells, tripotent progenitor stem cells, bipotent progenitor stem cells, and unipotent progenitor stem cells. Thus, activation of quiescent reserve stem cells, i.e., lineage-committed progenitor stem cells and lineage-uncommitted pluripotent stem cells, resident within the connective tissues could provide for the continual maintenance and repair of the postnatal organism after birth.

  10. A Hyaluronic Acid-Rich Node and Duct System in Which Pluripotent Adult Stem Cells Circulate.

    PubMed

    Rai, Rajani; Chandra, Vishal; Kwon, Byoung S

    2015-10-01

    Regenerative medicine is in demand of adult pluripotent stem cells (PSCs). The "Bonghan System (BHS)" was discovered and suggested to contain cells with regenerative capacity in the early 1960s. It had been ignored for a long time due to the lack of sufficient details of experiments, but about 37 years after the initial report, the BHS was rediscovered and named as the "primo vascular system." Recently, we have discovered a similar structure, which contained a high level of hyaluronic acid, and hence, named the structure as hyaluronic acid-rich node and duct system (HAR-NDS). Here we discuss the HAR-NDS concept starting from the discovery of BHS, and findings pointing to its importance in regenerative medicine. This HAR-NDS contained adult PSCs, called node and duct stem cells (NDSCs), which appeared to circulate in it. We describe the evidence that NDSCs can differentiate into hemangioblasts that further produced differentiated blood cells. The NDSCs had a potential to differentiate into neuronal cells and hepatocytes; thus, NDSCs had a capability to become cells from all three germ layers. This system appears to be a promising alternative source of adult stem cells that can be easily delivered to their target tissues and participate in tissue regeneration.

  11. Regulatory System for Stem/Progenitor Cell Niches in the Adult Rodent Pituitary

    PubMed Central

    Yoshida, Saishu; Kato, Takako; Kato, Yukio

    2016-01-01

    The anterior lobe of the pituitary gland is a master endocrine tissue composed of five types of endocrine cells. Although the turnover rate of pituitary endocrine cells is as low as about 1.6% per day, recent studies have demonstrated that Sex-determining region Y-box 2 (SOX2)+-cells exist as pituitary stem/progenitor cells in the adult anterior lobe and contribute to cell regeneration. Notably, SOX2+-pituitary stem/progenitor cells form two types of niches in this tissue: the marginal cell layer (MCL-niche) and the dense cell clusters scattering in the parenchyma (parenchymal-niche). However, little is known about the mechanisms and factors for regulating the pituitary stem/progenitor cell niches, as well as the functional differences between the two types of niches. Elucidation of the regulatory mechanisms in the niches might enable us to understand the cell regeneration system that acts in accordance with physiological demands in the adult pituitary. In this review, so as to reveal the regulatory mechanisms of the two types of niche, we summarize the regulatory factors and their roles in the adult rodent pituitary niches by focusing on three components: soluble factors, cell surface proteins and extracellular matrixes. PMID:26761002

  12. Concise review: hematopoietic stem cells and tissue stem cells: current concepts and unanswered questions.

    PubMed

    Metcalf, Donald

    2007-10-01

    The term hematopoietic stem cells has at times been used to include a miscellany of precursor cells ranging from multipotential self-generating cells to lineage-restricted progenitors with little capacity for self-generation. It is probable that the stem cells of other tissues also vary widely in their multipotentiality and proliferative capacity. This review questions several dogmas regarding the self-generative capacity of various hematopoietic cells, the single episodic origin of hematopoietic cells, and the irreversible nature of progressive mature cell formation in individual hematopoietic lineages. Disclosure of potential conflicts of interest is found at the end of this article.

  13. Brain tissue banking for stem cells for our future

    PubMed Central

    Palmero, Emily; Palmero, Sheryl; Murrell, Wayne

    2016-01-01

    In our lab we study neurogenesis and the development of brain tumors. We work towards treatment strategies for glioblastoma and towards using autologous neural stem cells for tissue regeneration strategies for brain damage and neurodegenerative disorders. It has been our policy to try to establish living cell cultures from all human biopsy material that we obtain. We hypothesized that small pieces of brain tissue could be cryopreserved and that live neural stem cells could be recovered at a later time. DMSO has been shown to possess a remarkable ability to diffuse through cell membranes and pass into cell interiors. Its chemical properties prevent the formation of damaging ice crystals thus allowing cell storage at or below −180 C. We report here a protocol for successful freezing of small pieces of tissue derived from human brain and human brain tumours. Virtually all specimens could be successfully revived. Assays of phenotype and behaviour show that the cell cultures derived were equivalent to those cultures previously derived from fresh tissue. PMID:27991551

  14. Stem Cell-Based Tissue-Engineered Laryngeal Replacement.

    PubMed

    Ansari, Tahera; Lange, Peggy; Southgate, Aaron; Greco, Karin; Carvalho, Carla; Partington, Leanne; Bullock, Anthony; MacNeil, Sheila; Lowdell, Mark W; Sibbons, Paul D; Birchall, Martin A

    2017-02-01

    Patients with laryngeal disorders may have severe morbidity relating to swallowing, vocalization, and respiratory function, for which conventional therapies are suboptimal. A tissue-engineered approach would aim to restore the vocal folds and maintain respiratory function while limiting the extent of scarring in the regenerated tissue. Under Good Laboratory Practice conditions, we decellularized porcine larynges, using detergents and enzymes under negative pressure to produce an acellular scaffold comprising cartilage, muscle, and mucosa. To assess safety and functionality before clinical trials, a decellularized hemilarynx seeded with human bone marrow-derived mesenchymal stem cells and a tissue-engineered oral mucosal sheet was implanted orthotopically into six pigs. The seeded grafts were left in situ for 6 months and assessed using computed tomography imaging, bronchoscopy, and mucosal brushings, together with vocal recording and histological analysis on explantation. The graft caused no adverse respiratory function, nor did it impact swallowing or vocalization. Rudimentary vocal folds covered by contiguous epithelium were easily identifiable. In conclusion, the proposed tissue-engineered approach represents a viable alternative treatment for laryngeal defects. Stem Cells Translational Medicine 2017;6:677-687.

  15. Dedifferentiated fat cells: an alternative source of adult multipotent cells from the adipose tissues

    PubMed Central

    Shen, Jie-fei; Sugawara, Atsunori; Yamashita, Joe; Ogura, Hideo; Sato, Soh

    2011-01-01

    When adipose-derived stem cells (ASCs) are retrieved from the stromal vascular portion of adipose tissue, a large amount of mature adipocytes are often discarded. However, by modified ceiling culture technique based on their buoyancy, mature adipocytes can be easily isolated from the adipose cell suspension and dedifferentiated into lipid-free fibroblast-like cells, named dedifferentiated fat (DFAT) cells. DFAT cells re-establish active proliferation ability and undertake multipotent capacities. Compared with ASCs and other adult stem cells, DFAT cells showed unique advantages in their abundance, isolation and homogeneity. In this concise review, the establishment and culture methods of DFAT cells are introduced and the current profiles of their cellular nature are summarized. Under proper induction culture in vitro or environment in vivo, DFAT cells could demonstrate adipogenic, osteogenic, chondrogenic and myogenic potentials. In angiogenic conditions, DFAT cells could exhibit perivascular characteristics and elicit neovascularization. Our preliminary findings also suggested the pericyte phenotype underlying such cell lineage, which supported a novel interpretation about the common origin of mesenchymal stem cells and tissue-specific stem cells within blood vessel walls. Current research on DFAT cells indicated that this alternative source of adult multipotent cells has great potential in tissue engineering and regenerative medicine. PMID:21789960

  16. Dedifferentiated fat cells: an alternative source of adult multipotent cells from the adipose tissues.

    PubMed

    Shen, Jie-fei; Sugawara, Atsunori; Yamashita, Joe; Ogura, Hideo; Sato, Soh

    2011-07-01

    When adipose-derived stem cells (ASCs) are retrieved from the stromal vascular portion of adipose tissue, a large amount of mature adipocytes are often discarded. However, by modified ceiling culture technique based on their buoyancy, mature adipocytes can be easily isolated from the adipose cell suspension and dedifferentiated into lipid-free fibroblast-like cells, named dedifferentiated fat (DFAT) cells. DFAT cells re-establish active proliferation ability and undertake multipotent capacities. Compared with ASCs and other adult stem cells, DFAT cells showed unique advantages in their abundance, isolation and homogeneity. In this concise review, the establishment and culture methods of DFAT cells are introduced and the current profiles of their cellular nature are summarized. Under proper induction culture in vitro or environment in vivo, DFAT cells could demonstrate adipogenic, osteogenic, chondrogenic and myogenic potentials. In angiogenic conditions, DFAT cells could exhibit perivascular characteristics and elicit neovascularization. Our preliminary findings also suggested the pericyte phenotype underlying such cell lineage, which supported a novel interpretation about the common origin of mesenchymal stem cells and tissue-specific stem cells within blood vessel walls. Current research on DFAT cells indicated that this alternative source of adult multipotent cells has great potential in tissue engineering and regenerative medicine.

  17. Haploidentical Stem Cell Transplantation in Adult Haematological Malignancies

    PubMed Central

    Parmesar, Kevon; Raj, Kavita

    2016-01-01

    Haematopoietic stem cell transplantation is a well-established treatment option for both hematological malignancies and nonmalignant conditions such as aplastic anemia and haemoglobinopathies. For those patients lacking a suitable matched sibling or matched unrelated donor, haploidentical donors are an alternative expedient donor pool. Historically, haploidentical transplantation led to high rates of graft rejection and GVHD. Strategies to circumvent these issues include T cell depletion and management of complications thereof or T replete transplants with GVHD prophylaxis. This review is an overview of these strategies and contemporaneous outcomes for hematological malignancies in adult haploidentical stem cell transplant recipients. PMID:27313619

  18. Mobilized adult pituitary stem cells contribute to endocrine regeneration in response to physiological demand.

    PubMed

    Rizzoti, Karine; Akiyama, Haruhiko; Lovell-Badge, Robin

    2013-10-03

    Pituitary hormone deficiencies, with Growth Hormone deficiency being most frequent (1 in 3,500-10,000 births), cause significant morbidity. Regeneration of missing endocrine cells would be a significant improvement over hormone replacement therapies, which incur side effects and do not mimic physiological secretion patterns. Recent in vitro studies have identified a population of adult pituitary progenitors that express the HMG box transcription factors SOX2 and SOX9. Here, we apply cell-lineage tracing analysis to demonstrate that SOX2- and SOX9-expressing progenitors can self-renew and give rise to endocrine cells in vivo, suggesting that they are tissue stem cells. Moreover, we show that they can become mobilized and differentiate into the appropriate endocrine cell types in response to physiological stress. Our results highlight the pituitary as a model for exploring how physiological changes influence stem cell behavior and suggest that manipulation of endogenous pituitary stem cells is a potential therapeutic strategy for pituitary deficiencies.

  19. 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

  20. Delivery of Mesenchymal Stem Cells in Chitosan/Collagen Microbeads for Orthopaedic Tissue Repair

    PubMed Central

    Wang, Limin; Rao, Rameshwar R.; Stegemann, Jan P.

    2013-01-01

    Microencapsulation and delivery of stem cells in biomaterials is a promising approach to repairing damaged tissue in a minimally invasive manner. An appropriate biomaterial niche can protect the embedded cells from the challenging environment in the host tissue, while also directing stem cell differentiation toward the desired lineage. In this study, adult human mesenchymal stem cells (MSC) were embedded in hydrogel microbeads consisting of chitosan and Type I collagen using an emulsification process. Glyoxal and β-glycerophosphate were used as physical and chemical crosslinkers to initiate co-polymerization of the matrix materials. The average size and size distribution of the microbeads could be varied by controlling the emulsification conditions. Spheroidal microbeads ranging in diameter from 82±19 to 290±78 μm were produced. Viability staining showed that MSC survived the encapsulation process (>90% viability), and spread inside the matrix over a period of 9 days in culture. Induced osteogenic differentiation using medium supplements showed that MSC increased gene expression of osterix and osteocalcin over time in culture, and also deposited calcium mineral. Bone sialoprotein and Type I collagen gene expression were not affected. Delivery of microbeads through standard needles at practically relevant flow rates did not adversely affect cell viability, and microbeads also could be easily molded into prescribed geometries for delivery. Such protein-based microbeads may have utility in orthopaedic tissue regeneration by allowing minimally invasive delivery of progenitor cells in microenvironments that are both protective and instructive. PMID:23571151

  1. Adipose tissue-derived stem cells in neural regenerative medicine.

    PubMed

    Yeh, Da-Chuan; Chan, Tzu-Min; Harn, Horng-Jyh; Chiou, Tzyy-Wen; Chen, Hsin-Shui; Lin, Zung-Sheng; Lin, Shinn-Zong

    2015-01-01

    Adipose tissue-derived stem cells (ADSCs) have two essential characteristics with regard to regenerative medicine: the convenient and efficient generation of large numbers of multipotent cells and in vitro proliferation without a loss of stemness. The implementation of clinical trials has prompted widespread concern regarding safety issues and has shifted research toward the therapeutic efficacy of stem cells in dealing with neural degeneration in cases such as stroke, amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease, Huntington's disease, cavernous nerve injury, and traumatic brain injury. Most existing studies have reported that cell therapies may be able to replenish lost cells and promote neuronal regeneration, protect neuronal survival, and play a role in overcoming permanent paralysis and loss of sensation and the recovery of neurological function. The mechanisms involved in determining therapeutic capacity remain largely unknown; however, this concept can still be classified in a methodical manner by citing current evidence. Possible mechanisms include the following: 1) the promotion of angiogenesis, 2) the induction of neuronal differentiation and neurogenesis, 3) reductions in reactive gliosis, 4) the inhibition of apoptosis, 5) the expression of neurotrophic factors, 6) immunomodulatory function, and 7) facilitating neuronal integration. In this study, several human clinical trials using ADSCs for neuronal disorders were investigated. It is suggested that ADSCs are one of the choices among various stem cells for translating into clinical application in the near future.

  2. [Radiotherapy of adult soft tissue sarcoma].

    PubMed

    Le Péchoux, C; Moureau-Zabotto, L; Llacer, C; Ducassou, A; Sargos, P; Sunyach, M P; Thariat, J

    2016-09-01

    Incidence of soft tissue sarcoma is low and requires multidisciplinary treatment in specialized centers. The objective of this paper is to report the state of the art regarding indications and treatment techniques of main soft tissue sarcoma localisations.

  3. The sexual identity of adult intestinal stem cells controls organ size and plasticity

    PubMed Central

    Hudry, Bruno; Khadayate, Sanjay; Miguel-Aliaga, Irene

    2016-01-01

    SUMMARY Sex differences in physiology and disease susceptibility are commonly attributed to developmental and/or hormonal factors, but there is increasing realisation that cell-intrinsic mechanisms play important and persistent roles1,2. Here we use the Drosophila melanogaster intestine to investigate the nature and significance of cellular sex in an adult somatic organ in vivo. We find that the adult intestinal epithelium is a cellular mosaic of different sex differentiation pathways, and displays extensive sex differences in expression of genes with roles in growth and metabolism. Cell-specific reversals of the sexual identity of adult intestinal stem cells uncover its key roles in controlling organ size, its reproductive plasticity and its response to genetically induced tumours. Unlike previous examples of sexually dimorphic somatic stem cell activity, the sex differences in intestinal stem cell behaviour arise from intrinsic mechanisms, which control cell cycle duration and involve a new doublesex- and fruitless-independent branch of the sex differentiation pathway downstream of transformer. Together, our findings indicate that the plasticity of an adult somatic organ is reversibly controlled by its sexual identity, imparted by a new mechanism that may be active in more tissues than previously recognised. PMID:26887495

  4. Identifying endogenous neural stem cells in the adult brain in vitro and in vivo: novel approaches.

    PubMed

    Rueger, Maria Adele; Androutsellis-Theotokis, Andreas

    2013-01-01

    In the 1960s, Joseph Altman reported that the adult mammalian brain is capable of generating new neurons. Today it is understood that some of these neurons are derived from uncommitted cells in the subventricular zone lining the lateral ventricles, and the dentate gyrus of the hippocampus. The first area generates new neuroblasts which migrate to the olfactory bulb, whereas hippocampal neurogenesis seems to play roles in particular types of learning and memory. A part of these uncommitted (immature) cells is able to divide and their progeny can generate all three major cell types of the nervous system: neurons, astrocytes, and oligodendrocytes; these properties define such cells as neural stem cells. Although the roles of these cells are not yet clear, it is accepted that they affect functions including olfaction and learning/memory. Experiments with insults to the central nervous system also show that neural stem cells are quickly mobilized due to injury and in various disorders by proliferating, and migrating to injury sites. This suggests a role of endogenous neural stem cells in disease. New pools of stem cells are being discovered, suggesting an even more important role for these cells. To understand these cells and to coax them to contribute to tissue repair it would be very useful to be able to image them in the living organism. Here we discuss advances in imaging approaches as well as new concepts that emerge from stem cell biology with emphasis on the interface between imaging and stem cells.

  5. From stem to roots: Tissue engineering in endodontics

    PubMed Central

    Kala, M.; Banthia, Priyank; Banthia, Ruchi

    2012-01-01

    The vitality of dentin-pulp complex is fundamental to the life of tooth and is a priority for targeting clinical management strategies. Loss of the tooth, jawbone or both, due to periodontal disease, dental caries, trauma or some genetic disorders, affects not only basic mouth functions but aesthetic appearance and quality of life. One novel approach to restore tooth structure is based on biology: regenerative endodontic procedure by application of tissue engineering. Regenerative endodontics is an exciting new concept that seeks to apply the advances in tissue engineering to the regeneration of the pulp-dentin complex. The basic logic behind this approach is that patient-specific tissue-derived cell populations can be used to functionally replace integral tooth tissues. The development of such ‘test tube teeth’ requires precise regulation of the regenerative events in order to achieve proper tooth size and shape, as well as the development of new technologies to facilitate these processes. This article provides an extensive review of literature on the concept of tissue engineering and its application in endodontics, providing an insight into the new developmental approaches on the horizon. Key words:Regenerative, tissue engineering, stem cells, scaffold. PMID:24558528

  6. Nano-regenerative medicine towards clinical outcome of stem cell and tissue engineering in humans

    PubMed Central

    Arora, Pooja; Sindhu, Annu; Dilbaghi, Neeraj; Chaudhury, Ashok; Rajakumar, Govindasamy; Rahuman, Abdul Abdul

    2012-01-01

    Nanotechnology is a fast growing area of research that aims to create nanomaterials or nanostructures development in stem cell and tissue-based therapies. Concepts and discoveries from the fields of bio nano research provide exciting opportunities of using stem cells for regeneration of tissues and organs. The application of nanotechnology to stem-cell biology would be able to address the challenges of disease therapeutics. This review covers the potential of nanotechnology approaches towards regenerative medicine. Furthermore, it focuses on current aspects of stem- and tissue-cell engineering. The magnetic nanoparticles-based applications in stem-cell research open new frontiers in cell and tissue engineering. PMID:22260258

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

    NASA Astrophysics Data System (ADS)

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

    2005-04-01

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

  8. Adult stem cell therapy and heart failure, 2000 to 2016: a systematic review

    PubMed Central

    Nguyen, Patricia K.; Rhee, June-Wha; Wu, Joseph C.

    2017-01-01

    Importance Stem cell therapy is a promising treatment strategy for patients with heart failure, which accounts for over 10% of deaths in the U.S. annually. Despite over a decade of research, further investigation is still needed to determine whether stem cell regenerative therapy is clinically effective and can be routinely implemented in clinical practice. Objective The purpose of this review is to describe the current progress in cardiac stem cell regenerative therapy using adult stem cells and highlight the merits and limitations of clinical trials performed to date. Evidence Review Information for this review was obtained through a search of PubMed and the Cochrane database for English language studies published between January 1, 2000 and April 20, 2016. Twenty-nine randomized clinical trials and 7 systematic reviews and meta-analyses were included in this review. Findings Although adult stem cells were once believed to have the ability to create new heart tissue or grow blood vessels, preclinical studies suggest instead that these cells release cardio-protective paracrine factors that activate endogenous pathways, leading to myocardial repair. Subsequent randomized controlled clinical trials, the majority of which used autologous bone marrow mononuclear cells, have found only a modest benefit in patients receiving stem cell therapy. The lack of a significant benefit may result from variations in trial methodology, discrepancies in reporting, and an over-reliance on surrogate endpoints. Conclusions and Relevance Although stem cell therapy for cardiovascular disease is not yet ready for routine clinical application, significant progress continues to be made. Physicians should be aware of the current status of this treatment so that they can better inform their patients who may be in search of alternative therapies. PMID:27557438

  9. Human adipose tissue stem cells: relevance in the pathophysiology of obesity and metabolic diseases and therapeutic applications.

    PubMed

    Cignarelli, Angelo; Perrini, Sebastio; Ficarella, Romina; Peschechera, Alessandro; Nigro, Pasquale; Giorgino, Francesco

    2012-12-10

    Stem cells are unique cells exhibiting self-renewing properties and the potential to differentiate into multiple specialised cell types. Totipotent or pluripotent stem cells are generally abundant in embryonic or fetal tissues, but the use of discarded embryos as sources of these cells raises challenging ethical problems. Adult stem cells can also differentiate into a wide variety of cell types. In particular, adult adipose tissue contains a pool of abundant and accessible multipotent stem cells, designated as adipose-derived stem cells (ASCs), that are able to replicate as undifferentiated cells, to develop as mature adipocytes and to differentiate into multiple other cell types along the mesenchymal lineage, including chondrocytes, myocytes and osteocytes, and also into cells of endodermal and neuroectodermal origin, including beta-cells and neurons, respectively. An impairment in the differentiation potential and biological functions of ASCs may contribute to the development of obesity and related comorbidities. In this review, we summarise different aspects of the ASCs with special reference to the isolation and characterisation of these cell populations, their relation to the biochemical features of the adipose tissue depot of origin and to the metabolic characteristics of the donor subject and discuss some prospective therapeutic applications.

  10. Simultaneous control of stemness and differentiation by the transcription factor Escargot in adult stem cells: How can we tease them apart?

    PubMed Central

    Loza-Coll, Mariano A.; Jones, D. Leanne

    2016-01-01

    ABSTRACT The homeostatic turnover of adult organs and their regenerative capacity following injury depend on a careful balance between stem cell self-renewal (to maintain or enlarge the stem cell pool) and differentiation (to replace lost tissue). We have recently characterized the role of the Drosophila Snail family transcription factor escargot (esg) in testis cyst stem cells (CySCs)1,2 and intestinal stem cells (ISCs). 3,4 CySCs mutant for esg are not maintained as stem cells, but they remain capable of differentiating normally along the cyst cell lineage. In contrast, esg mutant CySCs that give rise to a closely related lineage, the apical hub cells, cannot maintain hub cell identity. Similarly, Esg maintains stemness of ISCs while regulating the terminal differentiation of progenitor cells into absorptive enterocytes or secretory enteroendocrine cells. Therefore, our findings suggest that Esg may play a conserved and pivotal regulatory role in adult stem cells, controlling both their maintenance and terminal differentiation. Here we propose that this dual regulatory role is due to simultaneous control by Esg of overlapping genetic programs and discuss the exciting challenges and opportunities that lie ahead to explore the underlying mechanisms experimentally. PMID:27077690

  11. Planarian regeneration involves distinct stem cell responses to wounds and tissue absence.

    PubMed

    Wenemoser, Danielle; Reddien, Peter W

    2010-08-15

    Regeneration requires signaling from a wound site for detection of the wound and a mechanism that determines the nature of the injury to specify the appropriate regenerative response. Wound signals and tissue responses to wounds that elicit regeneration remain poorly understood. Planarians are able to regenerate from essentially any type of injury and present a novel system for the study of wound responses in regeneration initiation. Newly developed molecular and cellular tools now enable study of regeneration initiation using the planarian Schmidtea mediterranea. Planarian regeneration requires adult stem cells called neoblasts and amputation triggers two peaks in neoblast mitoses early in regeneration. We demonstrate that the first mitotic peak is a body-wide response to any injury and that a second, local, neoblast response is induced only when injury results in missing tissue. This second response was characterized by recruitment of neoblasts to wounds, even in areas that lack neoblasts in the intact animal. Subsequently, these neoblasts were induced to divide and differentiate near the wound, leading to formation of new tissue. We conclude that there exist two functionally distinct signaling phases of the stem cell wound response that distinguish between simple injury and situations that require the regeneration of missing tissue.

  12. Adipose tissue-derived stem cells as a therapeutic tool for cardiovascular disease

    PubMed Central

    Suzuki, Etsu; Fujita, Daishi; Takahashi, Masao; Oba, Shigeyoshi; Nishimatsu, Hiroaki

    2015-01-01

    Adipose tissue-derived stem cells (ADSCs) are adult stem cells that can be easily harvested from subcutaneous adipose tissue. Many studies have demonstrated that ADSCs differentiate into vascular endothelial cells (VECs), vascular smooth muscle cells (VSMCs), and cardiomyocytes in vitro and in vivo. However, ADSCs may fuse with tissue-resident cells and obtain the corresponding characteristics of those cells. If fusion occurs, ADSCs may express markers of VECs, VSMCs, and cardiomyocytes without direct differentiation into these cell types. ADSCs also produce a variety of paracrine factors such as vascular endothelial growth factor, hepatocyte growth factor, and insulin-like growth factor-1 that have proangiogenic and/or antiapoptotic activities. Thus, ADSCs have the potential to regenerate the cardiovascular system via direct differentiation into VECs, VSMCs, and cardiomyocytes, fusion with tissue-resident cells, and the production of paracrine factors. Numerous animal studies have demonstrated the efficacy of ADSC implantation in the treatment of acute myocardial infarction (AMI), ischemic cardiomyopathy (ICM), dilated cardiomyopathy, hindlimb ischemia, and stroke. Clinical studies regarding the use of autologous ADSCs for treating patients with AMI and ICM have recently been initiated. ADSC implantation has been reported as safe and effective so far. Therefore, ADSCs appear to be useful for the treatment of cardiovascular disease. However, the tumorigenic potential of ADSCs requires careful evaluation before their safe clinical application. PMID:26322185

  13. The effect of diabetes on the wound healing potential of adipose-tissue derived stem cells.

    PubMed

    Kim, Sue Min; Kim, Yun Ho; Jun, Young Joon; Yoo, Gyeol; Rhie, Jong Won

    2016-03-01

    To investigate whether diabetes mellitus affects the wound-healing-promoting potential of adipose tissue-derived stem cells, we designed a wound-healing model using diabetic mice. We compared the degree of wound healing between wounds treated with normal adipose tissue-derived stem cells and wounds treated with diabetic adipose tissue-derived stem cells. We evaluated the wound-healing rate, the epithelial tongue distance, the area of granulation tissue, the number of capillary and the number of Ki-67-stained cells. The wound-healing rate was significantly higher in the normal adipose tissue-derived stem cells group than in the diabetic adipose tissue-derived stem cells group; it was also significantly higher in the normal adipose tissue-derived stem cells group than in the control group. Although the diabetic adipose tissue-derived stem cells group showed a better wound-healing rate than the control group, the difference was not statistically significant. Similar trends were observed for the other parameters examined: re-epithelisation and keratinocyte proliferation; granulation tissue formation; and dermal regeneration. However, with regard to the number of capillary, diabetic adipose tissue-derived stem cells retained their ability to promote neovasculisation and angiogenesis. These results reflect the general impairment of the therapeutic potential of diabetic adipose tissue-derived stem cells in vivo.

  14. Leucine-rich repeat-containing G-protein-coupled receptors as markers of adult stem cells.

    PubMed

    Barker, Nick; Clevers, Hans

    2010-05-01

    Molecular markers are used to characterize and track adult stem cells. Colon cancer research has led to the identification of 2 related receptors, leucine-rich repeat-containing, G-protein-coupled receptors (Lgr)5 and Lgr6, that are expressed by small populations of cells in a variety of adult organs. Genetic mouse models have allowed the visualization, isolation, and genetic marking of Lgr5(+ve) and Lgr6(+ve) cells and provided evidence that they are stem cells. The Lgr5(+ve) cells were found to occupy locations not commonly associated with stem cells in the stomach, small intestine, colon, and hair follicles. A multipotent population of skin stem cells express Lgr6. Single Lgr5(+ve) stem cells from the small intestine and the stomach can be cultured into long-lived organoids. Further studies of these markers might reveal adult stem cell populations in additional tissues. Identification of the ligands for Lgr5 and 6 will help elucidate stem cell functions and modes of intracellular signaling.

  15. Spontaneous transformation of adult mesenchymal stem cells from cynomolgus macaques in vitro

    SciTech Connect

    Ren, Zhenhua; Wang, Jiayin; Zhu, Wanwan; Guan, Yunqian; Zou, Chunlin; Chen, Zhiguo; Zhang, Y. Alex

    2011-12-10

    Mesenchymal stem cells (MSCs) have shown potential clinical utility in cell therapy and tissue engineering, due to their ability to proliferate as well as to differentiate into multiple lineages, including osteogenic, adipogenic, and chondrogenic specifications. Therefore, it is crucial to assess the safety of MSCs while extensive expansion ex vivo is a prerequisite to obtain the cell numbers for cell transplantation. Here we show that MSCs derived from adult cynomolgus monkey can undergo spontaneous transformation following in vitro culture. In comparison with MSCs, the spontaneously transformed mesenchymal cells (TMCs) display significantly different growth pattern and morphology, reminiscent of the characteristics of tumor cells. Importantly, TMCs are highly tumorigenic, causing subcutaneous tumors when injected into NOD/SCID mice. Moreover, no multiple differentiation potential of TMCs is observed in vitro or in vivo, suggesting that spontaneously transformed adult stem cells may not necessarily turn into cancer stem cells. These data indicate a direct transformation of cynomolgus monkey MSCs into tumor cells following long-term expansion in vitro. The spontaneous transformation of the cultured cynomolgus monkey MSCs may have important implications for ongoing clinical trials and for models of oncogenesis, thus warranting a more strict assessment of MSCs prior to cell therapy. -- Highlights: Black-Right-Pointing-Pointer Spontaneous transformation of cynomolgus monkey MSCs in vitro. Black-Right-Pointing-Pointer Transformed mesenchymal cells lack multipotency. Black-Right-Pointing-Pointer Transformed mesenchymal cells are highly tumorigenic. Black-Right-Pointing-Pointer Transformed mesenchymal cells do not have the characteristics of cancer stem cells.

  16. Polarization birefringence measurements for characterizing the myocardium, including healthy, infarcted, and stem-cell-regenerated tissues

    NASA Astrophysics Data System (ADS)

    Wood, Michael F. G.; Ghosh, Nirmalya; Wallenburg, Marika A.; Li, Shu-Hong; Weisel, Richard D.; Wilson, Brian C.; Li, Ren-Ke; Vitkin, I. Alex

    2010-07-01

    Myocardial infarction leads to structural remodeling of the myocardium, in particular to the loss of cardiomyocytes due to necrosis and an increase in collagen with scar formation. Stem cell regenerative treatments have been shown to alter this remodeling process, resulting in improved cardiac function. As healthy myocardial tissue is highly fibrous and anisotropic, it exhibits optical linear birefringence due to the different refractive indices parallel and perpendicular to the fibers. Accordingly, changes in myocardial structure associated with infarction and treatment-induced remodeling will alter the anisotropy exhibited by the tissue. Polarization-based linear birefringence is measured on the myocardium of adult rat hearts after myocardial infarction and compared with hearts that had received mesenchymal stem cell treatment. Both point measurement and imaging data show a decrease in birefringence in the region of infarction, with a partial rebound back toward the healthy values following regenerative treatment with stem cells. These results demonstrate the ability of optical polarimetry to characterize the micro-organizational state of the myocardium via its measured anisotropy, and the potential of this approach for monitoring regenerative treatments of myocardial infarction.

  17. [Oro-maxillofacial bone tissue engineering combining biomaterials, stem cells, and gene therapy].

    PubMed

    Myon, L; Ferri, J; Chai, F; Blanchemain, N; Raoul, G

    2011-09-01

    Improvements have been made in regenerative medicine, due to the development of tissue engineering and cellular therapy. Bone regeneration is an ambitious project, leading to many applications involving skull, maxillofacial, and orthopaedic surgery. Scaffolds, stem cells, and signals support bone tissue engineering. The scaffold physical and chemical properties promote cell invasion, guide their differentiation, and enable signal transmission. Scaffold may be inorganic or organic. Their conception was improved by the use of new techniques: self-assembled nanofibres, electrospinning, solution-phase separation, micropatterned hydrogels, bioprinting, and rapid prototyping. Cellular biology processes allow us to choose between embryonic stem cells or adult stem cells for regenerative medicine. Finally, communication between cells and their environment is essential; they use various signals to do so. The study of signals and their transmission led to the discovery and the use of Bone Morphogenetic Protein (BMP). The development of cellular therapy led to the emergence of a specific field: gene therapy. It relies on viral vectors, which include: retroviruses, adenoviruses and adeno-associated vectors (AAV). Non-viral vectors include plasmids and lipoplex. Some BMP genes have successfully been transfected. The ability to control transfected cells and the capacity to combine and transfect many genes involved in osseous healing will improve gene therapy.

  18. Pericytes, integral components of adult hematopoietic stem cell niches.

    PubMed

    Sá da Bandeira, D; Casamitjana, J; Crisan, M

    2017-03-01

    The interest in perivascular cells as a niche for adult hematopoietic stem cells (HSCs) is significantly growing. In the adult bone marrow (BM), perivascular cells and HSCs cohabit. Among perivascular cells, pericytes are precursors of mesenchymal stem/stromal cells (MSCs) that are capable of differentiating into osteoblasts, adipocytes and chondrocytes. In situ, pericytes are recognised by their localisation to the abluminal side of the blood vessel wall and closely associated with endothelial cells, in combination with the expression of markers such as CD146, neural glial 2 (NG2), platelet derived growth factor receptor β (PDGFRβ), α-smooth muscle actin (α-SMA), nestin (Nes) and/or leptin receptor (LepR). However, not all pericytes share a common phenotype: different immunophenotypes can be associated with distinct mesenchymal features, including hematopoietic support. In adult BM, arteriolar and sinusoidal pericytes control HSC behaviour, maintenance, quiescence and trafficking through paracrine effects. Different groups identified and characterized hematopoietic supportive pericyte subpopulations using various markers and mouse models. In this review, we summarize recent work performed by others to understand the role of the perivascular niche in the biology of HSCs in adults, as well as their importance in the development of therapies.

  19. Evaluating alternative stem cell hypotheses for adult corneal epithelial maintenance

    PubMed Central

    West, John D; Dorà, Natalie J; Collinson, J Martin

    2015-01-01

    In this review we evaluate evidence for three different hypotheses that explain how the corneal epithelium is maintained. The limbal epithelial stem cell (LESC) hypothesis is most widely accepted. This proposes that stem cells in the basal layer of the limbal epithelium, at the periphery of the cornea, maintain themselves and also produce transient (or transit) amplifying cells (TACs). TACs then move centripetally to the centre of the cornea in the basal layer of the corneal epithelium and also replenish cells in the overlying suprabasal layers. The LESCs maintain the corneal epithelium during normal homeostasis and become more active to repair significant wounds. Second, the corneal epithelial stem cell (CESC) hypothesis postulates that, during normal homeostasis, stem cells distributed throughout the basal corneal epithelium, maintain the tissue. According to this hypothesis, LESCs are present in the limbus but are only active during wound healing. We also consider a third possibility, that the corneal epithelium is maintained during normal homeostasis by proliferation of basal corneal epithelial cells without any input from stem cells. After reviewing the published evidence, we conclude that the LESC and CESC hypotheses are consistent with more of the evidence than the third hypothesis, so we do not consider this further. The LESC and CESC hypotheses each have difficulty accounting for one main type of evidence so we evaluate the two key lines of evidence that discriminate between them. Finally, we discuss how lineage-tracing experiments have begun to resolve the debate in favour of the LESC hypothesis. Nevertheless, it also seems likely that some basal corneal epithelial cells can act as long-term progenitors if limbal stem cell function is compromised. Thus, this aspect of the CESC hypothesis may have a lasting impact on our understanding of corneal epithelial maintenance, even if it is eventually shown that stem cells are restricted to the limbus as proposed

  20. Identification of multipotent stem cells from adult dog periodontal ligament.

    PubMed

    Wang, Wen-Jun; Zhao, Yu-Ming; Lin, Bi-Chen; Yang, Jie; Ge, Li-Hong

    2012-08-01

    Periodontal diseases, which are characterized by destruction of the connective tissues responsible for restraining the teeth within the jaw, are the main cause of tooth loss. Periodontal regeneration mediated by human periodontal ligament stem cells (hPDLSCs) may offer an alternative strategy for the treatment of periodontal disease. Dogs are a widely used large-animal model for the study of periodontal-disease progression, tissue regeneration, and dental implants, but little attention has been paid to the identification of the cells involved in this species. This study aimed to characterize stem cells isolated from canine periodontal ligament (cPDLSCs). The cPDLSCs, like hPDLSCs, showed clonogenic capability and expressed the mesenchymal stem cell markers STRO-1, CD146, and CD105, but not CD34. After induction of osteogenesis, cPDLSCs showed calcium accumulation in vitro. Moreover, cPDLSCs also showed both adipogenic and chondrogenic potential. Compared with cell-free controls, more cementum/periodontal ligament-like structures were observed in CB-17/SCID mice into which cPDLSCs had been transplanted. These results suggest that cPDLSCs are clonogenic, highly proliferative, and have multidifferentiation potential, and that they could be used as a new cellular therapeutic approach to facilitate successful and more predictable regeneration of periodontal tissue using a canine model of periodontal disease.

  1. Human adipose CD34+ CD90+ stem cells and collagen scaffold constructs grafted in vivo fabricate loose connective and adipose tissues.

    PubMed

    Ferraro, Giuseppe A; De Francesco, Francesco; Nicoletti, Gianfranco; Paino, Francesca; Desiderio, Vincenzo; Tirino, Virginia; D'Andrea, Francesco

    2013-05-01

    Stem cell based therapies for the repair and regeneration of various tissues are of great interest for a high number of diseases. Adult stem cells, instead, are more available, abundant and harvested with minimally invasive procedures. In particular, mesenchymal stem cells (MSCs) are multi-potent progenitors, able to differentiate into bone, cartilage, and adipose tissues. Human adult adipose tissue seems to be the most abundant source of MSCs and, due to its easy accessibility; it is able to give a considerable amount of stem cells. In this study, we selected MSCs co-expressing CD34 and CD90 from adipose tissue. This stem cell population displayed higher proliferative capacity than CD34(-) CD90(-) cells and was able to differentiate in vitro into adipocytes (PPARγ(+) and adiponectin(+)) and endothelial cells (CD31(+) VEGF(+) Flk1(+)). In addition, in methylcellulose without VEGF, it formed a vascular network. The aim of this study was to investigate differentiation potential of human adipose CD34(+) /CD90(+) stem cells loaded onto commercial collagen sponges already used in clinical practice (Gingistat) both in vitro and in vivo. The results of this study clearly demonstrate that human adult adipose and loose connective tissues can be obtained in vivo, highlighting that CD34(+) /CD90 ASCs are extremely useful for regenerative medicine.

  2. Pituitary Cell Turnover: From Adult Stem Cell Recruitment through Differentiation to Death.

    PubMed

    Garcia-Lavandeira, Montserrat; Diaz-Rodriguez, Esther; Bahar, Dilek; Garcia-Rendueles, Angela R; Rodrigues, Joana S; Dieguez, Carlos; Alvarez, Clara V

    2015-01-01

    The recent demonstration using genetic tracing that in the adult pituitary stem cells are normally recruited from the niche in the marginal zone and differentiate into secretory cells in the adenopituitary has elegantly confirmed the proposal made when the pituitary stem cell niche was first discovered 5 years ago. Some of the early controversies have also been resolved. However, many questions remain, such as which are the markers that make a pituitary stem cell truly unique and the exact mechanisms that trigger recruitment from the niche. Little is known about the processes of commitment and differentiation once a stem cell has left the niche. Moreover, the acceptance that pituitary cells are renewed by stem cells implies the existence of regulated mechanisms of cell death in differentiated cells which must themselves be explained. The demonstration of an apoptotic pathway mediated by RET/caspase 3/Pit-1/Arf/p53 in normal somatotrophs is therefore an important step towards understanding how pituitary cell number is regulated. Further work will elucidate how the rates of the three processes of cell renewal, differentiation and apoptosis are balanced in tissue homeostasis after birth, but altered in pituitary hyperplasia in response to physiological stimuli such as puberty and lactation. Thus, we can aim to understand the mechanisms underlying human disease due to insufficient (hypopituitarism) or excess (pituitary tumor) cell numbers.

  3. Epimorphic regeneration approach to tissue replacement in adult mammals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Urodeles and fetal mammals are capable of impressive epimorphic regeneration in a variety of tissues, whereas the typical default response to injury in adult mammals consists of inflammation and scar tissue formation. One component of epimorphic regeneration is the recruitment of resident progenitor...

  4. Epidermal stem cells and skin tissue engineering in hair follicle regeneration

    PubMed Central

    Balañá, María Eugenia; Charreau, Hernán Eduardo; Leirós, Gustavo José

    2015-01-01

    The reconstitution of a fully organized and functional hair follicle from dissociated cells propagated under defined tissue culture conditions is a challenge still pending in tissue engineering. The loss of hair follicles caused by injuries or pathologies such as alopecia not only affects the patients’ psychological well-being, but also endangers certain inherent functions of the skin. It is then of great interest to find different strategies aiming to regenerate or neogenerate the hair follicle under conditions proper of an adult individual. Based upon current knowledge on the epithelial and dermal cells and their interactions during the embryonic hair generation and adult hair cycling, many researchers have tried to obtain mature hair follicles using different strategies and approaches depending on the causes of hair loss. This review summarizes current advances in the different experimental strategies to regenerate or neogenerate hair follicles, with emphasis on those involving neogenesis of hair follicles in adult individuals using isolated cells and tissue engineering. Most of these experiments were performed using rodent cells, particularly from embryonic or newborn origin. However, no successful strategy to generate human hair follicles from adult cells has yet been reported. This review identifies several issues that should be considered to achieve this objective. Perhaps the most important challenge is to provide three-dimensional culture conditions mimicking the structure of living tissue. Improving culture conditions that allow the expansion of specific cells while protecting their inductive properties, as well as methods for selecting populations of epithelial stem cells, should give us the necessary tools to overcome the difficulties that constrain human hair follicle neogenesis. An analysis of patent trends shows that the number of patent applications aimed at hair follicle regeneration and neogenesis has been increasing during the last decade. This

  5. Morphogenesis and tissue engineering of bone and cartilage: inductive signals, stem cells, and biomimetic biomaterials.

    PubMed

    Reddi, A H

    2000-08-01

    Morphogenesis is the developmental cascade of pattern formation, body plan establishment, and the architecture of mirror-image bilateral symmetry of many structures and asymmetry of some, culminating in the adult form. Tissue engineering is the emerging discipline of design and construction of spare parts for the human body to restore function based on principles of molecular developmental biology and morphogenesis governed by bioengineering. The three key ingredients for both morphogenesis and tissue engineering are inductive signals, responding stem cells, and the extracellular matrix. Among the many tissues in the human body, bone has considerable powers for regeneration and is a prototype model for tissue engineering based on morphogenesis. Implantation of demineralized bone matrix into subcutaneous sites results in local bone induction. This model mimics sequential limb morphogenesis and permitted the isolation of bone morphogens. Although it is traditional to study morphogenetic signals in embryos, bone morphogenetic proteins (BMPs), the inductive signals for bone, were isolated from demineralized bone matrix from adults. BMPs and related cartilage-derived morphogenetic proteins (CDMPs) initiate, promote, and maintain chondrogenesis and osteogenesis and have actions beyond bone. The symbiosis of bone inductive and conductive strategies are critical for tissue engineering, and is in turn governed by the context and biomechanics. The context is the microenvironment, consisting of extracellular matrix, which can be duplicated by biomimetic biomaterials such as collagens, hydroxyapatite, proteoglycans, and cell adhesion proteins including fibronectins. Thus, the rules of architecture for tissue engineering are an imitation of the laws of developmental biology and morphogenesis, and thus may be universal for all tissues, including bones and joints.

  6. Treatment of Bladder Dysfunction Using Stem Cell or Tissue Engineering Technique

    PubMed Central

    Kim, Jae Heon; Lee, Hong Jun

    2014-01-01

    Tissue engineering and stem cell transplantation are two important options that may help overcome limitations in the current treatment strategy for bladder dysfunction. Stem cell therapy holds great promise for treating pathophysiology, as well as for urological tissue engineering and regeneration. To date, stem cell therapy in urology has mainly focused on oncology and erectile dysfunction. The therapeutic potency of stem cells (SCs) was originally thought to derive from their ability to differentiate into various cell types including smooth muscle. The main mechanisms of SCs in reconstituting or restoring bladder function are migration, differentiation, and paracrine effects. Nowadays, paracrine effects of stem cells are thought to be more prominent because of their stimulating effects on stem cells and adjacent cells. Studies of stem cell therapy for bladder dysfunction have been limited to experimental models and have been less focused on tissue engineering for bladder regeneration. Bladder outlet obstruction is a representative model. Adipose-derived stem cells, bone marrow stem cells (BMSCs), and skeletal muscle-derived stem cells or muscle precursor cells are used for transplantation to treat bladder dysfunction. The aim of this study is to review stem cell therapy and updated tissue regeneration as treatments for bladder dysfunction and to provide the current status of stem cell therapy and tissue engineering for bladder dysfunction including its mechanisms and limitations. PMID:24741410

  7. Gap junction proteins: master regulators of the planarian stem cell response to tissue maintenance and injury.

    PubMed

    Peiris, T Harshani; Oviedo, Néstor J

    2013-01-01

    Gap junction (GJ) proteins are crucial mediators of cell-cell communication during embryogenesis, tissue regeneration and disease. GJ proteins form plasma membrane channels that facilitate passage of small molecules across cells and modulate signaling pathways and cellular behavior in different tissues. These properties have been conserved throughout evolution, and in most invertebrates GJ proteins are known as innexins. Despite their critical relevance for physiology and disease, the mechanisms by which GJ proteins modulate cell behavior are poorly understood. This review summarizes findings from recent work that uses planarian flatworms as a paradigm to analyze GJ proteins in the complexity of the whole organism. The planarian model allows access to a large pool of adult somatic stem cells (known as neoblasts) that support physiological cell turnover and tissue regeneration. Innexin proteins are present in planarians and play a fundamental role in controlling neoblast behavior. We discuss the possibility that GJ proteins participate as cellular sensors that inform neoblasts about local and systemic physiological demands. We believe that functional analyses of GJ proteins will bring a complementary perspective to studies that focus on the temporal expression of genes. Finally, integrating functional studies along with molecular genetics and epigenetic approaches would expand our understanding of cellular regulation in vivo and greatly enhance the possibilities for rationally modulating stem cell behavior in their natural environment. This article is part of a Special Issue entitled: The communicating junctions, roles and dysfunctions.

  8. Comparison of Characteristics of Human Amniotic Membrane and Human Adipose Tissue Derived Mesenchymal Stem Cells

    PubMed Central

    Dizaji Asl, Khadijeh; Shafaei, Hajar; Soleimani Rad, Jafar; Nozad, Hojjat Ollah

    2017-01-01

    BACKGROUND Mesenchymal stem cells (MSCs) are ideal candidates for treatment of diseases. Amniotic membranes are an inexpensive source of MSCs (AM-MSC) without any donor site morbidity in cell therapy. Adipose tissue derived stem cells (ASCs) are also suitable cells for cell therapy. There is discrepancy in CD271 expression among MSCs from different sources. In this study, the characteristics of AM-MSC and ASCs and CD271 expression were compared. METHODS Adult adipose tissue samples were obtained from patients undergoing elective surgical procedure, and samples of amniotic membrane were collected immediately after caesarean operation. After isolation and expansion of MSCs, the proliferation rate and viability of cells were evaluated through calculating DT and MTT assay. Expression of routine mesenchymal specific surface antigens of MSCs and CD271 was evaluated by flow cytometry for both types of cells. RESULTS The growth rate and viability of the MSCs from the amniotic membrane was significantly higher compared with the ASCs. The low expression of CD14 and CD45 indicated that AM-MSC and ASCs are non hematopoietic cells, and both cell types expressed high percentages of CD44, CD105. The results revealed that AM-MSC and ASCs expressed no CD271 on their surfaces. CONCLUSION This study showed that amniotic membrane is a suitable cell source for cell therapy, and CD271 is a negative marker for MSCs identification from amniotic membrane and adipose tissue. PMID:28289611

  9. Concise Review: Human Dermis as an Autologous Source of Stem Cells for Tissue Engineering and Regenerative Medicine

    PubMed Central

    Vapniarsky, Natalia; Arzi, Boaz; Hu, Jerry C.; Nolta, Jan A.

    2015-01-01

    The exciting potential for regenerating organs from autologous stem cells is on the near horizon, and adult dermis stem cells (DSCs) are particularly appealing because of the ease and relative minimal invasiveness of skin collection. A substantial number of reports have described DSCs and their potential for regenerating tissues from mesenchymal, ectodermal, and endodermal lineages; however, the exact niches of these stem cells in various skin types and their antigenic surface makeup are not yet clearly defined. The multilineage potential of DSCs appears to be similar, despite great variability in isolation and in vitro propagation methods. Despite this great potential, only limited amounts of tissues and clinical applications for organ regeneration have been developed from DSCs. This review summarizes the literature on DSCs regarding their niches and the specific markers they express. The concept of the niches and the differentiation capacity of cells residing in them along particular lineages is discussed. Furthermore, the advantages and disadvantages of widely used methods to demonstrate lineage differentiation are considered. In addition, safety considerations and the most recent advancements in the field of tissue engineering and regeneration using DSCs are discussed. This review concludes with thoughts on how to prospectively approach engineering of tissues and organ regeneration using DSCs. Our expectation is that implementation of the major points highlighted in this review will lead to major advancements in the fields of regenerative medicine and tissue engineering. Significance Autologous dermis-derived stem cells are generating great excitement and efforts in the field of regenerative medicine and tissue engineering. The substantial impact of this review lies in its critical coverage of the available literature and in providing insight regarding niches, characteristics, and isolation methods of stem cells derived from the human dermis. Furthermore, it

  10. Immune Influence on Adult Neural Stem Cell Regulation and Function

    PubMed Central

    Carpentier, Pamela A.; Palmer, Theo D.

    2009-01-01

    Neural stem cells (NSCs) lie at the heart of central nervous system development and repair, and deficiency or dysregulation of NSCs or their progeny can have significant consequences at any stage of life. Immune signaling is emerging as one of the influential variables that define resident NSC behavior. Perturbations in local immune signaling accompany virtually every injury or disease state and signaling cascades that mediate immune activation, resolution, or chronic persistence influence resident stem and progenitor cells. Some aspects of immune signaling are beneficial, promoting intrinsic plasticity and cell replacement, while others appear to inhibit the very type of regenerative response that might restore or replace neural networks lost in injury or disease. Here we review known and speculative roles that immune signaling plays in the postnatal and adult brain, focusing on how environments encountered in disease or injury may influence the activity and fate of endogenous or transplanted NSCs. PMID:19840551

  11. Retentive multipotency of adult dorsal root ganglia stem cells.

    PubMed

    Singh, Rabindra P; Cheng, Ying-Hua; Nelson, Paul; Zhou, Feng C

    2009-01-01

    Preservation of neural stem cells (NSCs) in the adult peripheral nervous system (PNS) has recently been confirmed. However, it is not clear whether peripheral NSCs possess predestined, bona fide phenotypes or a response to innate developmental cues. In this study, we first demonstrated the longevity, multipotency, and high fidelity of sensory features of postmigrating adult dorsal root ganglia (aDRG) stem cells. Derived from aDRG and after 4-5 years in culture without dissociating, the aDRG NSCs were found capable of proliferation, expressing neuroepithelial, neuronal, and glial markers. Remarkably, these aDRG NSCs expressed sensory neuronal markers vesicular glutamate transporter 2 (VGluT2--glutamate terminals), transient receptor potential vanilloid 1 (TrpV1--capsaicin sensitive), phosphorylated 200 kDa neurofilaments (pNF200--capsaicin insensitive, myelinated), and the serotonin transporter (5-HTT), which normally is transiently expressed in developing DRG. Furthermore, in response to neurotrophins, the aDRG NSCs enhanced TrpV1 expression upon exposure to nerve growth factor (NGF), but not to brain-derived neurotrophic factor (BDNF). On the contrary, BDNF increased the expression of NeuN. Third, the characterization of aDRG NSCs was demonstrated by transplantation of red fluorescent-expressing aDRG NSCs into injured spinal cord. These cells expressed nestin, Hu, and beta-III-tubulin (immature neuronal markers), GFAP (astrocyte marker) as well as sensory neural marker TrpV1 (capsaicin sensitive) and pNF200 (mature, capsaicin insensitive, myelinated). Our results demonstrated that the postmigrating neural crest adult DRG stem cells not only preserved their multipotency but also were retentive in sensory potency despite the age and long-term ex vivo status.

  12. Endometrial adult/progenitor stem cells: pathogenetic theory and new antiangiogenic approach for endometriosis therapy.

    PubMed

    Pittatore, G; Moggio, A; Benedetto, C; Bussolati, B; Revelli, A

    2014-03-01

    The cyclical arrival of endometrial cells into the abdominal cavity through retrograde flux at menstruation represents the etiopathogenetic basis of endometriosis. The endometrium has peculiar regenerative properties linked to the presence of adult stem cells similar to mesenchymal stem cells (MSCs). Once in the abdominal cavity, these MSCs could proliferate, invade, and differentiate into endometrial cells, finally generating ectopic implants. As only differentiated endometrial cells, and not endometrial MSCs, possess steroid hormone receptors, MSCs could be responsible for the high rate of persistence/recurrence of the disease after hypoestrogenism-inducing therapies. Even angiogenesis promoted by MSCs could play an important role, as survival and proliferation of endometriotic tissue depend on the formation of new blood vessels. Inhibition of angiogenesis represents, in fact, a new, promising therapeutic approach for the disease. Further, medications directly targeting endometriosis MSCs could be effective, alone or in association with hormonal treatments, in increasing the success of medical treatment.

  13. Inductive interactions mediated by interplay of asymmetric signalling underlie development of adult haematopoietic stem cells

    PubMed Central

    Souilhol, Céline; Gonneau, Christèle; Lendinez, Javier G.; Batsivari, Antoniana; Rybtsov, Stanislav; Wilson, Heather; Morgado-Palacin, Lucia; Hills, David; Taoudi, Samir; Antonchuk, Jennifer; Zhao, Suling; Medvinsky, Alexander

    2016-01-01

    During embryonic development, adult haematopoietic stem cells (HSCs) emerge preferentially in the ventral domain of the aorta in the aorta–gonad–mesonephros (AGM) region. Several signalling pathways such as Notch, Wnt, Shh and RA are implicated in this process, yet how these interact to regulate the emergence of HSCs has not previously been described in mammals. Using a combination of ex vivo and in vivo approaches, we report here that stage-specific reciprocal dorso–ventral inductive interactions and lateral input from the urogenital ridges are required to drive HSC development in the aorta. Our study strongly suggests that these inductive interactions in the AGM region are mediated by the interplay between spatially polarized signalling pathways. Specifically, Shh produced in the dorsal region of the AGM, stem cell factor in the ventral and lateral regions, and BMP inhibitory signals in the ventral tissue are integral parts of the regulatory system involved in the development of HSCs. PMID:26952187

  14. Stem and stromal cell reconstitution of lethally irradiated mice following transplantation of hematopoietic tissue from donors of various ages

    SciTech Connect

    Schmidt, C.M.; Doran, G.A.; Crouse, D.A.; Sharp, J.G.

    1987-10-01

    If the limited life span of hematopoietic tissues in vitro is due to a finite proliferative capacity of individual stem cells, one might expect tissues of young donors to possess a greater proliferative capacity and to contain a larger population of primitive stem cells than those of older donors. To test this hypothesis, we used 12- and 8-day spleen colony formation (CFU-s) to assay more and less primitive stem cell subpopulations of three murine hematopoietic tissues: fetal liver (FL) and weanling (WBM) and adult (ABM) bone marrow. Subsequently, the same assays and a stromal cell assay were performed on the bone marrow from groups of lethally irradiated mice reconstituted with these tissues. Comparison of the CFU-s content of the donor tissues revealed that FL contained a significantly greater proportion of primitive stem cells as evidenced by a (Day 12):(Day 8) CFU-s ratio of 3.0 +/- 1.0 as compared to 0.9 +/- 0.1 for WBM and ABM. In addition, at 21 weeks post-transplantation the CFU-s/femur values of the FL reconstituted group were significantly greater than those of the ABM and WBM reconstituted groups. These results suggest that fetal hematopoietic tissue contains a greater proportion of primitive stem cells and has a greater proliferative potential than hematopoietic tissue from older donors. No differences were seen in stromal cell reconstitution of the three experimental groups. In all cases, assayable fibroblast colony forming cells (CFU-f) remained at 20-40% of control values, even at 21 weeks postreconstitution.

  15. Promising Therapeutic Strategies for Mesenchymal Stem Cell-Based Cardiovascular Regeneration: From Cell Priming to Tissue Engineering

    PubMed Central

    Ji, Seung Taek; Yun, Jisoo

    2017-01-01

    The primary cause of death among chronic diseases worldwide is ischemic cardiovascular diseases, such as stroke and myocardial infarction. Recent evidence indicates that adult stem cell therapies involving cardiovascular regeneration represent promising strategies to treat cardiovascular diseases. Owing to their immunomodulatory properties and vascular repair capabilities, mesenchymal stem cells (MSCs) are strong candidate therapeutic stem cells for use in cardiovascular regeneration. However, major limitations must be overcome, including their very low survival rate in ischemic lesion. Various attempts have been made to improve the poor survival and longevity of engrafted MSCs. In order to develop novel therapeutic strategies, it is necessary to first identify stem cell modulators for intracellular signal triggering or niche activation. One promising therapeutic strategy is the priming of therapeutic MSCs with stem cell modulators before transplantation. Another is a tissue engineering-based therapeutic strategy involving a cell scaffold, a cell-protein-scaffold architecture made of biomaterials such as ECM or hydrogel, and cell patch- and 3D printing-based tissue engineering. This review focuses on the current clinical applications of MSCs for treating cardiovascular diseases and highlights several therapeutic strategies for promoting the therapeutic efficacy of MSCs in vitro or in vivo from cell priming to tissue engineering strategies, for use in cardiovascular regeneration. PMID:28303152

  16. The Neurovascular Properties of Dental Stem Cells and Their Importance in Dental Tissue Engineering

    PubMed Central

    Ratajczak, Jessica; Bronckaers, Annelies; Dillen, Yörg; Gervois, Pascal; Vangansewinkel, Tim; Driesen, Ronald B.; Wolfs, Esther; Lambrichts, Ivo

    2016-01-01

    Within the field of tissue engineering, natural tissues are reconstructed by combining growth factors, stem cells, and different biomaterials to serve as a scaffold for novel tissue growth. As adequate vascularization and innervation are essential components for the viability of regenerated tissues, there is a high need for easily accessible stem cells that are capable of supporting these functions. Within the human tooth and its surrounding tissues, different stem cell populations can be distinguished, such as dental pulp stem cells, stem cells from human deciduous teeth, stem cells from the apical papilla, dental follicle stem cells, and periodontal ligament stem cells. Given their straightforward and relatively easy isolation from extracted third molars, dental stem cells (DSCs) have become an attractive source of mesenchymal-like stem cells. Over the past decade, there have been numerous studies supporting the angiogenic, neuroprotective, and neurotrophic effects of the DSC secretome. Together with their ability to differentiate into endothelial cells and neural cell types, this makes DSCs suitable candidates for dental tissue engineering and nerve injury repair. PMID:27688777

  17. Differentiated human stem cells resemble fetal, not adult, β cells.

    PubMed

    Hrvatin, Sinisa; O'Donnell, Charles W; Deng, Francis; Millman, Jeffrey R; Pagliuca, Felicia Walton; DiIorio, Philip; Rezania, Alireza; Gifford, David K; Melton, Douglas A

    2014-02-25

    Human pluripotent stem cells (hPSCs) have the potential to generate any human cell type, and one widely recognized goal is to make pancreatic β cells. To this end, comparisons between differentiated cell types produced in vitro and their in vivo counterparts are essential to validate hPSC-derived cells. Genome-wide transcriptional analysis of sorted insulin-expressing (INS(+)) cells derived from three independent hPSC lines, human fetal pancreata, and adult human islets points to two major conclusions: (i) Different hPSC lines produce highly similar INS(+) cells and (ii) hPSC-derived INS(+) (hPSC-INS(+)) cells more closely resemble human fetal β cells than adult β cells. This study provides a direct comparison of transcriptional programs between pure hPSC-INS(+) cells and true β cells and provides a catalog of genes whose manipulation may convert hPSC-INS(+) cells into functional β cells.

  18. Positional identity of adult stem cells in salamander limb regeneration.

    PubMed

    Kumar, Anoop; Gates, Phillip B; Brockes, Jeremy P

    2007-01-01

    Limb regeneration in larval and adult salamanders proceeds from a mound of mesenchymal stem cells called the limb blastema. The blastema gives rise just to those structures distal to its level of origin, and this property of positional identity is reset to more proximal values by treatment with retinoic acid. We have identified a cell surface protein, called Prod1/CD59, which appears to be a determinant of proximodistal identity. Prod1 is expressed in an exponential gradient in an adult limb as determined by detection of both mRNA and immunoreactive protein. Prod1 protein is up-regulated after treatment of distal blastemas with RA and this is particularly marked in cells of the dermis. These cells have previously been implicated in pattern formation during limb regeneration.

  19. Generation of tissue-engineered small intestine using embryonic stem cell-derived human intestinal organoids

    PubMed Central

    Finkbeiner, Stacy R.; Freeman, Jennifer J.; Wieck, Minna M.; El-Nachef, Wael; Altheim, Christopher H.; Tsai, Yu-Hwai; Huang, Sha; Dyal, Rachel; White, Eric S.; Grikscheit, Tracy C.; Teitelbaum, Daniel H.; Spence, Jason R.

    2015-01-01

    ABSTRACT Short bowel syndrome (SBS) is characterized by poor nutrient absorption due to a deficit of healthy intestine. Current treatment practices rely on providing supportive medical therapy with parenteral nutrition; while life saving, such interventions are not curative and are still associated with significant co-morbidities. As approaches to lengthen remaining intestinal tissue have been met with only limited success and intestinal transplants have poor survival outcomes, new approaches to treating SBS are necessary. Human intestine derived from embryonic stem cells (hESCs) or induced pluripotent stem cells (iPSCs), called human intestinal organoids (HIOs), have the potential to offer a personalized and scalable source of intestine for regenerative therapies. However, given that HIOs are small three-dimensional structures grown in vitro, methods to generate usable HIO-derived constructs are needed. We investigated the ability of hESCs or HIOs to populate acellular porcine intestinal matrices and artificial polyglycolic/poly L lactic acid (PGA/PLLA) scaffolds, and examined the ability of matrix/scaffolds to thrive when transplanted in vivo. Our results demonstrate that the acellular matrix alone is not sufficient to instruct hESC differentiation towards an endodermal or intestinal fate. We observed that while HIOs reseed acellular porcine matrices in vitro, the HIO-reseeded matrices do not thrive when transplanted in vivo. In contrast, HIO-seeded PGA/PLLA scaffolds thrive in vivo and develop into tissue that looks nearly identical to adult human intestinal tissue. Our results suggest that HIO-seeded PGA/PLLA scaffolds are a promising avenue for developing the mucosal component of tissue engineered human small intestine, which need to be explored further to develop them into fully functional tissue. PMID:26459240

  20. Generation of tissue-engineered small intestine using embryonic stem cell-derived human intestinal organoids.

    PubMed

    Finkbeiner, Stacy R; Freeman, Jennifer J; Wieck, Minna M; El-Nachef, Wael; Altheim, Christopher H; Tsai, Yu-Hwai; Huang, Sha; Dyal, Rachel; White, Eric S; Grikscheit, Tracy C; Teitelbaum, Daniel H; Spence, Jason R

    2015-10-12

    Short bowel syndrome (SBS) is characterized by poor nutrient absorption due to a deficit of healthy intestine. Current treatment practices rely on providing supportive medical therapy with parenteral nutrition; while life saving, such interventions are not curative and are still associated with significant co-morbidities. As approaches to lengthen remaining intestinal tissue have been met with only limited success and intestinal transplants have poor survival outcomes, new approaches to treating SBS are necessary. Human intestine derived from embryonic stem cells (hESCs) or induced pluripotent stem cells (iPSCs), called human intestinal organoids (HIOs), have the potential to offer a personalized and scalable source of intestine for regenerative therapies. However, given that HIOs are small three-dimensional structures grown in vitro, methods to generate usable HIO-derived constructs are needed. We investigated the ability of hESCs or HIOs to populate acellular porcine intestinal matrices and artificial polyglycolic/poly L lactic acid (PGA/PLLA) scaffolds, and examined the ability of matrix/scaffolds to thrive when transplanted in vivo. Our results demonstrate that the acellular matrix alone is not sufficient to instruct hESC differentiation towards an endodermal or intestinal fate. We observed that while HIOs reseed acellular porcine matrices in vitro, the HIO-reseeded matrices do not thrive when transplanted in vivo. In contrast, HIO-seeded PGA/PLLA scaffolds thrive in vivo and develop into tissue that looks nearly identical to adult human intestinal tissue. Our results suggest that HIO-seeded PGA/PLLA scaffolds are a promising avenue for developing the mucosal component of tissue engineered human small intestine, which need to be explored further to develop them into fully functional tissue.

  1. The Jak-STAT target Chinmo prevents sex transformation of adult stem cells in the Drosophila testis niche

    PubMed Central

    Ma, Qing; Wawersik, Matthew; Matunis, Erika L.

    2014-01-01

    Local signals maintain adult stem cells in many tissues. Whether the sexual identity of adult stem cells must also be maintained was not known. In the adult Drosophila testis niche, local Jak-STAT signaling promotes somatic cyst stem cell (CySC) renewal through several effectors, including the putative transcription factor Chronologically inappropriate morphogenesis (Chinmo). Here, we find that Chinmo also prevents feminization of CySCs. Chinmo promotes expression of the canonical male sex determination factor DoublesexM (DsxM) within CySCs and their progeny, and ectopic expression of DsxM in the CySC lineage partially rescues the chinmo sex transformation phenotype, placing Chinmo upstream of DsxM. The Dsx homologue DMRT1 prevents the male-to female conversion of differentiated somatic cells in the adult mammalian testis, but its regulation is not well understood. Our work indicates that sex maintenance occurs in adult somatic stem cells, and that this highly conserved process is governed by effectors of niche signals. PMID:25453558

  2. Adult stem cells for cardiac repair: a choice between skeletal myoblasts and bone marrow stem cells.

    PubMed

    Ye, Lei; Haider, Husnain Kh; Sim, Eugene K W

    2006-01-01

    The real promise of a stem cell-based approach for cardiac regeneration and repair lies in the promotion of myogenesis and angiogenesis at the site of the cell graft to achieve both structural and functional benefits. Despite all of the progress and promise in this field, many unanswered questions remain; the answers to these questions will provide the much-needed breakthrough to harness the real benefits of cell therapy for the heart in the clinical perspective. One of the major issues is the choice of donor cell type for transplantation. Multiple cell types with varying potentials have been assessed for their ability to repopulate the infarcted myocardium; however, only the adult stem cells, that is, skeletal myoblasts (SkM) and bone marrow-derived stem cells (BMC), have been translated from the laboratory bench to clinical use. Which of these two cell types will provide the best option for clinical application in heart cell therapy remains arguable. With results pouring in from the long-term follow-ups of previously conducted phase I clinical studies, and with the onset of phase II clinical trials involving larger population of patients, transplantation of stem cells as a sole therapy without an adjunct conventional revascularization procedure will provide a deeper insight into the effectiveness of this approach. The present article discusses the pros and cons of using SkM and BMC individually or in combination for cardiac repair, and critically analyzes the progress made with each cell type.

  3. Engineering bone tissue substitutes from human induced pluripotent stem cells.

    PubMed

    de Peppo, Giuseppe Maria; Marcos-Campos, Iván; Kahler, David John; Alsalman, Dana; Shang, Linshan; Vunjak-Novakovic, Gordana; Marolt, Darja

    2013-05-21

    Congenital defects, trauma, and disease can compromise the integrity and functionality of the skeletal system to the extent requiring implantation of bone grafts. Engineering of viable bone substitutes that can be personalized to meet specific clinical needs represents a promising therapeutic alternative. The aim of our study was to evaluate the utility of human-induced pluripotent stem cells (hiPSCs) for bone tissue engineering. We first induced three hiPSC lines with different tissue and reprogramming backgrounds into the mesenchymal lineages and used a combination of differentiation assays, surface antigen profiling, and global gene expression analysis to identify the lines exhibiting strong osteogenic differentiation potential. We then engineered functional bone substitutes by culturing hiPSC-derived mesenchymal progenitors on osteoconductive scaffolds in perfusion bioreactors and confirmed their phenotype stability in a subcutaneous implantation model for 12 wk. Molecular analysis confirmed that the maturation of bone substitutes in perfusion bioreactors results in global repression of cell proliferation and an increased expression of lineage-specific genes. These results pave the way for growing patient-specific bone substitutes for reconstructive treatments of the skeletal system and for constructing qualified experimental models of development and disease.

  4. Heterochromatin protein 1 promotes self-renewal and triggers regenerative proliferation in adult stem cells.

    PubMed

    Zeng, An; Li, Yong-Qin; Wang, Chen; Han, Xiao-Shuai; Li, Ge; Wang, Jian-Yong; Li, Dang-Sheng; Qin, Yong-Wen; Shi, Yufang; Brewer, Gary; Jing, Qing

    2013-04-29

    Adult stem cells (ASCs) capable of self-renewal and differentiation confer the potential of tissues to regenerate damaged parts. Epigenetic regulation is essential for driving cell fate decisions by rapidly and reversibly modulating gene expression programs. However, it remains unclear how epigenetic factors elicit ASC-driven regeneration. In this paper, we report that an RNA interference screen against 205 chromatin regulators identified 12 proteins essential for ASC function and regeneration in planarians. Surprisingly, the HP1-like protein SMED-HP1-1 (HP1-1) specifically marked self-renewing, pluripotent ASCs, and HP1-1 depletion abrogated self-renewal and promoted differentiation. Upon injury, HP1-1 expression increased and elicited increased ASC expression of Mcm5 through functional association with the FACT (facilitates chromatin transcription) complex, which consequently triggered proliferation of ASCs and initiated blastema formation. Our observations uncover an epigenetic network underlying ASC regulation in planarians and reveal that an HP1 protein is a key chromatin factor controlling stem cell function. These results provide important insights into how epigenetic mechanisms orchestrate stem cell responses during tissue regeneration.

  5. From adult stem cells to cancer stem cells: Oct-4 Gene, cell-cell communication, and hormones during tumor promotion.

    PubMed

    Trosko, James E

    2006-11-01

    Carcinogenesis is characterized by "initiation," "promotion," and "progression" phases. The "stem cell theory" and "de-differentiation" theories are used to explain the origin of cancer. Growth control for stem cells, which lack functional gap junctional intercellular communication (GJIC), involves negative soluble or niche factors, while for progenitor cells, it involves GJIC. Tumor promoters, hormones, and growth factors inhibit GJIC reversibly. Oncogenes stably inhibit GJIC. Cancer cells, which lack growth control and the ability to terminally differentiate and to apoptose, lack GJIC. The Oct3/4 gene, a POU (Pit-Oct-Unc) family of transcription factors was thought to be expressed only in embryonic stem cells and in tumor cells. With the availability of normal adult human stem cells, tests for the expression of Oct3/4 gene and the stem cell theory in human carcinogenesis became possible. Human breast, liver, pancreas, kidney, mesenchyme, and gastric stem cells, HeLa and MCF-7 cells, and canine tumors were tested with antibodies and polymerase chain reaction (PCR) primers for Oct3/4. Adult human breast stem cells, immortalized nontumorigenic and tumor cell lines, but not the normal differentiated cells, expressed Oct3/4. Adult human differentiated cells lose their Oct-4 expression. Oct3/4 is expressed in a few cells found in the basal layer of human skin epidermis. The data demonstrate that normal adult stem cells and cancer stem cells maintain expression of Oct3/4, consistent with the stem cell hypothesis of carcinogenesis. These Oct-4 positive cells might represent the "cancer stem cells." A strategy to target "cancer stem cells" is to suppress the Oct-4 gene in order to cause the cells to differentiate.

  6. Clonogenic neoblasts are pluripotent adult stem cells that underlie planarian regeneration.

    PubMed

    Wagner, Daniel E; Wang, Irving E; Reddien, Peter W

    2011-05-13

    Pluripotent cells in the embryo can generate all cell types, but lineage-restricted cells are generally thought to replenish adult tissues. Planarians are flatworms and regenerate from tiny body fragments, a process requiring a population of proliferating cells (neoblasts). Whether regeneration is accomplished by pluripotent cells or by the collective activity of multiple lineage-restricted cell types is unknown. We used ionizing radiation and single-cell transplantation to identify neoblasts that can form large descendant-cell colonies in vivo. These clonogenic neoblasts (cNeoblasts) produce cells that differentiate into neuronal, intestinal, and other known postmitotic cell types and are distributed throughout the body. Single transplanted cNeoblasts restored regeneration in lethally irradiated hosts. We conclude that broadly distributed, adult pluripotent stem cells underlie the remarkable regenerative abilities of planarians.

  7. Chondrogenic induction of human mesenchymal stem cells using combined growth factors for cartilage tissue engineering.

    PubMed

    Bosetti, Michela; Boccafoschi, Francesca; Leigheb, Massimiliano; Bianchi, Andrea E; Cannas, Mario

    2012-03-01

    The objective of this study was to evaluate whether growth factors (FGF-2, FGF-4 and FGF-6) used alone or in combination with TGFβ2 are able to increase the proliferation and induce the differentiation of human bone marrow mesenchymal stem cells (hMSCs) to chondrocytes, with a view to using them in cartilage tissue engineering. Cells cultured in monolayer, used to test the activity of the growth factors on cell proliferation, showed that a combination of FGFs with TGFβ2 increases cell proliferation compared to cells cultured in control medium or in the presence of growth factors alone. The chondrogenic potential, evaluated in three-dimensional (3D) cell aggregates, showed that FGF-2 and FGF-6, when used in combination with TGFβ2 increased the size and glycosaminoglycan content of the cell aggregates without increasing cell number. Extracellular matrix (ECM) also showed higher collagen type II immunoreactivity, which was particularly evident in an area similar to a germinative pole that was observed only in pellets cultured with FGF-2 and FGF-6 combined with TGFβ2, or in pellets cultured with FGF-2 alone. Moreover, the RT-PCR assay has highlighted an increased expression of collagen type II and Sox9, used as gene markers for chondrogenesis. We can conclude that combinations of FGF-2 or FGF-6 with TGFβ2 may provide a novel tool to induce the differentiation of adult human mesenchymal stem cells for applications in cartilage tissue engineering.

  8. Harnessing the potential of adult cardiac stem cells: lessons from haematopoiesis, the embryo and the niche.

    PubMed

    Balmer, Gemma M; Riley, Paul R

    2012-10-01

    Across biomedicine, there is a major drive to develop stem cell (SC) treatments for debilitating diseases. Most effective treatments restore an embryonic phenotype to adult SCs. This has led to two emerging paradigms in SC biology: the application of developmental biology studies and the manipulation of the SC niche. Developmental studies can reveal how SCs are orchestrated to build organs, the understanding of which is important in order to instigate tissue repair in the adult. SC niche studies can reveal cues that maintain SC 'stemness' and how SCs may be released from the constraints of the niche to differentiate and repopulate a 'failing' organ. The haematopoietic system provides an exemplar whereby characterisation of the blood lineages during development and the bone marrow niche has resulted in therapeutics now routinely used in the clinic. Ischaemic heart disease is a major cause of morbidity and mortality in humans and the question remains as to whether these principles can be applied to the heart, in order to exploit the potential of adult SCs for use in cardiovascular repair and regeneration.

  9. Diabetic human adipose tissue-derived mesenchymal stem cells fail to differentiate in functional adipocytes.

    PubMed

    Barbagallo, Ignazio; Li Volti, Giovanni; Galvano, Fabio; Tettamanti, Guido; Pluchinotta, Francesca R; Bergante, Sonia; Vanella, Luca

    2016-11-30

    Adipose tissue dysfunction represents a hallmark of diabetic patients and is a consequence of the altered homeostasis of this tissue. Mesenchymal stem cells (MSCs) and their differentiation into adipocytes contribute significantly in maintaining the mass and function of adult adipose tissue. The aim of this study was to evaluate the differentiation of MSCs from patients suffering type 2 diabetes (dASC) and how such process results in hyperplasia or rather a stop of adipocyte turnover resulting in hypertrophy of mature adipocytes. Our results showed that gene profile of all adipogenic markers is not expressed in diabetic cells after differentiation indicating that diabetic cells fail to differentiate into adipocytes. Interestingly, delta like 1, peroxisome proliferator-activated receptor alpha, and interleukin 1β were upregulated whereas Sirtuin 1 and insulin receptor substrate 1 gene expression were found downregulated in dASC compared to cells obtained from healthy subjects. Taken together our data indicate that dASC lose their ability to differentiate into mature and functional adipocytes. In conclusion, our in vitro study is the first to suggest that diabetic patients might develop obesity through a hypertrophy of existing mature adipocytes due to failure turnover of adipose tissue.

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

    PubMed

    Mills, Jason C; Sansom, Owen J

    2015-07-14

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

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

    PubMed Central

    Mills, Jason C.; Sansom, Owen J.

    2016-01-01

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

  12. Obesity Determines the Immunophenotypic Profile and Functional Characteristics of Human Mesenchymal Stem Cells From Adipose Tissue

    PubMed Central

    Pachón-Peña, Gisela; Serena, Carolina; Ejarque, Miriam; Petriz, Jordi; Duran, Xevi; Oliva-Olivera, W.; Simó, Rafael; Tinahones, Francisco J.

    2016-01-01

    Adipose tissue is a major source of mesenchymal stem cells (MSCs), which possess a variety of properties that make them ideal candidates for regenerative and immunomodulatory therapies. Here, we compared the immunophenotypic profile of human adipose-derived stem cells (hASCs) from lean and obese individuals, and explored its relationship with the apparent altered plasticity of hASCs. We also hypothesized that persistent hypoxia treatment of cultured hASCs may be necessary but not sufficient to drive significant changes in mature adipocytes. hASCs were obtained from subcutaneous adipose tissue of healthy, adult, female donors undergoing abdominal plastic surgery: lean (n = 8; body mass index [BMI]: 23 ± 1 kg/m2) and obese (n = 8; BMI: 35 ± 5 kg/m2). Cell surface marker expression, proliferation and migration capacity, and adipogenic differentiation potential of cultured hASCs at two different oxygen conditions were studied. Compared with lean-derived hASCs, obese-derived hASCs demonstrated increased proliferation and migration capacity but decreased lipid droplet accumulation, correlating with a higher expression of human leukocyte antigen (HLA)-II and cluster of differentiation (CD) 106 and lower expression of CD29. Of interest, adipogenic differentiation modified CD106, CD49b, HLA-ABC surface protein expression, which was dependent on the donor’s BMI. Additionally, low oxygen tension increased proliferation and migration of lean but not obese hASCs, which correlated with an altered CD36 and CD49b immunophenotypic profile. In summary, the differences observed in proliferation, migration, and differentiation capacity in obese hASCs occurred in parallel with changes in cell surface markers, both under basal conditions and during differentiation. Therefore, obesity is an important determinant of stem cell function independent of oxygen tension. Significance The obesity-related hypoxic environment may have latent effects on human adipose tissue-derived mesenchymal

  13. Comparative gene expression profiling in human-induced pluripotent stem cell--derived cardiocytes and human and cynomolgus heart tissue.

    PubMed

    Puppala, Dinesh; Collis, Leon P; Sun, Sunny Z; Bonato, Vinicius; Chen, Xian; Anson, Blake; Pletcher, Mathew; Fermini, Bernard; Engle, Sandra J

    2013-01-01

    Cardiotoxicity is one of the leading causes of drug attrition. Current in vitro models insufficiently predict cardiotoxicity, and there is a need for alternative physiologically relevant models. Here we describe the gene expression profile of human-induced pluripotent stem cell-derived cardiocytes (iCC) postthaw over a period of 42 days in culture and compare this profile to human fetal and adult as well as adult cynomolgus nonhuman primate (NHP, Macaca fascicularis) heart tissue. Our results indicate that iCC express relevant cardiac markers such as ion channels (SCN5A, KCNJ2, CACNA1C, KCNQ1, and KCNH2), tissue-specific structural markers (MYH6, MYLPF, MYBPC3, DES, TNNT2, and TNNI3), and transcription factors (NKX2.5, GATA4, and GATA6) and lack the expression of stem cell markers (FOXD3, GBX2, NANOG, POU5F1, SOX2, and ZFP42). Furthermore, we performed a functional evaluation of contractility of the iCC and showed functional and pharmacological correlations with myocytes isolated from adult NHP hearts. These results suggest that stem cell-derived cardiocytes may represent a novel in vitro model to study human cardiac toxicity with potential ex vivo and in vivo translation.

  14. Human bone marrow and adipose tissue mesenchymal stem cells: a user's guide.

    PubMed

    Mosna, Federico; Sensebé, Luc; Krampera, Mauro

    2010-10-01

    Mesenchymal stem cells (MSCs) are adult stem cells that hold great promise in the field of regenerative medicine. They can be isolated from almost any tissue of the body and display, after expansion, very similar properties and minor differences, probably due to their microenvironment of origin. Expansion in vitro can be obtained in cytokine-free, serum-enriched media, as well as in serum-free, basic fibroblast growth factor-enriched media. A detailed immunophenotypic analysis is required to test the purity of the preparation, but no unique distinguishing marker has been described as yet. Functional assays, that is, differentiation studies in vitro, are needed to prove multilineage differentiation of expanded cells, and demonstration of pluripotency is necessary to identify most immature precursors. MSCs show powerful immunomodulative properties toward most of the cells of the immune system: this strengthens the theoretical rationale for their use also in an allogeneic setting across the major histocompatibility complex (MHC) immunological barriers. Systemic intravenous injection and local use have been tried: after systemic injection, MSCs show a high degree of chemotaxis based on pro-inflammatory cytokines, and localize at inflamed and neoplastic tissues; local regeneration has been improved using synthetic, as well as organic scaffolds. On the other hand, inadequate heterotopic in vivo differentiation and neoplastic transformation are potential risks of this form of cell therapy, even if evidence of this sort has been collected only from studies in mice, and generally after prolonged in vitro expansion. This review tries to provide a detailed technical overview of the methods used for human bone-marrow (BM)-derived and adipose-tissue (AT)-derived MSC isolation, in vitro expansion, and characterization for tissue repair. We chose to use BM-MSCs as a model to describe techniques that have been used for MSC isolation and expansion from very different sources, and

  15. Autologous tissue patch rich in stem cells created in the subcutaneous tissue

    PubMed Central

    Garcia-Gomez, Ignacio; Gudehithlu, Krishnamurthy P; Arruda, Jose A L; Singh, Ashok K

    2015-01-01

    AIM: To investigate whether we could create natural autologous tissue patches in the subcutaneous space for organ repair. METHODS: We implanted the following three types of inert foreign bodies in the subcutaneous tissue of rats to produce autologous tissue patches of different geometries: (1) a large-sized polyvinyl tube (L = 25 mm, internal diameter = 7 mm) sealed at both ends by heat application for obtaining a large flat piece of tissue patch for organ repair; (2) a fine polyvinyl tubing (L = 25 mm, internal diameter = 3 mm) for creating cylindrically shaped grafts for vascular or nerve repair; and (3) a slurry of polydextran particle gel for inducing a bladder-like tissue. Implantation of inert materials was carried out by making a small incision on one or either side of the thoracic-lumbar region of rats. Subcutaneous pockets were created by blunt dissection around the incision into which the inert bodies were inserted (1 or 2 per rat). The incisions were closed with silk sutures, and the animals were allowed to recover. In case of the polydextran gel slurry 5 mL of the slurry was injected in the subcutaneous space using an 18 gauge needle. After implanting the foreign bodies a newly regenerated encapsulating tissue developed around the foreign bodies. The tissues were harvested after 4-42 d of implantation and studied by gross examination, histology, and histochemistry for organization, vascularity, and presence of mesenchymal stem cells (MSCs) (CD271+CD34+ cells). RESULTS: Implanting a large cylindrically shaped polyvinyl tube resulted in a large flat sheet of tissue that could be tailored to a specific size and shape for use as a tissue patch for repairing large organs. Implanting a smaller sized polyvinyl tube yielded a cylindrical tissue that could be useful for repairing nerves and blood vessels. This type of patch could be obtained in different lengths by varying the length of the implanted tube. Implanting a suspension of inert polydextran suspension

  16. Catalog of gene expression in adult neural stem cells and their in vivo microenvironment

    SciTech Connect

    Williams, Cecilia; Wirta, Valtteri; Meletis, Konstantinos; Wikstroem, Lilian; Carlsson, Leif; Frisen, Jonas; Lundeberg, Joakim . E-mail: joakim.lundeberg@biotech.kth.se

    2006-06-10

    Stem cells generally reside in a stem cell microenvironment, where cues for self-renewal and differentiation are present. However, the genetic program underlying stem cell proliferation and multipotency is poorly understood. Transcriptome analysis of stem cells and their in vivo microenvironment is one way of uncovering the unique stemness properties and provides a framework for the elucidation of stem cell function. Here, we characterize the gene expression profile of the in vivo neural stem cell microenvironment in the lateral ventricle wall of adult mouse brain and of in vitro proliferating neural stem cells. We have also analyzed an Lhx2-expressing hematopoietic-stem-cell-like cell line in order to define the transcriptome of a well-characterized and pure cell population with stem cell characteristics. We report the generation, assembly and annotation of 50,792 high-quality 5'-end expressed sequence tag sequences. We further describe a shared expression of 1065 transcripts by all three stem cell libraries and a large overlap with previously published gene expression signatures for neural stem/progenitor cells and other multipotent stem cells. The sequences and cDNA clones obtained within this framework provide a comprehensive resource for the analysis of genes in adult stem cells that can accelerate future stem cell research.

  17. Stem cells and their niches: integrated units that maintain Drosophila tissues.

    PubMed

    Spradling, A C; Nystul, T; Lighthouse, D; Morris, L; Fox, D; Cox, R; Tootle, T; Frederick, R; Skora, A

    2008-01-01

    The genetic analysis of four distinct Drosophila stem cells and their niches has revealed principles of stem cell biology that are likely to apply widely. A stem cell and its niche act together as integral parts of a system that supplies replacement cells when and where they are needed within a tissue. Stem cell/niche units are highly regulated and continue to operate despite the periodic turnover and replacement of all of their component cells. To successfully respond to tissue needs, these units receive and process a wide range of local and systemic information. A stem cell alone would be no more use at this task than an isolated neuron. It is only when integrated into a system of multiple interacting cells (the niche) that stem cells achieve the capacity to serve as the fundamental units of tissue homeostasis and repair.

  18. Axonal control of the adult neural stem cell niche.

    PubMed

    Tong, Cheuk Ka; Chen, Jiadong; Cebrián-Silla, Arantxa; Mirzadeh, Zaman; Obernier, Kirsten; Guinto, Cristina D; Tecott, Laurence H; García-Verdugo, Jose Manuel; Kriegstein, Arnold; Alvarez-Buylla, Arturo

    2014-04-03

    The ventricular-subventricular zone (V-SVZ) is an extensive germinal niche containing neural stem cells (NSCs) in the walls of the lateral ventricles of the adult brain. How the adult brain's neural activity influences the behavior of adult NSCs remains largely unknown. We show that serotonergic (5HT) axons originating from a small group of neurons in the raphe form an extensive plexus on most of the ventricular walls. Electron microscopy revealed intimate contacts between 5HT axons and NSCs (B1) or ependymal cells (E1) and these cells were labeled by a transsynaptic viral tracer injected into the raphe. B1 cells express the 5HT receptors 2C and 5A. Electrophysiology showed that activation of these receptors in B1 cells induced small inward currents. Intraventricular infusion of 5HT2C agonist or antagonist increased or decreased V-SVZ proliferation, respectively. These results indicate that supraependymal 5HT axons directly interact with NSCs to regulate neurogenesis via 5HT2C.

  19. Live Imaging of Adult Neural Stem Cells in Rodents

    PubMed Central

    Ortega, Felipe; Costa, Marcos R.

    2016-01-01

    The generation of cells of the neural lineage within the brain is not restricted to early development. New neurons, oligodendrocytes, and astrocytes are produced in the adult brain throughout the entire murine life. However, despite the extensive research performed in the field of adult neurogenesis during the past years, fundamental questions regarding the cell biology of adult neural stem cells (aNSCs) remain to be uncovered. For instance, it is crucial to elucidate whether a single aNSC is capable of differentiating into all three different macroglial cell types in vivo or these distinct progenies constitute entirely separate lineages. Similarly, the cell cycle length, the time and mode of division (symmetric vs. asymmetric) that these cells undergo within their lineage progression are interesting questions under current investigation. In this sense, live imaging constitutes a valuable ally in the search of reliable answers to the previous questions. In spite of the current limitations of technology new approaches are being developed and outstanding amount of knowledge is being piled up providing interesting insights in the behavior of aNSCs. Here, we will review the state of the art of live imaging as well as the alternative models that currently offer new answers to critical questions. PMID:27013941

  20. Axonal Control of the Adult Neural Stem Cell Niche

    PubMed Central

    Tong, Cheuk Ka; Chen, Jiadong; Cebrián-Silla, Arantxa; Mirzadeh, Zaman; Obernier, Kirsten; Guinto, Cristina D.; Tecott, Laurence H.; García-Verdugo, Jose Manuel; Kriegstein, Arnold; Alvarez-Buylla, Arturo

    2014-01-01

    SUMMARY The ventricular-subventricular zone (V-SVZ) is an extensive germinal niche containing neural stem cells (NSC) in the walls of the lateral ventricles of the adult brain. How the adult brain’s neural activity influences the behavior of adult NSCs remains largely unknown. We show that serotonergic (5HT) axons originating from a small group of neurons in the raphe form an extensive plexus on most of the ventricular walls. Electron microscopy revealed intimate contacts between 5HT axons and NSCs (B1) or ependymal cells (E1) and these cells were labeled by a transsynaptic viral tracer injected into the raphe. B1 cells express the 5HT receptors 2C and 5A. Electrophysiology showed that activation of these receptors in B1 cells induced small inward currents. Intraventricular infusion of 5HT2C agonist or antagonist increased or decreased V-SVZ proliferation, respectively. These results indicate that supraependymal 5HT axons directly interact with NSCs to regulate neurogenesis via 5HT2C. PMID:24561083

  1. Tissue adaptations to gravitational stress - Newborn versus adult giraffes

    NASA Technical Reports Server (NTRS)

    Hargens, Alan R; Gershuni, David H.; Danzig, Larry A.; Millard, Ronald W.; Pettersson, Knut

    1988-01-01

    Preliminary results on developmental alterations in load-bearing tissues of newborn and adult giraffes are presented. Attention is focused on vascular wall thickness in relation to local blood pressure, and on meniscal adaptations to increased load bearing in the developing giraffe. It is believed that the developing giraffe provides an excellent model for investigations of adaptive mechanisms of increased weight bearing.

  2. Visualization of adult stem cells within their niches using the Drosophila germline as a model system.

    PubMed

    König, Annekatrin; Shcherbata, Halyna R

    2013-01-01

    The germaria of the fruit fly Drosophila melanogaster present an excellent model to study germline stem cell-niche interactions. Two to three adult stem cells are surrounded by a number of somatic cells that form the niche. Here we describe how Drosophilae germaria can be dissected and specifically immuno-stained to allow for identification and analysis of both the adult stem cells and their somatic niche cells.

  3. Therapeutic Strategies for Oxidative Stress-Related Cardiovascular Diseases: Removal of Excess Reactive Oxygen Species in Adult Stem Cells.

    PubMed

    Kim, Hyunyun; Yun, Jisoo; Kwon, Sang-Mo

    Accumulating evidence indicates that acute and chronic uncontrolled overproduction of oxidative stress-related factors including reactive oxygen species (ROS) causes cardiovascular diseases (CVDs), atherosclerosis, and diabetes. Moreover ROS mediate various signaling pathways underlying vascular inflammation in ischemic tissues. With respect to stem cell-based therapy, several studies clearly indicate that modulating antioxidant production at cellular levels enhances stem/progenitor cell functionalities, including proliferation, long-term survival in ischemic tissues, and complete differentiation of transplanted cells into mature vascular cells. Recently emerging therapeutic strategies involving adult stem cells, including endothelial progenitor cells (EPCs), for treating ischemic CVDs have highlighted the need to control intracellular ROS production, because it critically affects the replicative senescence of ex vivo expanded therapeutic cells. Better understanding of the complexity of cellular ROS in stem cell biology might improve cell survival in ischemic tissues and enhance the regenerative potentials of transplanted stem/progenitor cells. In this review, we will discuss the nature and sources of ROS, drug-based therapeutic strategies for scavenging ROS, and EPC based therapeutic strategies for treating oxidative stress-related CVDs. Furthermore, we will discuss whether primed EPCs pretreated with natural ROS-scavenging compounds are crucial and promising therapeutic strategies for vascular repair.

  4. Therapeutic Strategies for Oxidative Stress-Related Cardiovascular Diseases: Removal of Excess Reactive Oxygen Species in Adult Stem Cells

    PubMed Central

    Yun, Jisoo

    2016-01-01

    Accumulating evidence indicates that acute and chronic uncontrolled overproduction of oxidative stress-related factors including reactive oxygen species (ROS) causes cardiovascular diseases (CVDs), atherosclerosis, and diabetes. Moreover ROS mediate various signaling pathways underlying vascular inflammation in ischemic tissues. With respect to stem cell-based therapy, several studies clearly indicate that modulating antioxidant production at cellular levels enhances stem/progenitor cell functionalities, including proliferation, long-term survival in ischemic tissues, and complete differentiation of transplanted cells into mature vascular cells. Recently emerging therapeutic strategies involving adult stem cells, including endothelial progenitor cells (EPCs), for treating ischemic CVDs have highlighted the need to control intracellular ROS production, because it critically affects the replicative senescence of ex vivo expanded therapeutic cells. Better understanding of the complexity of cellular ROS in stem cell biology might improve cell survival in ischemic tissues and enhance the regenerative potentials of transplanted stem/progenitor cells. In this review, we will discuss the nature and sources of ROS, drug-based therapeutic strategies for scavenging ROS, and EPC based therapeutic strategies for treating oxidative stress-related CVDs. Furthermore, we will discuss whether primed EPCs pretreated with natural ROS-scavenging compounds are crucial and promising therapeutic strategies for vascular repair. PMID:27668035

  5. The next generation of burns treatment: intelligent films and matrix, controlled enzymatic debridement, and adult stem cells.

    PubMed

    Drago, H; Marín, G H; Sturla, F; Roque, G; Mártire, K; Díaz Aquino, V; Lamonega, R; Gardiner, C; Ichim, T; Riordan, N; Raimondi, J C; Bossi, S; Samadikuchaksaraei, A; van Leeuwen, M; Tau, J M; Núñez, L; Larsen, G; Spretz, R; Mansilla, E

    2010-01-01

    We describe a novel technology based on nanoengineered multifunctional acellular biologic scaffolds combined with wound dressings and films of the same kind. This method allows selective delivery and release of shielded biomaterials and bioactive substances to a desired wound or damaged tissue while stimulating the selective anchoring and adhesion of endogenous circulating repairing cells, such as mesenchymal stem cells, to obtain a faster and more physiologic healing process. We also present a new controlled enzymatic debridement process for more effective burned tissue scarolysis. In light of our preliminary in vitro and in vivo data, we are convinced that these approaches can include the use of other kinds of adult stem cells, such as endometrial regenerative cells, to improve the vascularization of the constructs, with great potential in the entire tissue and organ regeneration field but especially for the treatment of severely burned patients, changing the way these lesions may be treated in the future.

  6. Microenvironmental determinants of adult neural stem cell proliferation and lineage commitment in the healthy and injured central nervous system.

    PubMed

    Moyse, Emmanuel; Segura, Stéphanie; Liard, Oliver; Mahaut, Stéphanie; Mechawar, Naguib

    2008-09-01

    The discovery of neural stem cells (NSC) which ensure continuous neurogenesis in the adult mammalian brain, has led to a conceptual revolution in basic neuroscience and to high hopes for clinical nervous tissue repair. However, several research issues remain to address before neural stem cells can be harnessed for regenerative therapies. The presence of NSC in a nervous structure is demonstrated in vitro by primary culture of dissociated adult nervous tissue in the presence of the specific mitogens EGF and bFGF. This leads to spherical masses of proliferating cells endowed with capacities for self-renewal and, after growth factor removal, differentiation into the three characteristic cell types of nervous tissue (neurons, astrocytes, oligodendrocytes). In vivo, neurogenesis per se, i.e. production of new neurons, occurs only in a small subset of NSC-endowed structures. The production of oligodendrocytes, i.e. myelinating glial cells, is similarly restricted. Such in vivo restrictions were formally demonstrated to arise from the tissular microenvironnement, which led to the emerging concept of "neurogenic niche". In this context, major challenges now consist in identifying the nature of tissue-specific extracellular signals that determine lineage commitment of NSC progeny, understanding why NSCs display weak in vivo reactivity to lesions compared to other stem cell types in adults, and identifying the factors behind the very high resistance to tumorigenesis displayed by NSCs. Altogether, the current data offer hope for the future use of adult NSCs in regenerative therapies, provided that tissue-specific signals are identified in view of counteracting the intrinsic repression of new cell genesis and/or stimulating endogenous NSC recruitment to lesion sites.

  7. Effect of Cell Origin and Timing of Delivery for Stem Cell-Based Bone Tissue Engineering Using Biologically Functionalized Hydrogels

    PubMed Central

    Dosier, Christopher R.; Uhrig, Brent A.; Willett, Nick J.; Krishnan, Laxminarayanan; Li, Mon-Tzu Alice; Stevens, Hazel Y.; Schwartz, Zvi; Boyan, Barbara D.

    2015-01-01

    Despite progress in bone tissue engineering, the healing of critically sized diaphyseal defects remains a clinical challenge. A stem cell-based approach is an attractive alternative to current treatment techniques. The objective of this study was to examine the ability of adult stem cells to enhance bone formation when co-delivered with the osteoinductive factor bone morphogenetic protein-2 (BMP-2) in a biologically functionalized hydrogel. First, adipose and bone marrow-derived mesenchymal stem cells (ADSCs and BMMSCs) were screened for their potential to form bone when delivered in an RGD functionalized alginate hydrogel using a subcutaneous implant model. BMMSCs co-delivered with BMP-2 produced significantly more mineralized tissue compared with either ADSCs co-delivered with BMP-2 or acellular hydrogels containing BMP-2. Next, the ability of BMMSCs to heal a critically sized diaphyseal defect with a nonhealing dose of BMP-2 was tested using the alginate hydrogel as an injectable cell carrier. The effect of timing of therapeutic delivery on bone regeneration was also tested in the diaphyseal model. A 7 day delayed injection of the hydrogel into the defect site resulted in less mineralized tissue formation than immediate delivery of the hydrogel. By 12 weeks, BMMSC-loaded hydrogels produced significantly more bone than acellular constructs regardless of immediate or delayed treatment. For immediate delivery, bridging of defects treated with BMMSC-loaded hydrogels occurred at a rate of 75% compared with a 33% bridging rate for acellular-treated defects. No bridging was observed in any of the delayed delivery samples for any of the groups. Therefore, for this cell-based bone tissue engineering approach, immediate delivery of constructs leads to an overall enhanced healing response compared with delayed delivery techniques. Further, these studies demonstrate that co-delivery of adult stem cells, specifically BMMSCs, with BMP-2 enhances bone regeneration in a

  8. Oct-4 expression in adult human differentiated cells challenges its role as a pure stem cell marker.

    PubMed

    Zangrossi, Stefano; Marabese, Mirko; Broggini, Massimo; Giordano, Rosaria; D'Erasmo, Marco; Montelatici, Elisa; Intini, Daniela; Neri, Antonino; Pesce, Maurizio; Rebulla, Paolo; Lazzari, Lorenza

    2007-07-01

    The Oct-4 transcription factor, a member of the POU family that is also known as Oct-3 and Oct3/4, is expressed in totipotent embryonic stem cells (ES) and germ cells, and it has a unique role in development and in the determination of pluripotency. ES may have their postnatal counterpart in the adult stem cells, recently described in various mammalian tissues, and Oct-4 expression in putative stem cells purified from adult tissues has been considered a real marker of stemness. In this context, normal mature adult cells would not be expected to show Oct-4 expression. On the contrary, we demonstrated, using reverse transcription-polymerase chain reaction (PCR) (total RNA, Poly A+), real-time PCR, immunoprecipitation, Western blotting, band shift, and immunofluorescence, that human peripheral blood mononuclear cells, genetically stable and mainly terminally differentiated cells with well defined functions and a limited lifespan, express Oct-4. These observations raise the question as to whether the role of Oct-4 as a marker of pluripotency should be challenged. Our findings suggest that the presence of Oct-4 is not sufficient to define a cell as pluripotent, and that additional measures should be used to avoid misleading results in the case of an embryonic-specific gene with a large number of pseudogenes that may contribute to false identification of Oct-4 in adult stem cells. These unexpected findings may provide new insights into the role of Oct-4 in fully differentiated cells. Disclosure of potential conflicts of interest is found at the end of this article.

  9. Development of Synthetic and Natural Materials for Tissue Engineering Applications Using Adipose Stem Cells

    PubMed Central

    He, Yunfan; Lu, Feng

    2016-01-01

    Adipose stem cells have prominent implications in tissue regeneration due to their abundance and relative ease of harvest from adipose tissue and their abilities to differentiate into mature cells of various tissue lineages and secrete various growth cytokines. Development of tissue engineering techniques in combination with various carrier scaffolds and adipose stem cells offers great potential in overcoming the existing limitations constraining classical approaches used in plastic and reconstructive surgery. However, as most tissue engineering techniques are new and highly experimental, there are still many practical challenges that must be overcome before laboratory research can lead to large-scale clinical applications. Tissue engineering is currently a growing field of medical research; in this review, we will discuss the progress in research on biomaterials and scaffolds for tissue engineering applications using adipose stem cells. PMID:26977158

  10. Cardiomyocyte clusters derived from human embryonic stem cells share similarities with human heart tissue.

    PubMed

    Asp, Julia; Steel, Daniella; Jonsson, Marianne; Améen, Caroline; Dahlenborg, Kerstin; Jeppsson, Anders; Lindahl, Anders; Sartipy, Peter

    2010-10-01

    Cardiotoxicity testing is a key activity in the pharmaceutical industry in order to detect detrimental effects of new drugs. A reliable human in vitro model would both be beneficial in selection of lead compounds and be important for reducing animal experimentation. However, the human heart is a complex organ composed of many distinct types of cardiomyocytes, but cardiomyocyte clusters (CMCs) derived from human embryonic stem cells could be an option for a cellular model. Data on functional properties of CMCs demonstrate similarities to their in vivo analogues in human. However, development of an in vitro model requires a more thorough comparison of CMCs to human heart tissue. Therefore, we directly compared individually isolated CMCs to human fetal, neonatal, adult atrial and ventricular heart tissues. Real-time qPCR analysis of mRNA levels and protein staining of ion channels and cardiac markers showed in general a similar expression pattern in CMCs and human heart. Moreover, a significant decrease in beat frequency was noted after addition of Zatebradine, a blocker to I(f) involved in regulation of spontaneous contraction in CMCs. The results underscore the similarities of CMCs to human cardiac tissue, and further support establishment of novel cardiotoxicity assays based on the CMCs in drug discovery.

  11. Advances in tissue engineering through stem cell-based co-culture.

    PubMed

    Paschos, Nikolaos K; Brown, Wendy E; Eswaramoorthy, Rajalakshmanan; Hu, Jerry C; Athanasiou, Kyriacos A

    2015-05-01

    Stem cells are the future in tissue engineering and regeneration. In a co-culture, stem cells not only provide a target cell source with multipotent differentiation capacity, but can also act as assisting cells that promote tissue homeostasis, metabolism, growth and repair. Their incorporation into co-culture systems seems to be important in the creation of complex tissues or organs. In this review, critical aspects of stem cell use in co-culture systems are discussed. Direct and indirect co-culture methodologies used in tissue engineering are described, along with various characteristics of cellular interactions in these systems. Direct cell-cell contact, cell-extracellular matrix interaction and signalling via soluble factors are presented. The advantages of stem cell co-culture strategies and their applications in tissue engineering and regenerative medicine are portrayed through specific examples for several tissues, including orthopaedic soft tissues, bone, heart, vasculature, lung, kidney, liver and nerve. A concise review of the progress and the lessons learned are provided, with a focus on recent developments and their implications. It is hoped that knowledge developed from one tissue can be translated to other tissues. Finally, we address challenges in tissue engineering and regenerative medicine that can potentially be overcome via employing strategies for stem cell co-culture use.

  12. Potential application of extracellular vesicles of human adipose tissue-derived mesenchymal stem cells in Alzheimer's disease therapeutics.

    PubMed

    Katsuda, Takeshi; Oki, Katsuyuki; Ochiya, Takahiro

    2015-01-01

    In the last 20 years, extracellular vesicles (EVs) have attracted attention as a versatile cell-cell communication mediator. The biological significance of EVs remains to be fully elucidated, but many reports have suggested that the functions of EVs mirror, at least in part, those of the cells from which they originate. Mesenchymal stem cells (MSCs) are a type of adult stem cell that can be isolated from connective tissue including bone marrow and adipose tissue and have emerged as an attractive candidate for cell therapy applications. Accordingly, an increasing number of reports have shown that EVs derived from MSCs have therapeutic potential in multiple diseases. We recently reported a novel therapeutic potential of EVs secreted from human adipose tissue-derived MSCs (hADSCs) (also known as adipose tissue-derived stem cells; ASCs) against Alzheimer's disease (AD). We found that hADSCs secrete exosomes carrying enzymatically active neprilysin, the most important β-amyloid peptide (Aβ)-degrading enzyme in the brain. In this chapter, we describe a method by which to evaluate the therapeutic potential of hADSC-derived EVs against AD from the point of view of their Aβ-degrading capacity.

  13. Electric fish: new insights into conserved processes of adult tissue regeneration.

    PubMed

    Unguez, Graciela A

    2013-07-01

    Biology is replete with examples of regeneration, the process that allows animals to replace or repair cells, tissues and organs. As on land, vertebrates in aquatic environments experience the occurrence of injury with varying frequency and to different degrees. Studies demonstrate that ray-finned fishes possess a very high capacity to regenerate different tissues and organs when they are adults. Among fishes that exhibit robust regenerative capacities are the neotropical electric fishes of South America (Teleostei: Gymnotiformes). Specifically, adult gymnotiform electric fishes can regenerate injured brain and spinal cord tissues and restore amputated body parts repeatedly. We have begun to identify some aspects of the cellular and molecular mechanisms of tail regeneration in the weakly electric fish Sternopygus macrurus (long-tailed knifefish) with a focus on regeneration of skeletal muscle and the muscle-derived electric organ. Application of in vivo microinjection techniques and generation of myogenic stem cell markers are beginning to overcome some of the challenges owing to the limitations of working with non-genetic animal models with extensive regenerative capacity. This review highlights some aspects of tail regeneration in S. macrurus and discusses the advantages of using gymnotiform electric fishes to investigate the cellular and molecular mechanisms that produce new cells during regeneration in adult vertebrates.

  14. Electric fish: new insights into conserved processes of adult tissue regeneration

    PubMed Central

    Unguez, Graciela A.

    2013-01-01

    Summary Biology is replete with examples of regeneration, the process that allows animals to replace or repair cells, tissues and organs. As on land, vertebrates in aquatic environments experience the occurrence of injury with varying frequency and to different degrees. Studies demonstrate that ray-finned fishes possess a very high capacity to regenerate different tissues and organs when they are adults. Among fishes that exhibit robust regenerative capacities are the neotropical electric fishes of South America (Teleostei: Gymnotiformes). Specifically, adult gymnotiform electric fishes can regenerate injured brain and spinal cord tissues and restore amputated body parts repeatedly. We have begun to identify some aspects of the cellular and molecular mechanisms of tail regeneration in the weakly electric fish Sternopygus macrurus (long-tailed knifefish) with a focus on regeneration of skeletal muscle and the muscle-derived electric organ. Application of in vivo microinjection techniques and generation of myogenic stem cell markers are beginning to overcome some of the challenges owing to the limitations of working with non-genetic animal models with extensive regenerative capacity. This review highlights some aspects of tail regeneration in S. macrurus and discusses the advantages of using gymnotiform electric fishes to investigate the cellular and molecular mechanisms that produce new cells during regeneration in adult vertebrates. PMID:23761473

  15. The Influence of Modified Silica Nanomaterials on Adult Stem Cell Culture

    PubMed Central

    Tarpani, Luigi; Morena, Francesco; Gambucci, Marta; Zampini, Giulia; Massaro, Giuseppina; Argentati, Chiara; Emiliani, Carla; Martino, Sabata; Latterini, Loredana

    2016-01-01

    The preparation of tailored nanomaterials able to support cell growth and viability is mandatory for tissue engineering applications. In the present work, silica nanoparticles were prepared by a sol-gel procedure and were then functionalized by condensation of amino groups and by adsorption of silver nanoparticles. Transmission electron microscopy (TEM) imaging was used to establish the morphology and the average dimensions of about 130 nm, which were not affected by the functionalization. The three silica samples were deposited (1 mg/mL) on cover glasses, which were used as a substrate to culture adult human bone marrow-mesenchymal stem cells (hBM-MSCs) and human adipose-derived stem cells (hASCs). The good cell viability over the different silica surfaces was evaluated by monitoring the mitochondrial dehydrogenase activity. The analysis of the morphological parameters (aspect ratio, cell length, and nuclear shape Index) yielded information about the interactions of stem cells with the surface of three different nanoparticles. The data are discussed in terms of chemical properties of the surface of silica nanoparticles.

  16. Asymptomatic and isolated accessory mitral valve tissue in an adult.

    PubMed

    Hisatomi, Kazuki; Hashizume, Koji; Tanigawa, Kazuyoshi; Miura, Takashi; Matsukuma, Seiji; Yokose, Shogo; Sumi, Mizuki; Eishi, Kiyoyuki

    2016-02-01

    Accessory mitral valve (AMV) tissue is a congenital anomaly that occurs in association with other congenital anomalies, and is an uncommon cause of left ventricular outflow tract obstruction. It is usually detected in early childhood when accompanied by symptoms of obstruction of the left ventricular outflow tract, and is rarely diagnosed in adults. We present a case of a 53-year-old man who was referred to our institution for evaluation of a systolic heart murmur. Echocardiography disclosed a diagnosis of AMV tissue. This case was uncommon because of the lack of severe obstruction of left ventricular outflow, cardiac symptoms, or other cardiac anomalies. We were able to carry out surgical resection of AMV tissue to avert possible progression of aortic insufficiency and the risk of a cerebrovascular embolization. The patient's postoperative course was uneventful, and postoperative echocardiography showed no residual accessory mitral tissue.

  17. Genetic inactivation of Cdk7 leads to cell cycle arrest and induces premature aging due to adult stem cell exhaustion

    PubMed Central

    Ganuza, Miguel; Sáiz-Ladera, Cristina; Cañamero, Marta; Gómez, Gonzalo; Schneider, Ralph; Blasco, María A; Pisano, David; Paramio, Jesús M; Santamaría, David; Barbacid, Mariano

    2012-01-01

    Cyclin-dependent kinase (Cdk)7, the catalytic subunit of the Cdk-activating kinase (CAK) complex has been implicated in the control of cell cycle progression and of RNA polymerase II (RNA pol II)-mediated transcription. Genetic inactivation of the Cdk7 locus revealed that whereas Cdk7 is completely dispensable for global transcription, is essential for the cell cycle via phosphorylation of Cdk1 and Cdk2. In vivo, Cdk7 is also indispensable for cell proliferation except during the initial stages of embryonic development. Interestingly, widespread elimination of Cdk7 in adult tissues with low proliferative indexes had no phenotypic consequences. However, ablation of conditional Cdk7 alleles in tissues with elevated cellular turnover led to the efficient repopulation of these tissues with Cdk7-expressing cells most likely derived from adult stem cells that may have escaped the inactivation of their targeted Cdk7 alleles. This process, a physiological attempt to maintain tissue homeostasis, led to the attrition of adult stem cell pools and to the appearance of age-related phenotypes, including telomere shortening and early death. PMID:22505032

  18. Regulation of seminiferous tubule-associated stem Leydig cells in adult rat testes.

    PubMed

    Li, Xiaoheng; Wang, Zhao; Jiang, Zhenming; Guo, Jingjing; Zhang, Yuxi; Li, Chenhao; Chung, Jinyong; Folmer, Janet; Liu, June; Lian, Qingquan; Ge, Renshan; Zirkin, Barry R; Chen, Haolin

    2016-03-08

    Testicular Leydig cells are the primary source of testosterone in males. Adult Leydig cells have been shown to arise from stem cells present in the neonatal testis. Once established, adult Leydig cells turn over only slowly during adult life, but when these cells are eliminated experimentally from the adult testis, new Leydig cells rapidly reappear. As in the neonatal testis, stem cells in the adult testis are presumed to be the source of the new Leydig cells. As yet, the mechanisms involved in regulating the proliferation and differentiation of these stem cells remain unknown. We developed a unique in vitro system of cultured seminiferous tubules to assess the ability of factors from the seminiferous tubules to regulate the proliferation of the tubule-associated stem cells, and their subsequent entry into the Leydig cell lineage. The proliferation of the stem Leydig cells was stimulated by paracrine factors including Desert hedgehog (DHH), basic fibroblast growth factor (FGF2), platelet-derived growth factor (PDGF), and activin. Suppression of proliferation occurred with transforming growth factor β (TGF-β). The differentiation of the stem cells was regulated positively by DHH, lithium- induced signaling, and activin, and negatively by TGF-β, PDGFBB, and FGF2. DHH functioned as a commitment factor, inducing the transition of stem cells to the progenitor stage and thus into the Leydig cell lineage. Additionally, CD90 (Thy1) was found to be a unique stem cell surface marker that was used to obtain purified stem cells by flow cytometry.

  19. β-Cell neogenesis: experimental considerations in adult stem cell differentiation.

    PubMed

    Iskovich, Svetlana; Goldenberg-Cohen, Nitza; Stein, Jerry; Yaniv, Isaac; Farkas, Daniel L; Askenasy, Nadir

    2011-04-01

    The contribution of stem cells derived from adult tissues to the recovery of pancreatic islets from chemical injury is controversial. Analysis of nonhematopoietic differentiation of bone marrow-derived cells has yielded positive and negative results under different experimental conditions. Using the smallest subset of bone marrow cells lacking immuno-hematopoietic lineage markers, we have detected incorporation and conversion into insulin-producing cells. Donor cells identified by genomic markers silence green fluorescent protein (GFP) expression as a feature of differentiation, in parallel to expressing PDX-1 and proinsulin. Here we elaborate potential experimental difficulties that might result in false-negative results. The use of GFP as a reporter protein is suboptimal for differentiation experiments: (a) the bone marrow of GFP donors partially expresses the reporter protein, (b) differentiating bone marrow cells silence GFP expression, and (c) the endocrine pancreas is constitutively negative for GFP. In addition, design of the experiments, data analysis, and interpretation encounter numerous objective and subjective difficulties. Rigorous evaluation under optimized experimental conditions confirms the capacity of adult bone marrow-derived stem cells to adopt endocrine developmental traits, and demonstrates that GFP downregulation and silencing is a feature of differentiation.

  20. A Comparison of Culture Characteristics between Human Amniotic Mesenchymal Stem Cells and Dental Stem Cells.

    PubMed

    Yusoff, Nurul Hidayat; Alshehadat, Saaid Ayesh; Azlina, Ahmad; Kannan, Thirumulu Ponnuraj; Hamid, Suzina Sheikh Abdul

    2015-04-01

    In the past decade, the field of stem cell biology is of major interest among researchers due to its broad therapeutic potential. Stem cells are a class of undifferentiated cells that are able to differentiate into specialised cell types. Stem cells can be classified into two main types: adult stem cells (adult tissues) and embryonic stem cells (embryos formed during the blastocyst phase of embryological development). This review will discuss two types of adult mesenchymal stem cells, dental stem cells and amniotic stem cells, with respect to their differentiation lineages, passage numbers and animal model studies. Amniotic stem cells have a greater number of differentiation lineages than dental stem cells. On the contrary, dental stem cells showed the highest number of passages compared to amniotic stem cells. For tissue regeneration based on animal studies, amniotic stem cells showed the shortest time to regenerate in comparison with dental stem cells.

  1. Genetic regulators of a pluripotent adult stem cell system in planarians identified by RNAi and clonal analysis.

    PubMed

    Wagner, Daniel E; Ho, Jaclyn J; Reddien, Peter W

    2012-03-02

    Pluripotency is a central, well-studied feature of embryonic development, but the role of pluripotent cell regulation in somatic tissue regeneration remains poorly understood. In planarians, regeneration of entire animals from tissue fragments is promoted by the activity of adult pluripotent stem cells (cNeoblasts). We utilized transcriptional profiling to identify planarian genes expressed in adult proliferating, regenerative cells (neoblasts). We also developed quantitative clonal analysis methods for expansion and differentiation of cNeoblast descendants that, together with RNAi, revealed gene roles in stem cell biology. Genes encoding two zinc finger proteins, Vasa, a LIM domain protein, Sox and Jun-like transcription factors, two candidate RNA-binding proteins, a Setd8-like protein, and PRC2 (Polycomb) were required for proliferative expansion and/or differentiation of cNeoblast-derived clones. These findings suggest that planarian stem cells utilize molecular mechanisms found in germ cells and other pluripotent cell types and identify genetic regulators of the planarian stem cell system.

  2. Multipotent (adult) and pluripotent stem cells for heart regeneration: what are the pros and cons?

    PubMed

    Liao, Song-Yan; Tse, Hung-Fat

    2013-12-24

    Heart failure after myocardial infarction is the leading cause of mortality and morbidity worldwide. Existing medical and interventional therapies can only reduce the loss of cardiomyocytes during myocardial infarction but are unable to replenish the permanent loss of cardiomyocytes after the insult, which contributes to progressive pathological left ventricular remodeling and progressive heart failure. As a result, cell-based therapies using multipotent (adult) stem cells and pluripotent stem cells (embryonic stem cells or induced pluripotent stem cells) have been explored as potential therapeutic approaches to restore cardiac function in heart failure. Nevertheless, the optimal cell type with the best therapeutic efficacy and safety for heart regeneration is still unknown. In this review, the potential pros and cons of different types of multipotent (adult) stem cells and pluripotent stem cells that have been investigated in preclinical and clinical studies are reviewed, and the future perspective of stem cell-based therapy for heart regeneration is discussed.

  3. Immunomodulatory properties of human adult and fetal multipotent mesenchymal stem cells.

    PubMed

    Chen, Pei-Min; Yen, Men-Luh; Liu, Ko-Jiunn; Sytwu, Huey-Kang; Yen, B-Linju

    2011-07-18

    In recent years, a large number of studies have contributed to our understanding of the immunomodulatory mechanisms used by multipotent mesenchymal stem cells (MSCs). Initially isolated from the bone marrow (BM), MSCs have been found in many tissues but the strong immunomodulatory properties are best studied in BM MSCs. The immunomodulatory effects of BM MSCs are wide, extending to T lymphocytes and dendritic cells, and are therapeutically useful for treatment of immune-related diseases including graft-versus-host disease as well as possibly autoimmune diseases. However, BM MSCs are very rare cells and require an invasive procedure for procurement. Recently, MSCs have also been found in fetal-stage embryo-proper and extra-embryonic tissues, and these human fetal MSCs (F-MSCs) have a higher proliferative profile, and are capable of multilineage differentiation as well as exert strong immunomodulatory effects. As such, these F-MSCs can be viewed as alternative sources of MSCs. We review here the current understanding of the mechanisms behind the immunomodulatory properties of BM MSCs and F-MSCs. An increase in our understanding of MSC suppressor mechanisms will offer insights for prevalent clinical use of these versatile adult stem cells in the near future.

  4. Adipose-Derived Stem Cells for Tissue Engineering and Regenerative Medicine Applications

    PubMed Central

    Dai, Ru; Wang, Zongjie; Samanipour, Roya; Koo, Kyo-in; Kim, Keekyoung

    2016-01-01

    Adipose-derived stem cells (ASCs) are a mesenchymal stem cell source with properties of self-renewal and multipotential differentiation. Compared to bone marrow-derived stem cells (BMSCs), ASCs can be derived from more sources and are harvested more easily. Three-dimensional (3D) tissue engineering scaffolds are better able to mimic the in vivo cellular microenvironment, which benefits the localization, attachment, proliferation, and differentiation of ASCs. Therefore, tissue-engineered ASCs are recognized as an attractive substitute for tissue and organ transplantation. In this paper, we review the characteristics of ASCs, as well as the biomaterials and tissue engineering methods used to proliferate and differentiate ASCs in a 3D environment. Clinical applications of tissue-engineered ASCs are also discussed to reveal the potential and feasibility of using tissue-engineered ASCs in regenerative medicine. PMID:27057174

  5. Direct Activation of Amidohydrolase Domain-Containing 1 Gene by Thyroid Hormone Implicates a Role in the Formation of Adult Intestinal Stem Cells During Xenopus Metamorphosis.

    PubMed

    Okada, Morihiro; Miller, Thomas C; Fu, Liezhen; Shi, Yun-Bo

    2015-09-01

    The T3-dependent anuran metamorphosis resembles postembryonic development in mammals, the period around birth when plasma T3 levels peak. In particular, the remodeling of the intestine during metamorphosis mimics neonatal intestinal maturation in mammals when the adult intestinal epithelial self-renewing system is established. We have been using intestinal metamorphosis to investigate how the organ-specific adult stem cells are formed during vertebrate development. Early studies in Xenopus laevis have shown that this process involves complete degeneration of the larval epithelium and de novo formation of adult stem cells. A tissue-specific microarray analysis of intestinal gene expression during Xenopus laevis metamorphosis has identified a number of candidate stem cell genes. Here we have carried out detailed analyses of one such gene, amidohydrolase domain containing 1 (AMDHD1) gene, which encodes an enzyme in the histidine catabolic pathway. We show that AMDHD1 is exclusively expressed in the proliferating adult epithelial stem cells during metamorphosis with little expression in other intestinal tissues. We further provide evidence that T3 activates AMDHD1 gene expression directly at the transcription level through T3 receptor binding to the AMDHD1 gene in the intestine. In addition, we have reported earlier that histidine ammonia-lyase gene, another gene in histidine catabolic pathway, is similarly regulated by T3 in the intestine. These results together suggest that histidine catabolism plays a critical role in the formation and/or proliferation of adult intestinal stem cells during metamorphosis.

  6. KCTD11 expression in medulloblastoma is lower than in adult cerebellum and higher than in neural stem cells.

    PubMed

    Zawlik, Izabela; Zakrzewska, Magdalena; Witusik, Monika; Golanska, Ewa; Kulczycka-Wojdala, Dominika; Szybka, Malgorzata; Piaskowski, Sylwester; Wozniak, Krystyna; Zakrzewski, Krzysztof; Papierz, Wielislaw; Liberski, Pawel P; Rieske, Piotr

    2006-10-01

    Medulloblastoma (MB) is the most common malignant brain tumor of childhood, and the most frequent associated genetic alteration is loss of heterozygosity on chromosome region 7p13. Two genes mapping to this region, KCTD11 (alias REN) and HIC1, have been proposed as involved in MB pathogenesis. We used real-time polymerase chain reaction in 20 tissue samples of primary MB to examine the transcriptional level of the two genes, with reference to two types of controls: adult cerebellum and fetal neural stem cells. A significant reduction of KCTD11 expression relative to adult normal cerebellum was detected in 14 of 20 (70%) of MB samples. Neural stem cells had even lower levels of KCTD11 expression than did MB. HIC1 gene expression was low ( approximately 100 times lower than KCTD11 expression) in MB, and low also in both adult cerebellum and neural stem cells. Hypermethylation of the 5'UTR or the central region of HIC1 (or both) was detected in a significant number of MB samples, as well as in cerebellum and neural stem cells. Our data suggest that KCTD11 may play an important role in MB tumorigenesis, but do not support the role of HIC1 in this tumor development. We argue that recognition of the gene or genes important in MB tumorigenesis depends in part on defining an appropriate control.

  7. Intrastriatal transplantation of adult human neural crest-derived stem cells improves functional outcome in parkinsonian rats.

    PubMed

    Müller, Janine; Ossig, Christiana; Greiner, Johannes F W; Hauser, Stefan; Fauser, Mareike; Widera, Darius; Kaltschmidt, Christian; Storch, Alexander; Kaltschmidt, Barbara

    2015-01-01

    Parkinson's disease (PD) is considered the second most frequent and one of the most severe neurodegenerative diseases, with dysfunctions of the motor system and with nonmotor symptoms such as depression and dementia. Compensation for the progressive loss of dopaminergic (DA) neurons during PD using current pharmacological treatment strategies is limited and remains challenging. Pluripotent stem cell-based regenerative medicine may offer a promising therapeutic alternative, although the medical application of human embryonic tissue and pluripotent stem cells is still a matter of ethical and practical debate. Addressing these challenges, the present study investigated the potential of adult human neural crest-derived stem cells derived from the inferior turbinate (ITSCs) transplanted into a parkinsonian rat model. Emphasizing their capability to give rise to nervous tissue, ITSCs isolated from the adult human nose efficiently differentiated into functional mature neurons in vitro. Additional successful dopaminergic differentiation of ITSCs was subsequently followed by their transplantation into a unilaterally lesioned 6-hydroxydopamine rat PD model. Transplantation of predifferentiated or undifferentiated ITSCs led to robust restoration of rotational behavior, accompanied by significant recovery of DA neurons within the substantia nigra. ITSCs were further shown to migrate extensively in loose streams primarily toward the posterior direction as far as to the midbrain region, at which point they were able to differentiate into DA neurons within the locus ceruleus. We demonstrate, for the first time, that adult human ITSCs are capable of functionally recovering a PD rat model.

  8. Concise reviews: Characteristics and potential applications of human dental tissue-derived mesenchymal stem cells.

    PubMed

    Liu, Junjun; Yu, Fang; Sun, Yao; Jiang, Beizhan; Zhang, Wenjun; Yang, Jianhua; Xu, Guo-Tong; Liang, Aibin; Liu, Shangfeng

    2015-03-01

    Recently, numerous types of human dental tissue-derived mesenchymal stem cells (MSCs) have been isolated and characterized, including dental pulp stem cells, stem cells from exfoliated deciduous teeth, periodontal ligament stem cells, dental follicle progenitor cells, alveolar bone-derived MSCs, stem cells from apical papilla, tooth germ progenitor cells, and gingival MSCs. All these MSC-like cells exhibit self-renewal, multilineage differentiation potential, and immunomodulatory properties. Several studies have demonstrated the potential advantages of dental stem cell-based approaches for regenerative treatments and immunotherapies. This review outlines the properties of various dental MSC-like populations and the progress toward their use in regenerative therapy. Several dental stem cell banks worldwide are also introduced, with a view toward future clinical application.

  9. Encapsulation of mesenchymal stem cells by bioscaffolds protects cell survival and attenuates neuroinflammatory reaction in injured brain tissue after transplantation.

    PubMed

    Sarnowska, Anna; Jablonska, Anna; Jurga, Marcin; Dainiak, Maria; Strojek, Lukasz; Drela, Katarzyna; Wright, Kathleen; Tripathi, Anuj; Kumar, Ashok; Jungvid, Hans; Lukomska, Barbara; Forraz, Nico; McGuckin, Colin; Domanska-Janik, Krystyna

    2013-01-01

    Since the brain is naturally inefficient in regenerating functional tissue after injury or disease, novel restorative strategies including stem cell transplantation and tissue engineering have to be considered. We have investigated the use of such strategies in order to achieve better functional repair outcomes. One of the fundamental challenges of successful transplantation is the delivery of cells to the injured site while maintaining cell viability. Classical cell delivery methods of intravenous or intraparenchymal injections are plagued by low engraftment and poor survival of transplanted stem cells. Novel implantable devices such as 3D bioactive scaffolds can provide the physical and metabolic support required for successful progenitor cell engraftment, proliferation, and maturation. In this study, we performed in situ analysis of laminin-linked dextran and gelatin macroporous scaffolds. We revealed the protective action of gelatin-laminin (GL) scaffolds seeded with mesenchymal stem cells derived from donated human Wharton's jelly (hUCMSCs) against neuroinflammatory reactions of injured mammalian brain tissue. These bioscaffolds have been implanted into (i) intact and (ii) ischemic rat hippocampal organotypic slices and into the striatum of (iii) normal and (iv) focally injured brains of adult Wistar rats. We found that transplantation of hUCMSCs encapsulated in GL scaffolds had a significant impact on the prevention of glial scar formation (low glial acidic fibrillary protein) and in the reduction of neuroinflammation (low interleukin-6 and the microglial markers ED1 and Iba1) in the recipient tissue. Moreover, implantation of hUCMSCs encapsulated within GL scaffolds induced matrix metalloproteinase-2 and -9 proteolytic activities in the surrounding brain tissue. This facilitated scaffold biodegradation while leaving the remaining grafted hUCMSCs untouched. In conclusion, transplanting GL scaffolds preseeded with hUCMSCs into mammalian brain tissue escaped

  10. Notch signalling inhibits the adipogenic differentiation of single-cell-derived mesenchymal stem cell clones isolated from human adipose tissue.

    PubMed

    Osathanon, Thanaphum; Subbalekha, Keskanya; Sastravaha, Panunn; Pavasant, Prasit

    2012-01-01

    ADSCs (adipose-derived mesenchymal stem cells) are candidate adult stem cells for regenerative medicine. Notch signalling participates in the differentiation of a heterogeneous ADSC population. We have isolated, human adipose tissue-derived single-cell clones using a cloning ring technique and characterized for their stem cell characteristics. The role of Notch signalling in the differentiation capacity of these adipose-derived single-cell-clones has also been investigated. All 14 clones expressed embryonic and mesenchymal stem cell marker genes. These clones could differentiate into both osteogenic and adipogenic lineages. However, the differentiation potential of each clone was different. Low adipogenic clones had significantly higher mRNA expression levels of Notch 2, 3 and 4, Jagged1, as well as Delta1, compared with those of high adipogenic clones. In contrast, no changes in expression of Notch signalling component mRNA between low and high osteogenic clones was found. Notch receptor mRNA expression decreased with the adipogenic differentiation of both low and high adipogenic clones. The γ-secretase inhibitor, DAPT (N-[N-(3,5-difluorophenacetyl)-l-alanyl]-(S)-phenylglycine t-butyl ester), enhanced adipogenic differentiation. Correspondingly, cells seeded on a Notch ligand (Jagged1) bound surface showed lower intracellular lipid accumulation. These results were noted in both low and high adipogenic clones, indicating that Notch signalling inhibited the adipogenic differentiation of adipose ADSC clones, and could be used to identify an adipogenic susceptible subpopulation for soft-tissue augmentation application.

  11. Adult Adipose-Derived Stem Cell Attachment to Biomaterials

    PubMed Central

    Prichard, Heather L; Reichert, William M; Klitzman, Bruce

    2007-01-01

    Attachment of adipose-derived stem cells (ASC) to biomaterials prior to implantation is a possible strategy for mediating inflammation and wound healing. In this study, the ASC percent coverage was measured on common medical grade biosensor materials subjected to different surface treatments. Cell coverage on silicone elastomer (poly dimethylsiloxane) was below 20% for all surface treatments. Polyimide (Kapton), polyurethane (Pellethane) and tissue culture polystyrene all exhibited >50% coverage for surfaces treated with fibronectin (Fn), fibronectin plus avidin/biotin (dual ligand), and oxygen plasma plus fibronectin treatments (Fn O2). The fibronectin treatment performed as well or better on polyimide, polyurethane, and tissue culture polystyrene compared to the dual ligand and fibronectin oxygen plasma treated surfaces. Cell detachment with increasing shear stresses was <25% for each attachment method on both polyimide and polyurethane. The effects of attachment methods on the basic cell functions of proliferation, metabolism, ATP concentration, and caspase-3 activity were analyzed yielding proliferation profiles that were very similar among all of the materials. No significant differences in metabolism, intracellular ATP, or intracellular caspase-3 activity were observed for any of the attachment methods on either polyimide or polyurethane. PMID:17074385

  12. Perinatal stem cells: A promising cell resource for tissue engineering of craniofacial bone

    PubMed Central

    Si, Jia-Wen; Wang, Xu-Dong; Shen, Steve GF

    2015-01-01

    In facing the mounting clinical challenge and suboptimal techniques of craniofacial bone defects resulting from various conditions, such as congenital malformations, osteomyelitis, trauma and tumor resection, the ongoing research of regenerative medicine using stem cells and concurrent advancement in biotechnology have shifted the focus from surgical reconstruction to a novel stem cell-based tissue engineering strategy for customized and functional craniofacial bone regeneration. Given the unique ontogenetical and cell biological properties of perinatal stem cells, emerging evidence has suggested these extraembryonic tissue-derived stem cells to be a promising cell source for extensive use in regenerative medicine and tissue engineering. In this review, we summarize the current achievements and obstacles in stem cell-based craniofacial bone regeneration and subsequently we address the characteristics of various types of perinatal stem cells and their novel application in tissue engineering of craniofacial bone. We propose the promising feasibility and scope of perinatal stem cell-based craniofacial bone tissue engineering for future clinical application. PMID:25621114

  13. Gastrointestinal stem cell up-to-date.

    PubMed

    Pirvulet, V

    2015-01-01

    Cellular and tissue regeneration in the gastrointestinal tract depends on stem cells with properties of self-renewal, clonogenicity, and multipotency. Progress in stem cell research and the identification of potential gastric, intestinal, colonic stem cells new markers and the signaling pathways provide hope for the use of stem cells in regenerative medicine and treatments for disease. This review provides an overview of the different types of stem cells, focusing on tissue-restricted adult stem cells.

  14. [Safety evaluation of tissue engineered medical devices using normal human mesenchymal stem cells].

    PubMed

    Sawada, Rumi; Ito, Tomomi; Tsuchiya, Toshie

    2007-05-01

    Several recent studies demonstrated the potential of bioengineering using somatic stem cells in regenerative medicine. Adult human mesenchymal stem cells (hMSCs) derived from bone marrow have the pluripotency to differentiate into cells of mesodermal origin, e.g., bone, cartilage, adipose, and muscle cells; they, therefore, have many potential clinical applications. On the other hand, stem cells possess a self-renewal capability similar to cancer cells. For safety evaluation of tissue engineered medical devices using normal hMSCs, in this study, we investigated the expression levels of several genes that affect cell proliferation in hMSCs during in vitro culture. We focused on the relationship between the hMSC proliferation and their transforming growth factor beta (TGFbeta) signaling during in vitro culture. The proliferation rate of hMSCs gradually decreased and cellular senescence was observed for about 3 months. The mRNA expressions of TGFbeta1, TGFbeta2, and TGFbeta receptor type I (TGFbetaRI) in hMSCs increased with the length of cell culture. The mRNA expressions of Smad3 increased, but those of c-myc and nucleostemin decreased with the length hMSCs were in in vitro culture. In addition, the expression profiles of the genes which regulate cellular proliferation in hMSCs were significantly different from those of cancer cells. In conclusion, hMSCs derived from bone marrow seldom underwent spontaneous transformation during 1-2 months in vitro culture for use in clinical applications. In hMSCs as well as in epithelial cells, growth might be controlled by the TGFbeta family signaling.

  15. Label-free identification and characterization of murine hair follicle stem cells located in thin tissue sections with Raman micro-spectroscopy.

    PubMed

    Tsai, Tsung-Hua; Short, Michael A; McLean, David I; Zeng, Haishan; McElwee, Kevin; Lui, Harvey

    2014-06-07

    Stem cells offer tremendous opportunities for regenerative medicine. Over the past decade considerable research has taken place to identify and characterize the differentiation states of stem cells in culture. Raman micro-spectroscopy has emerged as an ideal technology since it is fast, nondestructive, and does not require potentially toxic dyes. Raman spectroscopy systems can also be incorporated into confocal microscope imaging systems allowing spectra to be obtained from below the tissue surface. Thus there is significant potential for monitoring stem cells in living tissue. Stem cells that reside in hair follicles are suitable for testing this possibility since they are close to the skin surface, and typically clustered around the bulge area. One of the first steps needed would be to obtain Raman micro-spectra from stem cells located in thin sections of tissue, and then see whether these spectra are clearly different from those of the surrounding differentiated cells. To facilitate this test, standard 5 μm thick sections of murine skin tissue were stained to identify the location of hair follicle stem cells and their progeny. Raman spectra were then obtained from adjacent cells in a subsequent unstained 10 μm thick section. The spectra revealed significant differences in peak intensities associated with nucleic acids, proteins, lipids and amino acids. Statistical analyses of the Raman micro-spectra identified stem cells with 98% sensitivity and 94% specificity, as compared with a CD34 immunostaining gold standard. Furthermore analyses of the spectral variance indicated differences in cellular dynamics between the two cell groups. This study shows that Raman micro-spectroscopy has a potential role in identifying adult follicle stem cells, laying the groundwork for future applications of hair follicle stem cells and other somatic stem cells in situ.

  16. Tissue migration capability of larval and adult Brugia pahangi.

    PubMed

    Chirgwin, Sharon R; Coleman, Sharon U; Porthouse, Kristina H; Klei, Thomas R

    2006-02-01

    Infection with mosquito-born filarial nematodes occurs when hosts are bitten by a vector carrying the infective third stage larvae (L3) of the parasites. These larvae, deposited on the skin by the feeding mosquito, are presumed to enter the skin via the vector-induced puncture wound. Larvae of Brugia spp. must then migrate from the entry site, penetrate various skin layers, and locate a lymphatic vessel that leads to their lymphatic predilection site. We have recently established an intradermal (ID) infection model using B. pahangi and the Mongolian gerbil, allowing us to investigate the migratory capability ofB. pahangi. Larval and adult parasites recovered from the peritoneal cavities of gerbils were capable of establishing an infection following ID (larvae) or subcutaneous (adult) injection. Third and fourth stage larvae both migrated away from the injection site within hours, although data suggest they localize to different lymphatic tissues at 3 days postinfection (DPI). Immature adult (28 day) B. pahangi also migrated away from their SC inoculation site within 7 DPI. Mature (45 day) adult B. pahangi displayed little migration away from the SC infection site, suggesting tissue migration may be limited to developing stages of the parasite.

  17. Characterization of adipose tissue macrophages and adipose-derived stem cells in critical wounds

    PubMed Central

    Tilstam, Pathricia V.; Springenberg-Jung, Katrin; Boecker, Arne Hendrick; Schmitz, Corinna; Heinrichs, Daniel; Hwang, Soo Seok; Stromps, Jan Philipp; Ganse, Bergita; Kopp, Ruedger; Knobe, Matthias; Bernhagen, Juergen

    2017-01-01

    Background Subcutaneous adipose tissue is a rich source of adipose tissue macrophages and adipose-derived stem cells which both play a key role in wound repair. While macrophages can be divided into the classically-activated M1 and the alternatively-activated M2 phenotype, ASCs are characterized by the expression of specific stem cell markers. Methods In the present study, we have investigated the expression of common macrophage polarization and stem cell markers in acutely inflamed adipose tissue. Subcutaneous adipose tissue adjacent to acutely inflamed wounds of 20 patients and 20 healthy subjects were harvested and underwent qPCR and flow cytometry analysis. Results Expression levels of the M1-specific markers CD80, iNOS, and IL-1b were significantly elevated in inflammatory adipose tissue when compared to healthy adipose tissue, whereas the M2-specific markers CD163 and TGF-β were decreased. By flow cytometry, a significant shift of adipose tissue macrophage populations towards the M1 phenotype was confirmed. Furthermore, a decrease in the mesenchymal stem cell markers CD29, CD34, and CD105 was observed whereas CD73 and CD90 remained unchanged. Discussion This is the first report describing the predominance of M1 adipose tissue macrophages and the reduction of stem cell marker expression in acutely inflamed, non-healing wounds. PMID:28070458

  18. Stem cell and biomaterials research in dental tissue engineering and regeneration.

    PubMed

    Horst, Orapin V; Chavez, Miquella G; Jheon, Andrew H; Desai, Tejal; Klein, Ophir D

    2012-07-01

    This review summarizes approaches used in tissue engineering and regenerative medicine, with a focus on dental applications. Dental caries and periodontal disease are the most common diseases resulting in tissue loss. To replace or regenerate new tissues, various sources of stem cells have been identified such as somatic stem cells from teeth and peridontium. Advances in biomaterial sciences including microfabrication, self-assembled biomimetic peptides, and 3-dimensional printing hold great promise for whole-organ or partial tissue regeneration to replace teeth and periodontium.

  19. The effect of substrate stiffness on adult neural stem cell behavior.

    PubMed

    Leipzig, Nic D; Shoichet, Molly S

    2009-12-01

    Adult stem cells reside in unique niches that provide vital cues for their survival, self-renewal and differentiation. In order to better understand the contribution of substrate stiffness to neural stem/progenitor cell (NSPC) differentiation and proliferation, a photopolymerizable methacrylamide chitosan (MAC) biomaterial was developed. Photopolymerizable MAC is particularly compelling for the study of the central nervous system stem cell niche because Young's elastic modulus (E(Y)) can be tuned from less than 1 kPa to greater than 30 kPa. Additionally, the numerous free amine functional groups enable inclusion of biochemical signaling molecules that, together with the mechanical environment, influence cell behavior. Herein, NSPCs proliferated on MAC substrates with Young's elastic moduli below 10 kPa and exhibited maximal proliferation on 3.5 kPa surfaces. Neuronal differentiation was favored on the soft est surfaces with E(Y) < 1 kPa as confirmed by both immunohistochemistry and qRT-PCR. Oligodendrocyte differentiation was favored on stiffer scaffolds (> 7 kPa); however, myelin oligodendrocyte glycoprotein (MOG) gene expression suggested that oligodendrocyte maturation and myelination was best on < 1 kPa scaffolds where more mature neurons were present. Astrocyte differentiation was only observed on < 1 and 3.5 kPa surfaces and represented less than 2% of the total cell population. This work demonstrates the importance of substrate stiffness to the proliferation and differentiation of adult NSPCs and highlights the importance of mechanical properties to the success of scaffolds designed to engineer central nervous system tissue.

  20. Cerebellar stem cells do not produce neurons and astrocytes in adult mouse

    SciTech Connect

    Su, Xin; Guan, Wuqiang; Yu, Yong-Chun; Fu, Yinghui

    2014-07-18

    Highlights: • No new neurons and astrocytes are generated in adult mouse cerebellum. • Very few mash1{sup +} or nestin{sup +} stem cells exist, and most of them are quiescent. • Cell proliferation rate is diversified among cerebellar regions and decreases over time. - Abstract: Although previous studies implied that cerebellar stem cells exist in some adult mammals, little is known about whether these stem cells can produce new neurons and astrocytes. In this study by bromodeoxyuridine (BrdU) intraperitoneal (i.p.) injection, we found that there are abundant BrdU{sup +} cells in adult mouse cerebellum, and their quantity and density decreases significantly over time. We also found cell proliferation rate is diversified in different cerebellar regions. Among these BrdU{sup +} cells, very few are mash1{sup +} or nestin{sup +} stem cells, and the vast majority of cerebellar stem cells are quiescent. Data obtained by in vivo retrovirus injection indicate that stem cells do not produce neurons and astrocytes in adult mouse cerebellum. Instead, some cells labeled by retrovirus are Iba1{sup +} microglia. These results indicate that very few stem cells exist in adult mouse cerebellum, and none of these stem cells contribute to neurogenesis and astrogenesis under physiological condition.

  1. The role of CD44 in fetal and adult hematopoietic stem cell regulation.

    PubMed

    Cao, Huimin; Heazlewood, Shen Y; Williams, Brenda; Cardozo, Daniela; Nigro, Julie; Oteiza, Ana; Nilsson, Susan K

    2016-01-01

    Throughout development, hematopoietic stem cells migrate to specific microenvironments, where their fate is, in part, extrinsically controlled. CD44 standard as a member of the cell adhesion molecule family is extensively expressed within adult bone marrow and has been previously reported to play important roles in adult hematopoietic regulation via CD44 standard-ligand interactions. In this manuscript, CD44 expression and function are further assessed and characterized on both fetal and adult hematopoietic stem cells. Using a CD44(-/-) mouse model, conserved functional roles of CD44 are revealed throughout development. CD44 is critical in the maintenance of hematopoietic stem and progenitor pools, as well as in hematopoietic stem cell migration. CD44 expression on hematopoietic stem cells as well as other hematopoietic cells within the bone marrow microenvironment is important in the homing and lodgment of adult hematopoietic stem cells isolated from the bone/bone marrow interface. CD44 is also involved in fetal hematopoietic stem cell migration out of the liver, via a process involving stromal cell-derived factor-1α. The absence of CD44 in neonatal bone marrow has no impact on the size of the long-term reconstituting hematopoietic stem cell pool, but results in an enhanced long-term engraftment potential of hematopoietic stem cells.

  2. The role of CD44 in fetal and adult hematopoietic stem cell regulation

    PubMed Central

    Cao, Huimin; Heazlewood, Shen Y.; Williams, Brenda; Cardozo, Daniela; Nigro, Julie; Oteiza, Ana; Nilsson, Susan K.

    2016-01-01

    Throughout development, hematopoietic stem cells migrate to specific microenvironments, where their fate is, in part, extrinsically controlled. CD44 standard as a member of the cell adhesion molecule family is extensively expressed within adult bone marrow and has been previously reported to play important roles in adult hematopoietic regulation via CD44 standard-ligand interactions. In this manuscript, CD44 expression and function are further assessed and characterized on both fetal and adult hematopoietic stem cells. Using a CD44−/− mouse model, conserved functional roles of CD44 are revealed throughout development. CD44 is critical in the maintenance of hematopoietic stem and progenitor pools, as well as in hematopoietic stem cell migration. CD44 expression on hematopoietic stem cells as well as other hematopoietic cells within the bone marrow microenvironment is important in the homing and lodgment of adult hematopoietic stem cells isolated from the bone/bone marrow interface. CD44 is also involved in fetal hematopoietic stem cell migration out of the liver, via a process involving stromal cell-derived factor-1α. The absence of CD44 in neonatal bone marrow has no impact on the size of the long-term reconstituting hematopoietic stem cell pool, but results in an enhanced long-term engraftment potential of hematopoietic stem cells. PMID:26546504

  3. Energy metabolism and energy-sensing pathways in mammalian embryonic and adult stem cell fate

    PubMed Central

    Rafalski, Victoria A.; Mancini, Elena; Brunet, Anne

    2012-01-01

    Summary Metabolism is influenced by age, food intake, and conditions such as diabetes and obesity. How do physiological or pathological metabolic changes influence stem cells, which are crucial for tissue homeostasis? This Commentary reviews recent evidence that stem cells have different metabolic demands than differentiated cells, and that the molecular mechanisms that control stem cell self-renewal and differentiation are functionally connected to the metabolic state of the cell and the surrounding stem cell niche. Furthermore, we present how energy-sensing signaling molecules and metabolism regulators are implicated in the regulation of stem cell self-renewal and differentiation. Finally, we discuss the emerging literature on the metabolism of induced pluripotent stem cells and how manipulating metabolic pathways might aid cellular reprogramming. Determining how energy metabolism regulates stem cell fate should shed light on the decline in tissue regeneration that occurs during aging and facilitate the development of therapies for degenerative or metabolic diseases. PMID:23420198

  4. In vivo sensitivity of the embryonic and adult neural stem cell compartments to low-dose radiation

    PubMed Central

    Barazzuol, Lara; Jeggo, Penny A.

    2016-01-01

    The embryonic brain is radiation-sensitive, with cognitive deficits being observed after exposure to low radiation doses. Exposure of neonates to radiation can cause intracranial carcinogenesis. To gain insight into the basis underlying these outcomes, we examined the response of the embryonic, neonatal and adult brain to low-dose radiation, focusing on the neural stem cell compartments. This review summarizes our recent findings. At E13.5–14.5 the embryonic neocortex encompasses rapidly proliferating stem and progenitor cells. Exploiting mice with a hypomorphic mutation in DNA ligase IV (Lig4Y288C), we found a high level of DNA double-strand breaks (DSBs) at E14.5, which we attribute to the rapid proliferation. We observed endogenous apoptosis in Lig4Y288C embryos and in WT embryos following exposure to low radiation doses. An examination of DSB levels and apoptosis in adult neural stem cell compartments, the subventricular zone (SVZ) and the subgranular zone (SGZ) revealed low DSB levels in Lig4Y288C mice, comparable with the levels in differentiated neuronal tissues. We conclude that the adult SVZ does not incur high levels of DNA breakage, but sensitively activates apoptosis; apoptosis was less sensitively activated in the SGZ, and differentiated neuronal tissues did not activate apoptosis. P5/P15 mice showed intermediate DSB levels, suggesting that DSBs generated in the embryo can be transmitted to neonates and undergo slow repair. Interestingly, this analysis revealed a stage of high endogenous apoptosis in the neonatal SVZ. Collectively, these studies reveal that the adult neural stem cell compartment, like the embryonic counterpart, can sensitively activate apoptosis. PMID:27125639

  5. Isolation, in vitro culture and identification of a new type of mesenchymal stem cell derived from fetal bovine lung tissues.

    PubMed

    Hu, Pengfei; Pu, Yabin; Li, Xiayun; Zhu, Zhiqiang; Zhao, Yuhua; Guan, Weijun; Ma, Yuehui

    2015-09-01

    Lung‑derived mesenchymal stem cells (LMSCs) are considered to be important in lung tissue repair and regenerative processes. However, the biological characteristics and differentiation potential of LMSCs remain to be elucidated. In the present study, fetal lung‑derived mesenchymal stem cells (FLMSCs) were isolated from fetal bovine lung tissues by collagenase digestion. The in vitro culture conditions were optimized and stabilized and the self‑renewal ability and differentiation potential were evaluated. The results demonstrated that the FLMSCs were morphologically consistent with fibroblasts, were able to be cultured and passaged for at least 33 passages and the cell morphology and proliferative ability were stable during the first 10 passages. In addition, FLMSCs were found to express CD29, CD44, CD73 and CD166, however, they did not express hematopoietic cell specific markers, including CD34, CD45 and BOLA‑DRα. The growth kinetics of FLMSCs consisted of a lag phase, a logarithmic phase and a plateau phase, and as the passages increased, the proliferative ability of cells gradually decreased. The majority of FLMSCs were in G0/G1 phase. Following osteogenic induction, FLMSCs were positive for the expression of osteopontin and collagen type I α2. Following neurogenic differentiation, the cells were morphologically consistent with neuronal cells and positive for microtubule‑associated protein 2 and nestin expression. It was concluded that the isolated FLMSCs exhibited typical characteristics of mesenchymal stem cells and that the culture conditions were suitable for their proliferation and the maintenance of stemness. The present study illustrated the potential application of lung tissue as an adult stem cell source for regenerative therapies.

  6. Ultrasonic assessment of facial soft tissue thicknesses in adult Egyptians.

    PubMed

    El-Mehallawi, I H; Soliman, E M

    2001-03-01

    The production of a three-dimensional plastic face on an unknown human skull has been practiced sporadically since the latter part of the last century. In recent years, the technique has been revived and applied to forensic science cases. The morphometric method of forensic facial reconstruction rests heavily on the use of facial soft tissue depth measurements. Moreover, it has been established that measurements made on the living are of more value than those made on the dead. In view of the well-known genetic complexities of the Egyptians, and the lack of knowledge of average facial soft tissue depths of the Egyptians that makes facial reconstruction questionable, it was decided to set up a table of norms for facial tissue thicknesses in 204 adult Egyptians aged 20-35 years. Tissue depths at 17 established landmarks (according to Aulsebrook et al. [Forensic Sci. Int. 79 (1996) 83]) were obtained using ultrasonic probing. The study revealed a unique spectrum of measurements for the Egyptians that might be useful for facial reconstruction purposes with obvious sexual dimorphism in facial soft tissue thickness. Additionally, the study provided evidence for the presence of interpopulation differences in average facial soft tissue thicknesses as evidenced from the comparison of the present data of Egyptians with those previously reported for some other populations.

  7. The adult pituitary shows stem/progenitor cell activation in response to injury and is capable of regeneration.

    PubMed

    Fu, Qiuli; Gremeaux, Lies; Luque, Raul M; Liekens, Daisy; Chen, Jianghai; Buch, Thorsten; Waisman, Ari; Kineman, Rhonda; Vankelecom, Hugo

    2012-07-01

    The pituitary gland constitutes, together with the hypothalamus, the regulatory core of the endocrine system. Whether the gland is capable of cell regeneration after injury, in particular when suffered at adult age, is unknown. To investigate the adult pituitary's regenerative capacity and the response of its stem/progenitor cell compartment to damage, we constructed a transgenic mouse model to conditionally destroy pituitary cells. GHCre/iDTR mice express diphtheria toxin (DT) receptor after transcriptional activation by Cre recombinase, which is driven by the GH promoter. Treatment with DT for 3 d leads to gradual GH(+) (somatotrope) cell obliteration with a final ablation grade of 80-90% 1 wk later. The stem/progenitor cell-clustering side population promptly expands after injury, concordant with the immediate increase in Sox2(+) stem/progenitor cells. In addition, folliculo-stellate cells, previously designated as pituitary stem/progenitor cells and significantly overlapping with Sox2(+) cells, also increase in abundance. In situ examination reveals expansion of the Sox2(+) marginal-zone niche and appearance of remarkable Sox2(+) cells that contain GH. When mice are left after the DT-provoked lesion, GH(+) cells considerably regenerate during the following months. Double Sox2(+)/GH(+) cells are observed throughout the regenerative period, suggesting recovery of somatotropes from stem/progenitor cells, as further supported by 5-ethynyl-2'-deoxyuridine (EdU) pulse-chase lineage tracing. In conclusion, our study demonstrates that the adult pituitary gland holds regenerative competence and that tissue repair follows prompt activation and plausible involvement of the stem/progenitor cells.

  8. Thyroid Hormone-Induced Activation of Notch Signaling is Required for Adult Intestinal Stem Cell Development During Xenopus Laevis Metamorphosis.

    PubMed

    Hasebe, Takashi; Fujimoto, Kenta; Kajita, Mitsuko; Fu, Liezhen; Shi, Yun-Bo; Ishizuya-Oka, Atsuko

    2016-11-21

    In Xenopus laevis intestine during metamorphosis, the larval epithelial cells are removed by apoptosis, and the adult epithelial stem (AE) cells appear concomitantly. They proliferate and differentiate to form the adult epithelium (Ep). Thyroid hormone (TH) is well established to trigger this remodeling by regulating the expression of various genes including Notch receptor. To study the role of Notch signaling, we have analyzed the expression of its components, including the ligands (DLL and Jag), receptor (Notch), and targets (Hairy), in the metamorphosing intestine by real-time reverse transcription-polymerase chain reaction and in situ hybridization or immunohistochemistry. We show that they are up-regulated during both natural and TH-induced metamorphosis in a tissue-specific manner. Particularly, Hairy1 is specifically expressed in the AE cells. Moreover, up-regulation of Hairy1 and Hairy2b by TH was prevented by treating tadpoles with a γ-secretase inhibitor (GSI), which inhibits Notch signaling. More importantly, TH-induced up-regulation of LGR5, an adult intestinal stem cell marker, was suppressed by GSI treatment. Our results suggest that Notch signaling plays a role in stem cell development by regulating the expression of Hairy genes during intestinal remodeling. Furthermore, we show with organ culture experiments that prolonged exposure of tadpole intestine to TH plus GSI leads to hyperplasia of secretory cells and reduction of absorptive cells. Our findings here thus provide evidence for evolutionarily conserved role of Notch signaling in intestinal cell fate determination but more importantly reveal, for the first time, an important role of Notch pathway in the formation of adult intestinal stem cells during vertebrate development. Stem Cells 2016.

  9. Regenerative potential of the cartilaginous tissue in mesenchymal stem cells: update, limitations, and challenges.

    PubMed

    Cruz, Ivana Beatrice Mânica da; Severo, Antônio Lourenço; Azzolin, Verônica Farina; Garcia, Luiz Filipe Machado; Kuhn, André; Lech, Osvandré

    2017-01-01

    Advances in the studies with adult mesenchymal stem cells (MSCs) have turned tissue regenerative therapy into a promising tool in many areas of medicine. In orthopedics, one of the main challenges has been the regeneration of cartilage tissue, mainly in diarthroses. In the induction of the MSCs, in addition to cytodifferentiation, the microenvironmental context of the tissue to be regenerated and an appropriate spatial arrangement are extremely important factors. Furthermore, it is known that MSC differentiation is fundamentally determined by mechanisms such as cell proliferation (mitosis), biochemical-molecular interactions, movement, cell adhesion, and apoptosis. Although the use of MSCs for cartilage regeneration remains at a research level, there are important questions to be resolved in order to make this therapy efficient and safe. It is known, for instance, that the expansion of chondrocytes in cultivation, needed to increase the number of cells, could end up producing fibrocartilage instead of hyaline cartilage. However, the latest results are promising. In 2014, the first stage I/II clinical trial to evaluate the efficacy and safety of the intra-articular injection of MSCs in femorotibial cartilage regeneration was published, indicating a decrease in injured areas. One issue to be explored is how many modifications in the articulate inflammatory environment could induce differentiation of MSCs already allocated in that region. Such issue arose from studies that suggested that the suppression of the inflammation may increase the efficiency of tissue regeneration. Considering the complexity of the events related to the chondrogenesis and cartilage repair, it can be concluded that the road ahead is still long, and that further studies are needed.

  10. [The application progress of human urine derived stem cells in bone tissue engineering].

    PubMed

    Gao, Peng; Jiang, Dapeng; Li, Zhaozhu

    2016-04-01

    The research of bone tissue engineering bases on three basic directions of seed cells, scaffold materials and growth information. Stem cells have been widely studied as seed cells. Human urine-derived stem cell (hUSC) is extracted from urine and described to be adhesion growth, cloning, expression of the majority of mesenchymal stem cell markers and peripheral cell markers, multi-potential and no tumor but stable karyotype with passaging many times. Some researches proposed that hUSC might be a new source of seed cells in tissue engineering because of their invasive and convenient obtention, stable culture and multiple differentiation potential.

  11. Platelet-Rich Blood Derivatives for Stem Cell-Based Tissue Engineering and Regeneration

    PubMed Central

    Kaushik, Gaurav; Leijten, Jeroen; Khademhosseini, Ali

    2016-01-01

    Platelet rich blood derivatives have been widely used in different fields of medicine and stem cell based tissue engineering. They represent natural cocktails of autologous growth factor, which could provide an alternative for recombinant protein based approaches. Platelet rich blood derivatives, such as platelet rich plasma, have consistently shown to potentiate stem cell proliferation, migration, and differentiation. Here, we review the spectrum of platelet rich blood derivatives, discuss their current applications in tissue engineering and regenerative medicine, reflect on their effect on stem cells, and highlight current translational challenges. PMID:27047733

  12. Stem Cell Therapy for Healing Wounded Skin and Soft Tissues

    DTIC Science & Technology

    2012-07-01

    Cells (MSC) Aggregates 1. Synthesis and Culture of Rabbit MSC Aggregates One of our objectives in the proposed study is to understand the paracrine... aggregates via a forced aggregation technique usingmicropatterned wells (AggreWellTM, STEMCELL Technologies) originally developed for embryonic...stem ceUs (ESC)/ induced pluripotent stem cells (iPS) research. We were capable of producing cell aggregates of different sizes ranging fi·om 125 cells

  13. Concise review: tailoring bioengineered scaffolds for stem cell applications in tissue engineering and regenerative medicine.

    PubMed

    Cosson, Steffen; Otte, Ellen A; Hezaveh, Hadi; Cooper-White, Justin J

    2015-02-01

    The potential for the clinical application of stem cells in tissue regeneration is clearly significant. However, this potential has remained largely unrealized owing to the persistent challenges in reproducibly, with tight quality criteria, and expanding and controlling the fate of stem cells in vitro and in vivo. Tissue engineering approaches that rely on reformatting traditional Food and Drug Administration-approved biomedical polymers from fixation devices to porous scaffolds have been shown to lack the complexity required for in vitro stem cell culture models or translation to in vivo applications with high efficacy. This realization has spurred the development of advanced mimetic biomaterials and scaffolds to increasingly enhance our ability to control the cellular microenvironment and, consequently, stem cell fate. New insights into the biology of stem cells are expected to eventuate from these advances in material science, in particular, from synthetic hydrogels that display physicochemical properties reminiscent of the natural cell microenvironment and that can be engineered to display or encode essential biological cues. Merging these advanced biomaterials with high-throughput methods to systematically, and in an unbiased manner, probe the role of scaffold biophysical and biochemical elements on stem cell fate will permit the identification of novel key stem cell behavioral effectors, allow improved in vitro replication of requisite in vivo niche functions, and, ultimately, have a profound impact on our understanding of stem cell biology and unlock their clinical potential in tissue engineering and regenerative medicine.

  14. Evolution of normal and neoplastic tissue stem cells: progress after Robert Hooke.

    PubMed

    Weissman, Irving

    2015-10-19

    The appearance of stem cells coincides with the transition from single-celled organisms to metazoans. Stem cells are capable of self-renewal as well as differentiation. Each tissue is maintained by self-renewing tissue-specific stem cells. The accumulation of mutations that lead to preleukaemia are in the blood-forming stem cell, while the transition to leukaemia stem cells occurs in the clone at a progenitor stage. All leukaemia and cancer cells escape being removed by scavenger macrophages by expressing the 'don't eat me' signal CD47. Blocking antibodies to CD47 are therapeutics for all cancers, and are currently being tested in clinical trials in the US and UK.

  15. Limbal Stromal Tissue Specific Stem Cells and Their Differentiation Potential to Corneal Epithelial Cells.

    PubMed

    Katikireddy, Kishore Reddy; Jurkunas, Ula V

    2016-01-01

    From the derivation of the first human embryonic stem (hES) cell line to the development of induced pluripotent stem (iPS) cells; it has become evident that tissue specific stem cells are able to differentiate into a specific somatic cell types. The understanding of key processes such as the signaling pathways and the role of the microenvironment in epidermal/epithelial development has provided important clues for the derivation of specific epithelial cell types.Various differentiation protocols/methods were used to attain specific epithelial cell types. Here, we describe in detail the procedure to follow for isolation of tissue specific stem cells, mimicking their microenvironment to attain stem cell characteristics, and their potential differentiation to corneal epithelial cells.

  16. Evolution of normal and neoplastic tissue stem cells: progress after Robert Hooke

    PubMed Central

    Weissman, Irving

    2015-01-01

    The appearance of stem cells coincides with the transition from single-celled organisms to metazoans. Stem cells are capable of self-renewal as well as differentiation. Each tissue is maintained by self-renewing tissue-specific stem cells. The accumulation of mutations that lead to preleukaemia are in the blood-forming stem cell, while the transition to leukaemia stem cells occurs in the clone at a progenitor stage. All leukaemia and cancer cells escape being removed by scavenger macrophages by expressing the 'don't eat me' signal CD47. Blocking antibodies to CD47 are therapeutics for all cancers, and are currently being tested in clinical trials in the US and UK. PMID:26416675

  17. Free Amino Acid Contents of Stem and Phylloxera Gall Tissue Cultures of Grape 1

    PubMed Central

    Warick, R. P.; Hildebrandt, A. C.

    1966-01-01

    Free amino acid constituents were determined of grape stem and Phylloxera leaf gall callus in tissue culture. Fast, medium and slow growing single cell clones of, respectively, stem and gall origins were grown on a mineral salt-sucrose medium supplemented with coconut milk and α-naphthaleneacetic acid. Stem and gall clones showed qualitative similarities and quantitative variations in the amino acids and nitrogenous constituents. Nineteen amino acids, glucosamine, ethanolamine, sarcosine, methionine sulfoxides and ammonia were identified. Two free polypeptides accounted for over 30% of the amino compounds in the stem and gall callus tissues which were not found in the intact plant parts. Stem clones of different growth rates grown on agar showed generally an excess of amino acid constituents over gall tissues of similar growth rates, except for the free polypeptides. Fast growing stem clones grown on agar medium contained lower amounts of certain amino acids than the fast growing gall clones, but when grown in liquid medium they contained higher amounts of these acids than the gall clones. The total and nonsoluble nitrogen of stem clones were higher than in the gall clones. Tissue cultures differed from the original plant parts with respect to their free polypeptides and high amino acid contents. Images PMID:16656290

  18. Sox9 modulates cell survival and adipogenic differentiation of multipotent adult rat mesenchymal stem cells.

    PubMed

    Stöckl, Sabine; Bauer, Richard J; Bosserhoff, Anja K; Göttl, Claudia; Grifka, Joachim; Grässel, Susanne

    2013-07-01

    Sox9 is a key transcription factor in early chondrogenesis with distinct roles in differentiation processes and during embryonic development. Here, we report that Sox9 modulates cell survival and contributes to the commitment of mesenchymal stem cells (MSC) to adipogenic or osteogenic differentiation lineages. We found that the Sox9 activity level affects the expression of the key transcription factor in adipogenic differentiation, C/EBPβ, and that cyclin D1 mediates the expression of the osteogenic marker osteocalcin in undifferentiated adult bone-marrow-derived rat MSC. Introducing a stable Sox9 knockdown into undifferentiated rat MSC resulted in a marked decrease in proliferation rate and an increase in apoptotic activity. This was linked to a profound upregulation of p21 and cyclin D1 gene and protein expression accompanied by an induction of caspase 3/7 activity and an inhibition of Bcl-2. We observed that Sox9 silencing provoked a delayed S-phase progression and an increased nuclear localization of p21. The protein stability of cyclin D1 was induced in the absence of Sox9 presumably as a function of altered p38 signalling. In addition, the major transcription factor for adipogenic differentiation, C/EBPβ, was repressed after silencing Sox9. The nearly complete absence of C/EBPβ protein as a result of increased destabilization of the C/EBPβ mRNA and the impact on osteocalcin gene expression and protein synthesis, suggests that a delicate balance of Sox9 level is not only imperative for proper chondrogenic differentiation of progenitor cells, but also affects the adipogenic and probably osteogenic differentiation pathways of MSC. Our results identified Sox9 as an important link between differentiation, proliferation and apoptosis in undifferentiated adult rat mesenchymal stem cells, emphasizing the importance of the delicate balance of a precisely regulated Sox9 activity in MSC not only for proper skeletal development during embryogenesis but probably also

  19. Engineering complex tissue-like microgel arrays for evaluating stem cell differentiation

    PubMed Central

    Guermani, Enrico; Shaki, Hossein; Mohanty, Soumyaranjan; Mehrali, Mehdi; Arpanaei, Ayyoob; Gaharwar, Akhilesh K.; Dolatshahi-Pirouz, Alireza

    2016-01-01

    Development of tissue engineering scaffolds with native-like biology and microarchitectures is a prerequisite for stem cell mediated generation of off-the-shelf-tissues. So far, the field of tissue engineering has not full-filled its grand potential of engineering such combinatorial scaffolds for engineering functional tissues. This is primarily due to the many challenges associated with finding the right microarchitectures and ECM compositions for optimal tissue regeneration. Here, we have developed a new microgel array to address this grand challenge through robotic printing of complex stem cell-laden microgel arrays. The developed microgel array platform consisted of various microgel environments that where composed of native-like cellular microarchitectures resembling vascularized and bone marrow tissue architectures. The feasibility of our array system was demonstrated through localized cell spreading and osteogenic differentiation of human mesenchymal stem cells (hMSCs) into complex tissue-like structures. In summary, we have developed a tissue-like microgel array for evaluating stem cell differentiation within complex and heterogeneous cell microenvironments. We anticipate that the developed platform will be used for high-throughput identification of combinatorial and native-like scaffolds for tissue engineering of functional organs. PMID:27465860

  20. Evidence of progenitor cells of glandular and myoepithelial cell lineages in the human adult female breast epithelium: a new progenitor (adult stem) cell concept.

    PubMed

    Boecker, Werner; Buerger, Horst

    2003-10-01

    Although experimental data clearly confirm the existence of self-renewing mammary stem cells, the characteristics of such progenitor cells have never been satisfactorily defined. Using a double immunofluorescence technique for simultaneous detection of the basal cytokeratin 5, the glandular cytokeratins 8/18 and the myoepithelial differentiation marker smooth muscle actin (SMA), we were able to demonstrate the presence of CK5+ cells in human adult breast epithelium. These cells have the potential to differentiate to either glandular (CK8/18+) or myoepithelial cells (SMA+) through intermediary cells (CK5+ and CK8/18+ or SMA+). We therefore proceeded on the assumption that the CK5+ cells are phenotypically and behaviourally progenitor (committed adult stem) cells of human breast epithelium. Furthermore, we furnish evidence that most of these progenitor cells are located in the luminal epithelium of the ductal lobular tree. Based on data obtained in extensive analyses of proliferative breast disease lesions, we have come to regard usual ductal hyperplasia as a progenitor cell-derived lesion, whereas most breast cancers seem to evolve from differentiated glandular cells. Double immunofluorescence experiments provide a new tool to characterize phenotypically progenitor (adult stem) cells and their progenies. This model has been shown to be of great value for a better understanding not only of normal tissue regeneration but also of proliferative breast disease. Furthermore, this model provides a new tool for unravelling further the regulatory mechanisms that govern normal and pathological cell growth.

  1. Tissue Engineering for Bone Production- Stem Cells, Gene Therapy and Scaffolds

    PubMed Central

    Khaled, E.G; Saleh, M; Hindocha, S; Griffin, M; Khan, Wasim S

    2011-01-01

    A bone graft has been the gold standard treatment for repairing bone defects. However, due to bone grafts associated donor site morbidity several alternative bone substitutes options have been made available but with their added expense and limited osteoinductive properties they are not ideal. Therefore, research has begun in tissue engineering to investigate stem cells, which are one of the body’s own mechanisms used to repair bone. Stem cells are clonogenic undifferentiated cells capable of self-renewal. Readily available from numerous of sources stem cells have the potential to differentiate in osteoblasts and chrondrocytes showing capability to repair both bone and cartilage. The known immunologic properties of stem cells further enhance their therapeutic appeal. Stem cells have shown to be excellent carriers for gene transfer having the capability to be transduced. Gene transfer could enable growth factors and bone morphogentic proteins to enhance bone repair. Stem cells are implanted onto scaffolds, which are structures capable of supporting tissue formation by allowing cell migration, proliferation and differentiation. Research aims to produce scaffolds that deliver and retain cells, allow for cell attachment has adequate biodegradability, biocompatibility and non-immunogenicity. However, having tried and testing numerous materials including synthetic and natural products research into the perfect scaffold product continues. This review aims to explain how stem cells were discovered, the techniques used to isolate stem cells, identify and manipulate them down different cell lineages and discuss the research into using stem cells to reconstruct bone using genetic modification and scaffolds. PMID:21886695

  2. Adult Stem Cells from the Hyaluronic Acid-Rich Node and Duct System Differentiate into Neuronal Cells and Repair Brain Injury

    PubMed Central

    Lee, Seung J.; Park, Sang H.; Kim, Yu I.; Hwang, Sunhee; Kwon, Patrick M.; Han, In S.

    2014-01-01

    The existence of a hyaluronic acid-rich node and duct system (HAR-NDS) within the lymphatic and blood vessels was demonstrated previously. The HAR-NDS was enriched with small (3.0–5.0 μm in diameter), adult stem cells with properties similar to those of the very small embryonic-like stem cells (VSELs). Sca-1+Lin−CD45− cells were enriched approximately 100-fold in the intravascular HAR-NDS compared with the bone marrow. We named these adult stem cells “node and duct stem cells (NDSCs).” NDSCs formed colonies on C2C12 feeder layers, were positive for fetal alkaline phosphatase, and could be subcultured on the feeder layers. NDSCs were Oct4+Nanog+SSEA-1+Sox2+, while VSELs were Oct4+Nanog+SSEA-1+Sox2−. NDSCs had higher sphere-forming efficiency and proliferative potential than VSELs, and they were found to differentiate into neuronal cells in vitro. Injection of NDSCs into mice partially repaired ischemic brain damage. Thus, we report the discovery of potential adult stem cells that may be involved in tissue regeneration. The intravascular HAR-NDS may serve as a route that delivers these stem cells to their target tissues. PMID:25027245

  3. Characterization and Differentiation of Stem Cells Isolated from Human Newborn Foreskin Tissue.

    PubMed

    Somuncu, Özge Sezin; Taşlı, Pakize Neslihan; Şişli, Hatice Burcu; Somuncu, Salih; Şahin, Fikrettin

    2015-11-01

    Circumcision is described as a cultural, medical, and religious process which states surgical removal of the foreskin either partly or fully. Cells isolated from the circumcised tissues are referred as foreskin cells. They have been thought as feeder cell lines for embryonic stem cells. Their fibroblastic properties were also utilized for several experiments. The waste tissues that remain after the circumcision thought to have stem cell properties. Therefore, there have been very few attempts to expose their stem cell properties without turning them into induced pluripotent stem cells. Although stem cell isolation from prepuce and their mesenchymal multilineage differentiation potential have been presented many times in the literature, the current study explored hematopoietical phenotype of newborn foreskin stem cells for the first time. According to the results, human newborn foreskin stem cells (hnFSSCs) were identified by their capability to turn into all three germ layer cell types under in vitro conditions. In addition, these cells have exhibited a stable phenotype and have remained as a monolayer in vitro. hnFSSCs suggested to carry different treatment potentials for bone damages, cartilage problems, nerve damages, lesion formations, and other diseases that are derive from mesodermal, endodermal, and ectodermal origins. Owing to the location of the tissue in the body and differentiation capabilities of hnFSSCs, these cells can be considered as easily obtainable and utilizable even better than the other stem cell sources. In addition, hnFSSCs offers a great potential for tissue engineering approaches due to exhibiting embryonic stem cell-like characteristics, not having any ethical issues, and teratoma induction as in embryonic stem cell applications.

  4. Surface functionalization of nanobiomaterials for application in stem cell culture, tissue engineering, and regenerative medicine.

    PubMed

    Rana, Deepti; Ramasamy, Keerthana; Leena, Maria; Jiménez, Constanza; Campos, Javier; Ibarra, Paula; Haidar, Ziyad S; Ramalingam, Murugan

    2016-05-01

    Stem cell-based approaches offer great application potential in tissue engineering and regenerative medicine owing to their ability of sensing the microenvironment and respond accordingly (dynamic behavior). Recently, the combination of nanobiomaterials with stem cells has paved a great way for further exploration. Nanobiomaterials with engineered surfaces could mimic the native microenvironment to which the seeded stem cells could adhere and migrate. Surface functionalized nanobiomaterial-based scaffolds could then be used to regulate or control the cellular functions to culture stem cells and regenerate damaged tissues or organs. Therefore, controlling the interactions between nanobiomaterials and stem cells is a critical factor. However, surface functionalization or modification techniques has provided an alternative approach for tailoring the nanobiomaterials surface in accordance to the physiological surrounding of a living cells; thereby, enhancing the structural and functional properties of the engineered tissues and organs. Currently, there are a variety of methods and technologies available to modify the surface of biomaterials according to the specific cell or tissue properties to be regenerated. This review highlights the trends in surface modification techniques for nanobiomaterials and the biological relevance in stem cell-based tissue engineering and regenerative medicine. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:554-567, 2016.

  5. Roles of neural stem cells and adult neurogenesis in adolescent alcohol use disorders.

    PubMed

    Nixon, Kimberly; Morris, Stephanie A; Liput, Daniel J; Kelso, Matthew L

    2010-02-01

    This review discusses the contributions of a newly considered form of plasticity, the ongoing production of new neurons from neural stem cells, or adult neurogenesis, within the context of neuropathologies that occur with excessive alcohol intake in the adolescents. Neural stem cells and adult neurogenesis are now thought to contribute to the structural integrity of the hippocampus, a limbic system region involved in learning, memory, behavioral control, and mood. In adolescents with alcohol use disorders (AUDs), the hippocampus appears to be particularly vulnerable to the neurodegenerative effects of alcohol, but the role of neural stem cells and adult neurogenesis in alcoholic neuropathology has only recently been considered. This review encompasses a brief overview of neural stem cells and the processes involved in adult neurogenesis, how neural stem cells are affected by alcohol, and possible differences in the neurogenic niche between adults and adolescents. Specifically, what is known about developmental differences in adult neurogenesis between the adult and adolescent is gleaned from the literature, as well as how alcohol affects this process differently among the age groups. Finally, this review suggests differences that may exist in the neurogenic niche between adults and adolescents and how these differences may contribute to the susceptibility of the adolescent hippocampus to damage. However, many more studies are needed to discern whether these developmental differences contribute to the vulnerability of the adolescent to developing an AUD.

  6. Epistatic adult plant resistance in wheat to stem rust cosegregates with Sr12 seedling resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat adult plant resistance (APR) to stem rust is desirable. Researchers have characterized the inheritance of APR in cultivar Thatcher as complex. In order to identify the loci providing APR in Thatcher, we evaluated 160 RILs derived from Thatcher/McNeal for stem rust reaction in the field in Keny...

  7. Nanomaterial scaffolds for stem cell proliferation and differentiation in tissue engineering.

    PubMed

    Zhao, Chunyan; Tan, Aaron; Pastorin, Giorgia; Ho, Han Kiat

    2013-01-01

    Tissue engineering is a clinically driven field and has emerged as a potential alternative to organ transplantation. The cornerstone of successful tissue engineering rests upon two essential elements: cells and scaffolds. Recently, it was found that stem cells have unique capabilities of self-renewal and multilineage differentiation to serve as a versatile cell source, while nanomaterials have lately emerged as promising candidates in producing scaffolds able to better mimic the nanostructure in natural extracellular matrix and to efficiently replace defective tissues. This article, therefore, reviews the key developments in tissue engineering, where the combination of stem cells and nanomaterial scaffolds has been utilized over the past several years. We consider the high potential, as well as the main issues related to the application of stem cells and nanomaterial scaffolds for a range of tissues including bone, cartilage, nerve, liver, eye etc. Promising in vitro results such as efficient attachment, proliferation and differentiation of stem cells have been compiled in a series of examples involving different nanomaterials. Furthermore, the merits of the marriage of stem cells and nanomaterial scaffolds are also demonstrated in vivo, providing early successes to support subsequent clinical investigations. This progress simultaneously drives mechanistic research into the mechanotransduction process responsible for the observations in order to optimize the process further. Current understanding is chiefly reported to involve the interaction of stem cells and the anchoring nanomaterial scaffolds by activating various signaling pathways. Substrate surface characteristics and scaffold bulk properties are also reported to influence not only short term stem cell adhesion, spreading and proliferation, but also longer term lineage differentiation, functionalization and viability. It is expected that the combination of stem cells and nanomaterials will develop into an

  8. 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.

  9. Role of nanotopography in the development of tissue engineered 3D organs and tissues using mesenchymal stem cells

    PubMed Central

    Salmasi, Shima; Kalaskar, Deepak M; Yoon, Wai-Weng; Blunn, Gordon W; Seifalian, Alexander M

    2015-01-01

    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. PMID:25815114

  10. Transcriptome Analysis of Stem and Globally Comparison with Other Tissues in Brassica napus

    PubMed Central

    Miao, Liyun; Zhang, Libin; Raboanatahiry, Nadia; Lu, Guangyuan; Zhang, Xuekun; Xiang, Jun; Gan, Jianping; Fu, Chunhua; Li, Maoteng

    2016-01-01

    Brassica napus is one of the most important oilseed crops in the world. However, there is currently no enough stem transcriptome information and comparative transcriptome analysis of different tissues, which impedes further functional genomics research on B. napus. In this study, the stem transcriptome of B. napus was characterized by RNA-seq technology. Approximately 13.4 Gb high-quality clean reads with an average length of 100 bp were generated and used for comparative transcriptome analysis with the existing transcriptome sequencing data of roots, leaves, flower buds, and immature embryos of B. napus. All the transcripts were annotated against GO and KEGG databases. The common genes in five tissues, differentially expressed genes (DEGs) of the common genes between stems and other tissues, and tissue-specific genes were detected, and the main biochemical activities and pathways implying the common genes, DEGs and tissue-specific genes were investigated. Accordingly, the common transcription factors (TFs) in the five tissues and tissue-specific TFs were identified, and a TFs-based regulation network between TFs and the target genes involved in ‘Phenylpropanoid biosynthesis’ pathway were constructed to show several important TFs and key nodes in the regulation process. Collectively, this study not only provided an available stem transcriptome resource in B. napus, but also revealed valuable comparative transcriptome information of five tissues of B. napus for future investigation on specific processes, functions and pathways. PMID:27708656

  11. Cranial irradiation induces bone marrow-derived microglia in adult mouse brain tissue.

    PubMed

    Okonogi, Noriyuki; Nakamura, Kazuhiro; Suzuki, Yoshiyuki; Suto, Nana; Suzue, Kazutomo; Kaminuma, Takuya; Nakano, Takashi; Hirai, Hirokazu

    2014-07-01

    Postnatal hematopoietic progenitor cells do not contribute to microglial homeostasis in adult mice under normal conditions. However, previous studies using whole-body irradiation and bone marrow (BM) transplantation models have shown that adult BM cells migrate into the brain tissue and differentiate into microglia (BM-derived microglia; BMDM). Here, we investigated whether cranial irradiation alone was sufficient to induce the generation of BMDM in the adult mouse brain. Transgenic mice that express green fluorescent protein (GFP) under the control of a murine stem cell virus (MSCV) promoter (MSCV-GFP mice) were used. MSCV-GFP mice express GFP in BM cells but not in the resident microglia in the brain. Therefore, these mice allowed us to detect BM-derived cells in the brain without BM reconstitution. MSCV-GFP mice, aged 8-12 weeks, received 13.0 Gy irradiation only to the cranium, and BM-derived cells in the brain were quantified at 3 and 8 weeks after irradiation. No BM-derived cells were detected in control non-irradiated MSCV-GFP mouse brains, but numerous GFP-labeled BM-derived cells were present in the brain stem, basal ganglia and cerebral cortex of the irradiated MSCV-GFP mice. These BM-derived cells were positive for Iba1, a marker for microglia, indicating that GFP-positive BM-derived cells were microglial in nature. The population of BMDM was significantly greater at 8 weeks post-irradiation than at 3 weeks post-irradiation in all brain regions examined. Our results clearly show that cranial irradiation alone is sufficient to induce the generation of BMDM in the adult mouse.

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

    PubMed

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

    2013-05-01

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

  13. Mature adipocytes may be a source of stem cells for tissue engineering

    SciTech Connect

    Fernyhough, M.E.; Hausman, G.J.; Guan, L.L.; Okine, E.; Moore, S.S.; Dodson, M.V.

    2008-04-11

    Adipose tissue contains a large portion of stem cells. These cells appear morphologically like fibroblasts and are primarily derived from the stromal cell fraction. Mature (lipid-filled) adipocytes possess the ability to become proliferative cells and have been shown to produce progeny cells that possess the same morphological (fibroblast-like) appearance as the stem cells from the stromal fraction. A closer examination of mature adipocyte-derived progeny cells may prove to be an emerging area of growth/metabolic physiology that may modify present thinking about adipose tissue renewal capabilities. Knowledge of these cells may also prove beneficial in cell-based therapies for tissue repair, regeneration, or engineering.

  14. Adult Bone Marrow Neural Crest Stem Cells and Mesenchymal Stem Cells Are Not Able to Replace Lost Neurons in Acute MPTP-Lesioned Mice

    PubMed Central

    Neirinckx, Virginie; Marquet, Alice; Coste, Cécile

    2013-01-01

    Adult bone marrow stroma contains multipotent stem cells (BMSC) that are a mixed population of mesenchymal and neural-crest derived stem cells. Both cells are endowed with in vitro multi-lineage differentiation abilities, then constituting an attractive and easy-available source of material for cell therapy in neurological disorders. Whereas the in vivo integration and differentiation of BMSC in neurons into the central nervous system is currently matter of debate, we report here that once injected into the striatum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice, pure populations of either bone marrow neural crest stem cells (NCSC) or mesenchymal stem cells (MSC) survived only transiently into the lesioned brain. Moreover, they do not migrate through the brain tissue, neither modify their initial phenotype, while no recovery of the dopaminergic system integrity was observed. Consequently, we tend to conclude that MSC/NCSC are not able to replace lost neurons in acute MPTP-lesioned dopaminergic system through a suitable integration and/or differentiation process. Altogether with recent data, it appears that neuroprotective, neurotrophic and anti-inflammatory features characterizing BMSC are of greater interest as regards CNS lesions management. PMID:23741377

  15. Adult bone marrow-derived stem cells for organ regeneration and repair.

    PubMed

    Tögel, Florian; Westenfelder, Christof

    2007-12-01

    Stem cells have been recognized as a potential tool for the development of innovative therapeutic strategies. There are in general two types of stem cells, embryonic and adult stem cells. While embryonic stem cell therapy has been riddled with problems of allogeneic rejection and ethical concerns, adult stem cells have long been used in the treatment of hematological malignancies. With the recognition of additional, potentially therapeutic characteristics, bone marrow-derived stem cells have become a tool in regenerative medicine. The bone marrow is an ideal source of stem cells because it is easily accessible and harbors two types of stem cells. Hematopoietic stem cells give rise to all blood cell types and have been shown to exhibit plasticity, while multipotent marrow stromal cells are the source of osteocytes, chondrocytes, and fat cells and have been shown to support and generate a large number of different cell types. This review describes the general characteristics of these stem cell populations and their current and potential future applications in regenerative medicine.

  16. Developmental stage-dependent effects of cardiac fibroblasts on function of stem cell-derived engineered cardiac tissues

    PubMed Central

    Liau, Brian; Jackman, Christopher P.; Li, Yanzhen; Bursac, Nenad

    2017-01-01

    We investigated whether the developmental stage of mouse cardiac fibroblasts (CFs) influences the formation and function of engineered cardiac tissues made of mouse embryonic stem cell-derived cardiomyocytes (mESC-CMs). Engineered cardiac tissue patches were fabricated by encapsulating pure mESC-CMs, mESC-CMs + adult CFs, or mESC-CMs + fetal CFs in fibrin-based hydrogel. Tissue patches containing fetal CFs exhibited higher velocity of action potential propagation and contractile force amplitude compared to patches containing adult CFs, while pure mESC-CM patches did not form functional syncytium. The functional improvements in mESC-CM + fetal CF patches were associated with differences in structural remodeling and increased expression of proteins involved in cardiac function. To determine role of paracrine signaling, we cultured pure mESC-CMs within miniature tissue “micro-patches” supplemented with media conditioned by adult or fetal CFs. Fetal CF-conditioned media distinctly enhanced CM spreading and contractile activity, which was shown by pathway inhibitor experiments and Western blot analysis to be mediated via MEK-ERK signaling. In mESC-CM monolayers, CF-conditioned media did not alter CM spreading or MEK-ERK activation. Collectively, our studies show that 3D co-culture of mESC-CMs with embryonic CFs is superior to co-culture with adult CFs for in vitro generation of functional myocardium. Ensuring consistent developmental stages of cardiomyocytes and supporting non-myocytes may be a critical factor for promoting functional maturation of engineered cardiac tissues. PMID:28181589

  17. Gene delivery techniques for adult stem cell-based regenerative therapy.

    PubMed

    Seo, Seog-Jin; Kim, Tae-Hyun; Choi, Seong-Jun; Park, Jeong-Hui; Wall, Ivan B; Kim, Hae-Won

    2013-11-01

    Over the past decade, stem cells have been considered to be a promising resource to cure and regenerate damaged or diseased tissues with research extending from basic studies to clinical application. Furthermore, genetically modified stem cells have the potential to reduce tumorigenic risks and achieve safe tissue formation. Recent advances in genetic modification of stem cells have rendered these cells more accessible and stable. The successful genetic modification of stem cells relies heavily on designing vector systems, either viral or nonviral vectors, which can efficiently deliver therapeutic genes to the cells with minimum toxicity. Currently, viral vectors showing high transfection efficiencies still raise safety issues, whereas safer nonviral vectors exhibit extremely poor transfection in stem cells. Here, we attempt to review and discuss the main factors raising concern in previous reports, and devise strategies to solve the issues in gene delivery systems for successful stem cell-targeting regenerative therapy.

  18. Detection, Characterization, and Spontaneous Differentiation In Vitro of Very Small Embryonic-Like Putative Stem Cells in Adult Mammalian Ovary

    PubMed Central

    Parte, Seema; Telang, Jyoti; Daithankar, Vinita; Salvi, Vinita; Zaveri, Kusum; Hinduja, Indira

    2011-01-01

    The present study was undertaken to detect, characterize, and study differentiation potential of stem cells in adult rabbit, sheep, monkey, and menopausal human ovarian surface epithelium (OSE). Two distinct populations of putative stem cells (PSCs) of variable size were detected in scraped OSE, one being smaller and other similar in size to the surrounding red blood cells in the scraped OSE. The smaller 1–3 μm very small embryonic-like PSCs were pluripotent in nature with nuclear Oct-4 and cell surface SSEA-4, whereas the bigger 4–7 μm cells with cytoplasmic localization of Oct-4 and minimal expression of SSEA-4 were possibly the tissue committed progenitor stem cells. Pluripotent gene transcripts of Oct-4, Oct-4A, Nanog, Sox-2, TERT, and Stat-3 in human and sheep OSE were detected by reverse transcriptase–polymerase chain reaction. The PSCs underwent spontaneous differentiation into oocyte-like structures, parthenote-like structures, embryoid body-like structures, cells with neuronal-like phenotype, and embryonic stem cell-like colonies, whereas the epithelial cells transformed into mesenchymal phenotype by epithelial–mesenchymal transition in 3 weeks of OSE culture. Germ cell markers like c-Kit, DAZL, GDF-9, VASA, and ZP4 were immuno-localized in oocyte-like structures. In conclusion, as opposed to the existing view of OSE being a bipotent source of oocytes and granulosa cells, mammalian ovaries harbor distinct very small embryonic-like PSCs and tissue committed progenitor stem cells population that have the potential to develop into oocyte-like structures in vitro, whereas mesenchymal fibroblasts appear to form supporting granulosa-like somatic cells. Research at the single-cell level, including complete gene expression profiling, is required to further confirm whether postnatal oogenesis is a conserved phenomenon in adult mammals. PMID:21291304

  19. Detection, characterization, and spontaneous differentiation in vitro of very small embryonic-like putative stem cells in adult mammalian ovary.

    PubMed

    Parte, Seema; Bhartiya, Deepa; Telang, Jyoti; Daithankar, Vinita; Salvi, Vinita; Zaveri, Kusum; Hinduja, Indira

    2011-08-01

    The present study was undertaken to detect, characterize, and study differentiation potential of stem cells in adult rabbit, sheep, monkey, and menopausal human ovarian surface epithelium (OSE). Two distinct populations of putative stem cells (PSCs) of variable size were detected in scraped OSE, one being smaller and other similar in size to the surrounding red blood cells in the scraped OSE. The smaller 1-3 μm very small embryonic-like PSCs were pluripotent in nature with nuclear Oct-4 and cell surface SSEA-4, whereas the bigger 4-7 μm cells with cytoplasmic localization of Oct-4 and minimal expression of SSEA-4 were possibly the tissue committed progenitor stem cells. Pluripotent gene transcripts of Oct-4, Oct-4A, Nanog, Sox-2, TERT, and Stat-3 in human and sheep OSE were detected by reverse transcriptase-polymerase chain reaction. The PSCs underwent spontaneous differentiation into oocyte-like structures, parthenote-like structures, embryoid body-like structures, cells with neuronal-like phenotype, and embryonic stem cell-like colonies, whereas the epithelial cells transformed into mesenchymal phenotype by epithelial-mesenchymal transition in 3 weeks of OSE culture. Germ cell markers like c-Kit, DAZL, GDF-9, VASA, and ZP4 were immuno-localized in oocyte-like structures. In conclusion, as opposed to the existing view of OSE being a bipotent source of oocytes and granulosa cells, mammalian ovaries harbor distinct very small embryonic-like PSCs and tissue committed progenitor stem cells population that have the potential to develop into oocyte-like structures in vitro, whereas mesenchymal fibroblasts appear to form supporting granulosa-like somatic cells. Research at the single-cell level, including complete gene expression profiling, is required to further confirm whether postnatal oogenesis is a conserved phenomenon in adult mammals.

  20. Integrin expression in stem cells from bone marrow and adipose tissue during chondrogenic differentiation.

    PubMed

    Goessler, Ulrich Reinhart; Bugert, Peter; Bieback, Karen; Stern-Straeter, Jens; Bran, Gregor; Hörmann, Karl; Riedel, Frank

    2008-03-01

    The use of adult mesenchymal stem cells (MSC) in cartilage tissue engineering offers new perspectives in the generation of transplants for reconstructive surgery. The extracelular matrix (ECM) plays a key role in modulating the function and phenotype of the embedded cells and contains the integrins as adhesion receptors mediating cell-cell and cell-matrix interactions. In our study, characteristic changes in integrin expression during the course of chondrogenic differentiation of MSC from bone marrow and adipose tissue were compared. MSC were isolated from bone marrow biopsies and adipose tissue. During cell culture, chondrogenic differentiation was performed. The expression of integrins and their signaling components were analysed with microarray and immunohistochemistry in freshly isolated MSC and after chondrogenic differentiation. The fibronectin receptor (integrin alpha5beta1) was expressed by undifferentiated MSC, and expression rose during chondrogenic differentiation in both types of MSC. The components of the vitronectin/osteopontin receptors (alphavbeta5) were not expressed by freshly isolated MSC, and expression rose with ongoing differentiation. Receptors for the collagens (alpha1beta1, alpha2beta1, alpha3beta1) were weakly expressed by undifferentiated MSC and were activated during differentiation. Intracellular signaling components integrin-linked kinase (ILK) and CD47 showed increased expression with ongoing differentiation. For all integrins, no significant differences were be found in the 2 types of MSC. Integrin-mediated signaling appeared to play an important role in the generation and maintenance of the chondrocytic phenotype during chondrogenic differentiation. Particularly, the receptors for fibronectin, vitronectin, osteopontin and the collagens may be involved in the generation of the ECM. Intracellularly, their signals might be transduced by ILK and CD47. To fully harness the potential of these cells, future studies should be directed to

  1. Paper-based bioactive scaffolds for stem cell-mediated bone tissue engineering.

    PubMed

    Park, Hyun-Ji; Yu, Seung Jung; Yang, Kisuk; Jin, Yoonhee; Cho, Ann-Na; Kim, Jin; Lee, Bora; Yang, Hee Seok; Im, Sung Gap; Cho, Seung-Woo

    2014-12-01

    Bioactive, functional scaffolds are required to improve the regenerative potential of stem cells for tissue reconstruction and functional recovery of damaged tissues. Here, we report a paper-based bioactive scaffold platform for stem cell culture and transplantation for bone reconstruction. The paper scaffolds are surface-engineered by an initiated chemical vapor deposition process for serial coating of a water-repellent and cell-adhesive polymer film, which ensures the long-term stability in cell culture medium and induces efficient cell attachment. The prepared paper scaffolds are compatible with general stem cell culture and manipulation techniques. An optimal paper type is found to provide structural, physical, and mechanical cues to enhance the osteogenic differentiation of human adipose-derived stem cells (hADSCs). A bioactive paper scaffold significantly enhances in vivo bone regeneration of hADSCs in a critical-sized calvarial bone defect. Stacking the paper scaffolds with osteogenically differentiated hADSCs and human endothelial cells resulted in vascularized bone formation in vivo. Our study suggests that paper possesses great potential as a bioactive, functional, and cost-effective scaffold platform for stem cell-mediated bone tissue engineering. To the best of our knowledge, this is the first study reporting the feasibility of a paper material for stem cell application to repair tissue defects.

  2. Isolation, cultivation, and characterization of adult murine prostate stem cells

    PubMed Central

    Lukacs, Rita U.; Goldstein, Andrew S.; Lawson, Devon A.; Cheng, Donghui; Witte, Owen N.

    2010-01-01

    ABSTRACT/SUMMARY The successful isolation and cultivation of prostate stem cells will allow us to study their unique biological properties and their application in therapeutic approaches. Here we provide step-by-step procedures on the basis of previous work in our laboratory for: the harvesting of primary prostate cells from adolescent male mice by a modified enzymatic procedure; the isolation of an enriched population of prostate stem cells through cell sorting; the cultivation of prostate stem cells in vitro; and characterization of these cells and their stem-like activity, including in vivo tubule regeneration. Normally it will take approximately 8 hours to harvest prostate cells, isolate the stem cell enriched population, and set up the in vitro sphere assay. It will take up to 8 weeks to analyze the unique properties of the stem cells, including their regenerative capacity in vivo. PMID:20360765

  3. Isolation, cultivation and characterization of adult murine prostate stem cells.

    PubMed

    Lukacs, Rita U; Goldstein, Andrew S; Lawson, Devon A; Cheng, Donghui; Witte, Owen N

    2010-04-01

    The successful isolation and cultivation of prostate stem cells will allow us to study their unique biological properties and their application in therapeutic approaches. Here we describe step-by-step procedures on the basis of previous work in our laboratory for the harvesting of primary prostate cells from adolescent male mice by a modified enzymatic procedure; the isolation of an enriched population of prostate stem cells through cell sorting; and the cultivation of prostate stem cells in vitro and characterization of these cells and their stem-like activity, including in vivo tubule regeneration. Normally, it will take approximately 8 h to harvest prostate cells, isolate the stem cell-enriched population and set up the in vitro sphere assay. It will take up to 8 weeks to analyze the unique properties of the stem cells, including their regenerative capacity in vivo.

  4. Hematopoietic stem and progenitor cells: their mobilization and homing to bone marrow and peripheral tissue.

    PubMed

    Schulz, Christian; von Andrian, Ulrich H; Massberg, Steffen

    2009-01-01

    Hematopoietic stem and progenitor cells (HSPCs) are a rare population of precursor cells that possess the capacity for self-renewal and multilineage differentiation. In the bone marrow (BM), HSPCs warrant blood cell homeostasis. In addition, they may also replenish tissue-resident myeloid cells and directly participate in innate immune responses once they home to peripheral tissues. In this review, we summarize recent data on the signaling molecules that modulate the mobilization of HSPCs from BM and their migration to peripheral tissues.

  5. Cell Supermarket: Adipose Tissue as a Source of Stem Cells

    PubMed Central

    Dodson, M.V.; Wei, S.; Duarte, M.; Du, M.; Jiang, Z.; Hausman, G.J.; Bergen, W.G.

    2013-01-01

    Adipose tissue is derived from numerous sources, and in recent years this tissue has been shown to provide numerous cells from what seemingly was a population of homogeneous adipocytes. Considering the types of cells that adipose tissue-derived cells may form, these cells may be useful in a variety of clinical and scientific applications. The focus of this paper is to reflect on this area of research and to provide a list of potential (future) research areas. PMID:25031654

  6. RNA-Seq Reveals the Angiogenesis Diversity between the Fetal and Adults Bone Mesenchyme Stem Cell.

    PubMed

    Zhao, Xin; Han, Yingmin; Liang, Yu; Nie, Chao; Wang, Jian

    2016-01-01

    In this research, we used RNA sequencing (RNA-seq) to analyze 23 single cell samples and 2 bulk cells sample from human adult bone mesenchyme stem cell line and human fetal bone mesenchyme stem cell line. The results from the research demonstrated that there were big differences between two cell lines. Adult bone mesenchyme stem cell lines showed a strong trend on the blood vessel differentiation and cell motion, 48/49 vascular related differential expressed genes showed higher expression in adult bone mesenchyme stem cell lines (Abmsc) than fetal bone mesenchyme stem cell lines (Fbmsc). 96/106 cell motion related genes showed the same tendency. Further analysis showed that genes like ANGPT1, VEGFA, FGF2, PDGFB and PDGFRA showed higher expression in Abmsc. This work showed cell heterogeneity between human adult bone mesenchyme stem cell line and human fetal bone mesenchyme stem cell line. Also the work may give an indication that Abmsc had a better potency than Fbmsc in the future vascular related application.

  7. CRIPTO/GRP78 Signaling Maintains Fetal and Adult Mammary Stem Cells Ex Vivo

    PubMed Central

    Spike, Benjamin T.; Kelber, Jonathan A.; Booker, Evan; Kalathur, Madhuri; Rodewald, Rose; Lipianskaya, Julia; La, Justin; He, Marielle; Wright, Tracy; Klemke, Richard; Wahl, Geoffrey M.; Gray, Peter C.

    2014-01-01

    Summary Little is known about the extracellular signaling factors that govern mammary stem cell behavior. Here, we identify CRIPTO and its cell-surface receptor GRP78 as regulators of stem cell behavior in isolated fetal and adult mammary epithelial cells. We develop a CRIPTO antagonist that promotes differentiation and reduces self-renewal of mammary stem cell-enriched populations cultured ex vivo. By contrast, CRIPTO treatment maintains the stem cell phenotype in these cultures and yields colonies with enhanced mammary gland reconstitution capacity. Surface expression of GRP78 marks CRIPTO-responsive, stem cell-enriched fetal and adult mammary epithelial cells, and deletion of GRP78 from adult mammary epithelial cells blocks their mammary gland reconstitution potential. Together, these findings identify the CRIPTO/GRP78 pathway as a developmentally conserved regulator of fetal and adult mammary stem cell behavior ex vivo, with implications for the stem-like cells found in many cancers. PMID:24749068

  8. Three-dimensional tissues using human pluripotent stem cell spheroids as biofabrication building blocks.

    PubMed

    Lin, Haishuang; Li, Qiang; Lei, Yuguo

    2017-03-13

    A recently emerged approach for tissue engineering is to biofabricate tissues using cellular spheroids as building blocks. Human pluripotent stem cells (hPSCs), including human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs), can be cultured to generate large numbers of cells and presumably be differentiated into all the cell types of human body in vitro, thus are ideal cell source for biofabrication. We previously developed a hydrogel-based cell culture system that can economically produce large numbers of hPSC spheroids. With hPSCs and this culture system, there are two potential methods to biofabricate a desired tissue. In Method 1, hPSC spheroids are first utilized to biofabricate a hPSC tissue that is subsequently differentiated into the desired tissue. In Method 2, hPSC spheroids are first converted into tissue spheroids in the hydrogel-based culture system and the tissue spheroids are then utilized to biofabricate the desired tissue. In this paper, we systematically measured the fusion rates of hPSC spheroids without and with differentiation toward cortical and midbrain dopaminergic neurons and found spheroids' fusion rates dropped sharply as differentiation progressed. We found Method 1 was appropriated for biofabricating neural tissues.

  9. Does the adult human ciliary body epithelium contain "true" retinal stem cells?

    PubMed

    Frøen, Rebecca; Johnsen, Erik O; Nicolaissen, Bjørn; Facskó, Andrea; Petrovski, Goran; Moe, Morten C

    2013-01-01

    Recent reports of retinal stem cells being present in several locations of the adult eye have sparked great hopes that they may be used to treat the millions of people worldwide who suffer from blindness as a result of retinal disease or injury. A population of proliferative cells derived from the ciliary body epithelium (CE) has been considered one of the prime stem cell candidates, and as such they have received much attention in recent years. However, the true nature of these cells in the adult human eye has still not been fully elucidated, and the stem cell claim has become increasingly controversial in light of new and conflicting reports. In this paper, we will try to answer the question of whether the available evidence is strong enough for the research community to conclude that the adult human CE indeed harbors stem cells.

  10. Dental and Nondental Stem Cell Based Regeneration of the Craniofacial Region: A Tissue Based Approach

    PubMed Central

    Hughes, Declan; Song, Bing

    2016-01-01

    Craniofacial reconstruction may be a necessary treatment for those who have been affected by trauma, disease, or pathological developmental conditions. The use of stem cell therapy and tissue engineering shows massive potential as a future treatment modality. Currently in the literature, there is a wide variety of published experimental studies utilising the different stem cell types available and the plethora of available scaffold materials. This review investigates different stem cell sources and their unique characteristics to suggest an ideal cell source for regeneration of individual craniofacial tissues. At present, understanding and clinical applications of stem cell therapy remain in their infancy with numerous challenges to overcome. In spite of this, the field displays immense capacity and will no doubt be utilised in future clinical treatments of craniofacial regeneration. PMID:27143979

  11. Regulation of stem cell plasticity: mechanisms and relevance to tissue biology and cancer.

    PubMed

    Strauss, Robert; Hamerlik, Petra; Lieber, André; Bartek, Jiri

    2012-05-01

    Embryonic stem cells (ESCs) are associated with a high degree of plasticity, which allows them to self-renew and differentiate into every somatic cell. During differentiation, ESCs follow a hierarchically organized pattern towards tissue specificity, which ultimately results in permanent cell cycle arrest and a loss of cellular plasticity. In contrast to their normal somatic counterparts, cancer cells retain elevated levels of plasticity that include switches between epithelial and mesenchymal phenotypes. Transitions between these cell stages have lately been linked to the reacquisition of stem cell features during cellular reprogramming and dedifferentiation in normal and neoplastic cells. In this review, we discuss the key factors and their interplay that is needed to regain a stem cell stage with a particular emphasis put on the impact of cell cycle regulation. Apart from mechanistic insights into the emerging fundamental processes of stem cell plasticity and capacity to transdifferentiate, we also highlight implications of these concepts for tissue biology, tumorigenesis, and cancer therapy.

  12. Cell supermarket: Adipose tissue as a source of stem cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adipose tissue is derived from numerous sources, and in recent years has been shown to provide numerous cells from what seemingly was a population of homogeneous adipocytes. Considering the types of cells that adipose tissue-derived cells may form, these cells may be useful in a variety of clinical ...

  13. [Establishment of induced pluripotent stem cells from adipose tissue-derived stem cells for dendritic cell-based cancer vaccines].

    PubMed

    Matsushita, Norimasa; Kobayashi, Hajime; Aruga, Atsushi; Yamamoto, Masakazu

    2014-04-01

    Recently, studies on regenerative stem cell therapy are being encouraged, and efforts to generate dendritic cells, which play important roles in cancer immunotherapy, from stem cells are being made in the field of tumor immunology. Therapeutic acquisition of stem cells has important clinical applications. Studies on induced pluripotent stem(iPS)cells generated from somatic cells with pluripotent genes have advanced in recent years. Stem cells are reported to be found in adipose tissue (adipose-derived stem cells, ADSC). Our goal is to develop a new cancer vaccine by using dendritic cells generated from ADSC. In a preliminary study, we examined whether iPS cells can be generated from ADSC to serve as a source of dendritic cells.We introduced a plasmid with pluripotent genes(OCT3/4, KLF4, SOX2, L-MYC, LIN28, p53-shRNA)into an ADSC strain derived from adipose tissue by electroporation and subsequently cultured the cells for further examination. A colony sugges- tive of iPS cells from ADSC was observed. OCT3/4, KLF4, SOX2, L-MYC, and LIN28 mRNAs were expressed in the cultured cells, as confirmed by reverse transcriptase-polymerase chain reaction(RT-PCR). On the basis of these results, we confirmed that iPS cells were generated from ADSC. The method of inducing dendritic cells from iPS cells has already been reported, and the results of this study suggest that ADSC is a potential source of dendritic cells.

  14. Stem Cells and Progenitor Cells for Tissue-Engineered Solutions to Congenital Heart Defects

    PubMed Central

    Gao, Yang; Jacot, Jeffrey G

    2015-01-01

    Synthetic patches and fixed grafts currently used in the repair of congenital heart defects are nonliving, noncontractile, and not electrically responsive, leading to increased risk of complication, reoperation, and sudden cardiac death. Studies suggest that tissue-engineered patches made from living, functional cells could grow with the patient, facilitate healing, and help recover cardiac function. In this paper, we review the research into possible sources of cardiomyocytes and other cardiac cells, including embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells, adipose-derived stem cells, umbilical cord blood cells, amniotic fluid-derived stem cells, and cardiac progenitor cells. Each cell source has advantages, but also has technical hurdles to overcome, including heterogeneity, functional maturity, immunogenicity, and pathogenicity. Additionally, biomaterials used as patch materials will need to attract and support desired cells and induce minimal immune responses. PMID:26379417

  15. Stem Cells

    MedlinePlus

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

  16. T-cell suicide gene therapy prompts thymic renewal in adults after hematopoietic stem cell transplantation.

    PubMed

    Vago, Luca; Oliveira, Giacomo; Bondanza, Attilio; Noviello, Maddalena; Soldati, Corrado; Ghio, Domenico; Brigida, Immacolata; Greco, Raffaella; Lupo Stanghellini, Maria Teresa; Peccatori, Jacopo; Fracchia, Sergio; Del Fiacco, Matteo; Traversari, Catia; Aiuti, Alessandro; Del Maschio, Alessandro; Bordignon, Claudio; Ciceri, Fabio; Bonini, Chiara

    2012-08-30

    The genetic modification of T cells with a suicide gene grants a mechanism of control of adverse reactions, allowing safe infusion after partially incompatible hematopoietic stem cell transplantation (HSCT). In the TK007 clinical trial, 22 adults with hematologic malignancies experienced a rapid and sustained immune recovery after T cell-depleted HSCT and serial infusions of purified donor T cells expressing the HSV thymidine kinase suicide gene (TK+ cells). After a first wave of circulating TK+ cells, the majority of T cells supporting long-term immune reconstitution did not carry the suicide gene and displayed high numbers of naive lymphocytes, suggesting the thymus-dependent development of T cells, occurring only upon TK+ -cell engraftment. Accordingly, after the infusions, we documented an increase in circulating TCR excision circles and CD31+ recent thymic emigrants and a substantial expansion of the active thymic tissue as shown by chest tomography scans. Interestingly, a peak in the serum level of IL-7 was observed after each infusion of TK+ cells, anticipating the appearance of newly generated T cells. The results of the present study show that the infusion of genetically modified donor T cells after HSCT can drive the recovery of thymic activity in adults, leading to immune reconstitution.

  17. Designer Self-Assembling Peptide Nanofiber Scaffolds for Adult Mouse Neural Stem Cell 3-Dimensional Cultures

    PubMed Central

    Gelain, Fabrizio; Bottai, Daniele; Vescovi, Angleo; Zhang, Shuguang

    2006-01-01

    Biomedical researchers have become increasingly aware of the limitations of conventional 2-dimensional tissue cell culture systems, including coated Petri dishes, multi-well plates and slides, to fully address many critical issues in cell biology, cancer biology and neurobiology, such as the 3-D microenvironment, 3-D gradient diffusion, 3-D cell migration and 3-D cell-cell contact interactions. In order to fully understand how cells behave in the 3-D body, it is important to develop a well-controlled 3-D cell culture system where every single ingredient is known. Here we report the development of a 3-D cell culture system using a designer peptide nanofiber scaffold with mouse adult neural stem cells. We attached several functional motifs, including cell adhesion, differentiation and bone marrow homing motifs, to a self-assembling peptide RADA16 (Ac-RADARADARADARADA-COHN2). These functionalized peptides undergo self-assembly into a nanofiber structure similar to Matrigel. During cell culture, the cells were fully embedded in the 3-D environment of the scaffold. Two of the peptide scaffolds containing bone marrow homing motifs significantly enhanced the neural cell survival without extra soluble growth and neurotrophic factors to the routine cell culture media. In these designer scaffolds, the cell populations with β-Tubulin+, GFAP+ and Nestin+ markers are similar to those found in cell populations cultured on Matrigel. The gene expression profiling array experiments showed selective gene expression, possibly involved in neural stem cell adhesion and differentiation. Because the synthetic peptides are intrinsically pure and a number of desired function cellular motifs are easy to incorporate, these designer peptide nanofiber scaffolds provide a promising controlled 3-D culture system for diverse tissue cells, and are useful as well for general molecular and cell biology. PMID:17205123

  18. Liver Progenitors Isolated from Adult Healthy Mouse Liver Efficiently Differentiate to Functional Hepatocytes In Vitro and Repopulate Liver Tissue.

    PubMed

    Tanimizu, Naoki; Ichinohe, Norihisa; Ishii, Masayuki; Kino, Junichi; Mizuguchi, Toru; Hirata, Koichi; Mitaka, Toshihiro

    2016-12-01

    It has been proposed that tissue stem cells supply multiple epithelial cells in mature tissues and organs. However, it is unclear whether tissue stem cells generally contribute to cellular turnover in normal healthy organs. Here, we show that liver progenitors distinct from bipotent liver stem/progenitor cells (LPCs) persistently exist in mouse livers and potentially contribute to tissue maintenance. We found that, in addition to LPCs isolated as EpCAM(+) cells, liver progenitors were enriched in CD45(-) TER119(-) CD31(-) EpCAM(-) ICAM-1(+) fraction isolated from late-fetal and postnatal livers. ICAM-1(+) liver progenitors were abundant by 4 weeks (4W) after birth. Although their number decreased with age, ICAM-1(+) liver progenitors existed in livers beyond that stage. We established liver progenitor clones derived from ICAM-1(+) cells between 1 and 20W and found that those clones efficiently differentiated into mature hepatocytes (MHs), which secreted albumin, eliminated ammonium ion, stored glycogen, and showed cytochrome P450 activity. Even after long-term culture, those clones kept potential to differentiate to MHs. When ICAM-1(+) clones were transplanted into nude mice after retrorsine treatment and 70% partial hepatectomy, donor cells were incorporated into liver plates and expressed hepatocyte nuclear factor 4α, CCAAT/enhancer binding protein α, and carbamoylphosphate synthetase I. Moreover, after short-term treatment with oncostatin M, ICAM-1(+) clones could efficiently repopulate the recipient liver tissues. Our results indicate that liver progenitors that can efficiently differentiate to MHs exist in normal adult livers. Those liver progenitors could be an important source of new MHs for tissue maintenance and repair in vivo, and for regenerative medicine ex vivo. Stem Cells 2016;34:2889-2901.

  19. Adipose tissue derived mesenchymal stem cells for musculoskeletal repair in veterinary medicine

    PubMed Central

    Arnhold, Stefan; Wenisch, Sabine

    2015-01-01

    Adipose tissue derived stem cells (ASCs) are mesenchymal stem cells which can be obtained from different adipose tissue sources within the body. It is an abundant cell pool, which is easy accessible and the cells can be obtained in large numbers, cultivated and expanded in vitro and prepared for tissue engineering approaches, especially for skeletal tissue repair. In the recent years this cell population has attracted a great amount of attention among researchers in human as well as in veterinary medicine. In the meantime ASCs have been well characterized and their use in regenerative medicine is very well established. This review focuses on the characterization of ASCs for their use for tissue engineering approaches especially in veterinary medicine and also highlights a selection of clinical trials on the basis of ASCs as the relevant cell source. PMID:25973326

  20. Progress in the tissue engineering and stem cell industry "are we there yet?".

    PubMed

    Jaklenec, Ana; Stamp, Andrea; Deweerd, Elizabeth; Sherwin, Angela; Langer, Robert

    2012-06-01

    This report presents a detailed update to our 2008 publication on the tissue engineering (TE) and stem cell industry. Data are reported through mid 2011 showing an almost three-fold growth in commercial sales over the past 4 years. In addition, the number of companies selling products or offering services has increased over two-fold to 106, and they are generating a remarkable $3.5 billion in sales. Overall, the TE and stem cell sector is spending $3.6 billion and employing almost 14,000 employees. These data suggest the TE and stem cell industry has stabilized and is on a path pointing toward continued success.

  1. Dedifferentiated adipocyte-derived progeny cells (DFAT cells): Potential stem cells of adipose tissue.

    PubMed

    Wei, Shengjuan; Zan, Linsen; Hausman, Gary J; Rasmussen, Theodore P; Bergen, Werner G; Dodson, Michael V

    2013-07-01

    Analyses of mature adipocytes have shown that they possess a reprogramming ability in vitro, which is associated with dedifferentiation. The subsequent dedifferentiated fat cells (DFAT cells) are multipotent and can differentiate into adipocytes and other cell types as well. Mature adipocytes can be easily obtained by biopsy, and the cloned progeny cells are homogeneous in vitro. Therefore, DFAT cells (a new type of stem cell) may provide an excellent source of cells for tissue regeneration, engineering and disease treatment. The dedifferentiation of mature adipocytes, the multipotent capacity of DFAT cells and comparisons and contrasts with mesenchymal stem cells (MSCs) and induced pluripotent stem cells (iPS) are discussed in this review.

  2. Vanillin attenuates negative effects of ultraviolet A on the stemness of human adipose tissue-derived mesenchymal stem cells.

    PubMed

    Lee, Sang Yeol; Park, See-Hyoung; Kim, Mi Ok; Lim, Inhwan; Kang, Mingyeong; Oh, Sae Woong; Jung, Kwangseon; Jo, Dong Gyu; Cho, Il-Hoon; Lee, Jongsung

    2016-10-01

    Ultraviolet A (UVA) irradiation induces various changes in cell biology. The objective of this study was to determine the effect of vanillin on UVA irradiation-induced damages in the stemness properties of human adipose tissue-derived mesenchymal stem cells (hAMSCs). UVA-antagonizing mechanisms of vanillin were also examined. The results revealed that vanillin attenuated UVA-induced reduction of the proliferative potential and stemness of hAMSCs evidenced by increased proliferative activity in BrdU incorporation assay and upregulation of stemness-related genes (OCT4, NANOG and SOX2) in response to vanillin treatment. UVA-induced reduction in mRNA level of hypoxia-inducible factor (HIF)-1α was significantly recovered by vanillin. In addition, the antagonizing effect of vanillin on UVA was found to be mediated by reduced production of PGE2 through inhibiting JNK and p38 MAPK. Taken together, these findings showed that vanillin could improve the reduced stemness of hAMSCs induced by UVA. The effect of vanillin is mediated by upregulating HIF-1α via inhibiting PGE2-cAMP signaling. Therefore, vanillin might be used as an antagonizing agent to mitigate the effects of UVA.

  3. FOXC1 maintains the hair follicle stem cell niche and governs stem cell quiescence to preserve long-term tissue-regenerating potential.

    PubMed

    Lay, Kenneth; Kume, Tsutomu; Fuchs, Elaine

    2016-03-15

    Adult tissue stem cells (SCs) reside in niches, which orchestrate SC behavior. SCs are typically used sparingly and exist in quiescence unless activated for tissue growth. Whether parsimonious SC use is essential to conserve long-term tissue-regenerating potential during normal homeostasis remains poorly understood. Here, we examine this issue by conditionally ablating a key transcription factor Forkhead box C1 (FOXC1) expressed in hair follicle SCs (HFSCs). FOXC1-deficient HFSCs spend less time in quiescence, leading to markedly shortened resting periods between hair cycles. The enhanced hair cycling accelerates HFSC expenditure, and impacts hair regeneration in aging mice. Interestingly, although FOXC1-deficient HFs can still form a new bulge that houses HFSCs for the next hair cycle, the older bulge is left unanchored. As the new hair emerges, the entire old bulge, including its reserve HFSCs and SC-inhibitory inner cell layer, is lost. We trace this mechanism first, to a marked increase in cell cycle-associated transcripts upon Foxc1 ablation, and second, to a downstream reduction in E-cadherin-mediated inter-SC adhesion. Finally, we show that when the old bulge is lost with each hair cycle, overall levels of SC-inhibitory factors are reduced, further lowering the threshold for HFSC activity. Taken together, our findings suggest that HFSCs have restricted potential in vivo, which they conserve by coupling quiescence to adhesion-mediated niche maintenance, thereby achieving long-term tissue homeostasis.

  4. FOXC1 maintains the hair follicle stem cell niche and governs stem cell quiescence to preserve long-term tissue-regenerating potential

    PubMed Central

    Lay, Kenneth; Kume, Tsutomu; Fuchs, Elaine

    2016-01-01

    Adult tissue stem cells (SCs) reside in niches, which orchestrate SC behavior. SCs are typically used sparingly and exist in quiescence unless activated for tissue growth. Whether parsimonious SC use is essential to conserve long-term tissue-regenerating potential during normal homeostasis remains poorly understood. Here, we examine this issue by conditionally ablating a key transcription factor Forkhead box C1 (FOXC1) expressed in hair follicle SCs (HFSCs). FOXC1-deficient HFSCs spend less time in quiescence, leading to markedly shortened resting periods between hair cycles. The enhanced hair cycling accelerates HFSC expenditure, and impacts hair regeneration in aging mice. Interestingly, although FOXC1-deficient HFs can still form a new bulge that houses HFSCs for the next hair cycle, the older bulge is left unanchored. As the new hair emerges, the entire old bulge, including its reserve HFSCs and SC-inhibitory inner cell layer, is lost. We trace this mechanism first, to a marked increase in cell cycle-associated transcripts upon Foxc1 ablation, and second, to a downstream reduction in E-cadherin–mediated inter-SC adhesion. Finally, we show that when the old bulge is lost with each hair cycle, overall levels of SC-inhibitory factors are reduced, further lowering the threshold for HFSC activity. Taken together, our findings suggest that HFSCs have restricted potential in vivo, which they conserve by coupling quiescence to adhesion-mediated niche maintenance, thereby achieving long-term tissue homeostasis. PMID:26912458

  5. Formation of electric dipoles in pea stem tissue due to an electric field

    NASA Astrophysics Data System (ADS)

    Ahmadi, Fatemeh; Farahani, Elham

    2016-07-01

    For examining the effect of an electrical field (DC) on pea seed, we exposed the pea seeds to electric fields with intensities 1, 4 and 7 kV/cm for 30, 230, 430 and 630 seconds. The tests were repeated three times, and each iteration had 5 seeds. Then, the seeds were moved to packaged plates. Finally, microscopic observation of the pea stem tissue showed that the application of a DC electrical field caused a deformation in the pea stem tissue. The results led us to examine the deformation of the tissue theoretically and to address that deformation as an electrostatic problem. In this regard, we modeled the pea stem based on the formation of electric dipoles. Then, theoretically, we calculated the force acting on each xylem section by coding, and the results were consistent with the experimental data.

  6. The potential for resident lung mesenchymal stem cells to promote functional tissue regeneration: understanding microenvironmental cues.

    PubMed

    Foronjy, Robert F; Majka, Susan M

    2012-12-01

    Tissue resident mesenchymal stem cells (MSCs) are important regulators of tissue repair or regeneration, fibrosis, inflammation, angiogenesis and tumor formation. Bone marrow derived mesenchymal stem cells (BM-MSCs) and endothelial progenitor cells (EPC) are currently being considered and tested in clinical trials as a potential therapy in patients with such inflammatory lung diseases including, but not limited to, chronic lung disease, pulmonary arterial hypertension (PAH), pulmonary fibrosis (PF), chronic obstructive pulmonary disease (COPD)/emphysema and asthma. However, our current understanding of tissue resident lung MSCs remains limited. This review addresses how environmental cues impact on the phenotype and function of this endogenous stem cell pool. In addition, it examines how these local factors influence the efficacy of cell-based treatments for lung diseases.

  7. "The state of the heart": Recent advances in engineering human cardiac tissue from pluripotent stem cells.

    PubMed

    Sirabella, Dario; Cimetta, Elisa; Vunjak-Novakovic, Gordana

    2015-08-01

    The pressing need for effective cell therapy for the heart has led to the investigation of suitable cell sources for tissue replacement. In recent years, human pluripotent stem cell research expanded tremendously, in particular since the derivation of human-induced pluripotent stem cells. In parallel, bioengineering technologies have led to novel approaches for in vitro cell culture. The combination of these two fields holds potential for in vitro generation of high-fidelity heart tissue, both for basic research and for therapeutic applications. However, this new multidisciplinary science is still at an early stage. Many questions need to be answered and improvements need to be made before clinical applications become a reality. Here we discuss the current status of human stem cell differentiation into cardiomyocytes and the combined use of bioengineering approaches for cardiac tissue formation and maturation in developmental studies, disease modeling, drug testing, and regenerative medicine.

  8. Advanced imaging and tissue engineering of the human limbal epithelial stem cell niche.

    PubMed

    Massie, Isobel; Dziasko, Marc; Kureshi, Alvena; Levis, Hannah J; Morgan, Louise; Neale, Michael; Sheth, Radhika; Tovell, Victoria E; Vernon, Amanda J; Funderburgh, James L; Daniels, Julie T

    2015-01-01

    The limbal epithelial stem cell niche provides a unique, physically protective environment in which limbal epithelial stem cells reside in close proximity with accessory cell types and their secreted factors. The use of advanced imaging techniques is described to visualize the niche in three dimensions in native human corneal tissue. In addition, a protocol is provided for the isolation and culture of three different cell types, including human limbal epithelial stem cells from the limbal niche of human donor tissue. Finally, the process of incorporating these cells within plastic compressed collagen constructs to form a tissue-engineered corneal limbus is described and how immunohistochemical techniques may be applied to characterize cell phenotype therein.

  9. Advanced Imaging and Tissue Engineering of the Human Limbal Epithelial Stem Cell Niche

    PubMed Central

    Massie, Isobel; Dziasko, Marc; Kureshi, Alvena; Levis, Hannah J.; Morgan, Louise; Neale, Michael; Sheth, Radhika; Tovell, Victoria E.; Vernon, Amanda J.; Funderburgh, James L.; Daniels, Julie T.

    2015-01-01

    The limbal epithelial stem cell niche provides a unique, physically protective environment in which limbal epithelial stem cells reside in close proximity with accessory cell types and their secreted factors. The use of advanced imaging techniques is described to visualize the niche in three dimensions in native human corneal tissue. In addition, a protocol is provided for the isolation and culture of three different cell types, including human limbal epithelial stem cells from the limbal niche of human donor tissue. Finally, the process of incorporating these cells within plastic compressed collagen constructs to form a tissue-engineered corneal limbus is described and how immunohistochemical techniques may be applied to characterize cell phenotype therein. PMID:25388395

  10. Experimental therapies for repair of the central nervous system: stem cells and tissue engineering.

    PubMed

    Forraz, N; Wright, K E; Jurga, M; McGuckin, C P

    2013-07-01

    Several stem cell-based therapeutic tools are currently being investigated for the regeneration of central nervous system (CNS) injuries. This review focuses on innovative approaches for CNS tissue repair via the use of implantable cellular devices. These devices are supported by biopharmaceuticals and conventional physiotherapy for the restoration of lost neuronal circuits and CNS function. This paper further reviews new and promising tools currently in pre-clinical and clinical tests for the treatment of CNS diseases where substantial loss of cellular and extracellular components of neural tissue has occurred such as stroke, encephalopathy and traumatic neural injuries. We also discuss selected 3D bioscaffolds co-cultured with clinically applicable human mesenchymal stem cells. Recent advances in neural tissue engineering and stem cell differentiation methods have shown promise for their clinical application in treating yet incurable CNS deficits.

  11. Mesenchymal stem cells from the oral cavity and their potential value in tissue engineering.

    PubMed

    Sanz, Antonio R; Carrión, Flavio S; Chaparro, Alejandra P

    2015-02-01

    Periodontal disease is one of the most common conditions affecting humans, and current treatment strategies, which focus on the removal and long-term control of dental plaque, are generally successful in eliminating active disease and promoting tissue repair. However, regeneration of the supporting structures of the tooth remains an elusive goal and a challenge. The formation of new bone and cementum with supportive periodontal ligament is the ultimate objective, but current regeneration therapies are incapable of achieving this in a predictable way. The regeneration of periodontal tissue requires a combination of fundamental events, such as appropriate level and sequencing of regulatory signals, the presence of progenitor cells, an extracellular matrix or carrier and an adequate blood supply. Based on tissue-engineering concepts, the regeneration process may be modulated by manipulating the signaling pathways of regulatory molecules, the extracellular matrix or scaffold, or the cellular components. The identification of mesenchymal stem cells from bone marrow started a new era in regenerative medicine. Tissue engineering using mesenchymal stem cells became a therapeutic option with several advantages, including high-quality regeneration of damaged tissues without the formation of fibrous tissue, minimal donor-site morbidity compared with autografts and a low risk of autoimmune rejection and disease transmission. The aim of this review was to describe the main sources of mesenchymal stem cells from tissues in the oral cavity and the potential of these cells in regenerative therapy. Special attention is paid to gingival tissue-derived mesenchymal stem cells because they represent the most accessible source of stem cells in the human mouth.

  12. Generation of embryonic stem cells from mouse adipose-tissue derived cells via somatic cell nuclear transfer

    PubMed Central

    Qin, Yiren; Qin, Jilong; Zhou, Chikai; Li, Jinsong; Gao, Wei-Qiang

    2015-01-01

    Somatic cells can be reprogrammed into embryonic stem cells (ESCs) by nuclear transfer (NT-ESCs), or into induced pluripotent stem cells (iPSCs) by the “Yamanaka method.” However, recent studies have indicated that mouse and human iPSCs are prone to epigenetic and transcriptional aberrations, and that NT-ESCs correspond more closely to ESCs derived from in vitro fertilized embryos than iPSCs. In addition, the procedure of NT-ESCs does not involve gene modification. Demonstration of generation of NT-ESCs using an easily-accessible source of adult cell types would be very important. Adipose tissue is a source of readily accessible donor cells and can be isolated from both males and females at different ages. Here we report that NT-ESCs can be generated from adipose tissue-derived cells (ADCs). At morphological, mRNA and protein levels, these NT-ESCs show classic ESC colonies, exhibit alkaline phosphatase (AP) activity, and display normal diploid karyotypes. Importantly, these cells express pluripotent markers including Oct4, Sox2, Nanog and SSEA-1. Furthermore, they can differentiate in vivo into various types of cells from 3 germinal layers by teratoma formation assays. This study demonstrates for the first time that ESCs can be generated from the adipose tissue by somatic cell nuclear transfer (SCNT) and suggests that ADCs can be a new donor-cell type for potential therapeutic cloning. PMID:25692793

  13. Generation of embryonic stem cells from mouse adipose-tissue derived cells via somatic cell nuclear transfer.

    PubMed

    Qin, Yiren; Qin, Jilong; Zhou, Chikai; Li, Jinsong; Gao, Wei-Qiang

    2015-01-01

    Somatic cells can be reprogrammed into embryonic stem cells (ESCs) by nuclear transfer (NT-ESCs), or into induced pluripotent stem cells (iPSCs) by the "Yamanaka method." However, recent studies have indicated that mouse and human iPSCs are prone to epigenetic and transcriptional aberrations, and that NT-ESCs correspond more closely to ESCs derived from in vitro fertilized embryos than iPSCs. In addition, the procedure of NT-ESCs does not involve gene modification. Demonstration of generation of NT-ESCs using an easily-accessible source of adult cell types would be very important. Adipose tissue is a source of readily accessible donor cells and can be isolated from both males and females at different ages. Here we report that NT-ESCs can be generated from adipose tissue-derived cells (ADCs). At morphological, mRNA and protein levels, these NT-ESCs show classic ESC colonies, exhibit alkaline phosphatase (AP) activity, and display normal diploid karyotypes. Importantly, these cells express pluripotent markers including Oct4, Sox2, Nanog and SSEA-1. Furthermore, they can differentiate in vivo into various types of cells from 3 germinal layers by teratoma formation assays. This study demonstrates for the first time that ESCs can be generated from the adipose tissue by somatic cell nuclear transfer (SCNT) and suggests that ADCs can be a new donor-cell type for potential therapeutic cloning.

  14. Recent insights into the molecular mechanisms involved in aging and the malignant transformation of adult stem/progenitor cells and their therapeutic implications

    PubMed Central

    Mimeault, Murielle; Batra, Surinder K.

    2013-01-01

    Recent advancements in tissue-resident adult stem/progenitor cell research have revealed that enhanced telomere attrition, oxidative stress, ultraviolet radiation exposure and oncogenic events leading to severe DNA damages and genomic instability may occur in these immature and regenerative cells during chronological aging. Particularly, the alterations in key signaling components controlling their self-renewal capacity and an up-regulation of tumor suppressor gene products such as p16INK4A, p19ARF, ataxia-telangiectasia mutated (ATM) kinase, p53and/or theforkhead box O (FOXOs) family of transcription factors may result in their dysfunctions, growth arrest and senescence or apoptotic death during the aging process. These molecular events may culminate in a progressive decline in the regenerative functions and the number of tissue-resident adult stem/progenitor cells, and age-related disease development. Conversely, the telomerase re-activation and accumulation of numerous genetic and/or epigenetic alterations in adult stem/progenitor cells with advancing age may result in their immortalization and malignant transformation into highly leukemic or tumorigenic cancer-initiating cells and cancer initiation. Therefore, the cell-replacement and gene therapies and molecular targeting of aged and dysfunctional adult stem/progenitor cells including their malignant counterpart, cancer-initiating cells, hold great promise for treating and even curing diverse devastating human diseases. These diseases include premature aging diseases, hematopoietic, cardiovascular, musculoskeletal, pulmonary, ocular, urogenital, neurodegenerative and skin disorders and aggressive and recurrent cancers. PMID:19114129

  15. Human embryonic and fetal mesenchymal stem cells differentiate toward three different cardiac lineages in contrast to their adult counterparts.

    PubMed

    Ramkisoensing, Arti A; Pijnappels, Daniël A; Askar, Saïd F A; Passier, Robert; Swildens, Jim; Goumans, Marie José; Schutte, Cindy I; de Vries, Antoine A F; Scherjon, Sicco; Mummery, Christine L; Schalij, Martin J; Atsma, Douwe E

    2011-01-01

    Mesenchymal stem cells (MSCs) show unexplained differences in differentiation potential. In this study, differentiation of human (h) MSCs derived from embryonic, fetal and adult sources toward cardiomyocytes, endothelial and smooth muscle cells was investigated. Labeled hMSCs derived from embryonic stem cells (hESC-MSCs), fetal umbilical cord, bone marrow, amniotic membrane and adult bone marrow and adipose tissue were co-cultured with neonatal rat cardiomyocytes (nrCMCs) or cardiac fibroblasts (nrCFBs) for 10 days, and also cultured under angiogenic conditions. Cardiomyogenesis was assessed by human-specific immunocytological analysis, whole-cell current-clamp recordings, human-specific qRT-PCR and optical mapping. After co-culture with nrCMCs, significantly more hESC-MSCs than fetal hMSCs stained positive for α-actinin, whereas adult hMSCs stained negative. Furthermore, functional cardiomyogenic differentiation, based on action potential recordings, was shown to occur, but not in adult hMSCs. Of all sources, hESC-MSCs expressed most cardiac-specific genes. hESC-MSCs and fetal hMSCs contained significantly higher basal levels of connexin43 than adult hMSCs and co-culture with nrCMCs increased expression. After co-culture with nrCFBs, hESC-MSCs and fetal hMSCs did not express α-actinin and connexin43 expression was decreased. Conduction velocity (CV) in co-cultures of nrCMCs and hESC-MSCs was significantly higher than in co-cultures with fetal or adult hMSCs. In angiogenesis bioassays, only hESC-MSCs and fetal hMSCs were able to form capillary-like structures, which stained for smooth muscle and endothelial cell markers.Human embryonic and fetal MSCs differentiate toward three different cardiac lineages, in contrast to adult MSCs. Cardiomyogenesis is determined by stimuli from the cellular microenvironment, where connexin43 may play an important role.

  16. Mesenchymal Stem Cells from Adipose Tissue in Clinical Applications for Dermatological Indications and Skin Aging

    PubMed Central

    Gaur, Meenakshi; Dobke, Marek; Lunyak, Victoria V.

    2017-01-01

    Operating at multiple levels of control, mesenchymal stem cells from adipose tissue (ADSCs) communicate with organ systems to adjust immune response, provide signals for differentiation, migration, enzymatic reactions, and to equilibrate the regenerative demands of balanced tissue homeostasis. The identification of the mechanisms by which ADSCs accomplish these functions for dermatological rejuvenation and wound healing has great potential to identify novel targets for the treatment of disorders and combat aging. Herein, we review new insights into the role of adipose-derived stem cells in the maintenance of dermal and epidermal homeostasis, and recent advances in clinical applications of ADSCs related to dermatology. PMID:28117680

  17. Mesenchymal Stem Cells from Adipose Tissue in Clinical Applications for Dermatological Indications and Skin Aging.

    PubMed

    Gaur, Meenakshi; Dobke, Marek; Lunyak, Victoria V

    2017-01-20

    Operating at multiple levels of control, mesenchymal stem cells from adipose tissue (ADSCs) communicate with organ systems to adjust immune response, provide signals for differentiation, migration, enzymatic reactions, and to equilibrate the regenerative demands of balanced tissue homeostasis. The identification of the mechanisms by which ADSCs accomplish these functions for dermatological rejuvenation and wound healing has great potential to identify novel targets for the treatment of disorders and combat aging. Herein, we review new insights into the role of adipose-derived stem cells in the maintenance of dermal and epidermal homeostasis, and recent advances in clinical applications of ADSCs related to dermatology.

  18. ADULT NEURAL STEM CELLS: RESPONSE TO STROKE INJURY AND POTENTIAL FOR THERAPEUTIC APPLICATIONS

    PubMed Central

    Barkho, Basam Z.; Zhao, Xinyu

    2011-01-01

    The plasticity of neural stem/progenitor cells allows a variety of different responses to many environmental cues. In the past decade, significant research has gone into understanding the regulation of neural stem/progenitor cell properties, because of their promise for cell replacement therapies in adult neurological diseases. Both endogenous and grafted neural stem/progenitor cells are known to have the ability to migrate long distances to lesioned sites after brain injury and differentiate into new neurons. Several chemokines and growth factors, including stromal cell-derived factor-1 and vascular endothelial growth factor, have been shown to stimulate the proliferation, differentiation, and migration of neural stem/progenitor cells, and investigators have now begun to identify the critical downstream effectors and signaling mechanisms that regulate these processes. Both our own lab and others have shown that the extracellular matrix and matrix remodeling factors play a critical role in directing cell differentiation and migration of adult neural stem/progenitor cells within injured sites. Identification of these and other molecular pathways involved in stem cell homing into ischemic areas is vital for the development of new treatments. To ensure the best functional recovery, regenerative therapy may require the application of a combination approach that includes cell replacement, trophic support, and neural protection. Here we review the current state of our knowledge about endogenous adult and exogenous neural stem/progenitor cells as potential therapeutic agents for central nervous system injuries. PMID:21466483

  19. Application of stem cells derived from the periodontal ligament or gingival tissue sources for tendon tissue regeneration.

    PubMed

    Moshaverinia, Alireza; Xu, Xingtian; Chen, Chider; Ansari, Sahar; Zadeh, Homayoun H; Snead, Malcolm L; Shi, Songtao

    2014-03-01

    Tendon injuries are often associated with significant dysfunction and disability due to tendinous tissue's very limited self-repair capacity and propensity for scar formation. Dental-derived mesenchymal stem cells (MSCs) in combination with appropriate scaffold material present an alternative therapeutic option for tendon repair/regeneration that may be advantageous compared to other current treatment modalities. The MSC delivery vehicle is the principal determinant for successful implementation of MSC-mediated regenerative therapies. In the current study, a co-delivery system based on TGF-β3-loaded RGD-coupled alginate microspheres was developed for encapsulating periodontal ligament stem cells (PDLSCs) or gingival mesenchymal stem cells (GMSCs). The capacity of encapsulated dental MSCs to differentiate into tendon tissue was investigated in vitro and in vivo. Encapsulated dental-derived MSCs were transplanted subcutaneously into immunocompromised mice. Our results revealed that after 4 weeks of differentiation in vitro, PDLSCs and GMSCs as well as the positive control human bone marrow mesenchymal stem cells (hBMMSCs) exhibited high levels of mRNA expression for gene markers related to tendon regeneration (Scx, DCn, Tnmd, and Bgy) via qPCR measurement. In a corresponding in vivo animal model, ectopic neo-tendon regeneration was observed in subcutaneous transplanted MSC-alginate constructs, as confirmed by histological and immunohistochemical staining for protein markers specific for tendons. Interestingly, in our quantitative PCR and in vivo histomorphometric analyses, PDLSCs showed significantly greater capacity for tendon regeneration than GMSCs or hBMMSCs (P < 0.05). Altogether, these findings indicate that periodontal ligament and gingival tissues can be considered as suitable stem cell sources for tendon engineering. PDLSCs and GMSCs encapsulated in TGF-β3-loaded RGD-modified alginate microspheres are promising candidates for tendon regeneration.

  20. Organ and tissue donation: a survey of nurse's knowledge and educational needs in an adult ITU.

    PubMed

    Collins, Timothy J

    2005-08-01

    The aim of this paper is to present the results of a survey that was undertaken to assess nurses' knowledge and educational needs towards organ donation within one adult general intensive care unit. The survey consists of 31 registered nurses who completed a confidential questionnaire that aimed to assess their existing knowledge and deficits in organ and tissue donation. The survey highlights the sample lacked confidence in approaching relatives for donation consent, deficits in brain stem death testing and donor criteria. It was also apparent that a significant number of nurses could not identify which tissues can be donated and the contraindications for tissue donation. A majority of the sample stated their knowledge of donation issues would improve if an educational programme were developed on organ donation. This is further supported by previous work by [Bidigare S, Oermann M, 1991. Attitudes and knowledge of nurses regarding organ procurement. Heart & lung 1:20-3; Smith-Brew S, Yanai L, 1996. The organ donation process through a review of the literature. Part 1. Accident & emergency nursing 4:5-11; Roark D, 2000. Overhauling the organ donation system. Am J Nurs 6:44-9] who suggest that educational programmes covering donation issues should enhance nurses' knowledge and confidence in the organ donation process and ultimately increase the number of potential donors.

  1. Human oocytes reprogram adult somatic nuclei of a type 1 diabetic to diploid pluripotent stem cells.

    PubMed

    Yamada, Mitsutoshi; Johannesson, Bjarki; Sagi, Ido; Burnett, Lisa Cole; Kort, Daniel H; Prosser, Robert W; Paull, Daniel; Nestor, Michael W; Freeby, Matthew; Greenberg, Ellen; Goland, Robin S; Leibel, Rudolph L; Solomon, Susan L; Benvenisty, Nissim; Sauer, Mark V; Egli, Dieter

    2014-06-26

    The transfer of somatic cell nuclei into oocytes can give rise to pluripotent stem cells that are consistently equivalent to embryonic stem cells, holding promise for autologous cell replacement therapy. Although methods to induce pluripotent stem cells from somatic cells by transcription factors are widely used in basic research, numerous differences between induced pluripotent stem cells and embryonic stem cells have been reported, potentially affecting their clinical use. Because of the therapeutic potential of diploid embryonic stem-cell lines derived from adult cells of diseased human subjects, we have systematically investigated the parameters affecting efficiency of blastocyst development and stem-cell derivation. Here we show that improvements to the oocyte activation protocol, including the use of both kinase and translation inhibitors, and cell culture in the presence of histone deacetylase inhibitors, promote development to the blastocyst stage. Developmental efficiency varied between oocyte donors, and was inversely related to the number of days of hormonal stimulation required for oocyte maturation, whereas the daily dose of gonadotropin or the total number of metaphase II oocytes retrieved did not affect developmental outcome. Because the use of concentrated Sendai virus for cell fusion induced an increase in intracellular calcium concentration, causing premature oocyte activation, we used diluted Sendai virus in calcium-free medium. Using this modified nuclear transfer protocol, we derived diploid pluripotent stem-cell lines from somatic cells of a newborn and, for the first time, an adult, a female with type 1 diabetes.

  2. A planarian p53 homolog regulates proliferation and self-renewal in adult stem cell lineages.

    PubMed

    Pearson, Bret J; Sánchez Alvarado, Alejandro

    2010-01-01

    The functions of adult stem cells and tumor suppressor genes are known to intersect. However, when and how tumor suppressors function in the lineages produced by adult stem cells is unknown. With a large population of stem cells that can be manipulated and studied in vivo, the freshwater planarian is an ideal system with which to investigate these questions. Here, we focus on the tumor suppressor p53, homologs of which have no known role in stem cell biology in any invertebrate examined thus far. Planaria have a single p53 family member, Smed-p53, which is predominantly expressed in newly made stem cell progeny. When Smed-p53 is targeted by RNAi, the stem cell population increases at the expense of progeny, resulting in hyper-proliferation. However, ultimately the stem cell population fails to self-renew. Our results suggest that prior to the vertebrates, an ancestral p53-like molecule already had functions in stem cell proliferation control and self-renewal.

  3. Diversity of Epithelial Stem Cell Types in Adult Lung

    PubMed Central

    Li, Feng; He, Jinxi; Wei, Jun; Cho, William C.; Liu, Xiaoming

    2015-01-01

    Lung is a complex organ lined with epithelial cells. In order to maintain its homeostasis and normal functions following injuries caused by varied extraneous and intraneous insults, such as inhaled environmental pollutants and overwhelming inflammatory responses, the respiratory epithelium normally undergoes regenerations by the proliferation and differentiation of region-specific epithelial stem/progenitor cells that resided in distinct niches along the airway tree. The importance of local epithelial stem cell niches in the specification of lung stem/progenitor cells has been recently identified. Studies using cell differentiating and lineage tracing assays, in vitro and/or ex vivo models, and genetically engineered mice have suggested that these local epithelial stem/progenitor cells within spatially distinct regions along the pulmonary tree contribute to the injury repair of epithelium adjacent to their respective niches. This paper reviews recent findings in the identification and isolation of region-specific epithelial stem/progenitor cells and local niches along the airway tree and the potential link of epithelial stem cells for the development of lung cancer. PMID:25810726

  4. Tooth Tissue Engineering: The Importance of Blood Products as a Supplement in Tissue Culture Medium for Human Pulp Dental Stem Cells.

    PubMed

    Pisciolaro, Ricardo Luiz; Duailibi, Monica Talarico; Novo, Neil Ferreira; Juliano, Yara; Pallos, Debora; Yelick, Pamela Crotty; Vacanti, Joseph Phillip; Ferreira, Lydia Masako; Duailibi, Silvio Eduardo

    2015-11-01

    One of the goals in using cells for tissue engineering (TE) and cell therapy consists of optimizing the medium for cell culture. The present study compares three different blood product supplements for improved cell proliferation and protection against DNA damage in cultured human dental pulp stem cells for tooth TE applications. Human cells from dental pulp were first characterized as adult stem cells (ectomesenchymal mixed origin) by flow cytometry. Next, four different cell culture conditions were tested: I, supplement-free; II, supplemented with fetal bovine serum; III, allogeneic human serum; and IV, autologous human serum. Cultured cells were then characterized for cell proliferation, mineralized nodule formation, and colony-forming units (CFU) capability. After 28 days in culture, the comet assay was performed to assess possible damage in cellular DNA. Our results revealed that Protocol IV achieved higher cell proliferation than Protocol I (p = 0.0112). Protocols II and III resulted in higher cell proliferation than Protocol I, but no statistical differences were found relative to Protocol IV. The comet assay revealed less cell damage in cells cultured using Protocol IV as compared to Protocols II and III. The damage percentage observed on Protocol II was significantly higher than all other protocols. CFUs capability was highest using Protocol IV (p = 0.0018) and III, respectively, and the highest degree of mineralization was observed using Protocol IV as compared to Protocols II and III. Protocol IV resulted in significantly improved cell proliferation, and no cell damage was observed. These results demonstrate that human blood product supplements can be used as feasible supplements for culturing adult human dental stem cells.

  5. Tissue engineering, stem cells, cloning, and parthenogenesis: new paradigms for therapy

    PubMed Central

    Hipp, Jason; Atala, Anthony

    2004-01-01

    Patients suffering from diseased and injured organs may be treated with transplanted organs. However, there is a severe shortage of donor organs which is worsening yearly due to the aging population. Scientists in the field of tissue engineering apply the principles of cell transplantation, materials science, and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Both therapeutic cloning (nucleus from a donor cell is transferred into an enucleated oocyte), and parthenogenesis (oocyte is activated and stimulated to divide), permit extraction of pluripotent embryonic stem cells, and offer a potentially limitless source of cells for tissue engineering applications. The stem cell field is also advancing rapidly, opening new options for therapy. The present article reviews recent progress in tissue engineering and describes applications of these new technologies that may offer novel therapies for patients with end-stage organ failure. PMID:15588286

  6. Typography manipulations can affect priming of word stem completion in older and younger adults.

    PubMed

    Gibson, J M; Brooks, J O; Friedman, L; Yesavage, J A

    1993-12-01

    The experiments reported here investigated whether changes of typography affected priming of word stem completion performance in older and younger adults. Across all experiments, the typeface in which a word appeared at presentation either did or did not match that of its 3-letter stem at test. In Experiment 1, no significant evidence of a typography effect was found when words were presented with a sentence judgment or letter judgment task. However, subsequent experiments revealed that, in both older and younger adults, only words presented with a syllable judgment task gave rise to the typography effect (Experiments 2-4). Specifically, performance was greater, when the presentation and test typeface matched than when they did not. Experiment 5, which used stem-cued recall, did not reveal a difference between syllable and letter judgment tasks. These findings highlight the complex nature of word stem completion performance.

  7. Ebselen Preserves Tissue-Engineered Cell Sheets and their Stem Cells in Hypothermic Conditions

    PubMed Central

    Katori, Ryosuke; Hayashi, Ryuhei; Kobayashi, Yuki; Kobayashi, Eiji; Nishida, Kohji

    2016-01-01

    Clinical trials have been performed using autologous tissue-engineered epithelial cell sheets for corneal regenerative medicine. To improve stem cell-based therapy for convenient clinical practice, new techniques are required for preserving reconstructed tissues and their stem/progenitor cells until they are ready for use. In the present study, we screened potential preservative agents and developed a novel medium for preserving the cell sheets and their stem/progenitor cells; the effects were evaluated with a luciferase-based viability assay. Nrf2 activators, specifically ebselen, could maintain high ATP levels during preservation. Ebselen also showed a strong influence on maintenance of the viability, morphology, and stem cell function of the cell sheets preserved under hypothermia by protecting them from reactive oxygen species-induced damage. Furthermore, ebselen drastically improved the preservation performance of human cornea tissues and their stem cells. Therefore, ebselen shows good potential as a useful preservation agent in regenerative medicine as well as in cornea transplantation. PMID:27966584

  8. Bonghan system as mesenchymal stem cell niches and pathways of macrophages in adipose tissues.

    PubMed

    Lee, Byung-Cheon; Bae, Kyung-Hee; Jhon, Gil-Ja; Soh, Kwang-Sup

    2009-03-01

    A new technique for visualizing Bonghan ducts (BHDs) and Bonghan corpuscles (BHCs) was developed by using a vivi-staining dye, Trypan blue. The dye stains BHDs and BHCs preferentially to adipocytes so that tracking a BHD and a BHC, even inside adipose tissues, is possible. Concerning the functions of the BHD and the BHC in adipose tissues, we propose conjectures: the Bonghan system may be niches for mesenchymal stem cells, which can differentiate into adipocytes, and pathways for macrophages involved in adipogenesis.

  9. [Advance of researches on thyroid tissues autotransplantation and embryonic stem cell transplantation in therapy of hypothyroidism].

    PubMed

    Ma, Quanfu; Kuang, Anren

    2008-10-01

    Patients with irreversible hypothyroidism require lifelong levo-thyroxin ( L-T4) replacement therapy, which makes them feel discomfortable. With the development of the thyroid tissues autotransplantation and embryonic stem cell (ESC), this would be a more physiological approach to the treatment of irreversible hypothyroidism. The animal experiments and human clinical trials on thyroid tissues autotransplantation have shown that the autograft can survive and function. The advanced researches have demonstrated that ESC can differentiate into thyroid follicular cells.

  10. Immediate differentiation of neuronal cells from stem/progenitor-like cells in the avian iris tissues.

    PubMed

    Matsushita, Tamami; Fujihara, Ai; Royall, Lars; Kagiwada, Satoshi; Kosaka, Mitsuko; Araki, Masasuke

    2014-06-01

    A simple culture method that was recently developed in our laboratory was applied to the chick iris tissues to characterize neural stem/progenitor-like cells. Iris tissue is a non-neuronal tissue and does not contain any neuronal cells. In the present study we isolated iris tissues from chick embryos just prior to hatching. The isolated iris pigmented epithelium (IPE) or the stroma was embedded in Matrigel and cultured in Dulbecco's MEM supplemented with either fetal bovine serum or the synthetic serum replacement solution B27. Within 24 h of culture, elongated cells with long processes extended out from the explants of both tissues and were positively stained for various neuronal markers such as transitin, Tuj-1 and acetylated tubulin. After a longer culture period, cells positive for photoreceptor markers like rhodopsin, iodopsin and visinin were found, suggesting that the iris tissues contain retinal stem/progenitor-like cells. Several growth factors were examined to determine their effects on neuronal differentiation. EGF was shown to dramatically enhance neuronal cell differentiation, particularly the elongation of neuronal fibers. The addition of exogenous FGF2, however, did not show any positive effects on neuronal differentiation, although FGF signaling inhibitor, SU5402, suppressed neuronal differentiation. The results show that neuronal stem/progenitor-like cells can differentiate into neuronal cells immediately after they are transferred into an appropriate environment. This process did not require any exogenous factors, suggesting that neural stem/progenitor-like cells are simply suppressed from neuronal differentiation within the tissue, and isolation from the tissue releases the cells from the suppression mechanism.

  11. Planarian yorkie/YAP functions to integrate adult stem cell proliferation, organ homeostasis and maintenance of axial patterning.

    PubMed

    Lin, Alexander Y T; Pearson, Bret J

    2014-03-01

    During adult homeostasis and regeneration, the freshwater planarian must accomplish a constant balance between cell proliferation and cell death, while also maintaining proper tissue and organ size and patterning. How these ordered processes are precisely modulated remains relatively unknown. Here we show that planarians use the downstream effector of the Hippo signaling cascade, yorkie (yki; YAP in vertebrates) to control a diverse set of pleiotropic processes in organ homeostasis, stem cell regulation, regeneration and axial patterning. We show that yki functions to maintain the homeostasis of the planarian excretory (protonephridial) system and to limit stem cell proliferation, but does not affect the differentiation process or cell death. Finally, we show that Yki acts synergistically with WNT/β-catenin signaling to repress head determination by limiting the expression domains of posterior WNT genes and that of the WNT-inhibitor notum. Together, our data show that yki is a key gene in planarians that integrates stem cell proliferation control, organ homeostasis, and the spatial patterning of tissues.

  12. Type 3 innate lymphoid cells maintain intestinal epithelial stem cells after tissue damage.

    PubMed

    Aparicio-Domingo, Patricia; Romera-Hernandez, Monica; Karrich, Julien J; Cornelissen, Ferry; Papazian, Natalie; Lindenbergh-Kortleve, Dicky J; Butler, James A; Boon, Louis; Coles, Mark C; Samsom, Janneke N; Cupedo, Tom

    2015-10-19

    Disruption of the intestinal epithelial barrier allows bacterial translocation and predisposes to destructive inflammation. To ensure proper barrier composition, crypt-residing stem cells continuously proliferate and replenish all intestinal epithelial cells within days. As a consequence of this high mitotic activity, mucosal surfaces are frequently targeted by anticancer therapies, leading to dose-limiting side effects. The cellular mechanisms that control tissue protection and mucosal healing in response to intestinal damage remain poorly understood. Type 3 innate lymphoid cells (ILC3s) are regulators of homeostasis and tissue responses to infection at mucosal surfaces. We now demonstrate that ILC3s are required for epithelial activation and proliferation in response to small intestinal tissue damage induced by the chemotherapeutic agent methotrexate. Multiple subsets of ILC3s are activated after intestinal tissue damage, and in the absence of ILC3s, epithelial activation is lost, correlating with increased pathology and severe damage to the intestinal crypts. Using ILC3-deficient Lgr5 reporter mice, we show that maintenance of intestinal stem cells after damage is severely impaired in the absence of ILC3s or the ILC3 signature cytokine IL-22. These data unveil a novel function of ILC3s in limiting tissue damage by preserving tissue-specific stem cells.

  13. Using Stem Cells to Grow Artificial Tissue for Peripheral Nerve Repair

    PubMed Central

    Bhangra, Kulraj Singh; Busuttil, Francesca

    2016-01-01

    Peripheral nerve injury continues to pose a clinical hurdle despite its frequency and advances in treatment. Unlike the central nervous system, neurons of the peripheral nervous system have a greater ability to regenerate. However, due to a number of confounding factors, this is often both incomplete and inadequate. The lack of supportive Schwann cells or their inability to maintain a regenerative phenotype is a major factor. Advances in nervous system tissue engineering technology have led to efforts to build Schwann cell scaffolds to overcome this and enhance the regenerative capacity of neurons following injury. Stem cells that can differentiate along a neural lineage represent an essential resource and starting material for this process. In this review, we discuss the different stem cell types that are showing promise for nervous system tissue engineering in the context of peripheral nerve injury. We also discuss some of the biological, practical, ethical, and commercial considerations in using these different stem cells for future clinical application. PMID:27212954

  14. Assessment of stem cell carriers for tendon tissue engineering in pre-clinical models

    PubMed Central

    2014-01-01

    Tendon injuries are prevalent and problematic, especially among young and otherwise healthy individuals. The inherently slow innate healing process combined with the inevitable scar tissue formation compromise functional recovery, imposing the need for the development of therapeutic strategies. The limited number of low activity/reparative capacity tendon-resident cells has directed substantial research efforts towards the exploration of the therapeutic potential of various stem cells in tendon injuries and pathophysiologies. Severe injuries require the use of a stem cell carrier to enable cell localisation at the defect site. The present study describes advancements that injectable carriers, tissue grafts, anisotropically orientated biomaterials, and cell-sheets have achieved in preclinical models as stem cell carriers for tendon repair. PMID:25157898

  15. Application of stem cells derived from the periodontal ligament or gingival tissue sources for tendon tissue regeneration

    PubMed Central

    Moshaverinia, Alireza; Xu, Xingtian; Chen, Chider; Ansari, Sahar; Zadeh, Homayoun H.; Snead, Malcolm L.; Shi, Songtao

    2014-01-01

    Tendon injuries are often associated with significant dysfunction and disability due to tendinous tissue’s very limited self-repair capacity and propensity for scar formation. Dental-derived mesenchymal stem cells (MSCs) in combination with appropriate scaffold material present an alternative therapeutic option for tendon repair/regeneration that may be advantageous compared to other current treatment modalities. The MSC delivery vehicle is the principal determinant for successful implementation of MSC-mediated regenerative therapies. In the current study, a co-delivery system based on TGF-β3-loaded RGD-coupled alginate microspheres was developed for encapsulating periodontal ligament stem cells (PDLSCs) or gingival mesenchymal stem cells (GMSCs). The capacity of encapsulated dental MSCs to differentiate into tendon tissue was investigated in vitro and in vivo. Encapsulated dental-derived MSCs were transplanted subcutaneously into immunocompromised mice. Our results revealed that after 4 weeks of differentiation in vitro, PDLSCs and GMSCs as well as the positive control human bone marrow mesenchymal stem cells (hBMMSCs) exhibited high levels of mRNA expression for gene markers related to tendon regeneration (Scx, DCn, Tnmd, and Bgy) via qPCR measurement. In a corresponding in vivo animal model, ectopic neo-tendon regeneration was observed in subcutaneous transplanted MSC-alginate constructs, as confirmed by histological and immunohistochemical staining for protein markers specific for tendons. Interestingly, in our quantitative PCR and in vivo histomorphometric analyses, PDLSCs showed significantly greater capacity for tendon regeneration than GMSCs or hBMMSCs (P<0.05). Altogether, these findings indicate that periodontal ligament and gingival tissues can be considered as suitable stem cell sources for tendon engineering. PDLSCs and GMSCs encapsulated in TGF-β3-loaded RGD-modified alginate microspheres are promising candidates for tendon regeneration. PMID

  16. An essential and evolutionarily conserved role of protein arginine methyltransferase 1 for adult intestinal stem cells during postembryonic development.

    PubMed

    Matsuda, Hiroki; Shi, Yun-Bo

    2010-11-01

    Organ-specific adult stem cells are critical for the homeostasis of adult organs and organ repair and regeneration. Unfortunately, it has been difficult to investigate the origins of these stem cells and the mechanisms of their development, especially in mammals. Intestinal remodeling during frog metamorphosis offers a unique opportunity for such studies. During the transition from an herbivorous tadpole to a carnivorous frog, the intestine is completely remodeled as the larval epithelial cells undergo apoptotic degeneration and are replaced by adult epithelial cells developed de novo. The entire metamorphic process is under the control of thyroid hormone, making it possible to control the development of the adult intestinal stem cells. Here, we show that the thyroid hormone receptor-coactivator protein arginine methyltransferase 1 (PRMT1) is upregulated in a small number of larval epithelial cells and that these cells dedifferentiate to become the adult stem cells. More importantly, transgenic overexpression of PRMT1 leads to increased adult stem cells in the intestine, and conversely, knocking down the expression of endogenous PRMT1 reduces the adult stem cell population. In addition, PRMT1 expression pattern during zebrafish and mouse development suggests that PRMT1 may play an evolutionally conserved role in the development of adult intestinal stem cells throughout vertebrates. These findings are not only important for the understanding of organ-specific adult stem cell development but also have important implications in regenerative medicine of the digestive tract.

  17. [Use of mesenchymal stem cells for reparative processes activation in bone jaw tissue in experimental conditions].

    PubMed

    Volozhin, A I; Vasil'ev, A Iu; Malyginov, N N; Bulanova, I M; Grigor''ian, A S; Kiseleva, E V; Cherniaev, S E; Tarasenko, I V

    2010-01-01

    In experiment on 12 Chinchilla rabbits dynamics of reparative regeneration was studied at the terms 2 and 4 months. Bone defect in mandible corner was closed by osteoplastic material Gapkol which was covered from inside by allogenic or autologic stem cells received from rabbit adipose tissue. The results of the ray tracing methods of study were verified by SEM and histological methods.

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

    PubMed

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

    2012-09-01

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

  19. Biomimetic extracellular matrix mediated somatic stem cell differentiation: applications in dental pulp tissue regeneration

    PubMed Central

    Ravindran, Sriram; George, Anne

    2015-01-01

    Dental caries is one of the most widely prevalent infectious diseases in the world. It affects more than half of the world's population. The current treatment for necrotic dental pulp tissue arising from dental caries is root canal therapy. This treatment results in loss of tooth sensitivity and vitality making it prone for secondary infections. Over the past decade, several tissue-engineering approaches have attempted regeneration of the dental pulp tissue. Although several studies have highlighted the potential of dental stem cells, none have transitioned into a clinical setting owing to limited availability of dental stem cells and the need for growth factor delivery systems. Our strategy is to utilize the intact ECM of pulp cells to drive lineage specific differentiation of bone marrow derived mesenchymal stem cells. From a clinical perspective, pulp ECM scaffolds can be generated using cell lines and patient specific somatic stem cells can be used for regeneration. Our published results have shown the feasibility of using pulp ECM scaffolds for odontogenic differentiation of non-dental mesenchymal cells. This focused review discusses the issues surrounding dental pulp tissue regeneration and the potential of our strategy to overcome these issues. PMID:25954205

  20. Observations on anatomical aspects of the fruit, leaf and stem tissues of four Citrullus spp.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Morphological characteristics of the fruit, stem and leaf tissues of four species of Citrullus (L.) Schrad. were examined using standard histological methods. Plant materials included the cultivated watermelon (C. lanatus (Thunb.) Matsum. & Nakai) and three of its related species; C. colocynthis (...

  1. Testing for Starch, Respiring Tissues, and Vascular Bundles: Inquiry-Based Seed and Stem Anatomy Labs.

    ERIC Educational Resources Information Center

    Florine, Sara; Hammond, Paul; Pomart, Katrina; Balschweid, Mark

    2002-01-01

    Describes some inquiry-based labs in which students identify starch in popped popcorn, then determine whether starch is present in the kernels prior to them being cooked. Students distinguish monocot and dicot stems as well as determining whether boiling kills tissues in seeds that have been soaked in water. (DDR)

  2. Tissue Engineering Stem Cells – An e-Governance Strategy

    PubMed Central

    Grange, Simon

    2011-01-01

    The rules of governance are changing. They are necessarily becoming more stringent as interventions offered to treat conditions carry unpredictable side effects, often associated with novel therapeutic vectors. The clinical relevance of this relates to the obligations of those involved in research, to ensure the best protection for subjects whilst encouraging the development of the field. Existing evidence supports the concept of e-Governance both in operational health research and more broadly in the strategic domain of policy formation. Building on the impact of the UK Comprehensive Research Network and recent EU Directives, it is now possible to focus on the issues of regulation for cell therapies in musculoskeletal science through the development of the Advanced Therapeutic Medicinal Products (ATMP) category of research products. This article reviews the framework that has borne this and the need for more detailed Virtual Research Integration and Collaboration (VRIC) systems to ensure regulatory compliance. Technology research and development plans must develop in close association between tissue engineering and treating clinicians. The scope of this strategy relates to the handling of human tissues the transport and storage of specimens in accordance with current EU directives and the Human Tissue Authority (HTA) regulations. PMID:21886693

  3. Physicochemical Control of Adult Stem Cell Differentiation: Shedding Light on Potential Molecular Mechanisms

    DTIC Science & Technology

    2010-01-01

    applications, including tissue engineering, requires an understanding of the cell-cell and cell-environment interactions. To this end, recent efforts have been...restricted locations to allow continuation of the cycle of life [1]. These tissue -specific stem cells have been identified in the bone marrow [2], brain [3...relatively easy to isolate and differentiate into neuronal cells, and therefore may be useful for tissue engineering strategies to repair and regenerate

  4. Tissue engineering for damaged surface and lining epithelia: stem cells, current clinical applications, and available engineered tissues.

    PubMed

    Guerra, Liliana; Dellambra, Elena; Panacchia, Laura; Paionni, Emanuel

    2009-06-01

    Tissue engineering is an important tool for the treatment of damaged surface and lining epithelia. A source of cells and biocompatible substrates upon which cells can grow and differentiate are key components of this technology. Cultured normal human epithelial cells reconstitute sheets of stratified epithelia that retain biochemical and histological characteristics as well as specific differentiation features of the original donor site. Maintenance of epithelial stem cells in culture and a well-prepared receiving wound bed allow to permanently regenerate full-thickness wounds by means of in vitro reconstituted epithelia. Further, cultured cells produce growth factors and extracellular matrix (ECM) components that help resident cells to contribute to the wound-healing process. Biological matrices enhance the performance of the in vitro reconstituted epithelia. Owing to their similarity to the ECM, natural polymers offer the advantage of being similar to macromolecules that the human environment is prepared to recognize. They also maintain biological information and physical and chemical features that are instructive for cells used to populate them. This article discusses the developments of tissues engineered for cutaneous and mucosal regeneration. Native tissues and their stem cells are also considered, to enhance understanding of the extensive field of tissue reconstruction.

  5. Phases I–III Clinical Trials Using Adult Stem Cells

    PubMed Central

    Sanz-Ruiz, Ricardo; Gutiérrez Ibañes, Enrique; Arranz, Adolfo Villa; Fernández Santos, María Eugenia; Fernández, Pedro L. Sánchez; Fernández-Avilés, Francisco

    2010-01-01

    First randomized clinical trials have demonstrated that stem cell therapy can improve cardiac recovery after the acute phase of myocardial ischemia and in patients with chronic ischemic heart disease. Nevertheless, some trials have shown that conflicting results and uncertainties remain in the case of mechanisms of action and possible ways to improve clinical impact of stem cells in cardiac repair. In this paper we will examine the evidence available, analyze the main phase I and II randomized clinical trials and their limitations, discuss the key points in the design of future trials, and depict new directions of research in this fascinating field. PMID:21076533

  6. Characterization of a mesenchymal-like stem cell population from osteophyte tissue.

    PubMed

    Singh, Sanjleena; Jones, Ben J; Crawford, Ross; Xiao, Yin

    2008-04-01

    Osteophytes are a distinct feature of osteoarthritis (OA). Their formation may be related to pluripotential cells in the periosteum responding to stimulus during OA. This study aimed to isolate stem cells from osteophyte tissues and to characterize their phenotype, proliferation, and differentiation potential, as well as their immunomodulatory properties. Osteophyte-derived cells were isolated from osteophyte tissue samples collected during knee replacement surgery. These cells were characterized by the expression of cell-surface antigens, differentiation potential into mesenchymal lineages, growth kinetics, and modulation of alloimmune responses. Multipotential stem cells were identified from all osteophyte samples, namely osteophyte-derived mesenchymal stem cells (oMSCs). The surface antigen expression of oMSCs was consistent with that of MSCs; they lacked the hematopoietic and common leukocyte markers (CD34, CD45) while expressing those related to adhesion (CD29, CD166, CD44) and stem cells (CD90, CD105, CD73). The proliferation capacity of oMSCs in culture was superior to that of bone marrow-derived MSCs (bMSCs), and these cells readily differentiated into tissues of the mesenchymal lineages. oMSCs also demonstrated the ability to suppress allogeneic T cell proliferation, which was associated with the expression of the tryptophan-degrading enzyme indoleamine 2,3-dioxygenase (IDO). Our results showed that osteophyte-derived cells had similar properties to MSCs in the expression of antigen phenotype, differential potential, and suppression of alloimmune response. Furthermore, when compared to bMSCs, oMSCs maintained a higher proliferative capacity, which may offer new insights of the tissue formation and potentially an alternative source for therapeutic stem cell-based tissue regeneration.

  7. Empowering Adult Stem Cells for Myocardial Regeneration V2.0: Success in Small Steps

    PubMed Central

    Broughton, Kathleen; Sussman, Mark A.

    2016-01-01

    Much has changed since our survey of the landscape for myocardial regeneration powered by adult stem cells four years ago (Mohsin et al., Empowering adult stem cells for myocardial regeneration. Circ Res. 2011; 109(12):1415–1428) [1]. The intervening years since that first review has witnessed an explosive expansion of studies that advance both understanding and implementation of adult stem cells in promoting myocardial repair. Painstaking research from innumerable laboratories throughout the world is prying open doors that may lead to restoration of myocardial structure and function in the wake of pathologic injury. This global effort has produced deeper mechanistic comprehension coupled with an evolving appreciation for the complexity of myocardial regeneration in the adult context. Undaunted by both known and (as yet) unknown challenges, pursuit of myocardial regenerative medicine mediated by adult stem cell therapy has gathered momentum fueled by tantalizing clues and visionary goals. This concise review takes a somewhat different perspective than our initial treatise, taking stock of the business sector that has become an integral part of the field while concurrently updating “state of affairs” in cutting edge research. Looking retrospectively at advancement over the years as all reviews eventually must, the fundamental lesson to be learned is best explained by Jonatan Mårtensson: “Success will never be a big step in the future. Success is a small step taken just now.” PMID:26941423

  8. Using polymeric materials to control stem cell behavior for tissue regeneration.

    PubMed

    Zhang, Nianli; Kohn, David H

    2012-03-01

    Patients with organ failure often suffer from increased morbidity and decreased quality of life. Current strategies of treating organ failure have limitations, including shortage of donor organs, low efficiency of grafts, and immunological problems. Tissue engineering emerged about two decades ago as a strategy to restore organ function with a living, functional engineered substitute. However, the ability to engineer a functional organ is limited by a limited understanding of the interactions between materials and cells that are required to yield functional tissue equivalents. Polymeric materials are one of the most promising classes of materials for use in tissue engineering, due to their biodegradability, flexibility in processing and property design, and the potential to use polymer properties to control cell function. Stem cells offer potential in tissue engineering because of their unique capacity to self-renew and differentiate into neurogenic, osteogenic, chondrogenic, and myogenic lineages under appropriate stimuli from extracellular components. This review examines recent advances in stem cell-polymer interactions for tissue regeneration, specifically highlighting control of polymer properties to direct adhesion, proliferation, and differentiation of stem cells, and how biomaterials can be designed to provide some of the stimuli to cells that the natural extracellular matrix does.

  9. Origins of adult pigmentation: diversity in pigment stem cell lineages and implications for pattern evolution

    PubMed Central

    Spiewak, Jessica E.

    2014-01-01

    Summary Teleosts comprise about half of all vertebrate species and exhibit an extraordinary diversity of adult pigment patterns that function in shoaling, camouflage and mate choice and have played important roles in speciation. Here, we review recent studies that have identified several distinct neural crest lineages, with distinct genetic requirements, that give rise to adult pigment cells in fishes. These lineages include post-embryonic, peripheral nerve associated stem cells that generate black melanophores and iridescent iridophores, cells derived directly from embryonic neural crest cells that generate yellow-orange xanthophores, and bipotent stem cells that generate both melanophores and xanthophores. This complexity in adult chromatophore lineages has implications for our understanding of adult traits, melanoma, and the evolutionary diversification of pigment cell lineages and patterns. PMID:25421288

  10. Mitochondria modify exercise-induced development of stem cell-derived neurons in the adult brain.

    PubMed

    Steib, Kathrin; Schäffner, Iris; Jagasia, Ravi; Ebert, Birgit; Lie, D Chichung

    2014-05-07

    Neural stem cells in the adult mammalian hippocampus continuously generate new functional neurons, which modify the hippocampal network and significantly contribute to cognitive processes and mood regulation. Here, we show that the development of new neurons from stem cells in adult mice is paralleled by extensive changes to mitochondrial mass, distribution, and shape. Moreover, exercise-a strong modifier of adult hippocampal neurogenesis-accelerates neuronal maturation and induces a profound increase in mitochondrial content and the presence of mitochondria in dendritic segments. Genetic inhibition of the activity of the mitochondrial fission factor dynamin-related protein 1 (Drp1) inhibits neurogenesis under basal and exercise conditions. Conversely, enhanced Drp1 activity furthers exercise-induced acceleration of neuronal maturation. Collectively, these results indicate that adult hippocampal neurogenesis requires adaptation of the mitochondrial compartment and suggest that mitochondria are targets for enhancing neurogenesis-dependent hippocampal plasticity.

  11. Origins of adult pigmentation: diversity in pigment stem cell lineages and implications for pattern evolution.

    PubMed

    Parichy, David M; Spiewak, Jessica E

    2015-01-01

    Teleosts comprise about half of all vertebrate species and exhibit an extraordinary diversity of adult pigment patterns that function in shoaling, camouflage, and mate choice and have played important roles in speciation. Here, we review studies that have identified several distinct neural crest lineages, with distinct genetic requirements, that give rise to adult pigment cells in fishes. These lineages include post-embryonic, peripheral nerve-associated stem cells that generate black melanophores and iridescent iridophores, cells derived directly from embryonic neural crest cells that generate yellow-orange xanthophores, and bipotent stem cells that generate both melanophores and xanthophores. This complexity in adult chromatophore lineages has implications for our understanding of adult traits, melanoma, and the evolutionary diversification of pigment cell lineages and patterns.

  12. Stem cells from the fat tissue of rabbits: an easy-to-find experimental source.

    PubMed

    Torres, Fabrício Carvalho; Rodrigues, Consuelo Junqueira; Stocchero, Ithamar Nogueira; Ferreira, Marcus Castro

    2007-01-01

    Stem cells, because of their pluripotentiality and unlimited capacity for self-renewal, project great promise for tissue engineering and are expected to allow significant advances for distinct reconstructive procedures. This study aimed to establish a versatile experimental model with potential application to distinct lines of research in plastic surgery. The search was guided by the need for mesenchymal stem cells that can be easily obtained for laboratory research. The authors studied the anatomy of a number of animals as potential donors and indicated the white New Zealand rabbit (Oryctolagus cuniculus) for this purpose. The animals of this species present definite areas of lipid tissue on their back, allowing easy access to the tissue by either exeresis or liposuction.

  13. Human adipose tissue-derived mesenchymal stem cells differentiate into insulin, somatostatin, and glucagon expressing cells

    SciTech Connect

    Timper, Katharina; Seboek, Dalma; Eberhardt, Michael; Linscheid, Philippe; Christ-Crain, Mirjam; Keller, Ulrich; Mueller, Beat; Zulewski, Henryk . E-mail: henryk.zulewski@unibas.ch

    2006-03-24

    Mesenchymal stem cells (MSC) from mouse bone marrow were shown to adopt a pancreatic endocrine phenotype in vitro and to reverse diabetes in an animal model. MSC from human bone marrow and adipose tissue represent very similar cell populations with comparable phenotypes. Adipose tissue is abundant and easily accessible and could thus also harbor cells with the potential to differentiate in insulin producing cells. We isolated human adipose tissue-derived MSC from four healthy donors. During the proliferation period, the cells expressed the stem cell markers nestin, ABCG2, SCF, Thy-1 as well as the pancreatic endocrine transcription factor Isl-1. The cells were induced to differentiate into a pancreatic endocrine phenotype by defined culture conditions within 3 days. Using quantitative PCR a down-regulation of ABCG2 and up-regulation of pancreatic developmental transcription factors Isl-1, Ipf-1, and Ngn3 were observed together with induction of the islet hormones insulin, glucagon, and somatostatin.

  14. Stem Cell Differentiation Toward the Myogenic Lineage for Muscle Tissue Regeneration: A Focus on Muscular Dystrophy.

    PubMed

    Ostrovidov, Serge; Shi, Xuetao; Sadeghian, Ramin Banan; Salehi, Sahar; Fujie, Toshinori; Bae, Hojae; Ramalingam, Murugan; Khademhosseini, Ali

    2015-12-01

    Skeletal muscle tissue engineering is one of the important ways for regenerating functionally defective muscles. Among the myopathies, the Duchenne muscular dystrophy (DMD) is a progressive disease due to mutations of the dystrophin gene leading to progressive myofiber degeneration with severe symptoms. Although current therapies in muscular dystrophy are still very challenging, important progress has been made in materials science and in cellular technologies with the use of stem cells. It is therefore useful to review these advances and the results obtained in a clinical point of view. This article focuses on the differentiation of stem cells into myoblasts, and their application in muscular dystrophy. After an overview of the different stem cells that can be induced to differentiate into the myogenic lineage, we introduce scaffolding materials used for muscular tissue engineering. We then described some widely used methods to differentiate different types of stem cell into myoblasts. We highlight recent insights obtained in therapies for muscular dystrophy. Finally, we conclude with a discussion on stem cell technology. We discussed in parallel the benefits brought by the evolution of the materials and by the expansion of cell sources which can differentiate into myoblasts. We also discussed on future challenges for clinical applications and how to accelerate the translation from the research to the clinic in the frame of DMD.

  15. Different Tissue-Derived Stem Cells: A Comparison of Neural Differentiation Capability

    PubMed Central

    Bonaventura, Gabriele; Chamayou, Sandrine; Liprino, Annalisa; Guglielmino, Antonino; Fichera, Michele; Caruso, Massimo; Barcellona, Maria Luisa

    2015-01-01

    Background Stem cells are capable of self-renewal and differentiation into a wide range of cell types with multiple clinical and therapeutic applications. Stem cells are providing hope for many diseases that currently lack effective therapeutic methods, including strokes, Huntington's disease, Alzheimer's and Parkinson's disease. However, the paucity of suitable cell types for cell replacement therapy in patients suffering from neurological disorders has hampered the development of this promising therapeutic approach. Aim The innovative aspect of this study has been to evaluate the neural differentiation capability of different tissue-derived stem cells coming from different tissue sources such as bone marrow, umbilical cord blood, human endometrium and amniotic fluid, cultured under the same supplemented media neuro-transcription factor conditions, testing the expression of neural markers such as GFAP, Nestin and Neurofilaments using the immunofluorescence staining assay and some typical clusters of differentiation such as CD34, CD90, CD105 and CD133 by using the cytofluorimetric test assay. Results Amniotic fluid derived stem cells showed a more primitive phenotype compared to the differentiating potential demonstrated by the other stem cell sources, representing a realistic possibility in the field of regenerative cell therapy suitable for neurodegenerative diseases. PMID:26517263

  16. Human mesenchymal stem cells: a bank perspective on the isolation, characterization and potential of alternative sources for the regeneration of musculoskeletal tissues.

    PubMed

    Moroni, Lorenzo; Fornasari, Pier Maria

    2013-04-01

    The continuous discovery of human mesenchymal stem cells (hMSCs) in different tissues is stirring up a tremendous interest as a cell source for regenerative medicine therapies. Historically, hMSCs have been always considered a sub-population of mononuclear cells present in the bone marrow (BM). Although BM-hMSCs are still nowadays considered as the most promising mesenchymal stem cell population to reach the clinics due to their capacity to differentiate into multiple tissues, hMSCs derived from other adult and fetal tissues have also demonstrated to possess similar differentiation capacities. Furthermore, different reports have highlighted a higher recurrence of hMSCs in some of these tissues as compared to BM. This offer a fascinating panorama for cell banking, since the creation of a stem cell factory could be envisioned where hMSCs are stocked and used for ad hoc clinical applications. In this review, we summarize the main findings and state of the art in hMSCs isolation, characterization, and differentiation from alternative tissue sources and we attempt to compare their potency for musculoskeletal regeneration.

  17. Ethical and Regulatory Challenges with Autologous Adult Stem Cells: A Comparative Review of International Regulations.

    PubMed

    Lysaght, Tamra; Kerridge, Ian H; Sipp, Douglas; Porter, Gerard; Capps, Benjamin J

    2017-02-28

    Cell and tissue-based products, such as autologous adult stem cells, are being prescribed by physicians across the world for diseases and illnesses that they have neither been approved for or been demonstrated as safe and effective in formal clinical trials. These doctors often form part of informal transnational networks that exploit differences and similarities in the regulatory systems across geographical contexts. In this paper, we examine the regulatory infrastructure of five geographically diverse but socio-economically comparable countries with the aim of identifying similarities and differences in how these products are regulated and governed within clinical contexts. We find that while there are many subtle technical differences in how these regulations are implemented, they are sufficiently similar that it is difficult to explain why these practices appear more prevalent in some countries and not in others. We conclude with suggestions for how international governance frameworks might be improved to discourage the exploitation of vulnerable patient populations while enabling innovation in the clinical application of cellular therapies.

  18. Mechanical unloading of bone in microgravity reduces mesenchymal and hematopoietic stem cell-mediated tissue regeneration.

    PubMed

    Blaber, E A; Dvorochkin, N; Torres, M L; Yousuf, R; Burns, B P; Globus, R K; Almeida, E A C

    2014-09-01

    Mechanical loading of mammalian tissues is a potent promoter of tissue growth and regeneration, whilst unloading in microgravity can cause reduced tissue regeneration, possibly through effects on stem cell tissue progenitors. To test the specific hypothesis that mechanical unloading alters differentiation of bone marrow mesenchymal and hematopoietic stem cell lineages, we studied cellular and molecular aspects of how bone marrow in the mouse proximal femur responds to unloading in microgravity. Trabecular and cortical endosteal bone surfaces in the femoral head underwent significant bone resorption in microgravity, enlarging the marrow cavity. Cells isolated from the femoral head marrow compartment showed significant down-regulation of gene expression markers for early mesenchymal and hematopoietic differentiation, including FUT1(-6.72), CSF2(-3.30), CD90(-3.33), PTPRC(-2.79), and GDF15(-2.45), but not stem cell markers, such as SOX2. At the cellular level, in situ histological analysis revealed decreased megakaryocyte numbers whilst erythrocytes were increased 2.33 fold. Furthermore, erythrocytes displayed elevated fucosylation and clustering adjacent to sinuses forming the marrow-blood barrier, possibly providing a mechanistic basis for explaining spaceflight anemia. Culture of isolated bone marrow cells immediately after microgravity exposure increased the marrow progenitor's potential for mesenchymal differentiation into in-vitro mineralized bone nodules, and hematopoietic differentiation into osteoclasts, suggesting an accumulation of undifferentiated progenitors during exposure to microgravity. These results support the idea that mechanical unloading of mammalian tissues in microgravity is a strong inhibitor of tissue growth and regeneration mechanisms, acting at the level of early mesenchymal and hematopoietic stem cell differentiation.

  19. Nuclear receptor regulation of stemness and stem cell differentiation

    PubMed Central

    Jeong, Yangsik

    2009-01-01

    Stem cells include a diverse number of toti-, pluri-, and multi-potent cells that play important roles in cellular genesis and differentiation, tissue development, and organogenesis. Genetic regulation involving various transcription factors results in the self-renewal and differentiation properties of stem cells. The nuclear receptor (NR) superfamily is composed of 48 ligand-activated transcription factors involved in diverse physiological functions such as metabolism, development, and reproduction. Increasing evidence shows that certain NRs function in regulating stemness or differentiation of embryonic stem (ES) cells and tissue-specific adult stem cells. Here, we review the role of the NR superfamily in various aspects of stem cell biology, including their regulation of stemness, forward- and trans-differentiation events; reprogramming of terminally differentiated cells; and interspecies differences. These studies provide insights into the therapeutic potential of the NR superfamily in stem cell therapy and in treating stem cell-associated diseases (e.g., cancer stem cell). PMID:19696553

  20. The Regulatory Effects of Long Noncoding RNA-ANCR on Dental Tissue-Derived Stem Cells

    PubMed Central

    Jia, Qian; Chen, Xiaolin; Jiang, Wenkai; Wang, Wei

    2016-01-01

    Long noncoding RNAs (lncRNA) have been recognized as important regulators in diverse biological processes, such as transcriptional regulation, stem cell proliferation, and differentiation. Previous study has demonstrated that lncRNA-ANCR (antidifferentiation ncRNA) plays a key role in regulating the proliferation and osteogenic differentiation of periodontal ligament stem cells (PDLSCs). However, little is known about the role of ANCR in regulating other types of dental tissue-derived stem cells (DTSCs) behaviours (including proliferation and multiple-potential of differentiation). In this study, we investigated the regulatory effects of lncRNA-ANCR on the proliferation and differentiation (including osteogenic, adipogenic, and neurogenic differentiation) of DTSCs, including dental pulp stem cells (DPSCs), PDLSCs, and stem cells from the apical papilla (SCAP) by downregulation of lncRNA-ANCR. We found that downregulation of ANCR exerted little effect on proliferation of DPSCs and SCAP but promoted the osteogenic, adipogenic, and neurogenic differentiation of DTSCs. These data provide an insight into the regulatory effects of long noncoding RNA-ANCR on DTSCs and indicate that ANCR is a very important regulatory factor in stem cell differentiation. PMID:27648074

  1. GMP-compliant human adipose tissue-derived mesenchymal stem cells for cellular therapy.

    PubMed

    Aghayan, Hamid-Reza; Goodarzi, Parisa; Arjmand, Babak

    2015-01-01

    Stem cells, which can be derived from different sources, demonstrate promising therapeutic evidences for cellular therapies. Among various types of stem cell, mesenchymal stem cells are one of the most common stem cells that are used in cellular therapy. Human subcutaneous adipose tissue provides an easy accessible source of mesenchymal stem cells with some considerable advantages. Accordingly, various preclinical and clinical investigations have shown enormous potential of adipose-derived stromal cells in regenerative medicine. Consequently, increasing clinical applications of these cells has elucidated the importance of safety concerns regarding clinical transplantation. Therefore, clinical-grade preparation of adipose-derived stromal cells in accordance with current good manufacturing practice guidelines is an essential part of their clinical applications to ensure the safety, quality, characteristics, and identity of cell products. Additionally, GMP-compliant cell manufacturing involves several issues to provide a quality assurance system during translation from the basic stem cell sciences into clinical investigations and applications. On the other hand, advanced cellular therapy requires extensive validation, process control, and documentation. It also evidently elucidates the critical importance of production methods and probable risks. Therefore, implementation of a quality management and assurance system in accordance with GMP guidelines can greatly reduce these risks particularly in the higher-risk category or "more than minimally manipulated" products.

  2. Female mice lack adult germ-line stem cells but sustain oogenesis using stable primordial follicles.

    PubMed

    Lei, Lei; Spradling, Allan C

    2013-05-21

    Whether or not mammalian females generate new oocytes during adulthood from germ-line stem cells to sustain the ovarian follicle pool has recently generated controversy. We used a sensitive lineage-labeling system to determine whether stem cells are needed in female adult mice to compensate for follicular losses and to directly identify active germ-line stem cells. Primordial follicles generated during fetal life are highly stable, with a half-life during adulthood of 10 mo, and thus are sufficient to sustain adult oogenesis without a source of renewal. Moreover, in normal mice or following germ-cell depletion with Busulfan, only stable, single oocytes are lineage-labeled, rather than cell clusters indicative of new oocyte formation. Even one germ-line stem cell division per 2 wk would have been detected by our method, based on the kinetics of fetal follicle formation. Thus, adult female mice neither require nor contain active germ-line stem cells or produce new oocytes in vivo.

  3. Adult Tissue Sources for New β-cells

    PubMed Central

    Nichols, Robert J.; New, Connie; Annes, Justin P.

    2014-01-01

    The diabetes pandemic incurs extraordinary public health and financial costs that are projected to expand for the foreseeable future. Consequently, the development of definitive therapies for diabetes is a priority. Currently, a wide spectrum of therapeutic strategies, from implantable insulin-delivery devices to transplantation-based cell replacement therapy, to β-cell regeneration, focus on replacing the lost insulin-production capacity of diabetics. Among these, β-cell regeneration remains promising but heretofore unproven. Indeed, recent experimental work has uncovered surprising biology that underscores the potential therapeutic benefit of β-cell regeneration. These studies have elucidated a variety of sources for the endogenous production of new β-cells from existing cells. First, β-cells, long thought to be post-mitotic, have demonstrate potential for regenerative capacity. Second, the presence of pancreatic facultative endocrine progenitor cells has been established. Third, the malleability of cellular identity has availed the possibility of generating β-cells from other differentiated cell types. Here, we will review the exciting developments surrounding endogenous sources of β-cell production and consider the potential of realizing a regenerative therapy for diabetes from adult tissues. PMID:24345765

  4. Neural stem cells in the adult ciliary epithelium express GFAP and are regulated by Wnt signaling

    SciTech Connect

    Das, Ani V.; Zhao Xing; James, Jackson; Kim, Min; Cowan, Kenneth H.; Ahmad, Iqbal . E-mail: iahmad@unmc.edu

    2006-01-13

    The identification of neural stem cells with retinal potential in the ciliary epithelium (CE) of the adult mammals is of considerable interest because of their potential for replacing or rescuing degenerating retinal neurons in disease or injury. The evaluation of such a potential requires characterization of these cells with regard to their phenotypic properties, potential, and regulatory mechanisms. Here, we demonstrate that rat CE stem cells/progenitors in neurosphere culture display astrocytic nature in terms of expressing glial intermediate neurofilament protein, GFAP. The GFAP-expressing CE stem cells/progenitors form neurospheres in proliferating conditions and generate neurons when shifted to differentiating conditions. These cells express components of the canonical Wnt pathway and its activation promotes their proliferation. Furthermore, we demonstrate that the activation of the canonical Wnt pathway influences neuronal differentiation of CE stem cells/progenitors in a context dependent manner. Our observations suggest that CE stem cells/progenitors share phenotypic properties and regulatory mechanism(s) with neural stem cells elsewhere in the adult CNS.

  5. Design Principles for Engineering of Tissues from Human Pluripotent Stem Cells

    PubMed Central

    Matthys, Oriane B.; Hookway, Tracy A.; McDevitt, Todd C.

    2016-01-01

    Recent advances in human pluripotent stem cell (hPSC) technologies have enabled the engineering of human tissue constructs for developmental studies, disease modeling, and drug screening platforms. In vitro tissue formation can be generally described at three levels of cellular organization. Multicellular hPSC constructs are initially formed either with polymeric scaffold materials or simply via self-assembly, adhesive mechanisms. Heterotypic interactions within hPSC tissue constructs can be achieved by physically mixing independently differentiated cell populations or coaxed to simultaneously co-emerge from a common population of undifferentiated cells. Higher order tissue architecture can be engineered by imposing external spatial constraints, such as molds and scaffolds, or depend upon cell-driven organization that exploits endogenous innate developmental mechanisms. The multicellular, heterogeneous, and highly organized structure of hPSC constructs ultimately dictates the resulting form and function of in vitro engineered human tissue models. PMID:27330934

  6. Mesenchymal stem cells from the outer ear: a novel adult stem cell model system for the study of adipogenesis.

    PubMed

    Rim, Jong-Seop; Mynatt, Randall L; Gawronska-Kozak, Barbara

    2005-07-01

    Adipocytes arise from multipotent stem cells of mesodermal origin, which also give rise to the muscle, bone, and cartilage lineages. However, signals and early molecular events that commit multipotent stem cells into the adipocyte lineage are not well established mainly due to lack of an adequate model system. We have identified a novel source of adult stem cells from the external murine ears referred to here as an ear mesenchymal stem cells (EMSC). EMSC have been isolated from several standard and mutant strains of mice. They are self-renewing, clonogenic, and multipotent, since they give rise to osteocytes, chondrocytes, and adipocytes. The in vitro characterization of EMSC indicates very facile adipogenic differentiation. Morphological, histochemical, and molecular analysis after the induction of differentiation showed that EMSC maintain adipogenic potentials up to fifth passage. A comparison of EMSC to the stromal-vascular (S-V) fraction of fat depots, under identical culture conditions (isobutyl-methylxanthine, dexamethasone, and insulin), revealed much more robust and consistent adipogenesis in EMSC than in the S-V fraction. In summary, we show that EMSC can provide a novel, easily obtainable, primary culture model for the study of adipogenesis.

  7. Genomic selection for quantitative adult plant stem rust resistance in wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Quantitative adult plant resistance (APR) to stem rust (Puccinia graminis f. sp. tritici) is an important breeding target in wheat (Triticum aestivum L.) and a potential target for genomic selection (GS). To evaluate the relative importance of known APR loci in applying genomic selection, we charact...

  8. Strategies to enhance umbilical cord blood stem cell engraftment in adult patients

    PubMed Central

    Delaney, Colleen; Ratajczak, Mariusz Z; Laughlin, Mary J

    2010-01-01

    Umbilical cord blood (UCB) has been used successfully as a source of hematopoietic stem cells (HSCs) for allogeneic transplantation in children and adults in the treatment of hematologic diseases. However, compared with marrow or mobilized peripheral blood stem cell grafts from adult donors, significant delays in the rates and kinetics of neutrophil and platelet engraftment are noted after UCB transplant. These differences relate in part to the reduced numbers of HSCs in UCB grafts. To improve the rates and kinetics of engraftment of UCB HSC, several strategies have been proposed, including ex vivo expansion of UCB HSCs, addition of third-party mesenchymal cells, intrabone delivery of HSCs, modulation of CD26 expression, and infusion of two UCB grafts. This article will focus on ex vivo expansion of UCB HSCs and strategies to enhance UCB homing as potential solutions to overcome the problem of low stem cell numbers in a UCB graft. PMID:20835351

  9. Biophysical properties and functional significance of stem water storage tissues in Neotropical savanna trees.

    PubMed

    Scholz, Fabian G; Bucci, Sandra J; Goldstein, Guillermo; Meinzer, Frederick C; Franco, Augusto C; Miralles-Wilhelm, Fernando

    2007-02-01

    Biophysical characteristics of sapwood and outer parenchyma water storage compartments were studied in stems of eight dominant Brazilian Cerrado tree species to assess the impact of differences in tissue capacitance on whole-plant water relations. The rate of decline in tissue water potential with relative water content (RWC) was greater in the outer parenchyma than in the sapwood for most of the species, resulting in tissue-and species-specific differences in capacitance. Sapwood capacitance on a tissue volume basis ranged from 40 to 160 kg m-3 MPa-1, whereas outer parenchyma capacitance ranged from 25 to only 60 kg m-3 MPa-1. In addition, osmotic potentials at full turgor and at the turgor loss point were more negative for the outer parenchyma compared with the sapwood, and the maximum bulk elastic modulus was higher for the outer parenchyma than for the sapwood. Sapwood capacitance decreased linearly with increasing sapwood density across species, but there was no significant correlation between outer parenchyma capacitance and tissue density. Midday leaf water potential, the total hydraulic conductance of the soil/leaf pathway and stomatal conductance to water vapour (gs) all increased with stem volumetric capacitance, or with the relative contribution of stored water to total daily transpiration. However, the difference between the pre-dawn water potential of non-transpiring leaves and the weighted average soil water potential, a measure of the water potential disequilibrium between the plant and soil, increased asymptotically with total stem capacitance across species, implying that overnight recharge of water storage compartments was incomplete in species with greater capacitance. Overall, stem capacitance contributes to homeostasis in the diurnal and seasonal water balance of Cerrado trees.

  10. Fetal programming of adult Leydig cell function by androgenic effects on stem/progenitor cells.

    PubMed

    Kilcoyne, Karen R; Smith, Lee B; Atanassova, Nina; Macpherson, Sheila; McKinnell, Chris; van den Driesche, Sander; Jobling, Matthew S; Chambers, Thomas J G; De Gendt, Karel; Verhoeven, Guido; O'Hara, Laura; Platts, Sophie; Renato de Franca, Luiz; Lara, Nathália L M; Anderson, Richard A; Sharpe, Richard M

    2014-05-06

    Fetal growth plays a role in programming of adult cardiometabolic disorders, which in men, are associated with lowered testosterone levels. Fetal growth and fetal androgen exposure can also predetermine testosterone levels in men, although how is unknown, because the adult Leydig cells (ALCs) that produce testosterone do not differentiate until puberty. To explain this conundrum, we hypothesized that stem cells for ALCs must be present in the fetal testis and might be susceptible to programming by fetal androgen exposure during masculinization. To address this hypothesis, we used ALC ablation/regeneration to identify that, in rats, ALCs derive from stem/progenitor cells that express chicken ovalbumin upstream promoter transcription factor II. These stem cells are abundant in the fetal testis of humans and rodents, and lineage tracing in mice shows that they develop into ALCs. The stem cells also express androgen receptors (ARs). Reduction in fetal androgen action through AR KO in mice or dibutyl phthalate (DBP) -induced reduction in intratesticular testosterone in rats reduced ALC stem cell number by ∼40% at birth to adulthood and induced compensated ALC failure (low/normal testosterone and elevated luteinizing hormone). In DBP-exposed males, this failure was probably explained by reduced testicular steroidogenic acute regulatory protein expression, which is associated with increased histone methylation (H3K27me3) in the proximal promoter. Accordingly, ALCs and ALC stem cells immunoexpressed increased H3K27me3, a change that was also evident in ALC stem cells in fetal testes. These studies highlight how a key component of male reproductive development can fundamentally reprogram adult hormone production (through an epigenetic change), which might affect lifetime disease risk.

  11. Stroke Increases Neural Stem Cells and Angiogenesis in the Neurogenic Niche of the Adult Mouse

    PubMed Central

    Zhang, Rui Lan; Chopp, Michael; Roberts, Cynthia; Liu, Xianshuang; Wei, Min; Nejad-Davarani, Siamak P.; Wang, Xinli; Zhang, Zheng Gang

    2014-01-01

    The unique cellular and vascular architecture of the adult ventricular-subventricular zone (V/SVZ) neurogenic niche plays an important role in regulating neural stem cell function. However, the in vivo identification of neural stem cells and their relationship to blood vessels within this niche in response to stroke remain largely unknown. Using whole-mount preparation of the lateral ventricle wall, we examined the architecture of neural stem cells and blood vessels in the V/SVZ of adult mouse over the course of 3 months after onset of focal cerebral ischemia. Stroke substantially increased the number of glial fibrillary acidic protein (GFAP) positive neural stem cells that are in contact with the cerebrospinal fluid (CSF) via their apical processes at the center of pinwheel structures formed by ependymal cells residing in the lateral ventricle. Long basal processes of these cells extended to blood vessels beneath the ependymal layer. Moreover, stroke increased V/SVZ endothelial cell proliferation from 2% in non-ischemic mice to 12 and 15% at 7 and 14 days after stroke, respectively. Vascular volume in the V/SVZ was augmented from 3% of the total volume prior to stroke to 6% at 90 days after stroke. Stroke-increased angiogenesis was closely associated with neuroblasts that expanded to nearly encompass the entire lateral ventricular wall in the V/SVZ. These data indicate that stroke induces long-term alterations of the neural stem cell and vascular architecture of the adult V/SVZ neurogenic niche. These post-stroke structural changes may provide insight into neural stem cell mediation of stroke-induced neurogenesis through the interaction of neural stem cells with proteins in the CSF and their sub-ependymal neurovascular interaction. PMID:25437857

  12. The novel steroidal alkaloids dendrogenin A and B promote proliferation of adult neural stem cells

    SciTech Connect

    Khalifa, Shaden A.M.; Medina, Philippe de; Erlandsson, Anna; El-Seedi, Hesham R.; Silvente-Poirot, Sandrine; Poirot, Marc

    2014-04-11

    Highlights: • Dendrogenin A and B are new aminoalkyl oxysterols. • Dendrogenins stimulated neural stem cells proliferation. • Dendrogenins induce neuronal outgrowth from neurospheres. • Dendrogenins provide new therapeutic options for neurodegenerative disorders. - Abstract: Dendrogenin A (DDA) and dendrogenin B (DDB) are new aminoalkyl oxysterols which display re-differentiation of tumor cells of neuronal origin at nanomolar concentrations. We analyzed the influence of dendrogenins on adult mice neural stem cell proliferation, sphere formation and differentiation. DDA and DDB were found to have potent proliferative effects in neural stem cells. Additionally, they induce neuronal outgrowth from neurospheres during in vitro cultivation. Taken together, our results demonstrate a novel role for dendrogenins A and B in neural stem cell proliferation and differentiation which further increases their likely importance to compensate for neuronal cell loss in the brain.

  13. Large-scale live imaging of adult neural stem cells in their endogenous niche.

    PubMed

    Dray, Nicolas; Bedu, Sébastien; Vuillemin, Nelly; Alunni, Alessandro; Coolen, Marion; Krecsmarik, Monika; Supatto, Willy; Beaurepaire, Emmanuel; Bally-Cuif, Laure

    2015-10-15

    Live imaging of adult neural stem cells (aNSCs) in vivo is a technical challenge in the vertebrate brain. Here, we achieve long-term imaging of the adult zebrafish telencephalic neurogenic niche and track a population of >1000 aNSCs over weeks, by taking advantage of fish transparency at near-infrared wavelengths and of intrinsic multiphoton landmarks. This methodology enables us to describe the frequency, distribution and modes of aNSCs divisions across the entire germinal zone of the adult pallium, and to highlight regional differences in these parameters.

  14. Pluripotent stem cell derived hepatocytes: using materials to define cellular differentiation and tissue engineering

    PubMed Central

    Lucendo-Villarin, B.; Rashidi, H.; Cameron, K.

    2016-01-01

    Pluripotent stem cell derived liver cells (hepatocytes) represent a promising alternative to primary tissue for biological and clinical applications. To date, most hepatocyte maintenance and differentiation systems have relied upon the use of animal derived components. This serves as a significant barrier to large scale production and application of stem cell derived hepatocytes. Recently, the use of defined biologics has overcome those limitations in two-dimensional monolayer culture. In order to improve the cell phenotype further, three-dimensional culture systems have been employed to better mimic the in vivo situation, drawing upon materials chemistry, engineering and biology. In this review we discuss efforts in the field, to differentiate pluripotent stem cells towards hepatocytes under defined conditions. PMID:27746914

  15. Pluripotent stem cell derived hepatocytes: using materials to define cellular differentiation and tissue engineering.

    PubMed

    Lucendo-Villarin, B; Rashidi, H; Cameron, K; Hay, D C

    2016-05-28

    Pluripotent stem cell derived liver cells (hepatocytes) represent a promising alternative to primary tissue for biological and clinical applications. To date, most hepatocyte maintenance and differentiation systems have relied upon the use of animal derived components. This serves as a significant barrier to large scale production and application of stem cell derived hepatocytes. Recently, the use of defined biologics has overcome those limitations in two-dimensional monolayer culture. In order to improve the cell phenotype further, three-dimensional culture systems have been employed to better mimic the in vivo situation, drawing upon materials chemistry, engineering and biology. In this review we discuss efforts in the field, to differentiate pluripotent stem cells towards hepatocytes under defined conditions.

  16. Osteoblastic/Cementoblastic and Neural Differentiation of Dental Stem Cells and Their Applications to Tissue Engineering and Regenerative Medicine

    PubMed Central

    Kim, Byung-Chul; Bae, Hojae; Kwon, Il-Keun; Lee, Eun-Jun; Park, Jae-Hong

    2012-01-01

    Recently, dental stem and progenitor cells have been harvested from periodontal tissues such as dental pulp, periodontal ligament, follicle, and papilla. These cells have received extensive attention in the field of tissue engineering and regenerative medicine due to their accessibility and multilineage differentiation capacity. These dental stem and progenitor cells are known to be derived from ectomesenchymal origin formed during tooth development. A great deal of research has been accomplished for directing osteoblastic/cementoblastic differentiation and neural differentiation from dental stem cells. To differentiate dental stem cells for use in tissue engineering and regenerative medicine, there needs to be efficient in vitro differentiation toward the osteoblastic/cementoblastic and neural lineage with well-defined and proficient protocols. This would reduce the likelihood of spontaneous differentiation into divergent lineages and increase the available cell source. This review focuses on the multilineage differentiation capacity, especially into osteoblastic/cementoblastic lineage and neural lineages, of dental stem cells such as dental pulp stem cells (DPSC), dental follicle stem cells (DFSC), periodontal ligament stem cells (PDLSC), and dental papilla stem cells (DPPSC). It also covers various experimental strategies that could be used to direct lineage-specific differentiation, and their potential applications in tissue engineering and regenerative medicine. PMID:22224548

  17. Osteoblastic/cementoblastic and neural differentiation of dental stem cells and their applications to tissue engineering and regenerative medicine.

    PubMed

    Kim, Byung-Chul; Bae, Hojae; Kwon, Il-Keun; Lee, Eun-Jun; Park, Jae-Hong; Khademhosseini, Ali; Hwang, Yu-Shik

    2012-06-01

    Recently, dental stem and progenitor cells have been harvested from periodontal tissues such as dental pulp, periodontal ligament, follicle, and papilla. These cells have received extensive attention in the field of tissue engineering and regenerative medicine due to their accessibility and multilineage differentiation capacity. These dental stem and progenitor cells are known to be derived from ectomesenchymal origin formed during tooth development. A great deal of research has been accomplished for directing osteoblastic/cementoblastic differentiation and neural differentiation from dental stem cells. To differentiate dental stem cells for use in tissue engineering and regenerative medicine, there needs to be efficient in vitro differentiation toward the osteoblastic/cementoblastic and neural lineage with well-defined and proficient protocols. This would reduce the likelihood of spontaneous differentiation into divergent lineages and increase the available cell source. This review focuses on the multilineage differentiation capacity, especially into osteoblastic/cementoblastic lineage and neural lineages, of dental stem cells such as dental pulp stem cells (DPSC), dental follicle stem cells (DFSC), periodontal ligament stem cells (PDLSC), and dental papilla stem cells (DPPSC). It also covers various experimental strategies that could be used to direct lineage-specific differentiation, and their potential applications in tissue engineering and regenerative medicine.

  18. Metal debris concentrations in soft tissues adjacent to loosened femoral stems is higher in uncemented than cemented implants

    PubMed Central

    2014-01-01

    Background There are still many questions related to aseptic femoral stem loosening. Systemic and local immune responses to the implanted “foreign body” is one of the reasons for loosening. The purpose of the study was to measure metal ion concentration (Ti, Co, Cr, Mo, Ni, Al) around loosened femoral stems and compare their levels around uncemented and cemented implants. Methods This paper reports 50 hips operated for isolated stem loosening, in 50 patients at the mean age of 57 years (from 21 to 87). There were 25 cemented (Co,Cr29,Mo,Ni) and 25 uncemented (Ti, Al) stems. The mean follow-up from primary hip replacement to revision was 10.1 years (from 0.5 to 17). During the procedure, scar tissue around the stem was taken for analysis of metal ions. Results The concentrations of titanium and aluminium in soft tissues around uncemented loosened stems were higher than cemented ones (p < 0.001, p < 0.001 respectively). However, no statistically significant differences were observed between both types of stems in terms of ions of the metal of which cemented implants had been made of (Co, Cr, Mo, Ni). Conclusions In soft tissue around a loosened stem, the concentrations of metal ions from implants are much higher in case of uncemented stems than of cemented ones. Metal ions from vitalium femoral heads were found around uncemented stems in similar values to cemented streams. PMID:25098913

  19. Expression of pluripotent stem cell markers in mouse uterine tissue during estrous cycle

    PubMed Central

    Choobineh, Kolsum; Zavareh, Saeed; Salehnia, Mojdeh; Ghorbanian, Mohamad Taghi; paylakhi, Seyed Hassan

    2016-01-01

    It was assumed that uterine stem cells are responsible for the unique regenerative capacity of uterine. Therefore, the aim of the present study was to investigate the expression of the pluripotent stem cell markers in the mice uterine tissue during different stages of estrous cycles. Twelve virgin female NMRI mice (6 to 8 weeks old) were considered at proestrus, estrus, metestrus and diestrus according to the cell types observed in the vaginal smear and underwent hysterectomy operation. Quantitative real-time polymerase chain reaction (PCR) and immunohistochemical staining for pluripotent stem cell markers (SOX2, OCT4, KLF4, and NANOG) were performed. Immunofluorescence staining revealed that expression and localization of the pluripotency markers SOX2, OCT4, KLF4, and NANOG at the protein level were not different throughout estrous cycle. Also, mRNA of pluripotency markers was detected in all tested samples. However, there were no significant differences in their genes expression at each stage and during the estrous cycle. Different hormonal profile during the estrous cycle could not affect expression of pluripotent stem cell markers in uterine tissue. PMID:27872713

  20. Direct Mechanical Stimulation of Stem Cells: A Beating Electromechanically Active Scaffold for Cardiac Tissue Engineering.

    PubMed

    Gelmi, Amy; Cieslar-Pobuda, Artur; de Muinck, Ebo; Los, Marek; Rafat, Mehrdad; Jager, Edwin W H

    2016-06-01

    The combination of stem cell therapy with a supportive scaffold is a promising approach to improving cardiac tissue engineering. Stem cell therapy can be used to repair nonfunctioning heart tissue and achieve myocardial regeneration, and scaffold materials can be utilized in order to successfully deliver and support stem cells in vivo. Current research describes passive scaffold materials; here an electroactive scaffold that provides electrical, mechanical, and topographical cues to induced human pluripotent stem cells (iPS) is presented. The poly(lactic-co-glycolic acid) fiber scaffold coated with conductive polymer polypyrrole (PPy) is capable of delivering direct electrical and mechanical stimulation to the iPS. The electroactive scaffolds demonstrate no cytotoxic effects on the iPS as well as an increased expression of cardiac markers for both stimulated and unstimulated protocols. This study demonstrates the first application of PPy as a supportive electroactive material for iPS and the first development of a fiber scaffold capable of dynamic mechanical actuation.

  1. Mesenchymal stem cells derived from adipose tissue are not affected by renal disease.

    PubMed

    Roemeling-van Rhijn, Marieke; Reinders, Marlies E J; de Klein, Annelies; Douben, Hannie; Korevaar, Sander S; Mensah, Fane K F; Dor, Frank J M F; IJzermans, Jan N M; Betjes, Michiel G H; Baan, Carla C; Weimar, Willem; Hoogduijn, Martin J

    2012-10-01

    Mesenchymal stem cells are a potential therapeutic agent in renal disease and kidney transplantation. Autologous cell use in kidney transplantation is preferred to avoid anti-HLA reactivity; however, the influence of renal disease on mesenchymal stem cells is unknown. To investigate the feasibility of autologous cell therapy in patients with renal disease, we isolated these cells from subcutaneous adipose tissue of healthy controls and patients with renal disease and compared them phenotypically and functionally. The mesenchymal stem cells from both groups showed similar morphology and differentiation capacity, and were both over 90% positive for CD73, CD105, and CD166, and negative for CD31 and CD45. They demonstrated comparable population doubling times, rates of apoptosis, and were both capable of inhibiting allo-antigen- and anti-CD3/CD28-activated peripheral blood mononuclear cell proliferation. In response to immune activation they both increased the expression of pro-inflammatory and anti-inflammatory factors. These mesenchymal stem cells were genetically stable after extensive expansion and, importantly, were not affected by uremic serum. Thus, mesenchymal stem cells of patients with renal disease have similar characteristics and functionality as those from healthy controls. Hence, our results indicate the feasibility of their use in autologous cell therapy in patients with renal disease.

  2. The Modulatable Stem Cell Niche: Tissue Interactions during Hair and Feather Follicle Regeneration.

    PubMed

    Chen, Chih-Chiang; Plikus, Maksim V; Tang, Pin-Chi; Widelitz, Randall B; Chuong, Cheng Ming

    2016-04-10

    Hair and feathers are unique because (1) their stem cells are contained within a follicle structure, (2) they undergo cyclic regeneration repetitively throughout life, (3) regeneration occurs physiologically in healthy individuals and (4) regeneration is also induced in response to injury. Precise control of this cyclic regeneration process is essential for maintaining the homeostasis of living organisms. While stem cells are regulated by the intra-follicle-adjacent micro-environmental niche, this niche is also modulated dynamically by extra-follicular macro-environmental signals, allowing stem cells to adapt to a larger changing environment and physiological needs. Here we review several examples of macro-environments that communicate with the follicles: intradermal adipose tissue, innate immune system, sex hormones, aging, circadian rhythm and seasonal rhythms. Related diseases are also discussed. Unveiling the mechanisms of how stem cell niches are modulated provides clues for regenerative medicine. Given that stem cells are hard to manipulate, focusing translational therapeutic applications at the environments appears to be a more practical approach.

  3. Differential Expression of Stem Cell Markers and Vascular Endothelial Growth Factor in Human Retinoblastoma Tissue

    PubMed Central

    Kim, Martha; Kim, Jeong Hun; Kim, Jin Hyoung; Kim, Dong Hun

    2010-01-01

    Purpose To investigate the relationship between vascular endothelial growth factor (VEGF) and the cancer stem cell-vascular niche complex in human retinoblastoma tissue. Methods Six human retinoblastoma specimens primarily enucleated for Reese-Ellsworth classification stage 5a were stained to detect cancer stem cell markers, including ABCG2 for the stem cell marker and MCM2 for the neural stem cell marker, as well as to detect VEGF for the angiogenic cytokine. Using immunofluorescence, the expression of these proteins was analyzed, and their relative locations noted. Results In non-neoplastic retina of tumor-bearing eyes, ABCG2 and MCM2 were sporadically expressed in the ganglion cell layer and the inner nuclear layer, whereas VEGF was sporadically expressed in inner retina where retinal vessels are abundantly distributed. In the tumor, ABCG2 was strongly expressed out of Wintersteiner rosettes, whereas MCM2 and VEGF were strongly stained in the rosettes. Interestingly, the outer portion of the rosettes was positive for MCM2, and the inner portion of the rosettes was positive for VEGF. Conclusions Our data demonstrated that MCM2 and VEGF are strongly expressed in the rosettes of the tumor, which were far from the area of ABCG2-positive cells. Although VEGF might not directly contribute to the cancer stem cell-vascular niche complex, it could play some role in the differentiation of tumor cells to build up the rosettes. PMID:20157412

  4. Stem cell therapy and tissue engineering for correction of congenital heart disease

    PubMed Central

    Avolio, Elisa; Caputo, Massimo; Madeddu, Paolo

    2015-01-01

    This review article reports on the new field of stem cell therapy and tissue engineering and its potential on the management of congenital heart disease. To date, stem cell therapy has mainly focused on treatment of ischemic heart disease and heart failure, with initial indication of safety and mild-to-moderate efficacy. Preclinical studies and initial clinical trials suggest that the approach could be uniquely suited for the correction of congenital defects of the heart. The basic concept is to create living material made by cellularized grafts that, once implanted into the heart, grows and remodels in parallel with the recipient organ. This would make a substantial improvement in current clinical management, which often requires repeated surgical corrections for failure of implanted grafts. Different types of stem cells have been considered and the identification of specific cardiac stem cells within the heterogeneous population of mesenchymal and stromal cells offers opportunities for de novo cardiomyogenesis. In addition, endothelial cells and vascular progenitors, including cells with pericyte characteristics, may be necessary to generate efficiently perfused grafts. The implementation of current surgical grafts by stem cell engineering could address the unmet clinical needs of patients with congenital heart defects. PMID:26176009

  5. Spontaneous aneuploidy and clone formation in adipose tissue stem cells during different periods of culturing.

    PubMed

    Buyanovskaya, O A; Kuleshov, N P; Nikitina, V A; Voronina, E S; Katosova, L D; Bochkov, N P

    2009-07-01

    Cytogenetic analysis of 13 mesenchymal stem cell cultures isolated from normal human adipose tissue was carried out at different stages of culturing. The incidence of chromosomes 6, 8, 11, and X aneuploidy and polyploidy was studied by fluorescent in situ hybridization. During the early passages, monosomal cells were more often detected than trisomal ones. A clone with chromosome 6 monosomy was detected in three cultures during late passages.

  6. Dental pulp stem cells express tendon markers under mechanical loading and are a potential cell source for tissue engineering of tendon-like tissue.

    PubMed

    Chen, Yu-Ying; He, Sheng-Teng; Yan, Fu-Hua; Zhou, Peng-Fei; Luo, Kai; Zhang, Yan-Ding; Xiao, Yin; Lin, Min-Kui

    2016-12-16

    Postnatal mesenchymal stem cells have the capacity to differentiate into multiple cell lineages. This study explored the possibility of dental pulp stem cells (DPSCs) for potential application in tendon tissue engineering. The expression of tendon-related markers such as scleraxis, tenascin-C, tenomodulin, eye absent homologue 2, collagens I and VI was detected in dental pulp tissue. Interestingly, under mechanical stimulation, these tendon-related markers were significantly enhanced when DPSCs were seeded in aligned polyglycolic acid (PGA) fibre scaffolds. Furthermore, mature tendon-like tissue was formed after transplantation of DPSC-PGA constructs under mechanical loading conditions in a mouse model. This study demonstrates that DPSCs could be a potential stem cell source for tissue engineering of tendon-like tissue.

  7. Dental pulp stem cells express tendon markers under mechanical loading and are a potential cell source for tissue engineering of tendon-like tissue

    PubMed Central

    Chen, Yu-Ying; He, Sheng-Teng; Yan, Fu-Hua; Zhou, Peng-Fei; Luo, Kai; Zhang, Yan-Ding; Xiao, Yin; Lin, Min-Kui

    2016-01-01

    Postnatal mesenchymal stem cells have the capacity to differentiate into multiple cell lineages. This study explored the possibility of dental pulp stem cells (DPSCs) for potential application in tendon tissue engineering. The expression of tendon-related markers such as scleraxis, tenascin-C, tenomodulin, eye absent homologue 2, collagens I and VI was detected in dental pulp tissue. Interestingly, under mechanical stimulation, these tendon-related markers were significantly enhanced when DPSCs were seeded in aligned polyglycolic acid (PGA) fibre scaffolds. Furthermore, mature tendon-like tissue was formed after transplantation of DPSC-PGA constructs under mechanical loading conditions in a mouse model. This study demonstrates that DPSCs could be a potential stem cell source for tissue engineering of tendon-like tissue. PMID:27811845

  8. [Stem cells in adult retina--current state of research, future therapeutic prospects].

    PubMed

    Machalińska, Anna; Zuba-Surma, Ewa K

    2009-01-01

    The latest research reports revealed the presence of stem/progenitor cells located in different regions of matured eye. They are able to differentiate into retinal pigment epithelium cells as well as neural structure of retina. These cells were identified in neurosensory retina, pigment epithelium and within cilliary body and iris epithelium. Moreover, it has been proved that Muller glia possess the potential of differentiation into retinal cells. These findings indicate the presence of potential mechanisms enabling retinal cell repopulation and retinal tissue regeneration. In the present work, the recent reports documenting the presence of different stem cell populations in eye have been reviewed, particularly focusing on recently identified very small embryonic-like stem cells (VSEL-SCs). The potential clinical applications of the residing stem cells and limitations of such therapeutic strategies have been also discussed.

  9. A Scanning Transmission Electron Microscopy (STEM) Approach to Analyzing Large Volumes of Tissue to Detect Nanoparticles

    PubMed Central

    Kempen, Paul J.; Thakor, Avnesh S.; Zavaleta, Cristina; Gambhir, Sanjiv S.; Sinclair, Robert

    2013-01-01

    The use of nanoparticles for the diagnosis and treatment of cancer requires the complete characterization of their toxicity, including accurately locating them within biological tissues. Owing to their size, traditional light microscopy techniques are unable to resolve them. Transmission electron microscopy provides the necessary spatial resolution to image individual nanoparticles in tissue but is severely limited by the very small analysis volume, usually on the order of tens of cubic microns. In this work we developed a scanning transmission electron microscopy (STEM) approach to analyze large volumes of tissue for the presence of polyethylene glycol coated Raman-active-silica-gold-nanoparticles (PEG-R-Si-Au-NPs). This approach utilizes the simultaneous bright and dark field imaging capabilities of STEM along with careful control of the image contrast settings to readily identify PEG-R-Si-Au-NPs in mouse liver tissue without the need for additional time consuming analytical characterization. We utilized this technique to analyze 243,000 µm3 of mouse liver tissue for the presence of PEG-R-Si-Au-NPs. Nanoparticles injected into the mice intravenously via the tail-vein accumulated in the liver while those injected intrarectally did not, indicating that they remain in the colon and do not pass through the colon wall into the systemic circulation. PMID:23803218

  10. Application of induced pluripotent stem (iPS) cells in periodontal tissue regeneration.

    PubMed

    Duan, Xuejing; Tu, Qisheng; Zhang, Jin; Ye, Jinhai; Sommer, Cesar; Mostoslavsky, Gustavo; Kaplan, David; Yang, Pishan; Chen, Jake

    2011-01-01

    Tissue engineering provides a new paradigm for periodontal tissue regeneration in which proper stem cells and effective cellular factors are very important. The objective of this study was, for the first time, to investigate the capabilities and advantages of periodontal tissue regeneration using induced pluripotent stem (iPS) cells and enamel matrix derivatives (EMD). In this study the effect of EMD gel on iPS cells in vitro was first determined, and then tissue engineering technique was performed to repair periodontal defects in three groups: silk scaffold only; silk scaffold + EMD; and silk scaffold + EMD + iPS cells. EMD greatly enhanced the mRNA expression of Runx2 but inhibited the mRNA expression of OC and mineralization nodule formation in vitro. Transplantation of iPS cells showed higher expression levels of OC, Osx, and Runx2 genes, both 12 and 24 days postsurgery. At 24 days postsurgery in the iPS cell group, histological analysis showed much more new alveolar bone and cementum formation with regenerated periodontal ligament between them. The results showed the commitment role that EMD contributes in mesenchymal progenitors to early cells in the osteogenic lineage. iPS cells combined with EMD provide a valuable tool for periodontal tissue engineering, by promoting the formation of new cementum, alveolar bone, and normal periodontal ligament.

  11. Electrospinning adipose tissue-derived extracellular matrix for adipose stem cell culture.

    PubMed

    Francis, Michael P; Sachs, Patrick C; Madurantakam, Parthasarathy A; Sell, Scott A; Elmore, Lynne W; Bowlin, Gary L; Holt, Shawn E

    2012-07-01

    Basement membrane-rich extracellular matrices, particularly murine sarcoma-derived Matrigel, play important roles in regenerative medicine research, exhibiting marked cellular responses in vitro and in vivo, although with limited clinical applications. We find that a human-derived matrix from lipoaspirate fat, a tissue rich in basement membrane components, can be fabricated by electrospinning and used to support cell culture. We describe practical applications and purification of extracellular matrix (ECM) from adipose tissue (At-ECM) and its use in electrospinning scaffolds and adipose stem cell (ASC) culture. The matrix composition of this purified and electrospun At-ECM was assessed histochemically for basement membrane, connective tissue, collagen, elastic fibers/elastin, glycoprotein, and proteoglycans. Each histochemical stain was positive in fat tissue, purified At-ECM, and electrospun At-ECM, and to some extent positive in a 10:90 blend with polydioxanone (PDO). We also show that electrospun At-ECM, alone and blended with PDO, supports ASC attachment and growth, suggesting that electrospun At-ECM scaffolds support ASC cultivation. These studies show that At-ECM can be isolated and electrospun as a basement membrane-rich tissue engineering matrix capable of supporting stem cells, providing the groundwork for an array of future regenerative medicine advances.

  12. [Application Prospect of Stem Cell-derived Microvesicles in Regeneration of Injured Tissues].

    PubMed

    Yin, Huiqun; Jiang, Hong

    2015-06-01

    More and more evidence indicates that microvesicles (MVs) play a key role in cell-to-cell communication. The MVs are circular fragments of membrane released from the endosomal compartment as exosomes or shed from the cell surface membranes of most types. Components of donor cells are incorporated into MVs that contain bioactive lipids, proteins, genetic cargoes. MVs derived from stem cells may reprogram cells that survived in injury tissue and favor tissue regeneration by delivering their bioactive cargoes to influence the behaviors of recipient cells. Compared with mesenchymal stem cells (MSCs), MVs derived from MSCs were found to mimic the beneficial effects of these cells. These proregenerative effects mediated by MVs can be explained by the fact that MVs are enriched in bioactive lipids, anti-apoptotic and pro-stimulatory growth factors or cytokines, and deliver mRNAs, regulatory miRNAs and proteins that improve overall cell function. Therefore, it opens novel perspectives in exploiting these MVs in tissue regeneration and repair. In addition, the use of MVs instead of stem cells could represent a safe and potentially more advantageous alternative to cell-therapy approaches.

  13. Isolation and characterisation of mesenchymal stem cells derived from human placenta tissue

    PubMed Central

    Vellasamy, Shalini; Sandrasaigaran, Pratheep; Vidyadaran, Sharmili; George, Elizabeth; Ramasamy, Rajesh

    2012-01-01

    AIM: To explore the feasibility of placenta tissue as a reliable and efficient source for generating mesenchymal stem cells (MSC). METHODS: MSC were generated from human placenta tissue by enzymatic digestion and mechanical dissociation. The placenta MSC (PLC-MSC) were characterized for expression of cell surface markers, embryonic stem cell (ECS) gene expression and their differentiation ability into adipocytes and osteocytes. The immunosuppressive properties of PLC-MSC on resting and phytohemagglutinin (PHA) stimulated allogenic T cells were assessed by means of cell proliferation via incorporation of tritium thymidine (3H-TdR). RESULTS: The generated PLC-MSC appeared as spindle-shaped cells, expressed common MSC surface markers and ESC transcriptional factors. They also differentiated into adipogenic and osteogenic lineages when induced. However, continuous cultivation up to passage 15 caused changes in morphological appearance and cellular senescence, although the stem cell nature of their protein expression was unchanged. In terms of their immunosuppressive properties, PLC-MSC were unable to stimulate resting T cell proliferation; they inhibited the PHA stimulated T cells in a dose dependent manner through cell to cell contact. In our study, MSC generated from human placenta exhibited similar mesenchymal cell surface markers; MSC-like gene expression pattern and MSC-like differentiation potential were comparable to other sources of MSC. CONCLUSION: We suggest that placenta tissues can serve as an alternative source of MSC for future experimental and clinical studies. PMID:22993662

  14. Micropatterning control of tubular commitment in human adult renal stem cells.

    PubMed

    Sciancalepore, Anna G; Portone, Alberto; Moffa, Maria; Persano, Luana; De Luca, Maria; Paiano, Aurora; Sallustio, Fabio; Schena, Francesco P; Bucci, Cecilia; Pisignano, Dario

    2016-07-01

    The treatment of renal injury by autologous, patient-specific adult stem cells is still an unmet need. Unsolved issues remain the spatial integration of stem cells into damaged areas of the organ, the commitment in the required cell type and the development of improved bioengineered devices. In this respect, biomaterials and architectures have to be specialized to control stem cell differentiation. Here, we perform an extensive study on micropatterned extracellular matrix proteins, which constitute a simple and non-invasive approach to drive the differentiation of adult renal progenitor/stem cells (ARPCs) from human donors. ARPCs are interfaced with fibronectin (FN) micropatterns, in the absence of exogenous chemicals or cellular reprogramming. We obtain the differentiation towards tubular cells of ARPCs cultured in basal medium conditions, the tubular commitment thus being specifically induced by micropatterned substrates. We characterize the stability of the tubular differentiation as well as the induction of a polarized phenotype in micropatterned ARPCs. Thus, the developed cues, driving the functional commitment of ARPCs, offer a route to recreate the microenvironment of the stem cell niche in vitro, that may serve, in perspective, for the development of ARPC-based bioengineered devices.

  15. Mechanical modulation of nascent stem cell lineage commitment in tissue engineering scaffolds.

    PubMed

    Song, Min Jae; Dean, David; Knothe Tate, Melissa L

    2013-07-01

    Taking inspiration from tissue morphogenesis in utero, this study tests the concept of using tissue engineering scaffolds as delivery devices to modulate emergent structure-function relationships at early stages of tissue genesis. We report on the use of a combined computational fluid dynamics (CFD) modeling, advanced manufacturing methods, and experimental fluid mechanics (micro-piv and strain mapping) for the prospective design of tissue engineering scaffold geometries that deliver spatially resolved mechanical cues to stem cells seeded within. When subjected to a constant magnitude global flow regime, the local scaffold geometry dictates the magnitudes of mechanical stresses and strains experienced by a given cell, and in a spatially resolved fashion, similar to patterning during morphogenesis. In addition, early markers of mesenchymal stem cell lineage commitment relate significantly to the local mechanical environment of the cell. Finally, by plotting the range of stress-strain states for all data corresponding to nascent cell lineage commitment (95% CI), we begin to "map the mechanome", defining stress-strain states most conducive to targeted cell fates. In sum, we provide a library of reference mechanical cues that can be delivered to cells seeded on tissue engineering scaffolds to guide target tissue phenotypes in a temporally and spatially resolved manner. Knowledge of these effects allows for prospective scaffold design optimization using virtual models prior to prototyping and clinical implementation. Finally, this approach enables the development of next generation scaffolds cum delivery devices for genesis of complex tissues with heterogenous properties, e.g., organs, joints or interface tissues such as growth plates.

  16. Inflammatory cues acting on the adult intestinal stem cells and the early onset of cancer (Review)

    PubMed Central

    DE LERMA BARBARO, A.; PERLETTI, G.; BONAPACE, I.M.; MONTI, E.

    2014-01-01

    The observation that cancer often arises at sites of chronic inflammation has prompted the idea that carcinogenesis and inflammation are deeply interwoven. In fact, the current literature highlights a role for chronic inflammation in virtually all the steps of carcinogenesis, including tumor initiation, promotion and progression. The aim of the present article is to review the current literature on the involvement of chronic inflammation in the initiation step and in the very early phases of tumorigenesis, in a type of cancer where adult stem cells are assumed to be the cells of origin of neoplasia. Since the gastrointestinal tract is regarded as the best-established model system to address the liaison between chronic inflammation and neoplasia, the focus of this article will be on intestinal cancer. In fact, the anatomy of the intestinal epithelial lining is uniquely suited to study adult stem cells in their niche, and the bowel crypt is an ideal developmental biology system, as proliferation, differentiation and cell migration are all distributed linearly along the long axis of the crypt. Moreover, crypt stem cells are regarded today as the most likely targets of neoplastic transformation in bowel cancer. More specifically, the present review addresses the molecular mechanisms whereby a state of chronic inflammation could trigger the neoplastic process in the intestine, focusing on the generation of inflammatory cues evoking enhanced proliferation in cells not initiated but at risk of neoplastic transformation because of their stemness. Novel experimental approaches, based on triggering an inflammatory stimulus in the neighbourhood of adult intestinal stem cells, are warranted to address some as yet unanswered questions. A possible approach, the targeted transgenesis of Paneth cells, may be aimed at ‘hijacking’ the crypt stem cell niche from a status characterized by the maintenance of homeostasis to local chronic inflammation, with the prospect of initiating

  17. Human induced pluripotent stem cell-derived beating cardiac tissues on paper.

    PubMed

    Wang, Li; Xu, Cong; Zhu, Yujuan; Yu, Yue; Sun, Ning; Zhang, Xiaoqing; Feng, Ke; Qin, Jianhua

    2015-11-21

    There is a growing interest in using paper as a biomaterial scaffold for cell-based applications. In this study, we made the first attempt to fabricate a paper-based array for the culture, proliferation, and direct differentiation of human induced pluripotent stem cells (hiPSCs) into functional beating cardiac tissues and create "a beating heart on paper." This array was simply constructed by binding a cured multi-well polydimethylsiloxane (PDMS) mold with common, commercially available paper substrates. Three types of paper material (print paper, chromatography paper and nitrocellulose membrane) were tested for adhesion, proliferation and differentiation of human-derived iPSCs. We found that hiPSCs grew well on these paper substrates, presenting a three-dimensional (3D)-like morphology with a pluripotent property. The direct differentiation of human iPSCs into functional cardiac tissues on paper was also achieved using our modified differentiation approach. The cardiac tissue retained its functional activities on the coated print paper and chromatography paper with a beating frequency of 40-70 beats per min for up to three months. Interestingly, human iPSCs could be differentiated into retinal pigment epithelium on nitrocellulose membrane under the conditions of cardiac-specific induction, indicating the potential roles of material properties and mechanical cues that are involved in regulating stem cell differentiation. Taken together, these results suggest that different grades of paper could offer great opportunities as bioactive, low-cost, and 3D in vitro platforms for stem cell-based high-throughput drug testing at the tissue/organ level and for tissue engineering applications.

  18. Epidermal stem cells and their epigenetic regulation.

    PubMed

    Shen, Qi; Jin, Hongchuan; Wang, Xian

    2013-08-30

    Stem cells play an essential role in embryonic development, cell differentiation and tissue regeneration. Tissue homeostasis in adults is maintained by adult stem cells resident in the niches of different tissues. As one kind of adult stem cell, epidermal stem cells have the potential to generate diversified types of progeny cells in the skin. Although its biology is still largely unclarified, epidermal stem cells are widely used in stem cell research and regenerative medicine given its easy accessibility and pluripotency. Despite the same genome, cells within an organism have different fates due to the epigenetic regulation of gene expression. In this review, we will briefly discuss the current understanding of epigenetic modulation in epidermal stem cells.

  19. Quiescent adult neural stem cells are exceptionally sensitive to cosmic radiation

    PubMed Central

    Encinas, Juan M.; Vazquez, Marcelo E.; Switzer, Robert C.; Chamberland, Dennis W.; Nick, Harry; Levine, Howard G.; Scarpa, Philip J.; Enikolopov, Grigori; Steindler, Dennis A.

    2012-01-01

    Generation of new neurons in the adult brain, a process that is likely to be essential for learning, memory, and mood regulation, is impaired by radiation. Therefore, radiation exposure might have not only such previously expected consequences as increased probability of developing cancer, but might also impair cognitive function and emotional stability. Radiation exposure is encountered in settings ranging from cancer therapy to space travel; evaluating the neurogenic risks of radiation requires identifying the at-risk populations of stem and progenitor cells in the adult brain. Here we have used a novel reporter mouse line to find that early neural progenitors are selectively affected by conditions simulating the space radiation environment. This is reflected both in a decrease in the number of these progenitors in the neurogenic regions and in an increase in the number of dying cells in these regions. Unexpectedly, we found that quiescent neural stem cells, rather than their rapidly dividing progeny, are most sensitive to radiation. Since these stem cells are responsible for adult neurogenesis, their death would have a profound impact on the production of new neurons in the irradiated adult brain. Our finding raises an important concern about cognitive and emotional risks associated with radiation exposure. PMID:18076878

  20. Empowering Adult Stem Cells for Myocardial Regeneration V2.0: Success in Small Steps.

    PubMed

    Broughton, Kathleen M; Sussman, Mark A

    2016-03-04

    Much has changed since our survey of the landscape for myocardial regeneration powered by adult stem cells 4 years ago.(1) The intervening years since that first review has witnessed an explosive expansion of studies that advance both understanding and implementation of adult stem cells in promoting myocardial repair. Painstaking research from innumerable laboratories throughout the world is prying open doors that may lead to restoration of myocardial structure and function in the wake of pathological injury. This global effort has produced deeper mechanistic comprehension coupled with an evolving appreciation for the complexity of myocardial regeneration in the adult context. Undaunted by both known and (as yet) unknown challenges, pursuit of myocardial regenerative medicine mediated by adult stem cell therapy has gathered momentum fueled by tantalizing clues and visionary goals. This concise review takes a somewhat different perspective than our initial treatise, taking stock of the business sector that has become an integral part of the field while concurrently updating state of affairs in cutting edge research. Looking retrospectively at advancement over the years as all reviews eventually must, the fundamental lesson to be learned is best explained by Jonatan Mårtensson: "Success will never be a big step in the future. Success is a small step taken just now."

  1. Myf5 haploinsufficiency reveals distinct cell fate potentials for adult skeletal muscle stem cells.

    PubMed

    Gayraud-Morel, Barbara; Chrétien, Fabrice; Jory, Aurélie; Sambasivan, Ramkumar; Negroni, Elisa; Flamant, Patricia; Soubigou, Guillaume; Coppée, Jean-Yves; Di Santo, James; Cumano, Ana; Mouly, Vincent; Tajbakhsh, Shahragim

    2012-04-01

    Skeletal muscle stem cell fate in adult mice is regulated by crucial transcription factors, including the determination genes Myf5 and Myod. The precise role of Myf5 in regulating quiescent muscle stem cells has remained elusive. Here we show that most, but not all, quiescent satellite cells express Myf5 protein, but at varying levels, and that resident Myf5 heterozygous muscle stem cells are more primed for myogenic commitment compared with wild-type satellite cells. Paradoxically however, heterotypic transplantation of Myf5 heterozygous cells into regenerating muscles results in higher self-renewal capacity compared with wild-type stem cells, whereas myofibre regenerative capacity is not altered. By contrast, Pax7 haploinsufficiency does not show major modifications by transcriptome analysis. These observations provide a mechanism linking Myf5 levels to muscle stem cell heterogeneity and fate by exposing two distinct and opposing phenotypes associated with Myf5 haploinsufficiency. These findings have important implications for how stem cell fates can be modulated by crucial transcription factors while generating a pool of responsive heterogeneous cells.

  2. Isolation and myogenic differentiation of mesenchymal stem cells for urologic tissue engineering.

    PubMed

    Wu, Rongpei; Liu, Guihua; Bharadwaj, Shantaram; Zhang, Yuanyuan

    2013-01-01

    Cell-based tissue engineering is one of the most promising areas in biotechnology for restoring tissues and organ function in the urinary tract. Current strategies for bladder tissue engineering require a competent biological scaffold that is seeded in vitro with the patient's own bladder cells. This use of autologous cells avoids graft rejection and the long-term use of immunosuppressive medications usually required after allogeneic transplantation. However, suitable bladder cells from the patient are sometimes limited or unobtainable. When suitable cells are unavailable for seeding due to bladder exstrophy, malignancy, or other reasons, the use of other cell types originating from the patient may be an alternative. A suitable alternative to autologous bladder cells could be mesenchymal stem cells (MSC). MSC reside primarily in the bone marrow, although they exist in other sites as well, including adipose tissue, peripheral and cord blood, liver tissue, and fetal tissues. Bone marrow-derived stromal cell populations contain few MSC (one MSC in 10(4)-5 × 10(7) marrow cells), with the exact number depending on the age of the patient. Despite their limited numbers, MSC possess both the ability to self-renew for extended periods of time and the potential to differentiate into several different specialized cell types under the appropriate conditions. MSC are capable of expansion and tissue-specific differentiation in vitro based on external signals and/or the environment. There are different methodologies for induction and maintenance of a differentiated cell phenotype from MSC. For example, MSC can differentiate into a smooth muscle cell (SMC) phenotype in vitro when exposed to stimuli such as conditioned medium derived from SMC cultures or specific myogenic growth factors (PDGF-BB, HGF, TGF-β). These differential cells can migrate to a scaffold for differentiation into smooth muscle-like cells in vivo. Furthermore, stem cell-seeded scaffolds that are implanted into

  3. Novel Adult Stem Cells for Peripheral Nerve Regeneration

    DTIC Science & Technology

    2013-09-01

    Symposium on Vascular Tissue Engineering. Holland, 5/2013 o The Joint British Society for Cardiovascular Research/British Atherosclerosis Society meeting... atherosclerosis , involves proliferation and migration of vascular cells1–4. Vascular smooth muscle cells (SMCs) are the predominant cell type in the tunica media...osteogenic cells in diseased vessels remains to be tested using atherosclerosis models. The identification of MVSC in human arteries makes MVSC a

  4. Stem cells: classifications, controversies, and clinical applications.

    PubMed

    Fortier, Lisa A

    2005-01-01

    The application of stem cells in regenerative and reparative therapies is emerging in surgery. Published information can lead to an over simplified view of stem cells with respect to their definitions, tissues of origin, abilities to differentiate into tissue lineages, and their capacity for functional tissue regeneration. The goals of this review article are to define embryonic and adult stem cells, compare differences between them, and summarize their potential clinical applications.

  5. Perivascular Stem Cells at the Tip of Mouse Incisors Regulate Tissue Regeneration.

    PubMed

    Pang, Yvonne Wy; Feng, Jifan; Daltoe, Felipe; Fatscher, Robert; Gentleman, Eileen; Gentleman, Molly M; Sharpe, Paul T

    2016-03-01

    Cells with in vitro properties similar to those of bone marrow stromal stem cells are present in tooth pulp as quiescent cells that are mobilized by damage. These dental pulp stem cells (DPSCs) respond to damage by stimulating proliferation and differentiation into odontoblast-like cells that form dentine to repair the damage. In continuously growing mouse incisors, tissue at the incisor tips is continuously being damaged by the shearing action between the upper and lower teeth acting to self-sharpen the tips. We investigated mouse incisor tips as a model for the role of DPSCs in a continuous natural repair/regeneration process. We show that the pulp at the incisor tip is composed of a disorganized mass of mineralized tissue produced by odontoblast-like cells. These cells become embedded into the mineralized tissue that is rapidly formed and then lost during feeding. Tetracycline labeling not only revealed the expected incorporation into newly synthesized dentine formation of the incisor but also a zone covering the pulp cavity at the tips of the incisors that is mineralized very rapidly. This tissue was dentine-like but had a significantly lower mineral content than dentine as determined by Raman spectroscopy. The mineral was more crystalline than dentine, indicative of small, defect-free mineral particles. To identify the origin of cells responsible for deposition of this mineralized tissue, we genetically labeled perivascular cells by crossing NG2(ERT2) Cre and Nestin Cre mice with reporter mice. A large number of pericyte-derived cells were visible in the pulp of incisor tips with some having elongated, odontoblast-like shapes. These results show that in mouse incisors, rapid, continuous mineralization occurs at the tip to seal off the pulp tissue from the external environment. The mineral is formed by perivascular-derived cells that differentiate into cells expressing dentin sialo-phosphoprotein (DSPP) and produce a dentine-like material in a process that

  6. Encapsulated dental-derived mesenchymal stem cells in an injectable and biodegradable scaffold for applications in bone tissue engineering.

    PubMed

    Moshaverinia, Alireza; Chen, Chider; Akiyama, Kentaro; Xu, Xingtian; Chee, Winston W L; Schricker, Scott R; Shi, Songtao

    2013-11-01

    Bone grafts are currently the major family of treatment options in modern reconstructive dentistry. As an alternative, stem cell-scaffold constructs seem to hold promise for bone tissue engineering. However, the feasibility of encapsulating dental-derived mesenchymal stem cells in scaffold biomaterials such as alginate hydrogel remains to be tested. The objectives of this study were, therefore, to: (1) develop an injectable scaffold based on oxidized alginate microbeads encapsulating periodontal ligament stem cells (PDLSCs) and gingival mesenchymal stem cells (GMSCs); and (2) investigate the cell viability and osteogenic differentiation of the stem cells in the microbeads both in vitro and in vivo. Microbeads with diameters of 1 ± 0.1 mm were fabricated with 2 × 10(6) stem cells/mL of alginate. Microbeads containing PDLSCs, GMSCs, and human bone marrow mesenchymal stem cells as a positive control were implanted subcutaneously and ectopic bone formation was analyzed by micro CT and histological analysis at 8-weeks postimplantation. The encapsulated stem cells remained viable after 4 weeks of culturing in osteo-differentiating induction medium. Scanning electron microscopy and X-ray diffraction results confirmed that apatitic mineral was deposited by the stem cells. In vivo, ectopic mineralization was observed inside and around the implanted microbeads containing the immobilized stem cells. These findings demonstrate for the first time that immobilization of PDLSCs and GMSCs in alginate microbeads provides a promising strategy for bone tissue engineering.

  7. Identification of Reference Genes for RT-qPCR Data Normalization in Cannabis sativa Stem Tissues

    PubMed Central

    Mangeot-Peter, Lauralie; Legay, Sylvain; Hausman, Jean-Francois; Esposito, Sergio; Guerriero, Gea

    2016-01-01

    Gene expression profiling via quantitative real-time PCR is a robust technique widely used in the life sciences to compare gene expression patterns in, e.g., different tissues, growth conditions, or after specific treatments. In the field of plant science, real-time PCR is the gold standard to study the dynamics of gene expression and is used to validate the results generated with high throughput techniques, e.g., RNA-Seq. An accurate relative quantification of gene expression relies on the identification of appropriate reference genes, that need to be determined for each experimental set-up used and plant tissue studied. Here, we identify suitable reference genes for expression profiling in stems of textile hemp (Cannabis sativa L.), whose tissues (isolated bast fibres and core) are characterized by remarkable differences in cell wall composition. We additionally validate the reference genes by analysing the expression of putative candidates involved in the non-oxidative phase of the pentose phosphate pathway and in the first step of the shikimate pathway. The goal is to describe the possible regulation pattern of some genes involved in the provision of the precursors needed for lignin biosynthesis in the different hemp stem tissues. The results here shown are useful to design future studies focused on gene expression analyses in hemp. PMID:27649158

  8. Adipose stem cells used to reconstruct 13 cases with cranio-maxillofacial hard-tissue defects.

    PubMed

    Sándor, George K; Numminen, Jura; Wolff, Jan; Thesleff, Tuomo; Miettinen, Aimo; Tuovinen, Veikko J; Mannerström, Bettina; Patrikoski, Mimmi; Seppänen, Riitta; Miettinen, Susanna; Rautiainen, Markus; Öhman, Juha

    2014-04-01

    Although isolated reports of hard-tissue reconstruction in the cranio-maxillofacial skeleton exist, multipatient case series are lacking. This study aimed to review the experience with 13 consecutive cases of cranio-maxillofacial hard-tissue defects at four anatomically different sites, namely frontal sinus (3 cases), cranial bone (5 cases), mandible (3 cases), and nasal septum (2 cases). Autologous adipose tissue was harvested from the anterior abdominal wall, and adipose-derived stem cells were cultured, expanded, and then seeded onto resorbable scaffold materials for subsequent reimplantation into hard-tissue defects. The defects were reconstructed with either bioactive glass or β-tricalcium phosphate scaffolds seeded with adipose-derived stem cells (ASCs), and in some cases with the addition of recombinant human bone morphogenetic protein-2. Production and use of ASCs were done according to good manufacturing practice guidelines. Follow-up time ranged from 12 to 52 months. Successful integration of the construct to the surrounding skeleton was noted in 10 of the 13 cases. Two cranial defect cases in which nonrigid resorbable containment meshes were used sustained bone resorption to the point that they required the procedure to be redone. One septal perforation case failed outright at 1 year because of the postsurgical resumption of the patient's uncontrolled nasal picking habit.

  9. Adipose Stem Cells Used to Reconstruct 13 Cases With Cranio-Maxillofacial Hard-Tissue Defects

    PubMed Central

    Numminen, Jura; Wolff, Jan; Thesleff, Tuomo; Miettinen, Aimo; Tuovinen, Veikko J.; Mannerström, Bettina; Patrikoski, Mimmi; Seppänen, Riitta; Miettinen, Susanna; Rautiainen, Markus; Öhman, Juha

    2014-01-01

    Although isolated reports of hard-tissue reconstruction in the cranio-maxillofacial skeleton exist, multipatient case series are lacking. This study aimed to review the experience with 13 consecutive cases of cranio-maxillofacial hard-tissue defects at four anatomically different sites, namely frontal sinus (3 cases), cranial bone (5 cases), mandible (3 cases), and nasal septum (2 cases). Autologous adipose tissue was harvested from the anterior abdominal wall, and adipose-derived stem cells were cultured, expanded, and then seeded onto resorbable scaffold materials for subsequent reimplantation into hard-tissue defects. The defects were reconstructed with either bioactive glass or β-tricalcium phosphate scaffolds seeded with adipose-derived stem cells (ASCs), and in some cases with the addition of recombinant human bone morphogenetic protein-2. Production and use of ASCs were done according to good manufacturing practice guidelines. Follow-up time ranged from 12 to 52 months. Successful integration of the construct to the surrounding skeleton was noted in 10 of the 13 cases. Two cranial defect cases in which nonrigid resorbable containment meshes were used sustained bone resorption to the point that they required the procedure to be redone. One septal perforation case failed outright at 1 year because of the postsurgical resumption of the patient’s uncontrolled nasal picking habit. PMID:24558162

  10. Phasor FLIM metabolic mapping of stem cells and cancer cells in live tissues

    NASA Astrophysics Data System (ADS)

    Stringari, Chiara; Donovan, Peter; Gratton, Enrico

    2012-03-01

    We use the phasor approach to fluorescence lifetime imaging and intrinsic biochemical fluorescence biomarkers in conjunction with image segmentation and the concept of cell phasor for deriving metabolic maps of cells and living tissues in vivo. In issues we identify and separate intrinsic fluorophores such as collagen, retinol, retinoic acid, porphyrin, flavins, free and bound nicotinamide adenine dinucleotide (NADH). Metabolic signatures of tissues are obtained by calculating the phasor fingerprint of single cells and by mapping the relative concentration of metabolites. This method detects small changes in metabolic signatures and redox states of cells. Phasor fingerprints of stem cells cluster according to their differentiation state in a living tissue such as the C. elegans germ line and the crypt base of small intestine and colon. Phasor FLIM provides a label-free and fit-free sensitive method to identify metabolic states of cells and to classify stem cells, normal differentiated cells and cancer cells both in vitro and in a live tissue. Our method could identify symmetric and asymmetric divisions, predict cell fate and identify pre-cancer stages in vivo. This method is a promising non-invasive optical tool for monitoring metabolic pathways during differentiation and carcinogenesis, for cell sorting and high throughput screening.

  11. Adipose mesenchymal stem cells in the field of bone tissue engineering

    PubMed Central

    Romagnoli, Cecilia; Brandi, Maria Luisa

    2014-01-01

    Bone tissue engineering represents one of the most challenging emergent fields for scientists and clinicians. Current failures of autografts and allografts in many pathological conditions have prompted researchers to find new biomaterials able to promote bone repair or regeneration with specific characteristics of biocompatibility, biodegradability and osteoinductivity. Recent advancements for tissue regeneration in bone defects have occurred by following the diamond concept and combining the use of growth factors and mesenchymal stem cells (MSCs). In particular, a more abundant and easily accessible source of MSCs was recently discovered in adipose tissue. These adipose stem cells (ASCs) can be obtained in large quantities with little donor site morbidity or patient discomfort, in contrast to the invasive and painful isolation of bone marrow MSCs. The osteogenic potential of ASCs on scaffolds has been examined in cell cultures and animal models, with only a few cases reporting the use of ASCs for successful reconstruction or accelerated healing of defects of the skull and jaw in patients. Although these reports extend our limited knowledge concerning the use of ASCs for osseous tissue repair and regeneration, the lack of standardization in applied techniques makes the comparison between studies difficult. Additional clinical trials are needed to assess ASC therapy and address potential ethical and safety concerns, which must be resolved to permit application in regenerative medicine. PMID:24772241

  12. Adipose mesenchymal stem cells in the field of bone tissue engineering.

    PubMed

    Romagnoli, Cecilia; Brandi, Maria Luisa

    2014-04-26

    Bone tissue engineering represents one of the most challenging emergent fields for scientists and clinicians. Current failures of autografts and allografts in many pathological conditions have prompted researchers to find new biomaterials able to promote bone repair or regeneration with specific characteristics of biocompatibility, biodegradability and osteoinductivity. Recent advancements for tissue regeneration in bone defects have occurred by following the diamond concept and combining the use of growth factors and mesenchymal stem cells (MSCs). In particular, a more abundant and easily accessible source of MSCs was recently discovered in adipose tissue. These adipose stem cells (ASCs) can be obtained in large quantities with little donor site morbidity or patient discomfort, in contrast to the invasive and painful isolation of bone marrow MSCs. The osteogenic potential of ASCs on scaffolds has been examined in cell cultures and animal models, with only a few cases reporting the use of ASCs for successful reconstruction or accelerated healing of defects of the skull and jaw in patients. Although these reports extend our limited knowledge concerning the use of ASCs