Detection of homing-in of stem cells labeled with technetium-99m hexamethylpropyleneamine oxime in infarcted myocardium after intracoronary injection

PubMed Central

Patel, Chetan D; Agarwal, Snehlata; Seth, Sandeep; Mohanty, Sujata; Aggarwal, Himesh; Gupta, Namit

2014-01-01

Bone marrow stem cells having myogenic potential are promising candidates for various cell-based therapies for myocardial disease. We present here images showing homing of technetium-99m (Tc-99m) hexamethylpropyleneamine oxime (HMPAO) labeled stem cells in the infarcted myocardium from a pilot study conducted to radio-label part of the stem cells in patients enrolled in a stem cell clinical trial for recent myocardial infarction. PMID:25400375

Stem-Like Cell Characteristics from Breast Milk of Mothers with Preterm Infants as Compared to Mothers with Term Infants.

PubMed

Briere, Carrie-Ellen; Jensen, Todd; McGrath, Jacqueline M; Young, Erin E; Finck, Christine

2017-04-01

Breast milk stem cells are hypothesized to be involved in infant health and development. Our research team is the first known team to enroll mothers of hospitalized preterm infants during the first few weeks of lactation and compare stem cell phenotypes and gene expression to mothers of healthy full-term infants. Participants were recruited from a Level IV Neonatal Intensive Care Unit (preterm dyads) and the community (full-term dyads) in the northeastern United States. Mothers of hospitalized preterm infants (<37 weeks gestational age at birth) and mothers of healthy full-term infants (>39 weeks gestational age at birth). Breast milk stem-like cell populations were identified in both preterm and full-term breast milk samples. The data suggest variability in the proportion of stem cell phenotypes present, as well as statistically significant differential expression (both over- and underexpression) of stem cell-specific genetic markers when comparing mothers' milk for preterm and full-term births. Our findings indicate that (1) stem cells are present in preterm breast milk; (2) differential expression of stem cell-specific markers can be detected in preterm and full-term breast milk samples; and (3) the percentage of cells expressing the various stem cell-specific markers differs when preterm and full-term breast milk samples are compared.

Notch-Dependent Pituitary SOX2+ Stem Cells Exhibit a Timed Functional Extinction in Regulation of the Postnatal Gland

PubMed Central

Zhu, Xiaoyan; Tollkuhn, Jessica; Taylor, Havilah; Rosenfeld, Michael G.

2015-01-01

Summary Although SOX2+ stem cells are present in the postnatal pituitary gland, how they are regulated molecularly and whether they are required for pituitary functions remain unresolved questions. Using a conditional knockout animal model, here we demonstrate that ablation of the canonical Notch signaling in the embryonic pituitary gland leads to progressive depletion of the SOX2+ stem cells and hypoplastic gland. Furthermore, we show that the SOX2+ stem cells initially play a significant role in contributing to postnatal pituitary gland expansion by self-renewal and differentiating into distinct lineages in the immediate postnatal period. However, we found that within several weeks postpartum, the SOX2+ stem cells switch to an essentially dormant state and are no longer required for homeostasis/tissue adaptation. Our results present a dynamic tissue homeostatic model in which stem cells provide an initial contribution to the growth of the neonatal pituitary gland, whereas the mature gland can be maintained in a stem cell-independent fashion. PMID:26651607

Latent progenitor cells as potential regulators for tympanic membrane regeneration

NASA Astrophysics Data System (ADS)

Kim, Seung Won; Kim, Jangho; Seonwoo, Hoon; Jang, Kyung-Jin; Kim, Yeon Ju; Lim, Hye Jin; Lim, Ki-Taek; Tian, Chunjie; Chung, Jong Hoon; Choung, Yun-Hoon

2015-06-01

Tympanic membrane (TM) perforation, in particular chronic otitis media, is one of the most common clinical problems in the world and can present with sensorineural healing loss. Here, we explored an approach for TM regeneration where the latent progenitor or stem cells within TM epithelial layers may play an important regulatory role. We showed that potential TM stem cells present highly positive staining for epithelial stem cell markers in all areas of normal TM tissue. Additionally, they are present at high levels in perforated TMs, especially in proximity to the holes, regardless of acute or chronic status, suggesting that TM stem cells may be a potential factor for TM regeneration. Our study suggests that latent TM stem cells could be potential regulators of regeneration, which provides a new insight into this clinically important process and a potential target for new therapies for chronic otitis media and other eardrum injuries.

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

PubMed

Zulewski, Henryk

2006-10-14

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

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

PubMed

Zulewski, Henryk

2007-03-02

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

Biomaterials and Stem Cells for Tissue Engineering

PubMed Central

Zhang, Zhanpeng; Gupte, Melanie J.; Ma, Peter X.

2013-01-01

Importance of the field Organ failure and tissue loss are challenging health issues due to widespread injury, the lack of organs for transplantation, and limitations of conventional artificial implants. The field of tissue engineering aims to provide alternative living substitutes that restore, maintain or improve tissue function. Areas covered in this review In this paper, a wide range of porous scaffolds are reviewed, with an emphasis on phase separation techniques that generate advantageous nanofibrous 3D scaffolds for stem cell-based tissue engineering applications. In addition, methods for presentation and delivery of bioactive molecules to mimic the properties of stem cell niche are summarized. Recent progress in using these bio-instructive scaffolds to support stem cell differentiation and tissue regeneration is also presented. What the reader will gain Stem cells have great clinical potential because of their capability to differentiate into multiple cell types. Biomaterials have served as artificial extracellular environments to regulate stem cell behavior. Biomaterials with various physical, mechanical, and chemical properties can be designed to control stem cell development for regeneration. Take home message The research at the interface of stem cell biology and biomaterials has made and will continue to make exciting advances in tissue engineering. PMID:23327471

Redox environment in stem and differentiated cells: A quantitative approach.

PubMed

Lyublinskaya, O G; Ivanova, Ju S; Pugovkina, N A; Kozhukharova, I V; Kovaleva, Z V; Shatrova, A N; Aksenov, N D; Zenin, V V; Kaulin, Yu A; Gamaley, I A; Nikolsky, N N

2017-08-01

Stem cells are believed to maintain a specific intracellular redox status through a combination of enhanced removal capacity and limited production of ROS. In the present study, we challenge this assumption by developing a quantitative approach for the analysis of the pro- and antioxidant ability of human embryonic stem cells in comparison with their differentiated descendants, as well as adult stem and non-stem cells. Our measurements showed that embryonic stem cells are characterized by low ROS level, low rate of extracellular hydrogen peroxide removal and low threshold for peroxide-induced cytotoxicity. However, biochemical normalization of these parameters to cell volume/protein leads to matching of normalized values in stem and differentiated cells and shows that tested in the present study cells (human embryonic stem cells and their fibroblast-like progenies, adult mesenchymal stem cells, lymphocytes, HeLa) maintain similar intracellular redox status. Based on these observations, we propose to use ROS concentration averaged over the cell volume instead of ROS level as a measure of intracellular redox balance. We show that attempts to use ROS level for comparative analysis of redox status of morphologically different cells could lead to false conclusions. Methods for the assessment of ROS concentration based on flow cytometry analysis with the use of H 2 DCFDA dye and HyPer, genetically encoded probe for hydrogen peroxide, are discussed. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Stem cells in retinal regeneration: past, present and future.

PubMed

Ramsden, Conor M; Powner, Michael B; Carr, Amanda-Jayne F; Smart, Matthew J K; da Cruz, Lyndon; Coffey, Peter J

2013-06-01

Stem cell therapy for retinal disease is under way, and several clinical trials are currently recruiting. These trials use human embryonic, foetal and umbilical cord tissue-derived stem cells and bone marrow-derived stem cells to treat visual disorders such as age-related macular degeneration, Stargardt's disease and retinitis pigmentosa. Over a decade of analysing the developmental cues involved in retinal generation and stem cell biology, coupled with extensive surgical research, have yielded differing cellular approaches to tackle these retinopathies. Here, we review these various stem cell-based approaches for treating retinal diseases and discuss future directions and challenges for the field.

The potential of nanofibers in tissue engineering and stem cell therapy.

PubMed

Gholizadeh-Ghaleh Aziz, Shiva; Gholizadeh-Ghaleh Aziz, Sara; Akbarzadeh, Abolfazl

2016-08-01

Electrospinning is a technique in which materials in solution are shaped into continuous nano- and micro-sized fibers. Combining stem cells with biomaterial scaffolds and nanofibers affords a favorable approach for bone tissue engineering, stem cell growth and transfer, ocular surface reconstruction, and treatment of congenital corneal diseases. This review seeks to describe the current examples of the use of scaffolds in stem cell therapy. Stem cells are classified as adult or embryonic stem (ES) cells, and the advantages and drawbacks of each group are detailed. The nanofibers and scaffolds are further classified in Tables I and II , which describe specific examples from the literature. Finally, the current applications of biomaterial scaffolds containing stem cells for tissue engineering applications are presented. Overall, this review seeks to give an overview of the biomaterials available for use in combination with stem cells, and the application of nanofibers in stem cell therapy.

Engineering Stem Cells for Biomedical Applications

PubMed Central

Yin, Perry T.; Han, Edward

2018-01-01

Stem cells are characterized by a number of useful properties, including their ability to migrate, differentiate, and secrete a variety of therapeutic molecules such as immunomodulatory factors. As such, numerous pre-clinical and clinical studies have utilized stem cell-based therapies and demonstrated their tremendous potential for the treatment of various human diseases and disorders. Recently, efforts have focused on engineering stem cells in order to further enhance their innate abilities as well as to confer them with new functionalities, which can then be used in various biomedical applications. These engineered stem cells can take on a number of forms. For instance, engineered stem cells encompass the genetic modification of stem cells as well as the use of stem cells for gene delivery, nanoparticle loading and delivery, and even small molecule drug delivery. The present Review gives an in-depth account of the current status of engineered stem cells, including potential cell sources, the most common methods used to engineer stem cells, and the utilization of engineered stem cells in various biomedical applications, with a particular focus on tissue regeneration, the treatment of immunodeficiency diseases, and cancer. PMID:25772134

Materials as stem cell regulators

PubMed Central

Murphy, William L.; McDevitt, Todd C.; Engler, Adam J.

2014-01-01

The stem cell/material interface is a complex, dynamic microenvironment in which the cell and the material cooperatively dictate one another's fate: the cell by remodelling its surroundings, and the material through its inherent properties (such as adhesivity, stiffness, nanostructure or degradability). Stem cells in contact with materials are able to sense their properties, integrate cues via signal propagation and ultimately translate parallel signalling information into cell fate decisions. However, discovering the mechanisms by which stem cells respond to inherent material characteristics is challenging because of the highly complex, multicomponent signalling milieu present in the stem cell environment. In this Review, we discuss recent evidence that shows that inherent material properties may be engineered to dictate stem cell fate decisions, and overview a subset of the operative signal transduction mechanisms that have begun to emerge. Further developments in stem cell engineering and mechanotransduction are poised to have substantial implications for stem cell biology and regenerative medicine. PMID:24845994

Stem Cell Therapy for Treatment of Ocular Disorders

PubMed Central

Sivan, Padma Priya; Syed, Sakinah; Mok, Pooi-Ling; Higuchi, Akon; Murugan, Kadarkarai; Alarfaj, Abdullah A.; Munusamy, Murugan A.; Awang Hamat, Rukman; Umezawa, Akihiro; Kumar, Suresh

2016-01-01

Sustenance of visual function is the ultimate focus of ophthalmologists. Failure of complete recovery of visual function and complications that follow conventional treatments have shifted search to a new form of therapy using stem cells. Stem cell progenitors play a major role in replenishing degenerated cells despite being present in low quantity and quiescence in our body. Unlike other tissues and cells, regeneration of new optic cells responsible for visual function is rarely observed. Understanding the transcription factors and genes responsible for optic cells development will assist scientists in formulating a strategy to activate and direct stem cells renewal and differentiation. We review the processes of human eye development and address the strategies that have been exploited in an effort to regain visual function in the preclinical and clinical state. The update of clinical findings of patients receiving stem cell treatment is also presented. PMID:27293447

Concise review: Patient-derived olfactory stem cells: new models for brain diseases.

PubMed

Mackay-Sim, Alan

2012-11-01

Traditional models of brain diseases have had limited success in driving candidate drugs into successful clinical translation. This has resulted in large international pharmaceutical companies moving out of neuroscience research. Cells are not brains, obviously, but new patient-derived stem models have the potential to elucidate cell biological aspects of brain diseases that are not present in worm, fly, or rodent models, the work horses of disease investigations and drug discovery. Neural stem cells are present in the olfactory mucosa, the organ of smell in the nose. Patient-derived olfactory mucosa has demonstrated disease-associated differences in a variety of brain diseases and recently olfactory mucosa stem cells have been generated from patients with schizophrenia, Parkinson's disease, and familial dysautonomia. By comparison with cells from healthy controls, patient-derived olfactory mucosa stem cells show disease-specific alterations in gene expression and cell functions including: a shorter cell cycle and faster proliferation in schizophrenia, oxidative stress in Parkinson's disease, and altered cell migration in familial dysautonomia. Olfactory stem cell cultures thus reveal patient-control differences, even in complex genetic diseases such as schizophrenia and Parkinson's disease, indicating that multiple genes of small effect can converge on shared cell signaling pathways to present as a disease-specific cellular phenotype. Olfactory mucosa stem cells can be maintained in homogeneous cultures that allow robust and repeatable multiwell assays suitable for screening libraries of drug candidate molecules. Copyright © 2012 AlphaMed Press.

The clinical use of regenerative therapy in COPD

PubMed Central

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

2014-01-01

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

Anti-Cancer Phytometabolites Targeting Cancer Stem Cells

PubMed Central

Torquato, Heron F.V.; Goettert, Márcia I.; Justo, Giselle Z.; Paredes-Gamero, Edgar J.

2017-01-01

Medicinal plants are a plentiful source of bioactive molecules with much structural diversity. In cancer treatment, molecules obtained from plants represent an attractive alternative to other treatments because several plant-derived compounds have exhibited lower toxicity and higher selectivity against cancer cells. In this review, we focus on the possible application of bioactive molecules obtained from plants against more primitive cell populations in cancers, cancer stem cells. Cancer stem cells are present in several kinds of tumors and are responsible for recurrences and metastases. Common anti-cancer drugs exhibit lower effectiveness against cancer stem cells because of their biological features. However, recently discovered natural phytometabolites exert cytotoxic effects on this rare population of cells in cancers. Therefore, this review presents the latest research on promising compounds from plants that can act as antitumor drugs and that mainly affect stem cell populations in cancers. PMID:28367074

mTOR plays critical roles in pancreatic cancer stem cells through specific and stemness-related functions

NASA Astrophysics Data System (ADS)

Matsubara, Shyuichiro; Ding, Qiang; Miyazaki, Yumi; Kuwahata, Taisaku; Tsukasa, Koichiro; Takao, Sonshin

2013-11-01

Pancreatic cancer is characterized by near-universal mutations in KRAS. The mammalian target of rapamycin (mTOR), which functions downstream of RAS, has divergent effects on stem cells. In the present study, we investigated the significance of the mTOR pathway in maintaining the properties of pancreatic cancer stem cells. The mTOR inhibitor, rapamycin, reduced the viability of CD133+ pancreatic cancer cells and sphere formation which is an index of self-renewal of stem-like cells, indicating that the mTOR pathway functions to maintain cancer stem-like cells. Further, rapamycin had different effects on CD133+ cells compared to cyclopamine which is an inhibitor of the Hedgehog pathway. Thus, the mTOR pathway has a distinct role although both pathways maintain pancreatic cancer stem cells. Therefore, mTOR might be a promising target to eliminate pancreatic cancer stem cells.

Stem cells in nephrology: present status and future.

PubMed

Watorek, Ewa; Klinger, Marian

2006-01-01

Stem cell biology is currently developing rapidly because of the potential therapeutic utility of stem cells. The ability to acquire any desired phenotype raises hope for regenerative therapies. Manipulation of these cells is a potentially valuable tool; however, the mechanisms of stem cell differentiation and plasticity are currently beyond our control. In the field of nephrology, the presence of adult kidney stem cells has been debated. Renal adult stem cells may be descendants of some early kidney progenitors, or may be derived from bone marrow. Evidence of a hematopoietic stem-cell contribution to renal repair encourages the possibility of bone marrow or stem cell transplantation as a means of treating autoimmune glomerulopathies. The transplantation of fetal kidney tissue containing renal progenitors, which then develop into functional nephrons, is a step towards renal regeneration. According to recent reports, the development of functional nephrons from human mesenchymal stem cells in rodent whole-embryo culture is possible. Establishing in vitro self organs from autologous stem cells would be a promising therapeutic solution in light of the shortage of allogenic organs and the unresolved problem of chronic allograft rejection.

[The emerging technology of tissue engineering : Focus on stem cell niche].

PubMed

Schlötzer-Schrehardt, U; Freudenberg, U; Kruse, F E

2017-04-01

Limbal stem cells reside in a highly specialized complex microenvironment that is known as the stem cell niche, an anatomically protected region at the bottom of the Palisades of Vogt, where the stem cells are located and where their quiescence, proliferation and differentiation are maintained in balance. Besides the epithelial stem and progenitor cell clusters, the limbal niche comprises several types of supporting niche cells and a specific extracellular matrix mediating biochemical and biophysical signals. Stem cell-based tissue engineering aims to mimic the native stem cell niche and to present appropriate microenvironmental cues in a controlled and reproducible fashion in order to maintain stem cell function within the graft. Current therapeutic approaches for ex vivo expansion of limbal stem cells only take advantage of surrogate niches. However, new insights into the molecular composition of the limbal niche and innovative biosynthetic scaffolds have stimulated novel strategies for niche-driven stem cell cultivation. Promising experimental approaches include collagen-based organotypic coculture systems of limbal epithelial stem cells with their niche cells and biomimetic hydrogel platforms prefunctionalized with appropriate biomolecular and biophysical signals. Future translation of these novel regenerative strategies into clinical application is expected to improve long-term outcomes of limbal stem cell transplantation for ocular surface reconstruction.

Laser biomodulation on stem cells

NASA Astrophysics Data System (ADS)

Liu, Timon C.; Duan, Rui; Li, Yan; Li, Xue-Feng; Tan, Li-Ling; Liu, Songhao

2001-08-01

Stem cells are views from the perspectives of their function, evolution, development, and cause. Counterintuitively, most stem cells may arise late in development, to act principally in tissue renewal, thus ensuring an organisms long-term survival. Surprisingly, recent reports suggest that tissue-specific adult stem cells have the potential to contribute to replenishment of multiple adult tissues. Stem cells are currently in the news for two reasons: the successful cultivation of human embryonic stem cell lines and reports that adult stem cells can differentiate into developmentally unrelated cell types, such as nerve cells into blood cells. The spotlight on stem cells has revealed gaps in our knowledge that must be filled if we are to take advantage of their full potential for treating devastating degenerative diseases such as Parkinsons's disease and muscular dystrophy. We need to know more about the intrinsic controls that keep stem cells as stem cells or direct them along particular differentiation pathways. Such intrinsic regulators are, in turn, sensitive to the influences of the microenvironment, or niche, where stem cells normally reside. Both intrinsic and extrinsic signals regular stem cell fate and some of these signals have now been identified. Vacek et al and Wang et al have studied the effect of low intensity laser on the haemopoietic stem cells in vitro. There experiments show there is indeed the effect of low intensity laser on the haemopoietic stem cells in vitro, and the present effect is the promotion of haemopoietic stem cells proliferation. In other words, low intensity laser irradiation can act as an extrinsic signal regulating stem cell fate. In this paper, we study how low intensity laser can be used to regulate stem cell fate from the viewpoint of collective phototransduction.

Diabetes and Stem Cell Function

PubMed Central

Fujimaki, Shin; Wakabayashi, Tamami; Takemasa, Tohru; Asashima, Makoto; Kuwabara, Tomoko

2015-01-01

Diabetes mellitus is one of the most common serious metabolic diseases that results in hyperglycemia due to defects of insulin secretion or insulin action or both. The present review focuses on the alterations to the diabetic neuronal tissues and skeletal muscle, including stem cells in both tissues, and the preventive effects of physical activity on diabetes. Diabetes is associated with various nervous disorders, such as cognitive deficits, depression, and Alzheimer's disease, and that may be caused by neural stem cell dysfunction. Additionally, diabetes induces skeletal muscle atrophy, the impairment of energy metabolism, and muscle weakness. Similar to neural stem cells, the proliferation and differentiation are attenuated in skeletal muscle stem cells, termed satellite cells. However, physical activity is very useful for preventing the diabetic alteration to the neuronal tissues and skeletal muscle. Physical activity improves neurogenic capacity of neural stem cells and the proliferative and differentiative abilities of satellite cells. The present review proposes physical activity as a useful measure for the patients in diabetes to improve the physiological functions and to maintain their quality of life. It further discusses the use of stem cell-based approaches in the context of diabetes treatment. PMID:26075247

Engineering Stem Cells for Biomedical Applications.

PubMed

Yin, Perry T; Han, Edward; Lee, Ki-Bum

2016-01-07

Stem cells are characterized by a number of useful properties, including their ability to migrate, differentiate, and secrete a variety of therapeutic molecules such as immunomodulatory factors. As such, numerous pre-clinical and clinical studies have utilized stem cell-based therapies and demonstrated their tremendous potential for the treatment of various human diseases and disorders. Recently, efforts have focused on engineering stem cells in order to further enhance their innate abilities as well as to confer them with new functionalities, which can then be used in various biomedical applications. These engineered stem cells can take on a number of forms. For instance, engineered stem cells encompass the genetic modification of stem cells as well as the use of stem cells for gene delivery, nanoparticle loading and delivery, and even small molecule drug delivery. The present Review gives an in-depth account of the current status of engineered stem cells, including potential cell sources, the most common methods used to engineer stem cells, and the utilization of engineered stem cells in various biomedical applications, with a particular focus on tissue regeneration, the treatment of immunodeficiency diseases, and cancer. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Analysis of the Contribution of Stem Cells to Breast Cancer Using Microchimerism-Based Y-Chromosome Stains and Histopathology

DTIC Science & Technology

2005-07-01

stroma), if any, have originated from the body’s circulating stem cell pool, using the Y- chromosome in micro-chimeric mothers . Such a cell may present... Transplanted or chimeric Y chromosome-bearing stem cells behave as do the mothers own: proliferating, differentiating and incorporating into... Transplanted or chimeric Y chromosome-bearing stem cells behave as do the mothers own: aggregating, proliferating, and differentiating(Petersen

Selection of Phage Display Peptides Targeting Human Pluripotent Stem Cell-Derived Progenitor Cell Lines.

PubMed

Bignone, Paola A; Krupa, Rachel A; West, Michael D; Larocca, David

2016-01-01

The ability of human pluripotent stem cells (hPS) to both self-renew and differentiate into virtually any cell type makes them a promising source of cells for cell-based regenerative therapies. However, stem cell identity, purity, and scalability remain formidable challenges that need to be overcome for translation of pluripotent stem cell research into clinical applications. Directed differentiation from hPS cells is inefficient and residual contamination with pluripotent cells that have the potential to form tumors remains problematic. The derivation of scalable (self-renewing) embryonic progenitor stem cell lines offers a solution because they are well defined and clonally pure. Clonally pure progenitor stem cell lines also provide a means for identifying cell surface targeting reagents that are useful for identification, tracking, and repeated derivation of the corresponding progenitor stem cell types from additional hPS cell sources. Such stem cell targeting reagents can then be applied to the manufacture of genetically diverse banks of human embryonic progenitor cell lines for drug screening, disease modeling, and cell therapy. Here we present methods to identify human embryonic progenitor stem cell targeting peptides by selection of phage display libraries on clonal embryonic progenitor cell lines and demonstrate their use for targeting quantum dots (Qdots) for stem cell labeling.

Advances and Prospects in Stem Cells for Cartilage Regeneration

PubMed Central

Wang, Mingjie; Yuan, Zhiguo; Ma, Ning; Hao, Chunxiang; Guo, Weimin; Zou, Gengyi; Zhang, Yu; Chen, Mingxue; Gao, Shuang; Wang, Aiyuan; Wang, Yu; Sui, Xiang; Xu, Wenjing; Lu, Shibi

2017-01-01

The histological features of cartilage call attention to the fact that cartilage has a little capacity to repair itself owing to the lack of a blood supply, nerves, or lymphangion. Stem cells have emerged as a promising option in the field of cartilage tissue engineering and regenerative medicine and could lead to cartilage repair. Much research has examined cartilage regeneration utilizing stem cells. However, both the potential and the limitations of this procedure remain controversial. This review presents a summary of emerging trends with regard to using stem cells in cartilage tissue engineering and regenerative medicine. In particular, it focuses on the characterization of cartilage stem cells, the chondrogenic differentiation of stem cells, and the various strategies and approaches involving stem cells that have been used in cartilage repair and clinical studies. Based on the research into chondrocyte and stem cell technologies, this review discusses the damage and repair of cartilage and the clinical application of stem cells, with a view to increasing our systematic understanding of the application of stem cells in cartilage regeneration; additionally, several advanced strategies for cartilage repair are discussed. PMID:28246531

Pluripotent stem cells and reprogrammed cells in farm animals.

PubMed

Nowak-Imialek, Monika; Kues, Wilfried; Carnwath, Joseph W; Niemann, Heiner

2011-08-01

Pluripotent cells are unique because of their ability to differentiate into the cell lineages forming the entire organism. True pluripotent stem cells with germ line contribution have been reported for mice and rats. Human pluripotent cells share numerous features of pluripotentiality, but confirmation of their in vivo capacity for germ line contribution is impossible due to ethical and legal restrictions. Progress toward derivation of embryonic stem cells from domestic species has been made, but the derived cells were not able to produce germ line chimeras and thus are termed embryonic stem-like cells. However, domestic animals, in particular the domestic pig (Sus scrofa), are excellent large animals models, in which the clinical potential of stem cell therapies can be studied. Reprogramming technologies for somatic cells, including somatic cell nuclear transfer, cell fusion, in vitro culture in the presence of cell extracts, in vitro conversion of adult unipotent spermatogonial stem cells into germ line derived pluripotent stem cells, and transduction with reprogramming factors have been developed with the goal of obtaining pluripotent, germ line competent stem cells from domestic animals. This review summarizes the present state of the art in the derivation and maintenance of pluripotent stem cells in domestic animals.

[Using cell technologies to treat urologic diseases].

PubMed

Glybochko, P V; Olefir, Yu V; Alyaev, Yu G; Butnaru, D V; Bezrukov, E A; Chaplenko, A A; Zharikova, T M

2016-08-01

Stem and progenitor cells being introduced into the body have the ability to stimulate regeneration of tissues and organs by differentiating into specialized cells. Stem cell therapy is used in urology to treat various disorders, including erectile dysfunction, urinary incontinence, Peyronies disease, and male infertility. This review presents the results of international preclinical and clinical research on stem cell based medications for treating the above diseases. The most promising appears to be the use of adipose tissue-derived mesenchymal stem cells.

Intestinal stem cells and their defining niche.

PubMed

Tan, David Wei-Min; Barker, Nick

2014-01-01

The intestinal epithelium is a classic example of a rapidly self-renewing tissue fueled by dedicated resident stem cells. These stem cells reside at the crypt base, generating committed progeny that mature into the various functional epithelial lineages while following a rapid migratory path toward the villi. Two models of intestinal stem cell location were proposed half a century ago and data have been presented in support of both models, dividing the scientific community. Molecular markers have been identified and validated using new techniques such as in vivo lineage tracing and ex vivo organoid culture. The intestinal stem cell niche comprises both epithelial cells, in particular the Paneth cell, and the stromal compartment, where cell-associated ligands and soluble factors regulate stem cell behavior. This review highlights the recent advances in identifying and characterizing the intestinal stem cells and their defining niche. © 2014 Elsevier Inc. All rights reserved.

Nanomaterials modulate stem cell differentiation: biological interaction and underlying mechanisms.

PubMed

Wei, Min; Li, Song; Le, Weidong

2017-10-25

Stem cells are unspecialized cells that have the potential for self-renewal and differentiation into more specialized cell types. The chemical and physical properties of surrounding microenvironment contribute to the growth and differentiation of stem cells and consequently play crucial roles in the regulation of stem cells' fate. Nanomaterials hold great promise in biological and biomedical fields owing to their unique properties, such as controllable particle size, facile synthesis, large surface-to-volume ratio, tunable surface chemistry, and biocompatibility. Over the recent years, accumulating evidence has shown that nanomaterials can facilitate stem cell proliferation and differentiation, and great effort is undertaken to explore their possible modulating manners and mechanisms on stem cell differentiation. In present review, we summarize recent progress in the regulating potential of various nanomaterials on stem cell differentiation and discuss the possible cell uptake, biological interaction and underlying mechanisms.

Role of bioinspired polymers in determination of pluripotent stem cell fate

PubMed Central

Abraham, Sheena; Eroshenko, Nikolai; Rao, Raj R

2009-01-01

Human pluripotent stem cells, including embryonic and induced pluripotent stem cells, hold enormous potential for the treatment of many diseases, owing to their ability to generate cell types useful for therapeutic applications. Currently, many stem cell culture propagation and differentiation systems incorporate animal-derived components for promoting self-renewal and differentiation. However, use of these components is labor intensive, carries the risk of xenogeneic contamination and yields compromised experimental results that are difficult to duplicate. From a biomaterials perspective, the generation of an animal- and cell-free biomimetic microenvironment that provides the appropriate physical and chemical cues for stem cell self-renewal or differentiation into specialized cell types would be ideal. This review presents the use of natural and synthetic polymers that support propagation and differentiation of stem cells, in an attempt to obtain a clear understanding of the factors responsible for the determination of stem cell fate. PMID:19580405

Clinical observation of the application of autologous peripheral blood stem cell transplantation for the treatment of diabetic foot gangrene

PubMed Central

XU, SHI-MIN; LIANG, TING

2016-01-01

The aim of the present study was to investigate the optimal mobilization plan in autologous peripheral blood stem cell transplantation for the treatment of diabetic foot and to observe its clinical curative effect. A total of 127 patients with diabetic foot were treated with different doses of granulocyte colony stimulating factor (G-CSF) to mobilize their hematopoietic stem cells. Subsequently, the extracted stem cell suspension was injected into the ischemic lower extremities along the blood vessels in the areas presenting with pathological changes. Following the treatment, the intermittent claudication distance, skin temperature, ankle brachial index and pain scores of the patients were evaluated. In addition, the associations among the mobilization time, doses and peripheral blood CD34+ level were analyzed. The collection efficiency of the stem cells was associated with the dose of G-CSF and the mobilization time. Following the injection of the autologous peripheral blood stem cell suspension, the ischemic area of the patients was improved significantly. In conclusion, autologous peripheral blood stem cell transplantation can promote the establishment of collateral circulation in patients with diabetic foot, and the optimal time for gathering stem cells is closely correlated with the peripheral blood CD34+ level. PMID:26889255

Stem Cells in Skeletal Tissue Engineering: Technologies and Models

PubMed Central

Langhans, Mark T.; Yu, Shuting; Tuan, Rocky S.

2017-01-01

This review surveys the use of pluripotent and multipotent stem cells in skeletal tissue engineering. Specific emphasis is focused on evaluating the function and activities of these cells in the context of development in vivo, and how technologies and methods of stem cell-based tissue engineering for stem cells must draw inspiration from developmental biology. Information on the embryonic origin and in vivo differentiation of skeletal tissues is first reviewed, to shed light on the persistence and activities of adult stem cells that remain in skeletal tissues after embryogenesis. Next, the development and differentiation of pluripotent stem cells is discussed, and some of their advantages and disadvantages in the context of tissue engineering is presented. The final section highlights current use of multipotent adult mesenchymal stem cells, reviewing their origin, differentiation capacity, and potential applications to tissue engineering. PMID:26423296

Human embryonic stem cells and good manufacturing practice: Report of a 1- day workshop held at Stem Cell Biology Research Center, Yazd, 27th April 2017.

PubMed

Akyash, Fatemeh; Sadeghian-Nodoushan, Fatemeh; Tahajjodi, Somayyeh Sadat; Nikukar, Habib; Farashahi Yazd, Ehsan; Azimzadeh, Mostafa; D Moore, Harry; Aflatoonian, Behrouz

2017-05-01

This report explains briefly the minutes of a 1-day workshop entitled; "human embryonic stem cells (hESCs) and good manufacturing practice (GMP)" held by Stem Cell Biology Research Center based in Yazd Reproductive Sciences Institute at Shahid Sadoughi University of Medical Sciences, Yazd, Iran on 27 th April 2017. In this workshop, in addition to the practical sessions, Prof. Harry D. Moore from Centre for Stem Cell Biology, University of Sheffield, UK presented the challenges and the importance of the biotechnology of clinical-grade human embryonic stem cells from first derivation to robust defined culture for therapeutic applications.

Epithelial-mesenchymal transition transcription factors control pluripotent adult stem cell migration in vivo in planarians

PubMed Central

Abnave, Prasad; Aboukhatwa, Ellen; Kosaka, Nobuyoshi; Thompson, James; Hill, Mark A.

2017-01-01

Migration of stem cells underpins the physiology of metazoan animals. For tissues to be maintained, stem cells and their progeny must migrate and differentiate in the correct positions. This need is even more acute after tissue damage by wounding or pathogenic infection. Inappropriate migration also underpins metastasis. Despite this, few mechanistic studies address stem cell migration during repair or homeostasis in adult tissues. Here, we present a shielded X-ray irradiation assay that allows us to follow stem cell migration in planarians. We demonstrate the use of this system to study the molecular control of stem cell migration and show that snail-1, snail-2 and zeb-1 EMT transcription factor homologs are necessary for cell migration to wound sites and for the establishment of migratory cell morphology. We also observed that stem cells undergo homeostatic migration to anterior regions that lack local stem cells, in the absence of injury, maintaining tissue homeostasis. This requires the polarity determinant notum. Our work establishes planarians as a suitable model for further in-depth study of the processes controlling stem cell migration in vivo. PMID:28893948

Biliary tract cancer stem cells - translational options and challenges

PubMed Central

Mayr, Christian; Ocker, Matthias; Ritter, Markus; Pichler, Martin; Neureiter, Daniel; Kiesslich, Tobias

2017-01-01

Management of biliary tract cancer remains challenging. Tumors show high recurrence rates and therapeutic resistance, leading to dismal prognosis and short survival. The cancer stem cell model states that a tumor is a heterogeneous conglomerate of cells, in which a certain subpopulation of cells - the cancer stem cells - possesses stem cell properties. Cancer stem cells have high clinical relevance due to their potential contributions to development, progression and aggressiveness as well as recurrence and metastasis of malignant tumors. Consequently, reliable identification of as well as pharmacological intervention with cancer stem cells is an intensively investigated and promising research field. The involvement of cancer stem cells in biliary tract cancer is likely as a number of studies demonstrated their existence and the obvious clinical relevance of several established cancer stem cell markers in biliary tract cancer models and tissues. In the present article, we review and discuss the currently available literature addressing the role of putative cancer stem cells in biliary tract cancer as well as the connection between known contributors of biliary tract tumorigenesis such as oncogenic signaling pathways, micro-RNAs and the tumor microenvironment with cancer stem cells. PMID:28465631

Immobilization of Heparan Sulfate on Electrospun Meshes to Support Embryonic Stem Cell Culture and Differentiation*

PubMed Central

Meade, Kate A.; White, Kathryn J.; Pickford, Claire E.; Holley, Rebecca J.; Marson, Andrew; Tillotson, Donna; van Kuppevelt, Toin H.; Whittle, Jason D.; Day, Anthony J.; Merry, Catherine L. R.

2013-01-01

As our understanding of what guides the behavior of multi- and pluripotent stem cells deepens, so too does our ability to utilize certain cues to manipulate their behavior and maximize their therapeutic potential. Engineered, biologically functionalized materials have the capacity to influence stem cell behavior through a powerful combination of biological, mechanical, and topographical cues. Here, we present the development of a novel electrospun scaffold, functionalized with glycosaminoglycans (GAGs) ionically immobilized onto the fiber surface. Bound GAGs retained the ability to interact with GAG-binding molecules and, crucially, presented GAG sulfation motifs fundamental to mediating stem cell behavior. Bound GAG proved to be biologically active, rescuing the neural differentiation capacity of heparan sulfate-deficient mouse embryonic stem cells and functioning in concert with FGF4 to facilitate the formation of extensive neural processes across the scaffold surface. The combination of GAGs with electrospun scaffolds creates a biomaterial with potent applicability for the propagation and effective differentiation of pluripotent stem cells. PMID:23235146

Immobilization of heparan sulfate on electrospun meshes to support embryonic stem cell culture and differentiation.

PubMed

Meade, Kate A; White, Kathryn J; Pickford, Claire E; Holley, Rebecca J; Marson, Andrew; Tillotson, Donna; van Kuppevelt, Toin H; Whittle, Jason D; Day, Anthony J; Merry, Catherine L R

2013-02-22

As our understanding of what guides the behavior of multi- and pluripotent stem cells deepens, so too does our ability to utilize certain cues to manipulate their behavior and maximize their therapeutic potential. Engineered, biologically functionalized materials have the capacity to influence stem cell behavior through a powerful combination of biological, mechanical, and topographical cues. Here, we present the development of a novel electrospun scaffold, functionalized with glycosaminoglycans (GAGs) ionically immobilized onto the fiber surface. Bound GAGs retained the ability to interact with GAG-binding molecules and, crucially, presented GAG sulfation motifs fundamental to mediating stem cell behavior. Bound GAG proved to be biologically active, rescuing the neural differentiation capacity of heparan sulfate-deficient mouse embryonic stem cells and functioning in concert with FGF4 to facilitate the formation of extensive neural processes across the scaffold surface. The combination of GAGs with electrospun scaffolds creates a biomaterial with potent applicability for the propagation and effective differentiation of pluripotent stem cells.

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.

Placental-derived stem cells: Culture, differentiation and challenges

PubMed Central

Oliveira, Maira S; Barreto-Filho, João B

2015-01-01

Stem cell therapy is a promising approach to clinical healing in several diseases. A great variety of tissues (bone marrow, adipose tissue, and placenta) are potentially sources of stem cells. Placenta-derived stem cells (p-SCs) are in between embryonic and mesenchymal stem cells, sharing characteristics with both, such as non-carcinogenic status and property to differentiate in all embryonic germ layers. Moreover, their use is not ethically restricted as fetal membranes are considered medical waste after birth. In this context, the present review will be focused on the biological properties, culture and potential cell therapy uses of placental-derived stem cells. Immunophenotype characterization, mainly for surface marker expression, and basic principles of p-SC isolation and culture (mechanical separation or enzymatic digestion of the tissues, the most used culture media, cell plating conditions) will be presented. In addition, some preclinical studies that were performed in different medical areas will be cited, focusing on neurological, liver, pancreatic, heart, muscle, pulmonary, and bone diseases and also in tissue engineering field. Finally, some challenges for stem cell therapy applications will be highlighted. The understanding of the mechanisms involved in the p-SCs differentiation and the achievement of pure cell populations (after differentiation) are key points that must be clarified before bringing the preclinical studies, performed at the bench, to the medical practice. PMID:26029347

Large Scale Production of Stem Cells and Their Derivatives

NASA Astrophysics Data System (ADS)

Zweigerdt, Robert

Stem cells have been envisioned to become an unlimited cell source for regenerative medicine. Notably, the interest in stem cells lies beyond direct therapeutic applications. They might also provide a previously unavailable source of valuable human cell types for screening platforms, which might facilitate the development of more efficient and safer drugs. The heterogeneity of stem cell types as well as the numerous areas of application suggests that differential processes are mandatory for their in vitro culture. Many of the envisioned applications would require the production of a high number of stem cells and their derivatives in scalable, well-defined and potentially clinical compliant manner under current good manufacturing practice (cGMP). In this review we provide an overview on recent strategies to develop bioprocesses for the expansion, differentiation and enrichment of stem cells and their progenies, presenting examples for adult and embryonic stem cells alike.

Genetic modification of hematopoietic stem cells: recent advances in the gene therapy of inherited diseases.

PubMed

Bueren, Juan A; Guenechea, Guillermo; Casado, José A; Lamana, María Luisa; Segovia, José C

2003-01-01

Hematopoietic stem cells constitute a rare population of precursor cells with remarkable properties for being used as targets in gene therapy protocols. The last years have been particularly productive both in the fields of gene therapy and stem cell biology. Results from ongoing clinical trials have shown the first unquestionable clinical benefits of immunodeficient patients transplanted with genetically modified autologous stem cells. On the other hand, severe side effects in a few patients treated with gene therapy have also been reported, indicating the usefulness of further improving the vectors currently used in gene therapy clinical trials. In the field of stem cell biology, evidence showing the plastic potential of adult hematopoietic stem cells and data indicating the multipotency of adult mesenchymal precursor cells have been presented. Also, the generation of embryonic stem cells by means of nuclear transfer techniques has appeared as a new methodology with direct implications in gene therapy.

Incorporation of Biomaterials in Multicellular Aggregates Modulates Pluripotent Stem Cell Differentiation

PubMed Central

Bratt-Leal, Andrés M.; Carpenedo, Richard L.; Ungrin, Mark; Zandstra, Peter W.; McDevitt, Todd C.

2010-01-01

Biomaterials are increasingly being used to engineer the biochemical and biophysical properties of the extracellular stem cell microenvironment in order to tailor niche characteristics and direct cell phenotype. To date, stem cell-biomaterial interactions have largely been studied by introducing stem cells into artificial environments, such as 2D cell culture on biomaterial surfaces, encapsulation of cell suspensions within hydrogel materials, or cell seeding on 3D polymeric scaffolds. In this study, microparticles fabricated from different materials, such as agarose, PLGA and gelatin, were stably integrated, in a dose-dependent manner, within aggregates of pluripotent stem cells (PSCs) prior to differentiation as a means to directly examine stem cell-biomaterial interactions in 3D. Interestingly, the presence of the materials within the stem cell aggregates differentially modulated the gene and protein expression patterns of several differentiation markers without adversely affecting cell viability. Microparticle incorporation within 3D stem cell aggregates can control the spatial presentation of extracellular environmental cues (i.e. soluble factors, extracellular matrix and intercellular adhesion molecules) as a means to direct the differentiation of stem cells for tissue engineering and regenerative medicine applications. In addition, these results suggest that the physical presence of microparticles within stem cell aggregates does not compromise PSC differentiation, but in fact the choice of biomaterials can impact the propensity of stem cells to adopt particular differentiated cell phenotypes. PMID:20864164

Metabolic rate determines haematopoietic stem cell self-renewal.

PubMed

Sastry, P S R K

2004-01-01

The number of haematopoietic stem cells (HSCs) per animal is conserved across species. This means the HSCs need to maintain hematopoiesis over a longer period in larger animals. This would result in the requirement of stem cell self-renewal. At present the three existing models are the stochastic model, instructive model and the third more recently proposed is the chiaro-scuro model. It is a well known allometric law that metabolic rate scales to the three quarter power. Larger animals have a lower metabolic rate, compared to smaller animals. Here it is being hypothesized that metabolic rate determines haematopoietic stem cell self-renewal. At lower metabolic rate the stem cells commit for self-renewal, where as at higher metabolic rate they become committed to different lineages. The present hypothesis can explain the salient features of the different models. Recent findings regarding stem cell self-renewal suggest an important role for Wnt proteins and their receptors known as frizzleds, which are an important component of cell signaling pathway. The role of cGMP in the Wnts action provides further justification for the present hypothesis as cGMP is intricately linked to metabolic rate. One can also explain the telomere homeostasis by the present hypothesis. One prediction of the present hypothesis is with reference to the limit of cell divisions known as Hayflick limit, here it is being suggested that this is the result of metabolic rate in laboratory conditions and there can be higher number of cell divisions in vivo if the metabolic rate is lower. Copyright 2004 Elsevier Ltd.

Multipotent adult germ-line stem cells, like other pluripotent stem cells, can be killed by cytotoxic T lymphocytes despite low expression of major histocompatibility complex class I molecules

PubMed Central

Dressel, Ralf; Guan, Kaomei; Nolte, Jessica; Elsner, Leslie; Monecke, Sebastian; Nayernia, Karim; Hasenfuss, Gerd; Engel, Wolfgang

2009-01-01

Background Multipotent adult germ-line stem cells (maGSCs) represent a new pluripotent cell type that can be derived without genetic manipulation from spermatogonial stem cells (SSCs) present in adult testis. Similarly to induced pluripotent stem cells (iPSCs), they could provide a source of cellular grafts for new transplantation therapies of a broad variety of diseases. To test whether these stem cells can be rejected by the recipients, we have analyzed whether maGSCs and iPSCs can become targets for cytotoxic T lymphocytes (CTL) or whether they are protected, as previously proposed for embryonic stem cells (ESCs). Results We have observed that maGSCs can be maintained in prolonged culture with or without leukemia inhibitory factor and/or feeder cells and still retain the capacity to form teratomas in immunodeficient recipients. They were, however, rejected in immunocompetent allogeneic recipients, and the immune response controlled teratoma growth. We analyzed the susceptibility of three maGSC lines to CTL in comparison to ESCs, iPSCs, and F9 teratocarcinoma cells. Major histocompatibility complex (MHC) class I molecules were not detectable by flow cytometry on these stem cell lines, apart from low levels on one maGSC line (maGSC Stra8 SSC5). However, using a quantitative real time PCR analysis H2K and B2m transcripts were detected in all pluripotent stem cell lines. All pluripotent stem cell lines were killed in a peptide-dependent manner by activated CTLs derived from T cell receptor transgenic OT-I mice after pulsing of the targets with the SIINFEKL peptide. Conclusion Pluripotent stem cells, including maGSCs, ESCs, and iPSCs can become targets for CTLs, even if the expression level of MHC class I molecules is below the detection limit of flow cytometry. Thus they are not protected against CTL-mediated cytotoxicity. Therefore, pluripotent cells might be rejected after transplantation by this mechanism if specific antigens are presented and if specific activated CTLs are present. Our results show that the adaptive immune system has in principle the capacity to kill pluripotent and teratoma forming stem cells. This finding might help to develop new strategies to increase the safety of future transplantations of in vitro differentiated cells by exploiting a selective immune response against contaminating undifferentiated cells. Reviewers This article was reviewed by Bhagirath Singh, Etienne Joly and Lutz Walter. PMID:19715575

First steps to define murine amniotic fluid stem cell microenvironment.

PubMed

Bertin, E; Piccoli, M; Franzin, C; Spiro, G; Donà, S; Dedja, A; Schiavi, F; Taschin, E; Bonaldo, P; Braghetta, P; De Coppi, P; Pozzobon, M

2016-11-15

Stem cell niche refers to the microenvironment where stem cells reside in living organisms. Several elements define the niche and regulate stem cell characteristics, such as stromal support cells, gap junctions, soluble factors, extracellular matrix proteins, blood vessels and neural inputs. In the last years, different studies demonstrated the presence of cKit + cells in human and murine amniotic fluid, which have been defined as amniotic fluid stem (AFS) cells. Firstly, we characterized the murine cKit + cells present both in the amniotic fluid and in the amnion. Secondly, to analyze the AFS cell microenvironment, we injected murine YFP + embryonic stem cells (ESC) into the amniotic fluid of E13.5 wild type embryos. Four days after transplantation we found that YFP + sorted cells maintained the expression of pluripotency markers and that ESC adherent to the amnion were more similar to original ESC in respect to those isolated from the amniotic fluid. Moreover, cytokines evaluation and oxygen concentration analysis revealed in this microenvironment the presence of factors that are considered key regulators in stem cell niches. This is the first indication that AFS cells reside in a microenvironment that possess specific characteristics able to maintain stemness of resident and exogenous stem cells.

Development of bioengineering system for stem cell proliferation

NASA Astrophysics Data System (ADS)

Park, H. S.; Shah, R.; Shah, C.

2016-08-01

From last decades, intensive research in the field of stem cells proliferation had been promoted due to the unique property of stem cells to self-renew themselves into multiples and has potential to replicate into an organ or tissues and so it's highly demanding though challenging. Bioreactor, a mechanical device, works as a womb for stem cell proliferation by providing nutritious environment for the proper growth of stem cells. Various factors affecting stem cells growth are the bioreactor mechanism, feeding of continuous nutrients, healthy environment, etc., but it always remains a challenge for controlling biological parameters. The present paper unveils the design of mechanical device commonly known as bioreactor in tissues engineering and biotech field, use for proliferation of stem cells and imparts the proper growing condition for stem cells. This high functional bioreactor provides automation mixing of cell culture and stem cells. This design operates in conjunction with mechanism of reciprocating motion. Compare to commercial bioreactors, this proposed design is more convenient, easy to operate and less maintenance is required as bioreactor culture bag is made of polyethylene which is single use purpose. Development of this bioengineering system will be beneficial for better growth and expansion of stem cell

Bioenergetics mechanisms regulating muscle stem cell self-renewal commitment and function.

PubMed

Abreu, Phablo

2018-04-16

Muscle stem cells or satellite cells are crucial for muscle maintenance and repair. These cells are mitotically quiescent and uniformly express the transcription factor Pax7, intermittently entering the cell cycle to give rise to daughter myogenic precursors cells and fuse with neighboring myofibers or self-renew, replenishing the stem cell pool in adult skeletal muscle. Pivotal roles of muscle stem cells in muscle repair have been uncovered, but it still remains unclear how muscle stem cell self-renewal is molecularly regulated and how muscle stem cells maintain muscle tissue homeostasis. Defects in muscle stem cell regulation to maintain/return to quiescence and self-renew are observed in degenerative conditions such as aging and neuromuscular disease. Recent works has suggested the existence of metabolic regulation and mitochondrial alterations in muscle stem cells, influencing the self-renewal commitment and function. Here I present a brief overview of recent understanding of how metabolic reprogramming governs self-renewal commitment, which is essential for conservation of muscle satellite cell pools throughout life, as well as the implications for regenerative medicine. Copyright © 2018. Published by Elsevier Masson SAS.

Stem cell motility enables a density-dependent rate of fate commitment during scaled resizing of adult organs

NASA Astrophysics Data System (ADS)

Du, Xinxin; O'Brien, Lucy; Riedel-Kruse, Ingmar

Many adult organs grow or shrink to accommodate fluctuating levels of physiological demand. Specifically, the intestine of the fruit fly (the midgut) expands four-fold in the number of mature cells and, proportionally, the number of stem cells when the fly eats. However, the cellular behaviors that give rise to this stem scaling are not well-understood. Here we present a biophysical model of the adult fly midgut. A set of differential equations can recapitulate the physiological kinetics of cells during midgut growth and shrinkage as long as the rate of stem cell fate commitment depends on the stem cell number density in the tissue. To elucidate the source of this dependence, we model the tissue in a 2D simulation with soft spheres, where stem cells choose fate commitment through Delta-Notch pathway interactions with other stem cells, a known process in fly midguts. We find that as long as stem cells exhibit a large enough amplitude of random motion through the tissue (`stem cell motility'), and explore a large enough `territory' in their lifetime, stem cell scaling can occur. These model observations are confirmed through in vivo live-imaging, where we indeed see that stem cells are motile in the fly midgut.

Isolation and purification of rabbit mesenchymal stem cells using an optimized protocol.

PubMed

Lin, Chunbo; Shen, Maorong; Chen, Weiping; Li, Xiaofeng; Luo, Daoming; Cai, Jinhong; Yang, Yuan

2015-11-01

Mesenchymal stem cells were first isolated and grown in vitro by Friedenstein over 40 yr ago; however, their isolation remains challenging as they lack unique markers for identification and are present in very small quantities in mesenchymal tissues and bone marrow. Using whole marrow samples, common methods for mesenchymal stem cell isolation are the adhesion method and density gradient fractionation. The whole marrow sample adhesion method still results in the nonspecific isolation of mononuclear cells, and activation and/or potential loss of target cells. Density gradient fractionation methods are complicated, and may result in contamination with toxic substances that affect cell viability. In the present study, we developed an optimized protocol for the isolation and purification of mesenchymal stem cells based on the principles of hypotonic lysis and natural sedimentation.

Derivation of Multipotent Mesenchymal Precursors from Human Embryonic Stem Cells

PubMed Central

Barberi, Tiziano; Willis, Lucy M; Socci, Nicholas D; Studer, Lorenz

2005-01-01

Background Human embryonic stem cells provide access to the earliest stages of human development and may serve as a source of specialized cells for regenerative medicine. Thus, it becomes crucial to develop protocols for the directed differentiation of embryonic stem cells into tissue-restricted precursors. Methods and Findings Here, we present culture conditions for the derivation of unlimited numbers of pure mesenchymal precursors from human embryonic stem cells and demonstrate multilineage differentiation into fat, cartilage, bone, and skeletal muscle cells. Conclusion Our findings will help to elucidate the mechanism of mesoderm specification during embryonic stem cell differentiation and provide a platform to efficiently generate specialized human mesenchymal cell types for future clinical applications. PMID:15971941

Use of Pig as a Model for Mesenchymal Stem Cell Therapies for Bone Regeneration.

PubMed

Rubessa, Marcello; Polkoff, Kathryn; Bionaz, Massimo; Monaco, Elisa; Milner, Derek J; Holllister, Scott J; Goldwasser, Michael S; Wheeler, Matthew B

2017-10-02

Bone is a plastic tissue with a large healing capability. However, extensive bone loss due to disease or trauma requires extreme therapy such as bone grafting or tissue-engineering applications. Presently, bone grafting is the gold standard for bone repair, but presents serious limitations including donor site morbidity, rejection, and limited tissue regeneration. The use of stem cells appears to be a means to overcome such limitations. Bone marrow mesenchymal stem cells (BMSC) have been the choice thus far for stem cell therapy for bone regeneration. However, adipose-derived stem cells (ASC) have similar immunophenotype, morphology, multilineage potential, and transcriptome compared to BMSC, and both types have demonstrated extensive osteogenic capacity both in vitro and in vivo in several species. The use of scaffolds in combination with stem cells and growth factors provides a valuable tool for guided bone regeneration, especially for complex anatomic defects. Before translation to human medicine, regenerative strategies must be developed in animal models to improve effectiveness and efficiency. The pig presents as a useful model due to similar macro- and microanatomy and favorable logistics of use. This review examines data that provides strong support for the clinical translation of the pig model for bone regeneration.

A Method to Identify and Isolate Pluripotent Human Stem Cells and Mouse Epiblast Stem Cells Using Lipid Body-Associated Retinyl Ester Fluorescence

PubMed Central

Muthusamy, Thangaselvam; Mukherjee, Odity; Menon, Radhika; Megha, P.B.; Panicker, Mitradas M.

2014-01-01

Summary We describe the use of a characteristic blue fluorescence to identify and isolate pluripotent human embryonic stem cells and human-induced pluripotent stem cells. The blue fluorescence emission (450–500 nm) is readily observed by fluorescence microscopy and correlates with the expression of pluripotency markers (OCT4, SOX2, and NANOG). It allows easy identification and isolation of undifferentiated human pluripotent stem cells, high-throughput fluorescence sorting and subsequent propagation. The fluorescence appears early during somatic reprogramming. We show that the blue fluorescence arises from the sequestration of retinyl esters in cytoplasmic lipid bodies. The retinoid-sequestering lipid bodies are specific to human and mouse pluripotent stem cells of the primed or epiblast-like state and absent in naive mouse embryonic stem cells. Retinol, present in widely used stem cell culture media, is sequestered as retinyl ester specifically by primed pluripotent cells and also can induce the formation of these lipid bodies. PMID:25068130

'New embryos' - new challenges for the ethics of stem cell research.

PubMed

Holm, Søren

2008-01-01

Among the many ethical issues raised by human embryonic stem cell research (in the following all references to 'stem cells' should be read as references to human embryonic stem cells), two have gained specific prominence: (1) whether stem cell research is ethically problematic because it entails the destruction of human embryos and (2) what kind of control embryo donors should have over the stem cell lines derived from their embryos. In the present paper, I will analyse how these two issues are engaged by various attempts to derive stem cells from anomalous embryos (e.g. embryos in cleavage arrest, embryos not implanted following pre-implantation genetic diagnosis or embryos created by altered nuclear transfer) or in ways that are claimed to be non-destructive for the embryo (e.g. blastocyst or blastomere biopsy). Copyright 2008 S. Karger AG, Basel.

Does the preference of peripheral versus central venous access in peripheral blood stem cell collection/yield change stem cell kinetics in autologous stem cell transplantation?

PubMed

Dogu, Mehmet Hilmi; Kaya, Ali Hakan; Berber, Ilhami; Sari, İsmail; Tekgündüz, Emre; Erkurt, Mehmet Ali; Iskender, Dicle; Kayıkçı, Ömur; Kuku, Irfan; Kaya, Emin; Keskin, Ali; Altuntaş, Fevzi

2016-02-01

Central venous access is often used during apheresis procedure in stem cell collection. The aim of the present study was to evaluate whether central or peripheral venous access has an effect on stem cell yield and the kinetics of the procedure and the product in patients undergoing ASCT after high dose therapy. A total of 327 patients were retrospectively reviewed. The use of peripheral venous access for stem cell yield was significantly more frequent in males compared to females (p = 0.005). Total volume of the product was significantly lower in central venous access group (p = 0.046). As being a less invasive procedure, peripheral venous access can be used for stem cell yield in eligible selected patients. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Development of Stem Cell-Based Treatment for Liver Failure.

PubMed

Zhu, Tiantian; Li, Yuwen; Guo, Yusheng; Zhu, Chuanlong

2017-01-01

Liver failure is a devastating clinical syndrome with a persistently mortality rate despite advanced care. Orthotopic liver transplantation protected patients from hepatic failure. Yet, limitations including postoperative complications, high costs, and shortages of donor organs defect its application. The development of stem cell therapy complements the deficiencies of liver transplantation, due to the inherent ability of stem cells to proliferate and differentiate. Understand the source of stem cells, as well as the advantages and disadvantages of stem cell therapy. Based on published papers, we discussed the cell sources and therapeutic effect of stem cells. We also summarized the pros and cons, as well as optimization of stem cell-based treatment. Finally outlook future prospects of stem cell therapy. Stem cells may be harvested from a variety of human tissues, and then used to promote the convalescence of hepatocellular function. The emergence of the co-cultured system, tissueengineered technology and genetic modfication has further enhanced the functionality of stem cells. However, the tumorigenicity, the low survival rate and the scarcity of long-term treatment effect are obstacles for the further development of stem cell therapy. In this review, we highlight current research findings and present the future prospects in the area of stem cell-based treatment for liver failure. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Recovery of CD45(-)/Lin(-)/SSEA-4(+) very small embryonic-like stem cells by cord blood bank standard operating procedures.

PubMed

Chang, Yu-Jen; Tien, Kuei-Erh; Wen, Cheng-Hao; Hsieh, Tzu-Bou; Hwang, Shiaw-Min

2014-04-01

Very small embryonic-like (VSEL) stem cells are a rare cell population present in bone marrow, cord blood and other tissues that displays a distinct small cell size and the ability to give rise to cells of the three germ layers. VSEL stem cells were reported to be discarded in the red blood cell fraction by Ficoll-Paque density gradient centrifugation during the processing of bone marrow and cord blood specimens. However, most cord blood banks do not include density gradient centrifugation in their procedures while red blood cells are removed by Hespan sedimentation following the Cord Blood Transplantation Study cord blood bank standard operating procedures (COBLT SOP). To clarify the retention of VSEL stem cells, we investigated the recovery of VSEL stem cells following COBLT SOP guidelines. The recovery of CD45(-)/Lin(-)/SSEA-4(+) VSEL stem cells of umbilical cord blood was examined by flow cytometry before and after COBLT SOP processing, and relative expression of pluripotent genes was analyzed by quantitative polymerase chain reaction. CD45(-)/Lin(-)/SSEA-4(+) VSEL stem cells were mostly recovered in the final products following COBLT SOP guidelines. The expression of pluripotent genes could be maintained at >80% in products after hetastarch (Hespan; B. Braun Medical Inc., Irvine, CA, USA) processing. The rare sub-population of CD45(-)/Lin(-)/SSEA-4(+) VSEL stem cells survived after Hespan sedimentation. This finding suggests that umbilical cord blood units cryopreserved by COBLT SOP in cord blood banks should retain most VSEL stem cells present in the un-processed specimens. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Production of urothelium from pluripotent stem cells for regenerative applications.

PubMed

Osborn, Stephanie L; Kurzrock, Eric A

2015-01-01

As bladder reconstruction strategies evolve, a feasible and safe source of transplantable urothelium becomes a major consideration for patients with advanced bladder disease, particularly cancer. Pluripotent stem cells, such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), are attractive candidates from which to derive urothelium as they renew and proliferate indefinitely in vitro and fulfill the non-autologous and/or non-urologic criteria, respectively, that is required for many patients. This review presents the latest advancements in differentiating urothelium from pluripotent stem cells in vitro in the context of current bladder tissue engineering strategies.

Stem cell research: cloning, therapy and scientific fraud.

PubMed

Rusnak, A J; Chudley, A E

2006-10-01

Stem cell research has generated intense excitement, awareness, and debate. Events in the 2005-2006 saw the rise and fall of a South Korean scientist who had claimed to be the first to clone a human embryonic stem cell line. From celebration of the potential use of stem cells in the treatment of human disease to disciplinary action taken against the disgraced scientists, the drama has unfolded throughout the world media. Prompted by an image of therapeutic cloning presented on a South Korean stamp, a brief review of stem cell research and the events of the Woo-suk Hwang scandal are discussed.

Isolation and functional interrogation of adult human prostate epithelial stem cells at single cell resolution.

PubMed

Hu, Wen-Yang; Hu, Dan-Ping; Xie, Lishi; Li, Ye; Majumdar, Shyama; Nonn, Larisa; Hu, Hong; Shioda, Toshi; Prins, Gail S

2017-08-01

Using primary cultures of normal human prostate epithelial cells, we developed a novel prostasphere-based, label-retention assay that permits identification and isolation of stem cells at a single cell level. Their bona fide stem cell nature was corroborated using in vitro and in vivo regenerative assays and documentation of symmetric/asymmetric division. Robust WNT10B and KRT13 levels without E-cadherin or KRT14 staining distinguished individual stem cells from daughter progenitors in spheroids. Following FACS to isolate label-retaining stem cells from label-free progenitors, RNA-seq identified unique gene signatures for the separate populations which may serve as useful biomarkers. Knockdown of KRT13 or PRAC1 reduced sphere formation and symmetric self-renewal highlighting their role in stem cell maintenance. Pathways analysis identified ribosome biogenesis and membrane estrogen-receptor signaling enriched in stem cells with NF-ĸB signaling enriched in progenitors; activities that were biologically confirmed. Further, bioassays identified heightened autophagy flux and reduced metabolism in stem cells relative to progenitors. These approaches similarly identified stem-like cells from prostate cancer specimens and prostate, breast and colon cancer cell lines suggesting wide applicability. Together, the present studies isolate and identify unique characteristics of normal human prostate stem cells and uncover processes that maintain stem cell homeostasis in the prostate gland. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Gastric cancer stem cells: A novel therapeutic target

PubMed Central

Singh, Shree Ram

2013-01-01

Gastric cancer remains one of the leading causes of global cancer mortality. Multipotent gastric stem cells have been identified in both mouse and human stomachs, and they play an essential role in the self-renewal and homeostasis of gastric mucosa. There are several environmental and genetic factors known to promote gastric cancer. In recent years, numerous in vitro and in vivo studies suggest that gastric cancer may originate from normal stem cells or bone marrow–derived mesenchymal cells, and that gastric tumors contain cancer stem cells. Cancer stem cells are believed to share a common microenvironment with normal niche, which play an important role in gastric cancer and tumor growth. This mini-review presents a brief overview of the recent developments in gastric cancer stem cell research. The knowledge gained by studying cancer stem cells in gastric mucosa will support the development of novel therapeutic strategies for gastric cancer. PMID:23583679

Isolation and evaluation of dental pulp stem cells from teeth with advanced periodontal disease.

PubMed

Derakhshani, Ali; Raoof, Maryam; Dabiri, Shahriar; Farsinejad, Ali Reza; Gorjestani, Hedayat; Yaghoobi, Mohammad Mehdi; Shokouhinejad, Noushin; Ehsani, Maryam

2015-04-01

Successful isolation of mesenchymal stem cells from waste tissues might be extremely promising for developing stem cell-based therapies. This study aimed to explore whether cells retrieved from teeth extracted due to advanced periodontal disease present mesenchymal stem cell-like properties. Pulp cells were isolated from 15 intact molars and 15 teeth with advanced periodontal disease. Cell proliferation and markers of mesenchymal stem cells were evaluated. Based on the RT-PCR and agarose gel electrophoresis, nucleostemin, Oct-4 and jmj2c, but not Nanog, were expressed in undifferentiated mesenchymal stem cells of both groups. Interestingly, diseased pulp exhibited higher gene expressions although it was not statistically significant. The average percentage of BrdU positive cells in the diseased group (84.4%, n = 5) was significantly higher than that of the control group (65.4%, n = 5) (t-test, P = 0.001). Our results indicate the successful isolation of mesenchymal stem cells from the pulp tissue of hopeless periodontally involved teeth.

Evidence of Mobilization of Pluripotent Stem Cells into Peripheral Blood of Patients with Myocardial Ischemia

PubMed Central

Abdel-Latif, Ahmed; Zuba-Surma, Ewa K.; Ziada, Khaled M.; Kucia, Magdalena; Cohen, Donald A.; Kaplan, Alan M.; Zant, Gary Van; Selim, Samy; Smyth, Susan S.; Ratajczak, Mariusz Z.

2010-01-01

Objective The ischemic myocardium releases multiple chemotactic factors responsible for the mobilization and recruitment of bone marrow-derived cells to injured myocardium. However, the mobilization of primitive pluripotent stem cells (PSCs) enriched in Very Small Embryonic-Like stem cells (VSELs) in various cardiac ischemic scenarios is not well understood. Methods Fifty four ischemic heart disease patients, including subjects with stable angina, non-ST elevation (NSTME) myocardial infarction (MI) and ST elevation myocardial infarction (STEMI), and twelve matched controls were enrolled. The absolute numbers of circulating stem/primitive cells in samples of peripheral blood (PB) were quantitated by Image Stream Analysis and conventional flow cytometry. Gene expression of PSC (Oct-4 and Nanog), early cardiomyocyte (Nkx-2.5 and GATA-4), and endothelial (vWF) markers was analyzed by real-time PCR. Results The absolute numbers of PSCs, stem cell populations enriched in VSELs and hematopoietic stem cells (HSCs) present in PB were significantly higher in STEMI patients at presentation and declined over time. There was a corresponding increase in pluripotent, cardiac and endothelial gene expression in unfractionated PB cells and sorted PB-derived primitive CD34+ cells. The absolute numbers of circulating VSELs and HSCs in STEMI correlated negatively with patients' age. Conclusions Myocardial ischemia mobilizes primitive PSCs including pluripotent VSELs into the circulation. The peak of mobilization occurs within 12 hours in patients presenting with STEMI, which may represent a therapeutic window for future clinical applications. Reduced stem cell mobilization with advancing age could explain, in part, the observation that age is associated with poor prognosis in patients with MI. PMID:20800644

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

PubMed

Houbracken, Isabelle; Bouwens, Luc

2010-01-01

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

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

PubMed

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

2005-01-01

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

Fetal stem cell transplantation: Past, present, and future

PubMed Central

Ishii, Tetsuya; Eto, Koji

2014-01-01

Since 1928, human fetal tissues and stem cells have been used worldwide to treat various conditions. Although the transplantation of the fetal midbrain substantia nigra and dopaminergic neurons in patients suffering from Parkinson’s disease is particularly noteworthy, the history of other types of grafts, such as those of the fetal liver, thymus, and pancreas, should be addressed as there are many lessons to be learnt for future stem cell transplantation. This report describes previous practices and complications that led to current clinical trials of isolated fetal stem cells and embryonic stem (ES) cells. Moreover, strategies for transplantation are considered, with a particular focus on donor cells, cell processing, and the therapeutic cell niche, in addition to ethical issues associated with fetal origin. With the advent of autologous induced pluripotent stem cells and ES cells, clinical dependence on fetal transplantation is expected to gradually decline due to lasting ethical controversies, despite landmark achievements. PMID:25258662

Stem cell regenerative potential for plastic and reconstructive surgery.

PubMed

Boháč, Martin; Csöbönyeiová, Mária; Kupcová, Ida; Zamborský, Radoslav; Fedeleš, Jozef; Koller, Ján

2016-12-01

Stem cells represent heterogeneous population of undifferentiated cells with unique characteristics of long term self renewal and plasticity. Moreover, they are capable of active migration to diseased tissues, secretion of different bioactive molecules, and they have immunosuppressive potential as well. They occur in all tissues through life and are involved in process of embryogenesis and regeneration. During last decades stem cells attracted significant attention in each field of medicine, including plastic and reconstructive surgery. The main goal of the present review article is to present and discuss the potential of stem cells and to provide information about their safe utilization in chronic wounds and fistulae healing, scar management, breast reconstruction, as well as in bone, tendon and peripheral nerve regeneration.

Epithelial-mesenchymal transition transcription factors control pluripotent adult stem cell migration in vivo in planarians.

PubMed

Abnave, Prasad; Aboukhatwa, Ellen; Kosaka, Nobuyoshi; Thompson, James; Hill, Mark A; Aboobaker, A Aziz

2017-10-01

Migration of stem cells underpins the physiology of metazoan animals. For tissues to be maintained, stem cells and their progeny must migrate and differentiate in the correct positions. This need is even more acute after tissue damage by wounding or pathogenic infection. Inappropriate migration also underpins metastasis. Despite this, few mechanistic studies address stem cell migration during repair or homeostasis in adult tissues. Here, we present a shielded X-ray irradiation assay that allows us to follow stem cell migration in planarians. We demonstrate the use of this system to study the molecular control of stem cell migration and show that snail-1 , snail-2 and zeb-1 EMT transcription factor homologs are necessary for cell migration to wound sites and for the establishment of migratory cell morphology. We also observed that stem cells undergo homeostatic migration to anterior regions that lack local stem cells, in the absence of injury, maintaining tissue homeostasis. This requires the polarity determinant notum Our work establishes planarians as a suitable model for further in-depth study of the processes controlling stem cell migration in vivo . © 2017. Published by The Company of Biologists Ltd.

Hematopoietic stem cells: can old cells learn new tricks?

PubMed

Ho, Anthony D; Punzel, Michael

2003-05-01

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

Professional Regulation: A Potentially Valuable Tool in Responding to “Stem Cell Tourism”

PubMed Central

Zarzeczny, Amy; Caulfield, Timothy; Ogbogu, Ubaka; Bell, Peter; Crooks, Valorie A.; Kamenova, Kalina; Master, Zubin; Rachul, Christen; Snyder, Jeremy; Toews, Maeghan; Zoeller, Sonja

2014-01-01

The growing international market for unproven stem cell-based interventions advertised on a direct-to-consumer basis over the internet (“stem cell tourism”) is a source of concern because of the risks it presents to patients as well as their supporters, domestic health care systems, and the stem cell research field. Emerging responses such as public and health provider-focused education and national regulatory efforts are encouraging, but the market continues to grow. Physicians play a number of roles in the stem cell tourism market and, in many jurisdictions, are members of a regulated profession. In this article, we consider the use of professional regulation to address physician involvement in stem cell tourism. Although it is not without its limitations, professional regulation is a potentially valuable tool that can be employed in response to problematic types of physician involvement in the stem cell tourism market. PMID:25241736

The (not so) immortal strand hypothesis.

PubMed

Tomasetti, Cristian; Bozic, Ivana

2015-03-01

Non-random segregation of DNA strands during stem cell replication has been proposed as a mechanism to minimize accumulated genetic errors in stem cells of rapidly dividing tissues. According to this hypothesis, an "immortal" DNA strand is passed to the stem cell daughter and not the more differentiated cell, keeping the stem cell lineage replication error-free. After it was introduced, experimental evidence both in favor and against the hypothesis has been presented. Using a novel methodology that utilizes cancer sequencing data we are able to estimate the rate of accumulation of mutations in healthy stem cells of the colon, blood and head and neck tissues. We find that in these tissues mutations in stem cells accumulate at rates strikingly similar to those expected without the protection from the immortal strand mechanism. Utilizing an approach that is fundamentally different from previous efforts to confirm or refute the immortal strand hypothesis, we provide evidence against non-random segregation of DNA during stem cell replication. Our results strongly suggest that parental DNA is passed randomly to stem cell daughters and provides new insight into the mechanism of DNA replication in stem cells. Copyright © 2015. Published by Elsevier B.V.

The (not so) Immortal Strand Hypothesis

PubMed Central

Tomasetti, Cristian; Bozic, Ivana

2015-01-01

Background Non-random segregation of DNA strands during stem cell replication has been proposed as a mechanism to minimize accumulated genetic errors in stem cells of rapidly dividing tissues. According to this hypothesis, an “immortal” DNA strand is passed to the stem cell daughter and not the more differentiated cell, keeping the stem cell lineage replication error-free. After it was introduced, experimental evidence both in favor and against the hypothesis has been presented. Principal Findings Using a novel methodology that utilizes cancer sequencing data we are able to estimate the rate of accumulation of mutations in healthy stem cells of the colon, blood and head and neck tissues. We to find that in these tissues mutations in stem cells accumulate at rates strikingly similar to those expected without the protection from the immortal strand mechanism. Significance Utilizing an approach that is fundamentally different from previous efforts to confirm or refute the immortal strand hypothesis, we provide strong evidence against non-random segregation of DNA during stem cell replication. Our results strongly suggest that parental DNA is passed randomly to stem cell daughters and provides new insight into the mechanism of DNA replication in stem cells. PMID:25700960

Analysis of Neural Stem Cells from Human Cortical Brain Structures In Vitro.

PubMed

Aleksandrova, M A; Poltavtseva, R A; Marei, M V; Sukhikh, G T

2016-05-01

Comparative immunohistochemical analysis of the neocortex from human fetuses showed that neural stem and progenitor cells are present in the brain throughout the gestation period, at least from week 8 through 26. At the same time, neural stem cells from the first and second trimester fetuses differed by the distribution, morphology, growth, and quantity. Immunocytochemical analysis of neural stem cells derived from fetuses at different gestation terms and cultured under different conditions showed their differentiation capacity. Detailed analysis of neural stem cell populations derived from fetuses on gestation weeks 8-9, 18-20, and 26 expressing Lex/SSEA1 was performed.

Oral epithelial stem cells – implications in normal development and cancer metastasis

PubMed Central

Papagerakis, Silvana; Pannone, Giuseppe; Zheng, Li; About, Imad; Taqi, Nawar; Nguyen, Nghia P.T.; Matossian, Margarite; McAlpin, Blake; Santoro, Angela; McHugh, Jonathan; Prince, Mark E.; Papagerakis, Petros

2014-01-01

Oral mucosa is continuously exposed to environmental forces and has to be constantly renewed. Accordingly, the oral mucosa epithelium contains a large reservoir of epithelial stem cells necessary for tissue homeostasis. Despite considerable scientific advances in stem cell behavior in a number of tissues, fewer studies have been devoted to the stem cells in the oral epithelium. Most of oral mucosa stem cells studies are focused on identifying cancer stem cells (CSC) in oral squamous cell carcinomas (OSCCs) among other head and neck cancers. OSCCs are the most prevalent epithelial tumors of the head and neck region, marked by their aggressiveness and invasiveness. Due to their highly tumorigenic properties, it has been suggested that CSC may be the critical population of cancer cells in the development of OSCC metastasis. This review presents a brief overview of epithelium stem cells with implications in oral health, and the clinical implications of the CSC concept in OSCC metastatic dissemination. PMID:24803391

Lenses for Framing Decisions: Undergraduates' Decision Making about Stem Cell Research

ERIC Educational Resources Information Center

Halverson, Kristy Lynn; Siegel, Marcelle A.; Freyermuth, Sharyn K.

2009-01-01

Decision making is influenced by multiple factors, especially when approaching controversial socio-scientific issues, such as stem cell research. In the present study, we used qualitative data from 132 college student papers in a biotechnology course to investigate how students made decisions about stem cell research issues. Students indicated…

Pluripotent Stem Cells as a Robust Source of Mesenchymal Stem Cells.

PubMed

Luzzani, Carlos D; Miriuka, Santiago G

2017-02-01

Mesenchymal stem cells (MSC) have been extensively studied over the past years for the treatment of different diseases. Most of the ongoing clinical trials currently involve the use of MSC derived from adult tissues. This source may have some limitations, particularly with therapies that may require extensive and repetitive cell dosage. However, nowadays, there is a staggering growth in literature on a new source of MSC. There is now increasing evidence about the mesenchymal differentiation from pluripotent stem cell (PSC). Here, we summarize the current knowledge of pluripotent-derived mesenchymal stem cells (PD-MSC). We present a historical perspective on the subject, and then discuss some critical questions that remain unanswered.

Stem cell transplantation (cord blood transplants).

PubMed

Chao, Nelson J; Emerson, Stephen G; Weinberg, Kenneth I

2004-01-01

Allogeneic stem cell transplantation is an accepted treatment modality for selected malignant and non-malignant diseases. However, the ability to identify suitably matched related or unrelated donors can be difficult in some patients. Alternative sources of stem cells such as cord blood provide a readily available graft for such patients. Data accumulated over the past several years have demonstrated that the use of cord blood is an accepted source of stem cells for pediatric patients. Since the cell numbers of hematopoietic progenitors in cord blood is limited and the collection can occur only in a single occasion, its use in adult patients can be more problematic. Here, new developments in the use of cord blood for adults and studies aimed at expansion of cord blood cells and immune reconstitution are described. In Section I, Dr. Nelson Chao describes the early data in cord blood transplantation in adult patients. The patient outcomes are reviewed and analyzed for various factors such as cell dose, HLA typing, and patient selection that could have contributed to the final outcome of these adult patients. Myeloablative as well as nonmyeloablative approaches are presented. Discussion of the various benefits and risks are presented. More recent data from multiple single institutions as well as larger registry data comparisons are also provided. Analyses of these studies suggest methods to improve on the outcome. These newer data should lead to a logical progression in the use of cord blood cells in adult patients. In Section II, Dr. Stephen Emerson describes the historical efforts associated with expansion of hematopoietic stem cells, specifically with cord blood cells. These efforts to expand cord blood cells continue with novel methods. Moreover, a better understanding of stem cell biology and signaling is critical if we are to be able to effectively expand these cells for clinical use. An alternative, more direct, approach to expanding stem cells could be achieved by specific genetic pathways known or believed to support primitive HSC proliferation such as Notch-1 receptor activation, Wnt/LEF-1 pathway induction, telomerase or the Homeobox (Hox) gene products. The clinical experience with the use of expanded cord blood cells is also discussed. In Section III, Dr. Kenneth Weinberg describes immune reconstitution or lack thereof following cord blood transplantation. One of the hallmarks of successful hematopoietic stem cell transplantation is the ability to fully reconstitute the immune system of the recipient. Thus, the relationship between stem cell source and the development of T lymphocyte functions required for protection of the recipient from infection will be described, and cord blood recipients will be compared with those receiving other sources of stem cells. T cell development is described in detail, tracking from prethymic to postthymic lymphocytes with specific attention to umbilical cord blood as the source of stem cells. Moreover, a discussion of the placenta as a special microenvironment for umbilical cord blood is presented. Strategies to overcome the immunological defects are presented to improve the outcome of these recipients.

Adenovirus-mediated truncated Bid overexpression induced by the Cre/LoxP system promotes the cell apoptosis of CD133+ ovarian cancer stem cells.

PubMed

Long, Qifang; Yang, Ru; Lu, Weixian; Zhu, Weipei; Zhou, Jundong; Zheng, Cui; Zhou, Dongmei; Yu, Ling; Wu, Jinchang

2017-01-01

Cancer stem cells are a small subset of cancer cells that contribute to cancer progression, metastasis, chemoresistance and recurrence. CD133-positive (CD133+) ovarian cancer cells have been identified as ovarian cancer stem cells. Adenovirus-mediated gene therapy is an innovative therapeutic method for cancer treatment. In the present study, we aimed to develop a new gene therapy to specifically eliminate CD133+ ovarian cancer stem cells by targeting CD133. We used the Cre/LoxP system to augment the selective expression of the truncated Bid (tBid) gene as suicide gene therapy in CD133+ ovarian cancer stem cells. The adenovirus (Ad)-CD133-Cre expressing Cre recombinase under the control of the CD133 promoter and Ad-CMV-LoxP-Neo-LoxP-tBid expressing tBid under the control of the CMV promoter were successfully constructed using the Cre/LoxP switching system. The co-infection of Ad-CMV-LoxP-Neo-LoxP-tBid and Ad-CD133-Cre selectively induced tBid overexpression, which inhibited cell growth and triggered the cell apoptosis of CD133+ ovarian cancer stem cells. The Cre/LoxP system-mediated tBid overexpression activated the pro-apoptotic signaling pathway and augmented the cytotoxic effect of cisplatin in CD133+ ovarian cancer stem cells. Furthermore, in xenograft experiments, co-infection with the two recombinant adenoviruses markedly suppressed tumor growth in vivo and promoted cell apoptosis in tumor tissues. Taken together, the present study provides evidence that the adenovirus-mediated tBid overexpression induced by the Cre/LoxP system can effectively eliminate CD133+ ovarian cancer stem cells, representing a novel therapeutic strategy for the treatment of ovarian cancer.

Stem Cell-based Tissue Engineering Approaches for Musculoskeletal Regeneration

PubMed Central

Brown, Patrick T.; Handorf, Andrew M.; Jeon, Won Bae; Li, Wan-Ju

2014-01-01

The field of regenerative medicine and tissue engineering is an ever evolving field that holds promise in treating numerous musculoskeletal diseases and injuries. An important impetus in the development of the field was the discovery and implementation of stem cells. The utilization of mesenchymal stem cells, and later embryonic and induced pluripotent stem cells, opens new arenas for tissue engineering and presents the potential of developing stem cell-based therapies for disease treatment. Multipotent and pluripotent stem cells can produce various lineage tissues, and allow for derivation of a tissue that may be comprised of multiple cell types. As the field grows, the combination of biomaterial scaffolds and bioreactors provides methods to create an environment for stem cells that better represent their microenvironment for new tissue formation. As technologies for the fabrication of biomaterial scaffolds advance, the ability of scaffolds to modulate stem cell behavior advances as well. The composition of scaffolds could be of natural or synthetic materials and could be tailored to enhance cell self-renewal and/or direct cell fates. In addition to biomaterial scaffolds, studies of tissue development and cellular microenvironments have determined other factors, such as growth factors and oxygen tension, that are crucial to the regulation of stem cell activity. The overarching goal of stem cell-based tissue engineering research is to precisely control differentiation of stem cells in culture. In this article, we review current developments in tissue engineering, focusing on several stem cell sources, induction factors including growth factors, oxygen tension, biomaterials, and mechanical stimulation, and the internal and external regulatory mechanisms that govern proliferation and differentiation. PMID:23432679

Stem Cells for Skeletal Muscle Tissue Engineering.

PubMed

Pantelic, Molly N; Larkin, Lisa M

2018-04-19

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

Seeing Stem Cells at Work In Vivo

PubMed Central

Srivastava, Amit K.; Bulte, Jeff W. M.

2013-01-01

Stem cell based-therapies are novel therapeutic strategies that hold key for developing new treatments for diseases conditions with very few or no cures. Although there has been an increase in the number of clinical trials involving stem cell-based therapies in the last few years, the long-term risks and benefits of these therapies are still unknown. Detailed in vivo studies are needed to monitor the fate of transplanted cells, including their distribution, differentiation, and longevity over time. Advancements in non-invasive cellular imaging techniques to track engrafted cells in real-time present a powerful tool for determining the efficacy of stem cell-based therapies. In this review, we describe the latest approaches to stem cell labeling and tracking using different imaging modalities. PMID:23975604

Mesenchymal Stem Cells Improve Motor Functions and Decrease Neurodegeneration in Ataxic Mice

PubMed Central

Jones, Jonathan; Estirado, Alicia; Redondo, Carolina; Pacheco-Torres, Jesus; Sirerol-Piquer, Maria-Salomé; Garcia-Verdugo, José M; Martinez, Salvador

2015-01-01

The main objective of this work is to demonstrate the feasibility of using bone marrow-derived stem cells in treating a neurodegenerative disorder such as Friedreich's ataxia. In this disease, the dorsal root ganglia of the spinal cord are the first to degenerate. Two groups of mice were injected intrathecally with mesenchymal stem cells isolated from either wild-type or Fxntm1Mkn/Tg(FXN)YG8Pook (YG8) mice. As a result, both groups presented improved motor skills compared to nontreated mice. Also, frataxin expression was increased in the dorsal root ganglia of the treated groups, along with lower expression of the apoptotic markers analyzed. Furthermore, the injected stem cells expressed the trophic factors NT3, NT4, and BDNF, which bind to sensory neurons of the dorsal root ganglia and increase their survival. The expression of antioxidant enzymes indicated that the stem cell-treated mice presented higher levels of catalase and GPX-1, which are downregulated in the YG8 mice. There were no significant differences in the use of stem cells isolated from wild-type and YG8 mice. In conclusion, bone marrow mesenchymal stem cell transplantation, both autologous and allogeneic, is a feasible therapeutic option to consider in delaying the neurodegeneration observed in the dorsal root ganglia of Friedreich's ataxia patients. PMID:25070719

Mesenchymal stem cell's secretome promotes selective enrichment of cancer stem-like cells with specific cytogenetic profile.

PubMed

Jiménez, Gema; Hackenberg, Michael; Catalina, Purificación; Boulaiz, Houria; Griñán-Lisón, Carmen; García, María Ángel; Perán, Macarena; López-Ruiz, Elena; Ramírez, Alberto; Morata-Tarifa, Cynthia; Carrasco, Esther; Aguilera, Margarita; Marchal, Juan Antonio

2018-08-10

Cancer stem cells (CSCs) are responsible for tumor initiation, metastasis and cancer recurrence, however the involvement of microenvironment is crucial. Here, we have analyzed how human mesenchymal stem cells (MSCs)-derived conditioned medium (CM) affect colon and melanoma CSCs enrichment and maintenance. Our results strongly suggest that the secretome of CM-MSCs selects and maintains subpopulations with high expression of CSCs markers and ALDH1 activity, low proliferation rates with G1 phase arrest, and notably retain in vivo these properties. Cytogenetic analyses indicated that CM-cultured cells contain alterations in chromosome 17 (17q25). Subsequent SKY-FISH analyses suggested that genes located in 17q25 might be involved in stem-cell maintenance. The characterization of secreted proteins present in CM-MSCs revealed that four cytokines and seven growth factors are directly linked to the CSCs enrichment reported in this study. Further analyses revealed that the combination of just IL6 and HGF is enough to provide cancer cells with better stemness properties. In conclusion, this study demonstrates how specific chromosomal alterations present in CSCs subpopulations might represent an advantage for their in vitro maintenance and in vivo stemness properties. Copyright © 2018 Elsevier B.V. All rights reserved.

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

PubMed Central

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

2010-01-01

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

Characterization of rabbit limbal epithelial side population cells using RNA sequencing and single-cell qRT-PCR.

PubMed

Kameishi, Sumako; Umemoto, Terumasa; Matsuzaki, Yu; Fujita, Masako; Okano, Teruo; Kato, Takashi; Yamato, Masayuki

2016-05-06

Corneal epithelial stem cells reside in the limbus, a transitional zone between the cornea and conjunctiva, and are essential for maintaining homeostasis in the corneal epithelium. Although our previous studies demonstrated that rabbit limbal epithelial side population (SP) cells exhibit stem cell-like phenotypes with Hoechst 33342 staining, the different characteristics and/or populations of these cells remain unclear. Therefore, in this study, we determined the gene expression profiles of limbal epithelial SP cells by RNA sequencing using not only present public databases but also contigs that were created by de novo transcriptome assembly as references for mapping. Our transcriptome data indicated that limbal epithelial SP cells exhibited a stem cell-like phenotype compared with non-SP cells. Importantly, gene ontology analysis following RNA sequencing demonstrated that limbal epithelial SP cells exhibited significantly enhanced expression of mesenchymal/endothelial cell markers rather than epithelial cell markers. Furthermore, single-cell quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) demonstrated that the limbal epithelial SP population consisted of at least two immature cell populations with endothelial- or mesenchymal-like phenotypes. Therefore, our present results may propose the presence of a novel population of corneal epithelial stem cells distinct from conventional epithelial stem cells. Copyright © 2015 Elsevier Inc. All rights reserved.

s-SHIP expression identifies a subset of murine basal prostate cells as neonatal stem cells

PubMed Central

Brocqueville, Guillaume; Chmelar, Renee S.; Bauderlique-Le Roy, Hélène; Deruy, Emeric; Tian, Lu; Vessella, Robert L.; Greenberg, Norman M.; Bourette, Roland P.

2016-01-01

Isolation of prostate stem cells (PSCs) is crucial for understanding their biology during normal development and tumorigenesis. In this aim, we used a transgenic mouse model expressing GFP from the stem cell-specific s-SHIP promoter to mark putative stem cells during postnatal prostate development. Here we show that cells identified by GFP expression are present transiently during early prostate development and localize to the basal cell layer of the epithelium. These prostate GFP+ cells are a subpopulation of the Lin− CD24+ Sca-1+ CD49f+ cells and are capable of self-renewal together with enhanced growth potential in sphere-forming assay in vitro, a phenotype consistent with that of a PSC population. Transplantation assays of prostate GFP+ cells demonstrate reconstitution of prostate ducts containing both basal and luminal cells in renal grafts. Altogether, these results demonstrate that s-SHIP promoter expression is a new marker for neonatal basal prostate cells exhibiting stem cell properties that enables PSCs in situ identification and isolation via a single consistent parameter. Transcriptional profiling of these GFP+ neonatal stem cells showed an increased expression of several components of the Wnt signaling pathway. It also identified stem cell regulators with potential applications for further analyses of normal and cancer stem cells. PMID:27081082

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

PubMed Central

Alibardi, Lorenzo

2015-01-01

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

Effects of irradiation on stem cell response to differentiation inhibitors in the Planarian Dugesia etrusca

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

Steele, V.E.; Lange, C.S.

1976-07-01

The planarian owes its extensive powers of regeneration to the possession of a totipotential stem cell system. The survival of the animal after irradiation depends mainly upon this system. In this respect the planarian is analogous to mammalian organ systems such as bone marrow or gut epithelium. The differentiated cells control the course of stem cell mediated tissue renewal by the secretion of differentiator and/or inhibitor substances. One such inhibitor substance, present in extracts prepared from homogenized whole planarians, specifically inhibits brain formation. This substance is organ specific, but not species specific. The differentiative integrity of the stem cells aftermore » irradiation is measured by comparing the regenerated brain volumes resulting from the presence or absence of the brain inhibitory extract during the regeneration period. Our data suggest that increasing doses of x irradiation decreases the ability of the stem cells to respond to differentiative substances. The data presented also explore the possibility of altering the postirradiation recovery pattern by shifting the differentiative demands placed on the stem cells. The final proportions of animals (one-half regenerated with, and one-half without, the extract) surviving after 60 days were not significantly different.« less

Regenerative toxicology: the role of stem cells in the development of chronic toxicities.

PubMed

Canovas-Jorda, David; Louisse, Jochem; Pistollato, Francesca; Zagoura, Dimitra; Bremer, Susanne

2014-01-01

Human stem cell lines and their derivatives, as alternatives to the use of animal cells or cancer cell lines, have been widely discussed as cellular models in predictive toxicology. However, the role of stem cells in the development of long-term toxicities and carcinogenesis has not received great attention so far, despite growing evidence indicating the relationship of stem cell damage to adverse effects later in life. However, testing this in vitro is a scientific/technical challenge in particular due to the complex interplay of factors existing under physiological conditions. Current major research programs in stem cell toxicity are not aiming to demonstrate that stem cells can be targeted by toxicants. Therefore, this knowledge gap needs to be addressed in additional research activities developing technical solutions and defining appropriate experimental designs. The current review describes selected examples of the role of stem cells in the development of long-term toxicities in the brain, heart or liver and in the development of cancer. The presented examples illustrate the need to analyze the contribution of stem cells to chronic toxicity in order to make a final conclusion whether stem cell toxicities are an underestimated risk in mechanism-based safety assessments. This requires the development of predictive in vitro models allowing the assessment of adverse effects to stem cells on chronic toxicity and carcinogenicity.

[Stem cells in adults].

PubMed

Borge, O J; Funderud, S

2001-08-30

We present a literature review of the plasticity observed by adult stem cells. We have reviewed the literature regarding stem cells from adults in order to summarise their ability to generate cells of other types than those of the tissue/organ from which they were isolated. Adult stem cells have recently been demonstrated to terminally differentiate into cells of other tissues than those from which they were originally isolated. For example, bone marrow cells have been shown to generate liver, nerve, heart and skeletal muscle cells in addition to their well-known ability to produce blood and mesenchymal cells. Most studies demonstrate a proof-of-principle in animal models; much more research is needed before adult stem cells can be utilised in human medicine. However, the published reports are encouraging and give reasons for a cautious optimism with regard to future clinical use.

Mechanisms of cellular therapy in respiratory diseases.

PubMed

Abreu, Soraia C; Antunes, Mariana A; Pelosi, Paolo; Morales, Marcelo M; Rocco, Patricia R M

2011-09-01

Stem cells present a variety of clinical implications in the lungs. According to their origin, these cells can be divided into embryonic and adult stem cells; however, due to the important ethical and safety limitations that are involved in the embryonic stem cell use, most studies have chosen to focus on adult stem cell therapy. This article aims to present and clarify the recent advances in the field of stem cell biology, as well as to highlight the effects of mesenchymal stem cell (MSC) therapy in the context of acute lung injury/acute respiratory distress syndrome and chronic disorders such as lung fibrosis and chronic obstructive pulmonary disease. For this purpose, we performed a critical review of adult stem cell therapies, covering the main clinical and experimental studies published in Pubmed databases in the past 11 years. Different characteristics were extracted from these articles, such as: the experimental model, strain, cellular type and administration route used as well as the positive or negative effects obtained. There is evidence for beneficial effects of MSC on lung development, repair, and remodeling. The engraftment in the injured lung does not occur easily, but several studies report that paracrine factors can be effective in reducing inflammation and promoting tissue repair. MSC releases several growth factors and anti-inflammatory cytokines that regulate endothelial and epithelial permeability and reduce the severity of inflammation. A better understanding of the mechanisms that control cell division and differentiation, as well as of their paracrine effects, is required to enable the optimal use of bone marrow-derived stem cell therapy to treat human respiratory diseases.

New Monoclonal Antibodies to Defined Cell Surface Proteins on Human Pluripotent Stem Cells.

PubMed

O'Brien, Carmel M; Chy, Hun S; Zhou, Qi; Blumenfeld, Shiri; Lambshead, Jack W; Liu, Xiaodong; Kie, Joshua; Capaldo, Bianca D; Chung, Tung-Liang; Adams, Timothy E; Phan, Tram; Bentley, John D; McKinstry, William J; Oliva, Karen; McMurrick, Paul J; Wang, Yu-Chieh; Rossello, Fernando J; Lindeman, Geoffrey J; Chen, Di; Jarde, Thierry; Clark, Amander T; Abud, Helen E; Visvader, Jane E; Nefzger, Christian M; Polo, Jose M; Loring, Jeanne F; Laslett, Andrew L

2017-03-01

The study and application of human pluripotent stem cells (hPSCs) will be enhanced by the availability of well-characterized monoclonal antibodies (mAbs) detecting cell-surface epitopes. Here, we report generation of seven new mAbs that detect cell surface proteins present on live and fixed human ES cells (hESCs) and human iPS cells (hiPSCs), confirming our previous prediction that these proteins were present on the cell surface of hPSCs. The mAbs all show a high correlation with POU5F1 (OCT4) expression and other hPSC surface markers (TRA-160 and SSEA-4) in hPSC cultures and detect rare OCT4 positive cells in differentiated cell cultures. These mAbs are immunoreactive to cell surface protein epitopes on both primed and naive state hPSCs, providing useful research tools to investigate the cellular mechanisms underlying human pluripotency and states of cellular reprogramming. In addition, we report that subsets of the seven new mAbs are also immunoreactive to human bone marrow-derived mesenchymal stem cells (MSCs), normal human breast subsets and both normal and tumorigenic colorectal cell populations. The mAbs reported here should accelerate the investigation of the nature of pluripotency, and enable development of robust cell separation and tracing technologies to enrich or deplete for hPSCs and other human stem and somatic cell types. Stem Cells 2017;35:626-640. © 2016 The Authors Stem Cells published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

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

PubMed

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

2015-05-01

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

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

NASA Astrophysics Data System (ADS)

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

2017-04-01

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

In search of adult renal stem cells.

PubMed

Anglani, F; Forino, M; Del Prete, D; Tosetto, E; Torregrossa, R; D'Angelo, A

2004-01-01

The therapeutic potential of adult stem cells in the treatment of chronic degenerative diseases has becoming increasingly evident over the last few years. Significant attention is currently being paid to the development of novel treatments for acute and chronic kidney diseases too. To date, promising sources of stem cells for renal therapies include adult bone marrow stem cells and the kidney precursors present in the early embryo. Both cells have clearly demonstrated their ability to differentiate into the kidney's specialized structures. Adult renal stem cells have yet to be identified, but the papilla is where the stem cell niche is probably located. Now we need to isolate and characterize the fraction of papillary cells that constitute the putative renal stem cells. Our growing understanding of the cellular and molecular mechanisms behind kidney regeneration and repair processes - together with a knowledge of the embryonic origin of renal cells - should induce us, however, to bear in mind that in the kidney, as in other mesenchymal tissues, the need for a real stem cell compartment might be less important than the phenotypic flexibility of tubular cells. Thus, by displaying their plasticity during kidney maintenance and repair, terminally differentiated cells may well function as multipotent stem cells despite being at a later stage of maturation than adult stem cells. One of the major tasks of Regenerative Medicine will be to disclose the molecular mechanisms underlying renal tubular plasticity and to exploit its biological and therapeutic potential.

Adult Lung Spheroid Cells Contain Progenitor Cells and Mediate Regeneration in Rodents With Bleomycin-Induced Pulmonary Fibrosis.

PubMed

Henry, Eric; Cores, Jhon; Hensley, M Taylor; Anthony, Shirena; Vandergriff, Adam; de Andrade, James B M; Allen, Tyler; Caranasos, Thomas G; Lobo, Leonard J; Cheng, Ke

2015-11-01

Lung diseases are devastating conditions and ranked as one of the top five causes of mortality worldwide according to the World Health Organization. Stem cell therapy is a promising strategy for lung regeneration. Previous animal and clinical studies have focused on the use of mesenchymal stem cells (from other parts of the body) for lung regenerative therapies. We report a rapid and robust method to generate therapeutic resident lung progenitors from adult lung tissues. Outgrowth cells from healthy lung tissue explants are self-aggregated into three-dimensional lung spheroids in a suspension culture. Without antigenic sorting, the lung spheroids recapitulate the stem cell niche and contain a natural mixture of lung stem cells and supporting cells. In vitro, lung spheroid cells can be expanded to a large quantity and can form alveoli-like structures and acquire mature lung epithelial phenotypes. In severe combined immunodeficiency mice with bleomycin-induced pulmonary fibrosis, intravenous injection of human lung spheroid cells inhibited apoptosis, fibrosis, and infiltration but promoted angiogenesis. In a syngeneic rat model of pulmonary fibrosis, lung spheroid cells outperformed adipose-derived mesenchymal stem cells in reducing fibrotic thickening and infiltration. Previously, lung spheroid cells (the spheroid model) had only been used to study lung cancer cells. Our data suggest that lung spheroids and lung spheroid cells from healthy lung tissues are excellent sources of regenerative lung cells for therapeutic lung regeneration. The results from the present study will lead to future human clinical trials using lung stem cell therapies to treat various incurable lung diseases, including pulmonary fibrosis. The data presented here also provide fundamental knowledge regarding how injected stem cells mediate lung repair in pulmonary fibrosis. ©AlphaMed Press.

Presentation, diagnosis and management of limbal stem cell deficiency.

PubMed

Sejpal, Kunjal; Bakhtiari, Pejman; Deng, Sophie X

2013-01-01

The human corneal surface epithelium is continuously repopulated by the limbal stem cells (LSCs). Limbal Stem Cell Deficiency (LSCD) can lead to corneal opacity and vascularization, with consequent visual impairment or blindness. Many acquired and congenital diseases can lead to LCSD by direct injury to the LSCs, destruction of LSC niche, or both. Based on the severity of the disease, LSCD can present with various symptoms and signs. Although LSCD can be detected clinically, laboratory tests are necessary to confirm the diagnosis and monitor the disease progression. This article concisely reviews the clinical presentation, techniques for diagnosis and management of LSCD.

SCF increases in utero-labeled stem cells migration and improves wound healing.

PubMed

Zgheib, Carlos; Xu, Junwang; Mallette, Andrew C; Caskey, Robert C; Zhang, Liping; Hu, Junyi; Liechty, Kenneth W

2015-01-01

Diabetic skin wounds lack the ability to heal properly and constitute a major and significant complication of diabetes. Nontraumatic lower extremity amputations are the number one complication of diabetic skin wounds. The complexity of their pathophysiology requires an intervention at many levels to enhance healing and wound closure. Stem cells are a promising treatment for diabetic skin wounds as they have the ability to correct abnormal healing. Stem cell factor (SCF), a chemokine expressed in the skin, can induce stem cells migration, however the role of SCF in diabetic skin wound healing is still unknown. We hypothesize that SCF would correct the impairment and promote the healing of diabetic skin wounds. Our results show that SCF improved wound closure in diabetic mice and increased HIF-1α and vascular endothelial growth factor (VEGF) expression levels in these wounds. SCF treatment also enhanced the migration of red fluorescent protein (RFP)-labeled skin stem cells via in utero intra-amniotic injection of lenti-RFP at E8. Interestingly these RFP+ cells are present in the epidermis, stain negative for K15, and appear to be distinct from the already known hair follicle stem cells. These results demonstrate that SCF improves diabetic wound healing in part by increasing the recruitment of a unique stem cell population present in the skin. © 2015 by the Wound Healing Society.

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

PubMed

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

2013-01-01

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

Differential Properties of Human ALP+ Periodontal Ligament Stem Cells vs Their ALP- Counterparts

PubMed Central

Tran, Quynh T; El-Ayachi, Ikbale; Bhatti, Fazal-Ur-Rehman; Bahabri, Rayan; Al-Habib, Mey; Huang, George TJ

2015-01-01

Characterizing subpopulations of stem cells is important to understand stem cell properties. Tissue-nonspecific alkaline phosphatase (ALP) is associated with mineral tissue forming cells as well as stem cells. Information regarding ALP subpopulation of human periodontal ligament stem cells (hPDLSCs) is limited. In the present study, we examined ALP+ and ALP− hPDLSC subpopulations, their surface markers STRO-1 and CD146, and the expression of stemness genes at various cell passages. We found that ALP+ subpopulation had higher levels of STRO-1 (30.6 ± 5.6%) and CD146 (90.4 ± 3.3%) compared to ALP− (STRO-1: 0.5 ± 0.1%; CD146: 75.3 ± 7.2%). ALP+ cells expressed significantly higher levels of stemness associated genes, NANOG, OCT4 and SOX than ALP− cells at low cell passages of 2-3 (p<0.05). ALP+ and ALP− cells had similar osteogenic, chondrogenic and neurogenic potential while ALP−, not ALP+ cells, lacked adipogenic potential. Upon continuous culturing and passaging, ALP+ continued to express higher stemness genes and STRO-1 and CD146 than ALP− cells at ≥passage 19. Under conditions (over-confluence and vitamin C treatment) when ALP+ subpopulation was increased, the stemness gene levels of ALP+ was no longer significantly higher than those in ALP− cells. In conclusion, ALP+ hPDLSCs possess differential properties from their ALP− counterparts. PMID:26807329

FDA regulation of adult stem cell therapies as used in sports medicine.

PubMed

Chirba, Mary Ann; Sweetapple, Berkley; Hannon, Charles P; Anderson, John A

2015-02-01

In sports medicine, adult stem cells are the subject of great interest. Several uses of stem cells are under investigation including cartilage repair, meniscal regeneration, anterior cruciate ligament reconstruction, and tendinopathy. Extensive clinical and basic science research is warranted as stem cell therapies become increasingly common in clinical practice. In the United States, the Food and Drug Administration (FDA) is responsible for regulating the use of stem cells through its "Human Cells, Tissues, and Cellular and Tissue-Based Products" regulations. This report provides a brief overview of FDA regulation of adult stem cells. Several common clinical case scenarios are then presented that highlight how stem cells are currently being used in sports medicine and how current FDA regulations are likely to affect the physicians who use them. In the process, it explains how a variety of factors in sourcing and handling these cells, particularly the extent of cell manipulation, will affect what a physician can and cannot do without first obtaining the FDA's express approval. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

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

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

PubMed

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

2017-01-01

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

Ethical considerations when counseling patients about stem cell tourism.

PubMed

Tsou, Amy

2015-02-01

Worldwide, many clinics market stem-cell based interventions often touted as effective for many diseases including spinal cord injury, multiple sclerosis (MS), and other neurodegenerative diseases. These clinics and their expensive, unproven treatments continue to fuel the practice of stem cell tourism. Given concerns about patient exploitation and safety, how should the physician engage a patient who wants to pursue such treatments? This article presents the case of a patient with neuromyelitis optica interested in pursuing expensive stem cell injections abroad. This article describes stem cell tourism along with some of the ethical issues physicians should consider, while also providing practical resources that physicians may employ to educate and engage patients in making an informed decision.

Intra-femoral injection of human mesenchymal stem cells.

PubMed

Mohanty, Sindhu T; Bellantuono, Ilaria

2013-01-01

In vivo transplantation of putative populations of hematopoietic stem cells (HSC) and assessment of their engraftment is considered the golden standard to assess their quality and degree of stemness. Transplantation is usually carried out by intravenous injection in murine models and assessment of engraftment is performed by monitoring the number and type of mature blood cells produced by the donor cells in time. In contrast intravenous injection of mesenchymal stem cells (MSC), the multipotent stem cells present in bone marrow and capable of differentiating to osteoblasts, chondrocytes and adipocytes, has not been successful. This is due to limited or absent engraftment levels. Here, we describe the use of intra-femoral injection as an improved method to assess MSC engraftment to bone and bone marrow and their quality.

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

PubMed

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

2011-04-01

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

Brain Cancer Stem Cells Display Preferential Sensitivity to Akt Inhibition

PubMed Central

Eyler, Christine E.; Foo, Wen-Chi; LaFiura, Katherine M.; McLendon, Roger E.; Hjelmeland, Anita B.; Rich, Jeremy N.

2009-01-01

Malignant brain tumors are among the most lethal cancers, and conventional therapies are largely limited to palliation. Novel therapies targeted against specific molecular pathways may offer improved efficacy and reduced toxicity compared to conventional therapies, but initial clinical trials of molecular targeted agents in brain cancer therapy have been frequently disappointing. In brain tumors and other cancers, subpopulations of tumor cells have recently been characterized by their ability to self-renew and initiate tumors. Although these cancer stem cells, or tumor initiating cells, are often only present in small numbers in human tumors, mounting evidence suggests that cancer stem cells contribute to tumor maintenance and therapeutic resistance. Thus, the development of therapies that target cancer stem cell signal transduction and biologies may improve brain tumor patient survival. We now demonstrate that populations enriched for cancer stem cells are preferentially sensitive to an inhibitor of Akt, a prominent cell survival and invasion signaling node. Treatment with an Akt inhibitor more potently reduced the numbers of viable brain cancer stem cells relative to matched non-stem cancer cells associated with a preferential induction of apoptosis and a suppression of neurosphere formation. Akt inhibition also reduced the motility and invasiveness of all tumor cells but had a greater impact on cancer stem cell behaviors. Furthermore, inhibition of Akt activity in cancer stem cells increased survival of immunocompromised mice bearing human glioma xenografts in vivo. Together, these results suggest that Akt inhibitors may function as effective anti-cancer stem cell therapies. PMID:18802038

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

Ebselen Preserves Tissue-Engineered Cell Sheets and their Stem Cells in Hypothermic Conditions.

PubMed

Katori, Ryosuke; Hayashi, Ryuhei; Kobayashi, Yuki; Kobayashi, Eiji; Nishida, Kohji

2016-12-14

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.

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

PubMed

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

2015-11-17

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

Professional regulation: a potentially valuable tool in responding to "stem cell tourism".

PubMed

Zarzeczny, Amy; Caulfield, Timothy; Ogbogu, Ubaka; Bell, Peter; Crooks, Valorie A; Kamenova, Kalina; Master, Zubin; Rachul, Christen; Snyder, Jeremy; Toews, Maeghan; Zoeller, Sonja

2014-09-09

The growing international market for unproven stem cell-based interventions advertised on a direct-to-consumer basis over the internet ("stem cell tourism") is a source of concern because of the risks it presents to patients as well as their supporters, domestic health care systems, and the stem cell research field. Emerging responses such as public and health provider-focused education and national regulatory efforts are encouraging, but the market continues to grow. Physicians play a number of roles in the stem cell tourism market and, in many jurisdictions, are members of a regulated profession. In this article, we consider the use of professional regulation to address physician involvement in stem cell tourism. Although it is not without its limitations, professional regulation is a potentially valuable tool that can be employed in response to problematic types of physician involvement in the stem cell tourism market. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Mesenchymal Stem and Progenitor Cells in Normal and Dysplastic Hematopoiesis—Masters of Survival and Clonality?

PubMed Central

Pleyer, Lisa; Valent, Peter; Greil, Richard

2016-01-01

Myelodysplastic syndromes (MDS) are malignant hematopoietic stem cell disorders that have the capacity to progress to acute myeloid leukemia (AML). Accumulating evidence suggests that the altered bone marrow (BM) microenvironment in general, and in particular the components of the stem cell niche, including mesenchymal stem cells (MSCs) and their progeny, play a pivotal role in the evolution and propagation of MDS. We here present an overview of the role of MSCs in the pathogenesis of MDS, with emphasis on cellular interactions in the BM microenvironment and related stem cell niche concepts. MSCs have potent immunomodulatory capacities and communicate with diverse immune cells, but also interact with various other cellular components of the microenvironment as well as with normal and leukemic stem and progenitor cells. Moreover, compared to normal MSCs, MSCs in MDS and AML often exhibit altered gene expression profiles, an aberrant phenotype, and abnormal functional properties. These alterations supposedly contribute to the “reprogramming” of the stem cell niche into a disease-permissive microenvironment where an altered immune system, abnormal stem cell niche interactions, and an impaired growth control lead to disease progression. The current article also reviews molecular targets that play a role in such cellular interactions and possibilities to interfere with abnormal stem cell niche interactions by using specific targeted drugs. PMID:27355944

Development of a Xeno-Free Feeder-Layer System from Human Umbilical Cord Mesenchymal Stem Cells for Prolonged Expansion of Human Induced Pluripotent Stem Cells in Culture

PubMed Central

Zou, Qing; Wu, Mingjun; Zhong, Liwu; Fan, Zhaoxin; Zhang, Bo; Chen, Qiang; Ma, Feng

2016-01-01

Various feeder layers have been extensively applied to support the prolonged growth of human pluripotent stem cells (hPSCs) for in vitro cultures. Among them, mouse embryonic fibroblast (MEF) and mouse fibroblast cell line (SNL) are most commonly used feeder cells for hPSCs culture. However, these feeder layers from animal usually cause immunogenic contaminations, which compromises the potential of hPSCs in clinical applications. In the present study, we tested human umbilical cord mesenchymal stem cells (hUC-MSCs) as a potent xeno-free feeder system for maintaining human induced pluripotent stem cells (hiPSCs). The hUC-MSCs showed characteristics of MSCs in xeno-free culture condition. On the mitomycin-treated hUC-MSCs feeder, hiPSCs maintained the features of undifferentiated human embryonic stem cells (hESCs), such as low efficiency of spontaneous differentiation, stable expression of stemness markers, maintenance of normal karyotypes, in vitro pluripotency and in vivo ability to form teratomas, even after a prolonged culture of more than 30 passages. Our study indicates that the xeno-free culture system may be a good candidate for growth and expansion of hiPSCs as the stepping stone for stem cell research to further develop better and safer stem cells. PMID:26882313

Managing the potential and pitfalls during clinical translation of emerging stem cell therapies

PubMed Central

2014-01-01

We are moving into a new era of stem cell research where many possibilities for treatment of degenerative, chronic and/or fatal diseases and injuries are becoming primed for clinical trial. These reports have led millions of people worldwide to hope that regenerative medicine is about to revolutionise biomedicine: either through transplantation of cells grown in the laboratory, or by finding ways to stimulate a patient’s intrinsic stem cells to repair diseased and damaged organs. While major contributions of stem cells to drug discovery, safety and efficacy testing, as well as modelling ‘diseases in a dish’ are also expected, it is the in vivo use of stem cells that has captured the general public’s attention. However, public misconceptions of stem cell potential and applications can leave patients vulnerable to the influences of profit driven entities selling unproven treatments without solid scientific basis or appropriate clinical testing or follow up. This review provides a brief history of stem cell clinical translation together with an overview of the properties, potential, and current clinical application of various stem cell types. In doing so it presents a clearer picture of the inherent risks and opportunities associated with stem cell research translation, and thus offers a framework to help realise invested expectations more quickly, safely and effectively. PMID:24949190

Mesenchymal Stem and Progenitor Cells in Normal and Dysplastic Hematopoiesis-Masters of Survival and Clonality?

PubMed

Pleyer, Lisa; Valent, Peter; Greil, Richard

2016-06-27

Myelodysplastic syndromes (MDS) are malignant hematopoietic stem cell disorders that have the capacity to progress to acute myeloid leukemia (AML). Accumulating evidence suggests that the altered bone marrow (BM) microenvironment in general, and in particular the components of the stem cell niche, including mesenchymal stem cells (MSCs) and their progeny, play a pivotal role in the evolution and propagation of MDS. We here present an overview of the role of MSCs in the pathogenesis of MDS, with emphasis on cellular interactions in the BM microenvironment and related stem cell niche concepts. MSCs have potent immunomodulatory capacities and communicate with diverse immune cells, but also interact with various other cellular components of the microenvironment as well as with normal and leukemic stem and progenitor cells. Moreover, compared to normal MSCs, MSCs in MDS and AML often exhibit altered gene expression profiles, an aberrant phenotype, and abnormal functional properties. These alterations supposedly contribute to the "reprogramming" of the stem cell niche into a disease-permissive microenvironment where an altered immune system, abnormal stem cell niche interactions, and an impaired growth control lead to disease progression. The current article also reviews molecular targets that play a role in such cellular interactions and possibilities to interfere with abnormal stem cell niche interactions by using specific targeted drugs.

Development of a Xeno-Free Feeder-Layer System from Human Umbilical Cord Mesenchymal Stem Cells for Prolonged Expansion of Human Induced Pluripotent Stem Cells in Culture.

PubMed

Zou, Qing; Wu, Mingjun; Zhong, Liwu; Fan, Zhaoxin; Zhang, Bo; Chen, Qiang; Ma, Feng

2016-01-01

Various feeder layers have been extensively applied to support the prolonged growth of human pluripotent stem cells (hPSCs) for in vitro cultures. Among them, mouse embryonic fibroblast (MEF) and mouse fibroblast cell line (SNL) are most commonly used feeder cells for hPSCs culture. However, these feeder layers from animal usually cause immunogenic contaminations, which compromises the potential of hPSCs in clinical applications. In the present study, we tested human umbilical cord mesenchymal stem cells (hUC-MSCs) as a potent xeno-free feeder system for maintaining human induced pluripotent stem cells (hiPSCs). The hUC-MSCs showed characteristics of MSCs in xeno-free culture condition. On the mitomycin-treated hUC-MSCs feeder, hiPSCs maintained the features of undifferentiated human embryonic stem cells (hESCs), such as low efficiency of spontaneous differentiation, stable expression of stemness markers, maintenance of normal karyotypes, in vitro pluripotency and in vivo ability to form teratomas, even after a prolonged culture of more than 30 passages. Our study indicates that the xeno-free culture system may be a good candidate for growth and expansion of hiPSCs as the stepping stone for stem cell research to further develop better and safer stem cells.

BDNF improves the efficacy ERG amplitude maintenance by transplantation of retinal stem cells in RCS rats.

PubMed

Tian, Chunyu; Weng, Chuan Chuang; Yin, Zheng Qin

2010-01-01

The aim of this study was to evaluate the efficacy of subretinal transplantation of rat retinal stem cell when combined with Brain-derived neurotrophic factor (BDNF) in a rat model of retinal degeneration - Royal College of Surgeons (RCS) rats. Retinal stem cells were derived from embryonic day 17 Long-Evans rats and pre-labeled with fluorescence pigment-DiI prior to transplant procedures. RCS rats received injections of retinal stem cells, stem cells+BDNF, phosphate buffered saline or BNDF alone (n = 3 eyes for each procedure). At 1, 2 and 3 months after transplantation, the electroretinogram (ERG) was assessed and the outer nuclear layer thickness measured. The eyes receiving retinal stem cell and stem cell+BDNF transplants showed better photoreceptor maintenance than the other groups (P < 0.01) at all time points. One month after retina transplantation, the amplitudes of rod-ERG and Max-ERG b waves were significantly higher the eyes with stem cells+BDNF (P < 0.01), however, this difference was not seen at two and three months post transplantation. BDNF treatment alone group (without transplanted cells) had no effect when compared to buffer injections. The present results indicate that BDNF can enhance the short-term efficacy of the retinal stem cell transplantation in treating retinal degenerative disease.

Ethical clinical translation of stem cell interventions for neurologic disease.

PubMed

Cote, David J; Bredenoord, Annelien L; Smith, Timothy R; Ammirati, Mario; Brennum, Jannick; Mendez, Ivar; Ammar, Ahmed S; Balak, Naci; Bolles, Gene; Esene, Ignatius Ngene; Mathiesen, Tiit; Broekman, Marike L

2017-01-17

The application of stem cell transplants in clinical practice has increased in frequency in recent years. Many of the stem cell transplants in neurologic diseases, including stroke, Parkinson disease, spinal cord injury, and demyelinating diseases, are unproven-they have not been tested in prospective, controlled clinical trials and have not become accepted therapies. Stem cell transplant procedures currently being carried out have therapeutic aims, but are frequently experimental and unregulated, and could potentially put patients at risk. In some cases, patients undergoing such operations are not included in a clinical trial, and do not provide genuinely informed consent. For these reasons and others, some current stem cell interventions for neurologic diseases are ethically dubious and could jeopardize progress in the field. We provide discussion points for the evaluation of new stem cell interventions for neurologic disease, based primarily on the new Guidelines for Stem Cell Research and Clinical Translation released by the International Society for Stem Cell Research in May 2016. Important considerations in the ethical translation of stem cells to clinical practice include regulatory oversight, conflicts of interest, data sharing, the nature of investigation (e.g., within vs outside of a clinical trial), informed consent, risk-benefit ratios, the therapeutic misconception, and patient vulnerability. To help guide the translation of stem cells from the laboratory into the neurosurgical clinic in an ethically sound manner, we present an ethical discussion of these major issues at stake in the field of stem cell clinical research for neurologic disease. © 2016 American Academy of Neurology.

A Synthetic Triterpenoid CDDO-Im Inhibits Tumorsphere Formation by Regulating Stem Cell Signaling Pathways in Triple-Negative Breast Cancer

PubMed Central

Wahler, Joseph; Liby, Karen T.; Sporn, Michael B.; Suh, Nanjoo

2014-01-01

Triple-negative breast cancer is associated with poor prognosis because of a high rate of tumor recurrence and metastasis. Previous studies demonstrated that the synthetic triterpenoid, CDDO-Imidazolide (CDDO-Im) induced cell cycle arrest and apoptosis in triple-negative breast cancer. Since a small subpopulation of cancer stem cells has been suggested to be responsible for drug resistance and metastasis of tumors, our present study determined whether the effects of CDDO-Im in triple-negative breast cancer are due to the inhibition of a cancer stem cell subpopulation. CDDO-Im treatment markedly induced cell cycle arrest at G2/M-phase and apoptosis in the triple-negative breast cancer cell lines, SUM159 and MDA-MB-231. Because SUM159 cells were more sensitive to CDDO-Im than MDA-MB-231 cells, the effects of CDDO-Im on the cancer stem cell subpopulation were further investigated in SUM159 cells. SUM159 cells formed tumorspheres in culture, and the cancer stem cell subpopulation, CD24−/EpCAM+ cells, was markedly enriched in SUM159 tumorspheres. The CD24−/EpCAM+ cells in SUM159 tumorspheres were significantly inhibited by CDDO-Im treatment. CDDO-Im also significantly decreased sphere forming efficiency and tumorsphere size in both primary and secondary sphere cultures. PCR array of stem cell signaling genes showed that expression levels of many key molecules in the stem cell signaling pathways, such as Notch, TGF-β/Smad, Hedgehog and Wnt, were significantly down-regulated by CDDO-Im in SUM159 tumorspheres. Protein levels of Notch receptors (c-Notch1, Notch1 and Notch3), TGF-β/Smad (pSmad2/3) and Hedgehog downstream effectors (GLI1) also were markedly reduced by CDDO-Im. In conclusion, the present study demonstrates that the synthetic triterpenoid, CDDO-Im, is a potent anti-cancer agent against triple-negative breast cancer cells by targeting the cancer stem cell subpopulation. PMID:25229616

Transplantation of Reprogrammed Autologous Stem Cells for Chronic Pain and Drug Abuse

DTIC Science & Technology

2016-07-01

from mesenchymal stem cells (MSCs) and to investigate the analgesic and anti- tolerance effects and the safety of CLCs in animal models. We have...had significant analgesic and robust anti-tolerance effects in both cellular and animal models. Our research has led to 5 poster presentations at...reprogramming, Pain management, Tolerance, Drug abuse, Cell cultures, Spinal transplantation of autologous stem cells, Animal behavioral tests 16. SECURITY

[A European discussion about stem cells for therapeutic use].

PubMed

Boer, G J

2002-06-29

Stem cells as a source material for growing cellular transplants to repair dysfunctional organs appear to be a new challenge for medical science. Though stem cells are also present in foetal and adult organs, embryonic stem cells from the pre-implantation embryo in particular have the potency to proliferate easily in vitro and the capacity to differentiate into all the body's organ-specific cells. Therefore, these are the ideal cells for developing new cell transplantation therapies for diseases such as Parkinson's disease, diabetes mellitus and heart failure. The use of spare in vitro fertilization (IVF) embryos or pre-implantation embryos specially created to harvest human embryonic stem cells is, however, controversial and an ethical problem. In a European discussion platform organised by the European Commission Research Directorate-General, the status quo of the progress was presented and subsequently commented upon and discussed in terms of medical-ethical, social, industrial and patient interests. The expectations of this new medical technology were high, but clinical trials seem only acceptable once the in vitro differentiation of stem cells can be adequately controlled and once it is known how in vitro prepared stem cells behave after implantation. The ethical justification of the use of in vitro pre-implantation embryos remains controversial. The prevailing view is that the interests of severely ill patients for whom no adequate therapy exists, surmounts the interest of protection of a human in vitro pre-implantation embryo, regardless of whether it was the result of IVF or of transplantation of a somatic cell nucleus of the patient in an enucleated donor egg cell (therapeutic cloning).

A block in lineage differentiation of immortal human mammary stem / progenitor cells by ectopically-expressed oncogenes

PubMed Central

Zhao, Xiangshan; Malhotra, Gautam K.; Band, Hamid; Band, Vimla

2011-01-01

Introduction: Emerging evidence suggests a direct role of cancer stem cells (CSCs) in the development of breast cancer. In vitro cellular models that recapitulate properties of CSCs are therefore highly desirable. We have previously shown that normal human mammary epithelial cells (hMECs) immortalized with human telomerase reverse transcriptase (hTERT) possess properties of mammary stem / progenitor cells. Materials and Methods: In the present study, we used this cell system to test the idea that other known hMEC-immortalizing oncogenes (RhoA, HPVE6, HPVE7, p53 mutant, and treatment with γ-radiation), share with hTERT, the ability to maintain mammary stem / progenitor cells. Results: The results presented here demonstrate that similar to hMECs immortalized with hTERT, all hMEC cell lines immortalized using various oncogenic strategies express stem / progenitor cell markers. Furthermore, analyses using 2D and 3D culture assays demonstrate that all the immortal cell lines retain their ability to self-renew and to differentiate along the luminal lineage. Remarkably, the stem / progenitor cell lines generated using various oncogenic strategies exhibit a block in differentiation along the myoepithelial lineage, a trait that is retained on hTERT-immortalized stem / progenitors. The inability to differentiate along the myoepithelial lineage could be induced by ectopic mutant p53 expression in hTERT-immortalized hMEC. Conclusions: Our studies demonstrate that stem / progenitor cell characteristics of hMECs are maintained upon immortalization by using various cancer-relevant oncogenic strategies. Oncogene-immortalized hMECs show a block in their ability to differentiate along the myoepithelial lineage. Abrogation of the myoepithelial differentiation potential by a number of distinct oncogenic insults suggests a potential explanation for the predominance of luminal and rarity of myoepithelial breast cancers. PMID:22279424

A block in lineage differentiation of immortal human mammary stem / progenitor cells by ectopically-expressed oncogenes.

PubMed

Zhao, Xiangshan; Malhotra, Gautam K; Band, Hamid; Band, Vimla

2011-01-01

Emerging evidence suggests a direct role of cancer stem cells (CSCs) in the development of breast cancer. In vitro cellular models that recapitulate properties of CSCs are therefore highly desirable. We have previously shown that normal human mammary epithelial cells (hMECs) immortalized with human telomerase reverse transcriptase (hTERT) possess properties of mammary stem / progenitor cells. In the present study, we used this cell system to test the idea that other known hMEC-immortalizing oncogenes (RhoA, HPVE6, HPVE7, p53 mutant, and treatment with γ-radiation), share with hTERT, the ability to maintain mammary stem / progenitor cells. The results presented here demonstrate that similar to hMECs immortalized with hTERT, all hMEC cell lines immortalized using various oncogenic strategies express stem / progenitor cell markers. Furthermore, analyses using 2D and 3D culture assays demonstrate that all the immortal cell lines retain their ability to self-renew and to differentiate along the luminal lineage. Remarkably, the stem / progenitor cell lines generated using various oncogenic strategies exhibit a block in differentiation along the myoepithelial lineage, a trait that is retained on hTERT-immortalized stem / progenitors. The inability to differentiate along the myoepithelial lineage could be induced by ectopic mutant p53 expression in hTERT-immortalized hMEC. Our studies demonstrate that stem / progenitor cell characteristics of hMECs are maintained upon immortalization by using various cancer-relevant oncogenic strategies. Oncogene-immortalized hMECs show a block in their ability to differentiate along the myoepithelial lineage. Abrogation of the myoepithelial differentiation potential by a number of distinct oncogenic insults suggests a potential explanation for the predominance of luminal and rarity of myoepithelial breast cancers.

Evaluating Cell Processes, Quality, and Biomarkers in Pluripotent Stem Cells Using Video Bioinformatics

PubMed Central

Lin, Sabrina C.; Bays, Brett C.; Omaiye, Esther; Bhanu, Bir; Talbot, Prue

2016-01-01

There is a foundational need for quality control tools in stem cell laboratories engaged in basic research, regenerative therapies, and toxicological studies. These tools require automated methods for evaluating cell processes and quality during in vitro passaging, expansion, maintenance, and differentiation. In this paper, an unbiased, automated high-content profiling toolkit, StemCellQC, is presented that non-invasively extracts information on cell quality and cellular processes from time-lapse phase-contrast videos. Twenty four (24) morphological and dynamic features were analyzed in healthy, unhealthy, and dying human embryonic stem cell (hESC) colonies to identify those features that were affected in each group. Multiple features differed in the healthy versus unhealthy/dying groups, and these features were linked to growth, motility, and death. Biomarkers were discovered that predicted cell processes before they were detectable by manual observation. StemCellQC distinguished healthy and unhealthy/dying hESC colonies with 96% accuracy by non-invasively measuring and tracking dynamic and morphological features over 48 hours. Changes in cellular processes can be monitored by StemCellQC and predictions can be made about the quality of pluripotent stem cell colonies. This toolkit reduced the time and resources required to track multiple pluripotent stem cell colonies and eliminated handling errors and false classifications due to human bias. StemCellQC provided both user-specified and classifier-determined analysis in cases where the affected features are not intuitive or anticipated. Video analysis algorithms allowed assessment of biological phenomena using automatic detection analysis, which can aid facilities where maintaining stem cell quality and/or monitoring changes in cellular processes are essential. In the future StemCellQC can be expanded to include other features, cell types, treatments, and differentiating cells. PMID:26848582

Evaluating Cell Processes, Quality, and Biomarkers in Pluripotent Stem Cells Using Video Bioinformatics.

PubMed

Zahedi, Atena; On, Vincent; Lin, Sabrina C; Bays, Brett C; Omaiye, Esther; Bhanu, Bir; Talbot, Prue

2016-01-01

There is a foundational need for quality control tools in stem cell laboratories engaged in basic research, regenerative therapies, and toxicological studies. These tools require automated methods for evaluating cell processes and quality during in vitro passaging, expansion, maintenance, and differentiation. In this paper, an unbiased, automated high-content profiling toolkit, StemCellQC, is presented that non-invasively extracts information on cell quality and cellular processes from time-lapse phase-contrast videos. Twenty four (24) morphological and dynamic features were analyzed in healthy, unhealthy, and dying human embryonic stem cell (hESC) colonies to identify those features that were affected in each group. Multiple features differed in the healthy versus unhealthy/dying groups, and these features were linked to growth, motility, and death. Biomarkers were discovered that predicted cell processes before they were detectable by manual observation. StemCellQC distinguished healthy and unhealthy/dying hESC colonies with 96% accuracy by non-invasively measuring and tracking dynamic and morphological features over 48 hours. Changes in cellular processes can be monitored by StemCellQC and predictions can be made about the quality of pluripotent stem cell colonies. This toolkit reduced the time and resources required to track multiple pluripotent stem cell colonies and eliminated handling errors and false classifications due to human bias. StemCellQC provided both user-specified and classifier-determined analysis in cases where the affected features are not intuitive or anticipated. Video analysis algorithms allowed assessment of biological phenomena using automatic detection analysis, which can aid facilities where maintaining stem cell quality and/or monitoring changes in cellular processes are essential. In the future StemCellQC can be expanded to include other features, cell types, treatments, and differentiating cells.

Odontogenic epithelial stem cells: hidden sources.

PubMed

Padma Priya, Sivan; Higuchi, Akon; Abu Fanas, Salem; Pooi Ling, Mok; Kumari Neela, Vasantha; Sunil, P M; Saraswathi, T R; Murugan, Kadarkarai; Alarfaj, Abdullah A; Munusamy, Murugan A; Kumar, Suresh

2015-12-01

The ultimate goal of dental stem cell research is to construct a bioengineered tooth. Tooth formation occurs based on the well-organized reciprocal interaction of epithelial and mesenchymal cells. The dental mesenchymal stem cells are the best explored, but because the human odontogenic epithelium is lost after the completion of enamel formation, studies on these cells are scarce. The successful creation of a bioengineered tooth is achievable only when the odontogenic epithelium is reconstructed to produce a replica of natural enamel. This article discusses the untapped sources of odontogenic epithelial stem cells in humans, such as those present in the active dental lamina in postnatal life, in remnants of dental lamina (the gubernaculum cord), in the epithelial cell rests of Malassez, and in reduced enamel epithelium. The possible uses of these stem cells in regenerative medicine, not just for enamel formation, are discussed.

The Decay of Stem Cell Nourishment at the Niche

PubMed Central

de Mora, Jaime Font

2013-01-01

Abstract One of the main features of human aging is the loss of adult stem cell homeostasis. Organs that are very dependent on adult stem cells show increased susceptibility to aging, particularly organs that present a vascular stem cell niche. Reduced regenerative capacity in tissues correlates with reduced stem cell function, which parallels a loss of microvascular density (rarefraction) and plasticity. Moreover, the age-related loss of microvascular plasticity and rarefaction has significance beyond metabolic support for tissues because stem cell niches are regulated co-ordinately with the vascular cells. In addition, microvascular rarefaction is related to increased inflammatory signals that may negatively regulate the stem cell population. Thus, the processes of microvascular rarefaction, adult stem cell dysfunction, and inflammation underlie the cycle of physiological decline that we call aging. Observations from new mouse models and humans are discussed here to support the vascular aging theory. We develop a novel theory to explain the complexity of aging in mammals and perhaps in other organisms. The connection between vascular endothelial tissue and organismal aging provides a potential evolutionary conserved mechanism that is an ideal target for the development of therapies to prevent or delay age-related processes in humans. PMID:23937078

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

PubMed Central

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

2015-01-01

The skin is the largest organ of the body and has an array of functions. Skin compartments, epidermis, and hair follicles house stem cells that are indispensable for skin homeostasis and regeneration. These stem cells also contribute to wound repair, resulting in restoration of tissue integrity and function of damaged tissue. Unsuccessful wound healing processes often lead to non-healing wounds. Chronic wounds are caused by depletion of stem cells and a variety of other cellular and molecular mechanisms, many of which are still poorly understood. Current chronic wound therapies are limited, so the search to develop better therapeutic strategies is ongoing. Adult stem cells are gaining recognition as potential candidates for numerous skin pathologies. In this review, we will discuss epidermal and other stem cells present in the skin, and highlight some of the therapeutic applications of epidermal stem cells and other adult stem cells as tools for cell/scaffold-based therapies for non-healing wounds and other skin disorders. We will also discuss emerging concepts and offer some perspectives on how skin tissue-engineered products can be optimized to provide efficacious therapy in cutaneous repair and regeneration. PMID:26512657

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

PubMed

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

2015-10-23

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

Efficient Purification and Optimization of Wnt3a, a Novel Therapeutic for Tissue Regeneration

NASA Astrophysics Data System (ADS)

Madhav, D.; Helms, J.; Dhamdhere, G.

2012-12-01

Wnt is a secreted protein that is present naturally in the body. When an organism is injured the amount of Wnt in the affected area increases. This protein acts as an activator of adult stem cells and signals them to begin differentiating and proliferating. This stem cell response augments the ongoing efforts of injured cells to heal faster by becoming the cells that were damaged by the injury. Adult stem cells play a great role in the healing of wounds, but as organisms age the amount of stem cells in their body decreases. This decrease, in effect, slows the healing of injuries because no stem cells are present to help the regenerative efforts of the body. The Wnt protein induces these stem cells not only to differentiate and proliferate, but also to self-replicate. The ability of Wnt to induce adult stem cells to self -replicate gives us an option to use the protein as a potential tissue regenerative drug. Post-translational Wnt has a lipid modification that makes the protein insoluble in water. To overcome this we fuse the protein with a liposome. A liposome is a lipid sphere with an aqueous center and a phospholipid membrane. The Wnt protein does not lose its function when joined with a liposome. Using this knowledge we can develop a viable means to inject the Wnt protein directly into organisms. The big problem now is to make enough purified Wnt to manufacture on a large scale.

Selection of stable reference genes for quantitative rt-PCR comparisons of mouse embryonic and extra-embryonic stem cells.

PubMed

Veazey, Kylee J; Golding, Michael C

2011-01-01

Isolation and culture of both embryonic and tissue specific stem cells provide an enormous opportunity to study the molecular processes driving development. To gain insight into the initial events underpinning mammalian embryogenesis, pluripotent stem cells from each of the three distinct lineages present within the preimplantation blastocyst have been derived. Embryonic (ES), trophectoderm (TS) and extraembryonic endoderm (XEN) stem cells possess the developmental potential of their founding lineages and seemingly utilize distinct epigenetic modalities to program gene expression. However, the basis for these differing cellular identities and epigenetic properties remain poorly defined.Quantitative reverse transcription-polymerase chain reaction (qPCR) is a powerful and efficient means of rapidly comparing patterns of gene expression between different developmental stages and experimental conditions. However, careful, empirical selection of appropriate reference genes is essential to accurately measuring transcriptional differences. Here we report the quantitation and evaluation of fourteen commonly used references genes between ES, TS and XEN stem cells. These included: Actb, B2m, Hsp70, Gapdh, Gusb, H2afz, Hk2, Hprt, Pgk1, Ppia, Rn7sk, Sdha, Tbp and Ywhaz. Utilizing three independent statistical analysis, we identify Pgk1, Sdha and Tbp as the most stable reference genes between each of these stem cell types. Furthermore, we identify Sdha, Tbp and Ywhaz as well as Ywhaz, Pgk1 and Hk2 as the three most stable reference genes through the in vitro differentiation of embryonic and trophectoderm stem cells respectively.Understanding the transcriptional and epigenetic regulatory mechanisms controlling cellular identity within these distinct stem cell types provides essential insight into cellular processes controlling both embryogenesis and stem cell biology. Normalizing quantitative RT-PCR measurements using the geometric mean CT values obtained for the identified mRNAs, offers a reliable method to assess differing patterns of gene expression between the three founding stem cell lineages present within the mammalian preimplantation embryo.

The states "race" with the federal government for stem cell research.

PubMed

Sax, Joanna K

2006-01-01

This article presents an innovative study of the effect of individual states and private institutes in pushing forward stem cell research despite a federal ban on creating new stem cell lines. The author analyzes the impact of state legislation, proposing that states are reacting to federal policy by serving as laboratories for what is traditionally federally funded biomedical research.

Regulation of Hematopoietic Stem Cell Behavior by the Nanostructured Presentation of Extracellular Matrix Components

PubMed Central

Muth, Christine Anna; Steinl, Carolin; Klein, Gerd; Lee-Thedieck, Cornelia

2013-01-01

Hematopoietic stem cells (HSCs) are maintained in stem cell niches, which regulate stem cell fate. Extracellular matrix (ECM) molecules, which are an essential part of these niches, can actively modulate cell functions. However, only little is known on the impact of ECM ligands on HSCs in a biomimetic environment defined on the nanometer-scale level. Here, we show that human hematopoietic stem and progenitor cell (HSPC) adhesion depends on the type of ligand, i.e., the type of ECM molecule, and the lateral, nanometer-scaled distance between the ligands (while the ligand type influenced the dependency on the latter). For small fibronectin (FN)–derived peptide ligands such as RGD and LDV the critical adhesive interligand distance for HSPCs was below 45 nm. FN-derived (FN type III 7–10) and osteopontin-derived protein domains also supported cell adhesion at greater distances. We found that the expression of the ECM protein thrombospondin-2 (THBS2) in HSPCs depends on the presence of the ligand type and its nanostructured presentation. Functionally, THBS2 proved to mediate adhesion of HSPCs. In conclusion, the present study shows that HSPCs are sensitive to the nanostructure of their microenvironment and that they are able to actively modulate their environment by secreting ECM factors. PMID:23405094

Chemical Activation of the Hypoxia-Inducible Factor Reversibly Reduces Tendon Stem Cell Proliferation, Inhibits Their Differentiation, and Maintains Cell Undifferentiation.

PubMed

Menon, Alessandra; Creo, Pasquale; Piccoli, Marco; Bergante, Sonia; Conforti, Erika; Banfi, Giuseppe; Randelli, Pietro; Anastasia, Luigi

2018-01-01

Adult stem cell-based therapeutic approaches for tissue regeneration have been proposed for several years. However, adult stem cells are usually limited in number and difficult to be expanded in vitro, and they usually tend to quickly lose their potency with passages, as they differentiate and become senescent. Culturing stem cells under reduced oxygen tensions (below 21%) has been proposed as a tool to increase cell proliferation, but many studies reported opposite effects. In particular, cell response to hypoxia seems to be very stem cell type specific. Nonetheless, it is clear that a major role in this process is played by the hypoxia inducible factor (HIF), the master regulator of cell response to oxygen deprivation, which affects cell metabolism and differentiation. Herein, we report that a chemical activation of HIF in human tendon stem cells reduces their proliferation and inhibits their differentiation in a reversible and dose-dependent manner. These results support the notion that hypoxia, by activating HIF, plays a crucial role in preserving stem cells in an undifferentiated state in the "hypoxic niches" present in the tissue in which they reside before migrating in more oxygenated areas to heal a damaged tissue.

Stimulatory effect of icariin on the proliferation of neural stem cells from rat hippocampus.

PubMed

Fu, Xiaolong; Li, Shujun; Zhou, Shaoyu; Wu, Qin; Jin, Feng; Shi, Jingshan

2018-01-29

Icariin (ICA), a major ingredient of Epimediumbrevicornum, has various pharmacological activities including central nervous system protective functions such as the improvement of learning and memory function in mice models of Alzheimer's disease. It has been reported that ICA can promote regeneration of peripheral nerve and functional recovery. The purpose of this study was to investigate the potentiating effect of ICA on the proliferation of rat hippocampal neural stem cells, and explore the possible mechanism involved. Primary neural stem cells were prepared from the hippocampus of newly born SD rats, and cells were cultured in special stem cell culture medium. Neural stem cells were confirmed by immunofluorescence detection of nestin, NSE and GFAP expression. The effect of ICA on the growth and proliferation of the neural stem cells was evaluated by 5-ethynyl-2-deoxyuridine (EdU) labeling of proliferating cells, and photomicrographic images of the cultured neural stem cells. Further, the mechanism of ICA-induced cell proliferation of neural stem cells was investigated by analyzing the gene and protein expression of cell cycle related genes cyclin D1 and p21. The present study showed that icariin promotes the growth and proliferation of neural stem cells from rat hippocampus in a dose-dependent manner. Incubation of cells with icariin resulted in significant increase in the number of stem cell spheres as well as the increased incorporation of EdU when compared with cells exposed to control vehicle. In addition, it was found that icariin-induced effect on neural stem cells is associated with increased mRNA and protein expression of cell cycle genes cyclin D1 and p21. This study evidently demonstrates the potentiating effect of ICA on neural stem cell growth and proliferation, which might be mediated through regulation of cell cycle gene and protein expression promoting cell cycle progression.

Innovation in stem cell advocacy: you only get what you can measure.

PubMed

Jakimo, Alan L; Fernandez, Alan C

2011-11-01

We propose that stem cell advocacy must engage in self-analysis to determine how to be maximally effective. For this analysis, eight advocacy elements can be measured: agitation, legislation, regulation, litigation, policy development, collaboration, education and innovation. For several of these elements, we show that stem cell advocates, particularly advocates for human embryonic stem cell research, have been matched by their opponents. This demonstrates the need for combining innovation and collaboration with advocacy-oriented education. To pursue innovative and collaborative education, we propose a 'bench-to-public knowledge' model and present some preliminary observations made with this model for different stem cell types. We also propose development of a semantic web information system to be operated within Internet Cloud/Apps/Social Media. We call this system the 'Stem Cell Information Technology Accelerator Platform'. Toward its construction, we propose formation of a working group to conceive semantic web ontology for stem cell science and its clinical translation into medicine. This ontology would function as a map of the relationships between and among the various informational components comprising discourse on stem cell research and its clinical translation, and would allow various stakeholders to contribute to evolving models of that science and translation. These models could, in turn, support an innovative and collaborative approach to education in furtherance of stem cell advocacy.

Representations of stem cell clinics on Twitter.

PubMed

Kamenova, Kalina; Reshef, Amir; Caulfield, Timothy

2014-12-01

The practice of travelling abroad to receive unproven and unregulated stem cell treatments has become an increasingly problematic global phenomenon known as 'stem cell tourism'. In this paper, we examine representations of nine major clinics and providers of such treatments on the microblogging network Twitter. We collected and conducted a content analysis of Twitter posts (n = 363) by these establishments and by other users mentioning them, focusing specifically on marketing claims about treatment procedures and outcomes, discussions of safety and efficacy of stem cell transplants, and specific representations of patients' experiences. Our analysis has shown that there were explicit claims or suggestions of benefits associated with unproven stem cell treatments in approximately one third of the tweets and that patients' experiences, whenever referenced, were presented as invariably positive and as testimonials about the efficacy of stem cell transplants. Furthermore, the results indicated that the tone of most tweets (60.2 %) was overwhelmingly positive and there were rarely critical discussions about significant health risks associated with unproven stem cell therapies. When placed in the context of past research on the problems associated with the marketing of unproven stem cell therapies, this analysis of representations on Twitter suggests that discussions in social media have also remained largely uncritical of the stem cell tourism phenomenon, with inaccurate representations of risks and benefits for patients.

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

PubMed

Millman, Jeffrey R; Pagliuca, Felicia W

2017-05-01

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

Template DNA-strand co-segregation and asymmetric cell division in skeletal muscle stem cells.

PubMed

Shinin, Vasily; Gayraud-Morel, Barbara; Tajbakhsh, Shahragim

2009-01-01

Stem cells are present in all tissues and organs, and are crucial for normal regulated growth. How the pool size of stem cells and their progeny is regulated to establish the tissue prenatally, then maintain it throughout life, is a key question in biology and medicine. The ability to precisely locate stem and progenitors requires defining lineage progression from stem to differentiated cells, assessing the mode of cell expansion and self-renewal and identifying markers to assess the different cell states within the lineage. We have shown that during lineage progression from a quiescent adult muscle satellite cell to a differentiated myofibre, both symmetric and asymmetric divisions take place. Furthermore, we provide evidence that a sub-population of label retaining satellite cells co-segregate template DNA strands to one daughter cell. These findings provide a means of identifying presumed stem and progenitor cells within the lineage. In addition, asymmetric segregation of template DNA and the cytoplasmic protein Numb provides a landmark to define cell behaviour as self-renewal and differentiation decisions are being executed.

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.

Magnetically levitated mesenchymal stem cell spheroids cultured with a collagen gel maintain phenotype and quiescence

PubMed Central

Lewis, Natasha S; Lewis, Emily EL; Mullin, Margaret; Wheadon, Helen; Dalby, Matthew J; Berry, Catherine C

2017-01-01

Multicellular spheroids are an established system for three-dimensional cell culture. Spheroids are typically generated using hanging drop or non-adherent culture; however, an emerging technique is to use magnetic levitation. Herein, mesenchymal stem cell spheroids were generated using magnetic nanoparticles and subsequently cultured within a type I collagen gel, with a view towards developing a bone marrow niche environment. Cells were loaded with magnetic nanoparticles, and suspended beneath an external magnet, inducing self-assembly of multicellular spheroids. Cells in spheroids were viable and compared to corresponding monolayer controls, maintained stem cell phenotype and were quiescent. Interestingly, core spheroid necrosis was not observed, even with increasing spheroid size, in contrast to other commonly used spheroid systems. This mesenchymal stem cell spheroid culture presents a potential platform for modelling in vitro bone marrow stem cell niches, elucidating interactions between cells, as well as a useful model for drug delivery studies. PMID:28616152

Reactive Oxygen Species and Mitochondrial Homeostasis as Regulators of Stem Cell Fate and Function.

PubMed

Tan, Darren Q; Suda, Toshio

2018-07-10

The precise role and impact of reactive oxygen species (ROS) in stem cells, which are essential for lifelong tissue homeostasis and regeneration, remain of significant interest to the field. The long-term regenerative potential of a stem cell compartment is determined by the delicate balance between quiescence, self-renewal, and differentiation, all of which can be influenced by ROS levels. Recent Advances: The past decade has seen a growing appreciation for the importance of ROS and redox homeostasis in various stem cell compartments, particularly those of hematopoietic, neural, and muscle tissues. In recent years, the importance of proteostasis and mitochondria in relation to stem cell biology and redox homeostasis has garnered considerable interest. Here, we explore the reciprocal relationship between ROS and stem cells, with significant emphasis on mitochondria as a core component of redox homeostasis. We discuss how redox signaling, involving cell-fate determining protein kinases and transcription factors, can control stem cell function and fate. We also address the impact of oxidative stress on stem cells, especially oxidative damage of lipids, proteins, and nucleic acids. We further discuss ROS management in stem cells, and present recent evidence supporting the importance of mitochondrial activity and its modulation (via mitochondrial clearance, biogenesis, dynamics, and distribution [i.e., segregation and transfer]) in stem cell redox homeostasis. Therefore, elucidating the intricate links between mitochondria, cellular metabolism, and redox homeostasis is envisioned to be critical for our understanding of ROS in stem cell biology and its therapeutic relevance in regenerative medicine. Antioxid. Redox Signal. 00, 000-000.

Genetic engineering of mesenchymal stem cells and its application in human disease therapy.

PubMed

Hodgkinson, Conrad P; Gomez, José A; Mirotsou, Maria; Dzau, Victor J

2010-11-01

The use of stem cells for tissue regeneration and repair is advancing both at the bench and bedside. Stem cells isolated from bone marrow are currently being tested for their therapeutic potential in a variety of clinical conditions including cardiovascular injury, kidney failure, cancer, and neurological and bone disorders. Despite the advantages, stem cell therapy is still limited by low survival, engraftment, and homing to damage area as well as inefficiencies in differentiating into fully functional tissues. Genetic engineering of mesenchymal stem cells is being explored as a means to circumvent some of these problems. This review presents the current understanding of the use of genetically engineered mesenchymal stem cells in human disease therapy with emphasis on genetic modifications aimed to improve survival, homing, angiogenesis, and heart function after myocardial infarction. Advancements in other disease areas are also discussed.

Transplantation of human immature dental pulp stem cell in dogs with chronic spinal cord injury.

PubMed

Feitosa, Matheus Levi Tajra; Sarmento, Carlos Alberto Palmeira; Bocabello, Renato Zonzini; Beltrão-Braga, Patrícia Cristina Baleeiro; Pignatari, Graciela Conceição; Giglio, Robson Fortes; Miglino, Maria Angelica; Orlandin, Jéssica Rodrigues; Ambrósio, Carlos Eduardo

2017-07-01

To investigate the therapeutic potential of human immature dental pulp stem cells in the treatment of chronic spinal cord injury in dogs. Three dogs of different breeds with chronic SCI were presented as animal clinical cases. Human immature dental pulp stem cells were injected at three points into the spinal cord, and the animals were evaluated by limb function and magnetic resonance imaging (MRI) pre and post-operative. There was significant improvement from the limb function evaluated by Olby Scale, though it was not supported by the imaging data provided by MRI and clinical sign and evaluation. Human dental pulp stem cell therapy presents promising clinical results in dogs with chronic spinal cord injuries, if used in association with physical therapy.

Patentability of Stem Cells in the United States.

PubMed

Fendrick, Sarah E; Zuhn, Donald L

2015-08-20

Until recently, the patentability of stem cells was well established within the judicial and statutory framework in the United States. However, the shifting landscape of patent law, particularly with regard to patent-eligible subject matter under 35 U.S.C. §101, presents new challenges to the patentability of stem cells. In this paper, we discuss the legal precedent that paved the way for stem cell patents, including Diamond v. Chakrabarty and In re Bergy. Additionally, we review recent Supreme Court cases and recent guidance issued by the U.S. Patent and Trademark Office that impose new limitations on patent-eligible subject matter and thereby threaten the patentability of stem cells in the United States. Copyright © 2015 Cold Spring Harbor Laboratory Press; all rights reserved.

Human adipose stem cell and ASC-derived cardiac progenitor cellular therapy improves outcomes in a murine model of myocardial infarction

PubMed Central

Davy, Philip MC; Lye, Kevin D; Mathews, Juanita; Owens, Jesse B; Chow, Alice Y; Wong, Livingston; Moisyadi, Stefan; Allsopp, Richard C

2015-01-01

Background Adipose tissue is an abundant and potent source of adult stem cells for transplant therapy. In this study, we present our findings on the potential application of adipose-derived stem cells (ASCs) as well as induced cardiac-like progenitors (iCPs) derived from ASCs for the treatment of myocardial infarction. Methods and results Human bone marrow (BM)-derived stem cells, ASCs, and iCPs generated from ASCs using three defined cardiac lineage transcription factors were assessed in an immune-compromised mouse myocardial infarction model. Analysis of iCP prior to transplant confirmed changes in gene and protein expression consistent with a cardiac phenotype. Endpoint analysis was performed 1 month posttransplant. Significantly increased endpoint fractional shortening, as well as reduction in the infarct area at risk, was observed in recipients of iCPs as compared to the other recipient cohorts. Both recipients of iCPs and ASCs presented higher myocardial capillary densities than either recipients of BM-derived stem cells or the control cohort. Furthermore, mice receiving iCPs had a significantly higher cardiac retention of transplanted cells than all other groups. Conclusion Overall, iCPs generated from ASCs outperform BM-derived stem cells and ASCs in facilitating recovery from induced myocardial infarction in mice. PMID:26604802

Epigenetic modulation of dental pulp stem cells: implications for regenerative endodontics.

PubMed

Duncan, H F; Smith, A J; Fleming, G J P; Cooper, P R

2016-05-01

Dental pulp stem cells (DPSCs) offer significant potential for use in regenerative endodontics, and therefore, identifying cellular regulators that control stem cell fate is critical to devising novel treatment strategies. Stem cell lineage commitment and differentiation are regulated by an intricate range of host and environmental factors of which epigenetic influence is considered vital. Epigenetic modification of DNA and DNA-associated histone proteins has been demonstrated to control cell phenotype and regulate the renewal and pluripotency of stem cell populations. The activities of the nuclear enzymes, histone deacetylases, are increasingly being recognized as potential targets for pharmacologically inducing stem cell differentiation and dedifferentiation. Depending on cell maturity and niche in vitro, low concentration histone deacetylase inhibitor (HDACi) application can promote dedifferentiation of several post-natal and mouse embryonic stem cell populations and conversely increase differentiation and accelerate mineralization in DPSC populations, whilst animal studies have shown an HDACi-induced increase in stem cell marker expression during organ regeneration. Notably, both HDAC and DNA methyltransferase inhibitors have also been demonstrated to dramatically increase the reprogramming of somatic cells to induced pluripotent stem cells (iPSCs) for use in regenerative therapeutic procedures. As the regulation of cell fate will likely remain the subject of intense future research activity, this review aims to describe the current knowledge relating to stem cell epigenetic modification, focusing on the role of HDACi on alteration of DPSC phenotype, whilst presenting the potential for therapeutic application as part of regenerative endodontic regimens. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Concise Review: Fabrication, Customization, and Application of Cell Mimicking Microparticles in Stem Cell Science.

PubMed

Labriola, Nicholas R; Azagury, Aharon; Gutierrez, Robert; Mathiowitz, Edith; Darling, Eric M

2018-02-01

Stem and non-stem cell behavior is heavily influenced by the surrounding microenvironment, which includes other cells, matrix, and potentially biomaterials. Researchers have been successful in developing scaffolds and encapsulation techniques to provide stem cells with mechanical, topographical, and chemical cues to selectively direct them toward a desired differentiation pathway. However, most of these systems fail to present truly physiological replications of the in vivo microenvironments that stem cells are typically exposed to in tissues. Thus, cell mimicking microparticles (CMMPs) have been developed to more accurately recapitulate the properties of surrounding cells while still offering ways to tailor what stimuli are presented. This nascent field holds the promise of reducing, or even eliminating, the need for live cells in select, regenerative medicine therapies, and diagnostic applications. Recent, CMMP-based studies show great promise for the technology, yet only reproduce a small subset of cellular characteristics from among those possible: size, morphology, topography, mechanical properties, surface molecules, and tailored chemical release to name the most prominent. This Review summarizes the strengths, weaknesses, and ideal applications of micro/nanoparticle fabrication and customization methods relevant to cell mimicking and provides an outlook on the future of this technology. Moving forward, researchers should seek to combine multiple techniques to yield CMMPs that replicate as many cellular characteristics as possible, with an emphasis on those that most strongly influence the desired therapeutic effects. The level of flexibility in customizing CMMP properties allows them to substitute for cells in a variety of regenerative medicine, drug delivery, and diagnostic systems. Stem Cells Translational Medicine 2018;7:232-240. © 2018 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

Biophysics and dynamics of natural and engineered stem cell microenvironments.

PubMed

Keung, Albert J; Healy, Kevin E; Kumar, Sanjay; Schaffer, David V

2010-01-01

Stem cells are defined by their ability to self-renew and to differentiate into one or more mature lineages, and they reside within natural niches in many types of adult and embryonic tissues that present them with complex signals to regulate these two hallmark properties. The diverse nature of these in vivo microenvironments raises important questions about the microenvironmental cues regulating stem cell plasticity, and the stem cell field has built a strong foundation of knowledge on the biochemical identities and regulatory effects of the soluble, cellular, and extracellular matrix factors surrounding stem cells through the isolation and culture of stem cells in vitro within microenvironments that, in effect, emulate the properties of the natural niche. Recent work, however, has expanded the field's perspective to include biophysical and dynamic characteristics of the microenvironment. These include biomechanical characteristics such as elastic modulus, shear force, and cyclic strain; architectural properties such as geometry, topography, and dimensionality; and dynamic structures and ligand profiles. We will review how these microenvironmental characteristics have been shown to regulate stem cell fate and discuss future research directions that may help expand our current understanding of stem cell biology and aid its application to regenerative medicine.

Tracing the origins of relapse in acute myeloid leukaemia to stem cells.

PubMed

Shlush, Liran I; Mitchell, Amanda; Heisler, Lawrence; Abelson, Sagi; Ng, Stanley W K; Trotman-Grant, Aaron; Medeiros, Jessie J F; Rao-Bhatia, Abilasha; Jaciw-Zurakowsky, Ivana; Marke, Rene; McLeod, Jessica L; Doedens, Monica; Bader, Gary; Voisin, Veronique; Xu, ChangJiang; McPherson, John D; Hudson, Thomas J; Wang, Jean C Y; Minden, Mark D; Dick, John E

2017-07-06

In acute myeloid leukaemia, long-term survival is poor as most patients relapse despite achieving remission. Historically, the failure of therapy has been thought to be due to mutations that produce drug resistance, possibly arising as a consequence of the mutagenic properties of chemotherapy drugs. However, other lines of evidence have pointed to the pre-existence of drug-resistant cells. For example, deep sequencing of paired diagnosis and relapse acute myeloid leukaemia samples has provided direct evidence that relapse in some cases is generated from minor genetic subclones present at diagnosis that survive chemotherapy, suggesting that resistant cells are generated by evolutionary processes before treatment and are selected by therapy. Nevertheless, the mechanisms of therapy failure and capacity for leukaemic regeneration remain obscure, as sequence analysis alone does not provide insight into the cell types that are fated to drive relapse. Although leukaemia stem cells have been linked to relapse owing to their dormancy and self-renewal properties, and leukaemia stem cell gene expression signatures are highly predictive of therapy failure, experimental studies have been primarily correlative and a role for leukaemia stem cells in acute myeloid leukaemia relapse has not been directly proved. Here, through combined genetic and functional analysis of purified subpopulations and xenografts from paired diagnosis/relapse samples, we identify therapy-resistant cells already present at diagnosis and two major patterns of relapse. In some cases, relapse originated from rare leukaemia stem cells with a haematopoietic stem/progenitor cell phenotype, while in other instances relapse developed from larger subclones of immunophenotypically committed leukaemia cells that retained strong stemness transcriptional signatures. The identification of distinct patterns of relapse should lead to improved methods for disease management and monitoring in acute myeloid leukaemia. Moreover, the shared functional and transcriptional stemness properties that underlie both cellular origins of relapse emphasize the importance of developing new therapeutic approaches that target stemness to prevent relapse.

Adeno-Associated Virus Vectors and Stem Cells: Friends or Foes?

PubMed

Brown, Nolan; Song, Liujiang; Kollu, Nageswara R; Hirsch, Matthew L

2017-06-01

The infusion of healthy stem cells into a patient-termed "stem-cell therapy"-has shown great promise for the treatment of genetic and non-genetic diseases, including mucopolysaccharidosis type 1, Parkinson's disease, multiple sclerosis, numerous immunodeficiency disorders, and aplastic anemia. Stem cells for cell therapy can be collected from the patient (autologous) or collected from another "healthy" individual (allogeneic). The use of allogenic stem cells is accompanied with the potentially fatal risk that the transplanted donor T cells will reject the patient's cells-a process termed "graft-versus-host disease." Therefore, the use of autologous stem cells is preferred, at least from the immunological perspective. However, an obvious drawback is that inherently as "self," they contain the disease mutation. As such, autologous cells for use in cell therapies often require genetic "correction" (i.e., gene addition or editing) prior to cell infusion and therefore the requirement for some form of nucleic acid delivery, which sets the stage for the AAV controversy discussed herein. Despite being the most clinically applied gene delivery context to date, unlike other more concerning integrating and non-integrating vectors such as retroviruses and adenovirus, those based on adeno-associated virus (AAV) have not been employed in the clinic. Furthermore, published data regarding AAV vector transduction of stem cells are inconsistent in regards to vector transduction efficiency, while the pendulum swings far in the other direction with demonstrations of AAV vector-induced toxicity in undifferentiated cells. The variation present in the literature examining the transduction efficiency of AAV vectors in stem cells may be due to numerous factors, including inconsistencies in stem-cell collection, cell culture, vector preparation, and/or transduction conditions. This review summarizes the controversy surrounding AAV vector transduction of stem cells, hopefully setting the stage for future elucidation and eventual therapeutic applications.

Therapeutic cloning and cellular reprogramming.

PubMed

Rodriguez, Ramon M; Ross, Pablo J; Cibelli, Jose B

2012-01-01

Embryonic stem cells are capable of differentiating into any cell-type present in an adult organism, and constitute a renewable source of tissue for regenerative therapies. The transplant of allogenic stem cells is challenging due to the risk of immune rejection. Nevertheless, somatic cell reprogramming techniques allow the generation of isogenic embryonic stem cells, genetically identical to the patient. In this chapter we will discuss the cellular reprogramming techniques in the context of regenerative therapy and the biological and technical barriers that they will need to overcome before clinical use.

Nestin-expressing cells in the pancreatic islets of Langerhans.

PubMed

Hunziker, E; Stein, M

2000-04-29

The pancreatic islets of Langerhans produce several peptide hormones, predominantly the metabolically active hormones insulin and glucagon, which are critical for maintaining normal fuel homeostasis. Some evidence exists that pancreatic endocrine cells turn over at a slow rate and can regenerate in certain conditions. This could be due to the presence of pluripotent cells residing in the pancreas. Recently the intermediate filament protein nestin has been identified to be a marker for a multipotent stem cell in the central nervous system. Given the similarity between the pancreatic islets and neuronal cells, we hypothesized that stem cells expressing nestin might be present in the pancreas. Here we present evidence that a subset of cells in the pancreatic islets express the stem cell marker nestin. These cells might serve as precursors of differentiated pancreatic endocrine cells. Copyright 2000 Academic Press.

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

[Research progress of Lgr5-positive stem cells in the formation of organoid in 3D culture].

PubMed

He, Q Q; Li, A; Wang, M H; Gao, X

2018-06-07

Stem cell is critical to regeneration of tissue or organ of human. How to promote repair or regeneration in the tissues/organ using its pluripotency is always an important issue. Lgr5-possitive cell is one type of the stem cell-like cells capable of pluripotent differentiation in various tissues/organs of both humans and mice. Current study showed that single or small amount Lgr5-possitive stem cells can grow and form a plurality of organs in 3D culture system, and some organs can present similar biological and physiological properties with the progenitor they were derived. These studies provided new insight into future orientation, for example, Lgr5-possitive inner ear cells were confirmed as inner ear pluripotent cells population, the experiences obtained from organoid studies of Lgr5-possitive cells have certainly showed potential in the future study of inner ear stem cells. This review will focus on the recent progress associated with Lgr 5-positive stem cells forming organoids in the 3D culture.

The role of CD133 in normal human prostate stem cells and malignant cancer-initiating cells.

PubMed

Vander Griend, Donald J; Karthaus, Wouter L; Dalrymple, Susan; Meeker, Alan; DeMarzo, Angelo M; Isaacs, John T

2008-12-01

Resolving the specific cell of origin for prostate cancer is critical to define rational targets for therapeutic intervention and requires the isolation and characterization of both normal human prostate stem cells and prostate cancer-initiating cells (CIC). Single epithelial cells from fresh normal human prostate tissue and prostate epithelial cell (PrEC) cultures derived from them were evaluated for the presence of subpopulations expressing stem cell markers and exhibiting stem-like growth characteristics. When epithelial cell suspensions containing cells expressing the stem cell marker CD133+ are inoculated in vivo, regeneration of stratified human prostate glands requires inductive prostate stromal cells. PrEC cultures contain a small subpopulation of CD133+ cells, and fluorescence-activated cell sorting-purified CD133+ PrECs self-renew and regenerate cell populations expressing markers of transit-amplifying cells (DeltaNp63), intermediate cells (prostate stem cell antigen), and neuroendocrine cells (CD56). Using a series of CD133 monoclonal antibodies, attachment and growth of CD133+ PrECs requires surface expression of full-length glycosylated CD133 protein. Within a series of androgen receptor-positive (AR+) human prostate cancer cell lines, CD133+ cells are present at a low frequency, self-renew, express AR, generate phenotypically heterogeneous progeny negative for CD133, and possess an unlimited proliferative capacity, consistent with CD133+ cells being CICs. Unlike normal adult prostate stem cells, prostate CICs are AR+ and do not require functional CD133. This suggests that (a) AR-expressing prostate CICs are derived from a malignantly transformed intermediate cell that acquires "stem-like activity" and not from a malignantly transformed normal stem cell and (b) AR signaling pathways are a therapeutic target for prostate CICs.

Relapsing tumefactive lesion in an adult with medulloblastoma previously treated with chemoradiotherapy and stem cell transplant.

PubMed

Mahta, Ali; Qu, Yan; Nastic, Denis; Sundstrom, Maria; Kim, Ryan Y; Saria, Marlon; Santagata, Sandro; Kesari, Santosh

2012-04-01

Herein, we present an adult case of medulloblastoma who received chemotherapy, radiation therapy and stem cell transplantation, and underwent multiple surgical resections for what were thought to be recurrences; however pathology confirmed a diagnosis of relapsing tumefactive lesions. This phenomenon seems to be a consequence of stem cell transplantation rather than a simple radiation treatment effect.

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

PubMed

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

2016-06-01

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

Evaluation of the maintenance of stemness, viability, and differentiation potential of gingiva-derived stem-cell spheroids.

PubMed

Lee, Sung-Il; Ko, Youngkyung; Park, Jun-Beom

2017-05-01

Gingiva-derived stem cells have been applied for tissue-engineering purposes and may be considered a favorable source of mesenchymal stem cells as harvesting stem cells from the mandible or maxilla may be performed with ease under local anesthesia. The present study was performed to fabricate stem-cell spheroids using concave microwells and to evaluate the maintenance of stemness, viability, and differentiation potential. Gingiva-derived stem cells were isolated, and the stem cells of 4×10 5 (group A) or 8×10 5 (group B) cells were seeded into polydimethylsiloxane-based, concave micromolds with 600 µm diameters. The morphology of the microspheres and the change of the diameters of the spheroids were evaluated. The viability of spheroids was qualitatively analyzed via Live/Dead kit assay. A cell viability analysis was performed on days 1, 3, 6, and 12 with Cell Counting Kit-8. The maintenance of stemness was evaluated with immunocytochemical staining using SSEA-4, TRA-1-60(R) (positive markers), and SSEA-1 (negative marker). Osteogenic, adipogenic, and chondrogenic differentiation potential was evaluated by incubating spheroids in osteogenic, adipogenic and chondrogenic induction medium, respectively. The gingiva-derived stem cells formed spheroids in the concave microwells. The diameters of the spheroids were larger in group A than in group B. The majority of cells in the spheroids emitted green fluorescence, indicating the presence of live cells at day 6. At day 12, the majority of cells in the spheroids emitted green fluorescence, and a small portion of red fluorescence was also noted, which indicated the presence of dead cells. The spheroids were positive for the stem-cell markers SSEA-4 and TRA-1-60(R) and were negative for SSEA-1, suggesting that these spheroids primarily contained undifferentiated human stem cells. Osteogenic, adipogenic, and chondrogenic differentiation was more evident with an increase of incubation time: Mineralized extracellular deposits were observed following Alizarin Red S staining at days 14 and 21; oil globules were increased at day 18 when compared with day 6; and Alcian blue staining was more evident at day 18 when compared with day 6. Within the limits of this study, stem-cell spheroids from gingival cells maintained the stemness, viability, and differentiation potential during the experimental periods. This method may be applied for a promising strategy for stem-cell therapy.

Temporal and spatial changes of cells positive for stem-like markers in different compartments and stages of human colorectal adenoma-carcinoma sequence

PubMed Central

Cui, Guanglin; Xu, Gang; Zhu, Li; Pang, Zhigang; Zheng, Wei; Li, Zhenfeng; Yuan, Aping

2017-01-01

Considerable evidence supports the idea that stem-like cells may play an essential role during the development of colorectal cancer (CRC). To accomplish this aim, we use immunohistochemistry (IHC) and double IHC with different potential stem-like markers, anti-musashi (Msi), anti-CD133, anti- LGR5 and anti-ALDH1 to examine the presentation of stem-like cells in different compartments including adenoma/CRC epithelium, transitional crypts and tumor stroma in colorectal adenoma and CRC. The results showed that cells positive for stem-like markers were remarkably increased in number and frequently observed in the adenoma/CRC epithelium, transitional crypts and tumor stroma. Notably, the population of cells positive for stem-liker markers was expanded from the base to the middle part of the transitional crypt in both adenoma and CRC tissues, reflecting that stem-like cells are likely involved in the process of colorectal tumorigenesis. Counting results showed that the grading scores of cells positive for LGR5 and ALDH1 in the adenoma/CRC epithelium were significantly increased relative with the control epithelium, and associated with the degree of dysplasia in the adenoma and node involvement in the CRC (all P < 0.05). In addition, the density of cells positive for stem–like markers in the adenomatous/cancerous stroma was also increased and paralleled an increase in the density of proliferative stromal cells labeled by PCNA, which were primarily identified as vimentin positive fibroblasts. Our results have revealed a changed temporal and spatial presentation of stem-like markers in different stages of human colorectal adenoma-carcinoma sequence, which might be a hallmark of the adenoma-carcinoma transition. PMID:28484082

Surface presentation of biochemical cues for stem cell expansion - Spatial distribution of growth factors and self-assembly of extracellular matrix

NASA Astrophysics Data System (ADS)

Liu, Xingyu

Despite its great potential applications to stem cell technology and tissue engineering, matrix presentation of biochemical cues such as growth factors and extracellular matrix (ECM) components remains undefined. This is largely due to the difficulty in preserving the bioactivities of signaling molecules and in controlling the spatial distribution, cellular accessibility, molecular orientation and intermolecular assembly of the biochemical cues. This dissertation comprises of two parts that focuses on understanding surface presentation of a growth factor and ECM components, respectively. This dissertation addresses two fundamental questions in stem cell biology using two biomaterials platforms. How does nanoscale distribution of growth factor impact signaling activation and cellular behaviors of adult neural stem cells? How does ECM self-assembly impact human embryonic stem cell survival and proliferation? The first question was addressed by the design of a novel quantitative platform that allows the control of FGF-2 molecular presentation locally as either monomers or clusters when tethered to a polymeric substrate. This substrate-tethered FGF-2 enables a switch-like signaling activation in response to dose titration of FGF-2. This is in contrast to a continuous MAPK activation pattern elicited by soluble FGF-2. Consequently, cell proliferation, and spreading were also consistent with this FGF-2 does-response pattern. We demonstrated that the combination of FGF-2 concentration and its cluster size, rather than concentration alone, serves as the determinants to govern its biological effect on neural stem cells. The second part of this dissertation was inspired by the challenge that hESCs have extremely low clonal efficiency and hESC survival is critically dependent on cell substrate adhesion. We postulated that ECM integrity is a critical factor in preventing hESC anchorage-dependent apoptosis, and that the matrix for feeder-free culture need to be properly assembled in order to mimic the stem cell niche in vivo. First, we established assays that allow high-throughput quantification of hESC proliferation and ECM deposition. Human ESC survival was found to be highly sensitive to ECM assembly, and was improved by at least 20 times on substrates with well-assembled ECM. ECM polymerization alone improves clonal efficiency by at least 20 fold, from less than 0.1% to be 3-5%. This ratio is further improved to greater than 35% when combined with ROCK inhibitor, suggesting ECM polymerization underlines another critical factor in dictating hESC survival and growth. Given that many important signaling molecules including growth factors and extracellular matrix are highly enriched and restricted at the stem cell niche, we anticipate that our investigation into these questions provides better insight into the physiological roles of the stem cell niche components, and helps us to rationally direct stem cell fates in future stem cell-based therapeutic interventions.

PERSPECTIVES ON CANCER STEM CELLS IN OSTEOSARCOMA

PubMed Central

Basu-Roy, Upal; Basilico, Claudio; Mansukhani, Alka

2012-01-01

Osteosarcoma is an aggressive pediatric tumor of growing bones that, despite surgery and chemotherapy, is prone to relapse. These mesenchymal tumors are derived from progenitor cells in the osteoblast lineage that have accumulated mutations to escape cell cycle checkpoints leading to excessive proliferation and defects in their ability to differentiate appropriately into mature bone-forming osteoblasts. Like other malignant tumors, osteosarcoma is often heterogeneous, consisting of phenotypically distinct cells with features of different stages of differentiation. The cancer stem cell hypothesis posits that tumors are maintained by stem cells and it is the incomplete eradication of a refractory population of tumor-initiating stem cells that accounts for drug resistance and tumor relapse. In this review we present our current knowledge about the biology of osteosarcoma stem cells from mouse and human tumors, highlighting new insights and unresolved issues in the identification of this elusive population. We focus on factors and pathways that are implicated in maintaining such cells, and differences from paradigms of epithelial cancers. Targeting of the cancer stem cells in osteosarcoma is a promising avenue to explore to develop new therapies for this devastating childhood cancer. PMID:22659734

Lung bioengineering: physical stimuli and stem/progenitor cell biology interplay towards biofabricating a functional organ.

PubMed

Nonaka, Paula N; Uriarte, Juan J; Campillo, Noelia; Oliveira, Vinicius R; Navajas, Daniel; Farré, Ramon

2016-11-28

A current approach to obtain bioengineered lungs as a future alternative for transplantation is based on seeding stem cells on decellularized lung scaffolds. A fundamental question to be solved in this approach is how to drive stem cell differentiation onto the different lung cell phenotypes. Whereas the use of soluble factors as agents to modulate the fate of stem cells was established from an early stage of the research with this type of cells, it took longer to recognize that the physical microenvironment locally sensed by stem cells (e.g. substrate stiffness, 3D architecture, cyclic stretch, shear stress, air-liquid interface, oxygenation gradient) also contributes to their differentiation. The potential role played by physical stimuli would be particularly relevant in lung bioengineering since cells within the organ are physiologically subjected to two main stimuli required to facilitate efficient gas exchange: air ventilation and blood perfusion across the organ. The present review focuses on describing how the cell mechanical microenvironment can modulate stem cell differentiation and how these stimuli could be incorporated into lung bioreactors for optimizing organ bioengineering.

Dynamics associated with spontaneous differentiation of ovarian stem cells in vitro

PubMed Central

2014-01-01

Background Recent studies suggest that ovarian germ line stem cells replenish oocyte-pool in adult stage, and challenge the central doctrine of ‘fixed germ cell pool’ in mammalian reproductive biology. Two distinct populations of spherical stem cells with high nucleo-cytoplasmic ratio have been recently identified in the adult mammalian ovary surface epithelium (OSE) including nuclear OCT-4A positive very small embryonic-like (VSELs) and cytoplasmic OCT-4 expressing ovarian germ stem cells (OGSCs). Three weeks culture of scraped OSE cells results in spontaneous differentiation of the stem cells into oocyte-like, parthenote-like, embryoid body-like structures and also embryonic stem cell-like colonies whereas epithelial cells attach and transform into a bed of mesenchymal cells. Present study was undertaken, to further characterize ovarian stem cells and to comprehend better the process of spontaneous differentiation of ovarian stem cells into oocyte-like structures in vitro. Methods Ovarian stem cells were enriched by immunomagnetic sorting using SSEA-4 as a cell surface marker and were further characterized. Stem cells and clusters of OGSCs (reminiscent of germ cell nests in fetal ovaries), were characterized by immuno-localization for stem and germ cell specific markers and spontaneous differentiation in OSE cultures was studied by live cell imaging. Results Differential expression of markers specific for pluripotent VSELs (nuclear OCT-4A, SSEA-4, CD133), OGSCs (cytoplasmic OCT-4) primordial germ cells (FRAGILIS, STELLA, VASA) and germ cells (DAZL, GDF-9, SCP-3) were studied. Within one week of culture, stem cells became bigger in size, developed abundant cytoplasm, differentiated into germ cells, revealed presence of Balbiani body-like structure (mitochondrial cloud) and exhibited characteristic cytoplasmic streaming. Conclusions Presence of germ cell nests, Balbiani body-like structures and cytoplasmic streaming extensively described during fetal ovary development, are indeed well recapitulated during in vitro oogenesis in adult OSE cultures along with characteristic expression of stem/germ cell/oocyte markers. Further studies are required to assess the genetic integrity of in vitro derived oocytes before harnessing their clinical potential. Advance in our knowledge about germ cell differentiation from stem cells will enable researchers to design better in vitro strategies which in turn may have relevance to reproductive biology and regenerative medicine. PMID:24568237

Electroactive 3D materials for cardiac tissue engineering

NASA Astrophysics Data System (ADS)

Gelmi, Amy; Zhang, Jiabin; Cieslar-Pobuda, Artur; Ljunngren, Monika K.; Los, Marek Jan; Rafat, Mehrdad; Jager, Edwin W. H.

2015-04-01

By-pass surgery and heart transplantation are traditionally used to restore the heart's functionality after a myocardial Infarction (MI or heart attack) that results in scar tissue formation and impaired cardiac function. However, both procedures are associated with serious post-surgical complications. Therefore, new strategies to help re-establish heart functionality are necessary. Tissue engineering and stem cell therapy are the promising approaches that are being explored for the treatment of MI. The stem cell niche is extremely important for the proliferation and differentiation of stem cells and tissue regeneration. For the introduction of stem cells into the host tissue an artificial carrier such as a scaffold is preferred as direct injection of stem cells has resulted in fast stem cell death. Such scaffold will provide the proper microenvironment that can be altered electronically to provide temporal stimulation to the cells. We have developed an electroactive polymer (EAP) scaffold for cardiac tissue engineering. The EAP scaffold mimics the extracellular matrix and provides a 3D microenvironment that can be easily tuned during fabrication, such as controllable fibre dimensions, alignment, and coating. In addition, the scaffold can provide electrical and electromechanical stimulation to the stem cells which are important external stimuli to stem cell differentiation. We tested the initial biocompatibility of these scaffolds using cardiac progenitor cells (CPCs), and continued onto more sensitive induced pluripotent stem cells (iPS). We present the fabrication and characterisation of these electroactive fibres as well as the response of increasingly sensitive cell types to the scaffolds.

Predicting gene regulatory networks by combining spatial and temporal gene expression data in Arabidopsis root stem cells

PubMed Central

de Luis Balaguer, Maria Angels; Fisher, Adam P.; Clark, Natalie M.; Fernandez-Espinosa, Maria Guadalupe; Möller, Barbara K.; Weijers, Dolf; Williams, Cranos; Lorenzo, Oscar; Sozzani, Rosangela

2017-01-01

Identifying the transcription factors (TFs) and associated networks involved in stem cell regulation is essential for understanding the initiation and growth of plant tissues and organs. Although many TFs have been shown to have a role in the Arabidopsis root stem cells, a comprehensive view of the transcriptional signature of the stem cells is lacking. In this work, we used spatial and temporal transcriptomic data to predict interactions among the genes involved in stem cell regulation. To accomplish this, we transcriptionally profiled several stem cell populations and developed a gene regulatory network inference algorithm that combines clustering with dynamic Bayesian network inference. We leveraged the topology of our networks to infer potential major regulators. Specifically, through mathematical modeling and experimental validation, we identified PERIANTHIA (PAN) as an important molecular regulator of quiescent center function. The results presented in this work show that our combination of molecular biology, computational biology, and mathematical modeling is an efficient approach to identify candidate factors that function in the stem cells. PMID:28827319

Wnt Signaling in Adult Epithelial Stem Cells and Cancer.

PubMed

Tan, Si Hui; Barker, Nick

2018-01-01

Wnt/β-catenin signaling is integral to the homeostasis and regeneration of many epithelial tissues due to its critical role in adult stem cell regulation. It is also implicated in many epithelial cancers, with mutations in core pathway components frequently present in patient tumors. In this chapter, we discuss the roles of Wnt/β-catenin signaling and Wnt-regulated stem cells in homeostatic, regenerative and cancer contexts of the intestines, stomach, skin, and liver. We also examine the sources of Wnt ligands that form part of the stem cell niche. Despite the diversity in characteristics of various tissue stem cells, the role(s) of Wnt/β-catenin signaling is generally coherent in maintaining stem cell fate and/or promoting proliferation. It is also likely to play similar roles in cancer stem cells, making the pathway a salient therapeutic target for cancer. While promising progress is being made in the field, deeper understanding of the functions and signaling mechanisms of the pathway in individual epithelial tissues will expedite efforts to modulate Wnt/β-catenin signaling in cancer treatment and tissue regeneration. Copyright © 2018 Elsevier Inc. All rights reserved.

The Role of Stem Cell Therapeutics in Wound Healing: Current Understanding and Future Directions.

PubMed

Sorice, Sarah; Rustad, Kristine C; Li, Alexander Y; Gurtner, Geoffrey C

2016-09-01

Chronic wounds present unique challenges for healthcare providers as they place patients at increased risk for various morbidities and mortality. Advances in wound care technology have expanded the treatment options available for wound management, but few products fully address the underlying core deficiencies responsible for the development of poorly healing wounds. In the future, addressing these derangements will undoubtedly play a key role in the treatment of these patients. Broad enthusiasm has surrounded the field of stem cell biology, which has shown great promise in repairing damaged tissues across numerous disease phenotypes. In this review, we provide a comprehensive review of the literature and evaluate the present landscape of wound therapeutics while discussing the rationales and allure behind stem cell-based products. We further propose 2 challenges that remain as new stem cell-based therapies are being developed and as this technology moves toward clinical translation. Given the relatively young age of this newer technology in wound healing, numerous challenges continue to surround its effective use including identifying the ideal population of stem cells to use and determining the optimal cell delivery method. However, significant forward progress has been made, with several clinical trials beginning to demonstrate reliable clinical benefit. The upward trajectory of stem cell technologies provides an exciting opportunity to positively impact patient outcomes through the controlled application of regenerative cell-based therapy.

Exploring the regulatory role of isocitrate dehydrogenase mutant protein on glioma stem cell proliferation.

PubMed

Lu, H-C; Ma, J; Zhuang, Z; Qiu, F; Cheng, H-L; Shi, J-X

2016-08-01

Glioma is the most lethal form of cancer that originates mostly from the brain and less frequently from the spine. Glioma is characterized by abnormal regulation of glial cell differentiation. The severity of the glioma was found to be relaxed in isocitrate dehydrogenase 1 (IDH1) mutant. The present study focused on histological discrimination and regulation of cancer stem cell between IDH1 mutant and in non-IDH1 mutant glioma tissue. Histology, immunohistochemistry and Western blotting techniques are used to analyze the glioma nature and variation in glioma stem cells that differ between IDH1 mutant and in non-IDH1 mutant glioma tissue. The aggressive form of non-IDH1 mutant glioma shows abnormal cellular histological variation with prominent larger nucleus along with abnormal clustering of cells. The longer survival form of IDH1 mutant glioma has a control over glioma stem cell proliferation. Immunohistochemistry with stem cell markers, CD133 and EGFRvIII are used to demonstrate that the IDH1 mutant glioma shows limited dependence on cancer stem cells and it shows marked apoptotic signals in TUNEL assay to regulate abnormal cells. The non-IDH1 mutant glioma failed to regulate misbehaving cells and it promotes cancer stem cell proliferation. Our finding supports that the IDH1 mutant glioma has a regulatory role in glioma stem cells and their survival.

The novel tumour suppressor Madm regulates stem cell competition in the Drosophila testis

PubMed Central

Singh, Shree Ram; Liu, Ying; Zhao, Jiangsha; Zeng, Xiankun; Hou, Steven X.

2016-01-01

Stem cell competition has emerged as a mechanism for selecting fit stem cells/progenitors and controlling tumourigenesis. However, little is known about the underlying molecular mechanism. Here we identify Mlf1-adaptor molecule (Madm), a novel tumour suppressor that regulates the competition between germline stem cells (GSCs) and somatic cyst stem cells (CySCs) for niche occupancy. Madm knockdown results in overexpression of the EGF receptor ligand vein (vn), which further activates EGF receptor signalling and integrin expression non-cell autonomously in CySCs to promote their overproliferation and ability to outcompete GSCs for niche occupancy. Conversely, expressing a constitutively activated form of the Drosophila JAK kinase (hopTum−l) promotes Madm nuclear translocation, and suppresses vn and integrin expression in CySCs that allows GSCs to outcompete CySCs for niche occupancy and promotes GSC tumour formation. Tumour suppressor-mediated stem cell competition presented here could be a mechanism of tumour initiation in mammals. PMID:26792023

The novel tumour suppressor Madm regulates stem cell competition in the Drosophila testis.

PubMed

Singh, Shree Ram; Liu, Ying; Zhao, Jiangsha; Zeng, Xiankun; Hou, Steven X

2016-01-21

Stem cell competition has emerged as a mechanism for selecting fit stem cells/progenitors and controlling tumourigenesis. However, little is known about the underlying molecular mechanism. Here we identify Mlf1-adaptor molecule (Madm), a novel tumour suppressor that regulates the competition between germline stem cells (GSCs) and somatic cyst stem cells (CySCs) for niche occupancy. Madm knockdown results in overexpression of the EGF receptor ligand vein (vn), which further activates EGF receptor signalling and integrin expression non-cell autonomously in CySCs to promote their overproliferation and ability to outcompete GSCs for niche occupancy. Conversely, expressing a constitutively activated form of the Drosophila JAK kinase (hop(Tum-l)) promotes Madm nuclear translocation, and suppresses vn and integrin expression in CySCs that allows GSCs to outcompete CySCs for niche occupancy and promotes GSC tumour formation. Tumour suppressor-mediated stem cell competition presented here could be a mechanism of tumour initiation in mammals.

Concentration dependent survival and neural differentiation of murine embryonic stem cells cultured on polyethylene glycol dimethacrylate hydrogels possessing a continuous concentration gradient of n-cadherin derived peptide His-Ala-Val-Asp-Lle.

PubMed

Lim, Hyun Ju; Mosley, Matthew C; Kurosu, Yuki; Smith Callahan, Laura A

2017-07-01

N-cadherin cell-cell signaling plays a key role in the structure and function of the nervous system. However, few studies have incorporated bioactive signaling from n-cadherin into tissue engineering matrices. The present study uses a continuous gradient approach in polyethylene glycol dimethacrylate hydrogels to identify concentration dependent effects of n-cadherin peptide, His-Ala-Val-Asp-Lle (HAVDI), on murine embryonic stem cell survival and neural differentiation. The n-cadherin peptide was found to affect the expression of pluripotency marker, alkaline phosphatase, in murine embryonic stem cells cultured on n-cadherin peptide containing hydrogels in a concentration dependent manner. Increasing n-cadherin peptide concentrations in the hydrogels elicited a biphasic response in neurite extension length and mRNA expression of neural differentiation marker, neuron-specific class III β-tubulin, in murine embryonic stem cells cultured on the hydrogels. High concentrations of n-cadherin peptide in the hydrogels were found to increase the expression of apoptotic marker, caspase 3/7, in murine embryonic stem cells compared to that of murine embryonic stem cell cultures on hydrogels containing lower concentrations of n-cadherin peptide. Increasing the n-cadherin peptide concentration in the hydrogels facilitated greater survival of murine embryonic stem cells exposed to increasing oxidative stress caused by hydrogen peroxide exposure. The combinatorial approach presented in this work demonstrates concentration dependent effects of n-cadherin signaling on mouse embryonic stem cell behavior, underscoring the need for the greater use of systematic approaches in tissue engineering matrix design in order to understand and optimize bioactive signaling in the matrix for tissue formation. Single cell encapsulation is common in tissue engineering matrices. This eliminates cellular access to cell-cell signaling. N-cadherin, a cell-cell signaling molecule, plays a vital role in the development of neural tissues, but has not been well studied as a bioactive signaling element in neural tissue engineering matrices. The present study uses a systematic continuous gradient approach to identify concentration dependent effects of n-cadherin derived peptide, HAVDI, on the survival and neural differentiation of murine embryonic stem cells. This work underscores the need for greater use to combinatorial strategies to understand the effect complex bioactive signaling, such as n-cadherin, and the need to optimize the concentration of such bioactive signaling within tissue engineering matrices for maximal cellular response. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Directing stem cell fate on hydrogel substrates by controlling cell geometry, matrix mechanics and adhesion ligand composition.

PubMed

Lee, Junmin; Abdeen, Amr A; Zhang, Douglas; Kilian, Kristopher A

2013-11-01

There is a dynamic relationship between physical and biochemical signals presented in the stem cell microenvironment to guide cell fate determination. Model systems that modulate cell geometry, substrate stiffness or matrix composition have proved useful in exploring how these signals influence stem cell fate. However, the interplay between these physical and biochemical cues during differentiation remains unclear. Here, we demonstrate a microengineering strategy to vary single cell geometry and the composition of adhesion ligands - on substrates that approximate the mechanical properties of soft tissues - to study adipogenesis and neurogenesis in adherent mesenchymal stem cells. Cells cultured in small circular islands show elevated expression of adipogenesis markers while cells that spread in anisotropic geometries tend to express elevated neurogenic markers. Arraying different combinations of matrix protein in a myriad of 2D and pseudo-3D geometries reveals optimal microenvironments for controlling the differentiation of stem cells to these "soft" lineages without the use of media supplements. © 2013 Elsevier Ltd. All rights reserved.

Stem cells and calcium signaling.

PubMed

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

2012-01-01

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

Allometric Scaling of the Active Hematopoietic Stem Cell Pool across Mammals

PubMed Central

Dingli, David; Pacheco, Jorge M.

2006-01-01

Background Many biological processes are characterized by allometric relations of the type Y = Y 0 Mb between an observable Y and body mass M, which pervade at multiple levels of organization. In what regards the hematopoietic stem cell pool, there is experimental evidence that the size of the hematopoietic stem cell pool is conserved in mammals. However, demands for blood cell formation vary across mammals and thus the size of the active stem cell compartment could vary across species. Methodology/Principle Findings Here we investigate the allometric scaling of the hematopoietic system in a large group of mammalian species using reticulocyte counts as a marker of the active stem cell pool. Our model predicts that the total number of active stem cells, in an adult mammal, scales with body mass with the exponent ¾. Conclusion/Significance The scaling predicted here provides an intuitive justification of the Hayflick hypothesis and supports the current view of a small active stem cell pool supported by a large, quiescent reserve. The present scaling shows excellent agreement with the available (indirect) data for smaller mammals. The small size of the active stem cell pool enhances the role of stochastic effects in the overall dynamics of the hematopoietic system. PMID:17183646

FSH-FSHR3-stem cells in ovary surface epithelium: basis for adult ovarian biology, failure, aging, and cancer.

PubMed

Bhartiya, Deepa; Singh, Jarnail

2015-01-01

Despite extensive research, genetic basis of premature ovarian failure (POF) and ovarian cancer still remains elusive. It is indeed paradoxical that scientists searched for mutations in FSH receptor (FSHR) expressed on granulosa cells, whereas more than 90% of cancers arise in ovary surface epithelium (OSE). Two distinct populations of stem cells including very small embryonic-like stem cells (VSELs) and ovarian stem cells (OSCs) exist in OSE, are responsible for neo-oogenesis and primordial follicle assembly in adult life, and are modulated by FSH via its alternatively spliced receptor variant FSHR3 (growth factor type 1 receptor acting via calcium signaling and the ERK/MAPK pathway). Any defect in FSH-FSHR3-stem cell interaction in OSE may affect folliculogenesis and thus result in POF. Ovarian aging is associated with a compromised microenvironment that does not support stem cell differentiation into oocytes and further folliculogenesis. FSH exerts a mitogenic effect on OSE and elevated FSH levels associated with advanced age may provide a continuous trigger for stem cells to proliferate resulting in cancer, thus supporting gonadotropin theory for ovarian cancer. Present review is an attempt to put adult ovarian biology, POF, aging, and cancer in the perspective of FSH-FSHR3-stem cell network that functions in OSE. This hypothesis is further supported by the recent understanding that: i) cancer is a stem cell disease and OSE is the niche for ovarian cancer stem cells; ii) ovarian OCT4-positive stem cells are regulated by FSH; and iii) OCT4 along with LIN28 and BMP4 are highly expressed in ovarian cancers. © 2015 Society for Reproduction and Fertility.

Chemical Activation of the Hypoxia-Inducible Factor Reversibly Reduces Tendon Stem Cell Proliferation, Inhibits Their Differentiation, and Maintains Cell Undifferentiation

PubMed Central

Creo, Pasquale; Bergante, Sonia; Conforti, Erika; Banfi, Giuseppe

2018-01-01

Adult stem cell-based therapeutic approaches for tissue regeneration have been proposed for several years. However, adult stem cells are usually limited in number and difficult to be expanded in vitro, and they usually tend to quickly lose their potency with passages, as they differentiate and become senescent. Culturing stem cells under reduced oxygen tensions (below 21%) has been proposed as a tool to increase cell proliferation, but many studies reported opposite effects. In particular, cell response to hypoxia seems to be very stem cell type specific. Nonetheless, it is clear that a major role in this process is played by the hypoxia inducible factor (HIF), the master regulator of cell response to oxygen deprivation, which affects cell metabolism and differentiation. Herein, we report that a chemical activation of HIF in human tendon stem cells reduces their proliferation and inhibits their differentiation in a reversible and dose-dependent manner. These results support the notion that hypoxia, by activating HIF, plays a crucial role in preserving stem cells in an undifferentiated state in the “hypoxic niches” present in the tissue in which they reside before migrating in more oxygenated areas to heal a damaged tissue. PMID:29713352

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

Cancer stem cell-targeted therapeutics and delivery strategies.

PubMed

Ahmad, Gulzar; Amiji, Mansoor M

2017-08-01

Cancer initiating or stem cells (CSCs) are a small population of cells in the tumor mass, which have been reported to be present in different types of cancers. CSCs usually reside within the tumor and are responsible for reoccurrence of cancer. The imprecise, inaccessible nature and increased efflux of conventional therapeutic drugs make these cells resistant to drugs. We discuss the specific markers for identification of these cells, role of CSCs in chemotherapy resistance and use of different therapeutic means to target them, including elucidation of specific cell markers, exploitation of different signaling pathways and use of nanotechnology. Area covered: This review covers cancer stem cell signaling which are used by these cells to maintain their quiescence, stemness and resistant phenotype, distinct cell surface markers, contribution of these cells in drug resistance, inevitability to cure cancer and use of nanotechnology to overcome this hurdle. Expert opinion: Cancer stem cells are the main culprit of our failure to cure cancer. In order to cure cancer along with other cells types in cancer, cancer stem cells need to be targeted in the tumor bed. Nanotechnology solutions can facilitate clinical translation of the therapeutics along with other emerging technologies to cure cancer.

Label-free detection of surface markers on stem cells by oblique-incidence reflectivity difference microscopy

PubMed Central

Lo, Kai-Yin; Sun, Yung-Shin; Landry, James P.; Zhu, Xiangdong; Deng, Wenbin

2012-01-01

Conventional fluorescent microscopy is routinely used to detect cell surface markers through fluorophore-conjugated antibodies. However, fluorophore-conjugation of antibodies alters binding properties such as strength and specificity of the antibody in ways often uncharacterized. The binding between antibody and antigen might not be in the native situation after such conjugation. Here, we present an oblique-incidence reflectivity difference (OI-RD) microscope as an effective method for label-free, real-time detection of cell surface markers and apply such a technique to analysis of Stage-Specific Embryonic Antigen 1 (SSEA1) on stem cells. Mouse stem cells express SSEA1 on their surfaces and the level of SSEA1 decreases when the cells start to differentiate. In this study, we immobilized mouse stem cells and non-stem cells (control) on a glass surface as a microarray and reacted the cell microarray with unlabeled SSEA1 antibodies. By monitoring the reaction with an OI-RD microscope in real time, we confirmed that the SSEA1 antibodies only bind to the surface of the stem cells while not to the surface of non-stem cells. From the binding curves, we determined the equilibrium dissociation constant (Kd) of the antibody with the SSEA1 markers on the stem cell surface. The results concluded that OI-RD microscope can be used to detect binding affinities between cell surface markers and unlabeled antibodies bound to the cells. The information could be another indicator to determine the cell stages. PMID:21781038

Vitrification of mouse embryo-derived ICM cells: a tool for preserving embryonic stem cell potential?

PubMed

Desai, Nina; Xu, Jing; Tsulaia, Tamara; Szeptycki-Lawson, Julia; AbdelHafez, Faten; Goldfarb, James; Falcone, Tommaso

2011-02-01

Vitrification technology presents new opportunities for preservation of embryo derived stem cells without first establishing a viable ESC line. This study tests the feasibility of cryopreserving ICM cells using vitrification. ICMs from mouse embryos were isolated and vitrified in HSV straws or on cryoloops. Upon warming, the vitrified ICMs were cultured and observed for attachment and morphology. Colonies were passaged every 3-6 days. ICMs and ICM-derived ESC colonies were tested for expression of stem cell specific markers. ICMs vitrified on both the cryoloop and the HSV straw had high survival rates. ICM derived ESCs remained undifferentiated for several passages and demonstrated expression of typical stem cell markers; SSEA-1, Sox-2, Oct 4 and alkaline phosphatase. This is the first report on successful vitrification of isolated ICMs and the subsequent derivation of ESC colonies. Vitrification of isolated ICMs is a novel approach for preservation of the "stem cell source" material.

Anticarcinogenic activity of polyphenolic extracts from grape stems against breast, colon, renal and thyroid cancer cells.

PubMed

Sahpazidou, Despina; Geromichalos, George D; Stagos, Dimitrios; Apostolou, Anna; Haroutounian, Serkos A; Tsatsakis, Aristidis M; Tzanakakis, George N; Hayes, A Wallace; Kouretas, Dimitrios

2014-10-15

A major part of the wineries' wastes is composed of grape stems which are discarded mainly in open fields and cause environmental problems due mainly to their high polyphenolic content. The grape stem extracts' use as a source of high added value polyphenols presents great interest because this combines a profitable venture with environmental protection close to wine-producing zones. In the present study, at first, the Total Polyphenolic Content (TPC) and the polyphenolic composition of grape stem extracts from four different Greek Vitis vinifera varieties were determined by HPLC methods. Afterwards, the grape stem extracts were examined for their ability to inhibit growth of colon (HT29), breast (MCF-7 and MDA-MB-23), renal (786-0 and Caki-1) and thyroid (K1) cancer cells. The cancer cells were exposed to the extracts for 72 h and the effects on cell growth were evaluated using the SRB assay. The results indicated that all extracts inhibited cell proliferation, with IC₅₀ values of 121-230 μg/ml (MCF-7), 121-184 μg/ml (MDA-MD-23), 175-309 μg/ml (HT29), 159-314 μg/ml (K1), 180-225 μg/ml (786-0) and 134->400 μg/ml (Caki-1). This is the first study presenting the inhibitory activity of grape stem extracts against growth of colon, breast, renal and thyroid cancer cells. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Synthetic and biogenic magnetite nanoparticles for tracking of stem cells and dendritic cells

NASA Astrophysics Data System (ADS)

Schwarz, Sebastian; Fernandes, Fabiana; Sanroman, Laura; Hodenius, Michael; Lang, Claus; Himmelreich, Uwe; Schmitz-Rode, Thomas; Schueler, Dirk; Hoehn, Mathias; Zenke, Martin; Hieronymus, Thomas

2009-05-01

Accurate delivery of cells to target organs is critical for success of cell-based therapies with stem cells or immune cells such as antigen-presenting dendritic cells (DC). Labeling with contrast agents before implantation provides a powerful means for monitoring cellular migration using magnetic resonance imaging (MRI). In this study, we investigated the uptake of fully synthesized or bacterial magnetic nanoparticles (MNPs) into hematopoietic Flt3 + stem cells and DC from mouse bone marrow. We show that (i) uptake of both synthetic and biogenic nanoparticles into cells endow magnetic activity and (ii) low numbers of MNP-loaded cells are readily detected by MRI.

Role of Resident Stem Cells in Vessel Formation and Arteriosclerosis.

PubMed

Zhang, Li; Issa Bhaloo, Shirin; Chen, Ting; Zhou, Bin; Xu, Qingbo

2018-05-25

Vascular, resident stem cells are present in all 3 layers of the vessel wall; they play a role in vascular formation under physiological conditions and in remodeling in pathological situations. Throughout development and adult early life, resident stem cells participate in vessel formation through vasculogenesis and angiogenesis. In adults, the vascular stem cells are mostly quiescent in their niches but can be activated in response to injury and participate in endothelial repair and smooth muscle cell accumulation to form neointima. However, delineation of the characteristics and of the migration and differentiation behaviors of these stem cells is an area of ongoing investigation. A set of genetic mouse models for cell lineage tracing has been developed to specifically address the nature of these cells and both migration and differentiation processes during physiological angiogenesis and in vascular diseases. This review summarizes the current knowledge on resident stem cells, which has become more defined and refined in vascular biology research, thus contributing to the development of new potential therapeutic strategies to promote endothelial regeneration and ameliorate vascular disease development. © 2018 The Authors.

A systematic review on the role of environmental toxicants in stem cells aging.

PubMed

Hodjat, Mahshid; Rezvanfar, Mohammad Amin; Abdollahi, Mohammad

2015-12-01

Stem cells are an important target for environmental toxicants. As they are the main source for replenishing of organs in the body, any changes in their normal function could affect the regenerative potential of organs, leading to the appearance of age-related disease and acceleration of the aging process. Environmental toxicants could exert their adverse effect on stem cell function via multiple cellular and molecular mechanisms, resulting in changes in the stem cell differentiation fate and cell transformation, and reduced self-renewal capacity, as well as induction of stress-induced cellular senescence. The present review focuses on the effect of environmental toxicants on stem cell function associated with the aging process. We categorized environmental toxicants according to their preferred molecular mechanism of action on stem cells, including changes in genomic, epigenomic, and proteomic levels and enhancing oxidative stress. Pesticides, tobacco smoke, radiation and heavy metals are well-studied toxicants that cause stem cell dysfunction via induction of oxidative stress. Transgenerational epigenetic changes are the most important effects of a variety of toxicants on germ cells and embryos that are heritable and could affect health in the next several generations. A better understanding of the underlying mechanisms of toxicant-induced stem cell aging will help us to develop therapeutic intervention strategies against environmental aging. Meanwhile, more efforts are required to find the direct in vivo relationship between adverse effect of environmental toxicants and stem cell aging, leading to organismal aging. Copyright © 2015 Elsevier Ltd. All rights reserved.

Allogenic banking of dental pulp stem cells for innovative therapeutics.

PubMed

Collart-Dutilleul, Pierre-Yves; Chaubron, Franck; De Vos, John; Cuisinier, Frédéric J

2015-08-26

Medical research in regenerative medicine and cell-based therapy has brought encouraging perspectives for the use of stem cells in clinical trials. Multiple types of stem cells, from progenitors to pluripotent stem cells, have been investigated. Among these, dental pulp stem cells (DPSCs) are mesenchymal multipotent cells coming from the dental pulp, which is the soft tissue within teeth. They represent an interesting adult stem cell source because they are recovered in large amount in dental pulps with non-invasive techniques compared to other adult stem cell sources. DPSCs can be obtained from discarded teeth, especially wisdom teeth extracted for orthodontic reasons. To shift from promising preclinical results to therapeutic applications to human, DPSCs must be prepared in clinical grade lots and transformed into advanced therapy medicinal products (ATMP). As the production of patient-specific stem cells is costly and time-consuming, allogenic biobanking of clinical grade human leukocyte antigen (HLA)-typed DPSC lines provides efficient innovative therapeutic products. DPSC biobanks represent industrial and therapeutic innovations by using discarded biological tissues (dental pulps) as a source of mesenchymal stem cells to produce and store, in good manufacturing practice (GMP) conditions, DPSC therapeutic batches. In this review, we discuss about the challenges to transfer biological samples from a donor to HLA-typed DPSC therapeutic lots, following regulations, GMP guidelines and ethical principles. We also present some clinical applications, for which there is no efficient therapeutics so far, but that DPSCs-based ATMP could potentially treat.

Allogenic banking of dental pulp stem cells for innovative therapeutics

PubMed Central

Collart-Dutilleul, Pierre-Yves; Chaubron, Franck; De Vos, John; Cuisinier, Frédéric J

2015-01-01

Medical research in regenerative medicine and cell-based therapy has brought encouraging perspectives for the use of stem cells in clinical trials. Multiple types of stem cells, from progenitors to pluripotent stem cells, have been investigated. Among these, dental pulp stem cells (DPSCs) are mesenchymal multipotent cells coming from the dental pulp, which is the soft tissue within teeth. They represent an interesting adult stem cell source because they are recovered in large amount in dental pulps with non-invasive techniques compared to other adult stem cell sources. DPSCs can be obtained from discarded teeth, especially wisdom teeth extracted for orthodontic reasons. To shift from promising preclinical results to therapeutic applications to human, DPSCs must be prepared in clinical grade lots and transformed into advanced therapy medicinal products (ATMP). As the production of patient-specific stem cells is costly and time-consuming, allogenic biobanking of clinical grade human leukocyte antigen (HLA)-typed DPSC lines provides efficient innovative therapeutic products. DPSC biobanks represent industrial and therapeutic innovations by using discarded biological tissues (dental pulps) as a source of mesenchymal stem cells to produce and store, in good manufacturing practice (GMP) conditions, DPSC therapeutic batches. In this review, we discuss about the challenges to transfer biological samples from a donor to HLA-typed DPSC therapeutic lots, following regulations, GMP guidelines and ethical principles. We also present some clinical applications, for which there is no efficient therapeutics so far, but that DPSCs-based ATMP could potentially treat. PMID:26328017

Prolonged Growth Hormone/Insulin/Insulin-like Growth Factor Nutrient Response Signaling Pathway as a Silent Killer of Stem Cells and a Culprit in Aging.

PubMed

Ratajczak, Mariusz Z; Bartke, Andrzej; Darzynkiewicz, Zbigniew

2017-08-01

The dream of slowing down the aging process has always inspired mankind. Since stem cells are responsible for tissue and organ rejuvenation, it is logical that we should search for encoded mechanisms affecting life span in these cells. However, in adult life the hierarchy within the stem cell compartment is still not very well defined, and evidence has accumulated that adult tissues contain rare stem cells that possess a broad trans-germ layer differentiation potential. These most-primitive stem cells-those endowed with pluripotent or multipotent differentiation ability and that give rise to other cells more restricted in differentiation, known as tissue-committed stem cells (TCSCs) - are of particular interest. In this review we present the concept supported by accumulating evidence that a population of so-called very small embryonic-like stem cells (VSELs) residing in adult tissues positively impacts the overall survival of mammals, including humans. These unique cells are prevented in vertebrates from premature depletion by decreased sensitivity to growth hormone (GH), insulin (INS), and insulin-like growth factor (IGF) signaling, due to epigenetic changes in paternally imprinted genes that regulate their resistance to these factors. In this context, we can envision nutrient response GH/INS/IGF signaling pathway as a lethal factor for these most primitive stem cells and an important culprit in aging.

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

PubMed

Lescaudron, L; Naveilhan, P; Neveu, I

2012-01-01

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

Separation technologies for stem cell bioprocessing.

PubMed

Diogo, Maria Margarida; da Silva, Cláudia Lobato; Cabral, Joaquim M S

2012-11-01

Stem cells have been the focus of an intense research due to their potential in Regenerative Medicine, drug discovery, toxicology studies, as well as for fundamental studies on developmental biology and human disease mechanisms. To fully accomplish this potential, the successful application of separation processes for the isolation and purification of stem cells and stem cell-derived cells is a crucial issue. Although separation methods have been used over the past decades for the isolation and enrichment of hematopoietic stem/progenitor cells for transplantation in hemato-oncological settings, recent achievements in the stem cell field have created new challenges including the need for novel scalable separation processes with a higher resolution and more cost-effective. Important examples are the need for high-resolution methods for the separation of heterogeneous populations of multipotent adult stem cells to study their differential biological features and clinical utility, as well as for the depletion of tumorigenic cells after pluripotent stem cell differentiation. Focusing on these challenges, this review presents a critical assessment of separation processes that have been used in the stem cell field, as well as their current and potential applications. The techniques are grouped according to the fundamental principles that govern cell separation, which are defined by the main physical, biophysical, and affinity properties of cells. A special emphasis is given to novel and promising approaches such as affinity-based methods that take advantage of the use of new ligands (e.g., aptamers, lectins), as well as to novel biophysical-based methods requiring no cell labeling and integrated with microscale technologies. Copyright © 2012 Wiley Periodicals, Inc.

Chapter 17 Sterile Plate-Based Vitrification of Adherent Human Pluripotent Stem Cells and Their Derivatives Using the TWIST Method.

PubMed

Neubauer, Julia C; Stracke, Frank; Zimmermann, Heiko

2017-01-01

Due to their high biological complexity, e.g., their close cell-to-cell contacts, cryopreservation of human pluripotent stem cells with standard slow-rate protocols often is inefficient and can hardly be standardized. Vitrification that means ultrafast freezing already showed very good viability and recovery rates for this sensitive cell system, but is only applicable for low cell numbers, bears a high risk of contamination, and can hardly be implemented under GxP regulations. In this chapter, a sterile plate-based vitrification method for adherent pluripotent stem cells and their derivatives is presented based on a procedure and device for human embryonic stem cells developed by Beier et al. (Cryobiology 66:8-16, 2013). This protocol overcomes the limitations of conventional vitrification procedures resulting in the highly efficient preservation of ready-to-use adherent pluripotent stem cells with the possibility of vitrifying cells in multi-well formats for direct application in high-throughput screenings.

The effect of Bcr-Abl protein tyrosine kinase on maturation and proliferation of primitive haematopoietic cells.

PubMed Central

Buckle, A. M.; Mottram, R.; Pierce, A.; Lucas, G. S.; Russell, N.; Miyan, J. A.; Whetton, A. D.

2000-01-01

BACKGROUND: Chronic Myeloid Leukaemia (CML) is characterised by the chromosomal translocation resulting in expression of the Bcr-Abl protein tyrosine kinase (PTK) in early stem cells and their progeny. However the precise nature of Bcr-Abl effects in primitive CML stem cells remains a matter of active debate. MATERIALS AND METHODS: Extremely primitive Bcr-Abl fusion positive cells were purified from patients with CML using multiparameter flow cytometric analysis of CD34, Thy, and lineage marker (Lin) expression, plus rhodamine-123 (Rh-123) brightness. Progenitor cells of increasing maturity were examined for cycling status by flow cytometry and their proliferative status directly correlated with cell phenotype. The activation status of a key transcription factor, signal transducers and activators of transcription (STAT-5), was also analyzed by immunocytochemistry. RESULTS: The most primitive stem cells currently defined (CD34+Lin-Thy+ Rh-1231o) were present as a lower proportion of the stem cell compartment (CD34+Lin-) of CML patients at presentation than of normal individuals (2.3% +/- 0.4 compared with 5.1% +/- 0.6 respectively). Conversely there was a significantly higher proportion of the more mature cells (CD34+Lin-Thy-Rh-123 hi) in CML patients than in normal individuals (79.3 +/- 1.8 compared with 70.9 +/- 3.3). No primitive subpopulation of CML CD34+Lin- cells was cycling to a significantly greater degree than cells from normal donors, in fact, late progenitor cells (CD34+Lin+) were cycling significantly less in CML samples than normal samples. STAT5, however, was observed to be activated in CML cells. CONCLUSIONS: We conclude that no subpopulation of CML stem cells displays significantly increased cell cycling. Thus, increased cycling cannot be a direct consequence of Bcr-Abl PTK acquisition in highly enriched stem cells from patients with CML. In vivo CML need not be considered a disease of unbridled stem cell proliferation, but a subtle defect in the balance between self renewal and maturation. PMID:11126203

Maintenance of neural progenitor cell stemness in 3D hydrogels requires matrix remodelling

NASA Astrophysics Data System (ADS)

Madl, Christopher M.; Lesavage, Bauer L.; Dewi, Ruby E.; Dinh, Cong B.; Stowers, Ryan S.; Khariton, Margarita; Lampe, Kyle J.; Nguyen, Duong; Chaudhuri, Ovijit; Enejder, Annika; Heilshorn, Sarah C.

2017-12-01

Neural progenitor cell (NPC) culture within three-dimensional (3D) hydrogels is an attractive strategy for expanding a therapeutically relevant number of stem cells. However, relatively little is known about how 3D material properties such as stiffness and degradability affect the maintenance of NPC stemness in the absence of differentiation factors. Over a physiologically relevant range of stiffness from ~0.5 to 50 kPa, stemness maintenance did not correlate with initial hydrogel stiffness. In contrast, hydrogel degradation was both correlated with, and necessary for, maintenance of NPC stemness. This requirement for degradation was independent of cytoskeletal tension generation and presentation of engineered adhesive ligands, instead relying on matrix remodelling to facilitate cadherin-mediated cell-cell contact and promote β-catenin signalling. In two additional hydrogel systems, permitting NPC-mediated matrix remodelling proved to be a generalizable strategy for stemness maintenance in 3D. Our findings have identified matrix remodelling, in the absence of cytoskeletal tension generation, as a previously unknown strategy to maintain stemness in 3D.

Maintenance of Neural Progenitor Cell Stemness in 3D Hydrogels Requires Matrix Remodeling

PubMed Central

Madl, Christopher M.; LeSavage, Bauer L.; Dewi, Ruby E.; Dinh, Cong B.; Stowers, Ryan S.; Khariton, Margarita; Lampe, Kyle J.; Nguyen, Duong; Chaudhuri, Ovijit; Enejder, Annika; Heilshorn, Sarah C.

2017-01-01

Neural progenitor cell (NPC) culture within 3D hydrogels is an attractive strategy for expanding a therapeutically-relevant number of stem cells. However, relatively little is known about how 3D material properties such as stiffness and degradability affect the maintenance of NPC stemness in the absence of differentiation factors. Over a physiologically-relevant range of stiffness from ~0.5–50 kPa, stemness maintenance did not correlate with initial hydrogel stiffness. In contrast, hydrogel degradation was both correlated with, and necessary for, maintenance of NPC stemness. This requirement for degradation was independent of cytoskeletal tension generation and presentation of engineered adhesive ligands, instead relying on matrix remodeling to facilitate cadherin-mediated cell-cell contact and promote β-catenin signaling. In two additional hydrogel systems, permitting NPC-mediated matrix remodeling proved to be a generalizable strategy for stemness maintenance in 3D. Our findings have identified matrix remodeling, in the absence of cytoskeletal tension generation, as a previously unknown strategy to maintain stemness in 3D. PMID:29115291

Femtosecond laser pulses for chemical-free embryonic and mesenchymal stem cell differentiation

NASA Astrophysics Data System (ADS)

Mthunzi, Patience; Dholakia, Kishan; Gunn-Moore, Frank

2011-10-01

Owing to their self renewal and pluripotency properties, stem cells can efficiently advance current therapies in tissue regeneration and/or engineering. Under appropriate culture conditions in vitro, pluripotent stem cells can be primed to differentiate into any cell type some examples including neural, cardiac and blood cells. However, there still remains a pressing necessity to answer the biological questions concerning how stem cell renewal and how differentiation programs are operated and regulated at the genetic level. In stem cell research, an urgent requirement on experimental procedures allowing non-invasive, marker-free observation of growth, proliferation and stability of living stem cells under physiological conditions exists. Femtosecond (fs) laser pulses have been reported to non-invasively deliver exogenous materials, including foreign genetic species into both multipotent and pluripotent stem cells successfully. Through this multi-photon facilitated technique, directly administering fs laser pulses onto the cell plasma membrane induces transient submicrometer holes, thereby promoting cytosolic uptake of the surrounding extracellular matter. To display a chemical-free cell transfection procedure that utilises micro-litre scale volumes of reagents, we report for the first time on 70 % transfection efficiency in ES-E14TG2a cells using the enhanced green fluorescing protein (EGFP) DNA plasmid. We also show how varying the average power output during optical transfection influences cell viability, proliferation and cytotoxicity in embryonic stem cells. The impact of utilizing objective lenses of different numerical aperture (NA) on the optical transfection efficiency in ES-E14TG2a cells is presented. Finally, we report on embryonic and mesenchymal stem cell differentiation. The produced specialized cell types could thereafter be characterized and used for cell based therapies.

Primary brain tumors, neural stem cell, and brain tumor cancer cells: where is the link?

PubMed Central

Germano, Isabelle; Swiss, Victoria; Casaccia, Patrizia

2010-01-01

The discovery of brain tumor-derived cells (BTSC) with the properties of stem cells has led to the formulation of the hypothesis that neural stem cells could be the cell of origin of primary brain tumors (PBT). In this review we present the most common molecular changes in PBT, define the criteria of identification of BTSC and discuss the similarities between the characteristics of these cells and those of the endogenous population of neural stem cells (NPCs) residing in germinal areas of the adult brain. Finally, we propose possible mechanisms of cancer initiation and progression and suggest a model of tumor initiation that includes intrinsic changes of resident NSC and potential changes in the microenvironment defining the niche where the NSC reside. PMID:20045420

Niche matters: The comparison between bone marrow stem cells and endometrial stem cells and stromal fibroblasts reveal distinct migration and cytokine profiles in response to inflammatory stimulus

PubMed Central

Sorjamaa, Anna; Kangasniemi, Marika; Sutinen, Meeri; Salo, Tuula; Liakka, Annikki; Lehenkari, Petri; Tapanainen, Juha S.; Vuolteenaho, Olli; Chen, Joseph C.; Lehtonen, Siri; Piltonen, Terhi T.

2017-01-01

Objective Intrinsic inflammatory characteristics play a pivotal role in stem cell recruitment and homing through migration where the subsequent change in niche has been shown to alter these characteristics. The bone marrow mesenchymal stem cells (bmMSCs) have been demonstrated to migrate to the endometrium contributing to the stem cell reservoir and regeneration of endometrial tissue. Thus, the aim of the present study was to compare the inflammation-driven migration and cytokine secretion profile of human bmMSCs to endometrial mesenchymal stem cells (eMSCs) and endometrial fibroblasts (eSFs). Materials and methods The bmMSCs were isolated from bone marrow aspirates through culturing, whereas eMSCs and eSFs were FACS-isolated. All cell types were tested for their surface marker, proliferation profiles and migration properties towards serum and inflammatory attractants. The cytokine/chemokine secretion profile of 35 targets was analysed in each cell type at basal level along with lipopolysaccharide (LPS)-induced state. Results Both stem cell types, bmMSCs and eMSCs, presented with similar stem cell surface marker profiles as well as possessed high proliferation and migration potential compared to eSFs. In multiplex assays, the secretion of 16 cytokine targets was detected and LPS stimulation expanded the cytokine secretion pattern by triggering the secretion of several targets. The bmMSCs exhibited higher cytokine secretion of vascular endothelial growth factor (VEGF)-A, stromal cell-derived factor-1 alpha (SDF)-1α, interleukin-1 receptor antagonist (IL-1RA), IL-6, interferon-gamma inducible protein (IP)-10, monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)1α and RANTES compared to eMSCs and/or eSFs after stimulation with LPS. The basal IL-8 secretion was higher in both endometrial cell types compared to bmMSCs. Conclusion Our results highlight that similar to bmMSCs, the eMSCs possess high migration activity while the differentiation process towards stromal fibroblasts seemed to result in loss of stem cell surface markers, minimal migration activity and a subtler cytokine profile likely contributing to normal endometrial function. PMID:28419140

The novel AML stem cell associated antigen CLL-1 aids in discrimination between normal and leukemic stem cells.

PubMed

van Rhenen, Anna; van Dongen, Guus A M S; Kelder, Angèle; Rombouts, Elwin J; Feller, Nicole; Moshaver, Bijan; Stigter-van Walsum, Marijke; Zweegman, Sonja; Ossenkoppele, Gert J; Jan Schuurhuis, Gerrit

2007-10-01

In CD34(+) acute myeloid leukemia (AML), the malignant stem cells reside in the CD38(-) compartment. We have shown before that the frequency of such CD34(+)CD38(-) cells at diagnosis correlates with minimal residual disease (MRD) frequency after chemotherapy and with survival. Specific targeting of CD34(+)CD38(-) cells might thus offer therapeutic options. Previously, we found that C-type lectin-like molecule-1 (CLL-1) has high expression on the whole blast compartment in the majority of AML cases. We now show that CLL-1 expression is also present on the CD34(+)CD38(-) stem- cell compartment in AML (77/89 patients). The CD34(+)CLL-1(+) population, containing the CD34(+)CD38(-)CLL-1(+) cells, does engraft in nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice with outgrowth to CLL-1(+) blasts. CLL-1 expression was not different between diagnosis and relapse (n = 9). In remission, both CLL-1(-) normal and CLL-1(+) malignant CD34(+)CD38(-) cells were present. A high CLL-1(+) fraction was associated with quick relapse. CLL-1 expression is completely absent both on CD34(+)CD38(-) cells in normal (n = 11) and in regenerating bone marrow controls (n = 6). This AML stem-cell specificity of the anti-CLL-1 antibody under all conditions of disease and the leukemia-initiating properties of CD34(+)CLL-1(+) cells indicate that anti-CLL-1 antibody enables both AML-specific stem-cell detection and possibly antigen-targeting in future.

Concise Review: Fabrication, Customization, and Application of Cell Mimicking Microparticles in Stem Cell Science

PubMed Central

Labriola, Nicholas R.; Azagury, Aharon; Gutierrez, Robert; Mathiowitz, Edith

2018-01-01

Abstract Stem and non‐stem cell behavior is heavily influenced by the surrounding microenvironment, which includes other cells, matrix, and potentially biomaterials. Researchers have been successful in developing scaffolds and encapsulation techniques to provide stem cells with mechanical, topographical, and chemical cues to selectively direct them toward a desired differentiation pathway. However, most of these systems fail to present truly physiological replications of the in vivo microenvironments that stem cells are typically exposed to in tissues. Thus, cell mimicking microparticles (CMMPs) have been developed to more accurately recapitulate the properties of surrounding cells while still offering ways to tailor what stimuli are presented. This nascent field holds the promise of reducing, or even eliminating, the need for live cells in select, regenerative medicine therapies, and diagnostic applications. Recent, CMMP‐based studies show great promise for the technology, yet only reproduce a small subset of cellular characteristics from among those possible: size, morphology, topography, mechanical properties, surface molecules, and tailored chemical release to name the most prominent. This Review summarizes the strengths, weaknesses, and ideal applications of micro/nanoparticle fabrication and customization methods relevant to cell mimicking and provides an outlook on the future of this technology. Moving forward, researchers should seek to combine multiple techniques to yield CMMPs that replicate as many cellular characteristics as possible, with an emphasis on those that most strongly influence the desired therapeutic effects. The level of flexibility in customizing CMMP properties allows them to substitute for cells in a variety of regenerative medicine, drug delivery, and diagnostic systems. Stem Cells Translational Medicine 2018;7:232–240 PMID:29316362

Neural Stem Cells Derived Directly from Adipose Tissue.

PubMed

Petersen, Eric D; Zenchak, Jessica R; Lossia, Olivia V; Hochgeschwender, Ute

2018-05-01

Neural stem cells (NSCs) are characterized as self-renewing cell populations with the ability to differentiate into the multiple tissue types of the central nervous system. These cells can differentiate into mature neurons, astrocytes, and oligodendrocytes. This category of stem cells has been shown to be a promisingly effective treatment for neurodegenerative diseases and neuronal injury. Most treatment studies with NSCs in animal models use embryonic brain-derived NSCs. This approach presents both ethical and feasibility issues for translation to human patients. Adult tissue is a more practical source of stem cells for transplantation therapies in humans. Some adult tissues such as adipose tissue and bone marrow contain a wide variety of stem cell populations, some of which have been shown to be similar to embryonic stem cells, possessing many pluripotent properties. Of these stem cell populations, some are able to respond to neuronal growth factors and can be expanded in vitro, forming neurospheres analogous to cells harvested from embryonic brain tissue. In this study, we describe a method for the collection and culture of cells from adipose tissue that directly, without going through intermediates such as mesenchymal stem cells, results in a population of NSCs that are able to be expanded in vitro and be differentiated into functional neuronal cells. These adipose-derived NSCs display a similar phenotype to those directly derived from embryonic brain. When differentiated into neurons, cells derived from adipose tissue have spontaneous spiking activity with network characteristics similar to that of neuronal cultures.

Boron neutron capture therapy induces cell cycle arrest and cell apoptosis of glioma stem/progenitor cells in vitro.

PubMed

Sun, Ting; Zhang, Zizhu; Li, Bin; Chen, Guilin; Xie, Xueshun; Wei, Yongxin; Wu, Jie; Zhou, Youxin; Du, Ziwei

2013-08-06

Glioma stem cells in the quiescent state are resistant to clinical radiation therapy. An almost inevitable glioma recurrence is due to the persistence of these cells. The high linear energy transfer associated with boron neutron capture therapy (BNCT) could kill quiescent and proliferative cells. The present study aimed to evaluate the effects of BNCT on glioma stem/progenitor cells in vitro. The damage induced by BNCT was assessed using cell cycle progression, apoptotic cell ratio and apoptosis-associated proteins expression. The surviving fraction and cell viability of glioma stem/progenitor cells were decreased compared with differentiated glioma cells using the same boronophenylalanine pretreatment and the same dose of neutron flux. BNCT induced cell cycle arrest in the G2/M phase and cell apoptosis via the mitochondrial pathway, with changes in the expression of associated proteins. Glioma stem/progenitor cells, which are resistant to current clinical radiotherapy, could be effectively killed by BNCT in vitro via cell cycle arrest and apoptosis using a prolonged neutron irradiation, although radiosensitivity of glioma stem/progenitor cells was decreased compared with differentiated glioma cells when using the same dose of thermal neutron exposure and boronophenylalanine pretreatment. Thus, BNCT could offer an appreciable therapeutic advantage to prevent tumor recurrence, and may become a promising treatment in recurrent glioma.

Nanotechniques Inactivate Cancer Stem Cells

NASA Astrophysics Data System (ADS)

Goltsev, Anatoliy N.; Babenko, Natalya N.; Gaevskaya, Yulia A.; Bondarovich, Nikolay A.; Dubrava, Tatiana G.; Ostankov, Maksim V.; Chelombitko, Olga V.; Malyukin, Yuriy V.; Klochkov, Vladimir K.; Kavok, Nataliya S.

2017-06-01

One of the tasks of current oncology is identification of cancer stem cells and search of therapeutic means capable of their specific inhibition. The paper presents the data on phenotype characteristics of Ehrlich carcinoma cells as convenient and easy-to-follow model of tumor growth. The evidence of cancer stem cells as a part of Ehrlich carcinoma and significance of CD44+ and CD44- subpopulations in maintaining the growth of this type of tumor were demonstrated. A high (tenfold) tumorigenic activity of the Ehrlich carcinoma CD44+ cells if compared to CD44- cells was proven. In this pair of comparison, the CD44+ cells had a higher potential of generating in peritoneal cavity of CD44high, CD44+CD24-, CD44+CD24+ cell subpopulations, highlighting the presence of cancer stem cells in a pool of CD44+ cells.

Application of platelet-rich plasma with stem cells in bone and periodontal tissue engineering

PubMed Central

Fernandes, Gabriela; Yang, Shuying

2016-01-01

Presently, there is a high paucity of bone grafts in the United States and worldwide. Regenerating bone is of prime concern due to the current demand of bone grafts and the increasing number of diseases causing bone loss. Autogenous bone is the present gold standard of bone regeneration. However, disadvantages like donor site morbidity and its decreased availability limit its use. Even allografts and synthetic grafting materials have their own limitations. As certain specific stem cells can be directed to differentiate into an osteoblastic lineage in the presence of growth factors (GFs), it makes stem cells the ideal agents for bone regeneration. Furthermore, platelet-rich plasma (PRP), which can be easily isolated from whole blood, is often used for bone regeneration, wound healing and bone defect repair. When stem cells are combined with PRP in the presence of GFs, they are able to promote osteogenesis. This review provides in-depth knowledge regarding the use of stem cells and PRP in vitro, in vivo and their application in clinical studies in the future. PMID:28018706

Investigating Cell Surface Markers on Normal Hematopoietic Stem Cells in Three Different Niche Conditions

PubMed Central

Garg, Swati; Madkaikar, Manisha

2013-01-01

Hematopoietic stem cells are of therapeutic interest to the clinicians and researchers due to their promising assistance in management of malignant and inherited hematological conditions. Evaluation of cell surface markers using multiparametric flow cytometry is a well adapted qualitative measure of cells in question for many years. An artillery of these markers has been studied in hematological malignancies and related disorders. However, their role and differential expression on normal hematopoietic stem cells from clinically available sources is not always described carefully. In the present study, we attempted to evaluate expression of CD44, CD90, CD96 and CD123 in three clinically available sources of normal HSCs (Hematopoietic stem cells). Sources of HSCs in the present study involved umbilical cord blood (UCB), normal bone marrow (NBM) and bone marrow from idiopathic thrombocytopenic purpura (ITP) patients (IBM). CD44 is an important homing receptor while CD90 is involved in maintaining stem cell quiescent. CD96 is known to be leukemia specific marker and CD123 is involved in stem cell differentiation and survival. We observed a significant difference in expression CD44, CD90 and CD123 on normal HSCs derived from umbilical cord and ITP marrow. CD96 was highly expressed on HSCs obtained from ITP marrow. Investigating expression of these markers on normal HSCs in different niches will be helpful in correlating their function with niche condition and delineating their ‘abnormal’ expression from the normal. PMID:24386557

Investigating cell surface markers on normal hematopoietic stem cells in three different niche conditions.

PubMed

Garg, Swati; Madkaikar, Manisha; Ghosh, Kanjaksha

2013-11-01

Hematopoietic stem cells are of therapeutic interest to the clinicians and researchers due to their promising assistance in management of malignant and inherited hematological conditions. Evaluation of cell surface markers using multiparametric flow cytometry is a well adapted qualitative measure of cells in question for many years. An artillery of these markers has been studied in hematological malignancies and related disorders. However, their role and differential expression on normal hematopoietic stem cells from clinically available sources is not always described carefully. In the present study, we attempted to evaluate expression of CD44, CD90, CD96 and CD123 in three clinically available sources of normal HSCs (Hematopoietic stem cells). Sources of HSCs in the present study involved umbilical cord blood (UCB), normal bone marrow (NBM) and bone marrow from idiopathic thrombocytopenic purpura (ITP) patients (IBM). CD44 is an important homing receptor while CD90 is involved in maintaining stem cell quiescent. CD96 is known to be leukemia specific marker and CD123 is involved in stem cell differentiation and survival. We observed a significant difference in expression CD44, CD90 and CD123 on normal HSCs derived from umbilical cord and ITP marrow. CD96 was highly expressed on HSCs obtained from ITP marrow. Investigating expression of these markers on normal HSCs in different niches will be helpful in correlating their function with niche condition and delineating their 'abnormal' expression from the normal.

Transplant of Hepatocytes, Undifferentiated Mesenchymal Stem Cells, and In Vitro Hepatocyte-Differentiated Mesenchymal Stem Cells in a Chronic Liver Failure Experimental Model: A Comparative Study.

PubMed

El Baz, Hanan; Demerdash, Zeinab; Kamel, Manal; Atta, Shimaa; Salah, Faten; Hassan, Salwa; Hammam, Olfat; Khalil, Heba; Meshaal, Safa; Raafat, Inas

2018-02-01

Liver transplant is the cornerstone line of treatment for chronic liver diseases; however, the long list of complications and obstacles stand against this operation. Searching for new modalities for treatment of chronic liver illness is a must. In the present research, we aimed to compare the effects of transplant of undifferentiated human mesenchymal stem cells, in vitro differentiated mesenchymal stem cells, and adult hepatocytes in an experimental model of chronic liver failure. Undifferentiated human cord blood mesenchymal stem cells were isolated, pro-pagated, and characterized by morphology, gene expression analysis, and flow cytometry of surface markers and in vitro differentiated into hepatocyte-like cells. Rat hepatocytes were isolated by double perfusion technique. An animal model of chronic liver failure was developed, and undifferentiated human cord blood mesenchymal stem cells, in vitro hepato-genically differentiated mesenchymal stem cells, or freshly isolated rat hepatocytes were transplanted into a CCL4 cirrhotic experimental model. Animals were killed 3 months after transplant, and liver functions and histopathology were assessed. Compared with the cirrhotic control group, the 3 cell-treated groups showed improved alanine aminotransferase, aspartate aminotransferase, albumin, and bilirubin levels, with best results shown in the hepatocyte-treated group. Histopathologic examination of the treated groups showed improved fibrosis, with best results obtained in the undifferentiated mesenchymal stem cell-treated group. Both adult hepatocytes and cord blood mesenchymal stem cells proved to be promising candidates for cell-based therapy in liver regeneration on an experimental level. Improved liver function was evident in the hepatocyte-treated group, and fibrosis control was more evident in the undifferentiated mesenchymal stem cell-treated group.

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

PubMed

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

2018-01-01

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

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

PubMed Central

Ratajczak, Jessica; Gervois, Pascal; Clegg, Peter; Bronckaers, Annelies; Vandeweerd, Jean-Michel; Lambrichts, Ivo

2018-01-01

Due to the restricted intrinsic capacity of resident chondrocytes to regenerate the lost cartilage postinjury, stem cell-based therapies have been proposed as a novel therapeutic approach for cartilage repair. Moreover, stem cell-based therapies using mesenchymal stem cells (MSCs) or induced pluripotent stem cells (iPSCs) have been used successfully in preclinical and clinical settings. Despite these promising reports, the exact mechanisms underlying stem cell-mediated cartilage repair remain uncertain. Stem cells can contribute to cartilage repair via chondrogenic differentiation, via immunomodulation, or by the production of paracrine factors and extracellular vesicles. But before novel cell-based therapies for cartilage repair can be introduced into the clinic, rigorous testing in preclinical animal models is required. Preclinical models used in regenerative cartilage studies include murine, lapine, caprine, ovine, porcine, canine, and equine models, each associated with its specific advantages and limitations. This review presents a summary of recent in vitro data and from in vivo preclinical studies justifying the use of MSCs and iPSCs in cartilage tissue engineering. Moreover, the advantages and disadvantages of utilizing small and large animals will be discussed, while also describing suitable outcome measures for evaluating cartilage repair. PMID:29535784

CXCR4/CXCL12 signaling impacts enamel progenitor cell proliferation and motility in the dental stem cell niche

PubMed Central

Otsu, Keishi; Harada, Hidemitsu; Shibata, Shunichi; Obara, Nobuko; Irie, Kazuharu; Taniguchi, Akiyoshi; Nagasawa, Takashi; Aoki, Kazunari; Caliari, Steven R.; Weisgerber, Daniel W.

2015-01-01

Dental stem cells are located at the proximal ends of rodent incisors. These stem cells reside in the dental epithelial stem cell niche, termed the apical bud. We focused on identifying critical features of a chemotactic signal in the niche. Here, we report that CXCR4/CXCL12 signaling impacts enamel progenitor cell proliferation and motility in dental stem cell niche cells. We report cells in the apical bud express CXCR4 mRNA at high levels while expression is restricted in the basal epithelium (BE) and transit-amplifying (TA) cell regions. Furthermore, the CXCL12 ligand is present in mesenchymal cells adjacent to the apical bud. We then performed gain- and loss-of-function analyses to better elucidate the role of CXCR4 and CXCL12. CXCR4-deficient mice contain epithelial cell aggregates, while cell proliferation in mutant incisors was also significantly reduced. We demonstrate in vitro that dental epithelial cells migrate toward sources of CXCL12, whereas knocking down CXCR4 impaired motility and resulted in formation of dense cell colonies. These results suggest that CXCR4 expression may be critical for activation of enamel progenitor cell division and that CXCR4/CXCL12 signaling may control movement of epithelial progenitors from the dental stem cell niche. PMID:26246398

Epigenetics in cancer stem cells.

PubMed

Toh, Tan Boon; Lim, Jhin Jieh; Chow, Edward Kai-Hua

2017-02-01

Compelling evidence have demonstrated that bulk tumors can arise from a unique subset of cells commonly termed "cancer stem cells" that has been proposed to be a strong driving force of tumorigenesis and a key mechanism of therapeutic resistance. Recent advances in epigenomics have illuminated key mechanisms by which epigenetic regulation contribute to cancer progression. In this review, we present a discussion of how deregulation of various epigenetic pathways can contribute to cancer initiation and tumorigenesis, particularly with respect to maintenance and survival of cancer stem cells. This information, together with several promising clinical and preclinical trials of epigenetic modulating drugs, offer new possibilities for targeting cancer stem cells as well as improving cancer therapy overall.

Micro- and nanoengineering for stem cell biology: the promise with a caution.

PubMed

Kshitiz; Kim, Deok-Ho; Beebe, David J; Levchenko, Andre

2011-08-01

Current techniques used in stem cell research only crudely mimic the physiological complexity of the stem cell niches. Recent advances in the field of micro- and nanoengineering have brought an array of in vitro cell culture models that have enabled development of novel, highly precise and standardized tools that capture physiological details in a single platform, with greater control, consistency, and throughput. In this review, we describe the micro- and nanotechnology-driven modern toolkit for stem cell biologists to design novel experiments in more physiological microenvironments with increased precision and standardization, and caution them against potential challenges that the modern technologies might present. Copyright © 2011 Elsevier Ltd. All rights reserved.

Taking a Broader View

ERIC Educational Resources Information Center

Flannery, Maura C.

2005-01-01

A study on stem cells is presented by understanding the environment in which they are found, the support cells and blood vessels as well as the protein scaffolds and other molecules. Researchers found that stem cells in reproductive tissue are surrounded by a pocket of support cells that hold them in place and align them to divide properly, so…

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

PubMed

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

2015-06-01

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

Editorial: Our top 10 developments in stem cell biology over the last 30 years.

PubMed

Armstrong, Lyle; Lako, Majlinda; Buckley, Noel; Lappin, Terry R J; Murphy, Martin J; Nolta, Jan A; Pittenger, Mark; Stojkovic, Miodrag

2012-01-01

To celebrate 30 years of peer-reviewed publication of cutting edge stem cell research in Stem Cells, the first journal devoted to this promising field, we pause to review how far we have come in the three-decade lifetime of the Journal. To do this, we will present our views of the 10 most significant developments that have advanced stem cell biology where it is today. With the increasing rate of new data, it is natural that the bulk of these developments would have occurred in recent years, but we must not think that stem cell biology is a young science. The idea of a stem cell has actually been around for quite a long time having appeared in the scientific literature as early as 1868 with Haeckels' concept of a stamzelle as an uncommitted or undifferentiated cell responsible for producing many types of new cells to repair the body [Naturliche Schopfungsgeschichte, 1868; Berlin: Georg Reimer] but it took many years to obtain hard evidence in support of this theory. Not until the work of James Till and Ernest McCulloch in the 1960s did we have proof of the existence of stem cells and until the derivation of embryonal carcinoma cells in the 1960s-1970s and the first embryonic stem cell in 1981, such adult or tissue-specific stem cells were the only known class. The first issue of Stem Cells was published in 1981; no small wonder that most of its papers were devoted to hematopoietic progenitors. More recently, induced pluripotent stem cells (iPSCs) have been developed, and this is proving to be a fertile area of investigation as shown by the volume of publications appearing not only in Stem Cells but also in other journals over the last 5 years. The reader will note that many of the articles in this special issue are concerned with iPSC; however, this reflects the current surge of interest in the topic rather than any deliberate attempt to ignore other areas of stem cell investigation. Copyright © 2011 AlphaMed Press.

Network-based expression analyses and experimental validations revealed high co-expression between Yap1 and stem cell markers compared to differentiated cells.

PubMed

Dehghanian, Fariba; Hojati, Zohreh; Esmaeili, Fariba; Masoudi-Nejad, Ali

2018-05-21

The Hippo signaling pathway is identified as a potential regulatory pathway which plays critical roles in differentiation and stem cell self-renewal. Yap1 is a primary transcriptional effector of this pathway. The importance of Yap1 in embryonic stem cells (ESCs) and differentiation procedure remains a challenging question, since two different observations have been reported. To answer this question we used co-expression network and differential co-expression analyses followed by experimental validations. Our results indicate that Yap1 is highly co-expressed with stem cell markers in ESCs but not in differentiated cells (DCs). The significant Yap1 down-regulation and also translocation of Yap1 into the cytoplasm during P19 differentiation was also detected. Moreover, our results suggest the E2f7, Lin28a and Dppa4 genes as possible regulatory nuclear factors of Hippo pathway in stem cells. The present findings are actively consistent with studies that suggested Yap1 as an essential factor for stem cell self-renewal. Copyright © 2018 Elsevier Inc. All rights reserved.

Canine Adipose-Derived Stem Cells: Purinergic Characterization and Neurogenic Potential for Therapeutic Applications.

PubMed

Roszek, Katarzyna; Makowska, Noemi; Czarnecka, Joanna; Porowińska, Dorota; Dąbrowski, Marcin; Danielewska, Justyna; Nowak, Wiesław

2017-01-01

The presented results evidence that canine adipose-derived stem cells (ADSCs) represent the premature population of stem cells with great biological potential and properties. ADCS are easy to obtain and culture, able to differentiate into the neurogenic lineage as well as it is easy to control their proliferation rate with nucleotides and nucleosides or analogues. We report that in vitro cultured canine ADSCs response to adenosine- and ATP-mediated stimulation. Differences in canine ADSCs and human mesenchymal stem cells in ecto-nucleotidase activity have been observed. The ecto-nucleotidase activity changes during ADSCs in vitro transdifferentiation into neurogenic lineage are fast and simple to analyze. Therefore, the simple analysis of ecto-enzymes activity allows for verification of the stem cells quality: their stemness or initiation of the differentiation process. The biological potential of the cells isolated from canine fat, as well as the good quality control of this cell culture, make them a promising tool for both experimental and therapeutic usage. J. Cell. Biochem. 118: 58-65, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Comparative evaluation of the isolation and quantification of stem cells derived from dental pulp and periodontal ligament of a permanent tooth and to assess their viability and proliferation on a platelet-rich fibrin scaffold.

PubMed

Khurana, Rohit; Kudva, Praveen Bhasker; Husain, Syed Yawer

2017-01-01

The present study aims to comparatively evaluate the isolation and quantification of stem cells derived from dental pulp and periodontal ligament of a permanent tooth and to assess their viability and proliferation on a platelet-rich fibrin (PRF) scaffold. A total of 15 systemically healthy individuals between the age group of 15-25 years requiring third molar or orthodontic premolar extractions. Teeth were extracted atraumatically and transported to the laboratory. Stem cells were isolated from dental pulp and periodontal ligament. After attaining more than 90% confluency by the 7 th day, these cells were tested for their viability and characterization. Stem cells were also incubated with PRF and viability was assessed on the 7 th day. The mean number of cell for dental pulp stem cells (DPSCs) and periodontal ligament stem cell (PDLSC) was statistically insignificant ( P > 0.05). The mean live cell viability was compared between DPSC (98.07%) and PDLSC (98%). Both DPSC and PDLSC showed a high percentage of expression of CD73 markers, 30.40% and 29.80%, respectively. However, DPSCs and PDLSCs lacked expression of CD34 expressing only 3.47% and 3.53%, respectively. PRF membrane as a scaffold exhibited no cytotoxic effects on DPCS's or PDLSC's. The cell viability of cells cultured with PRF was statistically insignificant ( P > 0.05) when compared to the cells cultured with culture media. The study thus indicates that dental pulp and periodontal ligament are both rich sources of mesenchymal stem cells and can be successfully used for obtaining stem cells. PRF exhibits no cytotoxic effects on the cells and can be used in conjunction with dental stem cells.

NF-κB Participates in the Stem Cell Phenotype of Ovarian Cancer Cells.

PubMed

Gonzalez-Torres, Carolina; Gaytan-Cervantes, Javier; Vazquez-Santillan, Karla; Mandujano-Tinoco, Edna Ayerim; Ceballos-Cancino, Gisela; Garcia-Venzor, Alfredo; Zampedri, Cecilia; Sanchez-Maldonado, Paulina; Mojica-Espinosa, Raul; Jimenez-Hernandez, Luis Enrique; Maldonado, Vilma

2017-05-01

NF-κB is a transcription factor involved in cancer stem cells maintenance of many tumors. Little is known about the specific stem-associated upstream regulators of this pathway in ovarian cancer. The Aim of the study was to analyze the role of the canonical and non-canonical NF-κB pathways in stem cells of ovarian cancer cell lines. Stem cells were isolated using sorting cytometry. Western blot and RT-PCR were used to quantify protein and messenger RNA levels. Loss and gain of function assays were performed using siRNAs and dominant-negative proteins, respectively. NF-κB binding activity was measured with a reporter gene assay. The stem phenotype was estimated with clonogenic assays using soft agar, colony formation, ovospheres formation and in vivo tumorigenicity assays. The CD44+ subpopulation of SKOV3 ovarian cancer cell line presented higher mRNA levels of key stemness genes, an increased tumorigenic capacity and higher expression of the RelA, RelB and IKKα. When the canonical pathway was inhibited by means of a dominant-negative version of IkBα, the stem cell population was reduced, as shown by a reduced CD44+ subpopulation, a decrease in the expression of the stemness genes and a reduction of the stem phenotype. In addition, IKKα, the main upstream non-canonical kinase, was highly expressed in the CSC population. Accordingly, when IKKα was inhibited using shRNAs, the expression of the stemness genes was reduced. This report is the first to show the importance of several elements of both NF-κB pathway in maintaining the ovarian cancer stem cell population. Copyright © 2017 IMSS. Published by Elsevier Inc. All rights reserved.

Stem Cell Therapy for the Inner Ear

PubMed Central

Okano, Takayuki

2012-01-01

In vertebrates, perception of sound, motion, and balance is mediated through mechanosensory hair cells located within the inner ear. In mammals, hair cells are only generated during a short period of embryonic development. As a result, loss of hair cells as a consequence of injury, disease, or genetic mutation, leads to permanent sensory deficits. At present, cochlear implantation is the only option for profound hearing loss. However, outcomes are still variable and even the best implant cannot provide the acuity of a biological ear. The recent emergence of stem cell technology has the potential to open new approaches for hair cell regeneration. The goal of this review is to summarize the current state of inner ear stem cell research from a viewpoint of its clinical application for inner ear disorders to illustrate how complementary studies have the potential to promote and refine stem cell therapies for inner ear diseases. The review initially discusses our current understanding of the genetic pathways that regulate hair cell formation from inner ear progenitors during normal development. Subsequent sections discuss the possible use of endogenous inner ear stem cells to induce repair as well as the initial studies aimed at transplanting stem cells into the ear. PMID:22514095

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.

Multiscale microenvironmental perturbation of pluripotent stem cell fate and self-organization

NASA Astrophysics Data System (ADS)

Tabata, Yoji; Lutolf, Matthias P.

2017-03-01

The combination of microfluidics with engineered three-dimensional (3D) matrices can bring new insights into the fate regulation of stem cells and their self-organization into organoids. Although there has been progress in 3D stem cell culturing, most existing in vitro methodologies do not allow for mimicking of the spatiotemporal heterogeneity of stimuli that drive morphogenetic processes in vivo. To address this, we present a perfusion-free microchip concept for the in vitro 3D perturbation of stem cell fate. Stem cells are encapsulated in a hydrogel compartment that is flanked by open reservoirs for the diffusion-driven generation of biomolecule gradients. Juxtaposing additional compartments bearing supportive cells enables investigating the influence of long range cell-cell communication. We explore the utility of the microchips in manipulating early fate choices and self-organizing characteristics of 3D-cultured mouse embryonic stem cells (mESCs) under neural differentiation conditions and exposure to gradients of leukemia inhibitory factor (LIF). mESCs respond to LIF gradients in a spatially dependent manner. At higher LIF concentrations, multicellular colonies maintain pluripotency in contrast, at lower concentrations, mESCs develop into apicobasally polarized epithelial cysts. This versatile system can help to systematically explore the role of multifactorial microenvironments in promoting self-patterning of various stem cell types.

21 CFR 1271.420 - HCT/Ps offered for import.

Code of Federal Regulations, 2010 CFR

2010-04-01

... recipient for reproductive use. (d) This section does not apply to peripheral blood stem/progenitor cells... peripheral blood stem/progenitor cells may present an unreasonable risk of communicable disease transmission...) REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION HUMAN CELLS, TISSUES...

21 CFR 1271.420 - HCT/Ps offered for import.

Code of Federal Regulations, 2011 CFR

2011-04-01

... recipient for reproductive use. (d) This section does not apply to peripheral blood stem/progenitor cells... peripheral blood stem/progenitor cells may present an unreasonable risk of communicable disease transmission...) REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION HUMAN CELLS, TISSUES...

21 CFR 1271.420 - HCT/Ps offered for import.

Code of Federal Regulations, 2014 CFR

2014-04-01

... recipient for reproductive use. (d) This section does not apply to peripheral blood stem/progenitor cells... peripheral blood stem/progenitor cells may present an unreasonable risk of communicable disease transmission...) REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION HUMAN CELLS, TISSUES...

21 CFR 1271.420 - HCT/Ps offered for import.

Code of Federal Regulations, 2013 CFR

2013-04-01

... recipient for reproductive use. (d) This section does not apply to peripheral blood stem/progenitor cells... peripheral blood stem/progenitor cells may present an unreasonable risk of communicable disease transmission...) REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION HUMAN CELLS, TISSUES...

21 CFR 1271.420 - HCT/Ps offered for import.

Code of Federal Regulations, 2012 CFR

2012-04-01

... recipient for reproductive use. (d) This section does not apply to peripheral blood stem/progenitor cells... peripheral blood stem/progenitor cells may present an unreasonable risk of communicable disease transmission...) REGULATIONS UNDER CERTAIN OTHER ACTS ADMINISTERED BY THE FOOD AND DRUG ADMINISTRATION HUMAN CELLS, TISSUES...

Embryonic Stem Cell-Derived Mesenchymal Stem Cells (MSCs) Have a Superior Neuroprotective Capacity Over Fetal MSCs in the Hypoxic-Ischemic Mouse Brain.

PubMed

Hawkins, Kate E; Corcelli, Michelangelo; Dowding, Kate; Ranzoni, Anna M; Vlahova, Filipa; Hau, Kwan-Leong; Hunjan, Avina; Peebles, Donald; Gressens, Pierre; Hagberg, Henrik; de Coppi, Paolo; Hristova, Mariya; Guillot, Pascale V

2018-05-01

Human mesenchymal stem cells (MSCs) have huge potential for regenerative medicine. In particular, the use of pluripotent stem cell-derived mesenchymal stem cells (PSC-MSCs) overcomes the hurdle of replicative senescence associated with the in vitro expansion of primary cells and has increased therapeutic benefits in comparison to the use of various adult sources of MSCs in a wide range of animal disease models. On the other hand, fetal MSCs exhibit faster growth kinetics and possess longer telomeres and a wider differentiation potential than adult MSCs. Here, for the first time, we compare the therapeutic potential of PSC-MSCs (ES-MSCs from embryonic stem cells) to fetal MSCs (AF-MSCs from the amniotic fluid), demonstrating that ES-MSCs have a superior neuroprotective potential over AF-MSCs in the mouse brain following hypoxia-ischemia. Further, we demonstrate that nuclear factor (NF)-κB-stimulated interleukin (IL)-13 production contributes to an increased in vitro anti-inflammatory potential of ES-MSC-conditioned medium (CM) over AF-MSC-CM, thus suggesting a potential mechanism for this observation. Moreover, we show that induced pluripotent stem cell-derived MSCs (iMSCs) exhibit many similarities to ES-MSCs, including enhanced NF-κB signaling and IL-13 production in comparison to AF-MSCs. Future studies should assess whether iMSCs also exhibit similar neuroprotective potential to ES-MSCs, thus presenting a potential strategy to overcome the ethical issues associated with the use of embryonic stem cells and providing a potential source of cells for autologous use against neonatal hypoxic-ischemic encephalopathy in humans. Stem Cells Translational Medicine 2018;7:439-449. © 2018 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

Alk5-Mediated Transforming Growth Factor β Signaling Acts Upstream of Fibroblast Growth Factor 10 To Regulate the Proliferation and Maintenance of Dental Epithelial Stem Cells▿

PubMed Central

Zhao, Hu; Li, Sha; Han, Dong; Kaartinen, Vesa; Chai, Yang

2011-01-01

Mouse incisors grow continuously throughout life. This growth is supported by the division of dental epithelial stem cells that reside in the cervical loop region. Little is known about the maintenance and regulatory mechanisms of dental epithelial stem cells. In the present study, we investigated how transforming growth factor β (TGF-β) signaling-mediated mesenchymal-epithelial cell interactions control dental epithelial stem cells. We designed two approaches using incisor organ culture and bromodeoxyuridine (BrdU) pulse-chase experiments to identify and evaluate stem cell functions. We show that the loss of the TGF-β type I receptor (Alk5) in the cranial neural crest-derived dental mesenchyme severely affects the proliferation of TA (transit-amplifying) cells and the maintenance of dental epithelial stem cells. Incisors of Wnt1-Cre; Alk5fl/fl mice lost their ability to continue to grow in vitro. The number of BrdU label-retaining cells (LRCs) was dramatically reduced in Alk5 mutant mice. Fgf10, Fgf3, and Fgf9 signals in the dental mesenchyme were downregulated in Wnt1-Cre; Alk5fl/fl incisors. Strikingly, the addition of exogenous fibroblast growth factor 10 (FGF10) into cultured incisors rescued dental epithelial stem cells in Wnt1-Cre; Alk5fl/fl mice. Therefore, we propose that Alk5 functions upstream of Fgf10 to regulate TA cell proliferation and stem cell maintenance and that this signaling mechanism is crucial for stem cell-mediated tooth regeneration. PMID:21402782

Stem Cells and Calcium Signaling

PubMed Central

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

2014-01-01

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

Label-Free, High Resolution, Multi-Modal Light Microscopy for Discrimination of Live Stem Cell Differentiation Status.

PubMed

Zhang, Jing; Moradi, Emilia; Somekh, Michael G; Mather, Melissa L

2018-01-15

A label-free microscopy method for assessing the differentiation status of stem cells is presented with potential application for characterization of therapeutic stem cell populations. The microscopy system is capable of characterizing live cells based on the use of evanescent wave microscopy and quantitative phase contrast (QPC) microscopy. The capability of the microscopy system is demonstrated by studying the differentiation of live immortalised neonatal mouse neural stem cells over a 15 day time course. Metrics extracted from microscope images are assessed and images compared with results from endpoint immuno-staining studies to illustrate the system's performance. Results demonstrate the potential of the microscopy system as a valuable tool for cell biologists to readily identify the differentiation status of unlabelled live cells.

Establishment of mouse embryonic stem cells from isolated blastomeres and whole embryos using three derivation methods

PubMed Central

González, Sheyla; Ibáñez, Elena

2010-01-01

Purpose The aim of the present study is to compare three previously described mouse embryonic stem cell derivation methods to evaluate the influence of culture conditions, number of isolated blastomeres and embryonic stage in the derivation process. Methods Three embryonic stem cell derivation methods: standard, pre-adhesion and defined culture medium method, were compared in the derivation from isolated blastomeres and whole embryos at 4- and 8-cell stages. Results A total of 200 embryonic stem cell lines were obtained with an efficiency ranging from 1.9% to 72%. Conclusions Using either isolated blastomeres or whole embryos, the highest rates of mouse embryonic stem cell establishment were achieved with the defined culture medium method and efficiencies increased as development progressed. Using isolated blastomeres, efficiencies increased in parallel to the proportion of the embryo volume used to start the derivation process. PMID:20862536

The many ways to make a luminal cell and a prostate cancer cell.

PubMed

Strand, Douglas W; Goldstein, Andrew S

2015-12-01

Research in the area of stem/progenitor cells has led to the identification of multiple stem-like cell populations implicated in prostate homeostasis and cancer initiation. Given that there are multiple cells that can regenerate prostatic tissue and give rise to prostate cancer, our focus should shift to defining the signaling mechanisms that drive differentiation and progenitor self-renewal. In this article, we will review the literature, present the evidence and raise important unanswered questions that will help guide the field forward in dissecting critical mechanisms regulating stem-cell differentiation and tumor initiation. © 2015 Society for Endocrinology.

Side population purified from hepatocellular carcinoma cells harbors cancer stem cell-like properties.

PubMed

Chiba, Tetsuhiro; Kita, Kaoru; Zheng, Yun-Wen; Yokosuka, Osamu; Saisho, Hiromitsu; Iwama, Atsushi; Nakauchi, Hiromitsu; Taniguchi, Hideki

2006-07-01

Recent advances in stem cell biology enable us to identify cancer stem cells in solid tumors as well as putative stem cells in normal solid organs. In this study, we applied side population (SP) cell analysis and sorting to established hepatocellular carcinoma (HCC) cell lines to detect subpopulations that function as cancer stem cells and to elucidate their roles in tumorigenesis. Among four cell lines analyzed, SP cells were detected in Huh7 (0.25%) and PLC/PRF/5 cells (0.80%), but not in HepG2 and Huh6 cells. SP cells demonstrated high proliferative potential and anti-apoptotic properties compared with those of non-SP cells. Immunocytochemistry examination showed that SP fractions contain a large number of cells presenting characteristics of both hepatocyte and cholangiocyte lineages. Non-obese diabetic/severe combined immunodeficiency (NOD/SCID) xenograft transplant experiments showed that only 1 x 10(3) SP cells were sufficient for tumor formation, whereas an injection of 1 x 10(6) non-SP cells did not initiate tumors. Re-analysis of SP cell-derived tumors showed that SP cells generated both SP and non-SP cells and tumor-initiating potential was maintained only in SP cells in serial transplantation. Microarray analysis discriminated a differential gene expression profile between SP and non-SP cells, and several so-called "stemness genes" were upregulated in SP cells in HCC cells. In conclusion, we propose that a minority population, detected as SP cells in HCC cells, possess extreme tumorigenic potential and provide heterogeneity to the cancer stem cell system characterized by distinct hierarchy.

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

PubMed

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

2011-10-01

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

Clinical grade adult stem cell banking

PubMed Central

Thirumala, Sreedhar; Goebel, W Scott

2009-01-01

There has been a great deal of scientific interest recently generated by the potential therapeutic applications of adult stem cells in human care but there are several challenges regarding quality and safety in clinical applications and a number of these challenges relate to the processing and banking of these cells ex-vivo. As the number of clinical trials and the variety of adult cells used in regenerative therapy increases, safety remains a primary concern. This has inspired many nations to formulate guidelines and standards for the quality of stem cell collection, processing, testing, banking, packaging and distribution. Clinically applicable cryopreservation and banking of adult stem cells offers unique opportunities to advance the potential uses and widespread implementation of these cells in clinical applications. Most current cryopreservation protocols include animal serum proteins and potentially toxic cryoprotectant additives (CPAs) that prevent direct use of these cells in human therapeutic applications. Long term cryopreservation of adult stem cells under good manufacturing conditions using animal product free solutions is critical to the widespread clinical implementation of ex-vivo adult stem cell therapies. Furthermore, to avoid any potential cryoprotectant related complications, reduced CPA concentrations and efficient post-thaw washing to remove CPA are also desirable. The present review focuses on the current strategies and important aspects of adult stem cell banking for clinical applications. These include current good manufacturing practices (cGMPs), animal protein free freezing solutions, cryoprotectants, freezing & thawing protocols, viability assays, packaging and distribution. The importance and benefits of banking clinical grade adult stem cells are also discussed. PMID:20046678

Assessing stemness and proliferation properties of the newly established colon cancer 'stem' cell line, CSC480 and novel approaches to identify dormant cancer cells.

PubMed

Alowaidi, Faisal; Hashimi, Saeed Mujahid; Alqurashi, Naif; Alhulais, Reem; Ivanovski, Saso; Bellette, Bernadette; Meedenyia, Adrian; Lam, Alfred; Wood, Stephen

2018-06-01

To date two questions that remain unanswered regarding cancer are the following: i) how is it initiated, and ii) what is the role that cancer stem cells (CSCs) play in the disease process? Understanding the biology of CSCs and how they are generated is pivotal for the development of successful treatment regimens. To date, the lack of a representative cell model has prevented the successful identification and eradication of CSCs in vivo. The current methods of CSC identification are dependent on the protocol used to generate these cells, which has introduced variation and made the identification process more complicated. Furthermore, the list of possible markers is increasing in complexity. This is further confounded by the fact that there is insufficient information to determine whether the cells these markers detect are truly self‑renewing stem cells or, instead, progenitor cells. In the present study, we investigated a novel cell line model, CSC480, which can be employed to assess CSC markers and for testing novel therapeutic regimens. CSC480 cells have been revealed to express markers of CSCs such as CD44, ALDH1 and Sox2, that have lower expression in the SW480 cell line. CSC480 cells also expressed higher levels of the cancer resistance marker, ABCG2 and had higher proliferative and growth capacity than SW480 cells. In the present study, we also evaluated a novel approach to identify different cell types present in heterogeneous cancer cell populations according to their proliferative ability using the proliferation marker 5‑ethynyl‑2'‑deoxyuridine (EdU). Furthermore, using EdU, we identified dormant cells with a modified label‑retaining cell (LRC) protocol. Through this novel LRC method, we assessed newly discovered markers of stemness to ascertain their capability to identify quiescent from dividing CSCs. In conclusion, the CSC480 cell line was an important model to be used in unravelling the underlying mechanisms that control fast‑dividing and partially self‑renewing stem cells (SCs) that may give rise to cancer.

Identification and characterization of putative stem cells in the adult pig ovary.

PubMed

Bui, Hong-Thuy; Van Thuan, Nguyen; Kwon, Deug-Nam; Choi, Yun-Jung; Kang, Min-Hee; Han, Jae-Woong; Kim, Teoan; Kim, Jin-Hoi

2014-06-01

Recently, the concept of 'neo-oogenesis' has received increasing attention, since it was shown that adult mammals have a renewable source of eggs. The purpose of this study was to elucidate the origin of these eggs and to confirm whether neo-oogenesis continues throughout life in the ovaries of the adult mammal. Adult female pigs were utilized to isolate, identify and characterize, including their proliferation and differentiation capabilities, putative stem cells (PSCs) from the ovary. PSCs were found to comprise a heterogeneous population based on c-kit expression and cell size, and also express stem and germ cell markers. Analysis of PSC molecular progression during establishment showed that these cells undergo cytoplasmic-to-nuclear translocation of Oct4 in a manner reminiscent of gonadal primordial germ cells (PGCs). Hence, cells with the characteristics of early PGCs are present or are generated in the adult pig ovary. Furthermore, the in vitro establishment of porcine PSCs required the presence of ovarian cell-derived extracellular regulatory factors, which are also likely to direct stem cell niche interactions in vivo. In conclusion, the present work supports a crucial role for c-kit and kit ligand/stem cell factor in stimulating the growth, proliferation and nuclear reprogramming of porcine PSCs, and further suggests that porcine PSCs might be the culture equivalent of early PGCs. © 2014. Published by The Company of Biologists Ltd.

Senescence-associated reprogramming promotes cancer stemness.

PubMed

Milanovic, Maja; Fan, Dorothy N Y; Belenki, Dimitri; Däbritz, J Henry M; Zhao, Zhen; Yu, Yong; Dörr, Jan R; Dimitrova, Lora; Lenze, Dido; Monteiro Barbosa, Ines A; Mendoza-Parra, Marco A; Kanashova, Tamara; Metzner, Marlen; Pardon, Katharina; Reimann, Maurice; Trumpp, Andreas; Dörken, Bernd; Zuber, Johannes; Gronemeyer, Hinrich; Hummel, Michael; Dittmar, Gunnar; Lee, Soyoung; Schmitt, Clemens A

2018-01-04

Cellular senescence is a stress-responsive cell-cycle arrest program that terminates the further expansion of (pre-)malignant cells. Key signalling components of the senescence machinery, such as p16 INK4a , p21 CIP1 and p53, as well as trimethylation of lysine 9 at histone H3 (H3K9me3), also operate as critical regulators of stem-cell functions (which are collectively termed 'stemness'). In cancer cells, a gain of stemness may have profound implications for tumour aggressiveness and clinical outcome. Here we investigated whether chemotherapy-induced senescence could change stem-cell-related properties of malignant cells. Gene expression and functional analyses comparing senescent and non-senescent B-cell lymphomas from Eμ-Myc transgenic mice revealed substantial upregulation of an adult tissue stem-cell signature, activated Wnt signalling, and distinct stem-cell markers in senescence. Using genetically switchable models of senescence targeting H3K9me3 or p53 to mimic spontaneous escape from the arrested condition, we found that cells released from senescence re-entered the cell cycle with strongly enhanced and Wnt-dependent clonogenic growth potential compared to virtually identical populations that had been equally exposed to chemotherapy but had never been senescent. In vivo, these previously senescent cells presented with a much higher tumour initiation potential. Notably, the temporary enforcement of senescence in p53-regulatable models of acute lymphoblastic leukaemia and acute myeloid leukaemia was found to reprogram non-stem bulk leukaemia cells into self-renewing, leukaemia-initiating stem cells. Our data, which are further supported by consistent results in human cancer cell lines and primary samples of human haematological malignancies, reveal that senescence-associated stemness is an unexpected, cell-autonomous feature that exerts its detrimental, highly aggressive growth potential upon escape from cell-cycle blockade, and is enriched in relapse tumours. These findings have profound implications for cancer therapy, and provide new mechanistic insights into the plasticity of cancer cells.

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

PubMed

Siddiqi, Faez; Wolfe, John H

2016-10-01

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

The anti-fibrotic effects of mesenchymal stem cells on irradiated lungs via stimulating endogenous secretion of HGF and PGE2

PubMed Central

Dong, Li-Hua; Jiang, Yi-Yao; Liu, Yong-Jun; Cui, Shuang; Xia, Cheng-Cheng; Qu, Chao; Jiang, Xin; Qu, Ya-Qin; Chang, Peng-Yu; Liu, Feng

2015-01-01

Radiation-induced pulmonary fibrosis is a common disease and has a poor prognosis owing to the progressive breakdown of gas exchange regions in the lung. Recently, a novel strategy of administering mesenchymal stem cells for pulmonary fibrosis has achieved high therapeutic efficacy. In the present study, we attempted to use human adipose tissue-derived mesenchymal stem cells to prevent disease in Sprague-Dawley rats that received semi-thoracic irradiation (15 Gy). To investigate the specific roles of mesenchymal stem cells in ameliorating radiation-induced pulmonary fibrosis, we treated control groups of irradiated rats with human skin fibroblasts or phosphate-buffered saline. After mesenchymal stem cells were infused, host secretions of hepatocyte growth factor (HGF) and prostaglandin E2 (PGE2) were elevated compared with those of the controls. In contrast, tumour necrosis factor-alpha (TNF-α) and transforming growth factor-beta1 (TGF-β1) levels were decreased after infusion of mesenchymal stem cells. Consequently, the architecture of the irradiated lungs was preserved without marked activation of fibroblasts or collagen deposition within the injured sites. Moreover, mesenchymal stem cells were able to prevent the irradiated type II alveolar epithelial cells from undergoing epithelial-mesenchymal transition. Collectively, these data confirmed that mesenchymal stem cells have the potential to limit pulmonary fibrosis after exposure to ionising irradiation. PMID:25736907

[Therapeutic strategies targeting brain tumor stem cells].

PubMed

Toda, Masahiro

2009-07-01

Progress in stem cell research reveals cancer stem cells to be present in a variety of malignant tumors. Since they exhibit resistance to anticancer drugs and radiotherapy, analysis of their properties has been rapidly carried forward as an important target for the treatment of intractable malignancies, including brain tumors. In fact, brain cancer stem cells (BCSCs) have been isolated from brain tumor tissue and brain tumor cell lines by using neural stem cell culture methods and isolation methods for side population (SP) cells, which have high drug-efflux capacity. Although the analysis of the properties of BCSCs is the most important to developing methods in treating BCSCs, the absence of BCSC purification methods should be remedied by taking it up as an important research task in the immediate future. Thus far, there are no effective treatment methods for BCSCs, and several treatment methods have been proposed based on the cell biology characteristics of BCSCs. In this article, I outline potential treatment methods damaging treatment-resistant BCSCs, including immunotherapy which is currently a topic of our research.

Transmembrane protein CD9 is glioblastoma biomarker, relevant for maintenance of glioblastoma stem cells

PubMed Central

Podergajs, Neža; Motaln, Helena; Rajčević, Uroš; Verbovšek, Urška; Koršič, Marjan; Obad, Nina; Espedal, Heidi; Vittori, Miloš; Herold-Mende, Christel; Miletic, Hrvoje; Bjerkvig, Rolf; Turnšek, Tamara Lah

2016-01-01

The cancer stem cell model suggests that glioblastomas contain a subpopulation of stem-like tumor cells that reproduce themselves to sustain tumor growth. Targeting these cells thus represents a novel treatment strategy and therefore more specific markers that characterize glioblastoma stem cells need to be identified. In the present study, we performed transcriptomic analysis of glioblastoma tissues compared to normal brain tissues revealing sensible up-regulation of CD9 gene. CD9 encodes the transmembrane protein tetraspanin which is involved in tumor cell invasion, apoptosis and resistance to chemotherapy. Using the public REMBRANDT database for brain tumors, we confirmed the prognostic value of CD9, whereby a more than two fold up-regulation correlates with shorter patient survival. We validated CD9 gene and protein expression showing selective up-regulation in glioblastoma stem cells isolated from primary biopsies and in primary organotypic glioblastoma spheroids as well as in U87-MG and U373 glioblastoma cell lines. In contrast, no or low CD9 gene expression was observed in normal human astrocytes, normal brain tissue and neural stem cells. CD9 silencing in three CD133+ glioblastoma cell lines (NCH644, NCH421k and NCH660h) led to decreased cell proliferation, survival, invasion, and self-renewal ability, and altered expression of the stem-cell markers CD133, nestin and SOX2. Moreover, CD9-silenced glioblastoma stem cells showed altered activation patterns of the Akt, MapK and Stat3 signaling transducers. Orthotopic xenotransplantation of CD9-silenced glioblastoma stem cells into nude rats promoted prolonged survival. Therefore, CD9 should be further evaluated as a target for glioblastoma treatment. PMID:26573230

System for tracking transplanted limbal epithelial stem cells in the treatment of corneal stem cell deficiency (Conference Presentation)

NASA Astrophysics Data System (ADS)

Boadi, Joseph; Matcher, Stephen; MacNeil, Sheila; Sangwan, Virender S.

2016-04-01

The prevailing hypothesis for the existence and healing of the avascular corneal epithelium is that this layer of cells are continually produced by stem cells in the limbus and transported onto the cornea to mature into corneal epithelium. In the event that the cornea is damaged and the limbal stem cell population is severely reduced, this condition known as Limbal Stem Cell Deficiency and can lead to blindness. There are numerous treatments but most have high long term failure rates. Most treatment methods include the transplantation of limbal stem cells into damaged limbus with hope of repopulating the region and regenerating at healthy corneal epithelium. Optical Coherence Tomography (OCT) is well known for its high resolution in vivo images. A bespoke OCT has been built to investigate the trajectories of these limbal stem cells after transplantation to see whether if they do repopulate the damaged limbus or not. In the experimentation magneto-labelling was used to track the limbal stem cells. For the magneto-labelling a mixture of limbal stem cells and cornea epithelium are cultured with super paramagnetic iron (Fe3O4) nanoparticles (20-30nm in size) for 24hours, to allow for uptake. The cells are then transplanted onto the denuded cornea. The transplanted cell mixture with the encapsulated magnetic nanoparticles is actuated with an external magnetic field 0.08T leading to a phase modulation on the signal. A Phase sensitive Magneto-motive OCT is used to locate the transplanted cells. The location of the cells with embed SPIOs were located both in 2D and 3D.

Influence of the extracellular matrix on endogenous and transplanted stem cells after brain damage

PubMed Central

Roll, Lars; Faissner, Andreas

2014-01-01

The limited regeneration capacity of the adult central nervous system (CNS) requires strategies to improve recovery of patients. In this context, the interaction of endogenous as well as transplanted stem cells with their environment is crucial. An understanding of the molecular mechanisms could help to improve regeneration by targeted manipulation. In the course of reactive gliosis, astrocytes upregulate Glial fibrillary acidic protein (GFAP) and start, in many cases, to proliferate. Beside GFAP, subpopulations of these astroglial cells coexpress neural progenitor markers like Nestin. Although cells express these markers, the proportion of cells that eventually give rise to neurons is limited in many cases in vivo compared to the situation in vitro. In the first section, we present the characteristics of endogenous progenitor-like cells and discuss the differences in their neurogenic potential in vitro and in vivo. As the environment plays an important role for survival, proliferation, migration, and other processes, the second section of the review describes changes in the extracellular matrix (ECM), a complex network that contains numerous signaling molecules. It appears that signals in the damaged CNS lead to an activation and de-differentiation of astrocytes, but do not effectively promote neuronal differentiation of these cells. Factors that influence stem cells during development are upregulated in the damaged brain as part of an environment resembling a stem cell niche. We give a general description of the ECM composition, with focus on stem cell-associated factors like the glycoprotein Tenascin-C (TN-C). Stem cell transplantation is considered as potential treatment strategy. Interaction of transplanted stem cells with the host environment is critical for the outcome of stem cell-based therapies. Possible mechanisms involving the ECM by which transplanted stem cells might improve recovery are discussed in the last section. PMID:25191223

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

NASA Astrophysics Data System (ADS)

Abrahamse, Heidi

2009-09-01

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

Lent-On-Plus Lentiviral vectors for conditional expression in human stem cells.

PubMed

Benabdellah, Karim; Muñoz, Pilar; Cobo, Marién; Gutierrez-Guerrero, Alejandra; Sánchez-Hernández, Sabina; Garcia-Perez, Angélica; Anderson, Per; Carrillo-Gálvez, Ana Belén; Toscano, Miguel G; Martin, Francisco

2016-11-17

Conditional transgene expression in human stem cells has been difficult to achieve due to the low efficiency of existing delivery methods, the strong silencing of the transgenes and the toxicity of the regulators. Most of the existing technologies are based on stem cells clones expressing appropriate levels of tTA or rtTA transactivators (based on the TetR-VP16 chimeras). In the present study, we aim the generation of Tet-On all-in-one lentiviral vectors (LVs) that tightly regulate transgene expression in human stem cells using the original TetR repressor. By using appropriate promoter combinations and shielding the LVs with the Is2 insulator, we have constructed the Lent-On-Plus Tet-On system that achieved efficient transgene regulation in human multipotent and pluripotent stem cells. The generation of inducible stem cell lines with the Lent-ON-Plus LVs did not require selection or cloning, and transgene regulation was maintained after long-term cultured and upon differentiation toward different lineages. To our knowledge, Lent-On-Plus is the first all-in-one vector system that tightly regulates transgene expression in bulk populations of human pluripotent stem cells and its progeny.

Lent-On-Plus Lentiviral vectors for conditional expression in human stem cells

PubMed Central

Benabdellah, Karim; Muñoz, Pilar; Cobo, Marién; Gutierrez-Guerrero, Alejandra; Sánchez-Hernández, Sabina; Garcia-Perez, Angélica; Anderson, Per; Carrillo-Gálvez, Ana Belén; Toscano, Miguel G.; Martin, Francisco

2016-01-01

Conditional transgene expression in human stem cells has been difficult to achieve due to the low efficiency of existing delivery methods, the strong silencing of the transgenes and the toxicity of the regulators. Most of the existing technologies are based on stem cells clones expressing appropriate levels of tTA or rtTA transactivators (based on the TetR-VP16 chimeras). In the present study, we aim the generation of Tet-On all-in-one lentiviral vectors (LVs) that tightly regulate transgene expression in human stem cells using the original TetR repressor. By using appropriate promoter combinations and shielding the LVs with the Is2 insulator, we have constructed the Lent-On-Plus Tet-On system that achieved efficient transgene regulation in human multipotent and pluripotent stem cells. The generation of inducible stem cell lines with the Lent-ON-Plus LVs did not require selection or cloning, and transgene regulation was maintained after long-term cultured and upon differentiation toward different lineages. To our knowledge, Lent-On-Plus is the first all-in-one vector system that tightly regulates transgene expression in bulk populations of human pluripotent stem cells and its progeny. PMID:27853296

Ambivalent journeys of hope: embryonic stem cell therapy in a clinic in India.

PubMed

Prasad, Amit

2015-03-01

Stem cell therapy in non-Western countries such as India has received a lot of attention. Apart from media reports, there are a number of social science analyses of stem cell policy, therapy, and research, their ethical implications, and impact of advertising on patients. Nevertheless, in the media reports as well as in academic studies, experiences of patients, who undertake overseas journeys for stem cell therapy, have largely been either ignored or presented reductively, often as a "false hope." In this article, I analyze the experiences of patients and their "journeys of hope" to NuTech Mediworld, an embryonic stem cell therapy clinic in New Delhi, India. My analysis, which draws on my observations in the clinic and patients' experiences, instead of seeking to adjudicate whether embryonic stem cell therapy in clinics such as NuTech is right or wrong, true or false, focuses on how patients navigate and contest these concerns. I utilize Gilles Deleuze and Felix Guattari's "concepts," lines of flight and deterritorialization, to highlight how embryonic stem cell therapy's "political economy of hope" embodies deterritorialization of several "regimes of truth" and how these deterritorializations impact patients' experiences. © The Author(s) 2014.

Knockdown of miR-27a sensitizes colorectal cancer stem cells to TRAIL by promoting the formation of Apaf-1-caspase-9 complex

PubMed Central

Zhang, Rui; Xu, Jian; Zhao, Jian; Bai, Jinghui

2017-01-01

MicroRNAs have been proved to participate in multiple biological processes in cancers. For developing resistance to cytotoxic drug, cancer cells, especially the cancer stem cells, usually change their microRNA expression profile to survive in hostile environments. In the present study, we found that expression of microRNA-27a was increased in colorectal cancer stem cells. High level of microRNA-27a was indicated to induce the resistance to TNF-related apoptosis-inducing ligand (TRAIL). Knockdown of microRNA-27a resensitized colorectal cancer stem cells to TRAIL-induced cell death. Mechanically, the gene of Apaf-1, which is associated with the mitochondrial apoptosis, was demonstrated to be the target of microRNA-27a in colorectal cancer stem cells. Knockdown of microRNA-27a increased the expression level of Apaf-1, thus enhancing the formation of Apaf-1-caspase-9 complex and subsequently promoting the TRAIL-induced apoptosis in colorectal cancer stem cells. These findings suggested that knockdown of microRNA-27a in colorectal cancer stem cells by the specific antioligonucleotides was potential to reverse the chemoresistance to TRAIL. It may represent a novel therapeutic strategy for treating the colorectal cancer more effectively. PMID:28423356

Knockdown of miR-27a sensitizes colorectal cancer stem cells to TRAIL by promoting the formation of Apaf-1-caspase-9 complex.

PubMed

Zhang, Rui; Xu, Jian; Zhao, Jian; Bai, Jinghui

2017-07-11

MicroRNAs have been proved to participate in multiple biological processes in cancers. For developing resistance to cytotoxic drug, cancer cells, especially the cancer stem cells, usually change their microRNA expression profile to survive in hostile environments. In the present study, we found that expression of microRNA-27a was increased in colorectal cancer stem cells. High level of microRNA-27a was indicated to induce the resistance to TNF-related apoptosis-inducing ligand (TRAIL). Knockdown of microRNA-27a resensitized colorectal cancer stem cells to TRAIL-induced cell death. Mechanically, the gene of Apaf-1, which is associated with the mitochondrial apoptosis, was demonstrated to be the target of microRNA-27a in colorectal cancer stem cells. Knockdown of microRNA-27a increased the expression level of Apaf-1, thus enhancing the formation of Apaf-1-caspase-9 complex and subsequently promoting the TRAIL-induced apoptosis in colorectal cancer stem cells. These findings suggested that knockdown of microRNA-27a in colorectal cancer stem cells by the specific antioligonucleotides was potential to reverse the chemoresistance to TRAIL. It may represent a novel therapeutic strategy for treating the colorectal cancer more effectively.

Stem cells technology: a powerful tool behind new brain treatments.

PubMed

Duru, Lucienne N; Quan, Zhenzhen; Qazi, Talal Jamil; Qing, Hong

2018-06-18

Stem cell research has recently become a hot research topic in biomedical research due to the foreseen unlimited potential of stem cells in tissue engineering and regenerative medicine. For many years, medicine has been facing intense challenges, such as an insufficient number of organ donations that is preventing clinicians to fulfill the increasing needs. To try and overcome this regrettable matter, research has been aiming at developing strategies to facilitate the in vitro culture and study of stem cells as a tool for tissue regeneration. Meanwhile, new developments in the microfluidics technology brought forward emerging cell culture applications that are currently allowing for a better chemical and physical control of cellular microenvironment. This review presents the latest developments in stem cell research that brought new therapies to the clinics and how the convergence of the microfluidics technology with stem cell research can have positive outcomes on the fields of regenerative medicine and high-throughput screening. These advances will bring new translational solutions for drug discovery and will upgrade in vitro cell culture to a new level of accuracy and performance. We hope this review will provide new insights into the understanding of new brain treatments from the perspective of stem cell technology especially regarding regenerative medicine and tissue engineering.

Stem cells in pharmaceutical biotechnology.

PubMed

Zuba-Surma, Ewa K; Józkowicz, Alicja; Dulak, Józef

2011-11-01

Multiple populations of stem cells have been indicated to potentially participate in regeneration of injured organs. Especially, embryonic stem cells (ESC) and recently inducible pluripotent stem cells (iPS) receive a marked attention from scientists and clinicians for regenerative medicine because of their high proliferative and differentiation capacities. Despite that ESC and iPS cells are expected to give rise into multiple regenerative applications when their side effects are overcame during appropriate preparation procedures, in fact their most recent application of human ESC may, however, reside in their use as a tool in drug development and disease modeling. This review focuses on the applications of stem cells in pharmaceutical biotechnology. We discuss possible relevance of pluripotent cell stem populations in developing physiological models for any human tissue cell type useful for pharmacological, metabolic and toxicity evaluation necessary in the earliest steps of drug development. The present models applied for preclinical drug testing consist of primary cells or immortalized cell lines that show limitations in terms of accessibility or relevance to their in vivo counterparts. The availability of renewable human cells with functional similarities to their in vivo counterparts is the first landmark for a new generation of cell-based assays. We discuss the approaches for using stem cells as valuable physiological targets of drug activity which may increase the strength of target validation and efficacy potentially resulting in introducing new safer remedies into clinical trials and the marketplace. Moreover, we discuss the possible applications of stem cells for elucidating mechanisms of disease pathogenesis. The knowledge about the mechanisms governing the development and progression of multitude disorders which would come from the cellular models established based on stem cells, may give rise to new therapeutical strategies for such diseases. All together, the applications of various cell types derived from patient specific pluripotent stem cells may lead to targeted drug and cellular therapies for certain individuals.

Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

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

Varga, Nora; Vereb, Zoltan; Rajnavoelgyi, Eva

2011-10-28

Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth ofmore » undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.« less

Cancer stem cells and cell size: A causal link?

PubMed

Li, Qiuhui; Rycaj, Kiera; Chen, Xin; Tang, Dean G

2015-12-01

The majority of normal animal cells are 10-20 μm in diameter. Many signaling mechanisms, notably PI3K/Akt/mTOR, Myc, and Hippo pathways, tightly control and coordinate cell growth, cell size, cell division, and cell number during homeostasis. These regulatory mechanisms are frequently deregulated during tumorigenesis resulting in wide variations in cell sizes and increased proliferation in cancer cells. Here, we first review the evidence that primitive stem cells in adult tissues are quiescent and generally smaller than their differentiated progeny, suggesting a correlation between small cell sizes with the stemness. Conversely, increased cell size positively correlates with differentiation phenotypes. We then discuss cancer stem cells (CSCs) and present some evidence that correlates cell sizes with CSC activity. Overall, a causal link between CSCs and cell size is relatively weak and remains to be rigorously assessed. In the future, optimizing methods for isolating cells based on size should help elucidate the connection between cancer cell size and CSC characteristics. Copyright © 2015 Elsevier Ltd. All rights reserved.

Importance of the stem cell microenvironment for ophthalmological cell-based therapy

PubMed Central

Wan, Peng-Xia; Wang, Bo-Wen; Wang, Zhi-Chong

2015-01-01

Cell therapy is a promising treatment for diseases that are caused by cell degeneration or death. The cells for clinical transplantation are usually obtained by culturing healthy allogeneic or exogenous tissue in vitro. However, for diseases of the eye, obtaining the adequate number of cells for clinical transplantation is difficult due to the small size of tissue donors and the frequent needs of long-term amplification of cells in vitro, which results in low cell viability after transplantation. In addition, the transplanted cells often develop fibrosis or degrade and have very low survival. Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPS) are also promising candidates for cell therapy. Unfortunately, the differentiation of ESCs can bring immune rejection, tumorigenicity and undesired differentiated cells, limiting its clinical application. Although iPS cells can avoid the risk of immune rejection caused by ES cell differentiation post-transplantation, the low conversion rate, the risk of tumor formation and the potentially unpredictable biological changes that could occur through genetic manipulation hinder its clinical application. Thus, the desired clinical effect of cell therapy is impaired by these factors. Recent research findings recognize that the reason for low survival of the implanted cells not only depends on the seeded cells, but also on the cell microenvironment, which determines the cell survival, proliferation and even reverse differentiation. When used for cell therapy, the transplanted cells need a specific three-dimensional structure to anchor and specific extra cellular matrix components in addition to relevant cytokine signaling to transfer the required information to support their growth. These structures present in the matrix in which the stem cells reside are known as the stem cell microenvironment. The microenvironment interaction with the stem cells provides the necessary homeostasis for cell maintenance and growth. A large number of studies suggest that to explore how to reconstruct the stem cell microenvironment and strengthen its combination with the transplanted cells are key steps to successful cell therapy. In this review, we will describe the interactions of the stem cell microenvironment with the stem cells, discuss the importance of the stem cell microenvironment for cell-based therapy in ocular diseases, and introduce the progress of stem cell-based therapy for ocular diseases. PMID:25815128

Advances of Stem Cell Therapeutics in Cutaneous Wound Healing and Regeneration.

PubMed

Kanji, Suman; Das, Hiranmoy

2017-01-01

Cutaneous wound healing is a complex multiple phase process, which overlaps each other, where several growth factors, cytokines, chemokines, and various cells interact in a well-orchestrated manner. However, an imbalance in any of these phases and factors may lead to disruption in harmony of normal wound healing process, resulting in transformation towards chronic nonhealing wounds and abnormal scar formation. Although various therapeutic interventions are available to treat chronic wounds, current wound-care has met with limited success. Progenitor stem cells possess potential therapeutic ability to overcome limitations of the present treatments as it offers accelerated wound repair with tissue regeneration. A substantial number of stem cell therapies for cutaneous wounds are currently under development as a result of encouraging preliminary findings in both preclinical and clinical studies. However, the mechanisms by which these stem cells contribute to the healing process have yet to be elucidated. In this review, we emphasize on the major treatment modalities currently available for the treatment of the wound, role of various interstitial stem cells and exogenous adult stem cells in cutaneous wound healing, and possible mechanisms involved in the healing process.

Proteasome expression and activity in cancer and cancer stem cells.

PubMed

Voutsadakis, Ioannis A

2017-03-01

Proteasome is a multi-protein organelle that participates in cellular proteostasis by destroying damaged or short-lived proteins in an organized manner guided by the ubiquitination signal. By being in a central place in the cellular protein complement homeostasis, proteasome is involved in virtually all cell processes including decisions on cell survival or death, cell cycle, and differentiation. These processes are important also in cancer, and thus, the proteasome is an important regulator of carcinogenesis. Cancers include a variety of cells which, according to the cancer stem cell theory, descend from a small percentage of cancer stem cells, alternatively termed tumor-initiating cells. These cells constitute the subsets that have the ability to propagate the whole variety of cancer and repopulate tumors after cytostatic therapies. Proteasome plays a role in cellular processes in cancer stem cells, but it has been found to have a decreased function in them compared to the rest of cancer cells. This article will discuss the transcriptional regulation of proteasome sub-unit proteins in cancer and in particular cancer stem cells and the relationship of the proteasome with the pluripotency that is the defining characteristic of stem cells. Therapeutic opportunities that present from the understanding of the proteasome role will also be discussed.

Pituitary Stem Cell Update and Potential Implications for Treating Hypopituitarism

PubMed Central

Castinetti, Frederic; Davis, Shannon W.; Brue, Thierry

2011-01-01

Stem cells have been identified in organs with both low and high cell turnover rates. They are characterized by the expression of key marker genes for undifferentiated cells, the ability to self-renew, and the ability to regenerate tissue after cell loss. Several recent reports present evidence for the presence of pituitary stem cells. Here we offer a critical review of the field and suggest additional studies that could resolve points of debate. Recent reports have relied on different markers, including SOX2, nestin, GFRa2, and SCA1, to identify pituitary stem cells and progenitors. Future studies will be needed to resolve the relationships between cells expressing these markers. Members of the Sox family of transcription factors are likely involved in the earliest steps of pituitary stem cell proliferation and the earliest transitions to differentiation. The transcription factor PROP1 and the NOTCH signaling pathway may regulate the transition to differentiation. Identification of the stem cell niche is an important step in understanding organ development. The niche may be the marginal zone around the lumen of Rathke's pouch, between the anterior and intermediate lobes of mouse pituitary, because cells in this region apparently give birth to all six pituitary hormone cell lineages. Stem cells have been shown to play a role in recurrent malignancies in some tissues, and their role in pituitary hyperplasia, pituitary adenomas, and tumors is an important area for future investigation. From a therapeutic viewpoint, the ability to cultivate and grow stem cells in a pituitary predifferentiation state might also be helpful for the long-term treatment of pituitary deficiencies. PMID:21493869

Characterization and Classification of Mesenchymal Stem Cells in Several Species Using Surface Markers for Cell Therapy Purposes.

PubMed

Ghaneialvar, Hori; Soltani, Leila; Rahmani, Hamid Reza; Lotfi, Abbas Sahebghadam; Soleimani, Masoud

2018-01-01

Mesenchymal stem cells are multipotent cells capable of replicating as undifferentiated cells, and have the potential of differentiating into mesenchymal tissue lineages such as osteocytes, adipocytes and chondrocytes. Such lineages can then be used in cell therapy. The aim of present study was to characterize bone marrow derived mesenchymal stem cells in four different species, including: sheep, goat, human and mouse. Human bone-marrow mesenchymal stem cells were purchased, those of sheep and goat were isolated from fetal bone marrow, and those of mouse were collected by washing bone cavity of femur and tibia with DMEM/F12. Using flow-cytometry, they were characterized by CD surface antigens. Furthermore, cells of third passage were examined for their osteogenic and adipogenic differentiation potential by oil red and alizarin red staining respectively. According to the results, CD markers studied in the four groups of mesenchymal stem cells showed a different expression. Goat and sheep expressed CD44 and CD166, and weakly expressed CD34, CD45, CD105 and CD90. Similarly, human and mouse mesenchymal cells expressed CD44, CD166, CD105 and CD90 whereas the expression of CD34 and CD45 was negative. In conclusion, although all mesenchymal stem cells display plastic adherence and tri-lineage differentiation, not all express the same panel of surface antigens described for human mesenchymal stem cells. Additional panel of CD markers are necessary to characterize regenerative potential and possible application of these stem cells in regenerative medicine and implantology.

Effect of Induced Pluripotent Stem Cell Technology in Blood Banking

PubMed Central

Focosi, Daniele

2016-01-01

Summary Population aging has imposed cost-effective alternatives to blood donations. Artificial blood is still at the preliminary stages of development, and the need for viable cells seems unsurmountable. Because large numbers of viable cells must be promptly available for clinical use, stem cell technologies, expansion, and banking represent ideal tools to ensure a regular supply. Provided key donors can be identified, induced pluripotent stem cell (iPSC) technology could pave the way to a new era in transfusion medicine, just as it is already doing in many other fields of medicine. The present review summarizes the current state of research on iPSC technology in the field of blood banking, highlighting hurdles, and promises. Significance The aging population in Western countries is causing a progressive reduction of blood donors and a constant increase of blood recipients. Because blood is the main therapeutic option to treat acute hemorrhage, cost-effective alternatives to blood donations are being actively investigated. The enormous replication capability of induced pluripotent stem cells and their promising results in many other fields of medicine could be an apt solution to produce the large numbers of viable cells required in transfusion and usher in a new era in transfusion medicine. The present report describes the potentiality, technological hurdles, and promises of induced pluripotent stem cells to generate red blood cells by redifferentiation. PMID:26819256

Stimulation of ovarian stem cells by follicle stimulating hormone and basic fibroblast growth factor during cortical tissue culture.

PubMed

Parte, Seema; Bhartiya, Deepa; Manjramkar, Dhananjay D; Chauhan, Anahita; Joshi, Amita

2013-04-01

Cryopreserved ovarian cortical tissue acts as a source of primordial follicles (PF) which can either be auto-transplanted or cultured in vitro to obtain mature oocytes. This offers a good opportunity to attain biological parenthood to individuals with gonadal insufficiency including cancer survivors. However, role of various intra- and extra-ovarian factors during PF growth initiation still remain poorly understood. Ovarian biology has assumed a different dimension due to emerging data on presence of pluripotent very small embryonic-like stem cells (VSELs) and ovarian germ stem cells (OGSCs) in ovary surface epithelium (OSE) and the concept of postnatal oogenesis. The present study was undertaken to decipher effect of follicle stimulating hormone (FSH) and basic fibroblast growth factor (bFGF) on the growth initiation of PF during organ culture with a focus on ovarian stem cells. Serum-free cultures of marmoset (n=3) and human (young and peri-menopausal) ovarian cortical tissue pieces were established. Cortical tissue pieces stimulated with FSH (0.5 IU/ml) or bFGF (100 ng/ml) were collected on Day 3 for histological and molecular studies. Gene transcripts specific for pluripotency (Oct-4A, Nanog), early germ cells (Oct-4, c-Kit, Vasa) and to reflect PF growth initiation (oocyte-specific Gdf-9 and Lhx8, and granulosa cells specific Amh) were studied by q-RTPCR. A prominent proliferation of OSE (which harbors stem cells) and transition of PF to primary follicles was observed after FSH and bFGF treatment. Ovarian stem cells were found to be released on the culture inserts and retained the potential to spontaneously differentiate into oocyte-like structures in extended cultures. q-RTPCR analysis revealed an increased expression of gene transcripts specific for VSELs, OGSCs and early germ cells suggestive of follicular transition. The present study shows that both FSH and bFGF stimulate stem cells present in OSE and also lead to PF growth initiation. Thus besides being a source of PF, cryopreserved ovarian cortical tissue could also be a source of stem cells which retain the ability to spontaneously differentiate into oocyte-like structures in vitro. Results provide a paradigm shift in the basic understanding of FSH action and also offer a new perspective to the field of oncofertility research.

How do culture media influence in vitro perivascular cell behavior?

PubMed

Huber, Birgit; Volz, Ann-Cathrin; Kluger, Petra Juliane

2015-12-01

Perivascular cells are multilineage cells located around the vessel wall and important for wall stabilization. In this study, we evaluated a stem cell media and a perivascular cell-specific media for the culture of primary perivascular cells regarding their cell morphology, doubling time, stem cell properties, and expression of cell type-specific markers. When the two cell culture media were compared to each other, perivascular cells cultured in the stem cell medium had a more elongated morphology and a faster doubling rate and cells cultured in the pericyte medium had a more typical morphology, with several filopodia, and a slower doubling rate. To evaluate stem cell properties, perivascular cells, CD146(-) cells, and mesenchymal stem cells (MSCs) were differentiated into the adipogenic, osteogenic, and chondrogenic lineages. It was seen that perivascular cells, as well as CD146(-) cells and MSCs, cultured in stem cell medium showed greater differentiation than cells cultured in pericyte-specific medium. The expression of pericyte-specific markers CD146, neural/glial antigen 2 (NG2), platelet-derived growth factor receptor-β (PDGFR-β), myosin, and α-smooth muscle actin (α-SMA) could be found in both pericyte cultures, as well as to varying amounts in CD146(-) cells, MSCs, and endothelial cells. The here presented work shows that perivascular cells can adapt to their in vitro environment and cell culture conditions influence cell functionality, such as doubling rate or differentiation behavior. Pericyte-specific markers were shown to be expressed also from cells other than perivascular cells. We can further conclude that CD146(+) perivascular cells are inhomogeneous cell population probably containing stem cell subpopulations, which are located perivascular around capillaries. © 2015 International Federation for Cell Biology.

Nanotopography Promotes Pancreatic Differentiation of Human Embryonic Stem Cells and Induced Pluripotent Stem Cells.

PubMed

Kim, Jong Hyun; Kim, Hyung Woo; Cha, Kyoung Je; Han, Jiyou; Jang, Yu Jin; Kim, Dong Sung; Kim, Jong-Hoon

2016-03-22

Although previous studies suggest that nanotopographical features influence properties and behaviors of stem cells, only a few studies have attempted to derive clinically useful somatic cells from human pluripotent stem cells using nanopatterned surfaces. In the present study, we report that polystyrene nanopore-patterned surfaces significantly promote the pancreatic differentiation of human embryonic and induced pluripotent stem cells. We compared different diameters of nanopores and showed that 200 nm nanopore-patterned surfaces highly upregulated the expression of PDX1, a critical transcription factor for pancreatic development, leading to an approximately 3-fold increase in the percentage of differentiating PDX1(+) pancreatic progenitors compared with control flat surfaces. Furthermore, in the presence of biochemical factors, 200 nm nanopore-patterned surfaces profoundly enhanced the derivation of pancreatic endocrine cells producing insulin, glucagon, or somatostatin. We also demonstrate that nanopore-patterned surface-induced upregulation of PDX1 is associated with downregulation of TAZ, suggesting the potential role of TAZ in nanopore-patterned surface-mediated mechanotransduction. Our study suggests that appropriate cytokine treatments combined with nanotopographical stimulation could be a powerful tool for deriving a high purity of desired cells from human pluripotent stem cells.

Boron neutron capture therapy induces cell cycle arrest and cell apoptosis of glioma stem/progenitor cells in vitro

PubMed Central

2013-01-01

Background Glioma stem cells in the quiescent state are resistant to clinical radiation therapy. An almost inevitable glioma recurrence is due to the persistence of these cells. The high linear energy transfer associated with boron neutron capture therapy (BNCT) could kill quiescent and proliferative cells. Methods The present study aimed to evaluate the effects of BNCT on glioma stem/progenitor cells in vitro. The damage induced by BNCT was assessed using cell cycle progression, apoptotic cell ratio and apoptosis-associated proteins expression. Results The surviving fraction and cell viability of glioma stem/progenitor cells were decreased compared with differentiated glioma cells using the same boronophenylalanine pretreatment and the same dose of neutron flux. BNCT induced cell cycle arrest in the G2/M phase and cell apoptosis via the mitochondrial pathway, with changes in the expression of associated proteins. Conclusions Glioma stem/progenitor cells, which are resistant to current clinical radiotherapy, could be effectively killed by BNCT in vitro via cell cycle arrest and apoptosis using a prolonged neutron irradiation, although radiosensitivity of glioma stem/progenitor cells was decreased compared with differentiated glioma cells when using the same dose of thermal neutron exposure and boronophenylalanine pretreatment. Thus, BNCT could offer an appreciable therapeutic advantage to prevent tumor recurrence, and may become a promising treatment in recurrent glioma. PMID:23915425

Concise Review: Inner Ear Stem Cells—An Oxymoron, But Why?

PubMed Central

Ronaghi, Mohammad; Nasr, Marjan; Heller, Stefan

2012-01-01

Hearing loss, caused by irreversible loss of cochlear sensory hair cells, affects millions of patients worldwide. In this concise review, we examine the conundrum of inner ear stem cells, which obviously are present in the inner ear sensory epithelia of nonmammalian vertebrates, giving these ears the ability to functionally recover even from repetitive ototoxic insults. Despite the inability of the mammalian inner ear to regenerate lost hair cells, there is evidence for cells with regenerative capacity because stem cells can be isolated from vestibular sensory epithelia and from the neonatal cochlea. Challenges and recent progress toward identification of the intrinsic and extrinsic signaling pathways that could be used to re-establish stemness in the mammalian organ of Corti are discussed. PMID:22102534

Concise review: Inner ear stem cells--an oxymoron, but why?

PubMed

Ronaghi, Mohammad; Nasr, Marjan; Heller, Stefan

2012-01-01

Hearing loss, caused by irreversible loss of cochlear sensory hair cells, affects millions of patients worldwide. In this concise review, we examine the conundrum of inner ear stem cells, which obviously are present in the inner ear sensory epithelia of nonmammalian vertebrates, giving these ears the ability to functionally recover even from repetitive ototoxic insults. Despite the inability of the mammalian inner ear to regenerate lost hair cells, there is evidence for cells with regenerative capacity because stem cells can be isolated from vestibular sensory epithelia and from the neonatal cochlea. Challenges and recent progress toward identification of the intrinsic and extrinsic signaling pathways that could be used to re-establish stemness in the mammalian organ of Corti are discussed. Copyright © 2011 AlphaMed Press.

MUC4 stabilizes HER2 expression and maintains the cancer stem cell population in ovarian cancer cells.

PubMed

Ponnusamy, Moorthy P; Seshacharyulu, Parthasarathy; Vaz, Arokiapriyanka; Dey, Parama; Batra, Surinder K

2011-04-26

Recent evidence has suggested that the capability of cancer to grow, propagate and relapse after therapy is dependent on a small subset of the cell population within the tumor, called cancer stem cells. Therefore, this subpopulation of cells needs to be targeted with different approaches by identification of unique stem-cell specific target antigens. One of the well known tumor antigens is the epithelial cell mucin MUC4, which is aberrantly expressed in ovarian cancer as compared to the normal ovary and plays a pivotal role in the aggressiveness and metastasis of ovarian cancer cells. In the present study, we aimed to analyze the cancer stem cell population in MUC4 overexpressed ovarian cancer cells. MUC4 was ectopically overexpressed in SKOV3 ovarian cancer cells. Western blot analysis was performed for MUC4, HER2, CD133, ALDH1 and Shh expression in MUC4 overexpressed cells. Confocal analysis of MUC4, HER2 and CD133 was also done in the MUC4 overexpressed cells. CD133 and Hoechst33342 dye staining was used to analyze the cancer stem cell population via FACS method in SKOV3-MUC4 cells. MUC4 overexpressed SKOV3 cells showed an increased expression of HER2 compared to control cells. MUC4 overexpression leads to increased (0.1%) side population (SP) and CD133-positive cancer stem cells compared to the control cells. Interestingly, the tumor sphere type circular colony formation was observed only in the MUC4 overexpressed ovarian cancer cells. Furthermore, the cancer stem cell marker CD133 was expressed along with MUC4 in the isolated circular colonies as analyzed by both confocal and western blot analysis. HER2 and cancer stem cell specific marker ALDH1 along with Shh, a self-renewal marker, showed increased expression in the isolated circular colonies compared to MUC4-transfected cells. These studies demonstrate that MUC4 overexpression leads to an enriched ovarian cancer stem cell population either directly or indirectly through HER2. In future, this study would be helpful for MUC4-directed therapy for the ovarian cancer stem cell population.

MUC4 stabilizes HER2 expression and maintains the cancer stem cell population in ovarian cancer cells

PubMed Central

2011-01-01

Background Recent evidence has suggested that the capability of cancer to grow, propagate and relapse after therapy is dependent on a small subset of the cell population within the tumor, called cancer stem cells. Therefore, this subpopulation of cells needs to be targeted with different approaches by identification of unique stem-cell specific target antigens. One of the well known tumor antigens is the epithelial cell mucin MUC4, which is aberrantly expressed in ovarian cancer as compared to the normal ovary and plays a pivotal role in the aggressiveness and metastasis of ovarian cancer cells. In the present study, we aimed to analyze the cancer stem cell population in MUC4 overexpressed ovarian cancer cells. Methods MUC4 was ectopically overexpressed in SKOV3 ovarian cancer cells. Western blot analysis was performed for MUC4, HER2, CD133, ALDH1 and Shh expression in MUC4 overexpressed cells. Confocal analysis of MUC4, HER2 and CD133 was also done in the MUC4 overexpressed cells. CD133 and Hoechst33342 dye staining was used to analyze the cancer stem cell population via FACS method in SKOV3-MUC4 cells. Results MUC4 overexpressed SKOV3 cells showed an increased expression of HER2 compared to control cells. MUC4 overexpression leads to increased (0.1%) side population (SP) and CD133-positive cancer stem cells compared to the control cells. Interestingly, the tumor sphere type circular colony formation was observed only in the MUC4 overexpressed ovarian cancer cells. Furthermore, the cancer stem cell marker CD133 was expressed along with MUC4 in the isolated circular colonies as analyzed by both confocal and western blot analysis. HER2 and cancer stem cell specific marker ALDH1 along with Shh, a self-renewal marker, showed increased expression in the isolated circular colonies compared to MUC4-transfected cells. Conclusion These studies demonstrate that MUC4 overexpression leads to an enriched ovarian cancer stem cell population either directly or indirectly through HER2. In future, this study would be helpful for MUC4-directed therapy for the ovarian cancer stem cell population. PMID:21521521

Clonogenic colony-forming ability of flow cytometrically isolated hepatic progenitor cells in the murine fetal liver.

PubMed

Taniguchi, H; Kondo, R; Suzuki, A; Zheng, Y W; Takada, Y; Fukunaga, K; Seino, K; Yuzawa, K; Otsuka, M; Fukao, K; Nakauchi, H

2000-01-01

Stem cells are defined as cells having multilineage differentiation potential and self-renewal capability. Hepatic stem cells have aroused considerable interest not only because of their developmental importance but also for their therapeutic potential. However, their presence in the liver has not yet been demonstrated. With the use of a fluorescence-activated cell sorter (FACS) and monoclonal antibodies, we attempted to ascertain whether hepatic stem cells are present in the murine fetal liver. For this purpose, we optimized a cell isolation technique for FACS sorting of fetal liver cells. When isolated CD45 TER119 cells (the non-blood cell fraction in the fetal liver) were tested for their clonogenic colony-forming ability, mechanical dissociation (pipetting) was the most suitable cell isolation technique for FACS sorting. We confirmed that these colonies contained not only cells expressing hepatocyte markers but also cells expressing cholangiocyte markers. To identify hepatic stem cells, studies must focus on CD45TER119- cells in the murine fetal liver.

Aberrantly regulated dysadherin and B-cell lymphoma 2/B-cell lymphoma 2-associated X enhances tumorigenesis and DNA targeting drug resistance of liver cancer stem cells

PubMed Central

JIANG, NAN; CHEN, WEI; ZHANG, JIAN-WEN; LI, YANG; ZENG, XIAN-CHENG; ZHANG, TONG; FU, BIN-SHENG; YI, HUI-MIN; ZHANG, QI

2015-01-01

Cancer stem cells (CSCs) in hepatocellular carcinoma (HCC) are frequently resistant to current therapeutic regimens and therefore responsible for tumor recurrence. Previous studies have reported that expression levels of dysadherin in CSCs may be used as a prognostic indicator, which is also responsible for treatment failure and poor survival rates. The present study analyzed the association of enhanced dysadherin levels with drug resistance and evasion of apoptosis in human HCC SP cells. An SP of 3.7% was isolated from human HCC cells using fluorescence-activated cell sorting. These SP cells displayed elevated levels of dysadherin and stemness proteins as well as high resistance to chemotherapeutic drugs and apoptosis. In order to reveal the possible link between dysadherin levels and tumorigenesis of SP cells, small interfering RNA technology was used to knockdown the expression of dysadherin in SP cells. Of note, the siRNA-transfected SP cells showed significantly reduced levels of stemness proteins, and were more sensitive to DNA-targeting drugs and apoptotic cell death as compared to non-transfected cells. Furthermore, in vivo experiments in NON/SCID mice indicated that dysadherin-expressing SP cells were highly tumorigenic, as they were able to induce tumor growth. The SP cell-derived tumor tissues in turn showed elevated dysadherin levels. The results of the present study therefore suggested that knockdown of dysadherin suppressed the tumorigenic properties of cancer stem-like SP cells. Hence, dysadherin is a valuable potential target for the development of novel anti-cancer drugs. PMID:26458963

A chemical approach to myocardial protection and regeneration.

PubMed

Piccoli, Marco; Cirillo, Federica; Tettamanti, Guido; Anastasia, Luigi

2016-04-28

The possibility of generating induced pluripotent stem cells from mouse embryonic fibroblasts and human adult fibroblasts has introduced new perspectives for possible therapeutic strategies to repair damaged hearts. However, obtaining large numbers of adult stem cells is still an ongoing challenge, and the safety of genetic reprogramming with lenti- or retro-viruses has several drawbacks not easy to be addressed. Furthermore, the majority of adult stem cell-based clinical trials for heart regeneration have had generally poor and controversial results. Nonetheless, it is now clear that the injected cells activate the growth and differentiation of progenitor cells that are already present in the heart. This is achieved by the release of signalling factors and/or exosomes carrying them. Along this line, chemistry may play a major role in developing new strategies for activating resident stem cells to regenerate the heart. In particular, this review focuses on small molecule approaches for cell reprogramming, cell differentiation, and activation of cell protection.

Stem cells and bone: a historical perspective.

PubMed

Bianco, Paolo

2015-01-01

Bone physiology and stem cells were tightly intertwined with one another, both conceptually and experimentally, long before the current explosion of interest in stem cells and so-called regenerative medicine. Bone is home to the two best known and best characterized systems of postnatal stem cells, and it is the only organ in which two stem cells and their dependent lineages coordinate the overall adaptive responses of two major physiological systems. All along, the nature and the evolutionary significance of the interplay of bone and hematopoiesis have remained a major scientific challenge, but also allowed for some of the most spectacular developments in cell biology-based medicine, such as hematopoietic stem cell transplantation. This question recurs in novel forms at multiple turning points over time: today, it finds in the biology of the "niche" its popular phrasing. Entirely new avenues of investigation emerge as a new view of bone in physiology and medicine is progressively established. Looking at bone and stem cells in a historical perspective provides a unique case study to highlight the general evolution of science in biomedicine since the end of World War II to the present day. A paradigm shift in science and in its relation to society and policies occurred in the second half of the XXth century, with major implications thereof for health, industry, drug development, market and society. Current interest in stem cells in bone as in other fields is intertwined with that shift. New opportunities and also new challenges arise. This article is part of a Special Issue entitled "Stem cells and bone". Copyright © 2014. Published by Elsevier Inc.

Challenges of stem cell-based pulp and dentin regeneration: a clinical perspective.

PubMed

Huang, George T-J; Al-Habib, Mey; Gauthier, Philippe

2013-03-01

There are two types of approaches to regenerate tissues: cell-based and cell-free. The former approach is to introduce exogenous cells into the host to regenerate tissues, and the latter is to use materials other than cells in an attempt to regenerate tissues. There has been a significant advancement in stem cell-based pulp and dentin regeneration research in the past few years. Studies in small and large animals have demonstrated that pulp/dentin-like tissues can be regenerated partially or completely in the root canal space with apical openings of 0.7-3.0 mm using dental pulp stem cells, including stem cells from apical papilla (SCAP) and subpopulations of pulp stem cells. Bone marrow mesenchymal stem cells (BMMSCs) and adipose tissue-derived MSCs (ADMSCs) have also been shown to regenerate pulp-like tissue. In contrast, the cell-free approach has not produced convincing evidence on pulp regeneration. However, one crucial concept has not been considered nor defined in the field of pulp/dentin regeneration and that is the critical size defect of dentin and pulp. Without such consideration and definition, it is difficult to predict or anticipate the extent of cell-free pulp regeneration that would occur. By reasoning, cell-free therapy is unlikely to regenerate an organ/tissue after total loss. Similarly, after a total loss of pulp, it is unlikely to regenerate without using exogenously introduced cells. A cell homing approach may provide a limited amount of tissue regeneration. Although stem cell-based pulp/dentin regeneration has shown great promise, clinical trials are difficult to launch at present. This article will address several issues that challenge and hinder the clinical applications of pulp/dentin regeneration which need to be overcome before stem cell-based pulp/dentin regeneration can occur in the clinic.

Challenges of stem cell-based pulp and dentin regeneration: a clinical perspective

PubMed Central

HUANG, GEORGE T.-J.; AL-HABIB, MEY; GAUTHIER, PHILIPPE

2013-01-01

There are two types of approaches to regenerate tissues: cell-based and cell-free. The former approach is to introduce exogenous cells into the host to regenerate tissues, and the latter is to use materials other than cells in an attempt to regenerate tissues. There has been a significant advancement in stem cell-based pulp and dentin regeneration research in the past few years. Studies in small and large animals have demonstrated that pulp/dentin-like tissues can be regenerated partially or completely in the root canal space with apical openings of 0.7-3.0 mm using dental pulp stem cells, including stem cells from apical papilla (SCAP) and subpopulations of pulp stem cells. Bone marrow mesenchymal stem cells (BMMSCs) and adipose tissue-derived MSCs (ADMSCs) have also been shown to regenerate pulp-like tissue. In contrast, the cell-free approach has not produced convincing evidence on pulp regeneration. However, one crucial concept has not been considered nor defined in the field of pulp/dentin regeneration and that is the critical size defect of dentin and pulp. Without such consideration and definition, it is difficult to predict or anticipate the extent of cell-free pulp regeneration that would occur. By reasoning, cell-free therapy is unlikely to regenerate an organ/tissue after total loss. Similarly, after a total loss of pulp, it is unlikely to regenerate without using exogenously introduced cells. A cell homing approach may provide a limited amount of tissue regeneration. Although stem cell-based pulp/dentin regeneration has shown great promise, clinical trials are difficult to launch at present. This article will address several issues that challenge and hinder the clinical applications of pulp/dentin regeneration which need to be overcome before stem cell-based pulp/dentin regeneration can occur in the clinic. PMID:23914150

[Stem cells: searching predisposition to cardiac commitment by surface markers expression].

PubMed

Lara-Martínez, Luis A; Gutiérrez-Villegas, Ingrid; Arenas-Luna, Victor M; Hernández-Gutierrez, Salomón

2018-01-05

It is well-known that cardiovascular diseases are the leading cause of death worldwide, and represent an important economic burden to health systems. In an attempt to solve this problem, stem cell therapy has emerged as a therapeutic option. Within the last 20 years, a great variety of stem cells have been used in different myocardial infarction models. Up until now, the use of cardiac stem cells (CSCs) has seemed to be the best option, but the inaccessibility and scarcity of these cells make their use unreliable. Additionally, there is a high risk as they have to be obtained directly from the heart of the patient. Unlike CSCs, adult stem cells originating from bone marrow or adipose tissue, among others, appear to be an attractive option due to their easier accessibility and abundance, but particularly due to the probable existence of cardiac progenitors among their different sub-populations. In this review an analysis is made of the surface markers present in CSCs compared with other adult stem cells. This suggested the pre-existence of cells sharing specific surface markers with CSCs, a predictable immunophenotype present in some cells, although in low proportions, and with a potential of cardiac differentiation that could be similar to CSCs, thus increasing their therapeutic value. This study highlights new perspectives regarding MSCs that would enable some of these sub-populations to be differentiated at cardiac tissue level. Copyright © 2017 Instituto Nacional de Cardiología Ignacio Chávez. Publicado por Masson Doyma México S.A. All rights reserved.

MicroRNA‑141 inhibits the self‑renewal of glioblastoma stem cells via Jagged1.

PubMed

Gao, Xianfeng; Zhu, Xiaobo; Sun, Yang; Liu, Jingwei

2017-07-01

Glioblastoma multiforme is one of the most lethal types of brain cancer. With limited success from conventional therapies, the cancer stem cell theory was developed, and investigation into microRNAs (miRs) has facilitated understanding of this theory. The present study demonstrated that miR‑141 is suppressed in sorted cluster of differentiation (CD) 133(+) glioblastoma stem cells (GSCs) compared with CD133(‑) non‑glioblastoma stem cells (NSCs) from patient samples. In addition, miR‑141 overexpression inhibited the sphere formation ability of GSCs in vitro and in vivo. Furthermore, Jagged1 may reverse the effect of miR‑141; miR‑141 was revealed to target the 3'‑untranslated region of Jagged1, thereby inhibiting the stemness of GSCs. Thus, miR‑141 may serve as a potent antioncomir targeting cancer stem cells, and may facilitate the development of therapeutic targets to prolong the overall survival of patients with glioblastoma.

Characterization of insulin-producing cells derived from PDX-1-transfected neural stem cells.

PubMed

Wang, Hailan; Jiang, Zesheng; Li, Aihui; Gao, Yi

2012-12-01

Islet cell transplantation is a promising treatment strategy for type-1 diabetes. However, functional islet cells are hard to obtain for transplantation and are in short supply. Directing the differentiation of stem cells into insulin‑producing cells, which serve as islet cells, would overcome this shortage. Bone marrow contains hematopoietic stem cells and mesenchymal stem cells. The present study used bone marrow cells isolated from rats and neural stem cells (NSCs) that were derived from bone marrow cells in culture. Strong nestin staining was detected in NSCs, but not in bone marrow stromal cells (BMSCs). In vitro transfection of the pancreatic duodenal homeobox-1 (PDX-1) gene into NSCs generated insulin‑producing cells. Reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) analysis confirmed that PDX-1-transfected NSCs expressed insulin mRNA and released insulin protein. However, insulin release from PDX-1-transfected NSCs did not respond to the challenge of glucose and glucagon-like peptide-1. These results support the use of bone marrow-derived NSCs as a renewable source of insulin-producing cells for autologous transplantation to treat type-1 diabetes.

Understanding the role of growth factors in modulating stem cell tenogenesis.

PubMed

Gonçalves, Ana I; Rodrigues, Márcia T; Lee, Sang-Jin; Atala, Anthony; Yoo, James J; Reis, Rui L; Gomes, Manuela E

2013-01-01

Current treatments for tendon injuries often fail to fully restore joint biomechanics leading to the recurrence of symptoms, and thus resulting in a significant health problem with a relevant social impact worldwide. Cell-based approaches involving the use of stem cells might enable tailoring a successful tendon regeneration outcome. As growth factors (GFs) powerfully regulate the cell biological response, their exogenous addition can further stimulate stem cells into the tenogenic lineage, which might eventually depend on stem cells source. In the present study we investigate the tenogenic differentiation potential of human- amniotic fluid stem cells (hAFSCs) and adipose-derived stem cells (hASCs) with several GFs associated to tendon development and healing; namely, EGF, bFGF, PDGF-BB and TGF-β1. Stem cells response to biochemical stimuli was studied by screening of tendon-related genes (collagen type I, III, decorin, tenascin C and scleraxis) and proteins found in tendon extracellular matrix (ECM) (Collagen I, III, and Tenascin C). Despite the fact that GFs did not seem to influence the synthesis of tendon ECM proteins, EGF and bFGF influenced the expression of tendon-related genes in hAFSCs, while EGF and PDGF-BB stimulated the genetic expression in hASCs. Overall results on cellular alignment morphology, immunolocalization and PCR analysis indicated that both stem cell source can be biochemically induced towards tenogenic commitment, validating the potential of hASCs and hAFSCs for tendon regeneration strategies.

Porous microscaffolds for 3D culture of dental pulp mesenchymal stem cells.

PubMed

Bhuptani, Ronak S; Patravale, Vandana B

2016-12-30

The collective power of stem cells due to their evident advantages is incessantly investigated in regenerative medicine to be the next generation exceptional remedy for tissue regeneration and treatment of diseases. Stem cells are highly sensitive and a 3D culture environment is a requisite for its successful transplantation and integration with tissues. Porous microscaffolds can create a 3D microenvironment for growing stems cells, controlling their fate both in vitro and in vivo. In the present study, interconnected porous PLGA microscaffolds were fabricated, characterized and employed to propagate human dental pulp mesenchymal stem cells (DPMSCs) in vitro. The porous topography was investigated by scanning electron microscopy and the pore size was controlled by fabrication conditions such as the concentration of porogen. DPMSCs were cultured on microscaffolds and were evaluated for their morphology, attachment, proliferation, cell viability via MTT and molecular expression (RT-PCR). DPMSCs were adequately proliferated and adhered over the microscaffolds forming a 3D cell-microscaffold construct. The average number of DPMSCs grown on PLGA microscaffolds was significantly higher than monolayer 2D culture during 5th and 7th day. Moreover, cell viability and gene expression results together corroborated that microscaffolds maintained the viability, stemness and plasticity of the cultured dental pulp mesenchymal stem cells. The novel porous microscaffold developed acts as promising scaffold for 3D culture and survival and transplantation of stem cells for tissue engineering. Copyright © 2016 Elsevier B.V. All rights reserved.

Data on the potential impact of food supplements on the growth of mouse embryonic stem cells.

PubMed

Correia, Marcelo; Sousa, Maria I; Rodrigues, Ana S; Perestrelo, Tânia; Pereira, Sandro L; Ribeiro, Marcelo F; Ramalho-Santos, João

2016-06-01

The use of new compounds as dietary supplements is increasing, but little is known in terms of possible consequences of their use. Pluripotent stem cells are a promising research tool for citotoxicological research for evaluation of proliferation, cell death, pluripotency and differentiation. Using the mouse embryonic stem cell (mESC) model, we present data on three different compounds that have been proposed as new potential supplements for co-adjuvant disease treatments: kaempferol, berberine and Tauroursodeoxycholic acid (TUDCA). Cell number and viability were monitored following treatment with increased concentrations of each drug in pluripotent culture conditions.

Stem cell technology for tendon regeneration: current status, challenges, and future research directions

PubMed Central

Lui, Pauline Po Yee

2015-01-01

Tendon injuries are a common cause of physical disability. They present a clinical challenge to orthopedic surgeons because injured tendons respond poorly to current treatments without tissue regeneration and the time required for rehabilitation is long. New treatment options are required. Stem cell-based therapies offer great potential to promote tendon regeneration due to their high proliferative, synthetic, and immunomodulatory activities as well as their potential to differentiate to the target cell types and undergo genetic modification. In this review, I first recapped the challenges of tendon repair by reviewing the anatomy of tendon. Next, I discussed the advantages and limitations of using different types of stem cells compared to terminally differentiated cells for tendon tissue engineering. The safety and efficacy of application of stem cells and their modified counterparts for tendon tissue engineering were then summarized after a systematic literature search in PubMed. The challenges and future research directions to enhance, optimize, and standardize stem cell-based therapies for augmenting tendon repair were then discussed. PMID:26715856

[Stem cell research and science and technology policy in Japan].

PubMed

Yashiro, Yoshimi

2011-12-01

In this paper I review the present condition of the regeneration medicine research using pluripotency and a somatic stem cell, and I describe the subject of the science and technology policy in Japan towards realization of regeneration medicine. The Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) supported research promotion by the prompt action in 2007 when establishment of the iPS cell was reported by Shinya Yamanaka. Although the hospitable support of the Japanese government to an iPS cell is continued still now, there are some problems in respect of the support to other stem cell researches, and industrialization of regeneration medicine. In order to win a place in highly competitive area of investigation, MEXT needs to change policy so that funds may be widely supplied also to stem cell researches other than iPS cell research.

The neurotrophic effects of different human dental mesenchymal stem cells.

PubMed

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

2017-10-03

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

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

PubMed

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

2018-01-01

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

World Stem Cell Summit 2014. 3-5 December 2014, San Antonio, TX, USA.

PubMed

Hasegawa, Kouichi; Asada, Takashi; Sengoku, Shintaro; Nakatsuji, Norio

2015-05-01

Among the many international conferences in the field of stem cells and regenerative medicine, WSCS is distinct in focusing its efforts to serve as the meeting point by multisector communities of research, clinics, industry, regulation, policy making and ethics. All are aiming at advancing stem cell innovation and new therapies, under the banner of 'connect, collaborate and cure'. As same as past years, presenters and attendees included not only researchers but also clinicians, funding agencies, government officials, industries and patients. Thus, many sessions focused on the clinical translation from basic research. Another important agenda were industrial and social aspects, and problems to be solved before realization of practical and sustainable stem cell-based therapies.

Biology of lung cancer: genetic mutation, epithelial-mesenchymal transition, and cancer stem cells.

PubMed

Aoi, Takashi

2016-09-01

At present, most cases of unresectable cancer cannot be cured. Genetic mutations, EMT, and cancer stem cells are three major issues linked to poor prognosis in such cases, all connected by inter- and intra-tumor heterogeneity. Issues on inter-/intra-tumor heterogeneity of genetic mutation could be resolved with recent and future technologies of deep sequencers, whereas, regarding such issues as the "same genome, different epigenome/phenotype", we expect to solve many of these problems in the future through further research in stem cell biology. We herein review and discuss the three major issues in the biology of cancers, especially from the standpoint of stem cell biology.

Autism Spectrum Disorders: Is Mesenchymal Stem Cell Personalized Therapy the Future?

PubMed Central

Siniscalco, Dario; Sapone, Anna; Cirillo, Alessandra; Giordano, Catia; Maione, Sabatino; Antonucci, Nicola

2012-01-01

Autism and autism spectrum disorders (ASDs) are heterogeneous neurodevelopmental disorders. They are enigmatic conditions that have their origins in the interaction of genes and environmental factors. ASDs are characterized by dysfunctions in social interaction and communication skills, in addition to repetitive and stereotypic verbal and nonverbal behaviours. Immune dysfunction has been confirmed with autistic children. There are no defined mechanisms of pathogenesis or curative therapy presently available. Indeed, ASDs are still untreatable. Available treatments for autism can be divided into behavioural, nutritional, and medical approaches, although no defined standard approach exists. Nowadays, stem cell therapy represents the great promise for the future of molecular medicine. Among the stem cell population, mesenchymal stem cells (MSCs) show probably best potential good results in medical research. Due to the particular immune and neural dysregulation observed in ASDs, mesenchymal stem cell transplantation could offer a unique tool to provide better resolution for this disease. PMID:22496609

Setting Global Standards for Stem Cell Research and Clinical Translation: The 2016 ISSCR Guidelines.

PubMed

Daley, George Q; Hyun, Insoo; Apperley, Jane F; Barker, Roger A; Benvenisty, Nissim; Bredenoord, Annelien L; Breuer, Christopher K; Caulfield, Timothy; Cedars, Marcelle I; Frey-Vasconcells, Joyce; Heslop, Helen E; Jin, Ying; Lee, Richard T; McCabe, Christopher; Munsie, Megan; Murry, Charles E; Piantadosi, Steven; Rao, Mahendra; Rooke, Heather M; Sipp, Douglas; Studer, Lorenz; Sugarman, Jeremy; Takahashi, Masayo; Zimmerman, Mark; Kimmelman, Jonathan

2016-06-14

The International Society for Stem Cell Research (ISSCR) presents its 2016 Guidelines for Stem Cell Research and Clinical Translation (ISSCR, 2016). The 2016 guidelines reflect the revision and extension of two past sets of guidelines (ISSCR, 2006; ISSCR, 2008) to address new and emerging areas of stem cell discovery and application and evolving ethical, social, and policy challenges. These guidelines provide an integrated set of principles and best practices to drive progress in basic, translational, and clinical research. The guidelines demand rigor, oversight, and transparency in all aspects of practice, providing confidence to practitioners and public alike that stem cell science can proceed efficiently and remain responsive to public and patient interests. Here, we highlight key elements and recommendations in the guidelines and summarize the recommendations and deliberations behind them. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Update on mesenchymal stem cell therapies for cartilage disorders

PubMed Central

Paschos, Nikolaos K; Sennett, Mackenzie L

2017-01-01

Cartilage disorders, including focal cartilage lesions, are among the most common clinical problems in orthopedic practice. Left untreated, large focal lesions may result in progression to osteoarthritis, with tremendous impact on the quality of life of affected individuals. Current management strategies have shown only a modest degree of success, while several upcoming interventions signify better outcomes in the future. Among these, stem cell therapies have been suggested as a promising new era for cartilage disorders. Certain characteristics of the stem cells, such as their potential to differentiate but also to support healing made them a fruitful candidate for lesions in cartilage, a tissue with poor healing capacity. The aim of this editorial is to provide an update on the recent advancements in the field of stem cell therapy for the management of focal cartilage defects. Our goal is to present recent basic science advances and to present the potential of the use of stem cells in novel clinical interventions towards enhancement of the treatment armamentarium for cartilage lesions. Furthermore, we highlight some thoughts for the future of cartilage regeneration and repair and to explore future perspectives for the next steps in the field. PMID:29312843

Nestin is expressed in HMB-45 negative melanoma cells in dermal parts of nodular melanoma.

PubMed

Kanoh, Maho; Amoh, Yasuyuki; Tanabe, Kenichi; Maejima, Hideki; Takasu, Hiroshi; Katsuoka, Kensei

2010-06-01

Nestin, a marker of neural stem cells, is expressed in the stem cells of the mouse hair follicle. The nestin-expressing hair follicle stem cells can differentiate into neurons, glia, keratocytes, smooth muscle cells and melanocytes in vitro. These pluripotent nestin-expressing stem cells are keratin 15 (K15)-negative, suggesting that they are in a relatively undifferentiated state. Recent studies suggest that the epithelial stem cells are important in tumorigenesis, and nestin expression is thought to be important in tumorigenesis. In the present study, we examined the expression of the hair follicle and neural stem cell marker nestin, as well as S-100 and HMB-45, in melanoma. Nestin immunoreactivity was observed in the HMB-45-negative melanoma cells in all five cases of amelanotic nodular melanomas. Moreover, nestin immunoreactivity was observed in the dermal parts in seven of 10 cases of melanotic nodular melanomas. Especially, nestin immunoreactivity was observed in the HMB-45-negative melanoma cells in the dermal parts of all 10 cases of HMB-45-negative amelanotic and melanotic nodular melanomas. On the other hand, nestin expression was negative in 10 of 12 cases of superficial spreading melanoma. These results suggest that nestin is an important marker of HMB-45-negative melanoma cells in the dermal parts of patients with nodular melanoma.

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. Copyright © 2014 John Wiley & Sons, Ltd.

Ocular surface involvements in ectrodactyly-ectodermal dysplasia-cleft syndrome.

PubMed

Kennedy, David P; Chandler, John W; McCulley, James P

2015-06-01

To present the ocular manifestation of 2 cases of ectrodactyly-ectodermal dysplasia-cleft syndrome, a multiple congenital anomaly syndrome caused by a single point mutation of the p63 gene that controls epidermal development and homeostasis and to present treatment options. Patient 1 presented with mild signs and symptoms of dry eye and limbal stem cell deficiency with retention of 20/30 vision. Patient 2 presented with severe signs and symptoms of limbal stem cell deficiency with diffuse corneal scarring and counting fingers vision. This second patient's course was complicated by allergic conjunctivitis and advanced steroid-induced glaucoma. The cause of visual loss in ectrodactyly-ectodermal dysplasia-cleft syndrome appears to be multifactorial and likely includes inflammation of the ocular surface, tear film abnormalities, eyelid abnormalities, and limbal stem cell deficiency. Treatment modalities including lubrication, contact lenses, and limbal stem cell transplantation are reviewed. The ophthalmic conditions seen in ectrodactyly-ectodermal dysplasia-cleft syndrome frequently lead to vision loss. Early correct diagnosis and appropriate therapy are paramount because p63 gene mutations have a critical role in maintaining the integrity of the ocular surface in the setting of limbal stem cell deficiency, especially if there are other ocular surface insults such as lid disease, meibomian gland dysfunction and toxicity from topical medications. Patients should be monitored at regular, frequent intervals; and particular attention should be taken to avoid adverse secondary effects of these conditions and medications. Copyright © 2015 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Transplantation of autologous bone marrow-derived mesenchymal stem cells for traumatic brain injury☆

PubMed Central

Jiang, Jindou; Bu, Xingyao; Liu, Meng; Cheng, Peixun

2012-01-01

Results from the present study demonstrated that transplantation of autologous bone marrow-derived mesenchymal stem cells into the lesion site in rat brain significantly ameliorated brain tissue pathological changes and brain edema, attenuated glial cell proliferation, and increased brain-derived neurotrophic factor expression. In addition, the number of cells double-labeled for 5-bromodeoxyuridine/glial fibrillary acidic protein and cells expressing nestin increased. Finally, blood vessels were newly generated, and the rats exhibited improved motor and cognitive functions. These results suggested that transplantation of autologous bone marrow-derived mesenchymal stem cells promoted brain remodeling and improved neurological functions following traumatic brain injury. PMID:25806058

Nanotechnology-based approaches for regenerative medicine and biosensing

NASA Astrophysics Data System (ADS)

Solanki, Aniruddh P.

The recent emergence of nanotechnology has set high expectations in many fields of science, especially in biology and medicine. Nanotechnology-based approaches are expected to solve key questions in the emerging field of regenerative medicine. Regenerative medicine essentially deals with regeneration of cells, ultimately leading to the formation of tissues and organs. For this purpose, stem cells, embryonic stem cells or adult stem cells, are thought to be ideal resources. However, many challenges need to be addressed before the full therapeutic potential of stem cells can be harnessed. Controlling the differentiation of stem cells into cells of a specific lineage is extremely vital and challenging. Addressing this challenge, in this work, novel nanotechnology-based approaches for controlling the differentiation of neural stem cells (NSCs) into neurons has been presented. Regeneration of damaged neurons, due to traumatic injuries or degenerative diseases, is extremely challenging. For this purpose, NSCs can be used as resources that can differentiate into neurons, thus having great potential in solving needs of many patients suffering from such conditions. For controlling the differentiation of stem cells, soluble cues (comprising of small molecules and biomolecules) and insoluble cues (cell-cell interactions and cell-microenvironment interactions) play a very important role. The delivery of soluble cues, such as genetic material, into stem cells is extremely challenging. The initial part of this work presents the use of nanomaterials for efficiently delivering soluble cues such as small molecules and small interfering RNA (siRNA) into NSCs for controlling their differentiation into neurons. However, for regenerative purposes, it is preferred that least amounts of the delivery vehicle be used. Thus, the following part of the thesis presents the development and applications of nanotechnology-based approaches for enhancing the differentiation of NSCs into neurons using insoluble cues. The cellular microenvironment, consisting for the extracellular matrix (ECM) was modified by the use of nanostructures, to deliver siRNA into NSCs to enhance neuronal differentiation. Nanotopography-mediated reverse uptake of only the siRNA molecules from the ECM was achieved by the NSCs. NSC differentiation was also controlled by the use of protein micropatterns, wherein the pattern geometry and size defined the fate of the NSCs. Lastly, graphene, in combination with nanoparticles was used as component of the ECM to not only enhance the differentiation of NSCs into neurons, but also align the axons of the differentiated NSCs, having significant implications for its use in regenerating injured spinal cords. The final portion of the thesis presents the applications of nanotechnology for developing highly sensitive and selective biosensors, for detecting biomarkers implicated in various diseases such as cancer and acute pancreatitis.

Mesenchymal stem cell-like properties of CD133+ glioblastoma initiating cells

PubMed Central

Pavon, Lorena Favaro; Sibov, Tatiana Tais; de Oliveira, Daniela Mara; Marti, Luciana C.; Cabral, Francisco Romero; de Souza, Jean Gabriel; Boufleur, Pamela; Malheiros, Suzana M.F.; de Paiva Neto, Manuel A.; da Cruz, Edgard Ferreira; Chudzinski-Tavassi, Ana Marisa; Cavalheiro, Sérgio

2016-01-01

Glioblastoma is composed of dividing tumor cells, stromal cells and tumor initiating CD133+ cells. Recent reports have discussed the origin of the glioblastoma CD133+ cells and their function in the tumor microenvironment. The present work sought to investigate the multipotent and mesenchymal properties of primary highly purified human CD133+ glioblastoma-initiating cells. To accomplish this aim, we used the following approaches: i) generation of tumor subspheres of CD133+ selected cells from primary cell cultures of glioblastoma; ii) analysis of the expression of pluripotency stem cell markers and mesenchymal stem cell (MSC) markers in the CD133+ glioblastoma-initiating cells; iii) side-by-side ultrastructural characterization of the CD133+ glioblastoma cells, MSC and CD133+ hematopoietic stem cells isolated from human umbilical cord blood (UCB); iv) assessment of adipogenic differentiation of CD133+ glioblastoma cells to test their MSC-like in vitro differentiation ability; and v) use of an orthotopic glioblastoma xenograft model in the absence of immune suppression. We found that the CD133+ glioblastoma cells expressed both the pluripotency stem cell markers (Nanog, Mush-1 and SSEA-3) and MSC markers. In addition, the CD133+ cells were able to differentiate into adipocyte-like cells. Transmission electron microscopy (TEM) demonstrated that the CD133+ glioblastoma-initiating cells had ultrastructural features similar to those of undifferentiated MSCs. In addition, when administered in vivo to non-immunocompromised animals, the CD133+ cells were also able to mimic the phenotype of the original patient's tumor. In summary, we showed that the CD133+ glioblastoma cells express molecular signatures of MSCs, neural stem cells and pluripotent stem cells, thus possibly enabling differentiation into both neural and mesodermal cell types. PMID:27244897

Iron depletion is a novel therapeutic strategy to target cancer stem cells

PubMed Central

Ninomiya, Takayuki; Ohara, Toshiaki; Noma, Kazuhiro; Katsura, Yuki; Katsube, Ryoichi; Kashima, Hajime; Kato, Takuya; Tomono, Yasuko; Tazawa, Hiroshi; Kagawa, Shunsuke; Shirakawa, Yasuhiro; Kimura, Fumiaki; Chen, Ling; Kasai, Tomonari; Seno, Masaharu; Matsukawa, Akihiro; Fujiwara, Toshiyoshi

2017-01-01

Adequate iron levels are essential for human health. However, iron overload can act as catalyst for the formation of free radicals, which may cause cancer. Cancer stem cells (CSCs), which maintain the hallmark stem cell characteristics of self-renewal and differentiation capacity, have been proposed as a driving force of tumorigenesis and metastases. In the present study, we investigated the role of iron in the proliferation and stemness of CSCs, using the miPS-LLCcm cell model. Although the anti-cancer agents fluorouracil and cisplatin suppressed the proliferation of miPS-LLCcm cells, these drugs did not alter the expression of stemness markers, including Nanog, SOX2, c-Myc, Oct3/4 and Klf4. In contrast, iron depletion by the iron chelators deferasirox and deferoxamine suppressed the proliferation of miPS-LLCcm cells and the expression of stemness markers. In an allograft model, deferasirox inhibited the growth of miPS-LLCcm implants, which was associated with decreased expression of Nanog and Sox2. Altogether, iron appears to be crucial for the proliferation and maintenance of stemness of CSCs, and iron depletion may be a novel therapeutic strategy to target CSCs. PMID:29228699

The usefulness of three-dimensional cell culture in induction of cancer stem cells from esophageal squamous cell carcinoma cell lines

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

Fujiwara, Daisuke; Kato, Kazunori, E-mail: kzkatou@juntendo.ac.jp; Department of Atopy Research Center, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421

2013-05-17

Highlights: •Spheroids were created from esophageal carcinoma cells using NanoCulture® Plates. •The proportion of strongly ALDH-positive cells increased in 3-D culture. •Expression of cancer stem cell-related genes was enhanced in 3-D culture. •CA-9 expression was enhanced, suggesting hypoxia had been induced in 3-D culture. •Drug resistance was increased. 3-D culture is useful for inducing cancer stem cells. -- Abstract: In recent years, research on resistance to chemotherapy and radiotherapy in cancer treatment has come under the spotlight, and researchers have also begun investigating the relationship between resistance and cancer stem cells. Cancer stem cells are assumed to be present inmore » esophageal cancer, but experimental methods for identification and culture of these cells have not yet been established. To solve this problem, we created spheroids using a NanoCulture® Plate (NCP) for 3-dimensional (3-D) cell culture, which was designed as a means for experimentally reproducing the 3-D structures found in the body. We investigated the potential for induction of cancer stem cells from esophageal cancer cells. Using flow cytometry we analyzed the expression of surface antigen markers CD44, CD133, CD338 (ABCG2), CD318 (CDCP1), and CD326 (EpCAM), which are known cancer stem cell markers. None of these surface antigen markers showed enhanced expression in 3-D cultured cells. We then analyzed aldehyde dehydrogenase (ALDH) enzymatic activity using the ALDEFLUOR reagent, which can identify immature cells such as stem cells and precursor cells. 3-D-cultured cells were strongly positive for ALDH enzyme activity. We also analyzed the expression of the stem cell-related genes Sox-2, Nanog, Oct3/4, and Lin28 using RT-PCR. Expression of Sox-2, Nanog, and Lin28 was enhanced. Analysis of expression of the hypoxic surface antigen marker carbonic anhydrase-9 (CA-9), which is an indicator of cancer stem cell induction and maintenance, revealed that CA-9 expression was enhanced, suggesting that hypoxia had been induced. Comparison of cancer drug resistance using cisplatin and doxorubicin in 3-D-cultured esophageal cancer cells showed that cancer drug resistance had increased. These results indicate that 3-D culture of esophageal squamous cell carcinoma lines is a useful method for inducing cancer stem cells.« less

Sodium Caseinate (CasNa) Induces Mobilization of Hematopoietic Stem Cells in a BALB/c Mouse Model

PubMed Central

Santiago-Osorio, Edelmiro; Ledesma-Martínez, Edgar; Aguiñiga-Sánchez, Itzen; Poblano-Pérez, Ignacio; Weiss-Steider, Benny; Montesinos-Montesinos, Juan José; de Lourdes Mora-García, María

2015-01-01

Background Hematopoietic stem cells transplantation has high clinical potential against a wide variety of hematologic, metabolic, and autoimmune diseases and solid tumors. Clinically, hematopoietic stem cells derived from peripheral blood are currently used more than those obtained from sources such as bone marrow. However, mobilizing agents used in the clinic tend to fail in high rates, making the number of mobilized cells insufficient for transplantation. We investigated whether sodium caseinate induces functional mobilization of hematopoietic stem cells into peripheral blood of Balb/c mice. Material/Methods Using a mouse model, we administrated sodium caseinate or Plerixafor, a commercial mobilizing agent, and analyzed counts of hematopoietic stem cells in peripheral blood, and then cells were transplanted into lethally irradiated mice to restore hematopoiesis. All assays were performed at least twice. Results We found that sodium caseinate increases the number of mononuclear cells in peripheral blood with the immunophenotype of hematopoietic stem cells (0.2 to 0.5% LSK cells), allowing them to form colonies of various cell lineages in semisolid medium (p<0.05). This effect is similar to that of Plerixafor, and cells transplanted into lethally irradiated mice can restore hematopoiesis at higher percentages than mononuclear cells mobilized by Plerixafor (40% vs. 20%, respectively). Further, a secondary transplant rescued a separate group of irradiated mice from death, proving definitive evidence of hematopoietic reconstitution after hematopoietic stem cells transplantation. Data are presented as mean ± standard deviation. To determine significant differences between the data, one-way ANOVA and the Tukey test were used. Conclusions Collectively these results show the utility of sodium caseinate as a mobilizer of hematopoietic stem cells and its potential clinical application in transplantation settings. PMID:26409928

Curcumin targets breast cancer stem-like cells with microtentacles that persist in mammospheres and promote reattachment.

PubMed

Charpentier, Monica S; Whipple, Rebecca A; Vitolo, Michele I; Boggs, Amanda E; Slovic, Jana; Thompson, Keyata N; Bhandary, Lekhana; Martin, Stuart S

2014-02-15

Cancer stem-like cells (CSC) and circulating tumor cells (CTC) have related properties associated with distant metastasis, but the mechanisms through which CSCs promote metastasis are unclear. In this study, we report that breast cancer cell lines with more stem-like properties display higher levels of microtentacles (McTN), a type of tubulin-based protrusion of the plasma cell membrane that forms on detached or suspended cells and aid in cell reattachment. We hypothesized that CSCs with large numbers of McTNs would more efficiently attach to distant tissues, promoting metastatic efficiency. The naturally occurring stem-like subpopulation of the human mammary epithelial (HMLE) cell line presents increased McTNs compared with its isogenic non-stem-like subpopulation. This increase was supported by elevated α-tubulin detyrosination and vimentin protein levels and organization. Increased McTNs in stem-like HMLEs promoted a faster initial reattachment of suspended cells that was inhibited by the tubulin-directed drug, colchicine, confirming a functional role for McTNs in stem cell reattachment. Moreover, live-cell confocal microscopy showed that McTNs persist in breast stem cell mammospheres as flexible, motile protrusions on the surface of the mammosphere. Although exposed to the environment, they also function as extensions between adjacent cells along cell-cell junctions. We found that treatment with the breast CSC-targeting compound curcumin rapidly extinguished McTN in breast CSC, preventing reattachment from suspension. Together, our results support a model in which breast CSCs with cytoskeletal alterations that promote McTNs can mediate attachment and metastasis but might be targeted by curcumin as an antimetastatic strategy. ©2013 AACR.

Curcumin targets breast cancer stem-like cells with microtentacles that persist in mammospheres and promote reattachment

PubMed Central

Charpentier, Monica S.; Whipple, Rebecca A.; Vitolo, Michele I.; Boggs, Amanda E.; Slovic, Jana; Thompson, Keyata N.; Bhandary, Lekhana; Martin, Stuart S.

2014-01-01

Cancer stem-like cells (CSC) and circulating tumor cells (CTCs) have related properties associated with distant metastasis, but the mechanisms through which CSCs promote metastasis are unclear. In this study, we report that breast cancer cell lines with more stem-like properties display higher levels of microtentacles (McTNs), a type of tubulin-based protrusion of the plasma cell membrane which forms on detached or suspended cells and aid in cell reattachment. We hypothesized that CSCs with large numbers of McTNs would more efficiently attach to distant tissues, promoting metastatic efficiency. The naturally occurring stem-like subpopulation of the HMLE breast cell line presents increased McTNs compared to its isogenic non-stem-like subpopulation. This increase was supported by elevated α-tubulin detyrosination and vimentin protein levels and organization. Increased McTNs in stem-like HMLEs promoted a faster initial reattachment of suspended cells that was inhibited by the tubulin-directed drug, colchicine, confirming a functional role for McTN in stem cell reattachment. Moreover, live cell confocal microscopy showed that McTN persist in breast stem cell mammospheres as flexible, motile protrusions on the surface of the mammosphere. While exposed to the environment, they also function as extensions between adjacent cells along cell-cell junctions. We found that treatment with the breast CSC-targeting compound curcumin rapidly extinguished McTN in breast CSC, preventing reattachment from suspension. Together, our results support a model in which breast CSCs with cytoskeletal alterations that promote McTN can mediate attachment and metastasis but might be targeted by curcumin as an anti-metastatic strategy. PMID:24371229

Human mesenchymal stem cells - current trends and future prospective

PubMed Central

Ullah, Imran; Subbarao, Raghavendra Baregundi; Rho, Gyu Jin

2015-01-01

Stem cells are cells specialized cell, capable of renewing themselves through cell division and can differentiate into multi-lineage cells. These cells are categorized as embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs) and adult stem cells. Mesenchymal stem cells (MSCs) are adult stem cells which can be isolated from human and animal sources. Human MSCs (hMSCs) are the non-haematopoietic, multipotent stem cells with the capacity to differentiate into mesodermal lineage such as osteocytes, adipocytes and chondrocytes as well ectodermal (neurocytes) and endodermal lineages (hepatocytes). MSCs express cell surface markers like cluster of differentiation (CD)29, CD44, CD73, CD90, CD105 and lack the expression of CD14, CD34, CD45 and HLA (human leucocyte antigen)-DR. hMSCs for the first time were reported in the bone marrow and till now they have been isolated from various tissues, including adipose tissue, amniotic fluid, endometrium, dental tissues, umbilical cord and Wharton's jelly which harbours potential MSCs. hMSCs have been cultured long-term in specific media without any severe abnormalities. Furthermore, MSCs have immunomodulatory features, secrete cytokines and immune-receptors which regulate the microenvironment in the host tissue. Multilineage potential, immunomodulation and secretion of anti-inflammatory molecules makes MSCs an effective tool in the treatment of chronic diseases. In the present review, we have highlighted recent research findings in the area of hMSCs sources, expression of cell surface markers, long-term in vitro culturing, in vitro differentiation potential, immunomodulatory features, its homing capacity, banking and cryopreservation, its application in the treatment of chronic diseases and its use in clinical trials. PMID:25797907

Glycyrrhizic acid attenuates stem cell-like phenotypes of human dermal papilla cells.

PubMed

Kiratipaiboon, Chayanin; Tengamnuay, Parkpoom; Chanvorachote, Pithi

2015-12-15

Although the growth of unwanted hair or hirsutism is a harmless condition, many people find it bothersome and embarrassing. Maintaining stem cell features of dermal papilla cells is a critical biological process that keeps the high rate of hair growth. Glycyrrhizic acid has been reported to impair hair growth in some studies; however, its underlying mechanism has not yet been investigated. This study aimed to explore the effect and underlying mechanism of glycyrrhizic acid on stemness of human dermal papilla cells. The stem cell molecular markers, epithelial to mesenchymal markers and Wnt/β-catenin-associated proteins of human dermal papilla cell line and primary human dermal papilla cells were analysed by western blot analysis and immunocytochemistry. The present study demonstrated that glycyrrhizic acid significantly depressed the stemness of dermal papilla cells in dose- and time-dependent manners. Clonogenicity and stem cell markers in the glycyrrhizic acid-treated cells were found to gradually decrease in the culture in a time-dependent manner. Our results demonstrated that glycyrrhizic acid exerted the stem cell suppressing effects through the interruption of ATP-dependent tyrosine kinase/glycogen synthase kinase3β-dependent mechanism which in turn down-regulated the β-catenin signalling pathway, coupled with decreased its down-stream epithelial-mesenchymal transition and self-renewal transcription factors, namely, Oct-4, Nanog, Sox2, ZEB1 and Snail. The effect of glycyrrhizic acid on the reduction of stem cell features was also observed in the primary dermal papilla cells directly obtained from human hair follicles. These results revealed a novel molecular mechanism of glycyrrhizic acid in regulation of dermal papilla cells and provided the evidence supporting the use of this compound in suppressing the growth of unwanted hair. Copyright © 2015 Elsevier GmbH. All rights reserved.

Sodium Caseinate (CasNa) Induces Mobilization of Hematopoietic Stem Cells in a BALB/c Mouse Model.

PubMed

Santiago-Osorio, Edelmiro; Ledesma-Martínez, Edgar; Aguiñiga-Sánchez, Itzen; Poblano-Pérez, Ignacio; Weiss-Steider, Benny; Montesinos-Montesinos, Juan José; Mora-García, María de Lourdes

2015-09-25

BACKGROUND Hematopoietic stem cells transplantation has high clinical potential against a wide variety of hematologic, metabolic, and autoimmune diseases and solid tumors. Clinically, hematopoietic stem cells derived from peripheral blood are currently used more than those obtained from sources such as bone marrow. However, mobilizing agents used in the clinic tend to fail in high rates, making the number of mobilized cells insufficient for transplantation. We investigated whether sodium caseinate induces functional mobilization of hematopoietic stem cells into peripheral blood of Balb/c mice. MATERIAL AND METHODS Using a mouse model, we administrated sodium caseinate or Plerixafor, a commercial mobilizing agent, and analyzed counts of hematopoietic stem cells in peripheral blood, and then cells were transplanted into lethally irradiated mice to restore hematopoiesis. All assays were performed at least twice. RESULTS We found that sodium caseinate increases the number of mononuclear cells in peripheral blood with the immunophenotype of hematopoietic stem cells (0.2 to 0.5% LSK cells), allowing them to form colonies of various cell lineages in semisolid medium (p<0.05). This effect is similar to that of Plerixafor, and cells transplanted into lethally irradiated mice can restore hematopoiesis at higher percentages than mononuclear cells mobilized by Plerixafor (40% vs. 20%, respectively). Further, a secondary transplant rescued a separate group of irradiated mice from death, proving definitive evidence of hematopoietic reconstitution after hematopoietic stem cells transplantation. Data are presented as mean ± standard deviation. To determine significant differences between the data, one-way ANOVA and the Tukey test were used. CONCLUSIONS Collectively these results show the utility of sodium caseinate as a mobilizer of hematopoietic stem cells and its potential clinical application in transplantation settings.

A home away from home: challenges and opportunities in engineering in vitro muscle satellite cell niches

PubMed Central

Cosgrove, Benjamin D.; Sacco, Alessandra; Gilbert, Penney M.; Blau, Helen M.

2009-01-01

Satellite cells are skeletal muscle stem cells with a principal role in postnatal skeletal muscle regeneration. Satellite cells, like many tissue-specific adult stem cells, reside in a quiescent state in an instructive, anatomically defined niche. The satellite cell niche constitutes a distinct membrane-enclosed compartment within the muscle fiber, containing a diversity of biochemical and biophysical signals that influence satellite cell function. A major limitation to the study and clinical utility of satellite cells is that upon removal from the muscle fiber and plating in traditional plastic tissue culture platforms, their muscle stem cell properties are rapidly lost. Clearly, the maintenance of stem cell function is critically dependent on in vivo niche signals, highlighting the need to create novel in vitro microenvironments that allow for the maintenance and propagation of satellite cells while retaining their potential to function as muscle stem cells. Here, we discuss how emerging biomaterials technologies offer great promise for engineering in vitro microenvironments to meet these challenges. In engineered biomaterials, signaling molecules can be presented in a manner that more closely mimics cell-cell and cell-matrix interactions and matrices can be fabricated with diverse rigidities that approximate in vivo tissues. The development of in vitro microenvironments in which niche features can be systematically modulated will be instrumental not only to future insights into muscle stem cell biology and therapeutic approaches to muscle diseases and muscle wasting with aging, but also will provide a paradigm for the analysis of numerous adult tissue-specific stem cells. PMID:19751902

Characterization and genetic manipulation of human umbilical cord vein mesenchymal stem cells: potential application in cell-based gene therapy.

PubMed

Kermani, Abbas Jafari; Fathi, Fardin; Mowla, Seyed Javad

2008-04-01

Stem cells are defined by two main characteristics: self-renewal capacity and commitment to multi-lineage differentiation. The cells have a great therapeutic potential in repopulating damaged tissues as well as being genetically manipulated and used in cell-based gene therapy. Umbilical cord vein is a readily available and inexpensive source of stem cells that are capable of generating various cell types. Despite the recent isolation of human umbilical cord vein mesenchymal stem cells (UVMSC), the self-renewal capacity and the potential clinical application of the cells are not well known. In the present study, we have successfully isolated and cultured human UVMSCs. Our data further revealed that the isolated cells express the self-renewal genes Oct-4, Nanog, ZFX, Bmi-1, and Nucleostemin; but not Zic-3, Hoxb-4, TCL-1, Tbx-3 and Esrrb. In addition, our immunocytochemistry results revealed the expression of SSEA-4, but not SSEA-3, TRA-1-60, and TRA-1-81 embryonic stem cell surface markers in the cells. Also, we were able to transfect the cells with a reporter, enhanced green fluorescent protein (EGFP), and a therapeutic human brain-derived neurotrophic factor (hBDNF) gene by means of electroporation and obtained a stable cell line, which could constantly express both transgenes. The latter data provide further evidence on the usefulness of umbilical cord vein mesenchymal stem cells as a readily available source of stem cells, which could be genetically manipulated and used in cell-based gene therapy applications.

Current Therapeutic Strategies for Stem Cell-Based Cartilage Regeneration

PubMed Central

Nam, Yoojun; Lee, Jennifer

2018-01-01

The process of cartilage destruction in the diarthrodial joint is progressive and irreversible. This destruction is extremely difficult to manage and frustrates researchers, clinicians, and patients. Patients often take medication to control their pain. Surgery is usually performed when pain becomes uncontrollable or joint function completely fails. There is an unmet clinical need for a regenerative strategy to treat cartilage defect without surgery due to the lack of a suitable regenerative strategy. Clinicians and scientists have tried to address this using stem cells, which have a regenerative potential in various tissues. Cartilage may be an ideal target for stem cell treatment because it has a notoriously poor regenerative potential. In this review, we describe past, present, and future strategies to regenerate cartilage in patients. Specifically, this review compares a surgical regenerative technique (microfracture) and cell therapy, cell therapy with and without a scaffold, and therapy with nonaggregated and aggregated cells. We also review the chondrogenic potential of cells according to their origin, including autologous chondrocytes, mesenchymal stem cells, and induced pluripotent stem cells. PMID:29765426

Therapeutic Effects of Human Amniotic Fluid-Derived Stem Cells on Renal Interstitial Fibrosis in a Murine Model of Unilateral Ureteral Obstruction

PubMed Central

Yin, Zhongcheng; Zhou, Xudong; Li, Xiaoju; Xiao, Aiguo

2013-01-01

Interstitial fibrosis is regarded as the main pathway for the progression of chronic kidney disease (CKD) and is often associated with severe renal dysfunction. Stem cell-based therapies may provide alternative approaches for the treatment of CKD. Human amniotic fluid-derived stem cells (hAFSCs) are a novel stem cell population, which exhibit both embryonic and mesenchymal stem cell characteristics. Herein, the present study investigated whether the transplantation of hAFSCs into renal tissues could improve renal interstitial fibrosis in a murine model of unilateral ureteral obstruction (UUO). We showed that hAFSCs provided a protective effect and alleviated interstitial fibrosis as reflected by an increase in microvascular density; additionally, hAFSCs treatment beneficially modulated protein levels of vascular endothelial growth factor (VEGF), hypoxia inducible factor-1α (HIF-1α) and transforming growth factor-β1 (TGF-β1). Therefore, we hypothesize that hAFSCs could represent an alternative, readily available source of stem cells that can be applied for the treatment of renal interstitial fibrosis. PMID:23724119

Cancer stemness and metastatic potential of the novel tumor cell line K3: an inner mutated cell of bone marrow-derived mesenchymal stem cells.

PubMed

Qian, Hui; Ding, Xiaoqing; Zhang, Jiao; Mao, Fei; Sun, Zixuan; Jia, Haoyuan; Yin, Lei; Wang, Mei; Zhang, Xu; Zhang, Bin; Yan, Yongmin; Zhu, Wei; Xu, Wenrong

2017-06-13

Mesenchymal stem cells (MSCs) transplantation has been used for therapeutic applications in various diseases. Here we report MSCs can malignantly transform in vivo. The novel neoplasm was found on the tail of female rat after injection with male rat bone marrow-derived MSCs (rBM-MSCs) and the new tumor cell line, K3, was isolated from the neoplasm. The K3 cells expressed surface antigens and pluripotent genes similar to those of rBM-MSCs and presented tumor cell features. Moreover, the K3 cells contained side population cells (SP) like cancer stem cells (CSCs), which might contribute to K3 heterogeneity and tumorigenic capacity. To investigate the metastatic potential of K3 cells, we established the nude mouse models of liver and lung metastases and isolated the corresponding metastatic cell lines K3-F4 and K3-B6. Both K3-F4 and K3-B6 cell lines with higher metastatic potential acquired more mesenchymal and stemness-related features. Epithelial-mesenchymal transition is a potential mechanism of K3-F4 and K3-B6 formation.

Hymyc1 downregulation promotes stem cell proliferation in Hydra vulgaris.

PubMed

Ambrosone, Alfredo; Marchesano, Valentina; Tino, Angela; Hobmayer, Bert; Tortiglione, Claudia

2012-01-01

Hydra is a unique model for studying the mechanisms underlying stem cell biology. The activity of the three stem cell lineages structuring its body constantly replenishes mature cells lost due to normal tissue turnover. By a poorly understood mechanism, stem cells are maintained through self-renewal while concomitantly producing differentiated progeny. In vertebrates, one of many genes that participate in regulating stem cell homeostasis is the protooncogene c-myc, which has been recently identified also in Hydra, and found expressed in the interstitial stem cell lineage. In the present paper, by developing a novel strategy of RNA interference-mediated gene silencing (RNAi) based on an enhanced uptake of small interfering RNAi (siRNA), we provide molecular and biological evidence for an unexpected function of the Hydra myc gene (Hymyc1) in the homeostasis of the interstitial stem cell lineage. We found that Hymyc1 inhibition impairs the balance between stem cell self renewal/differentiation, as shown by the accumulation of stem cell intermediate and terminal differentiation products in genetically interfered animals. The identical phenotype induced by the 10058-F4 inhibitor, a disruptor of c-Myc/Max dimerization, demonstrates the specificity of the RNAi approach. We show the kinetic and the reversible feature of Hymyc1 RNAi, together with the effects displayed on regenerating animals. Our results show the involvement of Hymyc1 in the control of interstitial stem cell dynamics, provide new clues to decipher the molecular control of the cell and tissue plasticity in Hydra, and also provide further insights into the complex myc network in higher organisms. The ability of Hydra cells to uptake double stranded RNA and to trigger a RNAi response lays the foundations of a comprehensive analysis of the RNAi response in Hydra allowing us to track back in the evolution and the origin of this process.

Hymyc1 Downregulation Promotes Stem Cell Proliferation in Hydra vulgaris

PubMed Central

Ambrosone, Alfredo; Marchesano, Valentina; Tino, Angela; Hobmayer, Bert; Tortiglione, Claudia

2012-01-01

Hydra is a unique model for studying the mechanisms underlying stem cell biology. The activity of the three stem cell lineages structuring its body constantly replenishes mature cells lost due to normal tissue turnover. By a poorly understood mechanism, stem cells are maintained through self-renewal while concomitantly producing differentiated progeny. In vertebrates, one of many genes that participate in regulating stem cell homeostasis is the protooncogene c-myc, which has been recently identified also in Hydra, and found expressed in the interstitial stem cell lineage. In the present paper, by developing a novel strategy of RNA interference-mediated gene silencing (RNAi) based on an enhanced uptake of small interfering RNAi (siRNA), we provide molecular and biological evidence for an unexpected function of the Hydra myc gene (Hymyc1) in the homeostasis of the interstitial stem cell lineage. We found that Hymyc1 inhibition impairs the balance between stem cell self renewal/differentiation, as shown by the accumulation of stem cell intermediate and terminal differentiation products in genetically interfered animals. The identical phenotype induced by the 10058-F4 inhibitor, a disruptor of c-Myc/Max dimerization, demonstrates the specificity of the RNAi approach. We show the kinetic and the reversible feature of Hymyc1 RNAi, together with the effects displayed on regenerating animals. Our results show the involvement of Hymyc1 in the control of interstitial stem cell dynamics, provide new clues to decipher the molecular control of the cell and tissue plasticity in Hydra, and also provide further insights into the complex myc network in higher organisms. The ability of Hydra cells to uptake double stranded RNA and to trigger a RNAi response lays the foundations of a comprehensive analysis of the RNAi response in Hydra allowing us to track back in the evolution and the origin of this process. PMID:22292012

Anti-Inflammatory Effects of Adult Stem Cells in Sustained Lung Injury: A Comparative Study

PubMed Central

Moodley, Yuben; Vaghjiani, Vijesh; Chan, James; Baltic, Svetlana; Ryan, Marisa; Tchongue, Jorge; Samuel, Chrishan S.; Murthi, Padma; Parolini, Ornella; Manuelpillai, Ursula

2013-01-01

Lung diseases are a major cause of global morbidity and mortality that are treated with limited efficacy. Recently stem cell therapies have been shown to effectively treat animal models of lung disease. However, there are limitations to the translation of these cell therapies to clinical disease. Studies have shown that delayed treatment of animal models does not improve outcomes and that the models do not reflect the repeated injury that is present in most lung diseases. We tested the efficacy of amnion mesenchymal stem cells (AM-MSC), bone marrow MSC (BM-MSC) and human amniotic epithelial cells (hAEC) in C57BL/6 mice using a repeat dose bleomycin-induced model of lung injury that better reflects the repeat injury seen in lung diseases. The dual bleomycin dose led to significantly higher levels of inflammation and fibrosis in the mouse lung compared to a single bleomycin dose. Intravenously infused stem cells were present in the lung in similar numbers at days 7 and 21 post cell injection. In addition, stem cell injection resulted in a significant decrease in inflammatory cell infiltrate and a reduction in IL-1 (AM-MSC), IL-6 (AM-MSC, BM-MSC, hAEC) and TNF-α (AM-MSC). The only trophic factor tested that increased following stem cell injection was IL-1RA (AM-MSC). IL-1RA levels may be modulated by GM-CSF produced by AM-MSC. Furthermore, only AM-MSC reduced collagen deposition and increased MMP-9 activity in the lung although there was a reduction of the pro-fibrogenic cytokine TGF-β following BM-MSC, AM-MSC and hAEC treatment. Therefore, AM-MSC may be more effective in reducing injury following delayed injection in the setting of repeated lung injury. PMID:23936322

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.

Transcriptional Analysis of Fracture Healing and the Induction of Embryonic Stem Cell–Related Genes

PubMed Central

Bais, Manish; McLean, Jody; Sebastiani, Paola; Young, Megan; Wigner, Nathan; Smith, Temple; Kotton, Darrell N.; Einhorn, Thomas A.; Gerstenfeld, Louis C.

2009-01-01

Fractures are among the most common human traumas. Fracture healing represents a unique temporarily definable post-natal process in which to study the complex interactions of multiple molecular events that regulate endochondral skeletal tissue formation. Because of the regenerative nature of fracture healing, it is hypothesized that large numbers of post-natal stem cells are recruited and contribute to formation of the multiple cell lineages that contribute to this process. Bayesian modeling was used to generate the temporal profiles of the transcriptome during fracture healing. The temporal relationships between ontologies that are associated with various biologic, metabolic, and regulatory pathways were identified and related to developmental processes associated with skeletogenesis, vasculogenesis, and neurogenesis. The complement of all the expressed BMPs, Wnts, FGFs, and their receptors were related to the subsets of transcription factors that were concurrently expressed during fracture healing. We further defined during fracture healing the temporal patterns of expression for 174 of the 193 genes known to be associated with human genetic skeletal disorders. In order to identify the common regulatory features that might be present in stem cells that are recruited during fracture healing to other types of stem cells, we queried the transcriptome of fracture healing against that seen in embryonic stem cells (ESCs) and mesenchymal stem cells (MSCs). Approximately 300 known genes that are preferentially expressed in ESCs and ∼350 of the known genes that are preferentially expressed in MSCs showed induction during fracture healing. Nanog, one of the central epigenetic regulators associated with ESC stem cell maintenance, was shown to be associated in multiple forms or bone repair as well as MSC differentiation. In summary, these data present the first temporal analysis of the transcriptome of an endochondral bone formation process that takes place during fracture healing. They show that neurogenesis as well as vasculogenesis are predominant components of skeletal tissue formation and suggest common pathways are shared between post-natal stem cells and those seen in ESCs. PMID:19415118

Single Lgr5- or Lgr6-expressing taste stem/progenitor cells generate taste bud cells ex vivo

PubMed Central

Ren, Wenwen; Lewandowski, Brian C.; Watson, Jaime; Aihara, Eitaro; Iwatsuki, Ken; Bachmanov, Alexander A.; Margolskee, Robert F.; Jiang, Peihua

2014-01-01

Leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5) and its homologs (e.g., Lgr6) mark adult stem cells in multiple tissues. Recently, we and others have shown that Lgr5 marks adult taste stem/progenitor cells in posterior tongue. However, the regenerative potential of Lgr5-expressing (Lgr5+) cells and the identity of adult taste stem/progenitor cells that regenerate taste tissue in anterior tongue remain elusive. In the present work, we describe a culture system in which single isolated Lgr5+ or Lgr6+ cells from taste tissue can generate continuously expanding 3D structures (“organoids”). Many cells within these taste organoids were cycling and positive for proliferative cell markers, cytokeratin K5 and Sox2, and incorporated 5-bromo-2’-deoxyuridine. Importantly, mature taste receptor cells that express gustducin, carbonic anhydrase 4, taste receptor type 1 member 3, nucleoside triphosphate diphosphohydrolase-2, or cytokeratin K8 were present in the taste organoids. Using calcium imaging assays, we found that cells grown out from taste organoids derived from isolated Lgr5+ cells were functional and responded to tastants in a dose-dependent manner. Genetic lineage tracing showed that Lgr6+ cells gave rise to taste bud cells in taste papillae in both anterior and posterior tongue. RT-PCR data demonstrated that Lgr5 and Lgr6 may mark the same subset of taste stem/progenitor cells both anteriorly and posteriorly. Together, our data demonstrate that functional taste cells can be generated ex vivo from single Lgr5+ or Lgr6+ cells, validating the use of this model for the study of taste cell generation. PMID:25368147

Single Lgr5- or Lgr6-expressing taste stem/progenitor cells generate taste bud cells ex vivo.

PubMed

Ren, Wenwen; Lewandowski, Brian C; Watson, Jaime; Aihara, Eitaro; Iwatsuki, Ken; Bachmanov, Alexander A; Margolskee, Robert F; Jiang, Peihua

2014-11-18

Leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5) and its homologs (e.g., Lgr6) mark adult stem cells in multiple tissues. Recently, we and others have shown that Lgr5 marks adult taste stem/progenitor cells in posterior tongue. However, the regenerative potential of Lgr5-expressing (Lgr5(+)) cells and the identity of adult taste stem/progenitor cells that regenerate taste tissue in anterior tongue remain elusive. In the present work, we describe a culture system in which single isolated Lgr5(+) or Lgr6(+) cells from taste tissue can generate continuously expanding 3D structures ("organoids"). Many cells within these taste organoids were cycling and positive for proliferative cell markers, cytokeratin K5 and Sox2, and incorporated 5-bromo-2'-deoxyuridine. Importantly, mature taste receptor cells that express gustducin, carbonic anhydrase 4, taste receptor type 1 member 3, nucleoside triphosphate diphosphohydrolase-2, or cytokeratin K8 were present in the taste organoids. Using calcium imaging assays, we found that cells grown out from taste organoids derived from isolated Lgr5(+) cells were functional and responded to tastants in a dose-dependent manner. Genetic lineage tracing showed that Lgr6(+) cells gave rise to taste bud cells in taste papillae in both anterior and posterior tongue. RT-PCR data demonstrated that Lgr5 and Lgr6 may mark the same subset of taste stem/progenitor cells both anteriorly and posteriorly. Together, our data demonstrate that functional taste cells can be generated ex vivo from single Lgr5(+) or Lgr6(+) cells, validating the use of this model for the study of taste cell generation.

CD146 Expression Influences Periapical Cyst Mesenchymal Stem Cell Properties.

PubMed

Paduano, Francesco; Marrelli, Massimo; Palmieri, Francesca; Tatullo, Marco

2016-10-01

Recent studies have identified a new human dental derived progenitor cell population with multi-lineage differentiation potential referred to as human periapical cyst mesenchymal stem cells (hPCy-MSCs). In the present study, we compared two subpopulations of hPCy-MSCs characterised by the low or high expression of CD146 to establish whether this expression can regulate their stem cell properties. Using flow cytometry, we evaluated the stem cell marker profile of hPCy-MSCs during passaging. Furthermore, CD146 Low and CD146 High cells were sorted by magnetic beads and subsequently both cell populations were evaluated for differences in their proliferation, self-renewal, stem cell surface markers, stemness genes expression and osteogenic differentiation potential.We found that hPCy-MSCs possessed a stable expression of several mesenchymal stem cell surface markers, whereas CD146 expression declined during passaging.In addition, sorted CD146 Low cells proliferated significantly faster, displayed higher colony-forming unit-fibroblast capacity and showed higher expression of Klf4 when compared to the CD146 High subset. Significantly, the osteogenic potential of hPCy-MSCs was greater in the CD146 Low than in CD146 High population. These results demonstrate that CD146 is spontaneously downregulated with passaging at both mRNA and protein levels and that the high expression of CD146 reduces the proliferative, self-renewal and osteogenic differentiation potential of hPCy-MSCs. In conclusion, our study demonstrates that changes in the expression of CD146 can influence the stem cell properties of hPCy-MSCs.

A reserve stem cell population in small intestine renders Lgr5-positive cells dispensable

PubMed Central

Tian, Hua; Biehs, Brian; Warming, Soren; Leong, Kevin G.; Rangell, Linda; Klein, Ophir D.; de Sauvage, Frederic J.

2014-01-01

The small intestine epithelium renews every 2 to 5 days, making it one of the most regenerative mammalian tissues. Genetic inducible fate mapping studies have identified two principal epithelial stem cell pools in this tissue. One pool consists of columnar Lgr5-expressing cells that cycle rapidly and are present predominantly at the crypt base1. The other pool consists of Bmi1-expressing cells that largely reside above the crypt base2. However, the relative functions of these two pools and their interrelationship are not understood. Here, we specifically ablated Lgr5-expressing cells using a diphtheria toxin receptor (DTR) gene knocked into the Lgr5 locus. We found that complete loss of the Lgr5-expressing cells did not perturb homeostasis of the epithelium, indicating that other cell types can compensate for elimination of this population. After ablation of Lgr5-expressing cells, progeny production by Bmi1-expressing cells increased, suggesting that Bmi1-expressing stem cells compensate for the loss of Lgr5-expressing cells. Indeed, lineage tracing showed that Bmi1-expressing cells gave rise to Lgr5-expressing cells, pointing to a hierarchy of stem cells in the intestinal epithelium. Our results demonstrate that Lgr5-expressing cells are dispensable for normal intestinal homeostasis. In the absence of these cells, the Bmi1-expressing cells can serve as an alternative stem cell pool, providing the first experimental evidence for the interrelationship between these populations. The Bmi1-expressing stem cells may represent both a reserve stem cell pool in case of injury to the small intestine epithelium and a source for replenishment of the Lgr5-expressing cells under non-pathological conditions. PMID:21927002

Differentiation of Bovine Spermatogonial Stem Cells into Osteoblasts

PubMed Central

Qasemi-Panahi, Babak; Tajik, Parviz; Movahedin, Mansoureh; Moghaddam, Gholamali; Barzgar, Younes; Heidari-Vala, Hamed

2011-01-01

Spermatogonial Stem Cell (SSC) technologies provide multiple opportunities for research in the field of biotechnology and regenerative medicine. The therapeutic use of Embryonic Stem Cells (ESCs) is restricted due to severe ethical and immunological concerns. Therefore, we need a new pluripotent cell type. Despite well-known role of germ cells in the gametogenesis, some facts apparently show their multipotentiality. In the present study, bovine SSCs were co-cultured with Sertoli cell for 7 days. Sertoli cells and SSCs were identified by Vimentin and Oct-4 immunocytochemical staining method, respectively. In order to differentiate SSCs into osteoblasts, we used consecutive inducer media without separation of the colonies. We characterized osteoblasts using Alizarin red staining. PMID:23408761

Differentiation of bovine spermatogonial stem cells into osteoblasts.

PubMed

Qasemi-Panahi, Babak; Tajik, Parviz; Movahedin, Mansoureh; Moghaddam, Gholamali; Barzgar, Younes; Heidari-Vala, Hamed

2011-07-01

Spermatogonial Stem Cell (SSC) technologies provide multiple opportunities for research in the field of biotechnology and regenerative medicine. The therapeutic use of Embryonic Stem Cells (ESCs) is restricted due to severe ethical and immunological concerns. Therefore, we need a new pluripotent cell type. Despite well-known role of germ cells in the gametogenesis, some facts apparently show their multipotentiality. In the present study, bovine SSCs were co-cultured with Sertoli cell for 7 days. Sertoli cells and SSCs were identified by Vimentin and Oct-4 immunocytochemical staining method, respectively. In order to differentiate SSCs into osteoblasts, we used consecutive inducer media without separation of the colonies. We characterized osteoblasts using Alizarin red staining.

Vectorization of ultrasound-responsive nanoparticles in placental mesenchymal stem cells for cancer therapy.

PubMed

Paris, Juan L; de la Torre, Paz; Victoria Cabañas, M; Manzano, Miguel; Grau, Montserrat; Flores, Ana I; Vallet-Regí, María

2017-05-04

A new platform constituted by engineered responsive nanoparticles transported by human mesenchymal stem cells is here presented as a proof of concept. Ultrasound-responsive mesoporous silica nanoparticles are coated with polyethylenimine to favor their effective uptake by decidua-derived mesenchymal stem cells. The responsive-release ability of the designed nanoparticles is confirmed, both in vial and in vivo. In addition, this capability is maintained inside the cells used as carriers. The migration capacity of the nanoparticle-cell platform towards mammary tumors is assessed in vitro. The efficacy of this platform for anticancer therapy is shown against mammary tumor cells by inducing the release of doxorubicin only when the cell vehicles are exposed to ultrasound.

Comparative evaluation of the isolation and quantification of stem cells derived from dental pulp and periodontal ligament of a permanent tooth and to assess their viability and proliferation on a platelet-rich fibrin scaffold

PubMed Central

Khurana, Rohit; Kudva, Praveen Bhasker; Husain, Syed Yawer

2017-01-01

Background: The present study aims to comparatively evaluate the isolation and quantification of stem cells derived from dental pulp and periodontal ligament of a permanent tooth and to assess their viability and proliferation on a platelet-rich fibrin (PRF) scaffold. Materials and Methods: A total of 15 systemically healthy individuals between the age group of 15–25 years requiring third molar or orthodontic premolar extractions. Teeth were extracted atraumatically and transported to the laboratory. Stem cells were isolated from dental pulp and periodontal ligament. After attaining more than 90% confluency by the 7th day, these cells were tested for their viability and characterization. Stem cells were also incubated with PRF and viability was assessed on the 7th day. Results: The mean number of cell for dental pulp stem cells (DPSCs) and periodontal ligament stem cell (PDLSC) was statistically insignificant (P > 0.05). The mean live cell viability was compared between DPSC (98.07%) and PDLSC (98%). Both DPSC and PDLSC showed a high percentage of expression of CD73 markers, 30.40% and 29.80%, respectively. However, DPSCs and PDLSCs lacked expression of CD34 expressing only 3.47% and 3.53%, respectively. PRF membrane as a scaffold exhibited no cytotoxic effects on DPCS's or PDLSC's. The cell viability of cells cultured with PRF was statistically insignificant (P > 0.05) when compared to the cells cultured with culture media. Conclusion: The study thus indicates that dental pulp and periodontal ligament are both rich sources of mesenchymal stem cells and can be successfully used for obtaining stem cells. PRF exhibits no cytotoxic effects on the cells and can be used in conjunction with dental stem cells. PMID:29386795

Identification of Multipotent Stem Cells in Human Brain Tissue Following Stroke.

PubMed

Tatebayashi, Kotaro; Tanaka, Yasue; Nakano-Doi, Akiko; Sakuma, Rika; Kamachi, Saeko; Shirakawa, Manabu; Uchida, Kazutaka; Kageyama, Hiroto; Takagi, Toshinori; Yoshimura, Shinichi; Matsuyama, Tomohiro; Nakagomi, Takayuki

2017-06-01

Perivascular regions of the brain harbor multipotent stem cells. We previously demonstrated that brain pericytes near blood vessels also develop multipotency following experimental ischemia in mice and these ischemia-induced multipotent stem cells (iSCs) can contribute to neurogenesis. However, it is essential to understand the traits of iSCs in the poststroke human brain for possible applications in stem cell-based therapies for stroke patients. In this study, we report for the first time that iSCs can be isolated from the poststroke human brain. Putative iSCs were derived from poststroke brain tissue obtained from elderly stroke patients requiring decompressive craniectomy and partial lobectomy for diffuse cerebral infarction. Immunohistochemistry showed that these iSCs were localized near blood vessels within poststroke areas containing apoptotic/necrotic neurons and expressed both the stem cell marker nestin and several pericytic markers. Isolated iSCs expressed these same markers and demonstrated high proliferative potential without loss of stemness. Furthermore, isolated iSCs expressed other stem cell markers, such as Sox2, c-myc, and Klf4, and differentiated into multiple cells in vitro, including neurons. These results show that iSCs, which are likely brain pericyte derivatives, are present within the poststroke human brain. This study suggests that iSCs can contribute to neural repair in patients with stroke.

Biochemical properties of a keratan sulphate/chondroitin sulphate proteoglycan expressed in primate pluripotent stem cells*

PubMed Central

Cooper, Susan; Bennett, William; Andrade, Jessica; Reubinoff, Benjamin E; Thomson, James; Pera, Martin F

2002-01-01

We previously identified a pericellular matrix keratan sulphate/chondroitin sulphate proteoglycan present on the surface of human embryonal carcinoma stem cells, cells whose differentiation mimics early development. Antibodies reactive with various epitopes on this molecule define a cluster of differentiation markers for primate pluripotent stem cells. We describe the purification of a form of this molecule which is secreted or shed into the culture medium. Biochemical analysis of the secreted form of this molecule shows that the monomeric form, whilst containing keratan sulphate, resembles mucins in its structure and its modification with O-linked carbohydrate. Immunofluorescence and immunoblotting data show that monkey and human pluripotent stem cells react with antibodies directed against epitopes on either carbohydrate side chains or the protein core of the molecule. PMID:12033730

[THE USE AND STORAGE OF STEM CELLS AND CORD BLOOD: FRENCH AND ENGLISH LAW COMPARATIVE APPROACH].

PubMed

Madanamoothoo, Allane

2015-07-01

Becoming parents is one of the greatest wishes of a lot of couples. When their dreams come true, prior to the birth of the child, parents have to face several points: the choice of the name, place of delivery, breast or bottle feeding, etc. Recently, they have to face the issues of cord blood stem cells. Researchers and cord blood banks are also interested in those cells. In many countries a lot of advertising is made around umbilical cord blood stem cells. In France as in England, the use and preservation of cord blood are regulated by the legislators without necessarily having the same approach. The objective of this paper is to present English and French law approaches' on cord blood stem cells.

Neuronal differentiation of stem cells isolated from adult muscle.

PubMed

Romero-Ramos, Marina; Vourc'h, Patrick; Young, Henry E; Lucas, Paul A; Wu, Young; Chivatakarn, Onanong; Zaman, Rumina; Dunkelman, Noushin; el-Kalay, Mohammad A; Chesselet, Marie-Françoise

2002-09-15

Lineage uncommitted pluripotent stem cells reside in the connective tissue of skeletal muscle. The present study was carried out with pluripotent stem cells (PPSCs) isolated from 6-month old rat muscle. Before differentiation, these cells were vimentin+, CD90+, CD45-, and varied in their expression of CD34. The PPSCs were expanded as non-adherent aggregates under similar conditions to those used to generate neurospheres from embryonic or neural stem cells. The PPSC-derived neurospheres were positive for nestin, an early marker present in neuronal precursors, and expressed the two alternative mRNA forms of the neuroectodermal marker Pax-6, as well as mRNA for Oct-4, a gene related to the pluripotentiality of stem cells. To confirm their neural potential, PPSC-derived neurospheres were plated on coated coverslips under varying conditions: Neurobasal medium with N2 or B27, and either NT3 or BDNF. After 4-6 days the cells expressed neuronal (Tuj1+, NF68), astrocytic (GFAP) and oligodendrocytic (MOSP+, MBP+) markers, both by immunocytochemistry and RT-PCR. In addition, PPSCs were cultured as monolayers under adherent conditions, exposed to growth factors and defined differentiating conditions for 5 hr, and subsequently kept for 2 days in a maturation medium. At this point they gave rise to a mixed population of early neural progenitors (Nestin+ or NG2+), immature and mature neurons (Tuj1+ and NF145+) and myelin producing oligodendrocytes (CNPase + and MOSP+). Our study shows that PPSCs present in adult muscle can overcome germ lineage restrictions and express the molecular characteristics of brain cells. Therefore, PPSCs isolated from adult muscle could provide a novel source for autologous cell replacement in neurodegenerative and demyelinating diseases. Copyright 2002 Wiley-Liss, Inc.

Contributions of Bioactive Molecules in Stem Cell-Based Periodontal Regeneration

PubMed Central

Liu, An-Qi; Hu, Cheng-Hu; Jin, Fang; Zhang, Li-Shu; Xuan, Kun

2018-01-01

Periodontal disease is a widespread disease, which without proper treatment, may lead to tooth loss in adults. Because stem cells from the inflammatory microenvironment created by periodontal disease exhibit impaired regeneration potential even under favorable conditions, it is difficult to obtain satisfactory therapeutic outcomes using traditional treatments, which only focus on the control of inflammation. Therefore, a new stem cell-based therapy known as cell aggregates/cell sheets technology has emerged. This approach provides sufficient numbers of stem cells with high viability for treating the defective site and offers new hope in the field of periodontal regeneration. However, it is not sufficient for regenerating periodontal tissues by delivering cell aggregates/cell sheets to the impaired microenvironment in order to suppress the function of resident cells. In the present review, we summarize some promising bioactive molecules that act as cellular signals, which recreate a favorable microenvironment for tissue regeneration, recruit endogenous cells into the defective site and enhance the viability of exogenous cells. PMID:29597317

Modelling IRF8 Deficient Human Hematopoiesis and Dendritic Cell Development with Engineered iPS Cells.

PubMed

Sontag, Stephanie; Förster, Malrun; Qin, Jie; Wanek, Paul; Mitzka, Saskia; Schüler, Herdit M; Koschmieder, Steffen; Rose-John, Stefan; Seré, Kristin; Zenke, Martin

2017-04-01

Human induced pluripotent stem (iPS) cells can differentiate into cells of all three germ layers, including hematopoietic stem cells and their progeny. Interferon regulatory factor 8 (IRF8) is a transcription factor, which acts in hematopoiesis as lineage determining factor for myeloid cells, including dendritic cells (DC). Autosomal recessive or dominant IRF8 mutations occurring in patients cause severe monocytic and DC immunodeficiency. To study IRF8 in human hematopoiesis we generated human IRF8-/- iPS cells and IRF8-/- embryonic stem (ES) cells using RNA guided CRISPR/Cas9n genome editing. Upon induction of hematopoietic differentiation, we demonstrate that IRF8 is dispensable for iPS cell and ES cell differentiation into hemogenic endothelium and for endothelial-to-hematopoietic transition, and thus development of hematopoietic progenitors. We differentiated iPS cell and ES cell derived progenitors into CD141+ cross-presenting cDC1 and CD1c+ classical cDC2 and CD303+ plasmacytoid DC (pDC). We found that IRF8 deficiency compromised cDC1 and pDC development, while cDC2 development was largely unaffected. Additionally, in an unrestricted differentiation regimen, IRF8-/- iPS cells and ES cells exhibited a clear bias toward granulocytes at the expense of monocytes. IRF8-/- DC showed reduced MHC class II expression and were impaired in cytokine responses, migration, and antigen presentation. Taken together, we engineered a human IRF8 knockout model that allows studying molecular mechanisms of human immunodeficiencies in vitro, including the pathophysiology of IRF8 deficient DC. Stem Cells 2017;35:898-908. © 2017 The Authors Stem Cells published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

Perspectives on the Use of Stem Cells for Autism Treatment

PubMed Central

Bradstreet, James Jeffrey; Antonucci, Nicola

2013-01-01

Autism and autism spectrum disorders (ASDs) are complex neurodevelopmental disorders. ASDs are clinically defined by deficits in communication, social skills, and repetitive and/or restrictive interests and behaviours. With the prevalence rates for ASDs rapidly increasing, the need for effective therapies for autism is a priority for biomedical research. Currently available medications do not target the core symptoms, can have markedly adverse side-effects, and are mainly palliative for negative behaviours. The development of molecular and regenerative interventions is progressing rapidly, and medicine holds great expectations for stem cell therapies. Cells could be designed to target the observed molecular mechanisms of ASDs, that is, abnormal neurotransmitter regulation, activated microglia, mitochondrial dysfunction, blood-brain barrier disruptions, and chronic intestinal inflammation. Presently, the paracrine, secretome, and immunomodulatory effects of stem cells would appear to be the likely mechanisms of application for ASD therapeutics. This review will focus on the potential use of the various types of stem cells: embryonic, induced pluripotential, fetal, and adult stem cells as targets for ASD therapeutics. PMID:24222772

Large-scale time-lapse microscopy of Oct4 expression in human embryonic stem cell colonies.

PubMed

Bhadriraju, Kiran; Halter, Michael; Amelot, Julien; Bajcsy, Peter; Chalfoun, Joe; Vandecreme, Antoine; Mallon, Barbara S; Park, Kye-Yoon; Sista, Subhash; Elliott, John T; Plant, Anne L

2016-07-01

Identification and quantification of the characteristics of stem cell preparations is critical for understanding stem cell biology and for the development and manufacturing of stem cell based therapies. We have developed image analysis and visualization software that allows effective use of time-lapse microscopy to provide spatial and dynamic information from large numbers of human embryonic stem cell colonies. To achieve statistically relevant sampling, we examined >680 colonies from 3 different preparations of cells over 5days each, generating a total experimental dataset of 0.9 terabyte (TB). The 0.5 Giga-pixel images at each time point were represented by multi-resolution pyramids and visualized using the Deep Zoom Javascript library extended to support viewing Giga-pixel images over time and extracting data on individual colonies. We present a methodology that enables quantification of variations in nominally-identical preparations and between colonies, correlation of colony characteristics with Oct4 expression, and identification of rare events. Copyright © 2016. Published by Elsevier B.V.

Neural differentiation of novel multipotent progenitor cells from cryopreserved human umbilical cord blood

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

Lee, Myoung Woo; Moon, Young Joon; Yang, Mal Sook

2007-06-29

Umbilical cord blood (UCB) is a rich source of hematopoietic stem cells, with practical and ethical advantages. To date, the presence of other stem cells in UCB remains to be established. We investigated whether other stem cells are present in cryopreserved UCB. Seeded mononuclear cells formed adherent colonized cells in optimized culture conditions. Over a 4- to 6-week culture period, colonized cells gradually developed into adherent mono-layer cells, which exhibited homogeneous fibroblast-like morphology and immunophenotypes, and were highly proliferative. Isolated cells were designated 'multipotent progenitor cells (MPCs)'. Under appropriate conditions for 2 weeks, MPCs differentiated into neural tissue-specific cell types,more » including neuron, astrocyte, and oligodendrocyte. Differentiated cells presented their respective markers, specifically, NF-L and NSE for neurons, GFAP for astrocytes, and myelin/oligodendrocyte for oligodendrocytes. In this study, we successfully isolated MPCs from cryopreserved UCB, which differentiated into the neural tissue-specific cell types. These findings suggest that cryopreserved human UCB is a useful alternative source of neural progenitor cells, such as MPCs, for experimental and therapeutic applications.« less

Single Stem Cell Imaging and Analysis Reveals Telomere Length Differences in Diseased Human and Mouse Skeletal Muscles.

PubMed

Tichy, Elisia D; Sidibe, David K; Tierney, Matthew T; Stec, Michael J; Sharifi-Sanjani, Maryam; Hosalkar, Harish; Mubarak, Scott; Johnson, F Brad; Sacco, Alessandra; Mourkioti, Foteini

2017-10-10

Muscle stem cells (MuSCs) contribute to muscle regeneration following injury. In many muscle disorders, the repeated cycles of damage and repair lead to stem cell dysfunction. While telomere attrition may contribute to aberrant stem cell functions, methods to accurately measure telomere length in stem cells from skeletal muscles have not been demonstrated. Here, we have optimized and validated such a method, named MuQ-FISH, for analyzing telomere length in MuSCs from either mice or humans. Our analysis showed no differences in telomere length between young and aged MuSCs from uninjured wild-type mice, but MuSCs isolated from young dystrophic mice exhibited significantly shortened telomeres. In corroboration, we demonstrated that telomere attrition is present in human dystrophic MuSCs, which underscores its importance in diseased regenerative failure. The robust technique described herein provides analysis at a single-cell resolution and may be utilized for other cell types, especially rare populations of cells. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Hydrogel microfluidics for the patterning of pluripotent stem cells

NASA Astrophysics Data System (ADS)

Cosson, S.; Lutolf, M. P.

2014-03-01

Biomolecular signaling is of utmost importance in governing many biological processes such as the patterning of the developing embryo where biomolecules regulate key cell-fate decisions. In vivo, these factors are presented in a spatiotemporally tightly controlled fashion. Although state-of-the-art microfluidic technologies allow precise biomolecule delivery in time and space, long-term (stem) cell culture at the micro-scale is often far from ideal due to medium evaporation, limited space for cell growth or shear stress. To overcome these challenges, we here introduce a concept based on hydrogel microfluidics for decoupling conventional, macro-scale cell culture from precise biomolecule delivery through a gel layer. We demonstrate the spatiotemporally controlled neuronal commitment of mouse embryonic stem cells via delivery of retinoic acid gradients. This technique should be useful for testing the effect of dose and timing of biomolecules, singly or in combination, on stem cell fate.

Differences between Parkinson's and Huntington's diseases and their role for prioritization of stem cell-based treatments.

PubMed

Hug, K; Hermerén, G

2013-06-01

The problems of allocation of scarce resources and priority setting in health care have so far not been much studied in the context of stem cell-based therapeutic applications. If and when competitive cost effective stem cell-based therapies are available, the problem of priority setting - to whom should stem cellbased therapies be offered and on what grounds - is discussed in this article using the examples of Parkinson's Disease (PD) and Huntington's Disease (HD). The aim of this paper is to examine the presently known differences between PD and HD and analyze the role of these differences for setting priorities of stem cell-based therapeutic applications to treat these diseases. To achieve this aim, we (1) present the theoretical framework used in the analysis; (2) compare PD and HD in terms of health related and non-health related consequences of these diseases for patients, their relatives and third parties; (3) analyze the ethical relevance of observed differences for priority setting given different values and variables; (4) compare PD and HD in terms of social justice related consequences of stem cell-based therapies; and (5) analyze the ethical relevance of these differences for priority setting given different values and variables. We argue that the steps of analysis applied in this paper could be helpful when setting priorities among treatments of other diseases with similar differences as those between PD and HD.

Advances of Stem Cell Therapeutics in Cutaneous Wound Healing and Regeneration

PubMed Central

Kanji, Suman

2017-01-01

Cutaneous wound healing is a complex multiple phase process, which overlaps each other, where several growth factors, cytokines, chemokines, and various cells interact in a well-orchestrated manner. However, an imbalance in any of these phases and factors may lead to disruption in harmony of normal wound healing process, resulting in transformation towards chronic nonhealing wounds and abnormal scar formation. Although various therapeutic interventions are available to treat chronic wounds, current wound-care has met with limited success. Progenitor stem cells possess potential therapeutic ability to overcome limitations of the present treatments as it offers accelerated wound repair with tissue regeneration. A substantial number of stem cell therapies for cutaneous wounds are currently under development as a result of encouraging preliminary findings in both preclinical and clinical studies. However, the mechanisms by which these stem cells contribute to the healing process have yet to be elucidated. In this review, we emphasize on the major treatment modalities currently available for the treatment of the wound, role of various interstitial stem cells and exogenous adult stem cells in cutaneous wound healing, and possible mechanisms involved in the healing process. PMID:29213192

Concise review: stem cell-derived erythrocytes as upcoming players in blood transfusion.

PubMed

Zeuner, Ann; Martelli, Fabrizio; Vaglio, Stefania; Federici, Giulia; Whitsett, Carolyn; Migliaccio, Anna Rita

2012-08-01

Blood transfusions have become indispensable to treat the anemia associated with a variety of medical conditions ranging from genetic disorders and cancer to extensive surgical procedures. In developed countries, the blood supply is generally adequate. However, the projected decline in blood donor availability due to population ageing and the difficulty in finding rare blood types for alloimmunized patients indicate a need for alternative red blood cell (RBC) transfusion products. Increasing knowledge of processes that govern erythropoiesis has been translated into efficient procedures to produce RBC ex vivo using primary hematopoietic stem cells, embryonic stem cells, or induced pluripotent stem cells. Although in vitro-generated RBCs have recently entered clinical evaluation, several issues related to ex vivo RBC production are still under intense scrutiny: among those are the identification of stem cell sources more suitable for ex vivo RBC generation, the translation of RBC culture methods into clinical grade production processes, and the development of protocols to achieve maximal RBC quality, quantity, and maturation. Data on size, hemoglobin, and blood group antigen expression and phosphoproteomic profiling obtained on erythroid cells expanded ex vivo from a limited number of donors are presented as examples of the type of measurements that should be performed as part of the quality control to assess the suitability of these cells for transfusion. New technologies for ex vivo erythroid cell generation will hopefully provide alternative transfusion products to meet present and future clinical requirements. Copyright © 2012 AlphaMed Press.

Extracellular Vesicles in Physiology, Pathology, and Therapy of the Immune and Central Nervous System, with Focus on Extracellular Vesicles Derived from Mesenchymal Stem Cells as Therapeutic Tools

PubMed Central

Koniusz, Sylwia; Andrzejewska, Anna; Muraca, Maurizio; Srivastava, Amit K.; Janowski, Miroslaw; Lukomska, Barbara

2016-01-01

Extracellular vesicles (EVs) are membrane-surrounded structures released by most cell types. They are characterized by a specific set of proteins, lipids and nucleic acids. EVs have been recognized as potent vehicles of intercellular communication to transmit biological signals between cells. In addition, pathophysiological roles of EVs in conditions like cancer, infectious diseases and neurodegenerative disorders are well established. In recent years focus has been shifted on therapeutic use of stem cell derived-EVs. Use of stem cell derived-EVs present distinct advantage over the whole stem cells as EVs do not replicate and after intravenous administration, they are less likely to trap inside the lungs. From the therapeutic perspective, the most promising cellular sources of EVs are mesenchymal stem cells (MSCs), which are easy to obtain and maintain. Therapeutic activity of MSCs has been shown in numerous animal models and the beneficial paracrine effect of MSCs may be mediated by EVs. The various components of MSC derived-EVs such as proteins, lipids, and RNA might play a specific therapeutic role. In this review, we characterize the role of EVs in immune and central nervous system (CNS); present evidences for defective signaling of these vesicles in neurodegeneration and therapeutic role of EVs in CNS. PMID:27199663

Adipose-derived Mesenchymal Stem Cells and Their Reparative Potential in Ischemic Heart Disease.

PubMed

Badimon, Lina; Oñate, Blanca; Vilahur, Gemma

2015-07-01

Adipose tissue has long been considered an energy storage and endocrine organ; however, in recent decades, this tissue has also been considered an abundant source of mesenchymal cells. Adipose-derived stem cells are easily obtained, show a strong capacity for ex vivo expansion and differentiation to other cell types, release a large variety of angiogenic factors, and have immunomodulatory properties. Thus, adipose tissue is currently the focus of considerable interest in the field of regenerative medicine. In the context of coronary heart disease, numerous experimental studies have supported the safety and efficacy of adipose-derived stem cells in the setting of myocardial infarction. These results have encouraged the clinical use of these stem cells, possibly prematurely. Indeed, the presence of cardiovascular risk factors, such as hypertension, coronary disease, diabetes mellitus, and obesity, alter and reduce the functionality of adipose-derived stem cells, putting in doubt the efficacy of their autologous implantation. In the present article, white adipose tissue is described, the stem cells found in this tissue are characterized, and the use of these cells is discussed according to the preclinical and clinical trials performed so far. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Global regulatory developments for clinical stem cell research: diversification and challenges to collaborations.

PubMed

Rosemann, Achim; Bortz, Gabriela; Vasen, Federico; Sleeboom-Faulkner, Margaret

2016-10-01

In this article, we explore regulatory developments in stem cell medicine in seven jurisdictions: Japan, China, India, Argentina, Brazil, the USA and the EU. We will show that the research methods, ethical standards and approval procedures for the market use of clinical stem cell interventions are undergoing an important process of global diversification. We will discuss the implications of this process for international harmonization and the conduct of multicountry clinical research collaborations. It will become clear that the increasing heterogeneity of research standards and regulations in the stem cell field presents a significant challenge to international clinical trial partnerships, especially with countries that diverge from the regulatory models that have been developed in the USA and the EU.

Patent prosecution strategies for stem cell related applications.

PubMed

Kumar, Rajeev; Yeh, Jenny J; Fernandez, Dennis; Hansen, Nels

2007-09-01

Stem cell research and the intellectual property derived from it, because of its potential to completely transform health care, demand an especially high level of consideration from business and patent prosecution perspectives. As with other revolutionary technologies, ordinary risks are amplified (e.g., litigation), and ordinarily irrelevant considerations may become important (e.g., heightened level of both domestic and foreign legislative risk). In the first part of this article, general strategies for patent prosecutors such as several prosecution considerations and methods for accelerating patent prosecution process are presented. In the second part, patent prosecution challenges of stem cell-related patents and possible solutions are discussed. In the final part, ethical and public policy issues particular to stem cell-related and other biotechnological inventions are summarized.

Quantitative stem cell biology: the threat and the glory.

PubMed

Pollard, Steven M

2016-11-15

Major technological innovations over the past decade have transformed our ability to extract quantitative data from biological systems at an unprecedented scale and resolution. These quantitative methods and associated large datasets should lead to an exciting new phase of discovery across many areas of biology. However, there is a clear threat: will we drown in these rivers of data? On 18th July 2016, stem cell biologists gathered in Cambridge for the 5th annual Cambridge Stem Cell Symposium to discuss 'Quantitative stem cell biology: from molecules to models'. This Meeting Review provides a summary of the data presented by each speaker, with a focus on quantitative techniques and the new biological insights that are emerging. © 2016. Published by The Company of Biologists Ltd.

National Hematopoietic Stem Cells Transplant Registry in Poland: Nationwide Internet Reporting System and Results.

PubMed

Łęczycka, A; Dudkiewicz, M; Czerwiński, J; Malanowski, P; Żalikowska-Hołoweńko, J; Danielewicz, R

2016-06-01

History of hematopoietic stem cell transplantations in Poland begins in early 1980s; the 1st bone marrow allotransplantation was performed in 1983 in the Central Clinical Hospital of the Military Medical Academy in Warsaw. Following years brought the 1st autologous stem cell transplantations. Ten years later, unrelated bone marrow transplantation was performed for the 1st time by the team of the Hematology and Blood and Marrow Transplantation Unit in Katowice. Since then, hematopoietic stem cell transplantation developed to be standard procedure and one of the most important therapies applied in leukemia treatment. The number of allotransplantations in Poland has grown significantly in the past 2 decades, which generated new needs and problems. In 2005, based on a new Transplant Law, a National Transplants Registry was created. Its main role is to collect data (registration of procedures and follow-up data) related to every transplantation case for stem cells and tissues as well as for organs. We present statistics concerning stem cell transplantations performed in Poland, as collected in the National Transplants Registry in the years 2006-2014. There are 18 centers transplanting hematopoietic stem cells in Poland. The total number of hematopoietic stem cell transplantations performed in 2006-2014 was 3,537, with allotransplantations from relatives accounted for 1,491 and from unrelated donors for 2,046. The main indication for allotransplantation in past years was acute leukemia. Copyright © 2016 Elsevier Inc. All rights reserved.

Real‐time monitoring of specific oxygen uptake rates of embryonic stem cells in a microfluidic cell culture device

PubMed Central

Super, Alexandre; Jaccard, Nicolas; Cardoso Marques, Marco Paulo; Macown, Rhys Jarred; Griffin, Lewis Donald; Veraitch, Farlan Singh

2016-01-01

Abstract Oxygen plays a key role in stem cell biology as a signaling molecule and as an indicator of cell energy metabolism. Quantification of cellular oxygen kinetics, i.e. the determination of specific oxygen uptake rates (sOURs), is routinely used to understand metabolic shifts. However current methods to determine sOUR in adherent cell cultures rely on cell sampling, which impacts on cellular phenotype. We present real‐time monitoring of cell growth from phase contrast microscopy images, and of respiration using optical sensors for dissolved oxygen. Time‐course data for bulk and peri‐cellular oxygen concentrations obtained for Chinese hamster ovary (CHO) and mouse embryonic stem cell (mESCs) cultures successfully demonstrated this non‐invasive and label‐free approach. Additionally, we confirmed non‐invasive detection of cellular responses to rapidly changing culture conditions by exposing the cells to mitochondrial inhibiting and uncoupling agents. For the CHO and mESCs, sOUR values between 8 and 60 amol cell−1 s−1, and 5 and 35 amol cell−1 s−1 were obtained, respectively. These values compare favorably with literature data. The capability to monitor oxygen tensions, cell growth, and sOUR, of adherent stem cell cultures, non‐invasively and in real time, will be of significant benefit for future studies in stem cell biology and stem cell‐based therapies. PMID:27214658

Isolation of Small SSEA-4-Positive Putative Stem Cells from the Ovarian Surface Epithelium of Adult Human Ovaries by Two Different Methods

PubMed Central

Virant-Klun, Irma; Skutella, Thomas; Hren, Matjaz; Gruden, Kristina; Cvjeticanin, Branko; Vogler, Andrej; Sinkovec, Jasna

2013-01-01

The adult ovarian surface epithelium has already been proposed as a source of stem cells and germinal cells in the literature, therefore it has been termed the “germinal epithelium”. At present more studies have confirmed the presence of stem cells expressing markers of pluripotency in adult mammalian ovaries, including humans. The aim of this study was to isolate a population of stem cells, based on the expression of pluripotency-related stage-specific embryonic antigen-4 (SSEA-4) from adult human ovarian surface epithelium by two different methods: magnetic-activated cell sorting and fluorescence-activated cell sorting. Both methods made it possible to isolate a similar, relatively homogenous population of small, SSEA-4-positive cells with diameters of up to 4 μm from the suspension of cells retrieved by brushing of the ovarian cortex biopsies in reproductive-age and postmenopausal women and in women with premature ovarian failure. The immunocytochemistry and genetic analyses revealed that these small cells—putative stem cells—expressed some primordial germ cell and pluripotency-related markers and might be related to the in vitro development of oocyte-like cells expressing some oocyte-specific transcription factors in the presence of donated follicular fluid with substances important for oocyte growth and development. The stemness of these cells needs to be further researched. PMID:23509763

Guiding the osteogenic fate of mouse and human mesenchymal stem cells through feedback system control.

PubMed

Honda, Yoshitomo; Ding, Xianting; Mussano, Federico; Wiberg, Akira; Ho, Chih-Ming; Nishimura, Ichiro

2013-12-05

Stem cell-based disease modeling presents unique opportunities for mechanistic elucidation and therapeutic targeting. The stable induction of fate-specific differentiation is an essential prerequisite for stem cell-based strategy. Bone morphogenetic protein 2 (BMP-2) initiates receptor-regulated Smad phosphorylation, leading to the osteogenic differentiation of mesenchymal stromal/stem cells (MSC) in vitro; however, it requires supra-physiological concentrations, presenting a bottleneck problem for large-scale drug screening. Here, we report the use of a double-objective feedback system control (FSC) with a differential evolution (DE) algorithm to identify osteogenic cocktails of extrinsic factors. Cocktails containing significantly reduced doses of BMP-2 in combination with physiologically relevant doses of dexamethasone, ascorbic acid, beta-glycerophosphate, heparin, retinoic acid and vitamin D achieved accelerated in vitro mineralization of mouse and human MSC. These results provide insight into constructive approaches of FSC to determine the applicable functional and physiological environment for MSC in disease modeling, drug screening and tissue engineering.

Autologous bone marrow stem cell transplantation for the treatment of postoperative hand infection with a skin defect in diabetes mellitus: A case report.

PubMed

Liu, Yihong; Liu, Yuchen; Wang, Pujie; Tian, Haoming; Ai, Jianzhong; Liu, Yangbo; Zhou, Yi; Liu, Zhongwen; Guo, Wenjun; Yang, Shenke

2014-06-01

Among stem cells, autologous mesenchymal stem cells (MSCs) are ideal for transplantation by virtue of limited rejection reactions and marked proliferative ability. This study presents a novel method by which MSCs were harvested from the bone marrow of a patient who presented with severe post-traumatic infection and a non-healing skin defect in the hand, secondary to uncontrolled diabetes mellitus (DM). An autologous MSC suspension was injected into the persistent skin defect after stabilizing the blood glucose level and appropriate infection control. During the course of a regular 18-month postoperative follow-up, the patient exhibited immediate recovery with no transplant-associated complications, as well as no evidence of tumorigenicity. Thus, transplantation of autologous MSCs may play a role in the clinical application of stem cells, particularly for treatment of skin defects following surgery in cases of DM and for those caused by various other traumas.

Guiding the osteogenic fate of mouse and human mesenchymal stem cells through feedback system control

PubMed Central

Honda, Yoshitomo; Ding, Xianting; Mussano, Federico; Wiberg, Akira; Ho, Chih-ming; Nishimura, Ichiro

2013-01-01

Stem cell-based disease modeling presents unique opportunities for mechanistic elucidation and therapeutic targeting. The stable induction of fate-specific differentiation is an essential prerequisite for stem cell-based strategy. Bone morphogenetic protein 2 (BMP-2) initiates receptor-regulated Smad phosphorylation, leading to the osteogenic differentiation of mesenchymal stromal/stem cells (MSC) in vitro; however, it requires supra-physiological concentrations, presenting a bottleneck problem for large-scale drug screening. Here, we report the use of a double-objective feedback system control (FSC) with a differential evolution (DE) algorithm to identify osteogenic cocktails of extrinsic factors. Cocktails containing significantly reduced doses of BMP-2 in combination with physiologically relevant doses of dexamethasone, ascorbic acid, beta-glycerophosphate, heparin, retinoic acid and vitamin D achieved accelerated in vitro mineralization of mouse and human MSC. These results provide insight into constructive approaches of FSC to determine the applicable functional and physiological environment for MSC in disease modeling, drug screening and tissue engineering. PMID:24305548

Pluripotency of Stem Cells from Human Exfoliated Deciduous Teeth for Tissue Engineering

PubMed Central

Rosa, Vinicius; Dubey, Nileshkumar; Islam, Intekhab; Min, Kyung-San; Nör, Jacques E.

2016-01-01

Stem cells from human exfoliated deciduous teeth (SHED) are highly proliferative pluripotent cells that can be retrieved from primary teeth. Although SHED are isolated from the dental pulp, their differentiation potential is not limited to odontoblasts only. In fact, SHED can differentiate into several cell types including neurons, osteoblasts, adipocytes, and endothelial cells. The high plasticity makes SHED an interesting stem cell model for research in several biomedical areas. This review will discuss key findings about the characterization and differentiation of SHED into odontoblasts, neurons, and hormone secreting cells (e.g., hepatocytes and islet-like cell aggregates). The outcomes of the studies presented here support the multipotency of SHED and their potential to be used for tissue engineering-based therapies. PMID:27313627

Extracellular Matrix from Periodontal Ligament Cells Could Induce the Differentiation of Induced Pluripotent Stem Cells to Periodontal Ligament Stem Cell-Like Cells.

PubMed

Hamano, Sayuri; Tomokiyo, Atsushi; Hasegawa, Daigaku; Yoshida, Shinichiro; Sugii, Hideki; Mitarai, Hiromi; Fujino, Shoko; Wada, Naohisa; Maeda, Hidefumi

2018-01-15

The periodontal ligament (PDL) plays an important role in anchoring teeth in the bone socket. Damage to the PDL, such as after severe inflammation, can be treated with a therapeutic strategy that uses stem cells derived from PDL tissue (PDLSCs), a strategy that has received intense scrutiny over the past decade. However, there is an insufficient number of PDLSCs within the PDL for treating such damage. Therefore, we sought to induce the differentiation of induced pluripotent stem (iPS) cells into PDLSCs as an initial step toward PDL therapy. To this end, we first induced iPS cells into neural crest (NC)-like cells. We then captured the p75 neurotrophic receptor-positive cells (iPS-NC cells) and cultured them on an extracellular matrix (ECM) produced by human PDL cells (iPS-NC-PDL cells). These iPS-NC-PDL cells showed reduced expression of embryonic stem cell and NC cell markers as compared with iPS and iPS-NC cells, and enrichment of mesenchymal stem cell markers. The cells also had a higher proliferative capacity, multipotency, and elevated expression of PDL-related markers than iPS-NC cells cultured on fibronectin and laminin (iPS-NC-FL cells) or ECM produced by human skin fibroblast cells (iPS-NC-SF cells). Overall, we present a culture method to produce high number of PDLSC-like cells from iPS cells as a first step toward a strategy for PDL regeneration.

An RNA-binding protein, Qki5, regulates embryonic neural stem cells through pre-mRNA processing in cell adhesion signaling.

PubMed

Hayakawa-Yano, Yoshika; Suyama, Satoshi; Nogami, Masahiro; Yugami, Masato; Koya, Ikuko; Furukawa, Takako; Zhou, Li; Abe, Manabu; Sakimura, Kenji; Takebayashi, Hirohide; Nakanishi, Atsushi; Okano, Hideyuki; Yano, Masato

2017-09-15

Cell type-specific transcriptomes are enabled by the action of multiple regulators, which are frequently expressed within restricted tissue regions. In the present study, we identify one such regulator, Quaking 5 (Qki5), as an RNA-binding protein (RNABP) that is expressed in early embryonic neural stem cells and subsequently down-regulated during neurogenesis. mRNA sequencing analysis in neural stem cell culture indicates that Qki proteins play supporting roles in the neural stem cell transcriptome and various forms of mRNA processing that may result from regionally restricted expression and subcellular localization. Also, our in utero electroporation gain-of-function study suggests that the nuclear-type Qki isoform Qki5 supports the neural stem cell state. We next performed in vivo transcriptome-wide protein-RNA interaction mapping to search for direct targets of Qki5 and elucidate how Qki5 regulates neural stem cell function. Combined with our transcriptome analysis, this mapping analysis yielded a bona fide map of Qki5-RNA interaction at single-nucleotide resolution, the identification of 892 Qki5 direct target genes, and an accurate Qki5-dependent alternative splicing rule in the developing brain. Last, our target gene list provides the first compelling evidence that Qki5 is associated with specific biological events; namely, cell-cell adhesion. This prediction was confirmed by histological analysis of mice in which Qki proteins were genetically ablated, which revealed disruption of the apical surface of the lateral wall in the developing brain. These data collectively indicate that Qki5 regulates communication between neural stem cells by mediating numerous RNA processing events and suggest new links between splicing regulation and neural stem cell states. © 2017 Hayakawa-Yano et al.; Published by Cold Spring Harbor Laboratory Press.

Seamless Combination of Fluorescence-Activated Cell Sorting and Hanging-Drop Networks for Individual Handling and Culturing of Stem Cells and Microtissue Spheroids.

PubMed

Birchler, Axel; Berger, Mischa; Jäggin, Verena; Lopes, Telma; Etzrodt, Martin; Misun, Patrick Mark; Pena-Francesch, Maria; Schroeder, Timm; Hierlemann, Andreas; Frey, Olivier

2016-01-19

Open microfluidic cell culturing devices offer new possibilities to simplify loading, culturing, and harvesting of individual cells or microtissues due to the fact that liquids and cells/microtissues are directly accessible. We present a complete workflow for microfluidic handling and culturing of individual cells and microtissue spheroids, which is based on the hanging-drop network concept: The open microfluidic devices are seamlessly combined with fluorescence-activated cell sorting (FACS), so that individual cells, including stem cells, can be directly sorted into specified culturing compartments in a fully automated way and at high accuracy. Moreover, already assembled microtissue spheroids can be loaded into the microfluidic structures by using a conventional pipet. Cell and microtissue culturing is then performed in hanging drops under controlled perfusion. On-chip drop size control measures were applied to stabilize the system. Cells and microtissue spheroids can be retrieved from the chip by using a parallelized transfer method. The presented methodology holds great promise for combinatorial screening of stem-cell and multicellular-spheroid cultures.

Exploiting science? A systematic analysis of complementary and alternative medicine clinic websites’ marketing of stem cell therapies

PubMed Central

Murdoch, Blake; Zarzeczny, Amy; Caulfield, Timothy

2018-01-01

Objective To identify the frequency and qualitative characteristics of stem cell-related marketing claims made on websites of clinics featuring common types of complementary and alternative medicine practitioners. The involvement of complementary and alternative medicine practitioners in the marketing of stem cell therapies and stem cell-related interventions is understudied. This research explores the extent to which they are involved and collaborate with medical professionals. This knowledge will help with identifying and evaluating potential policy responses to this growing market. Design Systematic website analysis. Setting Global. US and English-language bias due to methodology. Main outcome measures Representations made on clinic websites in relation to practitioner types, stem cell therapies and their targets, stem cell-related interventions. Statements about stem cell therapies relating to evidence of inefficacy, limited evidence of efficacy, general procedural risks, risks specific to the mode of therapy, regulatory status, experimental or unproven nature of therapy. Use of hype language (eg, language that exaggerates potential benefits). Results 243 websites offered stem cell therapies. Many websites advertised stem cell transplantation from multiple sources, such as adipose-derived (112), bone marrow-derived (100), blood-derived (28), umbilical cord-derived (26) and others. Plant stem cell-based treatments and products (20) were also advertised. Purposes for and targets of treatment included pain, physical injury, a wide range of diseases and illnesses, cosmetic concerns, non-cosmetic ageing, sexual enhancement and others. Medical doctors (130), chiropractors (53) and naturopaths (44) commonly work in the clinics we found to be offering stem cell therapies. Few clinic websites advertising stem cell therapies included important additional information, including statements about evidence of inefficacy (present on only 12.76% of websites), statements about limited evidence of efficacy (18.93%), statements of general risks (24.69%), statements of risks specific to the mode(s) of therapy (5.76%), statements as to the regulatory status of the therapies (30.86%) and statements that the therapy is experimental or unproven (33.33%). Hype language was noted (31.69%). Conclusions Stem cell therapies and related interventions are marketed for a wide breadth of conditions and are being offered by complementary and alternative practitioners, often in conjunction with medical doctors. Consumer protection and truth-in-advertising regulation could play important roles in addressing misleading marketing practices in this area. PMID:29490963

Generation of diverse neuronal subtypes in cloned populations of stem-like cells

PubMed Central

Varga, Balázs V; Hádinger, Nóra; Gócza, Elen; Dulberg, Vered; Demeter, Kornél; Madarász, Emília; Herberth, Balázs

2008-01-01

Background The central nervous tissue contains diverse subtypes of neurons with characteristic morphological and physiological features and different neurotransmitter phenotypes. The generation of neurons with defined neurotransmitter phenotypes seems to be governed by factors differently expressed along the anterior-posterior and dorsal-ventral body axes. The mechanisms of the cell-type determination, however, are poorly understood. Selected neuronal phenotypes had been generated from embryonic stem (ES) cells, but similar results were not obtained on more restricted neural stem cells, presumably due to the lack of homogeneous neural stem cell populations as a starting material. Results In the presented work, the establishment of different neurotransmitter phenotypes was investigated in the course of in vitro induced neural differentiation of a one-cell derived neuroectodermal cell line, in conjunction with the activation of various region-specific genes. For comparison, similar studies were carried out on the R1 embryonic stem (ES) and P19 multipotent embryonic carcinoma (EC) cells. In response to a short treatment with all-trans retinoic acid, all cell lines gave rise to neurons and astrocytes. Non-induced neural stem cells and self-renewing cells persisting in differentiated cultures, expressed "stemness genes" along with early embryonic anterior-dorsal positional genes, but did not express the investigated CNS region-specific genes. In differentiating stem-like cell populations, on the other hand, different region-specific genes, those expressed in non-overlapping regions along the body axes were activated. The potential for diverse regional specifications was induced in parallel with the initiation of neural tissue-type differentiation. In accordance with the wide regional specification potential, neurons with different neurotransmitter phenotypes developed. Mechanisms inherent to one-cell derived neural stem cell populations were sufficient to establish glutamatergic and GABAergic neuronal phenotypes but failed to manifest cathecolaminergic neurons. Conclusion The data indicate that genes involved in positional determination are activated along with pro-neuronal genes in conditions excluding any outside influences. Interactions among progenies of one cell derived neural stem cells are sufficient for the activation of diverse region specific genes and initiate different routes of neuronal specification. PMID:18808670

Telocytes in meninges and choroid plexus.

PubMed

Popescu, B O; Gherghiceanu, M; Kostin, S; Ceafalan, L; Popescu, L M

2012-05-16

Telocytes (TCs) are a recently identified type of interstitial cells present in a wide variety of organs in humans and mammals (www.telocytes.com). They are characterized by a small cell body, but extremely long cell processes - telopodes (Tp), and a specific phenotype. TCs establish close contacts with blood capillaries, nerve fibers and stem cells. We report here identification of TCs by electron microscopy and immunofluorescence in rat meninges and choroid plexus/subventricular zone, in the vicinity of putative stem cells. The presence of TCs in brain areas involved in adult neurogenesis might indicate that they have a role in modulation of neural stem cell fate. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Stem Cell Therapies in Retinal Disorders.

PubMed

Garg, Aakriti; Yang, Jin; Lee, Winston; Tsang, Stephen H

2017-02-02

Stem cell therapy has long been considered a promising mode of treatment for retinal conditions. While human embryonic stem cells (ESCs) have provided the precedent for regenerative medicine, the development of induced pluripotent stem cells (iPSCs) revolutionized this field. iPSCs allow for the development of many types of retinal cells, including those of the retinal pigment epithelium, photoreceptors, and ganglion cells, and can model polygenic diseases such as age-related macular degeneration. Cellular programming and reprogramming technology is especially useful in retinal diseases, as it allows for the study of living cells that have genetic variants that are specific to patients' diseases. Since iPSCs are a self-renewing resource, scientists can experiment with an unlimited number of pluripotent cells to perfect the process of targeted differentiation, transplantation, and more, for personalized medicine. Challenges in the use of stem cells are present from the scientific, ethical, and political realms. These include transplant complications leading to anatomically incorrect placement, concern for tumorigenesis, and incomplete targeting of differentiation leading to contamination by different types of cells. Despite these limitations, human ESCs and iPSCs specific to individual patients can revolutionize the study of retinal disease and may be effective therapies for conditions currently considered incurable.

Substrate micropatterns produced by polymer demixing regulate focal adhesions, actin anisotropy, and lineage differentiation of stem cells.

PubMed

Vega, Sebastián L; Arvind, Varun; Mishra, Prakhar; Kohn, Joachim; Sanjeeva Murthy, N; Moghe, Prabhas V

2018-06-12

Stem cells are adherent cells whose multipotency and differentiation can be regulated by numerous microenvironmental signals including soluble growth factors and surface topography. This study describes a simple method for creating distinct micropatterns via microphase separation resulting from polymer demixing of poly(desaminotyrosyl-tyrosine carbonate) (PDTEC) and polystyrene (PS). Substrates with co-continuous (ribbons) or discontinuous (islands and pits) PDTEC regions were obtained by varying the ratio of PDTEC and sacrificial PS. Human mesenchymal stem cells (MSCs) cultured on co-continuous PDTEC substrates for 3 days in bipotential adipogenic/osteogenic (AD/OS) induction medium showed no change in cell morphology but exhibited increased anisotropic cytoskeletal organization and larger focal adhesions when compared to MSCs cultured on discontinuous micropatterns. After 14 days in bipotential AD/OS induction medium, MSCs cultured on co-continuous micropatterns exhibited increased expression of osteogenic markers, whereas MSCs on discontinuous PDTEC substrates showed a low expression of adipogenic and osteogenic differentiation markers. Substrates with graded micropatterns were able to reproduce the influence of local underlying topography on MSC differentiation, thus demonstrating their potential for high throughput analysis. This work presents polymer demixing as a simple, non-lithographic technique to produce a wide range of micropatterns on surfaces with complex geometries to influence cellular and tissue regenerative responses. Gaining a better understanding of how engineered microenvironments influence stem cell differentiation is integral to increasing the use of stem cells and materials in a wide range of tissue engineering applications. In this study, we show the range of topography obtained by polymer demixing is sufficient for investigating how surface topography affects stem cell morphology and differentiation. Our findings show that co-continuous topographies favor early (3-day) cytoskeletal anisotropy and focal adhesion maturation as well as long-term (14-day) expression of osteogenic differentiation markers. Taken together, this study presents a simple approach to pattern topographies that induce divergent responses in stem cell morphology and differentiation. Copyright © 2018. Published by Elsevier Ltd.

Large-scale production of embryonic red blood cells from human embryonic stem cells.

PubMed

Olivier, Emmanuel N; Qiu, Caihong; Velho, Michelle; Hirsch, Rhoda Elison; Bouhassira, Eric E

2006-12-01

To develop a method to produce in culture large number of erythroid cells from human embryonic stem cells. Human H1 embryonic stem cells were differentiated into hematopoietic cells by coculture with a human fetal liver cell line, and the resulting CD34-positive cells were expanded in vitro in liquid culture using a three-step method. The erythroid cells produced were then analyzed by light microscopy and flow cytometry. Globin expression was characterized by quantitative reverse-transcriptase polymerase chain reaction and by high-performance liquid chromatography. CD34-positive cells produced from human embryonic stem cells could be efficiently differentiated into erythroid cells in liquid culture leading to a more than 5000-fold increase in cell number. The erythroid cells produced are similar to primitive erythroid cells present in the yolk sac of early human embryos and did not enucleate. They are fully hemoglobinized and express a mixture of embryonic and fetal globins but no beta-globin. We have developed an experimental protocol to produce large numbers of primitive erythroid cells starting from undifferentiated human embryonic stem cells. As the earliest human erythroid cells, the nucleated primitive erythroblasts, are not very well characterized because experimental material at this stage of development is very difficult to obtain, this system should prove useful to answer a number of experimental questions regarding the biology of these cells. In addition, production of mature red blood cells from human embryonic stem cells is of great potential practical importance because it could eventually become an alternate source of cell for transfusion.

Structural Complexity of Non-acid Glycosphingolipids in Human Embryonic Stem Cells Grown under Feeder-free Conditions*

PubMed Central

Barone, Angela; Benktander, John; Ångström, Jonas; Aspegren, Anders; Björquist, Petter; Teneberg, Susann; Breimer, Michael. E.

2013-01-01

Due to their pluripotency and growth capability, there are great expectations for human embryonic stem cells, both as a resource for functional studies of early human development and as a renewable source of cells for use in regenerative medicine and transplantation. However, to bring human embryonic stem cells into clinical applications, their cell surface antigen expression and its chemical structural complexity have to be defined. In the present study, total non-acid glycosphingolipid fractions were isolated from two human embryonic stem cell lines (SA121 and SA181) originating from leftover in vitro fertilized human embryos, using large amounts of starting material (1 × 109 cells/cell line). The total non-acid glycosphingolipid fractions were characterized by antibody and lectin binding, mass spectrometry, and proton NMR. In addition to the globo-series and type 1 core chain glycosphingolipids previously described in human embryonic stem cells, a number of type 2 core chain glycosphingolipids (neo-lactotetraosylceramide, the H type 2 pentaosylceramide, the Lex pentaosylceramide, and the Ley hexaosylceramide) were identified as well as the blood group A type 1 hexaosylceramide. Finally, the mono-, di-, and triglycosylceramides were characterized as galactosylceramide, glucosylceramide, lactosylceramide, galabiaosylceramide, globotriaosylceramide, and lactotriaosylceramide. Thus, the glycan diversity of human embryonic stem cells, including cell surface immune determinants, is more complex than previously appreciated. PMID:23404501

Differentiation and Transplantation of Human Embryonic Stem Cell-Derived Hepatocytes

PubMed Central

Basma, Hesham; Soto-Gutiérrez, Alejandro; Yannam, Govardhana Rao; Liu, Liping; Ito, Ryotaro; Yamamoto, Toshiyuki; Ellis, Ewa; Carson, Steven D.; Sato, Shintaro; Chen, Yong; Muirhead, David; Navarro-Álvarez, Nalu; Wong, Ron; Roy-Chowdhury, Jayanta; Platt, Jeffrey L.; Mercer, David F.; Miller, John D.; Strom, Stephen C.; Kobayashi, Noaya; Fox, Ira J.

2009-01-01

Background & Aims The ability to obtain unlimited numbers of human hepatocytes would improve development of cell-based therapies for liver diseases, facilitate the study of liver biology and improve the early stages of drug discovery. Embryonic stem cells are pluripotent, can potentially differentiate into any cell type and could therefore be developed as a source of human hepatocytes. Methods To generate human hepatocytes, human embryonic stem cells were differentiated by sequential culture in fibroblast growth factor 2 and human Activin-A, hepatocyte growth factor, and dexamethasone. Functional hepatocytes were isolated by sorting for surface asialoglycoprotein receptor expression. Characterization was performed by real-time PCR, imunohistochemistry, immunoblot, functional assays and transplantation. Results Embryonic stem cell-derived hepatocytes expressed liver-specific genes but not genes representing other lineages, secreted functional human liver-specific proteins similar to those of primary human hepatocytes and demonstrated human hepatocyte cytochrome P450 metabolic activity. Serum from rodents given injections of embryonic stem cell-derived hepatocytes contained significant amounts of human albumin and alpha-1-antitrypsin. Colonies of cytokeratin-18 and human albumin-expressing cells were present in the livers of recipient animals. Conclusion Human embryonic stem cells can be differentiated into cells with many characteristics of primary human hepatocytes. Hepatocyte-like cells can be enriched and recovered based on asialoglycoprotein receptor expression and could potentially be used in drug discovery research and developed as therapeutics. PMID:19026649

Real-time monitoring of specific oxygen uptake rates of embryonic stem cells in a microfluidic cell culture device.

PubMed

Super, Alexandre; Jaccard, Nicolas; Cardoso Marques, Marco Paulo; Macown, Rhys Jarred; Griffin, Lewis Donald; Veraitch, Farlan Singh; Szita, Nicolas

2016-09-01

Oxygen plays a key role in stem cell biology as a signaling molecule and as an indicator of cell energy metabolism. Quantification of cellular oxygen kinetics, i.e. the determination of specific oxygen uptake rates (sOURs), is routinely used to understand metabolic shifts. However current methods to determine sOUR in adherent cell cultures rely on cell sampling, which impacts on cellular phenotype. We present real-time monitoring of cell growth from phase contrast microscopy images, and of respiration using optical sensors for dissolved oxygen. Time-course data for bulk and peri-cellular oxygen concentrations obtained for Chinese hamster ovary (CHO) and mouse embryonic stem cell (mESCs) cultures successfully demonstrated this non-invasive and label-free approach. Additionally, we confirmed non-invasive detection of cellular responses to rapidly changing culture conditions by exposing the cells to mitochondrial inhibiting and uncoupling agents. For the CHO and mESCs, sOUR values between 8 and 60 amol cell(-1) s(-1) , and 5 and 35 amol cell(-1) s(-1) were obtained, respectively. These values compare favorably with literature data. The capability to monitor oxygen tensions, cell growth, and sOUR, of adherent stem cell cultures, non-invasively and in real time, will be of significant benefit for future studies in stem cell biology and stem cell-based therapies. © 2016 The Authors. Biotechnology Journal published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cellular reprogramming in skin cancer.

PubMed

Song, Ihn Young; Balmain, Allan

2015-06-01

Early primitive stem cells have long been viewed as the cancer cells of origin (tumor initiating target cells) due to their intrinsic features of self-renewal and longevity. However, emerging evidence suggests a surprising capacity for normal committed cells to function as reserve stem cells upon reprogramming as a consequence of tissue damage resulting in inflammation and wound healing. This results in an alternative concept positing that tumors may originate from differentiated cells that can re-acquire stem cell properties due to genetic or epigenetic reprogramming. It is likely that both models are correct, and that a continuum of potential cells of origin exists, ranging from early primitive stem cells to committed progenitor or even terminally differentiated cells. A combination of the nature of the target cell and the specific types of gene mutations introduced determine tumor cell lineage, as well as potential for malignant conversion. Evidence from mouse skin models of carcinogenesis suggests that initiated cells at different stages within a stem cell hierarchy have varying degrees of requirement for reprogramming (e.g. inflammation stimuli), depending on their degree of differentiation. This article will present evidence in favor of these concepts that has been developed from studies of several mouse models of skin carcinogenesis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Recent developments of the in situ wet cell technology for transmission electron microscopies.

PubMed

Chen, Xin; Li, Chang; Cao, Hongling

2015-03-21

In situ wet cells for transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) allow studying structures and processes in a liquid environment with high temporal and spatial resolutions, and have been attracting increasing research interests in many fields. In this review, we highlight the structural and functional developments of the wet cells for TEM and STEM. One of the key features of the wet cells is the sealing technique used to isolate the liquid sample from the TEM/STEM vacuum environments, thus the existing in situ wet cells are grouped by different sealing methods. In this study, the advantages and shortcomings of each type of in situ wet cells are discussed, the functional developments of different wet cells are presented, and the future trends of the wet cell technology are addressed. It is suggested that in the future the in situ wet cell TEM/STEM technology will have an increasing impact on frontier nanoscale research.

Tumor-Initiating Label-Retaining Cancer Cells in Human Gastrointestinal Cancers Undergo Asymmetric Cell Division

PubMed Central

Xin, Hong-Wu; Hari, Danielle M.; Mullinax, John E.; Ambe, Chenwi M.; Koizumi, Tomotake; Ray, Satyajit; Anderson, Andrew J.; Wiegand, Gordon W.; Garfield, Susan H.; Thorgeirsson, Snorri S.; Avital, Itzhak

2012-01-01

Label-retaining cells (LRCs) have been proposed to represent adult tissue stem cells. LRCs are hypothesized to result from either slow cycling or asymmetric cell division (ACD). However, the stem cell nature and whether LRC undergo ACD remain controversial. Here, we demonstrate label-retaining cancer cells (LRCCs) in several gastrointestinal (GI) cancers including fresh surgical specimens. Using a novel method for isolation of live LRCC, we demonstrate that a subpopulation of LRCC is actively dividing and exhibits stem cells and pluripotency gene expression profiles. Using real-time confocal microscopic cinematography, we show live LRCC undergoing asymmetric nonrandom chromosomal cosegregation LRC division. Importantly, LRCCs have greater tumor-initiating capacity than non-LRCCs. Based on our data and that cancers develop in tissues that harbor normal-LRC, we propose that LRCC might represent a novel population of GI stem-like cancer cells. LRCC may provide novel mechanistic insights into the biology of cancer and regenerative medicine and present novel targets for cancer treatment. PMID:22331764

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.

The response of breast cancer cells to mesenchymal stem cells: a possible role of inflammation by breast implants.

PubMed

Orciani, Monia; Lazzarini, Raffaella; Scartozzi, Mario; Bolletta, Elisa; Mattioli-Belmonte, Monica; Scalise, Alessandro; Di Benedetto, Giovanni; Di Primio, Roberto

2013-12-01

Breast implants are widely used and at times might cause inflammation as a foreign body, followed by fibrous capsule formation around the implant. In cancer, the inflamed stroma is essential for preservation of the tumor. Mesenchymal stem cells can be recruited to sites of inflammation, and their role in cancer development is debated. The authors assessed the effects of inflammation caused by breast implants' effects on tumor. Mesenchymal stem cells were isolated from the fibrous capsules of women who underwent a second operation after 1 year (presenting inflammation) or after 20 years (not presenting inflammation) since initial surgery. After characterization, cells were co-cultured with MCF7, a breast cancer cell line. The expression of genes involved in oncogenesis, proliferation, and epithelial-to-mesenchymal transition was investigated, followed by Western blot analyses. After co-culture with mesenchymal stem cells from the inflamed capsule, MCF7 induced a dose- and time-dependent increase in proliferation. Polymerase chain reaction analyses revealed a dysregulation of genes involved in oncogenesis, proliferation, and epithelial-to-mesenchymal transition. The subsequent evaluation by Western blot did not confirm these results, showing only a modest decrease in the expression of E-cadherin after co-culture with mesenchymal stem cells (both derived from inflamed or control capsules). These data indicate that inflammation caused by breast implants partially affects proliferation of MCF7 but does not influence key mechanisms of tumor development.

Analysis of type II diabetes mellitus adipose-derived stem cells for tissue engineering applications

PubMed Central

Minteer, Danielle Marie; Young, Matthew T; Lin, Yen-Chih; Over, Patrick J; Rubin, J Peter; Gerlach, Jorg C

2015-01-01

To address the functionality of diabetic adipose-derived stem cells in tissue engineering applications, adipose-derived stem cells isolated from patients with and without type II diabetes mellitus were cultured in bioreactor culture systems. The adipose-derived stem cells were differentiated into adipocytes and maintained as functional adipocytes. The bioreactor system utilizes a hollow fiber–based technology for three-dimensional perfusion of tissues in vitro, creating a model in which long-term culture of adipocytes is feasible, and providing a potential tool useful for drug discovery. Daily metabolic activity of the adipose-derived stem cells was analyzed within the medium recirculating throughout the bioreactor system. At experiment termination, tissues were extracted from bioreactors for immunohistological analyses in addition to gene and protein expression. Type II diabetic adipose-derived stem cells did not exhibit significantly different glucose consumption compared to adipose-derived stem cells from patients without type II diabetes (p > 0.05, N = 3). Expression of mature adipocyte genes was not significantly different between diabetic/non-diabetic groups (p > 0.05, N = 3). Protein expression of adipose tissue grown within all bioreactors was verified by Western blotting.The results from this small-scale study reveal adipose-derived stem cells from patients with type II diabetes when removed from diabetic environments behave metabolically similar to the same cells of non-diabetic patients when cultured in a three-dimensional perfusion bioreactor, suggesting that glucose transport across the adipocyte cell membrane, the hindrance of which being characteristic of type II diabetes, is dependent on environment. The presented observation describes a tissue-engineered tool for long-term cell culture and, following future adjustments to the culture environment and increased sample sizes, potentially for anti-diabetic drug testing. PMID:26090087

Awareness of Stem cells & Health Implications of SHED found in Pediatric Dentition among Indian Population

PubMed Central

Goomer, Pallvi; Sidhu, Arshpreet Kaur; Tuli, Preety; Kansal, Shinam; Bansal, Kanishka; Thakre, Gauri R

2014-01-01

Background: Primary teeth may be an ideal source of postnatal stem cells to regenerate tooth structures and bone, and possibly to treat neural tissue injury or degenerative diseases. SHED (stem cells from human exfoliated deciduous teeth) were identified to be a population of highly proliferative, clonogenic cells capable of differentiating into a variety of cell types including neural cells, adipocytes, and odontoblasts. The present study was carried out to assess the knowledge, awareness & attitude of parents visiting various dental clinics in tricity area of india regarding stem cells from primary teeth and their potential health benefits. Materials & Methods: A total of 250 parents of pediatric patients seeking dental treatment at various dental clinics in tricity area were included in the study. Parents were personally interviewed with a questionnaire and their responses were immediately computed. Results: Among 250 parents only 95(62%) had knowledge regarding stem cells. While only 47(18.8) were informed regarding stem cells from baby teeth & their benefits. Maximum subjects were informed through internet 21(44.6%) followed by information through friends(23.4%) and dentist(21.2%). Very few were informed through magazines, newspaper and only one (2.1%) person was informed by television. Conclusion: It is important to create more awareness among the populace of our country about the potential health benefits of stem cells from primary teeth. Dentist should educate parents, caregivers and teachers regarding SHED & its benefits, ensuring good health for every Indian child and hence health of future citizens. How to cite the article: Goomer P, Sidhu AK, Tuli P, Kansal S, Bansal K, Thakre GR. Awareness of Stem cells & Health Implications of SHED found in Pediatric Dentition among Indian Population. J Int Oral Health 2014;6(1):44-7. PMID:24653602

Sox2, Tlx, Gli3, and Her9 converge on Rx2 to define retinal stem cells in vivo

PubMed Central

Reinhardt, Robert; Centanin, Lázaro; Tavhelidse, Tinatini; Inoue, Daigo; Wittbrodt, Beate; Concordet, Jean-Paul; Martinez-Morales, Juan Ramón; Wittbrodt, Joachim

2015-01-01

Transcriptional networks defining stemness in adult neural stem cells (NSCs) are largely unknown. We used the proximal cis-regulatory element (pCRE) of the retina-specific homeobox gene 2 (rx2) to address such a network. Lineage analysis in the fish retina identified rx2 as marker for multipotent NSCs. rx2-positive cells located in the peripheral ciliary marginal zone behave as stem cells for the neuroretina, or the retinal pigmented epithelium. We identified upstream regulators of rx2 interrogating the rx2 pCRE in a trans-regulation screen and focused on four TFs (Sox2, Tlx, Gli3, and Her9) activating or repressing rx2 expression. We demonstrated direct interaction of the rx2 pCRE with the four factors in vitro and in vivo. By conditional mosaic gain- and loss-of-function analyses, we validated the activity of those factors on regulating rx2 transcription and consequently modulating neuroretinal and RPE stem cell features. This becomes obvious by the rx2-mutant phenotypes that together with the data presented above identify rx2 as a transcriptional hub balancing stemness of neuroretinal and RPE stem cells in the adult fish retina. PMID:25908840

Sox2, Tlx, Gli3, and Her9 converge on Rx2 to define retinal stem cells in vivo.

PubMed

Reinhardt, Robert; Centanin, Lázaro; Tavhelidse, Tinatini; Inoue, Daigo; Wittbrodt, Beate; Concordet, Jean-Paul; Martinez-Morales, Juan Ramón; Wittbrodt, Joachim

2015-06-03

Transcriptional networks defining stemness in adult neural stem cells (NSCs) are largely unknown. We used the proximal cis-regulatory element (pCRE) of the retina-specific homeobox gene 2 (rx2) to address such a network. Lineage analysis in the fish retina identified rx2 as marker for multipotent NSCs. rx2-positive cells located in the peripheral ciliary marginal zone behave as stem cells for the neuroretina, or the retinal pigmented epithelium. We identified upstream regulators of rx2 interrogating the rx2 pCRE in a trans-regulation screen and focused on four TFs (Sox2, Tlx, Gli3, and Her9) activating or repressing rx2 expression. We demonstrated direct interaction of the rx2 pCRE with the four factors in vitro and in vivo. By conditional mosaic gain- and loss-of-function analyses, we validated the activity of those factors on regulating rx2 transcription and consequently modulating neuroretinal and RPE stem cell features. This becomes obvious by the rx2-mutant phenotypes that together with the data presented above identify rx2 as a transcriptional hub balancing stemness of neuroretinal and RPE stem cells in the adult fish retina. © 2015 The Authors. Published under the terms of the CC BY NC ND 4.0 license.

Zinc suppresses stem cell properties of lung cancer cells through protein kinase C-mediated β-catenin degradation.

PubMed

Ninsontia, Chuanpit; Phiboonchaiyanan, Preeyaporn Plaimee; Kiratipaiboon, Chayanin; Chanvorachote, Pithi

2017-04-01

Highly tumorigenic cancer stem cells (CSCs) residing in most cancers are responsible for cancer progression and treatment failure. Zinc is an element regulator of several cell functions; however, its role in regulation of stem cell program in lung cancer has not been demonstrated. The present study reveals for the first time that zinc can suppress stem cell properties of lung cancer cells. Such findings were proved in different lung cancer cell lines (H460, H23, and H292) and it was found that CSC markers (CD133 and ALDH1A1), stem cell-associated transcription factors (Oct4, Nanog, and Sox-2), and the ability to form tumor spheroid were dramatically suppressed by zinc treatments. Zinc was found to activate protein kinase C-α (PKCα) that further phosphorylated and mediated β-catenin degradation through the ubiquitin-proteasomal pathway. Zinc was found to increase the β-catenin-ubiquitin complex, which can be inhibited by a specific PKC inhibitor, bisindolylmaleimide I. Using specific reactive oxygen species detection and antioxidants, we have demonstrated that superoxide anions generated by zinc are a key upstream mechanism for PKCα activation leading to the subsequent suppression of stem cell features of lung cancer. Zinc increased cellular superoxide anions and the addition of superoxide anion scavenger prevented the activation of PKCα and β-catenin degradation. These findings indicate a novel role for zinc regulation in the PKCα/β-catenin pathway and explain an important mechanism for controlling of stem cell program in lung cancer cells. Copyright © 2017 the American Physiological Society.

Highly osteogenic PDL stem cell clones specifically express elevated levels of ICAM1, ITGB1 and TERT.

PubMed

Sununliganon, Laddawun; Singhatanadgit, Weerachai

2012-01-01

Cells derived from the periodontal ligament (PDL) have previously been reported to have stem cell-like characteristics (PDL stem cells; PDLSCs) and play an important part in bone engineering, including that of alveolar bone. However, these populations have been heterogeneous, and thus far no specific marker has yet been established from adult human stem cells derived from PDL tissue. We have previously isolated highly purified single cell-derived PDLSC clones and delineated their phenotypic and functional characteristics. In this report, we further obtained three homogeneous and distinct PDLSC clones demonstrating low, moderate and high mineralized matrix forming ability-namely PC12, PC4 and PC3, respectively, and the expression of mesenchymal stem cell pathway-specific genes in these clones was investigated. PCR array revealed that the expression of intercellular adhesion molecule 1 (ICAM1), integrin beta 1 (ITGB1) and telomerase reverse transcriptase (TERT) was associated with highly osteogenic PDLSC clones, as determined by the expression of key osteoblastic markers and their ability to form alizarin red S positive mineralized matrix in vitro. The present results suggest that these three mesenchymal stem cell-associated markers could potentially be used to isolate PDLSCs with high osteogenic capability for engineering new bone.

Ultrastructural demonstration of Cx43 gap junctions in induced pluripotent stem cells from human cord blood.

PubMed

Beckmann, Anja; Schubert, Madline; Hainz, Nadine; Haase, Alexandra; Martin, Ulrich; Tschernig, Thomas; Meier, Carola

2016-11-01

Gap junction proteins are essential for direct intercellular communication but also influence cellular differentiation and migration. The expression of various connexin gap junction proteins has been demonstrated in embryonic stem cells, with Cx43 being the most intensely studied. As Cx43 is the most prominent gap junction protein in the heart, cardiomyocyte-differentiated stem cells have been studied intensely. To date, however, little is known about the expression and the subcellular distribution of Cx43 in undifferentiated stem cells or about the structural arrangement of channels. We, therefore, here investigate expression of Cx43 in undifferentiated human cord-blood-derived induced pluripotent stem cells (hCBiPS2). For this purpose, we carried out quantitative real-time PCR and immunohistochemistry. For analysis of Cx43 ultrastructure and protein assembly, we performed freeze-fracture replica immunogold labeling (FRIL). Cx43 expression was detected at mRNA and protein level in hCBIPS2 cells. For the first time, ultrastructural data are presented on gap junction morphology in induced pluripotent stem (iPS) cells from cord blood: Our FRIL and electron microscopical analysis revealed the occurrence of gap junction plaques in undifferentiated iPS cells. In addition, these gap junctions were shown to contain the gap junction protein Cx43.

Concise Review: Dental Pulp Stem Cells: A Novel Cell Therapy for Retinal and Central Nervous System Repair.

PubMed

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

2017-01-01

Dental pulp stem cells (DPSC) are neural crest-derived ecto-mesenchymal stem cells that can relatively easily and non-invasively be isolated from the dental pulp of extracted postnatal and adult teeth. Accumulating evidence suggests that DPSC have great promise as a cellular therapy for central nervous system (CNS) and retinal injury and disease. The mode of action by which DPSC confer therapeutic benefit may comprise multiple pathways, in particular, paracrine-mediated processes which involve a wide array of secreted trophic factors and is increasingly regarded as the principal predominant mechanism. In this concise review, we present the current evidence for the use of DPSC to repair CNS damage, including recent findings on retinal ganglion cell neuroprotection and regeneration in optic nerve injury and glaucoma. Stem Cells 2017;35:61-67. © 2016 AlphaMed Press.

Types of Stem Cells

MedlinePlus

... Cell Glossary Search Toggle Nav Types of Stem Cells Stem cells are the foundation from which all ... About Stem Cells > Types of Stem Cells Stem cells Stem cells are the foundation for every organ ...

Generation of Spinal Motor Neurons from Human Pluripotent Stem Cells.

PubMed

Santos, David P; Kiskinis, Evangelos

2017-01-01

Human embryonic stem cells (ESCs) are characterized by their unique ability to self-renew indefinitely, as well as to differentiate into any cell type of the human body. Induced pluripotent stem cells (iPSCs) share these salient characteristics with ESCs and can easily be generated from any given individual by reprogramming somatic cell types such as fibroblasts or blood cells. The spinal motor neuron (MN) is a specialized neuronal subtype that synapses with muscle to control movement. Here, we present a method to generate functional, postmitotic, spinal motor neurons through the directed differentiation of ESCs and iPSCs by the use of small molecules. These cells can be utilized to study the development and function of human motor neurons in healthy and disease states.

Keratin K15 as a Biomarker of Epidermal Stem Cells

PubMed Central

Bose, Amrita; Teh, Muy-Teck; Mackenzie, Ian C.; Waseem, Ahmad

2013-01-01

Keratin 15 (K15) is type I keratin protein co-expressed with the K5/K14 pair present in the basal keratinocytes of all stratified epithelia. Although it is a minor component of the cytoskeleton with a variable expression pattern, nonetheless its expression has been reported as a stem cell marker in the bulge of hair follicles. Conversely, suprabasal expression of K15 has also been reported in both normal and diseased tissues, which is inconsistent with its role as a stem cell marker. Our recently published work has given evidence of the molecular pathways that seem to control the expression of K15 in undifferentiated and differentiated cells. In this article, we have critically reviewed the published work to establish the reliability of K15 as an epidermal stem cell marker. PMID:24071939

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

PubMed

Aleksandrova, M A; Marey, M V

2015-01-01

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

N-cadherin adhesive interactions modulate matrix mechanosensing and fate commitment of mesenchymal stem cells

NASA Astrophysics Data System (ADS)

Cosgrove, Brian D.; Mui, Keeley L.; Driscoll, Tristan P.; Caliari, Steven R.; Mehta, Kush D.; Assoian, Richard K.; Burdick, Jason A.; Mauck, Robert L.

2016-12-01

During mesenchymal development, the microenvironment gradually transitions from one that is rich in cell-cell interactions to one that is dominated by cell-ECM (extracellular matrix) interactions. Because these cues cannot readily be decoupled in vitro or in vivo, how they converge to regulate mesenchymal stem cell (MSC) mechanosensing is not fully understood. Here, we show that a hyaluronic acid hydrogel system enables, across a physiological range of ECM stiffness, the independent co-presentation of the HAVDI adhesive motif from the EC1 domain of N-cadherin and the RGD adhesive motif from fibronectin. Decoupled presentation of these cues revealed that HAVDI ligation (at constant RGD ligation) reduced the contractile state and thereby nuclear YAP/TAZ localization in MSCs, resulting in altered interpretation of ECM stiffness and subsequent changes in downstream cell proliferation and differentiation. Our findings reveal that, in an evolving developmental context, HAVDI/N-cadherin interactions can alter stem cell perception of the stiffening extracellular microenvironment.

Proliferation and differentiation of direct co-culture of bone marrow mesenchymal stem cells and pigmented cells from the ciliary margin

PubMed Central

Li, Yan; He, Xinzheng; Li, Jun; Ni, Fangfang; Sun, Qingqing; Zhou, Yan

2017-01-01

Damage of retinal ganglion cells (RGCs) is the major consequence of glaucoma and regeneration of RGCs is extremely difficult once the damage has occurred. Retinal stem cells (RSCs) are considered an ideal choice for RGC regeneration. Pigmented cells from the ciliary margin (PCMs) have great retinal differentiation potential and may be an ideal RSC candidate. However, the ciliary margin is too small, so the number of cells that can be obtained is limited. Bone marrow-derived mesenchymal stem cells (BMMSCs) are another type of stem cell that have been previously investigated for RGC regeneration. BMMSCs expand sufficiently, whereas the retinal differentiation of BMMSCs is insufficient. The aim of the present study was to investigate whether the co-culture of PCMs and BMMSCs may combine the advantages of both cell types to establish a novel and effective stem cell source for RGC regeneration. Primary rat PCMs and BMMSCs were isolated and co-cultured. Cell growth was observed by an inverted microscope and proliferation was monitored by an MTT assay. Cell cycle analysis was performed by using a flow cytometer, while the expression of the photoreceptor-specific homeobox gene (cone-rod homeobox, Crx) was determined by reverse transcription-quantitative polymerase chain reaction and western blot analysis. In addition, retinal differentiation was confirmed by immunofluorescence staining of major markers of retinal differentiation, including rhodopsin, visual system homeobox 2 and heparin sulfate. The co-cultured cells expanded successfully, in a similar way to BMMSCs. In addition, the expression of Crx and retinal markers were significantly upregulated following BMMSC and PCM co-culture. The results of the present study demonstrated that the co-culture of BMMSCs and PCMs may be used as a source of RSCs. PMID:28440470

Assessment of stem cell differentiation based on genome-wide expression profiles.

PubMed

Godoy, Patricio; Schmidt-Heck, Wolfgang; Hellwig, Birte; Nell, Patrick; Feuerborn, David; Rahnenführer, Jörg; Kattler, Kathrin; Walter, Jörn; Blüthgen, Nils; Hengstler, Jan G

2018-07-05

In recent years, protocols have been established to differentiate stem and precursor cells into more mature cell types. However, progress in this field has been hampered by difficulties to assess the differentiation status of stem cell-derived cells in an unbiased manner. Here, we present an analysis pipeline based on published data and methods to quantify the degree of differentiation and to identify transcriptional control factors explaining differences from the intended target cells or tissues. The pipeline requires RNA-Seq or gene array data of the stem cell starting population, derived 'mature' cells and primary target cells or tissue. It consists of a principal component analysis to represent global expression changes and to identify possible problems of the dataset that require special attention, such as: batch effects; clustering techniques to identify gene groups with similar features; over-representation analysis to characterize biological motifs and transcriptional control factors of the identified gene clusters; and metagenes as well as gene regulatory networks for quantitative cell-type assessment and identification of influential transcription factors. Possibilities and limitations of the analysis pipeline are illustrated using the example of human embryonic stem cell and human induced pluripotent cells to generate 'hepatocyte-like cells'. The pipeline quantifies the degree of incomplete differentiation as well as remaining stemness and identifies unwanted features, such as colon- and fibroblast-associated gene clusters that are absent in real hepatocytes but typically induced by currently available differentiation protocols. Finally, transcription factors responsible for incomplete and unwanted differentiation are identified. The proposed method is widely applicable and allows an unbiased and quantitative assessment of stem cell-derived cells.This article is part of the theme issue 'Designer human tissue: coming to a lab near you'. © 2018 The Author(s).

Isolation and Propagation of Mesenchymal Stem Cells from the Lacrimal Gland

PubMed Central

You, Samantha; Kublin, Claire L.; Avidan, Orna; Miyasaki, David

2011-01-01

Purpose. Previously, it was reported that the murine lacrimal gland is capable of repair after experimentally induced injury and that the number of stem/progenitor cells was increased during the repair phase (2–3 days after injury). The aim of the present study was to determine whether these cells can be isolated from the lacrimal gland and propagated in vitro. Methods. Lacrimal gland injury was induced by injection of interleukin (IL)-1, and injection of saline vehicle served as control. Two and half days after injection, the lacrimal glands were removed and used to prepare explants or acinar cells for tissue culture. Cells derived from the explants and the acinar cells were grown in DMEM supplemented with 10% fetal bovine serum. Cells were stained for the stem cells markers, nestin, vimentin, ABCG2, and Sca-1. Cell proliferation was measured using an antibody against Ki67 or a cell-counting kit. The adipogenic capability of these cells was also tested in vitro. Results. Results show that nestin-positive cells can be isolated from IL-1–injected, but not saline-injected, lacrimal glands. A population of nestin-positive cells was also positive for vimentin, an intermediate filament protein expressed by mesenchymal cells. In addition, cultured cells expressed two other markers of stem cells, ABCG2 and Sca-1. These cells proliferated in vitro and can be induced to form adipocytes, attesting to their mesenchymal stem cell property. Conclusions. Murine lacrimal glands contain mesenchymal stem cells that seem to play a pivotal role in tissue repair. PMID:21178145

Publishing SNP genotypes of human embryonic stem cell lines: policy statement of the International Stem Cell Forum Ethics Working Party.

PubMed

Knoppers, Bartha M; Isasi, Rosario; Benvenisty, Nissim; Kim, Ock-Joo; Lomax, Geoffrey; Morris, Clive; Murray, Thomas H; Lee, Eng Hin; Perry, Margery; Richardson, Genevra; Sipp, Douglas; Tanner, Klaus; Wahlström, Jan; de Wert, Guido; Zeng, Fanyi

2011-09-01

Novel methods and associated tools permitting individual identification in publicly accessible SNP databases have become a debatable issue. There is growing concern that current technical and ethical safeguards to protect the identities of donors could be insufficient. In the context of human embryonic stem cell research, there are no studies focusing on the probability that an hESC line donor could be identified by analyzing published SNP profiles and associated genotypic and phenotypic information. We present the International Stem Cell Forum (ISCF) Ethics Working Party's Policy Statement on "Publishing SNP Genotypes of Human Embryonic Stem Cell Lines (hESC)". The Statement prospectively addresses issues surrounding the publication of genotypic data and associated annotations of hESC lines in open access databases. It proposes a balanced approach between the goals of open science and data sharing with the respect for fundamental bioethical principles (autonomy, privacy, beneficence, justice and research merit and integrity).

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

PubMed

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

2014-01-03

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

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

PubMed

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

2017-01-01

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

Diabetes-Induced Dysfunction of Mitochondria and Stem Cells in Skeletal Muscle and the Nervous System

PubMed Central

Fujimaki, Shin; Kuwabara, Tomoko

2017-01-01

Diabetes mellitus is one of the most common metabolic diseases spread all over the world, which results in hyperglycemia caused by the breakdown of insulin secretion or insulin action or both. Diabetes has been reported to disrupt the functions and dynamics of mitochondria, which play a fundamental role in regulating metabolic pathways and are crucial to maintain appropriate energy balance. Similar to mitochondria, the functions and the abilities of stem cells are attenuated under diabetic condition in several tissues. In recent years, several studies have suggested that the regulation of mitochondria functions and dynamics is critical for the precise differentiation of stem cells. Importantly, physical exercise is very useful for preventing the diabetic alteration by improving the functions of both mitochondria and stem cells. In the present review, we provide an overview of the diabetic alterations of mitochondria and stem cells and the preventive effects of physical exercise on diabetes, focused on skeletal muscle and the nervous system. We propose physical exercise as a countermeasure for the dysfunction of mitochondria and stem cells in several target tissues under diabetes complication and to improve the physiological function of patients with diabetes, resulting in their quality of life being maintained. PMID:29036909

Diabetes-Induced Dysfunction of Mitochondria and Stem Cells in Skeletal Muscle and the Nervous System.

PubMed

Fujimaki, Shin; Kuwabara, Tomoko

2017-10-14

Diabetes mellitus is one of the most common metabolic diseases spread all over the world, which results in hyperglycemia caused by the breakdown of insulin secretion or insulin action or both. Diabetes has been reported to disrupt the functions and dynamics of mitochondria, which play a fundamental role in regulating metabolic pathways and are crucial to maintain appropriate energy balance. Similar to mitochondria, the functions and the abilities of stem cells are attenuated under diabetic condition in several tissues. In recent years, several studies have suggested that the regulation of mitochondria functions and dynamics is critical for the precise differentiation of stem cells. Importantly, physical exercise is very useful for preventing the diabetic alteration by improving the functions of both mitochondria and stem cells. In the present review, we provide an overview of the diabetic alterations of mitochondria and stem cells and the preventive effects of physical exercise on diabetes, focused on skeletal muscle and the nervous system. We propose physical exercise as a countermeasure for the dysfunction of mitochondria and stem cells in several target tissues under diabetes complication and to improve the physiological function of patients with diabetes, resulting in their quality of life being maintained.

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

PubMed

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

2016-07-01

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

Depolarization Alters Phenotype, Maintains Plasticity of Predifferentiated Mesenchymal Stem Cells

PubMed Central

Sundelacruz, Sarah; Levin, Michael

2013-01-01

Although adult stem cell transplantation has been implemented as a therapy for tissue repair, it is limited by the availability of functional adult stem cells. A potential approach to generate stem and progenitor cells may be to modulate the differentiated status of somatic cells. Therefore, there is a need for a better understanding of how the differentiated phenotype of mature cells is regulated. We hypothesize that bioelectric signaling plays an important role in the maintenance of the differentiated state, as it is a functional regulator of the differentiation process in various cells and tissues. In this study, we asked whether the mature phenotype of osteoblasts and adipocytes derived from human mesenchymal stem cells (hMSCs) could be altered by modulation of their membrane potential. hMSC-derived osteoblasts and adipocytes were depolarized by treatment with ouabain, a Na+/K+ ATPase inhibitor, or by treatment with high concentrations of extracellular K+. To characterize the effect of voltage modulation on the differentiated state, the depolarized cells were evaluated for (1) the loss of differentiation markers; (2) the up-regulation of stemness markers and stem properties; and (3) differences in gene expression profiles in response to voltage modulation. hMSC-derived osteoblasts and adipocytes exhibited significant down-regulation of bone and fat tissue markers in response to depolarization, despite the presence of differentiation-inducing soluble factors, suggesting that bioelectric signaling overrides biochemical signaling in the maintenance of cell state. Suppression of the osteoblast or adipocyte phenotype was not accompanied by up-regulation of genes associated with the stem state. Thus, depolarization does not activate the stem cell genetic signature and, therefore, does not induce a full reprogramming event. However, after transdifferentiating the depolarized cells to evaluate for multi-lineage potential, depolarized osteoblasts demonstrated improved ability to achieve correct adipocyte morphology compared with nondepolarized osteoblasts. The present study thus demonstrates that depolarization reduces the differentiated phenotype of hMSC-derived cells and improves their transdifferentiation capacity, but does not restore a stem-like genetic profile. Through global transcript profiling of depolarized osteoblasts, we identified pathways that may mediate the effects of voltage signaling on cell state, which will require a detailed mechanistic inquiry in future studies. PMID:23738690

What is a stem cell?

PubMed

Slack, Jonathan M W

2018-05-15

The historical roots of the stem cell concept are traced with respect to its usage in embryology and in hematology. The modern consensus definition of stem cells, comprising both pluripotent stem cells in culture and tissue-specific stem cells in vivo, is explained and explored. Methods for identifying stem cells are discussed with respect to cell surface markers, telomerase, label retention and transplantability, and properties of the stem cell niche are explored. The CreER method for identifying stem cells in vivo is explained, as is evidence in favor of a stochastic rather than an obligate asymmetric form of cell division. In conclusion, it is found that stem cells do not possess any unique and specific molecular markers; and stem cell behavior depends on the environment of the cell as well as the stem cell's intrinsic qualities. Furthermore, the stochastic mode of division implies that stem cell behavior is a property of a cell population not of an individual cell. In this sense, stem cells do not exist in isolation but only as a part of multicellular system. This article is categorized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches Adult Stem Cells, Tissue Renewal, and Regeneration > Methods and Principles Adult Stem Cells, Tissue Renewal, and Regeneration > Environmental Control of Stem Cells. © 2018 Wiley Periodicals, Inc.

Safe and efficient method for cryopreservation of human induced pluripotent stem cell-derived neural stem and progenitor cells by a programmed freezer with a magnetic field.

PubMed

Nishiyama, Yuichiro; Iwanami, Akio; Kohyama, Jun; Itakura, Go; Kawabata, Soya; Sugai, Keiko; Nishimura, Soraya; Kashiwagi, Rei; Yasutake, Kaori; Isoda, Miho; Matsumoto, Morio; Nakamura, Masaya; Okano, Hideyuki

2016-06-01

Stem cells represent a potential cellular resource in the development of regenerative medicine approaches to the treatment of pathologies in which specific cells are degenerated or damaged by genetic abnormality, disease, or injury. Securing sufficient supplies of cells suited to the demands of cell transplantation, however, remains challenging, and the establishment of safe and efficient cell banking procedures is an important goal. Cryopreservation allows the storage of stem cells for prolonged time periods while maintaining them in adequate condition for use in clinical settings. Conventional cryopreservation systems include slow-freezing and vitrification both have advantages and disadvantages in terms of cell viability and/or scalability. In the present study, we developed an advanced slow-freezing technique using a programmed freezer with a magnetic field called Cells Alive System (CAS) and examined its effectiveness on human induced pluripotent stem cell-derived neural stem/progenitor cells (hiPSC-NS/PCs). This system significantly increased cell viability after thawing and had less impact on cellular proliferation and differentiation. We further found that frozen-thawed hiPSC-NS/PCs were comparable with non-frozen ones at the transcriptome level. Given these findings, we suggest that the CAS is useful for hiPSC-NS/PCs banking for clinical uses involving neural disorders and may open new avenues for future regenerative medicine. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Mesenchymal Stem Cell-Derived Factors Restore Function to Human Frataxin-Deficient Cells.

PubMed

Kemp, Kevin; Dey, Rimi; Cook, Amelia; Scolding, Neil; Wilkins, Alastair

2017-08-01

Friedreich's ataxia is an inherited neurological disorder characterised by mitochondrial dysfunction and increased susceptibility to oxidative stress. At present, no therapy has been shown to reduce disease progression. Strategies being trialled to treat Friedreich's ataxia include drugs that improve mitochondrial function and reduce oxidative injury. In addition, stem cells have been investigated as a potential therapeutic approach. We have used siRNA-induced knockdown of frataxin in SH-SY5Y cells as an in vitro cellular model for Friedreich's ataxia. Knockdown of frataxin protein expression to levels detected in patients with the disorder was achieved, leading to decreased cellular viability, increased susceptibility to hydrogen peroxide-induced oxidative stress, dysregulation of key anti-oxidant molecules and deficiencies in both cell proliferation and differentiation. Bone marrow stem cells are being investigated extensively as potential treatments for a wide range of neurological disorders, including Friedreich's ataxia. The potential neuroprotective effects of bone marrow-derived mesenchymal stem cells were therefore studied using our frataxin-deficient cell model. Soluble factors secreted by mesenchymal stem cells protected against cellular changes induced by frataxin deficiency, leading to restoration in frataxin levels and anti-oxidant defences, improved survival against oxidative stress and stimulated both cell proliferation and differentiation down the Schwann cell lineage. The demonstration that mesenchymal stem cell-derived factors can restore cellular homeostasis and function to frataxin-deficient cells further suggests that they may have potential therapeutic benefits for patients with Friedreich's ataxia.

Accelerated generation of oligodendrocyte progenitor cells from human induced pluripotent stem cells by forced expression of Sox10 and Olig2.

PubMed

Li, Pengyan; Li, Mo; Tang, Xihe; Wang, Shuyan; Zhang, Y Alex; Chen, Zhiguo

2016-11-01

Oligodendrocyte progenitor cells (OPCs) hold great promise for treatment of dysmyelinating disorders, such as multiple sclerosis and cerebral palsy. Recent studies on generation of human OPCs mainly use human embryonic stem cells (hESCs) or neural stem cells (NSCs) as starter cell sources for the differentiation process. However, NSCs are restricted in availability and the present method for generation of oligodendrocytes (OLs) from ESCs often requires a lengthy period of time. Here, we demonstrated a protocol to efficiently derive OPCs from human induced pluripotent stem cells (hiPSCs) by forced expression of two transcription factors (2TFs), Sox10 and Olig2. With this method, PDGFRα + OPCs can be obtained in 14 days and O4 + OPCs in 56 days. Furthermore, OPCs may be able to differentiate to mature OLs that could ensheath axons when co-cultured with rat cortical neurons. The results have implications in the development of autologous cell therapies.

Mesenchymal stem cells: biological characteristics and potential clinical applications.

PubMed

Kassem, Moustapha

2004-01-01

Mesenchymal stem cells (MSC) are clonogenic, non-hematpoietic stem cells present in the bone marrow and are able to differentiate into multiple mesoderm-type cell lineages, for example, osteoblasts, chondrocytes, endothelial-cells and also non-mesoderm-type lineages, for example, neuronal-like cells. Several methods are currently available for isolation of the MSC based on their physical and physico-chemical characteristics, for example, adherence to plastics or other extracellular matrix components. Because of the ease of their isolation and their extensive differentiation potential, MSC are among the first stem cell types to be introduced in the clinic. Several studies have demonstrated the possible use of MSC in systemic transplantation for systemic diseases, local implantation for local tissue defects, as a vehicle for genes in gene therapy protocols or to generate transplantable tissues and organs in tissue engineering protocols. Before their widespread use in therapy, methods allowing the generation of large number of cells without affecting their differentiation potential as well as technologies that overcome immunological rejection (in case allogenic transplantation) must be developed.

Alginate Microcapsules Incorporating Hyaluronic Acid Recreate Closer in Vivo Environment for Mesenchymal Stem Cells.

PubMed

Cañibano-Hernández, Alberto; Saenz Del Burgo, Laura; Espona-Noguera, Albert; Orive, Gorka; Hernández, Rosa M; Ciriza, Jesús; Pedraz, Jose Luis

2017-07-03

The potential clinical application of alginate cell microencapsulation has advanced enormously during the past decade. However, the 3D environment created by alginate beads does not mimic the natural extracellular matrix surrounding cells in vivo, responsible of cell survival and functionality. As one of the most frequent macromolecules present in the extracellular matrix is hyaluronic acid, we have formed hybrid beads with alginate and hyaluronic acid recreating a closer in vivo cell environment. Our results show that 1% alginate-0.25% hyaluronic acid microcapsules retain 1.5% alginate physicochemical properties. Moreover, mesenchymal stem cells encapsulated in these hybrid beads show enhanced viability therapeutic protein release and mesenchymal stem cells' potential to differentiate into chondrogenic lineage. Although future studies with additional proteins need to be done in order to approach even more the extracellular matrix features, we have shown that hyaluronic acid protects alginate encapsulated mesenchymal stem cells by providing a niche-like environment and remaining them competent as a sustainable drug delivery system.

Characterization of stem cells in Dupuytren's disease.

PubMed

Hindocha, S; Iqbal, S A; Farhatullah, S; Paus, R; Bayat, A

2011-02-01

Dupuytren's disease (DD) is a common fibroproliferative disease of unknown origin. The source of abnormal cells leading to DD formation remains underexplored. In addition to fascia, palmar skin and fat-derived cells may be a potential source of cells causing DD. This study aimed to profile haematopoietic and mesenchymal stem cells in different DD tissue components compared with tissue removed at carpal tunnel surgery (control). Biopsies were taken from the diseased cord, nodule, perinodular fat and skin overlying the nodule of ten patients with DD and compared with control tissue from seven patients having surgery for carpal tunnel syndrome. Fluorescence-activated cell sorting (FACS), immunohistochemistry and quantitative real-time polymerase chain reaction (QRT-PCR) were used to identify expression of selected stem cell markers. FACS and QRT-PCR analysis identified the highest RNA expression and number of cells positive for adipocyte stem cell markers (CD13 and CD29) in the DD nodule in comparison with carpal tunnel control tissue (P = 0·053). CD34 RNA was overexpressed, and a higher percentage of these cells was present in DD skin compared with carpal tunnel skin (P = 0·001). Each structural component of DD (cord, nodule, perinodular fat and skin) had distinct stem cell populations. These findings support the hypothesis that DD may result from mesenchymal progenitor cell expansion.

Mesenchymal Stem Cells: New Players in Retinopathy Therapy

PubMed Central

Rajashekhar, Gangaraju

2014-01-01

Retinopathies in human and animal models have shown to occur through loss of pericytes resulting in edema formation, excessive immature retinal angiogenesis, and neuronal apoptosis eventually leading to blindness. In recent years, the concept of regenerating terminally differentiated organs with a cell-based therapy has evolved. The cells used in these approaches are diverse and include tissue-specific endogenous stem cells, endothelial progenitor (EPC), embryonic stem cells, induced pluripotent stem cells (iPSC) and mesenchymal stem cells (MSC). Recently, MSC derived from the stromal fraction of adipose tissue have been shown to possess pluripotent differentiation potential in vitro. These adipose stromal cells (ASC) have been differentiated in a number of laboratories to osteogenic, myogenic, vascular, and adipocytic cell phenotypes. In vivo, ASC have been shown to have functional and phenotypic overlap with pericytes lining microvessels in adipose tissues. Furthermore, these cells either in paracrine mode or physical proximity with endothelial cells, promoted angiogenesis, improved ischemia–reperfusion, protected from myocardial infarction, and were neuroprotective. Owing to the easy isolation procedure and abundant supply, fat-derived ASC are a more preferred source of autologous mesenchymal cells compared to bone marrow MSC. In this review, we present evidence that these readily available ASC from minimally invasive liposuction will facilitate translation of ASC research into patients with retinal diseases in the near future. PMID:24795699

Somatic stem cells and the kinetics of mutagenesis and carcinogenesis

PubMed Central

Cairns, John

2002-01-01

There is now strong experimental evidence that epithelial stem cells arrange their sister chromatids at mitosis such that the same template DNA strands stay together through successive divisions; DNA labeled with tritiated thymidine in infancy is still present in the stem cells of adult mice even though these cells are incorporating (and later losing) bromodeoxyuridine [Potten, C. S., Owen, G., Booth, D. & Booth, C. (2002) J. Cell Sci.115, 2381–2388]. But a cell that preserves “immortal strands” will avoid the accumulation of replication errors only if it inhibits those pathways for DNA repair that involve potentially error-prone resynthesis of damaged strands, and this appears to be a property of intestinal stem cells because they are extremely sensitive to the lethal effects of agents that damage DNA. It seems that the combination, in the stem cell, of immortal strands and the choice of death rather than error-prone repair makes epithelial stem cell systems resistant to short exposures to DNA-damaging agents, because the stem cell accumulates few if any errors, and any errors made by the daughters are destined to be discarded. This paper discusses these issues and shows that they lead to a model that explains the strange kinetics of mutagenesis and carcinogenesis in adult mammalian tissues. Coincidentally, the model also can explain why cancers arise even though the spontaneous mutation rate of differentiated mammalian cells is not high enough to generate the multiple mutations needed to form a cancer and why loss of nucleotide-excision repair does not significantly increase the frequency of the common internal cancers. PMID:12149477

Therapeutic implications of an enriched cancer stem-like cell population in a human osteosarcoma cell line

PubMed Central

2012-01-01

Background Osteosarcoma is a bone-forming tumor of mesenchymal origin that presents a clinical pattern that is consistent with the cancer stem cell model. Cells with stem-like properties (CSCs) have been identified in several tumors and hypothesized as the responsible for the relative resistance to therapy and tumor relapses. In this study, we aimed to identify and characterize CSCs populations in a human osteosarcoma cell line and to explore their role in the responsiveness to conventional therapies. Methods CSCs were isolated from the human MNNG/HOS cell line using the sphere formation assay and characterized in terms of self-renewal, mesenchymal stem cell properties, expression of pluripotency markers and ABC transporters, metabolic activity and tumorigenicity. Cell's sensitivity to conventional chemotherapeutic agents and to irradiation was analyzed and related with cell cycle-induced alterations and apoptosis. Results The isolated CSCs were found to possess self-renewal and multipotential differentiation capabilities, express markers of pluripotent embryonic stem cells Oct4 and Nanog and the ABC transporters P-glycoprotein and BCRP, exhibit low metabolic activity and induce tumors in athymic mice. Compared with parental MNNG/HOS cells, CSCs were relatively more resistant to both chemotherapy and irradiation. None of the treatments have induced significant cell-cycle alterations and apoptosis in CSCs. Conclusions MNNG/HOS osteosarcoma cells contain a stem-like cell population relatively resistant to conventional chemotherapeutic agents and irradiation. This resistant phenotype appears to be related with some stem features, namely the high expression of the drug efflux transporters P-glycoprotein and BCRP and their quiescent nature, which may provide a biological basis for resistance to therapy and recurrence commonly observed in osteosarcoma. PMID:22475227

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

PubMed

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.

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.

Cell Patterning Chip for Controlling the Stem Cell Microenvironment

PubMed Central

Rosenthal, Adam; Macdonald, Alice; Voldman, Joel

2007-01-01

Cell-cell signaling is an important component of the stem cell microenvironment, affecting both differentiation and self-renewal. However, traditional cell-culture techniques do not provide precise control over cell-cell interactions, while existing cell patterning technologies are limited when used with proliferating or motile cells. To address these limitations, we created the Bio Flip Chip (BFC), a microfabricated polymer chip containing thousands of microwells, each sized to trap down to a single stem cell. We have demonstrated the functionality of the BFC by patterning a 50×50 grid of murine embryonic stem cells (mESCs), with patterning efficiencies > 75%, onto a variety of substrates – a cell-culture dish patterned with gelatin, a 3-D substrate, and even another layer of cells. We also used the BFC to pattern small groups of cells, with and without cell-cell contact, allowing incremental and independent control of contact-mediated signaling. We present quantitative evidence that cell-cell contact plays an important role in depressing mESC colony formation, and show that E-cadherin is involved in this negative regulatory pathway. Thus, by allowing exquisite control of the cellular microenvironment, we provide a technology that enables new applications in tissue engineering and regenerative medicine. PMID:17434582

Loss of quiescence and self-renewal capacity of hematopoietic stem cell in an in vitro leukemic niche.

PubMed

Vanegas, Natalia-Del Pilar; Vernot, Jean-Paul

2017-01-01

Leukemic and mesenchymal stem cells interact in the leukemic microenvironment and affect each other differently. This interplay has also important implications for the hematopoietic stem cell (HSC) biology and function. This study evaluated human HSC self-renewal potential and quiescence in an in vitro leukemic niche without leukemic cells. A leukemic niche was established by co-culturing mesenchymal stem cells with a fresh conditioned medium obtained from a leukemic (REH) cell line. After 3 days, the REH-conditioned medium was removed and freshly isolated CD34+ at a density of up to 100,000 cells/ml were added to the leukemic niche. CD34+ cell evaluations (cell cycle, self-renewal gene expression and migration capacity) were performed after 3 further days of co-culture. Additionally, we preliminary investigated the soluble factors present in the leukemic niche and their effect on the mesenchymal stem cells. Statistical significance was assessed by Student's t test or the nonparametric test Kolmogorov-Smirnov. By co-culturing normal mesenchymal stem cells with the REH-conditioned medium we showed that hematopoietic stem cells, normally in a quiescent state, enter cell cycle and proliferate. This loss of quiescence was accompanied by an increased expression of Ki-67 and c-Myc, two well-known cell proliferation-associated markers. Two central regulators of quiescence GATA2 and p53 were also down regulated. Importantly, two genes involved in HSC self-renewal, Klf4 and the histone-lysine N -methyltransferase enzyme Ezh2, were severely affected. On the contrary, c-Kit expression, the stem cell factor receptor, was upregulated in hematopoietic stem cells when compared to the normal niche. Interestingly, mesenchymal stem cells incubated with the REH-conditioned medium stopped growing, showed a flattened morphology with the appearance of small vacuoles, and importantly, became positive for the senescence-associated beta-galactosidase activity. Evaluation of the leukemic-conditioned medium showed increased IL-6 and IL-8, suggesting that these cytokines could be responsible for the observed changes. Our results showed that quiescence and self-renewal are severely affected in this leukemic niche. This in vitro leukemic niche, established without leukemic cells, will facilitate HSC gene expression evaluation and the development of therapeutic agents aimed to neutralize soluble factors and the cell signaling pathways involved in HSC alterations.

Rethinking differentiation: Stem cells, regeneration, and plasticity

PubMed Central

Alvarado, Alejandro Sánchez; Yamanaka, Shinya

2014-01-01

Cell differentiation is an essential process for the development, growth, reproduction and longevity of all multicellular organisms, and its regulation has been the focus of intense investigation for the past 4 decades. The study of natural and induced stem cells has ushered an age of re-examination of what it means to be a stem or a differentiated cell. Past and recent discoveries in plants and animals, as well as novel experimental manipulations are beginning to erode many of these established concepts, and are forcing a re-evaluation of the experimental systems and paradigms presently being used to explore these and other biological process. PMID:24679530

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

PubMed Central

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

2015-01-01

Neural stem cell (NSC)-based therapies offer potential for neural repair in central nervous system (CNS) inflammatory and degenerative disorders. Typically, these conditions present with multifocal CNS lesions making it impractical to inject NSCs locally, thus mandating optimization of vascular delivery of the cells to involved sites. Here, we analyzed NSCs for expression of molecular effectors of cell migration and found that these cells are natively devoid of E-selectin ligands. Using glycosyltransferase-programmed stereosubstitution (GPS), we glycan engineered the cell surface of NSCs (“GPS-NSCs”) with resultant enforced expression of the potent E-selectin ligand HCELL (hematopoietic cell E-/L-selectin ligand) and of an E-selectin-binding glycoform of neural cell adhesion molecule (“NCAM-E”). Following intravenous (i.v.) injection, short-term homing studies demonstrated that, compared with buffer-treated (control) NSCs, GPS-NSCs showed greater neurotropism. Administration of GPS-NSC significantly attenuated the clinical course of experimental autoimmune encephalomyelitis (EAE), with markedly decreased inflammation and improved oligodendroglial and axonal integrity, but without evidence of long-term stem cell engraftment. Notably, this effect of NSC is not a universal property of adult stem cells, as administration of GPS-engineered mouse hematopoietic stem/progenitor cells did not improve EAE clinical course. These findings highlight the utility of cell surface glycan engineering to boost stem cell delivery in neuroinflammatory conditions and indicate that, despite the use of a neural tissue-specific progenitor cell population, neural repair in EAE results from endogenous repair and not from direct, NSC-derived cell replacement. PMID:26153105

Regulation of stem cell-based therapies in Canada: current issues and concerns.

PubMed

von Tigerstrom, Barbara; Nguyen, Thu Minh; Knoppers, Bartha Maria

2012-09-01

Stem cell therapies offer enormous potential for the treatment of a wide range of diseases and conditions. Despite the excitement over such advances, regulators are faced with the challenge of determining criteria to ensure stem cells and their products are safe and effective for human use. However, stem cell-based products and therapies present unique regulatory challenges because standard drug development models do not wholly apply given the complexity and diversity of these products and therapies. As a result, regulatory requirements are often unclear and ambiguous creating unnecessary barriers for research. In order to better understand the barriers that might affect Canadian stem cell researchers, we sought feedback from stakeholders regarding areas of uncertainty or concern about existing regulatory oversight of cell therapies. A selection of Canadian researchers and clinicians working in the area of stem cell research were interviewed to assess certain key questions: 1) whether current regulatory requirements are easily accessible and well understood; 2) whether regulatory requirements create important challenges or barriers; and 3) whether there is a need for further guidance on the issue. The results of this survey are summarized and compared to issues and concerns experienced in other countries, as reported in the literature, to identify challenges which may be on the horizon and to provide possible solutions for regulatory reform.

The low chamber pancreatic cancer cells had stem-like characteristics in modified transwell system: is it a novel method to identify and enrich cancer stem-like cells?

PubMed

Wang, Dongqing; Zhu, Haitao; Liu, Yanfang; Liu, Qing; Xie, Xiaodong; Zhou, Yuepeng; Zhang, Lirong; Zhu, Yan; Zhang, Zhijian; Su, Zhaoliang

2014-01-01

Cancer stem cells (CSCs) or cancer-initiating cells (CICs) play an important role in tumor initiation, progression, metastasis, chemoresistance, and recurrence. It is important to construct an effective method to identify and isolate CSCs for biotherapy of cancer. During the past years, many researchers had paid more attention to it; however, this method was still on seeking. Therefore, compared to the former methods that were used to isolate the cancer stem cell, in the present study, we tried to use modified transwell system to isolate and enrich CSCs from human pancreatic cancer cell lines (Panc-1). Our results clearly showed that the lower chamber cells in modified transwell system were easily forming spheres; furthermore, these spheres expressed high levels of stem cell markers (CD133/CD44/CD24/Oct-4/ESA) and exhibited chemoresistance, underwent epithelial-to-mesenchymal transition (EMT), and possessed the properties of self-renewal in vitro and tumorigenicity in vivo. Therefore, we speculated that modified transwell assay system, as a rapid and effective method, can be used to isolate and enrich CSCs.

Neurite extension and neuronal differentiation of human induced pluripotent stem cell derived neural stem cells on polyethylene glycol hydrogels containing a continuous Young's Modulus gradient.

PubMed

Mosley, Matthew C; Lim, Hyun Ju; Chen, Jing; Yang, Yueh-Hsun; Li, Shenglan; Liu, Ying; Smith Callahan, Laura A

2017-03-01

Mechanotransduction in neural cells involves multiple signaling pathways that are not fully understood. Differences in lineage and maturation state are suggested causes for conflicting reports on neural cell mechanosensitivity. To optimize matrices for use in stem cell therapy treatments transplanting human induced pluripotent stem cell derived neural stem cells (hNSC) into lesions after spinal cord injury, the effects of Young's Modulus changes on hNSC behavior must be understood. The present study utilizes polyethylene glycol hydrogels containing a continuous gradient in Young's modulus to examine changes in the Young's Modulus of the culture substrate on hNSC neurite extension and neural differentiation. Changes in the Young's Modulus of the polyethylene glycol hydrogels was found to affect neurite extension and cellular organization on the matrices. hNSC cultured on 907 Pa hydrogels were found to extend longer neurites than hNSC cultured on other tested Young's Moduli hydrogels. The gene expression of β tubulin III and microtubule-associated protein 2 in hNSC was affected by changes in the Young's Modulus of the hydrogel. The combinatory method approach used in the present study demonstrates that hNSC are mechanosensitive and the matrix Young's Modulus should be a design consideration for hNSC transplant applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 824-833, 2017. © 2016 Wiley Periodicals, Inc.

The carbocyanine dye DiD labels in vitro and in vivo neural stem cells of the subventricular zone as well as myelinated structures following in vivo injection in the lateral ventricle.

PubMed

Carradori, Dario; Barreau, Kristell; Eyer, Joël

2016-02-01

Carbocyanines are fluorescent lipophilic cationic dyes used since the early 1980s as neuronal tracers. Several applications of these compounds have been developed thanks to their low cell toxicity, lateral diffusion within the cellular membranes, and good photostability. 1,1'-Dioctadecyl-3,3,3',3'-tetramethylindodicarbocyanine 4-chlorobenzenesulfonate (DiD) is an interesting component of this family because, in addition to the classic carbocyanine properties, it has a longer wavelength compared with its analogues. That makes DiD an excellent carbocyanine for labeling cells and tissues with significant intrinsic fluorescence. Drug encapsulation, drug delivery, and cellular transplantation are also fields using DiD-based systems where having detailed knowledge about its behavior as a single entity is important. Recently, promising studies concerned neural stem cells from the subventricular zone of the lateral ventricle in the brain (their natural niche) and their potential therapeutic use. Here, we show that DiD is able to label these stem cells in vitro and present basilar information concerning its pharmacokinetics, concentrations, and microscope protocols. Moreover, when DiD is injected in vivo in the cerebrospinal fluid present in the lateral ventricle of rat, it also labels stem cells as well as myelinated structures of the caudoputamen. This analysis provides a database to consult when planning experiments concerning DiD and neural stem cells from the subventricular zone. © 2015 Wiley Periodicals, Inc.

Evaluation of hematopoietic potential generated by transplantation of muscle-derived stem cells in mice.

PubMed

Farace, Francoise; Prestoz, Laetitita; Badaoui, Sabrina; Guillier, Martine; Haond, Celine; Opolon, Paule; Thomas, Jean-Leon; Zalc, Bernard; Vainchenker, William; Turhan, Ali G

2004-02-01

Muscle tissue of adult mice has been shown to contain stem cells with hematopoietic repopulation ability in vivo. To determine the functional characteristics of stem cells giving rise to this hematopoietic activity, we have performed hematopoietic reconstitution experiments by the use of muscle versus marrow transplantation in lethally irradiated mice and followed the fate of transplanted cells by Y-chimerism using PCR and fluorescence in situ hybridization (FISH) analysis. We report here that transplantation of murine muscle generate a major hematopoietic chimerism at the level of CFU-C, CFU-S, and terminally-differentiated cells in three generations of lethally irradiated mice followed up to 1 year after transplantation. This potential is totally abolished when muscle grafts were performed by the use of muscle from previously irradiated mice. As compared to marrow transplantation, muscle transplants were able to generate similar potencies to give rise to myeloid, T, B, and natural killer (NK) cells. Interestingly, marrow stem cells that have been generated in primary and then in secondary recipients were able to contribute efficiently to myofibers in the muscle tissue of tertiary recipients. Altogether, our data demonstrate that muscle-derived stem cells present a major hematopoietic repopulating ability with evidence of self-replication in vivo. They are radiation-sensitive and similar to marrow-derived stem cells in terms of their ability to generate multilineage hematopoiesis. Finally, our data demonstrate that muscle-derived hematopoietic stem cells do not lose their ability to contribute to myofiber generation after at least two rounds of serial transplantation, suggesting a potential that is probably equivalent to that generated by marrow transplantation.

Research Advancements in Porcine Derived Mesenchymal Stem Cells

PubMed Central

Bharti, Dinesh; Shivakumar, Sharath Belame; Subbarao, Raghavendra Baregundi; Rho, Gyu-Jin

2016-01-01

In the present era of stem cell biology, various animals such as Mouse, Bovine, Rabbit and Porcine have been tested for the efficiency of their mesenchymal stem cells (MSCs) before their actual use for stem cell based application in humans. Among them pigs have many similarities to humans in the form of organ size, physiology and their functioning, therefore they have been considered as a valuable model system for in vitro studies and preclinical assessments. Easy assessability, few ethical issues, successful MSC isolation from different origins like bone marrow, skin, umbilical cord blood, Wharton’s jelly, endometrium, amniotic fluid and peripheral blood make porcine a good model for stem cell therapy. Porcine derived MSCs (pMSCs) have shown greater in vitro differentiation and transdifferention potential towards mesenchymal lineages and specialized lineages such as cardiomyocytes, neurons, hepatocytes and pancreatic beta cells. Immunomodulatory and low immunogenic profiles as shown by autologous and heterologous MSCs proves them safe and appropriate models for xenotransplantation purposes. Furthermore, tissue engineered stem cell constructs can be of immense importance in relation to various osteochondral defects which are difficult to treat otherwise. Using pMSCs successful treatment of various disorders like Parkinson’s disease, cardiac ischemia, hepatic failure, has been reported by many studies. Here, in this review we highlight current research findings in the area of porcine mesenchymal stem cells dealing with their isolation methods, differentiation ability, transplantation applications and their therapeutic potential towards various diseases. PMID:26201864

Functionalized scaffolds to control dental pulp stem cell fate

PubMed Central

Piva, Evandro; Silva, Adriana F.; Nör, Jacques E.

2014-01-01

Emerging understanding about interactions between stem cells, scaffolds and morphogenic factors has accelerated translational research in the field of dental pulp tissue engineering. Dental pulp stem cells constitute a sub-population of cells endowed with self-renewal and multipotency. Dental pulp stem cells seeded in biodegradable scaffolds and exposed to dentin-derived morphogenic signals give rise to a pulp-like tissue capable of generating new dentin. Notably, dentin-derived proteins are sufficient to induce dental pulp stem cell differentiation into odontoblasts. Ongoing work is focused on developing ways of mobilizing dentin-derived proteins and disinfecting the root canal of necrotic teeth without compromising the morphogenic potential of these signaling molecules. On the other hand, dentin by itself does not appear to be capable of inducing endothelial differentiation of dental pulp stem cells, despite the well known presence of angiogenic factors in dentin. This is particularly relevant in the context of dental pulp tissue engineering in full root canals, where access to blood supply is limited to the apical foramina. To address this challenge, scientists are looking at ways to use the scaffold as a controlled release device for angiogenic factors. The aim of this manuscript is to present and discuss current strategies to functionalize injectable scaffolds and customize them for dental pulp tissue engineering. The long-term goal of this work is to develop stem cell-based therapies that enable the engineering of functional dental pulps capable of generating new tubular dentin in humans. PMID:24698691

Unravelling the mystery of stem/progenitor cells in human breast milk.

PubMed

Fan, Yiping; Chong, Yap Seng; Choolani, Mahesh A; Cregan, Mark D; Chan, Jerry K Y

2010-12-28

Mammary stem cells have been extensively studied as a system to delineate the pathogenesis and treatment of breast cancer. However, research on mammary stem cells requires tissue biopsies which limit the quantity of samples available. We have previously identified putative mammary stem cells in human breast milk, and here, we further characterised the cellular component of human breast milk. We identified markers associated with haemopoietic, mesenchymal and neuro-epithelial lineages in the cellular component of human breast milk. We found 2.6 ± 0.8% (mean ± SEM) and 0.7 ± 0.2% of the whole cell population (WCP) were found to be CD133+ and CD34+ respectively, 27.8 ± 9.1% of the WCP to be positive for Stro-1 through flow-cytometry. Expressions of neuro-ectodermal stem cell markers such as nestin and cytokeratin 5 were found through reverse-transcription polymerase chain reaction (RT-PCR), and in 4.17 ± 0.2% and 0.9 ± 0.2% of the WCP on flow-cytometry. We also established the presence of a side-population (SP) (1.8 ± 0.4% of WCP) as well as CD133+ cells (1.7 ± 0.5% of the WCP). Characterisation of the sorted SP and non-SP, CD133+ and CD133- cells carried out showed enrichment of CD326 (EPCAM) in the SP cells (50.6 ± 8.6 vs 18.1 ± 6.0, P-value  = 0.02). However, culture in a wide range of in vitro conditions revealed the atypical behaviour of stem/progenitor cells in human breast milk; in that if they are present, they do not respond to established culture protocols of stem/progenitor cells. The identification of primitive cell types within human breast milk may provide a non-invasive source of relevant mammary cells for a wide-range of applications; even the possibility of banking one's own stem cell for every breastfeeding woman.

Unravelling the Mystery of Stem/Progenitor Cells in Human Breast Milk

PubMed Central

Fan, Yiping; Chong, Yap Seng; Choolani, Mahesh A.; Cregan, Mark D.; Chan, Jerry K. Y.

2010-01-01

Background Mammary stem cells have been extensively studied as a system to delineate the pathogenesis and treatment of breast cancer. However, research on mammary stem cells requires tissue biopsies which limit the quantity of samples available. We have previously identified putative mammary stem cells in human breast milk, and here, we further characterised the cellular component of human breast milk. Methodology/Principal Findings We identified markers associated with haemopoietic, mesenchymal and neuro-epithelial lineages in the cellular component of human breast milk. We found 2.6±0.8% (mean±SEM) and 0.7±0.2% of the whole cell population (WCP) were found to be CD133+ and CD34+ respectively, 27.8±9.1% of the WCP to be positive for Stro-1 through flow-cytometry. Expressions of neuro-ectodermal stem cell markers such as nestin and cytokeratin 5 were found through reverse-transcription polymerase chain reaction (RT-PCR), and in 4.17±0.2% and 0.9±0.2% of the WCP on flow-cytometry. We also established the presence of a side-population (SP) (1.8±0.4% of WCP) as well as CD133+ cells (1.7±0.5% of the WCP). Characterisation of the sorted SP and non-SP, CD133+ and CD133- cells carried out showed enrichment of CD326 (EPCAM) in the SP cells (50.6±8.6 vs 18.1±6.0, P-value  = 0.02). However, culture in a wide range of in vitro conditions revealed the atypical behaviour of stem/progenitor cells in human breast milk; in that if they are present, they do not respond to established culture protocols of stem/progenitor cells. Conclusions/Significance The identification of primitive cell types within human breast milk may provide a non-invasive source of relevant mammary cells for a wide-range of applications; even the possibility of banking one's own stem cell for every breastfeeding woman. PMID:21203434

Differential marker expression by cultures rich in mesenchymal stem cells

PubMed Central

2013-01-01

Background Mesenchymal stem cells have properties that make them amenable to therapeutic use. However, the acceptance of mesenchymal stem cells in clinical practice requires standardized techniques for their specific isolation. To date, there are no conclusive marker (s) for the exclusive isolation of mesenchymal stem cells. Our aim was to identify markers differentially expressed between mesenchymal stem cell and non-stem cell mesenchymal cell cultures. We compared and contrasted the phenotype of tissue cultures in which mesenchymal stem cells are rich and rare. By initially assessing mesenchymal stem cell differentiation, we established that bone marrow and breast adipose cultures are rich in mesenchymal stem cells while, in our hands, foreskin fibroblast and olfactory tissue cultures contain rare mesenchymal stem cells. In particular, olfactory tissue cells represent non-stem cell mesenchymal cells. Subsequently, the phenotype of the tissue cultures were thoroughly assessed using immuno-fluorescence, flow-cytometry, proteomics, antibody arrays and qPCR. Results Our analysis revealed that all tissue cultures, regardless of differentiation potential, demonstrated remarkably similar phenotypes. Importantly, it was also observed that common mesenchymal stem cell markers, and fibroblast-associated markers, do not discriminate between mesenchymal stem cell and non-stem cell mesenchymal cell cultures. Examination and comparison of the phenotypes of mesenchymal stem cell and non-stem cell mesenchymal cell cultures revealed three differentially expressed markers – CD24, CD108 and CD40. Conclusion We indicate the importance of establishing differential marker expression between mesenchymal stem cells and non-stem cell mesenchymal cells in order to determine stem cell specific markers. PMID:24304471

Human embryonic stem cell therapies for neurodegenerative diseases.

PubMed

Tomaskovic-Crook, Eva; Crook, Jeremy M

2011-06-01

There is a renewed enthusiasm for the clinical translation of human embryonic stem (hES) cells. This is abetted by putative clinically-compliant strategies for hES cell maintenance and directed differentiation, greater understanding of and accessibility to cells through formal cell registries and centralized cell banking for distribution, the revised US government policy on funding hES cell research, and paradoxically the discovery of induced pluripotent stem (iPS) cells. Additionally, as we consider the constraints (practical and fiscal) of delivering cell therapies for global healthcare, the more efficient and economical application of allogeneic vs autologous treatments will bolster the clinical entry of hES cell derivatives. Neurodegenerative disorders such as Parkinson's disease are primary candidates for hES cell therapy, although there are significant hurdles to be overcome. The present review considers key advances and challenges to translating hES cells into novel therapies for neurodegenerative diseases, with special consideration given to Parkinson's disease and Alzheimer's disease. Importantly, despite the focus on degenerative brain disorders and hES cells, many of the issues canvassed by this review are relevant to systemic application of hES cells and other pluripotent stem cells such as iPS cells.

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

PubMed Central

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

2013-01-01

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

Modeling Inborn Errors of Hepatic Metabolism Using Induced Pluripotent Stem Cells.

PubMed

Pournasr, Behshad; Duncan, Stephen A

2017-11-01

Inborn errors of hepatic metabolism are because of deficiencies commonly within a single enzyme as a consequence of heritable mutations in the genome. Individually such diseases are rare, but collectively they are common. Advances in genome-wide association studies and DNA sequencing have helped researchers identify the underlying genetic basis of such diseases. Unfortunately, cellular and animal models that accurately recapitulate these inborn errors of hepatic metabolism in the laboratory have been lacking. Recently, investigators have exploited molecular techniques to generate induced pluripotent stem cells from patients' somatic cells. Induced pluripotent stem cells can differentiate into a wide variety of cell types, including hepatocytes, thereby offering an innovative approach to unravel the mechanisms underlying inborn errors of hepatic metabolism. Moreover, such cell models could potentially provide a platform for the discovery of therapeutics. In this mini-review, we present a brief overview of the state-of-the-art in using pluripotent stem cells for such studies. © 2017 American Heart Association, Inc.

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

PubMed

Atala, Anthony

2005-07-01

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

The quantitative proteomes of human-induced pluripotent stem cells and embryonic stem cells

PubMed Central

Munoz, Javier; Low, Teck Y; Kok, Yee J; Chin, Angela; Frese, Christian K; Ding, Vanessa; Choo, Andre; Heck, Albert J R

2011-01-01

Assessing relevant molecular differences between human-induced pluripotent stem cells (hiPSCs) and human embryonic stem cells (hESCs) is important, given that such differences may impact their potential therapeutic use. Controversy surrounds recent gene expression studies comparing hiPSCs and hESCs. Here, we present an in-depth quantitative mass spectrometry-based analysis of hESCs, two different hiPSCs and their precursor fibroblast cell lines. Our comparisons confirmed the high similarity of hESCs and hiPSCS at the proteome level as 97.8% of the proteins were found unchanged. Nevertheless, a small group of 58 proteins, mainly related to metabolism, antigen processing and cell adhesion, was found significantly differentially expressed between hiPSCs and hESCs. A comparison of the regulated proteins with previously published transcriptomic studies showed a low overlap, highlighting the emerging notion that differences between both pluripotent cell lines rather reflect experimental conditions than a recurrent molecular signature. PMID:22108792

Three-dimensional morphological imaging of human induced pluripotent stem cells by using low-coherence quantitative phase microscopy

NASA Astrophysics Data System (ADS)

Yamauchi, Toyohiko; Kakuno, Yumi; Goto, Kentaro; Fukami, Tadashi; Sugiyama, Norikazu; Iwai, Hidenao; Mizuguchi, Yoshinori; Yamashita, Yutaka

2014-03-01

There is an increasing need for non-invasive imaging techniques in the field of stem cell research. Label-free techniques are the best choice for assessment of stem cells because the cells remain intact after imaging and can be used for further studies such as differentiation induction. To develop a high-resolution label-free imaging system, we have been working on a low-coherence quantitative phase microscope (LC-QPM). LC-QPM is a Linnik-type interference microscope equipped with nanometer-resolution optical-path-length control and capable of obtaining three-dimensional volumetric images. The lateral and vertical resolutions of our system are respectively 0.5 and 0.93 μm and this performance allows capturing sub-cellular morphological features of live cells without labeling. Utilizing LC-QPM, we reported on three-dimensional imaging of membrane fluctuations, dynamics of filopodia, and motions of intracellular organelles. In this presentation, we report three-dimensional morphological imaging of human induced pluripotent stem cells (hiPS cells). Two groups of monolayer hiPS cell cultures were prepared so that one group was cultured in a suitable culture medium that kept the cells undifferentiated, and the other group was cultured in a medium supplemented with retinoic acid, which forces the stem cells to differentiate. The volumetric images of the 2 groups show distinctive differences, especially in surface roughness. We believe that our LC-QPM system will prove useful in assessing many other stem cell conditions.

The Promising Applications of Stem Cells in the Oral Region: Literature Review

PubMed Central

Silva, Luciano Barreto; Neto, Alexandrino Pereira Dos Santos; Pacheco, Rachel Gomes Pelozo; Júnior, Severino Alves; de Menezes, Rebeca Ferraz; Carneiro, Vanda Sanderana Macedo; Araújo, Natália Costa; da Silveira, Marcia Maria Fonseca; de Albuquerque, Diana Santana; Gerbi, Marleny Elizabeth Marquez de Martinez; Álvares, Pamella Recco; de Arruda, José Alcides Almeida; Sobral, Ana Paula Veras

2016-01-01

Introduction: For a long time researchers have tried to find out a way to grow tissues back to the human body in order to solve transplantation problems by offering the unique opportunity to have their organs back, working properly, in search of life dignity. Literature Review: Stem cells seem to be present in many other tissues than researchers had once thought; and in some specific sites they can be easily collected, without the need of expensive interventions. The oral cavity is one of these regions where their collection can be accomplished, with plenty of accessible sites enriched with these precious cells. Aim: The aim of this literature review is to research where in the mouth can scientists find stem cells to be used in the near future. Key-message: The aim of this literature review is to research where stem cells can be found and collected in the oral cavity. PMID:27386008

Potential Role of Induced Pluripotent Stem Cells (IPSCs) for Cell-Based Therapy of the Ocular Surface

PubMed Central

Casaroli-Marano, Ricardo P.; Nieto-Nicolau, Núria; Martínez-Conesa, Eva M.; Edel, Michael; Álvarez-Palomo, Ana B.

2015-01-01

The integrity and normal function of the corneal epithelium are crucial for maintaining the cornea’s transparency and vision. The existence of a cell population with progenitor characteristics in the limbus maintains a dynamic of constant epithelial repair and renewal. Currently, cell-based therapies for bio replacement—cultured limbal epithelial transplantation (CLET) and cultured oral mucosal epithelial transplantation (COMET)—present very encouraging clinical results for treating limbal stem cell deficiency (LSCD) and restoring vision. Another emerging therapeutic approach consists of obtaining and implementing human progenitor cells of different origins in association with tissue engineering methods. The development of cell-based therapies using stem cells, such as human adult mesenchymal or induced pluripotent stem cells (IPSCs), represent a significant breakthrough in the treatment of certain eye diseases, offering a more rational, less invasive, and better physiological treatment option in regenerative medicine for the ocular surface. This review will focus on the main concepts of cell-based therapies for the ocular surface and the future use of IPSCs to treat LSCD. PMID:26239129

Store-Operated Calcium Entries Control Neural Stem Cell Self-Renewal in the Adult Brain Subventricular Zone.

PubMed

Domenichini, Florence; Terrié, Elodie; Arnault, Patricia; Harnois, Thomas; Magaud, Christophe; Bois, Patrick; Constantin, Bruno; Coronas, Valérie

2018-05-01

The subventricular zone (SVZ) is the major stem cell niche in the brain of adult mammals. Within this region, neural stem cells (NSC) proliferate, self-renew and give birth to neurons and glial cells. Previous studies underlined enrichment in calcium signaling-related transcripts in adult NSC. Because of their ability to mobilize sustained calcium influxes in response to a wide range of extracellular factors, store-operated channels (SOC) appear to be, among calcium channels, relevant candidates to induce calcium signaling in NSC whose cellular activities are continuously adapted to physiological signals from the microenvironment. By Reverse Transcription Polymerase Chain Reaction (RT-PCR), Western blotting and immunocytochemistry experiments, we demonstrate that SVZ cells express molecular actors known to build up SOC, namely transient receptor potential canonical 1 (TRPC1) and Orai1, as well as their activator stromal interaction molecule 1 (STIM1). Calcium imaging reveals that SVZ cells display store-operated calcium entries. Pharmacological blockade of SOC with SKF-96365 or YM-58483 (also called BTP2) decreases proliferation, impairs self-renewal by shifting the type of SVZ stem cell division from symmetric proliferative to asymmetric, thereby reducing the stem cell population. Brain section immunostainings show that TRPC1, Orai1, and STIM1 are expressed in vivo, in SOX2-positive SVZ NSC. Injection of SKF-96365 in brain lateral ventricle diminishes SVZ cell proliferation and reduces the ability of SVZ cells to form neurospheres in vitro. The present study combining in vitro and in vivo approaches uncovers a major role for SOC in the control of SVZ NSC population and opens new fields of investigation for stem cell biology in health and disease. Stem Cells 2018;36:761-774. © AlphaMed Press 2018.

Current and future regenerative medicine — Principles, concepts, and therapeutic use of stem cell therapy and tissue engineering in equine medicine

PubMed Central

Koch, Thomas G.; Berg, Lise C.; Betts, Dean H.

2009-01-01

This paper provides a bird’s-eye perspective of the general principles of stem-cell therapy and tissue engineering; it relates comparative knowledge in this area to the current and future status of equine regenerative medicine. The understanding of equine stem cell biology, biofactors, and scaffolds, and their potential therapeutic use in horses are rudimentary at present. Mesenchymal stem cell isolation has been proclaimed from several equine tissues in the past few years. Based on the criteria of the International Society for Cellular Therapy, most of these cells are more correctly referred to as multipotent mesenchymal stromal cells, unless there is proof that they exhibit the fundamental in vivo characteristics of pluripotency and the ability to self-renew. That said, these cells from various tissues hold great promise for therapeutic use in horses. The 3 components of tissue engineering — cells, biological factors, and biomaterials — are increasingly being applied in equine medicine, fuelled by better scaffolds and increased understanding of individual biofactors and cell sources. The effectiveness of stem cell-based therapies and most tissue engineering concepts has not been demonstrated sufficiently in controlled clinical trials in equine patients to be regarded as evidence-based medicine. In the meantime, the medical mantra “do no harm” should prevail, and the application of stem cell-based therapies in the horse should be done critically and cautiously, and treatment outcomes (good and bad) should be recorded and reported. Stem cell and tissue engineering research in the horse has exciting comparative and equine specific perspectives that most likely will benefit the health of horses and humans. Controlled, well-designed studies are needed to move this new equine research field forward. PMID:19412395

Casparian bands occur in the periderm of Pelargonium hortorum stem and root.

PubMed

Meyer, Chris J; Peterson, Carol A

2011-04-01

Casparian bands are characteristic of the endodermis and exodermis of roots, but also occur infrequently in other plant organs, for example stems and leaves. To date, these structures have not been detected in phellem cells of a periderm. The aim of this study was to determine whether Casparian bands occur in phellem cells using tests that are known to detect Casparian bands in cells that also contain suberin lamellae. Both natural periderm and wound-induced structures were examined in shoots and roots. Using Pelargonium hortorum as a candidate species, the following tests were conducted: (1) staining with berberine and counterstaining with aniline blue, (2) mounting sections in concentrated sulphuric acid and (3) investigating the permeability of the walls with berberine as an apoplastic, fluorescent tracer. (1) Berberine-aniline blue staining revealed a modification in the radial and transverse walls of mature phellem cells in both stems and roots. Three days after wounding through to the cortex of stems, the boundary zone cells (pre-existing, living cells nearest the wound) had developed vividly stained primary walls. By 17 d, staining of mature phellem cells of wound-induced periderm was similar to that of natural periderm. (2) Mature native phellem cells of stems resisted acid digestion. (3) Berberine was excluded from the anticlinal (radial and transverse) walls of mature phellem cells in stems and roots, and from the wound-induced boundary zone. Casparian bands are present in mature phellem cells in both stems and roots of P. hortorum. It is proposed that Casparian bands act to retard water loss and pathogen entry through the primary cell walls of the phellem cells, thus contributing to the main functions of the periderm.

Exploiting science? A systematic analysis of complementary and alternative medicine clinic websites' marketing of stem cell therapies.

PubMed

Murdoch, Blake; Zarzeczny, Amy; Caulfield, Timothy

2018-02-28

To identify the frequency and qualitative characteristics of stem cell-related marketing claims made on websites of clinics featuring common types of complementary and alternative medicine practitioners. The involvement of complementary and alternative medicine practitioners in the marketing of stem cell therapies and stem cell-related interventions is understudied. This research explores the extent to which they are involved and collaborate with medical professionals. This knowledge will help with identifying and evaluating potential policy responses to this growing market. Systematic website analysis. Global. US and English-language bias due to methodology. Representations made on clinic websites in relation to practitioner types, stem cell therapies and their targets, stem cell-related interventions. Statements about stem cell therapies relating to evidence of inefficacy, limited evidence of efficacy, general procedural risks, risks specific to the mode of therapy, regulatory status, experimental or unproven nature of therapy. Use of hype language (eg, language that exaggerates potential benefits). 243 websites offered stem cell therapies. Many websites advertised stem cell transplantation from multiple sources, such as adipose-derived (112), bone marrow-derived (100), blood-derived (28), umbilical cord-derived (26) and others. Plant stem cell-based treatments and products (20) were also advertised. Purposes for and targets of treatment included pain, physical injury, a wide range of diseases and illnesses, cosmetic concerns, non-cosmetic ageing, sexual enhancement and others. Medical doctors (130), chiropractors (53) and naturopaths (44) commonly work in the clinics we found to be offering stem cell therapies. Few clinic websites advertising stem cell therapies included important additional information, including statements about evidence of inefficacy (present on only 12.76% of websites), statements about limited evidence of efficacy (18.93%), statements of general risks (24.69%), statements of risks specific to the mode(s) of therapy (5.76%), statements as to the regulatory status of the therapies (30.86%) and statements that the therapy is experimental or unproven (33.33%). Hype language was noted (31.69%). Stem cell therapies and related interventions are marketed for a wide breadth of conditions and are being offered by complementary and alternative practitioners, often in conjunction with medical doctors. Consumer protection and truth-in-advertising regulation could play important roles in addressing misleading marketing practices in this area. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Learn About Stem Cells

MedlinePlus

... Handbook Stem Cell Glossary Search Toggle Nav Stem Cell Basics Stem cells are the foundation from which ... Home > Learn About Stem Cells > Stem Cell Basics Cells in the human body The human body comprises ...

Erythroid differentiation of human induced pluripotent stem cells is independent of donor cell type of origin.

PubMed

Dorn, Isabel; Klich, Katharina; Arauzo-Bravo, Marcos J; Radstaak, Martina; Santourlidis, Simeon; Ghanjati, Foued; Radke, Teja F; Psathaki, Olympia E; Hargus, Gunnar; Kramer, Jan; Einhaus, Martin; Kim, Jeong Beom; Kögler, Gesine; Wernet, Peter; Schöler, Hans R; Schlenke, Peter; Zaehres, Holm

2015-01-01

Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34(+) hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex vivo expansion of induced pluripotent stem cells into erythroid cells, we compared induced pluripotent stem cells from human neural stem cells and human cord blood-derived CD34(+) hematopoietic stem cells and evaluated their potential for differentiation into hematopoietic progenitor and mature red blood cells. Although genome-wide DNA methylation profiling at all promoter regions demonstrates that the epigenetic memory of induced pluripotent stem cells is influenced by the somatic cell type of origin of the stem cells, we found a similar hematopoietic induction potential and erythroid differentiation pattern of induced pluripotent stem cells of different somatic cell origin. All human induced pluripotent stem cell lines showed terminal maturation into normoblasts and enucleated reticulocytes, producing predominantly fetal hemoglobin. Differences were only observed in the growth rate of erythroid cells, which was slightly higher in the induced pluripotent stem cells derived from CD34(+) hematopoietic stem cells. More detailed methylation analysis of the hematopoietic and erythroid promoters identified similar CpG methylation levels in the induced pluripotent stem cell lines derived from CD34(+) cells and those derived from neural stem cells, which confirms their comparable erythroid differentiation potential. Copyright© Ferrata Storti Foundation.

Extensive Determination of Glycan Heterogeneity Reveals an Unusual Abundance of High Mannose Glycans in Enriched Plasma Membranes of Human Embryonic Stem Cells*

PubMed Central

An, Hyun Joo; Gip, Phung; Kim, Jaehan; Wu, Shuai; Park, Kun Wook; McVaugh, Cheryl T.; Schaffer, David V.; Bertozzi, Carolyn R.; Lebrilla, Carlito B.

2012-01-01

Most cell membrane proteins are known or predicted to be glycosylated in eukaryotic organisms, where surface glycans are essential in many biological processes including cell development and differentiation. Nonetheless, the glycosylation on cell membranes remains not well characterized because of the lack of sensitive analytical methods. This study introduces a technique for the rapid profiling and quantitation of N- and O-glycans on cell membranes using membrane enrichment and nanoflow liquid chromatography/mass spectrometry of native structures. Using this new method, the glycome analysis of cell membranes isolated from human embryonic stem cells and somatic cell lines was performed. Human embryonic stem cells were found to have high levels of high mannose glycans, which contrasts with IMR-90 fibroblasts and a human normal breast cell line, where complex glycans are by far the most abundant and high mannose glycans are minor components. O-Glycosylation affects relatively minor components of cell surfaces. To verify the quantitation and localization of glycans on the human embryonic stem cell membranes, flow cytometry and immunocytochemistry were performed. Proteomics analyses were also performed and confirmed enrichment of plasma membrane proteins with some contamination from endoplasmic reticulum and other membranes. These findings suggest that high mannose glycans are the major component of cell surface glycosylation with even terminal glucoses. High mannose glycans are not commonly presented on the surfaces of mammalian cells or in serum yet may play important roles in stem cell biology. The results also mean that distinguishing stem cells from other mammalian cells may be facilitated by the major difference in the glycosylation of the cell membrane. The deep structural analysis enabled by this new method will enable future mechanistic studies on the biological significance of high mannose glycans on stem cell membranes and provide a general tool to examine cell surface glycosylation. PMID:22147732

An Hsp70 peptide initiates NK cell killing of leukemic blasts after stem cell transplantation.

PubMed

Gross, Catharina; Holler, Ernst; Stangl, Stefan; Dickinson, Anne; Pockley, A Graham; Asea, Alexzander A; Mallappa, Nagaraja; Multhoff, Gabriele

2008-04-01

In contrast to solid tumors, leukemic blasts frequently present both Hsp70 and HLA-E on their cell surface and thereby present activating and inhibitory signals to CD94(+) NK cells. In the first 12 months after stem cell transplantation (SCT) CD94(+) NK cells clearly dominate over CD3(+)/CD16(-)/56(-) T and CD3(+)/CD16(+)/56(+) NK-like T cells. An incubation of post-SCT-derived peripheral blood lymphocytes with the Hsp70 peptide TKD and IL-15 enhances the cell surface density of CD56/CD94 and initiates the cytolytic activity of NK cells against Hsp70/HLA-E double-positive autologous and allogeneic leukemic blasts. Hsp70 was identified as the target structure for TKD-activated NK cells.

Naïve Induced Pluripotent Stem Cells Generated From β-Thalassemia Fibroblasts Allow Efficient Gene Correction With CRISPR/Cas9.

PubMed

Yang, Yuanyuan; Zhang, Xiaobai; Yi, Li; Hou, Zhenzhen; Chen, Jiayu; Kou, Xiaochen; Zhao, Yanhong; Wang, Hong; Sun, Xiao-Fang; Jiang, Cizhong; Wang, Yixuan; Gao, Shaorong

2016-01-01

Conventional primed human embryonic stem cells and induced pluripotent stem cells (iPSCs) exhibit molecular and biological characteristics distinct from pluripotent stem cells in the naïve state. Although naïve pluripotent stem cells show much higher levels of self-renewal ability and multidifferentiation capacity, it is unknown whether naïve iPSCs can be generated directly from patient somatic cells and will be superior to primed iPSCs. In the present study, we used an established 5i/L/FA system to directly reprogram fibroblasts of a patient with β-thalassemia into transgene-free naïve iPSCs with molecular signatures of ground-state pluripotency. Furthermore, these naïve iPSCs can efficiently produce cross-species chimeras. Importantly, using the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 nuclease genome editing system, these naïve iPSCs exhibit significantly improved gene-correction efficiencies compared with the corresponding primed iPSCs. Furthermore, human naïve iPSCs could be directly generated from noninvasively collected urinary cells, which are easily acquired and thus represent an excellent cell resource for further clinical trials. Therefore, our findings demonstrate the feasibility and superiority of using patient-specific iPSCs in the naïve state for disease modeling, gene editing, and future clinical therapy. In the present study, transgene-free naïve induced pluripotent stem cells (iPSCs) directly converted from the fibroblasts of a patient with β-thalassemia in a defined culture system were generated. These naïve iPSCs, which show ground-state pluripotency, exhibited significantly improved single-cell cloning ability, recovery capacity, and gene-targeting efficiency compared with conventional primed iPSCs. These results provide an improved strategy for personalized treatment of genetic diseases such as β-thalassemia. ©AlphaMed Press.

Naïve Induced Pluripotent Stem Cells Generated From β-Thalassemia Fibroblasts Allow Efficient Gene Correction With CRISPR/Cas9

PubMed Central

Yang, Yuanyuan; Zhang, Xiaobai; Yi, Li; Hou, Zhenzhen; Chen, Jiayu; Kou, Xiaochen; Zhao, Yanhong; Wang, Hong; Sun, Xiao-Fang; Jiang, Cizhong

2016-01-01

Conventional primed human embryonic stem cells and induced pluripotent stem cells (iPSCs) exhibit molecular and biological characteristics distinct from pluripotent stem cells in the naïve state. Although naïve pluripotent stem cells show much higher levels of self-renewal ability and multidifferentiation capacity, it is unknown whether naïve iPSCs can be generated directly from patient somatic cells and will be superior to primed iPSCs. In the present study, we used an established 5i/L/FA system to directly reprogram fibroblasts of a patient with β-thalassemia into transgene-free naïve iPSCs with molecular signatures of ground-state pluripotency. Furthermore, these naïve iPSCs can efficiently produce cross-species chimeras. Importantly, using the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 nuclease genome editing system, these naïve iPSCs exhibit significantly improved gene-correction efficiencies compared with the corresponding primed iPSCs. Furthermore, human naïve iPSCs could be directly generated from noninvasively collected urinary cells, which are easily acquired and thus represent an excellent cell resource for further clinical trials. Therefore, our findings demonstrate the feasibility and superiority of using patient-specific iPSCs in the naïve state for disease modeling, gene editing, and future clinical therapy. Significance In the present study, transgene-free naïve induced pluripotent stem cells (iPSCs) directly converted from the fibroblasts of a patient with β-thalassemia in a defined culture system were generated. These naïve iPSCs, which show ground-state pluripotency, exhibited significantly improved single-cell cloning ability, recovery capacity, and gene-targeting efficiency compared with conventional primed iPSCs. These results provide an improved strategy for personalized treatment of genetic diseases such as β-thalassemia. PMID:26676643

[Progress in stem cells and regenerative medicine].

PubMed

Wang, Libin; Zhu, He; Hao, Jie; Zhou, Qi

2015-06-01

Stem cells have the ability to differentiate into all types of cells in the body and therefore have great application potential in regenerative medicine, in vitro disease modelling and drug screening. In recent years, stem cell technology has made great progress, and induced pluripotent stem cell technology revolutionizes the whole stem cell field. At the same time, stem cell research in our country has also achieved great progress and becomes an indispensable power in the worldwide stem cell research field. This review mainly focuses on the research progress in stem cells and regenerative medicine in our country since the advent of induced pluripotent stem cell technology, including induced pluripotent stem cells, transdifferentiation, haploid stem cells, and new gene editing tools.

Application of Graphene Based Nanotechnology in Stem Cells Research.

PubMed

Hu, Shanshan; Zeng, Yongxiang; Yang, Shuying; Qin, Han; Cai, He; Wang, Jian

2015-09-01

The past several years have witnessed significant advances in stem cell therapy, tissue engineering and regenerative medicine. Graphene, with its unique properties such as high electrical conductivity, elasticity and good molecule absorption, have potential for creating the next generation of biomaterials. This review summarizes the interrelationship between graphene and stem cells. The analysis of graphene when applied on mesenchymal stem cells, neural stem cells, induced pluripotent stem cells, embryonic stem cells, periodontal ligament stem cells, human adipose-derived stem cells and cancer stem cells, and how graphene influences cell behavior and differentiation are discussed in details.

Isolation and characterisation of human gingival margin-derived STRO-1/MACS+ and MACS− cell populations

PubMed Central

El-Sayed, Karim M Fawzy; Paris, Sebastian; Graetz, Christian; Kassem, Neemat; Mekhemar, Mohamed; Ungefroren, Hendrick; Fändrich, Fred; Dörfer, Christof

2015-01-01

Recently, gingival margin-derived stem/progenitor cells isolated via STRO-1/magnetic activated cell sorting (MACS) showed remarkable periodontal regenerative potential in vivo. As a second-stage investigation, the present study's aim was to perform in vitro characterisation and comparison of the stem/progenitor cell characteristics of sorted STRO-1-positive (MACS+) and STRO-1-negative (MACS−) cell populations from the human free gingival margin. Cells were isolated from the free gingiva using a minimally invasive technique and were magnetically sorted using anti-STRO-1 antibodies. Subsequently, the MACS+ and MACS− cell fractions were characterized by flow cytometry for expression of CD14, CD34, CD45, CD73, CD90, CD105, CD146/MUC18 and STRO-1. Colony-forming unit (CFU) and multilineage differentiation potential were assayed for both cell fractions. Mineralisation marker expression was examined using real-time polymerase chain reaction (PCR). MACS+ and MACS− cell fractions showed plastic adherence. MACS+ cells, in contrast to MACS− cells, showed all of the predefined mesenchymal stem/progenitor cell characteristics and a significantly higher number of CFUs (P<0.01). More than 95% of MACS+ cells expressed CD105, CD90 and CD73; lacked the haematopoietic markers CD45, CD34 and CD14, and expressed STRO-1 and CD146/MUC18. MACS− cells showed a different surface marker expression profile, with almost no expression of CD14 or STRO-1, and more than 95% of these cells expressed CD73, CD90 and CD146/MUC18, as well as the haematopoietic markers CD34 and CD45 and CD105. MACS+ cells could be differentiated along osteoblastic, adipocytic and chondroblastic lineages. In contrast, MACS− cells demonstrated slight osteogenic potential. Unstimulated MACS+ cells showed significantly higher expression of collagen I (P<0.05) and collagen III (P<0.01), whereas MACS− cells demonstrated higher expression of osteonectin (P<0.05; Mann–Whitney). The present study is the first to compare gingival MACS+ and MACS− cell populations demonstrating that MACS+ cells, in contrast to MACS− cells, harbour stem/progenitor cell characteristics. This study also validates the effectiveness of the STRO-1/MACS+ technique for the isolation of gingival stem/progenitor cells. Human free gingival margin-derived STRO-1/MACS+ cells are a unique renewable source of multipotent stem/progenitor cells. PMID:25257881

Gelatin methacrylamide hydrogel with graphene nanoplatelets for neural cell-laden 3D bioprinting.

PubMed

Wei Zhu; Harris, Brent T; Zhang, Lijie Grace

2016-08-01

Nervous system is extremely complex which leads to rare regrowth of nerves once injury or disease occurs. Advanced 3D bioprinting strategy, which could simultaneously deposit biocompatible materials, cells and supporting components in a layer-by-layer manner, may be a promising solution to address neural damages. Here we presented a printable nano-bioink composed of gelatin methacrylamide (GelMA), neural stem cells, and bioactive graphene nanoplatelets to target nerve tissue regeneration in the assist of stereolithography based 3D bioprinting technique. We found the resultant GelMA hydrogel has a higher compressive modulus with an increase of GelMA concentration. The porous GelMA hydrogel can provide a biocompatible microenvironment for the survival and growth of neural stem cells. The cells encapsulated in the hydrogel presented good cell viability at the low GelMA concentration. Printed neural construct exhibited well-defined architecture and homogenous cell distribution. In addition, neural stem cells showed neuron differentiation and neurites elongation within the printed construct after two weeks of culture. These findings indicate the 3D bioprinted neural construct has great potential for neural tissue regeneration.

A revisionist history of adult marrow stem cell biology or 'they forgot about the discard'.

PubMed

Quesenberry, P; Goldberg, L

2017-08-01

The adult marrow hematopoietic stem cell biology has largely been based on studies of highly purified stem cells. This is unfortunate because during the stem cell purification the great bulk of stem cells are discarded. These cells are actively proliferating. The final purified stem cell is dormant and not representative of the whole stem cell compartment. Thus, a large number of studies on the cellular characteristics, regulators and molecular details of stem cells have been carried on out of non-represented cells. Niche studies have largely pursued using these purified stem cells and these are largely un-interpretable. Other considerations include the distinction between baseline and transplant stem cells and the modulation of stem cell phenotype by extracellular vesicles, to cite a non-inclusive list. Work needs to proceed on characterizing the true stem cell population.

Effectiveness of Partner Social Support Predicts Enduring Psychological Distress after Hematopoietic Stem Cell Transplantation

ERIC Educational Resources Information Center

Rini, Christine; Redd, William H.; Austin, Jane; Mosher, Catherine E.; Meschian, Yeraz Markarian; Isola, Luis; Scigliano, Eileen; Moskowitz, Craig H.; Papadopoulos, Esperanza; Labay, Larissa E.; Rowley, Scott; Burkhalter, Jack E.; Schetter, Christine Dunkel; DuHamel, Katherine N.

2011-01-01

Objective: Hematopoietic stem cell transplant (HSCT) survivors who are 1 to 3 years posttransplant are challenged by the need to resume valued social roles and activities--a task that may be complicated by enduring transplant-related psychological distress common in this patient population. The present study investigated whether transplant…

Ovarian cancer stem-like cells with induced translineage-differentiation capacity and are suppressed by alkaline phosphatase inhibitor

PubMed Central

Liu, Kuei-Chun; Yo, Yi-Te; Huang, Rui-Lan; Wang, Yu-Chi; Liao, Yu-Ping; Huang, Tien-Shuo; Chao, Tai-Kuang; Lin, Chi-Kang; Weng, Shao-Ju; Ma, Kuo-Hsing; Chang, Cheng-Chang; Yu, Mu-Hsien; Lai, Hung-Cheng

2013-01-01

Spheroid formation is one property of stem cells—such as embryo-derived or neural stem cells—that has been used for the enrichment of cancer stem-like cells (CSLCs). However, it is unclear whether CSLC-derived spheroids are heterogeneous or whether they share common embryonic stemness properties. Understanding these features might lead to novel therapeutic approaches. Ovarian carcinoma is a deadly disease of women. We identified two types of spheroids (SR1 and SR2) from ovarian cancer cell lines and patients' specimens according to their morphology. Both types expressed stemness markers and could self-renew and initiate tumors when a low number of cells were used. Only SR1 could differentiate into multiple-lineage cell types under specific induction conditions. SR1 spheroids could differentiate to SR2 spheroids through epithelial–mesenchymal transition. Alkaline phosphatase (ALP) was highly expressed in SR1 spheroids, decreased in SR2 spheroids, and was absent in differentiated progenies in accordance with the loss of stemness properties. We verified that ALP can be a marker for ovarian CSLCs, and patients with greater ALP expression is related to advanced clinical stages and have a higher risk of recurrence and lower survival rate. The ALP inhibitor, levamisole, disrupted the self-renewal of ovarian CSLCs in vitro and tumor growth in vivo. In summary, this research provides a plastic ovarian cancer stem cell model and a new understanding of the cross-link between stem cells and cancers. This results show that ovarian CSLCs can be suppressed by levamisole. Our findings demonstrated that some ovarian CSLCs may restore ALP activity, and this suggests that inhibition of ALP activity may present a new opportunity for treatment of ovarian cancer. PMID:24280306

Enhancement of organ regeneration in animal models by a stem cell-stimulating plant mixture.

PubMed

Kiss, István; Tibold, Antal; Halmosi, Róbert; Bartha, Eva; Koltai, Katalin; Orsós, Zsuzsanna; Bujdosó, László; Ember, István

2010-06-01

Adult stem cells play an important role in the regeneration of damaged organs. Attempts have already been made to enhance stem cell production by cytokines, in order to increase the improvement of cardiac functions after myocardial infarction. In our present study we investigated the possibility whether instead of cytokine injection dietary stimulation of stem cell production accelerates the organ regeneration in animals. A dietary supplement, Olimpiq StemXCell (Crystal Institute Ltd., Eger, Hungary), containing plant extracts (previously proved to increase the number of circulating CD34(+) cells) was consumed in human equivalent doses by the experimental animals. In the first experiment carbon tetrachloride was applied to CBA/Ca mice, to induce liver damage, and liver weights between StemXCell-fed and control animals were compared 10 days after the treatment. In the second model experimental diabetes was induced in F344 rats by alloxan. Blood sugar levels were measured for 5 weeks in the control and StemXCell-fed groups. The third part of the study investigated the effect of StemXCell on cardiac functions. Eight weeks after causing a myocardial infarction in Wistar rats by isoproterenol, left ventricular ejection fraction was determined as a functional parameter of myocardial regeneration. In all three animal models StemXCell consumption statistically significantly improved the organ regeneration (relative liver weights, 4.78 +/-0.06 g/100 g vs. 4.97 +/- 0.07 g/100 g; blood sugar levels at week 5, 16 +/- 1.30 mmol/L vs. 10.2 +/- 0.92 mmol/L; ejection fraction, 57.5 +/- 2.23 vs. 68.2 +/- 4.94; controls vs. treated animals, respectively). Our study confirms the hypothesis that dietary enhancement of stem cell production may protect against organ injuries and helps in the regeneration.

[German stem-cell law: content and critique].

PubMed

Simon, Jürgen

2002-01-01

The author analyzes in this work the new German Stem Cells Act, approved by the German Parliament on 10 of May 2002. In this law it is prohibited with general character the investigation with stem cells of embryonic origin, although it is allowed under certain very strict requirements. The conflict that arises among a very strict protection of the embryo, such and like it happens in the present law, and the constitutional right to scientific investigation is also analyzed, a reference to the derivative problems of the lack of clarity of some articles of the law is also made.

Exosomes derived from human mesenchymal stem cells promote gastric cancer cell growth and migration via the activation of the Akt pathway.

PubMed

Gu, Hongbing; Ji, Runbi; Zhang, Xu; Wang, Mei; Zhu, Wei; Qian, Hui; Chen, Yongchang; Jiang, Pengcheng; Xu, Wenrong

2016-10-01

Mesenchymal stem cells (MSCs) are a component of the tumor microenvironment and can promote the development of gastric cancer through paracrine mechanism. However, the effects of MSC‑exosomes (MSC‑ex) on gastric cancer are less clear. The present study reported that MSC‑ex promoted the proliferative and metastatic potential of gastric cancer cells ex vivo. It was found that MSC‑ex enhanced the migration and invasion of HGC‑27 cells via the induction of the epithelial‑mesenchymal transition. MSC‑ex increased the expression of mesenchymal markers and reduced the expression of epithelial markers in gastric cancer cells. MSC‑ex also enhanced the tumorigenicity of gastric cancer cells ex vivo. MSC‑ex induced the stemness of gastric cancer cells. The expression of octamer‑binding transcription factor 4, ex determining region Y‑box 2 and Lin28B significantly increased in gastric cancer cells treated with MSC‑ex. The present study further demonstrated that MSC‑ex elicited these biological effects predominantly via the activation of the protein kinase B signaling pathway. Taken together, the present findings provided novel evidence for the role of MSC‑ex in gastric cancer and a new opportunity for improving the efficiency of gastric cancer treatment by targeting MSC‑ex.

Effect of nanodiamond modification of siloxane surfaces on stem cell behaviour

NASA Astrophysics Data System (ADS)

Keremidarska, M.; Hikov, T.; Radeva, E.; Pramatarova, L.; Krasteva, N.

2014-12-01

Mesenchymal stem cells (MSCs) hold a great promise for use in many cell therapies and tissue engineering due to their remarkable potential to replicate indefinitely and differentiate into various cell types. Many efforts have been put to study the factors controlling stem cell differentiation. However, still little knowledge has been gained to what extent biomaterials properties influence stem cell adhesion, growth and differentiation. Research utilizing bone marrow-derived MSCs has concentrated on development of specific materials which can enhance specific differentiation of stem cells e.g. osteogenic and chondrogenic. In the present work we have modified an organosilane, hexamethyldisiloxane (HMDS) with detonation nanodiamond (DND) particles aiming to improve adhesion, growth and osteodifferentiation of rat mesenchymal stem cells. HMDS/DND films were deposited on cover glass using two approaches: premixing of both compounds, followed by plasma polymerization (PP) and PP of HMDS followed by plasma deposition of DND particles. We did not observe however an increase in rMSCs adhesion and growth on DND-modified PPHMDS surfaces compared to unmodified PPHMDS. When we studied alkaline phosphatase (ALP) activity, which is a major sign for early osteodifferentiation, we found the highest ALP activity on the PPHMDS/DND material, prepared by consequent deposition while on the other composite material ALP activity was the lowest. These results suggested that DND-modified materials were able to control osteodifferention in MSCs depending on the deposition approach. Modification of HMDS with DND particles by consequent plasma deposition seems to be a promising approach to produce biomaterials capable to guide stem cell differentiation toward osteoblasts and thus to be used in bone tissue engineering.

Physiologic oxygen concentration enhances the stem-like properties of CD133+ human glioblastoma cells in vitro.

PubMed

McCord, Amy M; Jamal, Muhammad; Shankavaram, Uma T; Shankavarum, Uma T; Lang, Frederick F; Camphausen, Kevin; Tofilon, Philip J

2009-04-01

In vitro investigations of tumor stem-like cells (TSC) isolated from human glioblastoma (GB) surgical specimens have been done primarily at an atmospheric oxygen level of 20%. To determine whether an oxygen level more consistent with in situ conditions affects their stem cell-like characteristics, we compared GB TSCs grown under conditions of 20% and 7% oxygen. Growing CD133(+) cells sorted from three GB neurosphere cultures at 7% O(2) reduced their doubling time and increased the self-renewal potential as reflected by clonogenicity. Furthermore, at 7% oxygen, the cultures exhibited an enhanced capacity to differentiate along both the glial and neuronal pathways. As compared with 20%, growth at 7% oxygen resulted in an increase in the expression levels of the neural stem cell markers CD133 and nestin as well as the stem cell markers Oct4 and Sox2. In addition, whereas hypoxia inducible factor 1alpha was not affected in CD133(+) TSCs grown at 7% O(2), hypoxia-inducible factor 2alpha was expressed at higher levels as compared with 20% oxygen. Gene expression profiles generated by microarray analysis revealed that reducing oxygen level to 7% resulted in the up-regulation and down-regulation of a significant number of genes, with more than 140 being commonly affected among the three CD133(+) cultures. Furthermore, Gene Ontology categories up-regulated at 7% oxygen included those associated with stem cells or GB TSCs. Thus, the data presented indicate that growth at the more physiologically relevant oxygen level of 7% enhances the stem cell-like phenotype of CD133(+) GB cells.

Stem Cells

MedlinePlus

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

Agent-Based Deterministic Modeling of the Bone Marrow Homeostasis.

PubMed

Kurhekar, Manish; Deshpande, Umesh

2016-01-01

Modeling of stem cells not only describes but also predicts how a stem cell's environment can control its fate. The first stem cell populations discovered were hematopoietic stem cells (HSCs). In this paper, we present a deterministic model of bone marrow (that hosts HSCs) that is consistent with several of the qualitative biological observations. This model incorporates stem cell death (apoptosis) after a certain number of cell divisions and also demonstrates that a single HSC can potentially populate the entire bone marrow. It also demonstrates that there is a production of sufficient number of differentiated cells (RBCs, WBCs, etc.). We prove that our model of bone marrow is biologically consistent and it overcomes the biological feasibility limitations of previously reported models. The major contribution of our model is the flexibility it allows in choosing model parameters which permits several different simulations to be carried out in silico without affecting the homeostatic properties of the model. We have also performed agent-based simulation of the model of bone marrow system proposed in this paper. We have also included parameter details and the results obtained from the simulation. The program of the agent-based simulation of the proposed model is made available on a publicly accessible website.

Morphological description of limbal epithelium: searching for stem cells crypts in the dog, cat, pig, cow, sheep and horse.

PubMed

Patruno, M; Perazzi, A; Martinello, T; Blaseotto, A; Di Iorio, E; Iacopetti, I

2017-06-01

The cornea provides protection and transparency to the eye, allowing an optimal sharpness view. In some pathological conditions the cornea is able to regenerate thanks to the presence of a stem cells reservoir present at the level of the transition area between cornea and sclera (limbus). Corneal cell therapies in Veterinary Medicine are really limited due to the lacking of knowledge about the anatomy of the limbal area, the putative presence of stem cells and their identification in domestic species. The aim of this study was to provide an overview of the main distinctive structural features of the sclero-corneal junction and conjunctival-corneal junction areas in some species of veterinary importance, using optic microscope observations of histological sections. The resulting data were compared with cornea from humans adapting protocols already used to identify stem cells by means of a specific cellular marker. We tested the expression of ΔNp63α isoform in the cornea basal cells, trying to correlate the distribution profile with areas of highly proliferative turnover. The results obtained from this study represent a first step towards the identification of a corneal stem cells reservoir in different animals.

Developing Induced Pluripotent Stem Cell-Based Therapy for the Masses.

PubMed

Rao, Mahendra S; Atala, Anthony

2016-02-01

The discovery of induced pluripotent stem cells and the ability to manufacture them using clinically compliant protocols has the potential to revolutionize the field of regenerative medicine. However, realizing this potential requires the development of processes that are reliable, reproducible, and cost-effective and that at the same time do not compromise the safety of the individuals receiving this therapy. In the present report, we discuss how cost reductions can be obtained using our experience with obtaining approval of biologic agents, autologous therapy, and the recent approval of cord blood banks. Significance: For therapy to be widely available, the cost of manufacturing stem cells must be reduced. The steps proposed in the present report, when implemented, have the potential to reduce these costs significantly. ©AlphaMed Press.

Potential use of mesenchymal stem cells in human meniscal repair: current insights

PubMed Central

Pak, Jaewoo; Lee, Jung Hun; Park, Kwang Seung; Jeon, Jeong Ho; Lee, Sang Hee

2017-01-01

The menisci of the human knee play an important role in maintaining normal functions to provide stability and nutrition to the articular cartilage, and to absorb shock. Once injured, these important structures have very limited natural healing potential. Unfortunately, the traditional arthroscopic meniscectomy performed on these damaged menisci may predispose the joint toward early development of osteoarthritis. Although a very limited number of studies are available, mesenchymal stem cells (MSCs) have been investigated as an alternative therapeutic modality to repair human knee meniscal tears. This review summarizes the results of published applications of MSCs in human patients, which showed that the patients who received MSCs (autologous adipose tissue-derived stem cells or culture-expanded bone marrow-derived stem cells) presented symptomatic improvements, along with magnetic resonance imaging evidences of the meniscal repair. PMID:28356779

Targeting PTPRK-RSPO3 colon tumours promotes differentiation and loss of stem-cell function.

PubMed

Storm, Elaine E; Durinck, Steffen; de Sousa e Melo, Felipe; Tremayne, Jarrod; Kljavin, Noelyn; Tan, Christine; Ye, Xiaofen; Chiu, Cecilia; Pham, Thinh; Hongo, Jo-Anne; Bainbridge, Travis; Firestein, Ron; Blackwood, Elizabeth; Metcalfe, Ciara; Stawiski, Eric W; Yauch, Robert L; Wu, Yan; de Sauvage, Frederic J

2016-01-07

Colorectal cancer remains a major unmet medical need, prompting large-scale genomics efforts in the field to identify molecular drivers for which targeted therapies might be developed. We previously reported the identification of recurrent translocations in R-spondin genes present in a subset of colorectal tumours. Here we show that targeting RSPO3 in PTPRK-RSPO3-fusion-positive human tumour xenografts inhibits tumour growth and promotes differentiation. Notably, genes expressed in the stem-cell compartment of the intestine were among those most sensitive to anti-RSPO3 treatment. This observation, combined with functional assays, suggests that a stem-cell compartment drives PTPRK-RSPO3 colorectal tumour growth and indicates that the therapeutic targeting of stem-cell properties within tumours may be a clinically relevant approach for the treatment of colorectal tumours.

Downregulation of mitochondrial cyclooxygenase-2 inhibits the stemness of nasopharyngeal carcinoma by decreasing the activity of dynamin-related protein 1

PubMed Central

Zhou, Teng-Jian; Zhang, Shi-Li; He, Cheng-Yong; Zhuang, Qun-Ying; Han, Pei-Yu; Jiang, Sheng-Wei; Yao, Huan; Huang, Yi-Jun; Ling, Wen-Hua; Lin, Yu-Chun; Lin, Zhong-Ning

2017-01-01

Cancer stem cells (CSCs) are a small subset of malignant cells, possessing stemness, with strong tumorigenic capability, conferring resistance to therapy and leading to the relapse of nasopharyngeal carcinoma (NPC). Our previous study suggested that cyclooxygenase-2 (COX-2) would be a novel target for the CSCs-like side population (SP) cells in NPC. In the present study, we further found that COX-2 maintained the stemness of NPC by enhancing the activity of mitochondrial dynamin-related protein 1 (Drp1), a mitochondrial fission mediator, by studying both sorted SP cells from NPC cell lines and gene expression analyses in NPC tissues. Using both overexpression and knockdown of COX-2, we demonstrated that the localization of COX-2 at mitochondria promotes the stemness of NPC by recruiting the mitochondrial translocation of p53, increasing the activity of Drp1 and inducing mitochondrial fisson. Inhibition of the expression or the activity of Drp1 by siRNA or Mdivi-1 downregulates the stemness of NPC. The present study also found that inhibition of mitochondrial COX-2 with resveratrol (RSV), a natural phytochemical, increased the sensitivity of NPC to 5-fluorouracil (5-FU), a classical chemotherapy drug for NPC. The underlying mechanism is that RSV suppresses mitochondrial COX-2, thereby reducing NPC stemness by inhibiting Drp1 activity as demonstrated in both the in vitro and the in vivo studies. Taken together, the results of this study suggest that mitochondrial COX-2 is a potential theranostic target for the CSCs in NPC. Inhibition of mitochondrial COX-2 could be an attractive therapeutic option for the effective clinical treatment of therapy-resistant NPC. PMID:28435473

The Role of Integrin α6 (CD49f) in Stem Cells: More than a Conserved Biomarker.

PubMed

Krebsbach, Paul H; Villa-Diaz, Luis G

2017-08-01

Stem cells have the capacity for self-renewal and differentiation into specialized cells that form and repopulated all tissues and organs, from conception to adult life. Depending on their capacity for differentiation, stem cells are classified as totipotent (ie, zygote), pluripotent (ie, embryonic stem cells), multipotent (ie, neuronal stem cells, hematopoietic stem cells, epithelial stem cells, etc.), and unipotent (ie, spermatogonial stem cells). Adult or tissue-specific stem cells reside in specific niches located in, or nearby, their organ or tissue of origin. There, they have microenvironmental support to remain quiescent, to proliferate as undifferentiated cells (self-renewal), and to differentiate into progenitors or terminally differentiated cells that migrate from the niche to perform specialized functions. The presence of proteins at the cell surface is often used to identify, classify, and isolate stem cells. Among the diverse groups of cell surface proteins used for these purposes, integrin α6, also known as CD49f, may be the only biomarker commonly found in more than 30 different populations of stem cells, including some cancer stem cells. This broad expression among stem cell populations indicates that integrin α6 may play an important and conserved role in stem cell biology, which is reaffirmed by recent demonstrations of its role maintaining self-renewal of pluripotent stem cells and breast and glioblastoma cancer stem cells. Therefore, this review intends to highlight and synthesize new findings on the importance of integrin α6 in stem cell biology.

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

PubMed

Peña, Ike dela; Borlongan, Cesar V

2015-12-01

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

Endocrine disrupting chemicals affect the adipogenic differentiation of mesenchymal stem cells in distinct ontogenetic windows

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

Biemann, Ronald, E-mail: ronald.biemann@medizin.uni-halle.de; Navarrete Santos, Anne; Navarrete Santos, Alexander

Highlights: Black-Right-Pointing-Pointer Endocrine disrupting chemicals affect adipogenesis in mesenchymal stem cells (MSC). Black-Right-Pointing-Pointer The adipogenic impact depends strongly on the window of exposure. Black-Right-Pointing-Pointer Bisphenol A reduces the potential of MSC to differentiate into adipocytes. Black-Right-Pointing-Pointer DEHP and TBT trigger the adipogenic differentiation of mesenchymal stem cells. Black-Right-Pointing-Pointer BPA, DEHP and TBT did not affect adipogenesis in embryonic stem cells. -- Abstract: Endocrine disrupting chemicals (EDC) like bisphenol A (BPA), bis(2-ethylhexyl)phthalate (DEHP) and tributyltin (TBT) are ubiquitously present in the environment and in human tissues. They bind to nuclear hormone receptors and affect cellular and developmental processes. In this study,more » we show that BPA, DEHP and TBT affect the adipogenic differentiation of murine mesenchymal stem cells (MSC, C3H/10T1/2) in a concentration-, stage- and compound-specific manner. C3H/10T1/2 cells and embryonic stem cells (CGR8) were exposed to BPA, DEHP or TBT at different stages of cell determination and differentiation (undifferentiated growth, adipogenic induction and terminal adipogenic differentiation). The final amount of differentiated adipocytes, cellular triglyceride content and mRNA expression of adipogenic marker genes (adiponectin, FABP4, PPAR{gamma}2, LPL) were quantified and compared with corresponding unexposed cells. BPA (10 {mu}M) decreased subsequent adipogenic differentiation of MSC, when cells were exposed during undifferentiated growth. In contrast, DEHP (100 {mu}M) during the hormonal induction period, and TBT (100 nM) in all investigated stages, enhanced adipogenesis. Importantly, exposure of undifferentiated murine embryonic stem cells did not show any effect of the investigated EDC on subsequent adipogenic differentiation.« less

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

PubMed

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

2018-03-01

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

Alkaline phosphatase and OCT-3/4 as useful markers for predicting susceptibility of human deciduous teeth-derived dental pulp cells to reprogramming factor-induced iPS cells.

PubMed

Inada, Emi; Saitoh, Issei; Kubota, Naoko; Soda, Miki; Matsueda, Kazunari; Murakami, Tomoya; Sawami, Tadashi; Kagoshima, Akiko; Yamasaki, Youichi; Sato, Masahiro

2017-11-01

The aim of the present study was to prove that primary cells enriched with stem cells are more easily reprogrammed to generate induced pluripotent stem (iPS) cells than those with scarce numbers of stem cells. We surveyed the alkaline phosphatase (ALP) activity in five primarily-isolated human deciduous teeth-derived dental pulp cells (HDDPC) with cytochemical staining to examine the possible presence of stem cells. Next, the expression of stemness-specific factors, such as OCT(Octumer-binding transcription factor)3/4, NANOG, SOX2(SRY (sex determining region Y)-box 2), CD90, muscle segment homeodomain homeobox (MSX) 1, and MSX2, was assessed with a reverse transcription polymerase chain reaction method. Finally, these isolated HDDPC were transfected with plasmids carrying genes coding Yamanaka factors to determine whether these cells could be reprogrammed to generate iPS cells. Of the five primarily-isolated HDDPC, two (HDDPC-1 and -5) exhibited higher degrees of ALP activity. OCT-3/4 expression was also prominent in those two lines. Furthermore, these two lines proliferated faster than the other three lines. The transfection of HDDPC with Yamanaka factors resulted in the generation of iPS cells from HDDPC-1 and -5. The number of cells with the stemness property of HDDPC differs among individuals, which suggests that HDDPC showing an increased expression of both ALP and OCT-3/4 can be more easily reprogrammed to generate iPS cells after the forced expression of reprogramming factors. © 2016 John Wiley & Sons Australia, Ltd.

Are nestin-positive mesenchymal stromal cells a better source of cells for CNS repair?

PubMed

Lindsay, Susan L; Barnett, Susan C

2017-06-01

In recent years there has been a great deal of research within the stem cell field which has led to the definition and classification of a range of stem cells from a plethora of tissues and organs. Stem cells, by classification, are considered to be pluri- or multipotent and have both self-renewal and multi-differentiation capabilities. Presently there is a great deal of interest in stem cells isolated from both embryonic and adult tissues in the hope they hold the therapeutic key to restoring or treating damaged cells in a number of central nervous system (CNS) disorders. In this review we will discuss the role of mesenchymal stromal cells (MSCs) isolated from human olfactory mucosa, with particular emphasis on their potential role as a candidate for transplant mediated repair in the CNS. Since nestin expression defines the entire population of olfactory mucosal derived MSCs, we will compare these cells to a population of neural crest derived nestin positive population of bone marrow-MSCs. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

TOOTH (The Open study Of dental pulp stem cell Therapy in Humans): Study protocol for evaluating safety and feasibility of autologous human adult dental pulp stem cell therapy in patients with chronic disability after stroke.

PubMed

Nagpal, Anjali; Kremer, Karlea L; Hamilton-Bruce, Monica A; Kaidonis, Xenia; Milton, Austin G; Levi, Christopher; Shi, Songtao; Carey, Leeanne; Hillier, Susan; Rose, Miranda; Zacest, Andrew; Takhar, Parabjit; Koblar, Simon A

2016-07-01

Stroke represents a significant global disease burden. As of 2015, there is no chemical or biological therapy proven to actively enhance neurological recovery during the chronic phase post-stroke. Globally, cell-based therapy in stroke is at the stage of clinical translation and may improve neurological function through various mechanisms such as neural replacement, neuroprotection, angiogenesis, immuno-modulation, and neuroplasticity. Preclinical evidence in a rodent model of middle cerebral artery ischemic stroke as reported in four independent studies indicates improvement in neurobehavioral function with adult human dental pulp stem cell therapy. Human adult dental pulp stem cells present an exciting potential therapeutic option for improving post-stroke disability. TOOTH (The Open study Of dental pulp stem cell Therapy in Humans) will investigate the use of autologous stem cell therapy for stroke survivors with chronic disability, with the following objectives: (a) determine the maximum tolerable dose of autologous dental pulp stem cell therapy; (b) define that dental pulp stem cell therapy at the maximum tolerable dose is safe and feasible in chronic stroke; and (c) estimate the parameters of efficacy required to design a future Phase 2/3 clinical trial. TOOTH is a Phase 1, open-label, single-blinded clinical trial with a pragmatic design that comprises three stages: Stage 1 will involve the selection of 27 participants with middle cerebral artery ischemic stroke and the commencement of autologous dental pulp stem cell isolation, growth, and testing in sequential cohorts (n = 3). Stage 2 will involve the transplantation of dental pulp stem cell in each cohort of participants with an ascending dose and subsequent observation for a 6-month period for any dental pulp stem cell-related adverse events. Stage 3 will investigate the neurosurgical intervention of the maximum tolerable dose of autologous dental pulp stem cell followed by 9 weeks of intensive task-specific rehabilitation. Advanced magnetic resonance and positron emission tomography neuro-imaging, and clinical assessment will be employed to probe any change afforded by stem cell therapy in combination with rehabilitation. Nine participants will step-wise progress in Stage 2 to a dose of up to 10 million dental pulp stem cell, employing a cumulative 3 + 3 statistical design with low starting stem cell dose and subsequent dose escalation, assuming that an acceptable probability of dose-limiting complications is between 1 in 6 (17%) and 1 in 3 (33%) of patients. In Stage 3, another 18 participants will receive an intracranial injection with the maximum tolerable dose of dental pulp stem cell. The primary outcomes to be measured are safety and feasibility of intracranial administration of autologous human adult DPSC in patients with chronic stroke and determination of the maximum tolerable dose in human subjects. Secondary outcomes include estimation of the measures of effectiveness required to design a future Phase 2/3 clinical trial. © 2016 World Stroke Organization.

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 by the LESC hypothesis. PMID:25815115

The early expansion of anergic NKG2Apos/CD56dim/CD16neg natural killer cells represents a therapeutic target in haploidentical haematopoietic stem cell transplantation.

PubMed

Roberto, Alessandra; Di Vito, Clara; Zaghi, Elisa; Mazza, Emilia Maria Cristina; Capucetti, Arianna; Calvi, Michela; Tentorio, Paolo; Zanon, Veronica; Sarina, Barbara; Mariotti, Jacopo; Bramanti, Stefania; Tenedini, Elena; Tagliafico, Enrico; Bicciato, Silvio; Santoro, Armando; Roederer, Mario; Marcenaro, Emanuela; Castagna, Luca; Lugli, Enrico; Mavilio, Domenico

2018-04-26

Natural Killer cells are the first lymphocyte population to reconstitute early after non myelo-ablative and T cell-replete haploidentical hematopoietic stem cell transplantation with post-transplant infusion of cyclophosphamide. The present study characterizes the transient and predominant expansion starting from the 2nd week after haploidentical hematopoietic stem cell transplantation of a donor-derived unconventional subset of NKp46neg-low/CD56dim/CD16neg natural killer cells expressing remarkable high levels of CD94/NKG2A. Both transcription and phenotypic profiles indicated that unconventional NKp46neg-low/CD56dim/CD16neg natural killer cells are a distinct natural killer cell subpopulation with features of late stage differentiation, yet retaining proliferative capability and functional plasticity to generate conventional NKp46pos/CD56bright/CD16pos natural killer cells in response to interleukin-15 plus interleukin-18. While present at low frequency in healthy donors, unconventional NKp46neg-low/CD56dim/CD16neg natural killer cells are greatly expanded in the following 7 weeks after haploidentical hematopoietic stem cell transplantation and express high levels of the activating receptors NKGD and NKp30 as well as of the lytic granules Granzyme-B and Perforin. Nonetheless, NKp46neg-low/CD56dim/CD16neg natural killer cells displayed a markedly defective cytotoxicity that could be reversed by blocking the inhibitory receptor CD94/NKG2A. These data open new important perspectives to better understand the ontogenesis/homeostasis of human natural killer cells and to develop a novel immune-therapeutic approach that targets the inhibitory NKG2A check point, thus unleashing natural killer cell alloreactivity early after haploidentical hematopoietic stem cell transplantation. Copyright © 2018, Ferrata Storti Foundation.

The B-MYB Transcriptional Network Guides Cell Cycle Progression and Fate Decisions to Sustain Self-Renewal and the Identity of Pluripotent Stem Cells

PubMed Central

Zhan, Ming; Riordon, Daniel R.; Yan, Bin; Tarasova, Yelena S.; Bruweleit, Sarah; Tarasov, Kirill V.; Li, Ronald A.; Wersto, Robert P.; Boheler, Kenneth R.

2012-01-01

Embryonic stem cells (ESCs) are pluripotent and have unlimited self-renewal capacity. Although pluripotency and differentiation have been examined extensively, the mechanisms responsible for self-renewal are poorly understood and are believed to involve an unusual cell cycle, epigenetic regulators and pluripotency-promoting transcription factors. Here we show that B-MYB, a cell cycle regulated phosphoprotein and transcription factor critical to the formation of inner cell mass, is central to the transcriptional and co-regulatory networks that sustain normal cell cycle progression and self-renewal properties of ESCs. Phenotypically, B-MYB is robustly expressed in ESCs and induced pluripotent stem cells (iPSCs), and it is present predominantly in a hypo-phosphorylated state. Knockdown of B-MYB results in functional cell cycle abnormalities that involve S, G2 and M phases, and reduced expression of critical cell cycle regulators like ccnb1 and plk1. By conducting gene expression profiling on control and B-MYB deficient cells, ChIP-chip experiments, and integrative computational analyses, we unraveled a highly complex B-MYB-mediated transcriptional network that guides ESC self-renewal. The network encompasses critical regulators of all cell cycle phases and epigenetic regulators, pluripotency transcription factors, and differentiation determinants. B-MYB along with E2F1 and c-MYC preferentially co-regulate cell cycle target genes. B-MYB also co-targets genes regulated by OCT4, SOX2 and NANOG that are significantly associated with stem cell differentiation, embryonic development, and epigenetic control. Moreover, loss of B-MYB leads to a breakdown of the transcriptional hierarchy present in ESCs. These results coupled with functional studies demonstrate that B-MYB not only controls and accelerates cell cycle progression in ESCs it contributes to fate decisions and maintenance of pluripotent stem cell identity. PMID:22936984

The B-MYB transcriptional network guides cell cycle progression and fate decisions to sustain self-renewal and the identity of pluripotent stem cells.

PubMed

Zhan, Ming; Riordon, Daniel R; Yan, Bin; Tarasova, Yelena S; Bruweleit, Sarah; Tarasov, Kirill V; Li, Ronald A; Wersto, Robert P; Boheler, Kenneth R

2012-01-01

Embryonic stem cells (ESCs) are pluripotent and have unlimited self-renewal capacity. Although pluripotency and differentiation have been examined extensively, the mechanisms responsible for self-renewal are poorly understood and are believed to involve an unusual cell cycle, epigenetic regulators and pluripotency-promoting transcription factors. Here we show that B-MYB, a cell cycle regulated phosphoprotein and transcription factor critical to the formation of inner cell mass, is central to the transcriptional and co-regulatory networks that sustain normal cell cycle progression and self-renewal properties of ESCs. Phenotypically, B-MYB is robustly expressed in ESCs and induced pluripotent stem cells (iPSCs), and it is present predominantly in a hypo-phosphorylated state. Knockdown of B-MYB results in functional cell cycle abnormalities that involve S, G2 and M phases, and reduced expression of critical cell cycle regulators like ccnb1 and plk1. By conducting gene expression profiling on control and B-MYB deficient cells, ChIP-chip experiments, and integrative computational analyses, we unraveled a highly complex B-MYB-mediated transcriptional network that guides ESC self-renewal. The network encompasses critical regulators of all cell cycle phases and epigenetic regulators, pluripotency transcription factors, and differentiation determinants. B-MYB along with E2F1 and c-MYC preferentially co-regulate cell cycle target genes. B-MYB also co-targets genes regulated by OCT4, SOX2 and NANOG that are significantly associated with stem cell differentiation, embryonic development, and epigenetic control. Moreover, loss of B-MYB leads to a breakdown of the transcriptional hierarchy present in ESCs. These results coupled with functional studies demonstrate that B-MYB not only controls and accelerates cell cycle progression in ESCs it contributes to fate decisions and maintenance of pluripotent stem cell identity.

Bone biomaterials and interactions with stem cells

PubMed Central

Gao, Chengde; Peng, Shuping; Feng, Pei; Shuai, Cijun

2017-01-01

Bone biomaterials play a vital role in bone repair by providing the necessary substrate for cell adhesion, proliferation, and differentiation and by modulating cell activity and function. In past decades, extensive efforts have been devoted to developing bone biomaterials with a focus on the following issues: (1) developing ideal biomaterials with a combination of suitable biological and mechanical properties; (2) constructing a cell microenvironment with pores ranging in size from nanoscale to submicro- and microscale; and (3) inducing the oriented differentiation of stem cells for artificial-to-biological transformation. Here we present a comprehensive review of the state of the art of bone biomaterials and their interactions with stem cells. Typical bone biomaterials that have been developed, including bioactive ceramics, biodegradable polymers, and biodegradable metals, are reviewed, with an emphasis on their characteristics and applications. The necessary porous structure of bone biomaterials for the cell microenvironment is discussed, along with the corresponding fabrication methods. Additionally, the promising seed stem cells for bone repair are summarized, and their interaction mechanisms with bone biomaterials are discussed in detail. Special attention has been paid to the signaling pathways involved in the focal adhesion and osteogenic differentiation of stem cells on bone biomaterials. Finally, achievements regarding bone biomaterials are summarized, and future research directions are proposed. PMID:29285402

In the Know and in the News: How Science and the Media Communicate About Stem Cells, Autism and Cerebral Palsy.

PubMed

Sharpe, Kimberly; Di Pietro, Nina; Illes, Judy

2016-02-01

Stem cell research has generated considerable attention for its potential to remediate many disorders of the central nervous system including neurodevelopmental disorders such as autism spectrum disorder (ASD) and cerebral palsy (CP) that place a high burden on individual children, families and society. Here we characterized messaging about the use of stem cells for ASD and CP in news media articles and concurrent dissemination of discoveries through conventional science discourse. We searched LexisNexis and Canadian Newsstand for news articles from the US, UK, Canada and Australia in the period between 2000 and 2014, and PubMed for peer reviewed articles for the same 10 years. Using in-depth content analysis methods, we found less cautionary messaging about stem cells for ASD and CP in the resulting sample of 73 media articles than in the sample of 87 science papers, and a privileging of benefits over risk. News media also present stem cells as ready for clinical application to treat these neurodevelopmental disorders, even while the science literature calls for further research. Investigative news reports that explicitly quote researchers, however, provide the most accurate information to actual science news. The hope, hype, and promise of stem cell interventions for neurodevelopmental disorders, combined with the extreme vulnerability of these children and their families, creates a perfect storm in which journalists and stem cell scientists must commit to a continued, if not even more robust, partnership to promote balanced and accurate messaging.

Characterization of hair-follicle side population cells in mouse epidermis and skin tumors

PubMed Central

Kim, Sun Hye; Sistrunk, Christopher; Miliani de Marval, Paula L.; Rodriguez-Puebla, Marcelo L.

2017-01-01

A subset of cells, termed side-population (SP), which have the ability to efflux Hoeschst 33342, have previously been demonstrated to act as a potential method to isolate stem cells. Numerous stem/progenitor cells have been localized in different regions of the mouse hair follicle (HF). The present study identified a SP in the mouse HF expressing the ABCG2 transporter and MTS24 surface marker. These cells are restricted to the upper isthmus of the HF and have previously been described as progenitor cells. Consistent with their SP characteristic, they demonstrated elevated expression of ABCG2 transporter, which participates in the dye efflux. Analysis of tumor epidermal cell lines revealed a correlation between the number of SP keratinocytes and the grade of malignancy, suggesting that the SP may play a role in malignant progression. Consistent with this idea, the present study observed an increased number of cells expressing ABCG2 and MTS24 in chemically induced skin tumors and skin tumor cell lines. This SP does not express the CD34 surface marker detected in the multipotent stem cells of the bulge region of the HF, which have been defined as tumor initiation cells. The present study concluded that a SP with properties of progenitor cells is localized in the upper isthmus of the HF and is important in mouse skin tumor progression. PMID:29181098

In vitro gamete derivation from pluripotent stem cells: progress and perspective.

PubMed

Nagano, Makoto C

2007-04-01

Germ cells constitute a highly specialized cell population that is indispensable for the continuation and evolution of the species. Recently, several research groups have shown that these unique cells can be produced in vitro from pluripotent stem cells. Furthermore, live births of offspring using induced germ cells have been reported in one study. These results suggest that it may be possible to investigate germ cell development ex vivo and to establish novel reproductive technologies. To this end, it is critical to assess if gamete induction processes in vitro faithfully recapitulate normal germ cell development in vivo. Here, this issue is discussed with a focus on the germ line specification and the sex-specific development of pre- and postnatal germ cells. The aim of this paper is to concisely summarize the past progress and to present some future issues for the investigation into in vitro gamete production from pluripotent stem cells.

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

PubMed

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

2012-01-01

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

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

PubMed

Luo, Mingyue; Chen, Youxin

2018-01-01

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

Comparison of Gene Expression in Human Embryonic Stem Cells, hESC-Derived Mesenchymal Stem Cells and Human Mesenchymal Stem Cells.

PubMed

Barbet, Romain; Peiffer, Isabelle; Hatzfeld, Antoinette; Charbord, Pierre; Hatzfeld, Jacques A

2011-01-01

We present a strategy to identify developmental/differentiation and plasma membrane marker genes of the most primitive human Mesenchymal Stem Cells (hMSCs). Using sensitive and quantitative TaqMan Low Density Arrays (TLDA) methodology, we compared the expression of 381 genes in human Embryonic Stem Cells (hESCs), hESC-derived MSCs (hES-MSCs), and hMSCs. Analysis of differentiation genes indicated that hES-MSCs express the sarcomeric muscle lineage in addition to the classical mesenchymal lineages, suggesting they are more primitive than hMSCs. Transcript analysis of membrane antigens suggests that IL1R1(low), BMPR1B(low), FLT4(low), LRRC32(low), and CD34 may be good candidates for the detection and isolation of the most primitive hMSCs. The expression in hMSCs of cytokine genes, such as IL6, IL8, or FLT3LG, without expression of the corresponding receptor, suggests a role for these cytokines in the paracrine control of stem cell niches. Our database may be shared with other laboratories in order to explore the considerable clinical potential of hES-MSCs, which appear to represent an intermediate developmental stage between hESCs and hMSCs.

Hematopoietic Stem Cell Transplant in Adolescent and Young Adults With Fanconi Anemia Is Feasible With Acceptable Toxicity, With Those Surviving 100 Days Posttransplant Having Excellent Outcomes.

PubMed

Alhuraiji, Ahmad; Alzahrani, Hazza; Al Mohareb, Fahad; Chaudhri, Naeem; Alsharif, Fahad; Mohamed, Said; Rasheed, Walid; Aldawsari, Ghuzayel; Ahmed, Syed Osman; Aljurf, Mahmoud

2016-12-01

Fanconi anemia is a congenital bone marrow failure syndrome that is associated with congenital anomalies and increased risk of cancer. Hematopoietic stem cell transplant is a potentially curative modality for bone marrow failure in Fanconi anemia patients. Here, we report our center's experience regarding adolescent and young adult patients with Fanconi anemia and hematopoietic stem cell transplant. We conducted a retrospective patient record analyses of patients who presented at our center from 1988 to 2014. We included patients greater than 14 years old with confirmed Fanconi anemia based on positive chromosome breakage study and who underwent hematopoietic stem cell transplant at our institution. Our study group comprised 12 patients with Fanconi anemia who underwent hematopoietic stem cell transplant at our institution. The median age was 20 years (range, 14-31 y) with a female predominance of 83%. Low-dose cyclophosphamide (20-80 mg/kg)-based conditioning regimens were used with different combinations that included fludarabine, antithymocyte globulin, or total body irradiation. All patients had HLA-matched sibling grafts. In all patients, stem cell source was the bone marrow. All patients showed engraftment. Four patients (33%) developed acute graft-versus-host disease. Three patients (25%) died early before day 100 after hematopoietic stem cell transplant due to infectious complications, with 1 patient having steroid refractory acute graft-versus-host disease. Overall survival was 75% at a median follow-up of 43 months. All patients who survived are well and remained transfusion independent without evidence of secondary malignancy. Our findings support the feasibility of reduced intensity conditioning allogeneic hematopoietic stem cell transplant in older and more heavily pretreated patients with Fanconi anemia, especially for those who are engrafted.

Flow-Mediated Stem Cell Labeling with Superparamagnetic Iron Oxide Nanoparticle Clusters

PubMed Central

Shkumatov, Artem; Lai, Mei-Hsiu; Smith, Cartney E.; Rich, Max; Kong, Hyunjoon

2013-01-01

This study presents a strategy to enhance the uptake of superparamagnetic iron oxide nanoparticle (SPIO) clusters by manipulating the cellular mechanical environment. Specifically, stem cells exposed to an orbital flow ingested almost two-fold greater amount of SPIO clusters than those cultured statically. Improvements in MR contrast were subsequently achieved for labeled cells in collagen gels and a mouse model. Overall, this strategy will serve to improve the efficiency of cell tracking and therapies. PMID:24033276

Stem cell biology and drug discovery

PubMed Central

2011-01-01

There are many reasons to be interested in stem cells, one of the most prominent being their potential use in finding better drugs to treat human disease. This article focuses on how this may be implemented. Recent advances in the production of reprogrammed adult cells and their regulated differentiation to disease-relevant cells are presented, and diseases that have been modeled using these methods are discussed. Remaining difficulties are highlighted, as are new therapeutic insights that have emerged. PMID:21649940

A comparative study of the structural organization of spheres derived from the adult human subventricular zone and glioblastoma biopsies

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

Vik-Mo, Einar Osland, E-mail: e.o.vik-mo@medisin.uio.no; Department of Neurosurgery, Oslo University Hospital, Oslo; Sandberg, Cecilie

2011-04-15

Sphere forming assays have been useful to enrich for stem like cells in a range of tumors. The robustness of this system contrasts the difficulties in defining a stem cell population based on cell surface markers. We have undertaken a study to describe the cellular and organizational composition of tumorspheres, directly comparing these to neurospheres derived from the adult human subventricular zone (SVZ). Primary cell cultures from brain tumors were found to contain variable fractions of cells positive for tumor stem cell markers (CD133 (2-93%)/SSEA1 (3-15%)/CXCR4 (1-72%)). All cultures produced tumors upon xenografting. Tumorspheres contained a heterogeneous population of cells,more » but were structurally organized with stem cell markers present at the core of spheres, with markers of more mature glial progenitors and astrocytes at more peripheral location. Ultrastructural studies showed that tumorspheres contained a higher fraction of electron dense cells in the core than the periphery (36% and 19%, respectively). Neurospheres also contained a heterogeneous cell population, but did not have an organization similar to tumorspheres. Although tumorspheres clearly display irregular and neoplastic cells, they establish an organized structure with an outward gradient of differentiation. We suggest that this organization is central in maintaining the tumor stem cell pool.« less

Drosophila's contribution to stem cell research.

PubMed

Singh, Gyanesh

2015-01-01

The discovery of Drosophila stem cells with striking similarities to mammalian stem cells has brought new hope for stem cell research. Recent developments in Drosophila stem cell research is bringing wider opportunities for contemporary stem cell biologists. In this regard, Drosophila germ cells are becoming a popular model of stem cell research. In several cases, genes that controlled Drosophila stem cells were later discovered to have functional homologs in mammalian stem cells. Like mammals, Drosophila germline stem cells (GSCs) are controlled by both intrinsic as well as external signals. Inside the Drosophila testes, germline and somatic stem cells form a cluster of cells (the hub). Hub cells depend on JAK-STAT signaling, and, in absence of this signal, they do not self-renew. In Drosophila, significant changes occur within the stem cell niche that contributes to a decline in stem cell number over time. In case of aging Drosophila, somatic niche cells show reduced DE-cadherin and unpaired (Upd) proteins. Unpaired proteins are known to directly decrease stem cell number within the niches, and, overexpression of upd within niche cells restored GSCs in older males also . Stem cells in the midgut of Drosophila are also very promising. Reduced Notch signaling was found to increase the number of midgut progenitor cells. On the other hand, activation of the Notch pathway decreased proliferation of these cells. Further research in this area should lead to the discovery of additional factors that regulate stem and progenitor cells in Drosophila.

Drosophila's contribution to stem cell research

PubMed Central

Singh, Gyanesh

2016-01-01

The discovery of Drosophila stem cells with striking similarities to mammalian stem cells has brought new hope for stem cell research. Recent developments in Drosophila stem cell research is bringing wider opportunities for contemporary stem cell biologists. In this regard, Drosophila germ cells are becoming a popular model of stem cell research. In several cases, genes that controlled Drosophila stem cells were later discovered to have functional homologs in mammalian stem cells. Like mammals, Drosophila germline stem cells (GSCs) are controlled by both intrinsic as well as external signals. Inside the Drosophila testes, germline and somatic stem cells form a cluster of cells (the hub). Hub cells depend on JAK-STAT signaling, and, in absence of this signal, they do not self-renew. In Drosophila, significant changes occur within the stem cell niche that contributes to a decline in stem cell number over time. In case of aging Drosophila, somatic niche cells show reduced DE-cadherin and unpaired (Upd) proteins. Unpaired proteins are known to directly decrease stem cell number within the niches, and, overexpression of upd within niche cells restored GSCs in older males also . Stem cells in the midgut of Drosophila are also very promising. Reduced Notch signaling was found to increase the number of midgut progenitor cells. On the other hand, activation of the Notch pathway decreased proliferation of these cells. Further research in this area should lead to the discovery of additional factors that regulate stem and progenitor cells in Drosophila. PMID:26180635

Efficacy of Human Umbilical Stem Cells Cultured on Polylactic/ Polyglycolic Acid Membrane in the Treatment of Multiple Gingival Recession Defects: a Randomized Controlled Clinical Study

PubMed Central

Zanwar, Kushal; Kumar Ganji, Kiran; Bhongade, Manohar L

2017-01-01

Statement of the Problem: Recently allogenic mesenchymal stem cells are proposed to have multipotential progenitor cell capabilities to differentiate into cementoblasts, osteoblasts, and periodontal ligament fibroblasts. Purpose: The aim of the present study was to compare the efficacy of human umbilical stem cells cultured on polylactic acid (PLA), polyglycolic acid (PGA) membrane with PLA/PGA membrane alone in the treatment of multiple gingival recession defects. Materials and Method: A total number of 14 cases of multiple gingival recession (Miller’s Class I or II) located in the anterior region were randomly selected and divided into test (stem cells in combination with PLA/PGA membrane) and control group (PLA/PGA membrane alone). Clinical parameters including gingival recession, probing pocket depth, clinical attachment level, and width of keratinized gingiva were recorded at baseline, and at 6 months postoperative. Results: At baseline, there was 2.28 mm and 2.14mm mean gingival recession at 16 sites and 14 sites in test and control groups respectively. At 6 months post-surgery, test group showed 1.57 mm mean reduction of gingival recession indicating 66% root coverage, while the control group showed 1.24mm mean reduction of gingival recession indicating 57% root coverage. Conclusion: In the present study, the stem cell with PLA/PGA membrane showed significantly higher mean root coverage compared to only PLA/PGA membrane group. PMID:28620633

Current overview on dental stem cells applications in regenerative dentistry.

PubMed

Bansal, Ramta; Jain, Aditya

2015-01-01

Teeth are the most natural, noninvasive source of stem cells. Dental stem cells, which are easy, convenient, and affordable to collect, hold promise for a range of very potential therapeutic applications. We have reviewed the ever-growing literature on dental stem cells archived in Medline using the following key words: Regenerative dentistry, dental stem cells, dental stem cells banking, and stem cells from human exfoliated deciduous teeth. Relevant articles covering topics related to dental stem cells were shortlisted and the facts are compiled. The objective of this review article is to discuss the history of stem cells, different stem cells relevant for dentistry, their isolation approaches, collection, and preservation of dental stem cells along with the current status of dental and medical applications.

CD34+CD38-CD123+ Cells Are Present in Virtually All Acute Myeloid Leukaemia Blasts: A Promising Single Unique Phenotype for Minimal Residual Disease Detection.

PubMed

Al-Mawali, Adhra; Pinto, Avinash Daniel; Al-Zadjali, Shoaib

In CD34-positive acute myeloid leukaemia (AML), the leukaemia-initiating event likely takes place in the CD34+CD38- cell compartment. CD123 has been shown to be a unique marker of leukaemic stem cells within the CD34+CD38- compartment. The aim of this study was to identify the percentage of CD34+CD38-CD123+ cells in AML blasts, AML CD34+CD38- stem cells, and normal and regenerating bone marrow CD34+CD38- stem cells from non-myeloid malignancies. Thirty-eight adult de novo AML patients with intention to treat were enrolled after the application of inclusion criteria from February 2012 to February 2017. The percentage of the CD34+CD38-CD123+ phenotype in the blast population at diagnosis was determined using a CD45-gating strategy and CD34+ backgating by flow cytometry. We studied the CD34+CD38-CD123+ fraction in AML blasts at diagnosis, and its utility as a unique phenotype for minimal residual disease (MRD) of AML patients. CD123+ cells were present in 97% of AML blasts in patients at diagnosis (median 90%; range 21-99%). CD123+ cells were also present in 97% of the CD34+CD38- compartment (median 0.8164%, range 0.0262-39.7%). Interestingly, CD123 was not present in normal and regenerating CD34+CD38- bone marrow stem cells (range 0.002- 0.067 and 0.004-0.086, respectively). The CD34+CD38-CD123+ phenotype is present in virtually all AML blasts and it may be used as a unique single phenotype for MRD detection in AML patients. © 2017 The Author(s) Published by S. Karger AG, Basel.

The promising potential of menstrual stem cells for antenatal diagnosis and cell therapy.

PubMed

Khoury, Maroun; Alcayaga-Miranda, Francisca; Illanes, Sebastián E; Figueroa, Fernando E

2014-01-01

Menstrual-derived stem cells (MenSCs) are a new source of mesenchymal stem cells isolated from the menstrual fluid. Currently, there is a growing interest in their clinical potential due to fact that they are multipotent, highly proliferative, and easy to obtain in a non-invasive manner. Sampling can be repeated periodically in a simplified and reproducible manner devoid of complications that no existing cell source can match. MenSCs are also free of ethical dilemmas, and display novel properties with regard to presently known adult derived stem cells. This review details their distinctive biological properties regarding immunophenotype and function, proliferation rate, differentiation potential, and paracrine effects mediated by secreted factors. Their possible role in antenatal diagnosis is also discussed. While more insight on their immunomodulatory and diagnostic properties is needed, the impact of clinical and epidemiological factors, such as age, use of contraceptives, or hormonal status still requires further investigations to properly assess their current and future use in clinical application and diagnosis.

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

PubMed

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

2015-12-01

Neural stem cell (NSC)-based therapies offer potential for neural repair in central nervous system (CNS) inflammatory and degenerative disorders. Typically, these conditions present with multifocal CNS lesions making it impractical to inject NSCs locally, thus mandating optimization of vascular delivery of the cells to involved sites. Here, we analyzed NSCs for expression of molecular effectors of cell migration and found that these cells are natively devoid of E-selectin ligands. Using glycosyltransferase-programmed stereosubstitution (GPS), we glycan engineered the cell surface of NSCs ("GPS-NSCs") with resultant enforced expression of the potent E-selectin ligand HCELL (hematopoietic cell E-/L-selectin ligand) and of an E-selectin-binding glycoform of neural cell adhesion molecule ("NCAM-E"). Following intravenous (i.v.) injection, short-term homing studies demonstrated that, compared with buffer-treated (control) NSCs, GPS-NSCs showed greater neurotropism. Administration of GPS-NSC significantly attenuated the clinical course of experimental autoimmune encephalomyelitis (EAE), with markedly decreased inflammation and improved oligodendroglial and axonal integrity, but without evidence of long-term stem cell engraftment. Notably, this effect of NSC is not a universal property of adult stem cells, as administration of GPS-engineered mouse hematopoietic stem/progenitor cells did not improve EAE clinical course. These findings highlight the utility of cell surface glycan engineering to boost stem cell delivery in neuroinflammatory conditions and indicate that, despite the use of a neural tissue-specific progenitor cell population, neural repair in EAE results from endogenous repair and not from direct, NSC-derived cell replacement. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Presence of stem/progenitor cells in the rat penis.

PubMed

Lin, Guiting; Alwaal, Amjad; Zhang, Xiaoyu; Wang, Jianwen; Wang, Lin; Li, Huixi; Wang, Guifang; Ning, Hongxiu; Lin, Ching-Shwun; Xin, Zhongcheng; Lue, Tom F

2015-01-15

Tissue resident stem cells are believed to exist in every organ, and their identification is commonly done using a combination of immunostaining for putative stem cell markers and label-retaining cell (LRC) strategy. In this study, we employed these approaches to identify potential stem cells in the penis. Newborn rats were intraperitoneally injected with thymidine analog, 5-ethynyl-2-deoxyuridine (EdU), and their penis was harvested at 7 h, 3 days, 1 week, and 4 weeks. It was processed for EdU stains and immunofluorescence staining for stem cell markers A2B5, PCNA, and c-kit. EdU-positive cells were counted for each time point and co-localized with each stem cell marker, then isolated and cultured in vitro followed by their characterization using flowcytometry and immunofluorescence. At 7 h post-EdU injection, 410 ± 105.3 penile corporal cells were labeled in each cross-section (∼28%). The number of EdU-positive cells at 3 days increased to 536 ± 115.6, while their percentage dropped to 25%. Progressively fewer EdU-positive cells were present in the sacrificed rat penis at longer time points (1 and 4 weeks). They were mainly distributed in the subtunic and perisinusoidal spaces, and defined as subtunic penile progenitor cells (STPCs) and perisinusoidal penile progenitor cells (PPCs). These cells expressed c-kit, A2B5, and PCNA. After culturing in vitro, only ∼0.324% corporal cells were EdU-labeled LRCs and expressed A2B5/PCNA. Therefore, labeling of penis cells by EdU occurred randomly, and label retaining was not associated with expression of c-kit, A2B5, or PCNA. The penile LRCs are mainly distributed within the subtunic and perisinusoidal space.

Improving the Post-Stroke Therapeutic Potency of Mesenchymal Multipotent Stromal Cells by Cocultivation With Cortical Neurons: The Role of Crosstalk Between Cells.

PubMed

Babenko, Valentina A; Silachev, Denis N; Zorova, Ljubava D; Pevzner, Irina B; Khutornenko, Anastasia A; Plotnikov, Egor Y; Sukhikh, Gennady T; Zorov, Dmitry B

2015-09-01

The goal of the present study was to maximally alleviate the negative impact of stroke by increasing the therapeutic potency of injected mesenchymal multipotent stromal cells (MMSCs). To pursue this goal, the intercellular communications of MMSCs and neuronal cells were studied in vitro. As a result of cocultivation of MMSCs and rat cortical neurons, we proved the existence of intercellular contacts providing transfer of cellular contents from one cell to another. We present evidence of intercellular exchange with fluorescent probes specifically occupied by cytosol with preferential transfer from neurons toward MMSCs. In contrast, we observed a reversed transfer of mitochondria (from MMSCs to neural cells). Intravenous injection of MMSCs in a postischemic period alleviated the pathological indexes of a stroke, expressed as a lower infarct volume in the brain and partial restoration of neurological status. Also, MMSCs after cocultivation with neurons demonstrated more profound neuroprotective effects than did unprimed MMSCs. The production of the brain-derived neurotrophic factor was slightly increased in MMSCs, and the factor itself was redistributed in these cells after cocultivation. The level of Miro1 responsible for intercellular traffic of mitochondria was increased in MMSCs after cocultivation. We conclude that the exchange by cellular compartments between neural and stem cells improves MMSCs' protective abilities for better rehabilitation after stroke. This could be used as an approach to enhance the therapeutic benefits of stem cell therapy to the damaged brain. The idea of priming stem cells before practical use for clinical purposes was applied. Thus, cells were preconditioned by coculturing them with the targeted cells (i.e., neurons for the treatment of brain pathological features) before the transfusion of stem cells to the organism. Such priming improved the capacity of stem cells to treat stroke. Some additional minimal study will be required to develop a detailed protocol for coculturing followed by cell separation. ©AlphaMed Press.