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

PubMed

Nakahara, Taka

2011-07-01

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

Ocular Stem Cell Research from Basic Science to Clinical Application: A Report from Zhongshan Ophthalmic Center Ocular Stem Cell Symposium

PubMed Central

Ouyang, Hong; Goldberg, Jeffrey L.; Chen, Shuyi; Li, Wei; Xu, Guo-Tong; Li, Wei; Zhang, Kang; Nussenblatt, Robert B.; Liu, Yizhi; Xie, Ting; Chan, Chi-Chao; Zack, Donald J.

2016-01-01

Stem cells hold promise for treating a wide variety of diseases, including degenerative disorders of the eye. The eye is an ideal organ for stem cell therapy because of its relative immunological privilege, surgical accessibility, and its being a self-contained system. The eye also has many potential target diseases amenable to stem cell-based treatment, such as corneal limbal stem cell deficiency, glaucoma, age-related macular degeneration (AMD), and retinitis pigmentosa (RP). Among them, AMD and glaucoma are the two most common diseases, affecting over 200 million people worldwide. Recent results on the clinical trial of retinal pigment epithelial (RPE) cells from human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) in treating dry AMD and Stargardt’s disease in the US, Japan, England, and China have generated great excitement and hope. This marks the beginning of the ocular stem cell therapy era. The recent Zhongshan Ophthalmic Center Ocular Stem Cell Symposium discussed the potential applications of various stem cell types in stem cell-based therapies, drug discoveries and tissue engineering for treating ocular diseases. PMID:27102165

Clinical trials for stem cell transplantation: when are they needed?

PubMed

Van Pham, Phuc

2016-04-27

In recent years, both stem cell research and the clinical application of these promising cells have increased rapidly. About 1000 clinical trials using stem cells have to date been performed globally. More importantly, more than 10 stem cell-based products have been approved in some countries. With the rapid growth of stem cell applications, some countries have used clinical trials as a tool to diminish the rate of clinical stem cell applications. However, the point at which stem cell clinical trials are essential remains unclear. This commentary discusses when stem cell clinical trials are essential for stem cell transplantation therapies.

Behavior of stem cells under outer-space microgravity and ground-based microgravity simulation.

PubMed

Zhang, Cui; Li, Liang; Chen, Jianling; Wang, Jinfu

2015-06-01

With rapid development of space engineering, research on life sciences in space is being conducted extensively, especially cellular and molecular studies on space medicine. Stem cells, undifferentiated cells that can differentiate into specialized cells, are considered a key resource for regenerative medicine. Research on stem cells under conditions of microgravity during a space flight or a ground-based simulation has generated several excellent findings. To help readers understand the effects of outer space and ground-based simulation conditions on stem cells, we reviewed recent studies on the effects of microgravity (as an obvious environmental factor in space) on morphology, proliferation, migration, and differentiation of stem cells. © 2015 International Federation for Cell Biology.

Stem Cell Sciences plc.

PubMed

Daniels, Sebnem

2006-09-01

Stem Cell Sciences' core objective is to develop safe and effective stem cell-based therapies for currently incurable diseases. In order to achieve this goal, Stem Cell Sciences recognizes the need for multiple technologies and a globally integrated stem cell initiative. The key challenges for the successful application of stem cells in the clinic is the need for a reproducible supply of pure, fully characterized stem cells that have been grown in suitable conditions for use in the clinic.

miRNA-regulated cancer stem cells: understanding the property and the role of miRNA in carcinogenesis.

PubMed

Chakraborty, Chiranjib; Chin, Kok-Yong; Das, Srijit

2016-10-01

Over the last few years, microRNAs (miRNA)-controlled cancer stem cells have drawn enormous attention. Cancer stem cells are a small population of tumor cells that possess the stem cell property of self-renewal. Recent data shows that miRNA regulates this small population of stem cells. In the present review, we explained different characteristics of cancer stem cells as well as miRNA regulation of self-renewal and differentiation in cancer stem cells. We also described the migration and tumor formation. Finally, we described the different miRNAs that regulate various types of cancer stem cells, such as prostate cancer stem cells, head and neck cancer stem cells, breast cancer stem cells, colorectal cancer stem cells, lung cancer stem cells, gastric cancer stem cells, pancreatic cancer stem cells, etc. Extensive research is needed in order to employ miRNA-based therapeutics to control cancer stem cell population in various cancers in the future.

Engineering Replacement Tissues with Amniotic Stem Cells

DTIC Science & Technology

2012-10-01

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

Reduced hematopoietic stem cell frequency predicts outcome in acute myeloid leukemia.

PubMed

Wang, Wenwen; Stiehl, Thomas; Raffel, Simon; Hoang, Van T; Hoffmann, Isabel; Poisa-Beiro, Laura; Saeed, Borhan R; Blume, Rachel; Manta, Linda; Eckstein, Volker; Bochtler, Tilmann; Wuchter, Patrick; Essers, Marieke; Jauch, Anna; Trumpp, Andreas; Marciniak-Czochra, Anna; Ho, Anthony D; Lutz, Christoph

2017-09-01

In patients with acute myeloid leukemia and low percentages of aldehyde-dehydrogenase-positive cells, non-leukemic hematopoietic stem cells can be separated from leukemic cells. By relating hematopoietic stem cell frequencies to outcome we detected poor overall- and disease-free survival of patients with low hematopoietic stem cell frequencies. Serial analysis of matched diagnostic and follow-up samples further demonstrated that hematopoietic stem cells increased after chemotherapy in patients who achieved durable remissions. However, in patients who eventually relapsed, hematopoietic stem cell numbers decreased dramatically at the time of molecular relapse demonstrating that hematopoietic stem cell levels represent an indirect marker of minimal residual disease, which heralds leukemic relapse. Upon transplantation in immune-deficient mice cases with low percentages of hematopoietic stem cells of our cohort gave rise to leukemic or no engraftment, whereas cases with normal hematopoietic stem cell levels mostly resulted in multi-lineage engraftment. Based on our experimental data, we propose that leukemic stem cells have increased niche affinity in cases with low percentages of hematopoietic stem cells. To validate this hypothesis, we developed new mathematical models describing the dynamics of healthy and leukemic cells under different regulatory scenarios. These models suggest that the mechanism leading to decreases in hematopoietic stem cell frequencies before leukemic relapse must be based on expansion of leukemic stem cells with high niche affinity and the ability to dislodge hematopoietic stem cells. Thus, our data suggest that decreasing numbers of hematopoietic stem cells indicate leukemic stem cell persistence and the emergence of leukemic relapse. Copyright© 2017 Ferrata Storti Foundation.

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

[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.

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.

Aging and stem cell therapy: AMPK as an applicable pharmacological target for rejuvenation of aged stem cells and achieving higher efficacy in stem cell therapy.

PubMed

Khorraminejad-Shirazi, Mohammadhossein; Farahmandnia, Mohammad; Kardeh, Bahareh; Estedlal, Alireza; Kardeh, Sina; Monabati, Ahmad

2017-10-19

In recent years, tissue regeneration has become a promising field for developing stem cell-based transplantation therapies for human patients. Adult stem cells are affected by the same aging mechanisms that involve somatic cells. One of the mechanisms involved in cellular aging is hyperactivation of mechanistic target of rapamycin complex 1 (mTORC1) and disruption of 5' adenosine monophosphate-activated protein kinase (AMPK). Aging of stem cells results in their impaired regenerative capacity and depletion of stem cell pools in adult tissue, which results in lower efficacy of stem cell therapy. By utilizing an effective therapeutic intervention for aged stem cells, stem cell therapy can become more promising for future application. mTORC1 inhibition is a practical approach to preserve the stem cell pool. In this article, we review the dynamic interaction between sirtuin (silent mating type information regulation 2 homolog) 1, AMPK, and mTORC1. We propose that using AMPK activators such as 5-aminoimidazole-4-carboxamide ribonucleotide, A769662, metformin, and oxidized nicotinamide adenine dinucleotide (NAD + ) are practical ways to be employed for achieving better optimized results in stem cell-based transplantation therapies. Copyright © 2017 King Faisal Specialist Hospital & Research Centre. Published by Elsevier B.V. All rights reserved.

The Evolution of the Stem Cell Theory for Heart Failure.

PubMed

Silvestre, Jean-Sébastien; Menasché, Philippe

2015-12-01

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

Stem cells.

PubMed

Behr, Björn; Ko, Sae Hee; Wong, Victor W; Gurtner, Geoffrey C; Longaker, Michael T

2010-10-01

Stem cells are self-renewing cells capable of differentiating into multiple cell lines and are classified according to their origin and their ability to differentiate. Enormous potential exists in use of stem cells for regenerative medicine. To produce effective stem cell-based treatments for a range of diseases, an improved understanding of stem cell biology and better control over stem cell fate are necessary. In addition, the barriers to clinical translation, such as potential oncologic properties of stem cells, need to be addressed. With renewed government support and continued refinement of current stem cell methodologies, the future of stem cell research is exciting and promises to provide novel reconstructive options for patients and surgeons limited by traditional paradigms.

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

PubMed Central

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

2012-01-01

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

Classification of Hydrogels Based on Their Source: A Review and Application in Stem Cell Regulation

NASA Astrophysics Data System (ADS)

Khansari, Maziyar M.; Sorokina, Lioudmila V.; Mukherjee, Prithviraj; Mukhtar, Farrukh; Shirdar, Mostafa Rezazadeh; Shahidi, Mahnaz; Shokuhfar, Tolou

2017-08-01

Stem cells are recognized by their self-renewal ability and can give rise to specialized progeny. Hydrogels are an established class of biomaterials with the ability to control stem cell fate via mechanotransduction. They can mimic various physiological conditions to influence the fate of stem cells and are an ideal platform to support stem cell regulation. This review article provides a summary of recent advances in the application of different classes of hydrogels based on their source (e.g., natural, synthetic, or hybrid). This classification is important because the chemistry of substrate affects stem cell differentiation and proliferation. Natural and synthetic hydrogels have been widely used in stem cell regulation. Nevertheless, they have limitations that necessitate a new class of material. Hybrid hydrogels obtained by manipulation of the natural and synthetic ones can potentially overcome these limitations and shape the future of research in application of hydrogels in stem cell regulation.

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

Present state and future perspectives of using pluripotent stem cells in toxicology research

PubMed Central

Löser, Peter

2011-01-01

The use of novel drugs and chemicals requires reliable data on their potential toxic effects on humans. Current test systems are mainly based on animals or in vitro–cultured animal-derived cells and do not or not sufficiently mirror the situation in humans. Therefore, in vitro models based on human pluripotent stem cells (hPSCs) have become an attractive alternative. The article summarizes the characteristics of pluripotent stem cells, including embryonic carcinoma and embryonic germ cells, and discusses the potential of pluripotent stem cells for safety pharmacology and toxicology. Special attention is directed to the potential application of embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) for the assessment of developmental toxicology as well as cardio- and hepatotoxicology. With respect to embryotoxicology, recent achievements of the embryonic stem cell test (EST) are described and current limitations as well as prospects of embryotoxicity studies using pluripotent stem cells are discussed. Furthermore, recent efforts to establish hPSC-based cell models for testing cardio- and hepatotoxicity are presented. In this context, methods for differentiation and selection of cardiac and hepatic cells from hPSCs are summarized, requirements and implications with respect to the use of these cells in safety pharmacology and toxicology are presented, and future challenges and perspectives of using hPSCs are discussed. PMID:21225242

Cell Based Therapeutic Approach in Vascular Surgery: Application and Review

PubMed Central

Rocca, Aldo; Tafuri, Domenico; Paccone, Marianna; Giuliani, Antonio; Zamboli, Anna Ginevra Immacolata; Surfaro, Giuseppe; Paccone, Andrea; Compagna, Rita; Amato, Maurizo; Serra, Raffaele; Amato, Bruno

2017-01-01

Abstract Multipotent stem cells - such as mesenchymal stem/stromal cells and stem cells derived from different sources like vascular wall are intensely studied to try to rapidly translate their discovered features from bench to bedside. Vascular wall resident stem cells recruitment, differentiation, survival, proliferation, growth factor production, and signaling pathways transduced were analyzed. We studied biological properties of vascular resident stem cells and explored the relationship from several factors as Matrix Metalloproteinases (MMPs) and regulations of biological, translational and clinical features of these cells. In this review we described a translational and clinical approach to Adult Vascular Wall Resident Multipotent Vascular Stem Cells (VW-SCs) and reported their involvement in alternative clinical approach as cells based therapy in vascular disease like arterial aneurysms or peripheral arterial obstructive disease. PMID:29071303

The Challenges of First-in-Human Stem Cell Clinical Trials: What Does This Mean for Ethics and Institutional Review Boards?

PubMed

Barker, Roger A; Carpenter, Melissa K; Forbes, Stuart; Goldman, Steven A; Jamieson, Catriona; Murry, Charles E; Takahashi, Jun; Weir, Gordon

2018-05-08

Stem cell-based clinical interventions are increasingly advancing through preclinical testing and approaching clinical trials. The complexity and diversity of these approaches, and the confusion created by unproven and untested stem cell-based "therapies," create a growing need for a more comprehensive review of these early-stage human trials to ensure they place the patients at minimal risk of adverse events but are also based on solid evidence of preclinical efficacy with a clear scientific rationale for that effect. To address this issue and supplement the independent review process, especially that of the ethics and institutional review boards who may not be experts in stem cell biology, the International Society for Stem Cell Research (ISSCR) has developed a set of practical questions to cover the major issues for which clear evidence-based answers need to be obtained before approving a stem cell-based trial. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Gene therapy and tissue engineering based on muscle-derived stem cells.

PubMed

Deasy, Bridget M; Huard, Johnny

2002-08-01

Skeletal muscle represents a convenient source of stem cells for cell-based tissue and genetic engineering. Muscle-derived stem cells (MDSCs) exhibit both multipotentiality and self-renewal capabilities, and are considered to be distinct from the well-studied satellite cell, another type of muscle stem cell that is capable of self-renewal and myogenic lineage differentiation. The MDSC appears to have less restricted differentiation capabilities as compared with the satellite cell, and may be a precursor of the satellite cell. This review considers the evidence for the existence of MDSCs as well as their origin. We will discuss recent investigations highlighting the potential of stem cell transplantation for the treatment of skeletal, cardiac and smooth muscle injuries and disease. We will highlight challenges in bridging the gap between understanding basic stem cell biology and clinical utilization for cell therapy.

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 cell transplantation therapy for multifaceted therapeutic benefits after stroke.

PubMed

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

2017-10-01

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

A novel intranuclear RNA vector system for long-term stem cell modification

PubMed Central

Ikeda, Yasuhiro; Makino, Akiko; Matchett, William E.; Holditch, Sara J.; Lu, Brian; Dietz, Allan B.; Tomonaga, Keizo

2015-01-01

Genetically modified stem and progenitor cells have emerged as a promising regenerative platform in the treatment of genetic and degenerative disorders, highlighted by their successful therapeutic use in inherent immunodeficiencies. However, biosafety concerns over insertional mutagenesis resulting from integrating recombinant viral vectors have overshadowed the widespread clinical applications of genetically modified stem cells. Here, we report an RNA-based episomal vector system, amenable for long-term transgene expression in stem cells. Specifically, we used a unique intranuclear RNA virus, Borna disease virus (BDV), as the gene transfer vehicle, capable of persistent infections in various cell types. BDV-based vectors allowed for long-term transgene expression in mesenchymal stem cells (MSCs) without affecting cellular morphology, cell surface CD105 expression, or the adipogenicity of MSCs. Similarly, replication-defective BDV vectors achieved long-term transduction of human induced pluripotent stem cells (iPSCs), while maintaining the ability to differentiate into three embryonic germ layers. Thus, the BDV-based vectors offer a genomic modification-free, episomal RNA delivery system for sustained stem cell transduction. PMID:26632671

The evolution of chicken stem cell culture methods.

PubMed

Farzaneh, M; Attari, F; Mozdziak, P E; Khoshnam, S E

2017-12-01

1. The avian embryo is an excellent model for studying embryology and the production of pharmaceutical proteins in transgenic chickens. Furthermore, chicken stem cells have the potential for proliferation and differentiation and emerged as an attractive tool for various cell-based technologies. 2. The objective of these studies is the derivation and culture of these stem cells is the production of transgenic birds for recombinant biomaterials and vaccine manufacture, drug and cytotoxicity testing, as well as to gain insight into basic science, including cell tracking. 3. Despite similarities among the established chicken stem cell lines, fundamental differences have been reported between their culture conditions and applications. Recent conventional protocols used for expansion and culture of chicken stem cells mostly depend on feeder cells, serum-containing media and static culture. 4. Utilising chicken stem cells for generation of cell-based transgenic birds and a variety of vaccines requires large-scale cell production. However, scaling up the conventional adherent chicken stem cells is challenging and labour intensive. Development of a suspension cell culture process for chicken embryonic stem cells (cESCs), chicken primordial germ cells (PGCs) and chicken induced pluripotent stem cells (ciPSCs) will be an important advance for increasing the growth kinetics of these cells. 6. This review describes various approaches and suggestions to achieve optimal cell growth for defined chicken stem cells cultures and use in future manufacturing applications.

Looking into the Future: Toward Advanced 3D Biomaterials for Stem-Cell-Based Regenerative Medicine.

PubMed

Liu, Zhongmin; Tang, Mingliang; Zhao, Jinping; Chai, Renjie; Kang, Jiuhong

2018-04-01

Stem-cell-based therapies have the potential to provide novel solutions for the treatment of a variety of diseases, but the main obstacles to such therapies lie in the uncontrolled differentiation and functional engraftment of implanted tissues. The physicochemical microenvironment controls the self-renewal and differentiation of stem cells, and the key step in mimicking the stem cell microenvironment is to construct a more physiologically relevant 3D culture system. Material-based 3D assemblies of stem cells facilitate the cellular interactions that promote morphogenesis and tissue organization in a similar manner to that which occurs during embryogenesis. Both natural and artificial materials can be used to create 3D scaffolds, and synthetic organic and inorganic porous materials are the two main kinds of artificial materials. Nanotechnology provides new opportunities to design novel advanced materials with special physicochemical properties for 3D stem cell culture and transplantation. Herein, the advances and advantages of 3D scaffold materials, especially with respect to stem-cell-based therapies, are first outlined. Second, the stem cell biology in 3D scaffold materials is reviewed. Third, the progress and basic principles of developing 3D scaffold materials for clinical applications in tissue engineering and regenerative medicine are reviewed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The regulatory sciences for stem cell-based medicinal products.

PubMed

Yuan, Bao-Zhu; Wang, Junzhi

2014-06-01

Over the past few years, several new achievements have been made from stem cell studies, many of which have moved up from preclinical stages to early, or from early to middle or late, stages thanks to relatively safe profile and preliminary evidence of effectiveness. Moreover, some stem cell-based products have been approved for marketing by different national regulatory authorities. However, many critical issues associated mainly with incomplete understanding of stem cell biology and the relevant risk factors, and lack of effective regulations still exist and need to be urgently addressed, especially in countries where establishment of appropriate regulatory system just commenced. More relevantly, the stem cell regulatory sciences need to be established or improved to more effectively evaluate quality, safety and efficacy of stem cell products, and for building up the appropriate regulatory framework. In this review, we summarize some new achievements in stem cell studies, especially the preclinical and clinical studies, the existing regulations, and the associated challenges, and we then propose some considerations for improving stem cell regulatory sciences with a goal of promoting the steadfast growth of the well-regulated stem cell therapies abreast of evolvement of stem cell sciences and technologies.

Stem Cell-Based Therapies for Epidermolysis Bullosa

DTIC Science & Technology

2014-10-01

of human hematopoietic cells for extracellular matrix protein deficiency in epidermolysis bullosa. Stem Cells 2011, 29:900–906. 18. Di Nicola M...promotes cardiogenic gene expression in mesenchymal stem cells. Stem Cell Res Ther 2013, 4:43. 57. Herrmann JL, Wang Y, Abarbanell AM, Weil BR, Tan J

Personalized Regenerative Medicine.

PubMed

Arjmand, Babak; Goodarzi, Parisa; Mohamadi-Jahani, Fereshteh; Falahzadeh, Khadijeh; Larijani, Bagher

2017-03-01

Personalized medicine as a novel field of medicine refers to the prescription of specific therapeutics procedure for an individual. This approach has established based on pharmacogenetic and pharmacogenomic information and data. The terms precision and personalized medicines are sometimes applied interchangeably. However, there has been a shift from "personalized medicine" towards "precision medicine". Although personalized medicine emerged from pharmacogenetics, nowadays it covers many fields of healthcare. Accordingly, regenerative medicine and cellular therapy as the new fields of medicine use cell-based products in order to develop personalized treatments. Different sources of stem cells including mesenchymal stem cells, embryonic stem cells and induced pluripotent stem cells (iPSCs) have been considered in targeted therapies which could give many advantages. iPSCs as the novel and individual pluripotent stem cells have been introduced as the appropriate candidates for personalized cell therapies. Cellular therapies can provide a personalized approach. Because of person-to-person and population differences in the result of stem cell therapy, individualized cellular therapy must be adjusted according to the patient specific profile, in order to achieve best therapeutic results and outcomes. Several factors should be considered to achieve personalized stem cells therapy such as, recipient factors, donor factors, and the overall body environment in which the stem cells could be active and functional. In addition to these factors, the source of stem cells must be carefully chosen based on functional and physical criteria that lead to optimal outcomes.

Cells of Origin of Epithelial Ovarian Cancers

DTIC Science & Technology

2015-09-01

cells in oral squamous cell carcinomas by a novel pathway-based lineage tracing approach in a murine model. ! 13! Specific aims: 1. Determine...SUNDARESAN Lineage tracing and clonal analysis of oral cancer initiating cells The goal of this project is to study cancer stem cells /cancer initiating...whether oral cancer cells genetically marked based on their activities for stem cell -related pathways exhibit cancer stem cell properties in vivo by

The Evolution of the Stem Cell Theory for Heart Failure

PubMed Central

Silvestre, Jean-Sébastien; Menasché, Philippe

2015-01-01

Various stem cell-based approaches for cardiac repair have achieved encouraging results in animal experiments, often leading to their rapid proceeding to clinical testing. However, freewheeling evolutionary developments of the stem cell theory might lead to dystopian scenarios where heterogeneous sources of therapeutic cells could promote mixed clinical outcomes in un-stratified patient populations. This review focuses on the lessons that should be learnt from the first generation of stem cell-based strategies and emphasizes the absolute requirement to better understand the basic mechanisms of stem cell biology and cardiogenesis. We will also discuss about the unexpected “big bang” in the stem cell theory, “blasting” the therapeutic cells to their unchallenged ability to release paracrine factors such as extracellular membrane vesicles. Paradoxically, the natural evolution of the stem cell theory for cardiac regeneration may end with the development of cell-free strategies with multiple cellular targets including cardiomyocytes but also other infiltrating or resident cardiac cells. PMID:26844266

Stem Cell-Based Therapies for Polyglutamine Diseases.

PubMed

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

2018-01-01

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

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.

Stem cells in clinical practice: applications and warnings.

PubMed

Lodi, Daniele; Iannitti, Tommaso; Palmieri, Beniamino

2011-01-17

Stem cells are a relevant source of information about cellular differentiation, molecular processes and tissue homeostasis, but also one of the most putative biological tools to treat degenerative diseases. This review focuses on human stem cells clinical and experimental applications. Our aim is to take a correct view of the available stem cell subtypes and their rational use in the medical area, with a specific focus on their therapeutic benefits and side effects. We have reviewed the main clinical trials dividing them basing on their clinical applications, and taking into account the ethical issue associated with the stem cell therapy. We have searched Pubmed/Medline for clinical trials, involving the use of human stem cells, using the key words "stem cells" combined with the key words "transplantation", "pathology", "guidelines", "properties" and "risks". All the relevant clinical trials have been included. The results have been divided into different categories, basing on the way stem cells have been employed in different pathological conditions.

Recent progress in stem cell differentiation directed by material and mechanical cues.

PubMed

Lin, Xunxun; Shi, Yuan; Cao, Yilin; Liu, Wei

2016-02-02

Stem cells play essential roles in tissue regeneration in vivo via specific lineage differentiation induced by environmental factors. In the past, biochemical signals were the focus of induced stem cell differentiation. As reported by Engler et al (2006 Cell 126 677-89), biophysical signal mediated stem cell differentiation could also serve as an important inducer. With the advancement of material science, it becomes a possible strategy to generate active biophysical signals for directing stem cell fate through specially designed material microstructures. In the past five years, significant progress has been made in this field, and these designed biophysical signals include material elasticity/rigidity, micropatterned structure, extracellular matrix (ECM) coated materials, material transmitted extracellular mechanical force etc. A large number of investigations involved material directed differentiation of mesenchymal stem cells, neural stem/progenitor cells, adipose derived stem cells, hematopoietic stem/progenitor cells, embryonic stem cells and other cells. Hydrogel based materials were commonly used to create varied mechanical properties via modifying the ratio of different components, crosslinking levels, matrix concentration and conjugation with other components. Among them, polyacrylamide (PAM) and polydimethylsiloxane (PDMS) hydrogels remained the major types of material. Specially designed micropatterning was not only able to create a unique topographical surface to control cell shape, alignment, cell-cell and cell-matrix contact for basic stem cell biology study, but also could be integrated with 3D bioprinting to generate micropattered 3D structure and thus to induce stem cell based tissue regeneration. ECM coating on a specific topographical structure was capable of inducing even more specific and potent stem cell differentiation along with soluble factors and mechanical force. The article overviews the progress of the past five years in this particular field.

Rejuvenating the senescent heart

PubMed Central

Nguyen, Nathalie; Sussman, Mark A.

2015-01-01

Purpose of review The purpose of this review is to provide an update on the cardiac stem cell field with an emphasis on aging and to suggest some relevant strategies directed toward rejuvenation of the senescent heart. Recent findings Stem cells were long considered as a fountain of youth and were assumed to be equipped against any form of aging effect. However, it is now clear that stem cells suffer the consequences of aging as well. With the discovery that cardiac stem cells reside in the heart comes the question whether these cells are also impaired upon aging. As cardiac stem cell properties are also altered with age, autologous stem cell-based therapy to treat heart failure will benefit from new improved strategies. Summary With the goal to improve stem cell properties that are impaired upon aging, some strategies are highlighted. Genetic modification of adult human cardiac progenitor cells prior to autologous stem cell-based therapy, delivery of the next generation of stem cells such as CardioChimeras and CardioClusters, and improvement of the myocardial environment with rejuvenating factors constitute some of the possibilities and are discussed in more detail in this review. PMID:25760821

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.

Human Prostate Side Population Cells Demonstrate Stem Cell Properties in Recombination with Urogenital Sinus Mesenchyme

PubMed Central

Foster, Barbara A.; Gangavarapu, Kalyan J.; Mathew, Grinu; Azabdaftari, Gissou; Morrison, Carl D.; Miller, Austin; Huss, Wendy J.

2013-01-01

Stem cell enrichment provides a tool to examine prostate stem cells obtained from benign and malignant tissue. Functional assays can enrich stem cells based on common stem cell phenotypes, such as high ATP binding cassette (ABC) transporter mediated efflux of Hoechst substrates (side population assay). This functional assay is based upon mechanisms that protect cells from environmental insult thus contributing to the survival and protection of the stem cell population. We have isolated and analyzed cells digested from twelve clinical prostate specimens based on the side population assay. Prostate stem cell properties of the isolated cells were tested by serial recombination with rat urogenital mesenchyme. Recombinants with side population cells demonstrate an increase in the frequency of human ductal growth and the number of glands per recombinant when compared to recombinants with non-side population cells. Isolated cells were capable of prostatic growth for up to three generations in the recombination assay with as little as 125 sorted prostate cells. The ability to reproducibly use cells isolated by fluorescence activated cell sorting from human prostate tissue is an essential step to a better understanding of human prostate stem cell biology. ABC transporter G2 (ABCG2) was expressed in recombinants from side population cells indicating the side population cells have self-renewal properties. Epithelial cell differentiation of recombinants was determined by immunohistochemical analysis for expression of the basal, luminal, and neuroendocrine markers, p63, androgen receptor, prostate specific antigen, and chromogranin A, respectively. Thus, the ABCG2 expressing side population demonstrates multipotency and self-renewal properties indicating stem cells are within this population. PMID:23383057

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

PubMed Central

Kaushik, Gaurav; Leijten, Jeroen; Khademhosseini, Ali

2016-01-01

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

Microfluidic systems for stem cell-based neural tissue engineering.

PubMed

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

2016-07-05

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

Watching stem cells at work with a flexible multiphoton tomograph

NASA Astrophysics Data System (ADS)

Uchugonova, Aisada; Hoffmann, Robert; Weinigel, Martin; König, Karsten

2012-03-01

There is a high demand for non-invasive imaging techniques that allow observation of stem cells in their native environment without significant input on cell metabolism, reproduction, and behavior. Easy accessible hair follicle pluripotent stem cells in the bulge area and dermal papilla are potential sources for stem cell based therapy. It has been shown that these cells are able to generate hair, non-follicle skin cells, nerves, vessels, smooth muscles etc. and may participate in wound healing processes. We report on the finding of nestin-GFP expressing stem cells in their native niche in the bulge of the hair follicle of living mice by using high-resolution in-vivo multiphoton tomography. The 3D imaging with submicron resolution was based on two-photon induced fluorescence and second harmonic generation (SHG) of collagen. Migrating stem cells from the bulge to their microenvironment have been detected inside the skin during optical deep tissue sectioning.

Dendrimer-driven neurotrophin expression differs in temporal patterns between rodent and human stem cells.

PubMed

Shakhbazau, Antos; Shcharbin, Dzmitry; Seviaryn, Ihar; Goncharova, Natalya; Kosmacheva, Svetlana; Potapnev, Mihail; Bryszewska, Maria; Kumar, Ranjan; Biernaskie, Jeffrey; Midha, Rajiv

2012-05-07

This study reports the use of a nonviral expression system based on polyamidoamine dendrimers for time-restricted neurotrophin overproduction in mesenchymal stem cells and skin precursor-derived Schwann cells. The dendrimers were used to deliver plasmids for brain-derived neurotrophic factor (BDNF) or neurotrophin-3 (NT-3) expression in both rodent and human stem cells, and the timelines of expression were studied. We have found that, despite the fact that transfection efficiencies and protein expression levels were comparable, dendrimer-driven expression in human mesenchymal stem cells was characterized by a more rapid decline compared to rodent cells. Transient expression systems can be beneficial for some neurotrophins, which were earlier reported to cause unwanted side effects in virus-based long-term expression models. Nonviral neurotrophin expression is a biologically safe and accessible alternative to increase the therapeutic potential of autologous adult stem cells and stem cell-derived functional differentiated cells.

Human Neural Cell-Based Biosensor

DTIC Science & Technology

2011-03-11

following areas: (1) neural progenitor isolation from induced pluripotent stem cells , (2) directed differentiation of progenitors into dopaminergic...from induced pluripotent stem cells , (2) directed differentiation of progenitors into dopaminergic neurons, motoneurons and astrocytes using defined...progenitors from mixed populations, such as induced pluripotent stem cells (iPSCs). We also developed lentiviral based methods to generate iPSCs in

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

PubMed Central

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

2018-01-01

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

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

PubMed

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

2016-09-01

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

Plant stem cells in cosmetics: current trends and future directions

PubMed Central

Trehan, Sonia; Michniak-Kohn, Bozena; Beri, Kavita

2017-01-01

Plant regeneration at the cellular and tissue level is a unique process. Similar to animals, the stem cells in plants have properties that help stimulate and regenerate plants after injury. The unique properties of plant stem cells have been a recent area of interest and focus both in developing new cosmetics and studying how these extracts/phytohormones will influence animal skin. This special report focuses on the current evidence-based trends in plant stem cell-based cosmetics and sheds light on the challenges that we need to overcome in order to see meaningful changes in human skin using topical cosmetics derived from plant stem cells. PMID:29134115

Proinflammatory Stem Cell Signaling in Cardiac Ischemia

PubMed Central

Herrmann, Jeremy L.; Markel, Troy A.; Abarbanell, Aaron M.; Weil, Brent R.; Wang, Meijing; Wang, Yue; Tan, Jiangning

2009-01-01

Abstract Cardiovascular disease remains a leading cause of mortality in developed nations, despite continued advancement in modern therapy. Progenitor and stem cell–based therapy is a novel treatment for cardiovascular disease, and modest benefits in cardiac recovery have been achieved in small clinical trials. This therapeutic modality remains challenged by limitations of low donor-cell survival rates, transient recovery of cardiac function, and the technical difficulty of applying directed cell therapy. Understanding the signaling mechanisms involved in the stem cell response to ischemia has revealed opportunities to modify directly aspects of these pathways to improve their cardioprotective abilities. This review highlights general considerations of stem cell therapy for cardiac disease, reviews the major proinflammatory signaling pathways of mesenchymal stem cells, and reviews ex vivo modifications of stem cells based on these pathways. Antioxid. Redox Signal. 11, 1883–1896. PMID:19187005

TOPICAL REVIEW: Stem cells engineering for cell-based therapy

NASA Astrophysics Data System (ADS)

Taupin, Philippe

2007-09-01

Stem cells carry the promise to cure a broad range of diseases and injuries, from diabetes, heart and muscular diseases, to neurological diseases, disorders and injuries. Significant progresses have been made in stem cell research over the past decade; the derivation of embryonic stem cells (ESCs) from human tissues, the development of cloning technology by somatic cell nuclear transfer (SCNT) and the confirmation that neurogenesis occurs in the adult mammalian brain and that neural stem cells (NSCs) reside in the adult central nervous system (CNS), including that of humans. Despite these advances, there may be decades before stem cell research will translate into therapy. Stem cell research is also subject to ethical and political debates, controversies and legislation, which slow its progress. Cell engineering has proven successful in bringing genetic research to therapy. In this review, I will review, in two examples, how investigators are applying cell engineering to stem cell biology to circumvent stem cells' ethical and political constraints and bolster stem cell research and therapy.

Elucidating the identity and behavior of spermatogenic stem cells in the mouse testis.

PubMed

Yoshida, Shosei

2012-09-01

Spermatogenesis in mice and other mammalians is supported by a robust stem cell system. Stem cells maintain themselves and continue to produce progeny that will differentiate into sperm over a long period. The pioneering studies conducted from the 1950s to the 1970s, which were based largely on extensive morphological analyses, have established the fundamentals of mammalian spermatogenesis and its stem cells. The prevailing so-called A(single) (A(s)) model, which was originally established in 1971, proposes that singly isolated A(s) spermatogonia are in fact the stem cells. In 1994, the first functional stem cell assay was established based on the formation of repopulating colonies after transplantation in germ cell-depleted host testes, which substantially accelerated the understanding of spermatogenic stem cells. However, because testicular tissues are dissociated into single-cell suspension before transplantation, it was impossible to evaluate the A(s) and other classical models solely by this technique. From 2007 onwards, functional assessment of stem cells without destroying the tissue architecture has become feasible by means of pulse-labeling and live-imaging strategies. Results obtained from these experiments have been challenging the classical thought of stem cells, in which stem cells are a limited number of specialized cells undergoing asymmetric division to produce one self-renewing and one differentiating daughter cells. In contrast, the emerging data suggest that an extended and heterogeneous population of cells exhibiting different degrees of self-renewing and differentiating probabilities forms a reversible, flexible, and stochastic stem cell system as a population. These features may lead to establishment of a more universal principle on stem cells that is shared by other systems.

Analysis of Stem Cell Motility In Vivo Based on Immunodetection of Planarian Neoblasts and Tracing of BrdU-Labeled Cells After Partial Irradiation.

PubMed

Tasaki, Junichi; Uchiyama-Tasaki, Chihiro; Rouhana, Labib

2016-01-01

Planarian flatworms have become an important system for the study of stem cell behavior and regulation in vivo. These organisms are able to regenerate any part of their body upon damage or amputation. A crucial cellular event in the process of planarian regeneration is the migration of pluripotent stem cells (known as neoblasts) to the site of injury. Here we describe two approaches for analyzing migration of planarian stem cells to an area where these have been ablated by localized X-ray irradiation. The first approach involves immunolabeling of mitotic neoblasts, while the second is based on tracing stem cells and their progeny after BrdU incorporation. The use of planarians in studies of cell motility is suitable for the identification of factors that influence stem cell migration in vivo and is amenable to RNA interference or pharmacological screening.

Induced pluripotent stem cells: advances to applications

PubMed Central

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

2010-01-01

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

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.

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

PubMed Central

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

2012-01-01

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

Current Technologies Based on the Knowledge of the Stem Cells Microenvironments.

PubMed

Mawad, Damia; Figtree, Gemma; Gentile, Carmine

2017-01-01

The stem cell microenvironment or niche plays a critical role in the regulation of survival, differentiation and behavior of stem cells and their progenies. Recapitulating each aspect of the stem cell niche is therefore essential for their optimal use in in vitro studies and in vivo as future therapeutics in humans. Engineering of optimal conditions for three-dimensional stem cell culture includes multiple transient and dynamic physiological stimuli, such as blood flow and tissue stiffness. Bioprinting and microfluidics technologies, including organs-on-a-chip, are among the most recent approaches utilized to replicate the three-dimensional stem cell niche for human tissue fabrication that allow the integration of multiple levels of tissue complexity, including blood flow. This chapter focuses on the physico-chemical and genetic cues utilized to engineer the stem cell niche and provides an overview on how both bioprinting and microfluidics technologies are improving our knowledge in this field for both disease modeling and tissue regeneration, including drug discovery and toxicity high-throughput assays and stem cell-based therapies in humans.

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

Prospects for neural stem cell-based therapies for neurological diseases.

PubMed

Imitola, Jaime

2007-10-01

Neural stem and progenitor cells have great potential for the treatment of neurological disorders. However, many obstacles remain to translate this field to the patient's bedside, including rationales for using neural stem cells in individual neurological disorders; the challenges of neural stem cell biology; and the caveats of current strategies of isolation and culturing neural precursors. Addressing these challenges is critical for the translation of neural stem cell biology to the clinic. Recent work using neural stem cells has yielded novel biologic concepts such as the importance of the reciprocal interaction between neural stem cells and the neurodegenerative environment. The prospect of using transplants of neural stem cells and progenitors to treat neurological diseases requires a better understanding of the molecular mechanisms of both neural stem cell behavior in experimental models and the intrinsic repair capacity of the injured brain.

Cardiac Progenitor Cells and Bone Marrow-Derived Very Small Embryonic-Like Stem Cells for Cardiac Repair After Myocardial Infarction

PubMed Central

Tang, Xian-Liang; Rokosh, D. Gregg; Guo, Yiru; Bolli, Roberto

2010-01-01

Heart failure after myocardial infarction (MI) continues to be the most prevalent cause of morbidity and mortality worldwide. Although pharmaceutical agents and interventional strategies have contributed greatly to therapy, new and superior treatment modalities are urgently needed given the overall disease burden. Stem cell-based therapy is potentially a promising strategy to lead to cardiac repair after MI. An array of cell types has been explored in this respect, including skeletal myoblasts, bone marrow (BM)-derived stem cells, embryonic stem cells, and more recently, cardiac progenitor cells (CPCs). Recently studies have obtained evidence that transplantation of CPCs or BM-derived very small embryonic-like stem cells can improve cardiac function and alleviate cardiac remodeling, supporting the potential therapeutic utility of these cells for cardiac repair. This report summarizes the current data from those studies and discusses the potential implication of these cells in developing clinically-relevant stem cell-based therapeutic strategies for cardiac regeneration. PMID:20081317

Next Generation Mesenchymal Stem Cell (MSC)–Based Cartilage Repair Using Scaffold-Free Tissue Engineered Constructs Generated with Synovial Mesenchymal Stem Cells

PubMed Central

Shimomura, Kazunori; Ando, Wataru; Moriguchi, Yu; Sugita, Norihiko; Yasui, Yukihiko; Koizumi, Kota; Fujie, Hiromichi; Hart, David A.; Yoshikawa, Hideki

2015-01-01

Because of its limited healing capacity, treatments for articular cartilage injuries are still challenging. Since the first report by Brittberg, autologous chondrocyte implantation has been extensively studied. Recently, as an alternative for chondrocyte-based therapy, mesenchymal stem cell–based therapy has received considerable research attention because of the relative ease in handling for tissue harvest, and subsequent cell expansion and differentiation. This review summarizes latest development of stem cell therapies in cartilage repair with special attention to scaffold-free approaches. PMID:27340513

Effect of aging on stem cells

PubMed Central

Ahmed, Abu Shufian Ishtiaq; Sheng, Matilda HC; Wasnik, Samiksha; Baylink, David J; Lau, Kin-Hing William

2017-01-01

Pluripotent stem cells have the remarkable self-renewal ability and are capable of differentiating into multiple diverse cells. There is increasing evidence that the aging process can have adverse effects on stem cells. As stem cells age, their renewal ability deteriorates and their ability to differentiate into the various cell types is altered. Accordingly, it is suggested aging-induced deterioration of stem cell functions may play a key role in the pathophysiology of the various aging-associated disorders. Understanding the role of the aging process in deterioration of stem cell function is crucial, not only in understanding the pathophysiology of aging-associated disorders, but also in future development of novel effective stem cell-based therapies to treat aging-associated diseases. This review article first focuses on the basis of the various aging disease-related stem cell dysfunction. It then addresses the several concepts on the potential mechanism that causes aging-related stem cell dysfunction. It also briefly discusses the current potential therapies under development for aging-associated stem cell defects. PMID:28261550

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

PubMed

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

2016-12-01

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

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

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.

Stem-Cell Therapy Advances in China.

PubMed

Hu, Lei; Zhao, Bin; Wang, Songlin

2018-02-01

Stem-cell therapy is a promising method for treating patients with a wide range of diseases and injuries. Increasing government funding of scientific research has promoted rapid developments in stem-cell research in China, as evidenced by the substantial increase in the number and quality of publications in the past 5 years. Multiple high-quality studies have been performed in China that concern cell reprogramming, stem-cell homeostasis, gene modifications, and immunomodulation. The number of translation studies, including basic and preclinical investigations, has also increased. Around 100 stem-cell banks have been established in China, 10 stem-cell drugs are currently in the approval process, and >400 stem cell-based clinical trials are currently registered in China. With continued state funding, advanced biotechnical support, and the development of regulatory standards for the clinical application of stem cells, further innovations are expected that will lead to a boom in stem-cell therapies. This review highlights recent achievements in stem-cell research in China and discusses future prospects.

Stem cell regenerative potential combined with nanotechnology and tissue engineering for myocardial regeneration.

PubMed

Calin, Manuela; Stan, Daniela; Simion, Viorel

2013-07-01

The stem cell-based therapy for post-infarction myocardial regeneration has been introduced more than a decade ago, but the functional improvement obtained is limited due to the poor retention and short survival rate of transplanted cells into the damaged myocardium. More recently, the emerging nanotechnology concepts for advanced diagnostics and therapy provide promising opportunities of using stem cells for myocardial regeneration. In this paper will be provided an overview of the use of nanotechnology approaches in stem cell research for: 1) cell labeling to track the distribution of stem cells after transplantation, 2) nanoparticle-mediated gene delivery to stem cells to promote their homing, engraftment, survival and differentiation in the ischemic myocardium and 3) obtaining of bio-inspired materials to provide suitable myocardial scaffolds for delivery of stem cells or stem cell-derived factors.

Chinese newspaper coverage of (unproven) stem cell therapies and their providers.

PubMed

Ogbogu, Ubaka; Du, Li; Rachul, Christen; Bélanger, Lisa; Caulfield, Timothy

2013-04-01

China is a primary destination for stem cell tourism, the phenomenon whereby patients travel abroad to receive unproven stem cell-based treatments that have not been approved in their home countries. Yet, much remains unknown about the state of the stem cell treatment industry in China and about how the Chinese view treatments and providers. Given the media's crucial role in science/health communication and in framing public dialogue, this study sought to examine Chinese newspaper portrayal and perceptions of stem cell treatments and their providers. Based on a content analysis of over 300 newspaper articles, the study revealed that while Chinese newspaper reporting is generally neutral in tone, it is also inaccurate, overly positive, heavily influenced by "interested" treatment providers and focused on the therapeutic uses of stem cells to address the health needs of the local population. The study findings suggest a need to counterbalance providers' influence on media reporting through strategies that encourage media uptake of accurate information about stem cell research and treatments.

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

Nanotechnology and stem cell therapy for cardiovascular diseases: potential applications.

PubMed

La Francesca, Saverio

2012-01-01

The use of stem cell therapy for the treatment of cardiovascular diseases has generated significant interest in recent years. Limitations to the clinical application of this therapy center on issues of stem cell delivery, engraftment, and fate. Nanotechnology-based cell labeling and imaging techniques facilitate stem cell tracking and engraftment studies. Nanotechnology also brings exciting new opportunities to translational stem cell research as it enables the controlled engineering of nanoparticles and nanomaterials that can properly relate to the physical scale of cell-cell and cell-niche interactions. This review summarizes the most relevant potential applications of nanoscale technologies to the field of stem cell therapy for the treatment of cardiovascular diseases.

Mesenchymal Stem Cell Based Therapy for Prostate Cancer

DTIC Science & Technology

2015-11-01

Award Number: W81XWH-13-1-0304 TITLE: Mesenchymal Stem Cell-Based Therapy for Prostate Cancer PRINCIPAL INVESTIGATOR: John Isaacs CONTRACTING...TITLE AND SUBTITLE Mesenchymal Stem Cell-Based Therapy for Prostate Cancer 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-13-1-0304 5c. PROGRAM ELEMENT...effective therapy for castrate resistant metastatic prostate cancer (CRPC). Based upon a substantial published literature from multiple groups, as well as

Eat, breathe, ROS: controlling stem cell fate through metabolism.

PubMed

Kubli, Dieter A; Sussman, Mark A

2017-05-01

Research reveals cardiac regeneration exists at levels previously deemed unattainable. Clinical trials using stem cells demonstrate promising cardiomyogenic and regenerative potential but insufficient contractile recovery. Incomplete understanding of the biology of administered cells likely contributes to inconsistent patient outcomes. Metabolism is a core component of many well-characterized stem cell types, and metabolic changes fundamentally alter stem cell fate from self-renewal to lineage commitment, and vice versa. However, the metabolism of stem cells currently studied for cardiac regeneration remains incompletely understood. Areas covered: Key metabolic features of stem cells are reviewed and unique stem cell metabolic characteristics are discussed. Metabolic changes altering stem cell fate are considered from quiescence and self-renewal to lineage commitment. Key metabolic concepts are applied toward examining cardiac regeneration through stem cell-based approaches, and clinical implications of current cell therapies are evaluated to identify potential areas of improvement. Expert commentary: The metabolism and biology of stem cells used for cardiac therapy remain poorly characterized. A growing appreciation for the fundamental relationship between stem cell functionality and metabolic phenotype is developing. Future studies unraveling links between cardiac stem cell metabolism and regenerative potential may considerably improve treatment strategies and therapeutic outcomes.

Eat, breathe, ROS: controlling stem cell fate through metabolism

PubMed Central

Kubli, Dieter A.; Sussman, Mark A.

2017-01-01

Introduction Research reveals cardiac regeneration exists at levels previously deemed unattainable. Clinical trials using stem cells demonstrate promising cardiomyogenic and regenerative potential but insufficient contractile recovery. Incomplete understanding of the biology of administered cells likely contributes to inconsistent patient outcomes. Metabolism is a core component of many well-characterized stem cell types, and metabolic changes fundamentally alter stem cell fate from self-renewal to lineage commitment, and vice versa. However, the metabolism of stem cells currently studied for cardiac regeneration remains incompletely understood. Areas covered Key metabolic features of stem cells are reviewed and unique stem cell metabolic characteristics are discussed. Metabolic changes altering stem cell fate are considered from quiescence and self-renewal to lineage commitment. Key metabolic concepts are applied toward examining cardiac regeneration through stem cell-based approaches, and clinical implications of current cell therapies are evaluated to identify potential areas of improvement. Expert commentary The metabolism and biology of stem cells used for cardiac therapy remain poorly characterized. A growing appreciation for the fundamental relationship between stem cell functionality and metabolic phenotype is developing. Future studies unraveling links between cardiac stem cell metabolism and regenerative potential may considerably improve treatment strategies and therapeutic outcomes. PMID:28406333

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

PubMed

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

2016-05-01

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

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

Stem cell-based therapies for tumors in the brain: are we there yet?

PubMed Central

Shah, Khalid

2016-01-01

Advances in understanding adult stem cell biology have facilitated the development of novel cell-based therapies for cancer. Recent developments in conventional therapies (eg, tumor resection techniques, chemotherapy strategies, and radiation therapy) for treating both metastatic and primary tumors in the brain, particularly glioblastoma have not resulted in a marked increase in patient survival. Preclinical studies have shown that multiple stem cell types exhibit inherent tropism and migrate to the sites of malignancy. Recent studies have validated the feasibility potential of using engineered stem cells as therapeutic agents to target and eliminate malignant tumor cells in the brain. This review will discuss the recent progress in the therapeutic potential of stem cells for tumors in the brain and also provide perspectives for future preclinical studies and clinical translation. PMID:27282399

Stem cell maintenance by manipulating signaling pathways: past, current and future

PubMed Central

Chen, Xi; Ye, Shoudong; Ying, Qi-Long

2015-01-01

Pluripotent stem cells only exist in a narrow window during early embryonic development, whereas multipotent stem cells are abundant throughout embryonic development and are retainedin various adult tissues and organs. While pluripotent stem cell lines have been established from several species, including mouse, rat, and human, it is still challenging to establish stable multipotent stem cell lines from embryonic or adult tissues. Based on current knowledge, we anticipate that by manipulating extrinsic and intrinsic signaling pathways, most if not all types of stem cells can be maintained in a long-term culture. In this article, we summarize current culture conditions established for the long-term maintenance of authentic pluripotent and multipotent stem cells and the signaling pathways involved. We also discuss the general principles of stem cell maintenance and propose several strategies on the establishment of novel stem cell lines through manipulation of signaling pathways. [BMB Reports 2015; 48(12): 668-676] PMID:26497581

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.

Properties of skin stem cells and their potential clinical applications in modern dermatology.

PubMed

Niezgoda, Anna; Niezgoda, Piotr; Nowowiejska, Laura; Białecka, Agnieszka; Męcińska-Jundziłł, Kaja; Adamska, Urszula; Czajkowski, Rafał

2017-06-01

Stem cells play an important role in medical science, and scientists are investing large sums in order to perform sophisticated studies designed to establish potential clinical applications of stem cells. Growing experience has enabled researchers to determine the precise nature of stem cell division. Although the properties of this particular population of cells have been known and used for some time, mainly with regards to bone marrow-derived mesenchymal stem cell transplantation, we now face a significant challenge in implementing the practical use of skin-derived precursors, making it possible to avoid the necessity for patients to undergo invasive procedures in order to obtain stem cells from bone marrow. Multiple trials have so far been performed, bringing hope for the treatment of disorders previously considered untreatable. Patients suffering from a number of dermatological diseases, including malignant melanoma, systemic lupus erythematosus, vitiligo, alopecia or junctional epidermolysis bullosa, may benefit from treatment based on stem cells. The aim of this review is to summarize available data on stem cells and their potential applications in the treatment of dermatological disorders. The work described is based on data published up to the end of September 2016.

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.

Environmental Impact on Intestinal Stem Cell Functions in Mucosal Homeostasis and Tumorigenesis.

PubMed

Augenlicht, Leonard H

2017-05-01

Multiple cell compartments at or near the base of the intestinal crypt have been identified as contributing intestinal stem cells for homeostasis of the rapidly turning over intestinal mucosa and cells that can initiate tumor development upon appropriate genetic changes. There is a strong literature establishing the importance of the frequently dividing Lgr5+ crypt base columnar cells as the fundamental cell in providing these stem cell-associated functions, but there are also clear data that more quiescent cells from other compartments can be mobilized to provide these stem cell functions upon compromise of Lgr5+ cells. We review the data that vitamin D, a pleiotropic hormone, is essential for Lgr5 stem cell functions by signaling through the vitamin D receptor. Moreover, we discuss the implications of this role of vitamin D and its impact on relatively long-lived stem cells in regards to the fact that virtually all the data on normal functioning of mouse Lgr5 stem cells is derived from mice exposed to vitamin D levels well above those that characterize the human population. Thus, there are still many questions regarding how dietary and environmental factors influence the complement of cells providing stem cell functions and the mechanisms by which this is determined, and the importance of this in human colorectal tumor development. J. Cell. Biochem. 118: 943-952, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Stem cells in degenerative orthopaedic pathologies: effects of aging on therapeutic potential.

PubMed

Atesok, Kivanc; Fu, Freddie H; Sekiya, Ichiro; Stolzing, Alexandra; Ochi, Mitsuo; Rodeo, Scott A

2017-02-01

The purpose of this study was to summarize the current evidence on the use of stem cells in the elderly population with degenerative orthopaedic pathologies and to highlight the pathophysiologic mechanisms behind today's therapeutic challenges in stem cell-based regeneration of destructed tissues in the elderly patients with osteoarthritis (OA), degenerative disc disease (DDD), and tendinopathies. Clinical and basic science studies that report the use of stem cells in the elderly patients with OA, DDD, and tendinopathies were identified using a PubMed search. The studies published in English have been assessed, and the best and most recent evidence was included in the current study. Evidence suggests that, although short-term results regarding the effects of stem cell therapy in degenerative orthopaedic pathologies can be promising, stem cell therapies do not appear to reverse age-related tissue degeneration. Causes of suboptimal outcomes can be attributed to the decrease in the therapeutic potential of aged stem cell populations and the regenerative capacity of these cells, which might be negatively influenced in an aged microenvironment within the degenerated tissues of elderly patients with OA, DDD, and tendinopathies. Clinical protocols guiding the use of stem cells in the elderly patient population are still under development, and high-level randomized controlled trials with long-term outcomes are lacking. Understanding the consequences of age-related changes in stem cell function and responsiveness of the in vivo microenvironment to stem cells is critical when designing cell-based therapies for elderly patients with degenerative orthopaedic pathologies.

Genetic and epigenetic instability of stem cells.

PubMed

Rajamani, Karthyayani; Li, Yuan-Sheng; Hsieh, Dean-Kuo; Lin, Shinn-Zong; Harn, Horng-Jyh; Chiou, Tzyy-Wen

2014-01-01

Recently, research on stem cells has been receiving an increasing amount of attention, both for its advantages and disadvantages. Genetic and epigenetic instabilities among stem cells have been a recurring obstacle to progress in regenerative medicine using stem cells. Various reports have stated that these instabilities can transform stem cells when transferred in vivo and thus have the potential to develop tumors. Previous research has shown that various extrinsic and intrinsic factors can contribute to the stability of stem cells. The extrinsic factors include growth supplements, growth factors, oxygen tension, passage technique, and cryopreservation. Controlling these factors based on previous reports may assist researchers in developing strategies for the production and clinical application of "safe" stem cells. On the other hand, the intrinsic factors can be unpredictable and uncontrollable; therefore, to ensure the successful use of stem cells in regenerative medicine, it is imperative to develop and implement appropriate strategies and technique for culturing stem cells and to confirm the genetic and epigenetic safety of these stem cells before employing them in clinical trials.

Engineering three dimensional micro nerve tissue using postnatal stem cells from human dental apical papilla.

PubMed

Kim, Byung-Chul; Jun, Sung-Min; Kim, So Yeon; Kwon, Yong-Dae; Choe, Sung Chul; Kim, Eun-Chul; Lee, Jae-Hyung; Kim, Jinseok; Suh, Jun-Kyo Francis; Hwang, Yu-Shik

2017-04-01

The in vitro generation of cell-based three dimensional (3D) nerve tissue is an attractive subject to improve graft survival and integration into host tissue for neural tissue regeneration or to model biological events in stem cell differentiation. Although 3D organotypic culture strategies are well established for 3D nerve tissue formation of pluripotent stem cells to study underlying biology in nerve development, cell-based nerve tissues have not been developed using human postnatal stem cells with therapeutic potential. Here, we established a culture strategy for the generation of in vitro cell-based 3D nerve tissue from postnatal stem cells from apical papilla (SCAPs) of teeth, which originate from neural crest-derived ectomesenchyme cells. A stem cell population capable of differentiating into neural cell lineages was generated during the ex vivo expansion of SCAPs in the presence of EGF and bFGF, and SCAPs differentiated into neural cells, showing neural cell lineage-related molecular and gene expression profiles, morphological changes and electrophysical property under neural-inductive culture conditions. Moreover, we showed the first evidence that 3D cell-based nerve-like tissue with axons and myelin structures could be generated from SCAPs via 3D organotypic culture using an integrated bioprocess composed of polyethylene glycol (PEG) microwell-mediated cell spheroid formation and subsequent dynamic culture in a high aspect ratio vessel (HARV) bioreactor. In conclusion, the culture strategy in our study provides a novel approach to develop in vitro engineered nerve tissue using SCAPs and a foundation to study biological events in the neural differentiation of postnatal stem cells. Biotechnol. Bioeng. 2017;114: 903-914. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Stem Cells in the Trabecular Meshwork for Regulating Intraocular Pressure.

PubMed

Yun, Hongmin; Zhou, Yi; Wills, Andrew; Du, Yiqin

2016-06-01

Intraocular pressure (IOP) is still the main treatment target for glaucoma. Outflow resistance mainly exists at the trabecular meshwork (TM) outflow pathway, which is responsible for IOP regulation. Changes of TM cellularity and TM extracellular matrix turnover may play important roles in IOP regulation. In this article, we review basic anatomy and physiology of the outflow pathway and TM stem cell characteristics regarding the location, isolation, identification and function. TM stem cells are localized at the insert region of the TM and are label-retaining in vivo. They can be isolated by side-population cell sorting, cloning culture, or sphere culture. TM stem cells are multipotent with the ability to home to the TM region and differentiate into TM cells in vivo. Other stem cell types, such as adipose-derived stem cells, mesenchymal stem cells and induced pluripotent stem cells have been discovered for TM cell differentiation and TM regeneration. We also review glaucomatous animal models, which are suitable to study stem cell-based therapies for TM regeneration.

Stem Cells in the Trabecular Meshwork for Regulating Intraocular Pressure

PubMed Central

Yun, Hongmin; Zhou, Yi; Wills, Andrew

2016-01-01

Abstract Intraocular pressure (IOP) is still the main treatment target for glaucoma. Outflow resistance mainly exists at the trabecular meshwork (TM) outflow pathway, which is responsible for IOP regulation. Changes of TM cellularity and TM extracellular matrix turnover may play important roles in IOP regulation. In this article, we review basic anatomy and physiology of the outflow pathway and TM stem cell characteristics regarding the location, isolation, identification and function. TM stem cells are localized at the insert region of the TM and are label-retaining in vivo. They can be isolated by side-population cell sorting, cloning culture, or sphere culture. TM stem cells are multipotent with the ability to home to the TM region and differentiate into TM cells in vivo. Other stem cell types, such as adipose-derived stem cells, mesenchymal stem cells and induced pluripotent stem cells have been discovered for TM cell differentiation and TM regeneration. We also review glaucomatous animal models, which are suitable to study stem cell-based therapies for TM regeneration. PMID:27183473

StemTextSearch: Stem cell gene database with evidence from abstracts.

PubMed

Chen, Chou-Cheng; Ho, Chung-Liang

2017-05-01

Previous studies have used many methods to find biomarkers in stem cells, including text mining, experimental data and image storage. However, no text-mining methods have yet been developed which can identify whether a gene plays a positive or negative role in stem cells. StemTextSearch identifies the role of a gene in stem cells by using a text-mining method to find combinations of gene regulation, stem-cell regulation and cell processes in the same sentences of biomedical abstracts. The dataset includes 5797 genes, with 1534 genes having positive roles in stem cells, 1335 genes having negative roles, 1654 genes with both positive and negative roles, and 1274 with an uncertain role. The precision of gene role in StemTextSearch is 0.66, and the recall is 0.78. StemTextSearch is a web-based engine with queries that specify (i) gene, (ii) category of stem cell, (iii) gene role, (iv) gene regulation, (v) cell process, (vi) stem-cell regulation, and (vii) species. StemTextSearch is available through http://bio.yungyun.com.tw/StemTextSearch.aspx. Copyright © 2017. Published by Elsevier Inc.

Stem cell-based gene therapy activated using magnetic hyperthermia to enhance the treatment of cancer

PubMed Central

Yin, Perry T.; Shah, Shreyas; Pasquale, Nicholas J.; Garbuzenko, Olga B.; Minko, Tamara; Lee, Ki-Bum

2015-01-01

Stem cell-based gene therapies, wherein stem cells are genetically engineered to express therapeutic molecules, have shown tremendous potential for cancer applications owing to their innate ability to home to tumors. However, traditional stem cell-based gene therapies are hampered by our current inability to control when the therapeutic genes are actually turned on, thereby resulting in detrimental side effects. Here, we report the novel application of magnetic core-shell nanoparticles for the dual purpose of delivering and activating a heat-inducible gene vector that encodes TNF-related apoptosis-inducing ligand (TRAIL) in adipose-derived mesenchymal stem cells (AD-MSCs). By combining the tumor tropism of the AD-MSCs with the spatiotemporal MCNP-based delivery and activation of TRAIL expression, this platform provides an attractive means with which to enhance our control over the activation of stem cell-based gene therapies. In particular, we found that these engineered AD-MSCs retained their innate ability to proliferate, differentiate, and, most importantly, home to tumors, making them ideal cellular carriers. Moreover, exposure of the engineered AD-MSCS to mild magnetic hyperthermia resulted in the selective expression of TRAIL from the engineered AD-MSCs and, as a result, induced significant ovarian cancer cell death in vitro and in vivo. PMID:26720500

Stem cell-based gene therapy activated using magnetic hyperthermia to enhance the treatment of cancer.

PubMed

Yin, Perry T; Shah, Shreyas; Pasquale, Nicholas J; Garbuzenko, Olga B; Minko, Tamara; Lee, Ki-Bum

2016-03-01

Stem cell-based gene therapies, wherein stem cells are genetically engineered to express therapeutic molecules, have shown tremendous potential for cancer applications owing to their innate ability to home to tumors. However, traditional stem cell-based gene therapies are hampered by our current inability to control when the therapeutic genes are actually turned on, thereby resulting in detrimental side effects. Here, we report the novel application of magnetic core-shell nanoparticles for the dual purpose of delivering and activating a heat-inducible gene vector that encodes TNF-related apoptosis-inducing ligand (TRAIL) in adipose-derived mesenchymal stem cells (AD-MSCs). By combining the tumor tropism of the AD-MSCs with the spatiotemporal MCNP-based delivery and activation of TRAIL expression, this platform provides an attractive means with which to enhance our control over the activation of stem cell-based gene therapies. In particular, we found that these engineered AD-MSCs retained their innate ability to proliferate, differentiate, and, most importantly, home to tumors, making them ideal cellular carriers. Moreover, exposure of the engineered AD-MSCS to mild magnetic hyperthermia resulted in the selective expression of TRAIL from the engineered AD-MSCs and, as a result, induced significant ovarian cancer cell death in vitro and in vivo. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comprehensive analysis of miRNAs expression profiles revealed potential key miRNA/mRNAs regulating colorectal cancer stem cell self-renewal.

PubMed

Xu, Peng; Wang, Junhua; Sun, Bo; Xiao, Zhongdang

2018-05-20

Self-renewal is essential for the malignant biological behaviors of colorectal cancer stem cells. While the self-renewal molecular mechanisms of colorectal cancer stem cells are not yet fully understood. Recently, miRNAs are reported to be relevant to the self-renewal ability of cancer stem cells. In this study, we first isolated colorectal cancer stem cell from colorectal cancer cell line HCT-116 by 1% low serum culture. Then we conducted a comprehensive analysis based on the miRNAs profiles data of both colorectal cancer stem cells and normal cultured colorectal cancer cells. Pathway analysis revealed multiple pathways including Jak-STAT, TGF-beta, PI3K-Akt and MAPK signaling pathway that are correlated to colorectal cancer. Further, we constructed a miRNA-mRNA network, based on which, several miRNA/mRNA pairs were ranked according to their impact index to the self-renewal of colorectal cancer stem cells. Further biological experiment showed that up-regulation of miR-92a-3p led to cell cycle arrest and reduced colony formation. This work provides clues to find the new potential biomarkers for colorectal cancer stem cell diagnosis and select effective miRNAs for targeted therapy. Copyright © 2018 Elsevier B.V. All rights reserved.

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.

Recent Progress in Stem Cell Modification for Cardiac Regeneration

PubMed Central

Voronina, Natalia; Steinhoff, Gustav

2018-01-01

During the past decades, stem cell-based therapy has acquired a promising role in regenerative medicine. The application of novel cell therapeutics for the treatment of cardiovascular diseases could potentially achieve the ambitious aim of effective cardiac regeneration. Despite the highly positive results from preclinical studies, data from phase I/II clinical trials are inconsistent and the improvement of cardiac remodeling and heart performance was found to be quite limited. The major issues which cardiac stem cell therapy is facing include inefficient cell delivery to the site of injury, accompanied by low cell retention and weak effectiveness of remaining stem cells in tissue regeneration. According to preclinical and clinical studies, various stem cells (adult stem cells, embryonic stem cells, and induced pluripotent stem cells) represent the most promising cell types so far. Beside the selection of the appropriate cell type, researchers have developed several strategies to produce “second-generation” stem cell products with improved regenerative capacity. Genetic and nongenetic modifications, chemical and physical preconditioning, and the application of biomaterials were found to significantly enhance the regenerative capacity of transplanted stem cells. In this review, we will give an overview of the recent developments in stem cell engineering with the goal to facilitate stem cell delivery and to promote their cardiac regenerative activity. PMID:29535769

Adult mesenchymal stem cells and cell-based tissue engineering

PubMed Central

Tuan, Rocky S; Boland, Genevieve; Tuli, Richard

2003-01-01

The identification of multipotential mesenchymal stem cells (MSCs) derived from adult human tissues, including bone marrow stroma and a number of connective tissues, has provided exciting prospects for cell-based tissue engineering and regeneration. This review focuses on the biology of MSCs, including their differentiation potentials in vitro and in vivo, and the application of MSCs in tissue engineering. Our current understanding of MSCs lags behind that of other stem cell types, such as hematopoietic stem cells. Future research should aim to define the cellular and molecular fingerprints of MSCs and elucidate their endogenous role(s) in normal and abnormal tissue functions. PMID:12716446

Early Intervention Stem Cell-Based Therapy (EISCBT) for Corneal Burns and Trauma

DTIC Science & Technology

2015-10-01

be held in place on the cornea by a soft contact lens. We will optimize means of storing the ReCoBand frozen so they will be available to doctors... regeneration in vivo Task 3. Assess plastic compressed collagen as a stem cell delivery vehicle Task 4. Assess cell sheets as delivery vehicle for stem...Stromal Stem Cells (CSSC) are obtained from biopsies of corneal tissue . The quality and potency of individual stem cell lines varies greatly from one

The Role of Stem Cells in Aesthetic Surgery: Fact or Fiction?

PubMed Central

McArdle, Adrian; Senarath-Yapa, Kshemendra; Walmsley, Graham G.; Hu, Michael; Atashroo, David A.; Tevlin, Ruth; Zielins, Elizabeth; Gurtner, Geoffrey C.; Wan, Derrick C.; Longaker, Michael T.

2014-01-01

Stem cells are attractive candidates for the development of novel therapies, targeting indications that involve functional restoration of defective tissue. Although most stem cell therapies are new and highly experimental, there are clinics around the world that exploit vulnerable patients with the hope of offering supposed stem cell therapies, many of which operate without credible scientific merit, oversight, or other patient protection. We review the potential, as well as drawbacks, for incorporation of stem cells in cosmetic procedures. A review of FDA-approved indications and ongoing clinical trials with adipose stem cells is provided. Furthermore, a “snapshot” analysis of websites using the search terms “stem cell therapy” or “stem cell treatment” or “stem cell facelift” was performed. Despite the protective net cast by regulatory agencies such as the FDA and professional societies such as the American Society of Plastic Surgeons, we are witnessing worrying advertisements for procedures such as stem cell facelifts, stem cell breast augmentations, and even stem cell vaginal rejuvenation. The marketing and promotion of stem cell procedures in aesthetic surgery is not adequately supported by clinical evidence in the majority of cases. Stem cells offer tremendous potential, but the marketplace is saturated with unsubstantiated and sometimes fraudulent claims that may place patients at risk. With plastic surgeons at the forefront of stem cell-based regenerative medicine, it is critically important that we provide an example of a rigorous approach to research, data collection, and advertising of stem cell therapies. PMID:24732654

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

Induction of muscle stem cell quiescence by the secreted niche factor Oncostatin M.

PubMed

Sampath, Srinath C; Sampath, Srihari C; Ho, Andrew T V; Corbel, Stéphane Y; Millstone, Joshua D; Lamb, John; Walker, John; Kinzel, Bernd; Schmedt, Christian; Blau, Helen M

2018-04-18

The balance between stem cell quiescence and proliferation in skeletal muscle is tightly controlled, but perturbed in a variety of disease states. Despite progress in identifying activators of stem cell proliferation, the niche factor(s) responsible for quiescence induction remain unclear. Here we report an in vivo imaging-based screen which identifies Oncostatin M (OSM), a member of the interleukin-6 family of cytokines, as a potent inducer of muscle stem cell (MuSC, satellite cell) quiescence. OSM is produced by muscle fibers, induces reversible MuSC cell cycle exit, and maintains stem cell regenerative capacity as judged by serial transplantation. Conditional OSM receptor deletion in satellite cells leads to stem cell depletion and impaired regeneration following injury. These results identify Oncostatin M as a secreted niche factor responsible for quiescence induction, and for the first time establish a direct connection between induction of quiescence, stemness, and transplantation potential in solid organ stem cells.

Stem Cell Therapy for Erectile Dysfunction.

PubMed

Matz, Ethan L; Terlecki, Ryan; Zhang, Yuanyuan; Jackson, John; Atala, Anthony

2018-04-06

The prevalence of erectile dysfunction (ED) is substantial and continues to rise. Current therapeutics for ED consist of oral medications, intracavernosal injections, vacuum erection devices, and penile implants. While such options may manage the disease state, none of these modalities, however, restore function. Stem cell therapy has been evaluated for erectile restoration in animal models. These cells have been derived from multiple tissues, have varied potential, and may function via local engraftment or paracrine signaling. Bone marrow-derived stem cells (BMSC) and adipose-derived stem cells (ASC) have both been used in these models with noteworthy effects. Herein, we will review the pathophysiology of ED, animal models, current and novel stem-cell based therapeutics, clinical trials and areas for future research. The relevant literature and contemporary data using keywords, "stem cells and erectile dysfunction" was reviewed. Examination of evidence supporting the association between erectile dysfunction and adipose derived stem cells, bone marrow derived stem cells, placental stem cells, urine stem cells and stem cell therapy respectively. Placental-derived stem cells and urine-derived stem cells possess many similar properties as BMSC and ASC, but the methods of acquisition are favorable. Human clinical trials have already demonstrated successful use of stem cells for improvement of erectile function. The future of stem cell research is constantly being evaluated, although, the evidence suggests a place for stem cells in erectile dysfunction therapeutics. Matz EL, Terlecki R, Zhang Y, et al. Stem Cell Therapy for Erectile Dysfunction. Sex Med Rev 2018;XX:XXX-XXX. Copyright © 2018 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Imaging Stem Cells Implanted in Infarcted Myocardium

PubMed Central

Zhou, Rong; Acton, Paul D.; Ferrari, Victor A.

2008-01-01

Stem cell–based cellular cardiomyoplasty represents a promising therapy for myocardial infarction. Noninvasive imaging techniques would allow the evaluation of survival, migration, and differentiation status of implanted stem cells in the same subject over time. This review describes methods for cell visualization using several corresponding noninvasive imaging modalities, including magnetic resonance imaging, positron emission tomography, single-photon emission computed tomography, and bioluminescent imaging. Reporter-based cell visualization is compared with direct cell labeling for short- and long-term cell tracking. PMID:17112999

Physicochemical Control of Adult Stem Cell Differentiation: Shedding Light on Potential Molecular Mechanisms

DTIC Science & Technology

2010-01-01

stem - cell -based biomedical and therapeutic applications, including tissue engineering, requires an understanding of the cell-cell and cell-environment interactions. To this end, recent efforts have been focused on the manipulation of adult stem cell differentiation using inductive soluble factors, designing suitable mechanical environments, and applying noninvasive physical forces. Although each of these different approaches has been successfully applied to regulate stem cell differentiation, it would be of great interest and

Identification of Regulatory Factors for Mesenchymal Stem Cell-Derived Salivary Epithelial Cells in a Co-Culture System

PubMed Central

Park, Yun-Jong; Koh, Jin; Gauna, Adrienne E.; Chen, Sixue; Cha, Seunghee

2014-01-01

Patients with Sjögren’s syndrome or head and neck cancer patients who have undergone radiation therapy suffer from severe dry mouth (xerostomia) due to salivary exocrine cell death. Regeneration of the salivary glands requires a better understanding of regulatory mechanisms by which stem cells differentiate into exocrine cells. In our study, bone marrow-derived mesenchymal stem cells were co-cultured with primary salivary epithelial cells from C57BL/6 mice. Co-cultured bone marrow-derived mesenchymal stem cells clearly resembled salivary epithelial cells, as confirmed by strong expression of salivary gland epithelial cell-specific markers, such as alpha-amylase, muscarinic type 3 receptor, aquaporin-5, and cytokeratin 19. To identify regulatory factors involved in this differentiation, transdifferentiated mesenchymal stem cells were analyzed temporarily by two-dimensional-gel-electrophoresis, which detected 58 protein spots (>1.5 fold change, p<0.05) that were further categorized into 12 temporal expression patterns. Of those proteins only induced in differentiated mesenchymal stem cells, ankryin-repeat-domain-containing-protein 56, high-mobility-group-protein 20B, and transcription factor E2a were selected as putative regulatory factors for mesenchymal stem cell transdifferentiation based on putative roles in salivary gland development. Induction of these molecules was confirmed by RT-PCR and western blotting on separate sets of co-cultured mesenchymal stem cells. In conclusion, our study is the first to identify differentially expressed proteins that are implicated in mesenchymal stem cell differentiation into salivary gland epithelial cells. Further investigation to elucidate regulatory roles of these three transcription factors in mesenchymal stem cell reprogramming will provide a critical foundation for a novel cell-based regenerative therapy for patients with xerostomia. PMID:25402494

Pluripotent Stem Cells and Gene Therapy

PubMed Central

Simara, Pavel; Motl, Jason A.; Kaufman, Dan S.

2013-01-01

Human pluripotent stem cells represent an accessible cell source for novel cell-based clinical research and therapies. With the realization of induced pluripotent stem cells (iPSCs), it is possible to produce almost any desired cell type from any patient's cells. Current developments in gene modification methods have opened the possibility for creating genetically corrected human iPSCs for certain genetic diseases that could be used later in autologous transplantation. Promising preclinical studies have demonstrated correction of disease-causing mutations in a number of hematological, neuronal and muscular disorders. This review aims to summarize these recent advances with a focus on iPSC generation techniques, as well as gene modification methods. We will then further discuss some of the main obstacles remaining to be overcome before successful application of human pluripotent stem cell-based therapy arrives in the clinic and what the future of stem cell research may look like. PMID:23353080

Stem cell tourism and public education: the missing elements.

PubMed

Master, Zubin; Robertson, Kelsey; Frederick, Daniel; Rachul, Christen; Caulfield, Timothy

2014-09-04

Stem cell tourism describes the Internet-based industry where in patients receive unproven stem cell interventions. To better inform the public, several organizations provide educational material on stem cell therapies and tourism; however, an assessment of the currently available resources reveals a lack of comprehensive information, suggesting that further efforts are needed. Copyright © 2014 Elsevier Inc. All rights reserved.

Technology advancement for integrative stem cell analyses.

PubMed

Jeong, Yoon; Choi, Jonghoon; Lee, Kwan Hyi

2014-12-01

Scientists have endeavored to use stem cells for a variety of applications ranging from basic science research to translational medicine. Population-based characterization of such stem cells, while providing an important foundation to further development, often disregard the heterogeneity inherent among individual constituents within a given population. The population-based analysis and characterization of stem cells and the problems associated with such a blanket approach only underscore the need for the development of new analytical technology. In this article, we review current stem cell analytical technologies, along with the advantages and disadvantages of each, followed by applications of these technologies in the field of stem cells. Furthermore, while recent advances in micro/nano technology have led to a growth in the stem cell analytical field, underlying architectural concepts allow only for a vertical analytical approach, in which different desirable parameters are obtained from multiple individual experiments and there are many technical challenges that limit vertically integrated analytical tools. Therefore, we propose--by introducing a concept of vertical and horizontal approach--that there is the need of adequate methods to the integration of information, such that multiple descriptive parameters from a stem cell can be obtained from a single experiment.

Technology Advancement for Integrative Stem Cell Analyses

PubMed Central

Jeong, Yoon

2014-01-01

Scientists have endeavored to use stem cells for a variety of applications ranging from basic science research to translational medicine. Population-based characterization of such stem cells, while providing an important foundation to further development, often disregard the heterogeneity inherent among individual constituents within a given population. The population-based analysis and characterization of stem cells and the problems associated with such a blanket approach only underscore the need for the development of new analytical technology. In this article, we review current stem cell analytical technologies, along with the advantages and disadvantages of each, followed by applications of these technologies in the field of stem cells. Furthermore, while recent advances in micro/nano technology have led to a growth in the stem cell analytical field, underlying architectural concepts allow only for a vertical analytical approach, in which different desirable parameters are obtained from multiple individual experiments and there are many technical challenges that limit vertically integrated analytical tools. Therefore, we propose—by introducing a concept of vertical and horizontal approach—that there is the need of adequate methods to the integration of information, such that multiple descriptive parameters from a stem cell can be obtained from a single experiment. PMID:24874188

Pediatric Glioblastoma Therapies Based on Patient-Derived Stem Cell Resources

DTIC Science & Technology

2012-09-01

cells, to evaluate whether pediatric tumor will have fundamental different responses to the new therapeutic regimes. Since glioma stem cell lines have...glioma stem cell lines and has begun molecular and phenotypic characterization of these lines. This characterization has included analysis of gene

Development of tyrosinase-based reporter genes for preclinical photoacoustic imaging of mesenchymal stem cells

NASA Astrophysics Data System (ADS)

Märk, Julia; Ruschke, Karen; Dortay, Hakan; Schreiber, Isabelle; Sass, Andrea; Qazi, Taimoor; Pumberger, Matthias; Laufer, Jan

2014-03-01

The capability to image stem cells in vivo in small animal models over extended periods of time is important to furthering our understanding of the processes involved in tissue regeneration. Photoacoustic imaging is suited to this application as it can provide high resolution (tens of microns) absorption-based images of superficial tissues (cm depths). However, stem cells are rare, highly migratory, and can divide into more specialised cells. Genetic labelling strategies are therefore advantageous for their visualisation. In this study, methods for the transfection and viral transduction of mesenchymal stem cells with reporter genes for the co-expression of tyrosinase and a fluorescent protein (mCherry). Initial photoacoustic imaging experiments of tyrosinase expressing cells in small animal models of tissue regeneration were also conducted. Lentiviral transduction methods were shown to result in stable expression of tyrosinase and mCherry in mesenchymal stem cells. The results suggest that photoacoustic imaging using reporter genes is suitable for the study of stem cell driven tissue regeneration in small animals.

Engineering Approaches Toward Deconstructing and Controlling the Stem Cell Environment

PubMed Central

Edalat, Faramarz; Bae, Hojae; Manoucheri, Sam; Cha, Jae Min; Khademhosseini, Ali

2012-01-01

Stem cell-based therapeutics have become a vital component in tissue engineering and regenerative medicine. The microenvironment within which stem cells reside, i.e. the niche, plays a crucial role in regulating stem cell self-renewal and differentiation. However, current biological techniques lack the means to recapitulate the complexity of this microenvironment. Nano- and microengineered materials offer innovative methods to: (1) deconstruct the stem cell niche to understand the effects of individual elements; (2) construct complex tissue-like structures resembling the niche to better predict and control cellular processes; and (3) transplant stem cells or activate endogenous stem cell populations for regeneration of aged or diseased tissues. Here, we highlight some of the latest advances in this field and discuss future applications and directions of the use of nano- and microtechnologies for stem cell engineering. PMID:22101755

Engineering approaches toward deconstructing and controlling the stem cell environment.

PubMed

Edalat, Faramarz; Bae, Hojae; Manoucheri, Sam; Cha, Jae Min; Khademhosseini, Ali

2012-06-01

Stem cell-based therapeutics have become a vital component in tissue engineering and regenerative medicine. The microenvironment within which stem cells reside, i.e., the niche, plays a crucial role in regulating stem cell self-renewal and differentiation. However, current biological techniques lack the means to recapitulate the complexity of this microenvironment. Nano- and microengineered materials offer innovative methods to (1) deconstruct the stem cell niche to understand the effects of individual elements; (2) construct complex tissue-like structures resembling the niche to better predict and control cellular processes; and (3) transplant stem cells or activate endogenous stem cell populations for regeneration of aged or diseased tissues. In this article, we highlight some of the latest advances in this field and discuss future applications and directions of the use of nano- and microtechnologies for stem cell engineering.

Therapeutic microparticles functionalized with biomimetic cardiac stem cell membranes and secretome

PubMed Central

Tang, Junnan; Shen, Deliang; Caranasos, Thomas George; Wang, Zegen; Vandergriff, Adam C.; Allen, Tyler A.; Hensley, Michael Taylor; Dinh, Phuong-Uyen; Cores, Jhon; Li, Tao-Sheng; Zhang, Jinying; Kan, Quancheng; Cheng, Ke

2017-01-01

Stem cell therapy represents a promising strategy in regenerative medicine. However, cells need to be carefully preserved and processed before usage. In addition, cell transplantation carries immunogenicity and/or tumourigenicity risks. Mounting lines of evidence indicate that stem cells exert their beneficial effects mainly through secretion (of regenerative factors) and membrane-based cell–cell interaction with the injured cells. Here, we fabricate a synthetic cell-mimicking microparticle (CMMP) that recapitulates stem cell functions in tissue repair. CMMPs carry similar secreted proteins and membranes as genuine cardiac stem cells do. In a mouse model of myocardial infarction, injection of CMMPs leads to the preservation of viable myocardium and augmentation of cardiac functions similar to cardiac stem cell therapy. CMMPs (derived from human cells) do not stimulate T-cell infiltration in immuno-competent mice. In conclusion, CMMPs act as ‘synthetic stem cells’ which mimic the paracrine and biointerfacing activities of natural stem cells in therapeutic cardiac regeneration. PMID:28045024

Cell motion predicts human epidermal stemness

PubMed Central

Toki, Fujio; Tate, Sota; Imai, Matome; Matsushita, Natsuki; Shiraishi, Ken; Sayama, Koji; Toki, Hiroshi; Higashiyama, Shigeki

2015-01-01

Image-based identification of cultured stem cells and noninvasive evaluation of their proliferative capacity advance cell therapy and stem cell research. Here we demonstrate that human keratinocyte stem cells can be identified in situ by analyzing cell motion during their cultivation. Modeling experiments suggested that the clonal type of cultured human clonogenic keratinocytes can be efficiently determined by analysis of early cell movement. Image analysis experiments demonstrated that keratinocyte stem cells indeed display a unique rotational movement that can be identified as early as the two-cell stage colony. We also demonstrate that α6 integrin is required for both rotational and collective cell motion. Our experiments provide, for the first time, strong evidence that cell motion and epidermal stemness are linked. We conclude that early identification of human keratinocyte stem cells by image analysis of cell movement is a valid parameter for quality control of cultured keratinocytes for transplantation. PMID:25897083

Stem Cells Transplantation in the Treatment of Patients with Liver Failure.

PubMed

Tao, Ya-Chao; Wang, Meng-Lan; Chen, En-Qiang; Tang, Hong

2018-02-23

Liver failure is a life-threatening liver disease encompassing severe acute deterioration of liver function. Emergency liver transplantation is the only curative treatment for liver failure, but is restricted by the severe shortage of organ donors. Stem cell, including embroyonic stem cells, induced pluripotent stem cells, mesenchymal stem cells, hematopoietic stem cells and hepatic progenitor cells, have capacity to proliferate and differentiate and could be used in a variety of liver diseases including hereditary liver diseases, cirrhosis and liver failure. We summarized the basic experimental and clinical advances of stem cell transplantation in liver failure treatment, and also discussed the advantages and disadvantage of different stem cells subtype in this field, aiming to provide a perspective on the stem cell-based therapy for liver failure. Stem cells, especially mesenchymal stem cells (mainly low immunogenicity and paracrine characteristics) and induced pluripotent stem cells (generation of desired cell type from somatic cell), are feasible candidates for cell therapy in the treatment of liver failure, but there are some drawbacks remaining to be resolved, such as low engraftment, cryotpreservation methods and tumorigenesis. Stem cell transplantation is a promising but challenging strategy and paves a new way for curing liver failure. But more efforts need to be made to overcome problems before this new strategy could be safely and effectively applied to humans. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Dental pulp stem cells in regenerative dentistry.

PubMed

Casagrande, Luciano; Cordeiro, Mabel M; Nör, Silvia A; Nör, Jacques E

2011-01-01

Stem cells constitute the source of differentiated cells for the generation of tissues during development, and for regeneration of tissues that are diseased or injured postnatally. In recent years, stem cell research has grown exponentially owing to the recognition that stem cell-based therapies have the potential to improve the life of patients with conditions that span from Alzheimer's disease to cardiac ischemia to bone or tooth loss. Growing evidence demonstrates that stem cells are primarily found in niches and that certain tissues contain more stem cells than others. Among these tissues, the dental pulp is considered a rich source of mesenchymal stem cells that are suitable for tissue engineering applications. It is known that dental pulp stem cells have the potential to differentiate into several cell types, including odontoblasts, neural progenitors, osteoblasts, chondrocytes, and adipocytes. The dental pulp stem cells are highly proliferative. This characteristic facilitates ex vivo expansion and enhances the translational potential of these cells. Notably, the dental pulp is arguably the most accessible source of postnatal stem cells. Collectively, the multipotency, high proliferation rates, and accessibility make the dental pulp an attractive source of mesenchymal stem cells for tissue regeneration. This review discusses fundamental concepts of stem cell biology and tissue engineering within the context of regenerative dentistry.

Translating stem cell therapies: the role of companion animals in regenerative medicine

PubMed Central

Volk, Susan W.; Theoret, Christine

2013-01-01

Veterinarians and veterinary medicine have been integral to the development of stem cell therapies. The contributions of large animal experimental models to the development and refinement of modern hematopoietic stem cell transplantation were noted nearly five decades ago. More recent advances in adult stem cell/regenerative cell therapies continue to expand knowledge of the basic biology and clinical applications of stem cells. A relatively liberal legal and ethical regulation of stem cell research in veterinary medicine has facilitated the development and in some instances clinical translation of a variety of cell-based therapies involving hematopoietic (HSC) and mesenchymal stem cells (MSC) as well as other adult regenerative cells and recently embryonic stem cells (ESC) and induced pluripotent stem cells (iPSC). In fact, many of the pioneering developments in these fields of stem cell research have been achieved through collaborations of veterinary and human scientists. This review aims to provide an overview of the contribution of large animal veterinary models in advancing stem cell therapies for both human and clinical veterinary applications. Moreover, in the context of the “One Health Initiative”, the role veterinary patients may play in the future evolution of stem cell therapies for both human and animal patients will be explored. PMID:23627495

Stem cell therapy for ischemic heart diseases.

PubMed

Yu, Hong; Lu, Kai; Zhu, Jinyun; Wang, Jian'an

2017-01-01

Ischemic heart diseases, especially the myocardial infarction, is a major hazard problem to human health. Despite substantial advances in control of risk factors and therapies with drugs and interventions including bypass surgery and stent placement, the ischemic heart diseases usually result in heart failure (HF), which could aggravate social burden and increase the mortality rate. The current therapeutic methods to treat HF stay at delaying the disease progression without repair and regeneration of the damaged myocardium. While heart transplantation is the only effective therapy for end-stage patients, limited supply of donor heart makes it impossible to meet the substantial demand from patients with HF. Stem cell-based transplantation is one of the most promising treatment for the damaged myocardial tissue. Key recent published literatures and ClinicalTrials.gov. Stem cell-based therapy is a promising strategy for the damaged myocardial tissue. Different kinds of stem cells have their advantages for treatment of Ischemic heart diseases. The efficacy and potency of cell therapies vary significantly from trial to trial; some clinical trials did not show benefit. Diverged effects of cell therapy could be affected by cell types, sources, delivery methods, dose and their mechanisms by which delivered cells exert their effects. Understanding the origin of the regenerated cardiomyocytes, exploring the therapeutic effects of stem cell-derived exosomes and using the cell reprogram technology to improve the efficacy of cell therapy for cardiovascular diseases. Recently, stem cell-derived exosomes emerge as a critical player in paracrine mechanism of stem cell-based therapy. It is promising to exploit exosomes-based cell-free therapy for ischemic heart diseases in the future. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

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.

Stem cells and corneal epithelial maintenance – insights from the mouse and other animal models

PubMed Central

Mort, Richard L.; Douvaras, Panagiotis; Morley, Steven D.; Dorà, Natalie; Hill, Robert E.; Collinson, J. Martin; West, John D.

2012-01-01

Maintenance of the corneal epithelium is essential for vision and is a dynamic process incorporating constant cell production, movement and loss. Although cell based therapies involving the transplantation of putative stem cells are well advanced for the treatment of human corneal defects, the scientific understanding of these interventions is poor. No definitive marker that discriminates stem cells that maintain the corneal epithelium from the surrounding tissue has been discovered and the identity of these elusive cells is, therefore, hotly debated. The key elements of corneal epithelial maintenance have long been recognised but it is still not known how this dynamic balance is coordinated during normal homeostasis to ensure the corneal epithelium is maintained at a uniform thickness. Most indirect experimental evidence supports the limbal epithelial stem cell (LESC) hypothesis, which proposes that the adult corneal epithelium is maintained by stem cells located in the limbus at the corneal periphery. However, this has been challenged recently by the corneal epithelial stem cell (CESC) hypothesis, which proposes that during normal homeostasis the mouse corneal epithelium is maintained by stem cells located throughout the basal corneal epithelium with LESCs only contributing during wound healing. In this chapter we review experimental studies, mostly based on animal work, that provide insights into how stem cells maintain the normal corneal epithelium and consider the merits of the alternative LESC and CESC hypotheses. Finally, we highlight some recent research on other stem cell systems and consider how this could influence future research directions for identifying the stem cells that maintain the corneal epithelium. PMID:22918816

Ethical and Safety Issues of Stem Cell-Based Therapy.

PubMed

Volarevic, Vladislav; Markovic, Bojana Simovic; Gazdic, Marina; Volarevic, Ana; Jovicic, Nemanja; Arsenijevic, Nebojsa; Armstrong, Lyle; Djonov, Valentin; Lako, Majlinda; Stojkovic, Miodrag

2018-01-01

Results obtained from completed and on-going clinical studies indicate huge therapeutic potential of stem cell-based therapy in the treatment of degenerative, autoimmune and genetic disorders. However, clinical application of stem cells raises numerous ethical and safety concerns. In this review, we provide an overview of the most important ethical issues in stem cell therapy, as a contribution to the controversial debate about their clinical usage in regenerative and transplantation medicine. We describe ethical challenges regarding human embryonic stem cell (hESC) research, emphasizing that ethical dilemma involving the destruction of a human embryo is a major factor that may have limited the development of hESC-based clinical therapies. With previous derivation of induced pluripotent stem cells (iPSCs) this problem has been overcome, however current perspectives regarding clinical translation of iPSCs still remain. Unlimited differentiation potential of iPSCs which can be used in human reproductive cloning, as a risk for generation of genetically engineered human embryos and human-animal chimeras, is major ethical issue, while undesired differentiation and malignant transformation are major safety issues. Although clinical application of mesenchymal stem cells (MSCs) has shown beneficial effects in the therapy of autoimmune and chronic inflammatory diseases, the ability to promote tumor growth and metastasis and overestimated therapeutic potential of MSCs still provide concerns for the field of regenerative medicine. This review offers stem cell scientists, clinicians and patient's useful information and could be used as a starting point for more in-depth analysis of ethical and safety issues related to clinical application of stem cells.

Ethical and Safety Issues of Stem Cell-Based Therapy

PubMed Central

Volarevic, Vladislav; Markovic, Bojana Simovic; Gazdic, Marina; Volarevic, Ana; Jovicic, Nemanja; Arsenijevic, Nebojsa; Armstrong, Lyle; Djonov, Valentin; Lako, Majlinda; Stojkovic, Miodrag

2018-01-01

Results obtained from completed and on-going clinical studies indicate huge therapeutic potential of stem cell-based therapy in the treatment of degenerative, autoimmune and genetic disorders. However, clinical application of stem cells raises numerous ethical and safety concerns. In this review, we provide an overview of the most important ethical issues in stem cell therapy, as a contribution to the controversial debate about their clinical usage in regenerative and transplantation medicine. We describe ethical challenges regarding human embryonic stem cell (hESC) research, emphasizing that ethical dilemma involving the destruction of a human embryo is a major factor that may have limited the development of hESC-based clinical therapies. With previous derivation of induced pluripotent stem cells (iPSCs) this problem has been overcome, however current perspectives regarding clinical translation of iPSCs still remain. Unlimited differentiation potential of iPSCs which can be used in human reproductive cloning, as a risk for generation of genetically engineered human embryos and human-animal chimeras, is major ethical issue, while undesired differentiation and malignant transformation are major safety issues. Although clinical application of mesenchymal stem cells (MSCs) has shown beneficial effects in the therapy of autoimmune and chronic inflammatory diseases, the ability to promote tumor growth and metastasis and overestimated therapeutic potential of MSCs still provide concerns for the field of regenerative medicine. This review offers stem cell scientists, clinicians and patient's useful information and could be used as a starting point for more in-depth analysis of ethical and safety issues related to clinical application of stem cells. PMID:29333086

Making it stick: chasing the optimal stem cells for cardiac regeneration

PubMed Central

Quijada, Pearl; Sussman, Mark A

2014-01-01

Despite the increasing use of stem cells for regenerative-based cardiac therapy, the optimal stem cell population(s) remains in a cloud of uncertainty. In the past decade, the field has witnessed a surge of researchers discovering stem cell populations reported to directly and/or indirectly contribute to cardiac regeneration through processes of cardiomyogenic commitment and/or release of cardioprotective paracrine factors. This review centers upon defining basic biological characteristics of stem cells used for sustaining cardiac integrity during disease and maintenance of communication between the cardiac environment and stem cells. Given the limited successes achieved so far in regenerative therapy, the future requires development of unprecedented concepts involving combinatorial approaches to create and deliver the optimal stem cell(s) that will enhance myocardial healing. PMID:25340282

Cell Therapy From Bench to Bedside Translation in CNS Neurorestoratology Era

PubMed Central

Huang, Hongyun; Chen, Lin; Sanberg, Paul

2010-01-01

Recent advances in cell biology, neural injury and repair, and the progress towards development of neurorestorative interventions are the basis for increased optimism. Based on the complexity of the processes of demyelination and remyelination, degeneration and regeneration, damage and repair, functional loss and recovery, it would be expected that effective therapeutic approaches will require a combination of strategies encompassing neuroplasticity, immunomodulation, neuroprotection, neurorepair, neuroreplacement, and neuromodulation. Cell-based restorative treatment has become a new trend, and increasing data worldwide have strongly proven that it has a pivotal therapeutic value in CNS disease. Moreover, functional neurorestoration has been achieved to a certain extent in the CNS clinically. Up to now, the cells successfully used in preclinical experiments and/or clinical trial/treatment include fetal/embryonic brain and spinal cord tissue, stem cells (embryonic stem cells, neural stem/progenitor cells, hematopoietic stem cells, adipose-derived adult stem/precursor cells, skin-derived precursor, induced pluripotent stem cells), glial cells (Schwann cells, oligodendrocyte, olfactory ensheathing cells, astrocytes, microglia, tanycytes), neuronal cells (various phenotypic neurons and Purkinje cells), mesenchymal stromal cells originating from bone marrow, umbilical cord, and umbilical cord blood, epithelial cells derived from the layer of retina and amnion, menstrual blood-derived stem cells, Sertoli cells, and active macrophages, etc. Proof-of-concept indicates that we have now entered a new era in neurorestoratology. PMID:21359168

Characterization of Human Mammary Epithelial Stem Cells

DTIC Science & Technology

2010-10-01

This term reflects the method used to detect murine mammary stem cells which is based on their individual ability to regenerate an entire mammary tree......mammary stem cells. We now describe a method for detecting an analogous subpopulation in normal human mammary tissue. Dissociated cells are suspended

Future research and therapeutic applications of human stem cells: general, regulatory, and bioethical aspects.

PubMed

Liras, Antonio

2010-12-10

There is much to be investigated about the specific characteristics of stem cells and about the efficacy and safety of the new drugs based on this type of cells, both embryonic as adult stem cells, for several therapeutic indications (cardiovascular and ischemic diseases, diabetes, hematopoietic diseases, liver diseases). Along with recent progress in transference of nuclei from human somatic cells, as well as iPSC technology, has allowed availability of lineages of all three germ layers genetically identical to those of the donor patient, which permits safe transplantation of organ-tissue-specific adult stem cells with no immune rejection. The main objective is the need for expansion of stem cell characteristics to maximize stem cell efficacy (i.e. the proper selection of a stem cell) and the efficacy (maximum effect) and safety of stem cell derived drugs. Other considerations to take into account in cell therapy will be the suitability of infrastructure and technical staff, biomaterials, production costs, biobanks, biosecurity, and the biotechnological industry. The general objectives in the area of stem cell research in the next few years, are related to identification of therapeutic targets and potential therapeutic tests, studies of cell differentiation and physiological mechanisms, culture conditions of pluripotent stem cells and efficacy and safety tests for stem cell-based drugs or procedures to be performed in both animal and human models in the corresponding clinical trials. A regulatory framework will be required to ensure patient accessibility to products and governmental assistance for their regulation and control. Bioethical aspects will be required related to the scientific and therapeutic relevance and cost of cryopreservation over time, but specially with respect to embryos which may ultimately be used for scientific uses of research as source of embryonic stem cells, in which case the bioethical conflict may be further aggravated.

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.

Parsing Stem Cell Lineage Development Using High Content Image Analysis of Epigenetic Spatial Markers.

PubMed

Kim, Joseph J; Moghe, Prabhas V

2018-06-14

This unit describes a protocol for acquiring and analyzing high-content super-resolution images of human stem cell nuclei for the characterization and classification of the cell differentiation paths based on distinct patterns of epigenetic mark organization. Here, we describe the cell culture, immunocytochemical labeling, super-resolution imaging parameters, and MATLAB-based quantitative image analysis approaches for monitoring human mesenchymal stem cells (hMSCs) and human induced pluripotent stem cells (hiPSCs) as the cells differentiate towards various lineages. Although this protocol uses specific cell types as examples, this approach could be easily extended to a variety of cell types and nuclear epigenetic and mechanosensitive biomarkers that are relevant to specific cell developmental scenarios. © 2018 by John Wiley & Sons, Inc. Copyright © 2018 John Wiley & Sons, Inc.

Novel Surface-Enhanced Raman Scattering-based Assays for Ultra-sensitive Detection of Human Pluripotent Stem Cells

PubMed Central

Han, Jingjia; Qian, Ximei; Wu, Qingling; Jha, Rajneesh; Duan, Jinshuai; Yang, Zhou; Maher, Kevin O.; Nie, Shuming; Xu, Chunhui

2017-01-01

Human pluripotent stem cells (hPSCs) are a promising cell source for regenerative medicine, but their derivatives need to be rigorously evaluated for residual stem cells to prevent teratoma formation. Here, we report the development of novel surface-enhanced Raman scattering (SERS)-based assays that can detect trace numbers of undifferentiated hPSCs in mixed cell populations in a highly specific, ultra-sensitive, and time-efficient manner. By targeting stem cell surface markers SSEA-5 and TRA-1-60 individually or simultaneously, these SERS assays were able to identify as few as 1 stem cell in 106 cells, a sensitivity (0.0001%) which was ~2,000 to 15,000-fold higher than that of flow cytometry assays. Using the SERS assay, we demonstrate that the aggregation of hPSC-based cardiomyocyte differentiation cultures into 3D spheres significantly reduced SSEA-5+ and TRA-1-60+ cells compared with parallel 2D cultures. Thus, SERS may provide a powerful new technology for quality control of hPSC-derived products for preclinical and clinical applications. PMID:27509304

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.

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

PubMed Central

O’Brien, Lucy Erin; Bilder, David

2014-01-01

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

[Clinical significance of autologous transplantation with hematopoietic stem cells in leukemia and solid tumors].

PubMed

Hinterberger, W; Adler, V; Bauer, K; Haberhauer, G; Habertheuer, K H; Höniger, S; Huber, K; Kier, P; Kittel, E; Ruckser, R

1995-01-01

Autologous Transplantation of hematopoietic tissue with frozen hematopoietic stem cells is increasingly used for leukemias and lymphomas, but also for some solid tumors. In the past, autotransplants have been performed with bone marrow as the source of hematopoietic stem cells. Circulating, blood derived hematopoietic stem cells, however, allow safe engraftment of all cell lines after supralethal chemo-radiotherapy. This survey describes the role of autologous stem cell transplantation in disorders that are currently in the center of clinical and scientific interest. This estimation is based on the proportion of protocols dealing with, and centering on, autologous stem cell transplantation in the context of treatment for leukemias and solid tumors ("Oncodisc", "PDQ").

Stem cell-based tissue-engineering for treatment of meniscal tears in the avascular zone.

PubMed

Zellner, Johannes; Hierl, Katja; Mueller, Michael; Pfeifer, Christian; Berner, Arne; Dienstknecht, Thomas; Krutsch, Werner; Geis, Sebastian; Gehmert, Sebastian; Kujat, Richard; Dendorfer, Sebastian; Prantl, Lukas; Nerlich, Michael; Angele, Peter

2013-10-01

Meniscal tears in the avascular zone have a poor self-healing potential, however partial meniscectomy predisposes the knee for early osteoarthritis. Tissue engineering with mesenchymal stem cells and a hyaluronan collagen based scaffold is a promising approach to repair meniscal tears in the avascular zone. 4 mm longitudinal meniscal tears in the avascular zone of lateral menisci of New Zealand White Rabbits were performed. The defect was left empty, sutured with a 5-0 suture or filled with a hyaluronan/collagen composite matrix without cells, with platelet rich plasma or with autologous mesenchymal stem cells. Matrices with stem cells were in part precultured in chondrogenic medium for 14 days prior to the implantation. Menisci were harvested at 6 and 12 weeks. The developed repair tissue was analyzed macroscopically, histologically and biomechanically. Untreated defects, defects treated with suture alone, with cell-free or with platelet rich plasma seeded implants showed a muted fibrous healing response. The implantation of stem cell-matrix constructs initiated fibrocartilage-like repair tissue, with better integration and biomechanical properties in the precultured stem cell-matrix group. A hyaluronan-collagen based composite scaffold seeded with mesenchymal stem cells is more effective in the repair avascular meniscal tear with stable meniscus-like tissue and to restore the native meniscus. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.

Identifying Stem-like Cells Using Mitochondrial Membrane Potential | Center for Cancer Research

Cancer.gov

Therapies that are based on living cells promise to improve treatments for metastatic cancer and for many degenerative diseases. Lasting treatment of these maladies may require the durable persistence of cells. Long-term engraftment of cells – for months or years – and the generation of large numbers of progeny are characteristics of stem cells. Most approaches to isolate viable hematopoetic stem cells and therapeutically active T cells are based on immunophenotyping using highly multicolored flow cytometry. However, these methods do not directly measure the metabolic features of cells, which are known to be important in predicting cell fate.

Stem cell-based biological tooth repair and regeneration

PubMed Central

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

2010-01-01

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

The role of stem cells in aesthetic surgery: fact or fiction?

PubMed

McArdle, Adrian; Senarath-Yapa, Kshemendra; Walmsley, Graham G; Hu, Michael; Atashroo, David A; Tevlin, Ruth; Zielins, Elizabeth; Gurtner, Geoffrey C; Wan, Derrick C; Longaker, Michael T

2014-08-01

Stem cells are attractive candidates for the development of novel therapies, targeting indications that involve functional restoration of defective tissue. Although most stem cell therapies are new and highly experimental, there are clinics around the world that exploit vulnerable patients with the hope of offering supposed stem cell therapies, many of which operate without credible scientific merit, oversight, or other patient protection. The authors review the potential and the drawbacks of incorporation of stem cells in cosmetic procedures. A review of U.S. Food and Drug Administration-approved indications and ongoing clinical trials with adipose stem cells is provided. Furthermore, a "snapshot" analysis of Web sites using the search terms "stem cell therapy" or "stem cell treatment" or "stem cell facelift" was performed. Despite the protective net cast by regulatory agencies such as the U.S. Food and Drug Administration and professional societies such as the American Society of Plastic Surgeons, the authors are witnessing worrying advertisements for procedures such as stem cell face lifts, stem cell breast augmentations, and even stem cell vaginal rejuvenation. The marketing and promotion of stem cell procedures in aesthetic surgery is not adequately supported by clinical evidence in the majority of cases. Stem cells offer tremendous potential, but the marketplace is saturated with unsubstantiated and sometimes fraudulent claims that may place patients at risk. With plastic surgeons at the forefront of stem cell-based regenerative medicine, it is critically important that they provide an example of a rigorous approach to research, data collection, and advertising of stem cell therapies.

Linking stem cell function and growth pattern of intestinal organoids.

PubMed

Thalheim, Torsten; Quaas, Marianne; Herberg, Maria; Braumann, Ulf-Dietrich; Kerner, Christiane; Loeffler, Markus; Aust, Gabriela; Galle, Joerg

2018-01-15

Intestinal stem cells (ISCs) require well-defined signals from their environment in order to carry out their specific functions. Most of these signals are provided by neighboring cells that form a stem cell niche, whose shape and cellular composition self-organize. Major features of this self-organization can be studied in ISC-derived organoid culture. In this system, manipulation of essential pathways of stem cell maintenance and differentiation results in well-described growth phenotypes. We here provide an individual cell-based model of intestinal organoids that enables a mechanistic explanation of the observed growth phenotypes. In simulation studies of the 3D structure of expanding organoids, we investigate interdependences between Wnt- and Notch-signaling which control the shape of the stem cell niche and, thus, the growth pattern of the organoids. Similar to in vitro experiments, changes of pathway activities alter the cellular composition of the organoids and, thereby, affect their shape. Exogenous Wnt enforces transitions from branched into a cyst-like growth pattern; known to occur spontaneously during long term organoid expansion. Based on our simulation results, we predict that the cyst-like pattern is associated with biomechanical changes of the cells which assign them a growth advantage. The results suggest ongoing stem cell adaptation to in vitro conditions during long term expansion by stabilizing Wnt-activity. Our study exemplifies the potential of individual cell-based modeling in unraveling links between molecular stem cell regulation and 3D growth of tissues. This kind of modeling combines experimental results in the fields of stem cell biology and cell biomechanics constituting a prerequisite for a better understanding of tissue regeneration as well as developmental processes. Copyright © 2017 Elsevier Inc. All rights reserved.

Thermogelling 3D Systems towards Stem Cell-Based Tissue Regeneration Therapies.

PubMed

Wang, Xiaoyuan; Young, David James; Wu, Yun-Long; Loh, Xian Jun

2018-03-02

Stem cell culturing and differentiation is a very important research direction for tissue engineering. Thermogels are well suited for encapsulating cells because of their non-biotoxic nature and mild sol-gel transition as temperature increases. In particular, thermogels provide a 3D growth environment for stem cell growth, which is more similar to the extracellular matrix than flat substrates, so thermogels as a medium can overcome many of the cell abnormalities caused by 2D cell growth. In this review, we summarize the applications of thermogels in cell and stem cell culture in recent years. We also elaborate on the methods to induce stem cell differentiation by using thermogel-based 3D scaffolds. In particular, thermogels, encapsulating specific differentiation-inducing factor and having specific structures and moduli, can induce the differentiation into the desired tissue cells. Three dimensional thermogel scaffolds that control the growth and differentiation of cells will undoubtedly have a bright future in regenerative medicine.

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

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

[Ethical aspects of human embryonic stem cell use and commercial umbilical cord blood stem cell banking. Ethical reflections on the occasion of the regulation of the European Council and Parliament on advanced therapy medicinal products].

PubMed

Virt, G

2010-01-01

The regulation of the European Council and Parliament on advanced therapy medicinal products also includes therapies with human embryonic stem cells. The use of these stem cells is controversially and heavily discussed. Contrary to the use of adult stem cells, medical and ethical problems concerning the use of human embryonic stem cells persists, because this use is based on the destruction of human life at the very beginning. The regulation foresees, therefore, subsidiarity within the European Member States. Although there are no ethical problems in principle with the use of stem cells from the umbilical cord blood, there are social ethical doubts with the banking of these stem cells for autologous use without any currently foreseeable medical advantage by commercial blood banks. Also in this case subsidiarity is valid.

Accelerating glioblastoma drug discovery: Convergence of patient-derived models, genome editing and phenotypic screening.

PubMed

O'Duibhir, Eoghan; Carragher, Neil O; Pollard, Steven M

2017-04-01

Patients diagnosed with glioblastoma (GBM) continue to face a bleak prognosis. It is critical that new effective therapeutic strategies are developed. GBM stem cells have molecular hallmarks of neural stem and progenitor cells and it is possible to propagate both non-transformed normal neural stem cells and GBM stem cells, in defined, feeder-free, adherent culture. These primary stem cell lines provide an experimental model that is ideally suited to cell-based drug discovery or genetic screens in order to identify tumour-specific vulnerabilities. For many solid tumours, including GBM, the genetic disruptions that drive tumour initiation and growth have now been catalogued. CRISPR/Cas-based genome editing technologies have recently emerged, transforming our ability to functionally annotate the human genome. Genome editing opens prospects for engineering precise genetic changes in normal and GBM-derived neural stem cells, which will provide more defined and reliable genetic models, with critical matched pairs of isogenic cell lines. Generation of more complex alleles such as knock in tags or fluorescent reporters is also now possible. These new cellular models can be deployed in cell-based phenotypic drug discovery (PDD). Here we discuss the convergence of these advanced technologies (iPS cells, neural stem cell culture, genome editing and high content phenotypic screening) and how they herald a new era in human cellular genetics that should have a major impact in accelerating glioblastoma drug discovery. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

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

Application of Stem Cell Technology in Dental Regenerative Medicine.

PubMed

Feng, Ruoxue; Lengner, Chistopher

2013-07-01

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

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

Comparative Chondrogenesis of Human Cell Sources in 3D Scaffolds

PubMed Central

Tıg̑lı, R. Seda; Ghosh, Sourabh; Laha, Michael M.; Shevde, Nirupama K.; Daheron, Laurence; Gimble, Jeffrey; Gümüşdereliog̑lu, Menemşe; Kaplan, David L.

2009-01-01

Cartilage tissue can be engineered by starting from a diversity of cell sources, including stem-cell based and primary cell-based platforms. Selecting an appropriate cell source for the process of cartilage tissue engineering or repair is critical and challenging due to the variety of cell options available. In this study, cellular responses of isolated human chondrocytes, human embryonic stem cells and mesenchymal stem cells (MSCs) derived from three sources, human embryonic stem cells, bone marrow and adipose tissue, were assessed for chondrogenic potential in 3D culture. All cell sources were characterized by FACS analysis to compare expression of some surface markers. The cells were differentiated in two different biomaterial matrices, silk and chitosan scaffolds, in the presence and absence of bone morphogenetic protein 6 (BMP-6) along with the standard chondrogenic differentiating factors. Embryonic stem cells derived MSCs showed unique characteristics with preserved chondrogenic phenotype in both scaffolds with regard to chondrogenesis, as determined by real time RT-PCR, histological and microscopic analyses. After 4 weeks of cultivation, embryonic stem cells derived MSCs were promising for chondrogenesis, particularly in the silk scaffolds with BMP-6. The results suggest that cell source differences are important to consider with regard to chondrogenic outcomes and with the variables addressed here, the human embryonic stem cells derived MSCs were the preferred cell source. PMID:19382119

Progress and Prospects for Stem Cell Engineering

PubMed Central

Ashton, Randolph S.; Keung, Albert J.; Peltier, Joseph; Schaffer, David V.

2018-01-01

Stem cells offer tremendous biomedical potential owing to their abilities to self-renew and differentiate into cell types of multiple adult tissues. Researchers and engineers have increasingly developed novel discovery technologies, theoretical approaches, and cell culture systems to investigate microenvironmental cues and cellular signaling events that control stem cell fate. Many of these technologies facilitate high-throughput investigation of microenvironmental signals and the intracellular signaling networks and machinery processing those signals into cell fate decisions. As our aggregate empirical knowledge of stem cell regulation grows, theoretical modeling with systems and computational biology methods has and will continue to be important for developing our ability to analyze and extract important conceptual features of stem cell regulation from complex data. Based on this body of knowledge, stem cell engineers will continue to develop technologies that predictably control stem cell fate with the ultimate goal of being able to accurately and economically scale up these systems for clinical-grade production of stem cell therapeutics. PMID:22432628

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.

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

PubMed

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

2017-04-01

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

Stem cell-associated genes are extremely poor prognostic factors for soft-tissue sarcoma patients.

PubMed

Taubert, H; Würl, P; Greither, T; Kappler, M; Bache, M; Bartel, F; Kehlen, A; Lautenschläger, C; Harris, L C; Kaushal, D; Füssel, S; Meye, A; Böhnke, A; Schmidt, H; Holzhausen, H-J; Hauptmann, S

2007-11-01

Cancer stem cells can play an important role in tumorigenesis and tumor progression. However, it is still difficult to detect and isolate cancer stem cells. An alternative approach is to analyse stem cell-associated gene expression. We investigated the coexpression of three stem cell-associated genes, Hiwi, hTERT and survivin, by quantitative real-time-PCR in 104 primary soft-tissue sarcomas (STS). Multivariate Cox's proportional hazards regression analyses allowed correlating gene expression with overall survival for STS patients. Coexpression of all three stem cell-associated genes resulted in a significantly increased risk of tumor-related death. Importantly, tumors of patients with the poorest prognosis were of all four tumor stages, suggesting that their risk is based upon coexpression of stem cell-associated genes rather than on tumor stage.

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

PubMed

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

2017-10-01

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

1,5-Disubstituted benzimidazoles that direct cardiomyocyte differentiation from mouse embryonic stem cells.

PubMed

Okolotowicz, Karl J; Bushway, Paul; Lanier, Marion; Gilley, Cynthia; Mercola, Mark; Cashman, John R

2015-09-01

Cardiomyopathy is the leading cause of death worldwide. Despite progress in medical treatments, heart transplantation is one of the only current options for those with infarcted heart muscle. Stem cell differentiation technology may afford cell-based therapeutics that may lead to the generation of new, healthy heart muscle cells from undifferentiated stem cells. Our approach is to use small molecules to stimulate stem cell differentiation. Herein, we describe a novel class of 1,5-disubstituted benzimidazoles that induce differentiation of stem cells into cardiac cells. We report on the evaluation in vitro for cardiomyocyte differentiation and describe structure-activity relationship results that led to molecules with drug-like properties. The results of this study show the promise of small molecules to direct stem cell lineage commitment, to probe signaling pathways and to develop compounds for the stimulation of stem cells to repair damaged heart tissue. Copyright © 2015 Elsevier Ltd. All rights reserved.

1,5-Disubstituted benzimidazoles that direct cardiomyocyte differentiation from mouse embryonic stem cells

PubMed Central

Okolotowicz, Karl J.; Bushway, Paul; Lanier, Marion; Gilley, Cynthia; Cynthia, Mark; Cashman, John R.

2016-01-01

Cardiomyopathy is the leading cause of death worldwide. Despite progress in medical treatments, heart transplantation is one of the only current options for those with infarcted heart muscle. Stem cell differentiation technology may afford cell-based therapeutics that may lead to the generation of new, healthy heart muscle cells from undifferentiated stem cells. Our approach is to use small molecules to stimulate stem cell differentiation. Herein, we describe a novel class of 1,5-disubstituted benzimidazoles that induce differentiation of stem cells into cardiac cells. We report on the evaluation in vitro for cardiomyocyte differentiation and describe structure–activity relationship results that led to molecules with drug-like properties. The results of this study show the promise of small molecules to direct stem cell lineage commitment, to probe signaling pathways and to develop compounds for the stimulation of stem cells to repair damaged heart tissue. PMID:26278027

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.

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

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

PubMed Central

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

2016-01-01

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

Therapeutic Application of Pluripotent Stem Cells: Challenges and Risks.

PubMed

Martin, Ulrich

2017-01-01

Stem-cell-based therapies are considered to be promising and innovative but complex approaches. Induced pluripotent stem cells (iPSCs) combine the advantages of adult stem cells with the hitherto unique characteristics of embryonic stem cells (ESCs). Major progress has already been achieved with regard to reprogramming technology, but also regarding targeted genome editing and scalable expansion and differentiation of iPSCs and ESCs, in some cases yielding highly enriched preparations of well-defined cell lineages at clinically required dimensions. It is noteworthy, however, that for many applications critical requirements such as the targeted specification into distinct cellular subpopulations and a proper cell maturation remain to be achieved. Moreover, current hurdles such as low survival rates and insufficient functional integration of cellular transplants remain to be overcome. Nevertheless, PSC technologies obviously have come of age and matured to a stage where various clinical applications of PSC-based cellular therapies have been initiated and are conducted.

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

PubMed

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

2016-02-01

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

[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.

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

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.

Stem-Cell-Based Tumorigenesis in Adult Drosophila.

PubMed

Hou, S X; Singh, S R

2017-01-01

Recent studies suggest that a small subset of cells within a tumor, the so-called cancer stem cells (CSCs), are responsible for tumor propagation, relapse, and the eventual death of most cancer patients. CSCs may derive from a few tumor-initiating cells, which are either transformed normal stem cells or reprogrammed differentiated cells after acquiring initial cancer-causing mutations. CSCs and normal stem cells share some properties, but CSCs differ from normal stem cells in their tumorigenic ability. Notably, CSCs are usually resistant to chemo- and radiation therapies. Despite the apparent roles of CSCs in human cancers, the biology underlying their behaviors remains poorly understood. Over the past few years, studies in Drosophila have significantly contributed to this new frontier of cancer research. Here, we first review how stem-cell tumors are initiated and propagated in Drosophila, through niche appropriation in the posterior midgut and through stem-cell competition for niche occupancy in the testis. We then discuss the differences between normal and tumorigenic stem cells, revealed by studying Ras V12 -transformed stem-cell tumors in the Drosophila kidney. Finally, we review the biology behind therapy resistance, which has been elucidated through studies of stem-cell resistance and sensitivity to death inducers using female germline stem cells and intestinal stem cells of the posterior midgut. We expect that screens using adult Drosophila neoplastic stem-cell tumor models will be valuable for identifying novel and effective compounds for treating human cancers. © 2017 Elsevier Inc. All rights reserved.

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.

Concise Review: Conceptualizing Paralogous Stem-Cell Niches and Unfolding Bone Marrow Progenitor Cell Identities.

PubMed

Chen, Kevin G; Johnson, Kory R; McKay, Ronald D G; Robey, Pamela G

2018-01-01

Lineage commitment and differentiation of skeletal stem cells/bone marrow stromal cells (SSCs/BMSCs, often called bone marrow-derived "mesenchymal stem/stromal" cells) offer an important opportunity to study skeletal and hematopoietic diseases, and for tissue engineering and regenerative medicine. Currently, many studies in this field have relied on cell lineage tracing methods in mouse models, which have provided a significant advancement in our knowledge of skeletal and hematopoietic stem-cell niches in bone marrow (BM). However, there is a lack of agreement in numerous fundamental areas, including origins of various BM stem-cell niches, cell identities, and their physiological roles in the BM. In order to resolve these issues, we propose a new hypothesis of "paralogous" stem-cell niches (PSNs); that is, progressively altered parallel niches within an individual species throughout the life span of the organism. A putative PSN code seems to be plausible based on analysis of transcriptional signatures in two representative genes that encode Nes-GFP and leptin receptors, which are frequently used to monitor SSC lineage development in BM. Furthermore, we suggest a dynamic paralogous BM niche (PBMN) model that elucidates the coupling and uncoupling mechanisms between BM stem-cell niches and their zones of active regeneration during different developmental stages. Elucidation of these PBMNs would enable us to resolve the existing controversies, thus paving the way to achieving precision regenerative medicine and pharmaceutical applications based on these BM cell resources. Stem Cells 2018;36:11-21. © 2017 AlphaMed Press.

Stem cell based anti-HIV Gene therapy

PubMed Central

Kitchen, Scott G.; Shimizu, Saki; An, Dong Sung

2011-01-01

Human stem cell-based therapeutic intervention strategies for treating HIV infection have recently undergone a renaissance as a major focus of investigation. Unlike most conventional antiviral therapies, genetically engineered hematopoietic stem cells possess the capacity for prolonged self-renewal that would continuously produce protected immune cells to fight against HIV. A successful strategy therefore has the potential to stably control and ultimately eradicate HIV from patients by a single or minimal treatment. Recent progress in the development of new technologies and clinical trials sets the stage for the current generation of gene therapy approaches to combat HIV infection. In this review, we will discuss two major approaches that are currently underway in the development of stem cell-based gene therapy to target HIV: One that focuses on the protection of cells from productive infection with HIV, and the other that focuses on targeting immune cells to directly combat HIV infection. PMID:21247612

Identification of a novel putative pancreatic stem/progenitor cell marker DCAMKL-1 in normal mouse pancreas.

PubMed

May, Randal; Sureban, Sripathi M; Lightfoot, Stan A; Hoskins, Aimee B; Brackett, Daniel J; Postier, Russell G; Ramanujam, Rama; Rao, Chinthalapally V; Wyche, James H; Anant, Shrikant; Houchen, Courtney W

2010-08-01

Stem cells are critical in maintaining adult homeostasis and have been proposed to be the origin of many solid tumors, including pancreatic cancer. Here we demonstrate the expression patterns of the putative intestinal stem cell marker DCAMKL-1 in the pancreas of uninjured C57BL/6 mice compared with other pancreatic stem/progenitor cell markers. We then determined the viability of isolated pancreatic stem/progenitor cells in isotransplantation assays following DCAMKL-1 antibody-based cell sorting. Sorted cells were grown in suspension culture and injected into the flanks of athymic nude mice. Here we report that DCAMKL-1 is expressed in the main pancreatic duct epithelia and islets, but not within acinar cells. Coexpression was observed with somatostatin, NGN3, and nestin, but not glucagon or insulin. Isolated DCAMKL-1+ cells formed spheroids in suspension culture and induced nodule formation in isotransplantation assays. Analysis of nodules demonstrated markers of early pancreatic development (PDX-1), glandular epithelium (cytokeratin-14 and Ep-CAM), and isletlike structures (somatostatin and secretin). These data taken together suggest that DCAMKL-1 is a novel putative stem/progenitor marker, can be used to isolate normal pancreatic stem/progenitors, and potentially regenerates pancreatic tissues. This may represent a novel tool for regenerative medicine and a target for anti-stem cell-based therapeutics in pancreatic cancer.

Identification of a novel putative pancreatic stem/progenitor cell marker DCAMKL-1 in normal mouse pancreas

PubMed Central

May, Randal; Sureban, Sripathi M.; Lightfoot, Stan A.; Hoskins, Aimee B.; Brackett, Daniel J.; Postier, Russell G.; Ramanujam, Rama; Rao, Chinthalapally V.; Wyche, James H.; Anant, Shrikant

2010-01-01

Stem cells are critical in maintaining adult homeostasis and have been proposed to be the origin of many solid tumors, including pancreatic cancer. Here we demonstrate the expression patterns of the putative intestinal stem cell marker DCAMKL-1 in the pancreas of uninjured C57BL/6 mice compared with other pancreatic stem/progenitor cell markers. We then determined the viability of isolated pancreatic stem/progenitor cells in isotransplantation assays following DCAMKL-1 antibody-based cell sorting. Sorted cells were grown in suspension culture and injected into the flanks of athymic nude mice. Here we report that DCAMKL-1 is expressed in the main pancreatic duct epithelia and islets, but not within acinar cells. Coexpression was observed with somatostatin, NGN3, and nestin, but not glucagon or insulin. Isolated DCAMKL-1+ cells formed spheroids in suspension culture and induced nodule formation in isotransplantation assays. Analysis of nodules demonstrated markers of early pancreatic development (PDX-1), glandular epithelium (cytokeratin-14 and Ep-CAM), and isletlike structures (somatostatin and secretin). These data taken together suggest that DCAMKL-1 is a novel putative stem/progenitor marker, can be used to isolate normal pancreatic stem/progenitors, and potentially regenerates pancreatic tissues. This may represent a novel tool for regenerative medicine and a target for anti-stem cell-based therapeutics in pancreatic cancer. PMID:20522640

Vitamin D is a determinant of mouse intestinal Lgr5 stem cell functions.

PubMed

Peregrina, Karina; Houston, Michele; Daroqui, Cecilia; Dhima, Elena; Sellers, Rani S; Augenlicht, Leonard H

2015-01-01

Lgr5+ intestinal crypt base columnar cells function as stem cells whose progeny populate the villi, and Lgr5+ cells in which Apc is inactivated can give rise to tumors. Surprisingly, these Lgr5+ stem cell properties were abrogated by the lower dietary vitamin D and calcium in a semi-purified diet that promotes both genetically initiated and sporadic intestinal tumors. Inactivation of the vitamin D receptor in Lgr5+ cells established that compromise of Lgr5 stem cell function was a rapid, cell autonomous effect of signaling through the vitamin D receptor. The loss of Lgr5 stem cell function was associated with presence of Ki67 negative Lgr5+ cells at the crypt base. Therefore, vitamin D, a common nutrient and inducer of intestinal cell maturation, is an environmental factor that is a determinant of Lgr5+ stem cell functions in vivo. Since diets used in reports that establish and dissect mouse Lgr5+ stem cell activity likely provided vitamin D levels well above the range documented for human populations, the contribution of Lgr5+ cells to intestinal homeostasis and tumor formation in humans may be significantly more limited, and variable in the population, then suggested by published rodent studies. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Biodegradable Polymers and Stem Cells for Bioprinting.

PubMed

Lei, Meijuan; Wang, Xiaohong

2016-04-29

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

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

PubMed

Kitambi, Satish Srinivas; Chandrasekar, Gayathri

2011-01-01

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

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

A lineage CLOUD for neoblasts.

PubMed

Tran, Thao Anh; Gentile, Luca

2018-05-10

In planarians, pluripotency can be studied in vivo in the adult animal, making these animals a unique model system where pluripotency-based regeneration (PBR)-and its therapeutic potential-can be investigated. This review focuses on recent findings to build a cloud model of fate restriction likelihood for planarian stem and progenitor cells. Recently, a computational approach based on functional and molecular profiling at the single cell level was proposed for human hematopoietic stem cells. Based on data generated both in vivo and ex vivo, we hypothesized that planarian stem cells could acquire multiple direction lineage biases, following a "badlands" landscape. Instead of a discrete tree-like hierarchy, where the potency of stem/progenitor cells reduces stepwise, we propose a Continuum of LOw-primed UnDifferentiated Planarian Stem/Progenitor Cells (CLOUD-PSPCs). Every subclass of neoblast/progenitor cells is a cloud of likelihood, as the single cell transcriptomics data indicate. The CLOUD-HSPCs concept was substantiated by in vitro data from cell culture; therefore, to confirm the CLOUD-PSPCs model, the planarian community needs to develop new tools, like live cell tracking. Future studies will allow a deeper understanding of PBR in planarian, and the possible implications for regenerative therapies in human. Copyright © 2018 Elsevier Ltd. All rights reserved.

The maintenance of pluripotency following laser direct-write of mouse embryonic stem cells.

PubMed

Raof, Nurazhani Abdul; Schiele, Nathan R; Xie, Yubing; Chrisey, Douglas B; Corr, David T

2011-03-01

The ability to precisely pattern embryonic stem (ES) cells in vitro into predefined arrays/geometries may allow for the recreation of a stem cell niche for better understanding of how cellular microenvironmental factors govern stem cell maintenance and differentiation. In this study, a new gelatin-based laser direct-write (LDW) technique was utilized to deposit mouse ES cells into defined arrays of spots, while maintaining stem cell pluripotency. Results obtained from these studies showed that ES cells were successfully printed into specific patterns and remained viable. Furthermore, ES cells retained the expression of Oct4 in nuclei after LDW, indicating that the laser energy did not affect their maintenance of an undifferentiated state. The differentiation potential of mouse ES cells after LDW was confirmed by their ability to form embryoid bodies (EBs) and to spontaneously become cell lineages representing all three germ layers, revealed by the expression of marker proteins of nestin (ectoderm), Myf-5 (mesoderm) and PDX-1 (endoderm), after 7 days of cultivation. Gelatin-based LDW provides a new avenue for stem cell patterning, with precision and control of the cellular microenvironment. Copyright © 2010 Elsevier Ltd. All rights reserved.

Future perspective of induced pluripotent stem cells for diagnosis, drug screening and treatment of human diseases.

PubMed

Lian, Qizhou; Chow, Yenyen; Esteban, Miguel Angel; Pei, Duanqing; Tse, Hung-Fat

2010-07-01

Recent advances in stem cell biology have transformed the understanding of cell physiology and developmental biology such that it can now play a more prominent role in the clinical application of stem cell and regenerative medicine. Success in the generation of human induced pluripotent stem cells (iPS) as well as related emerging technology on the iPS platform provide great promise in the development of regenerative medicine. Human iPS cells show almost identical properties to human embryonic stem cells (ESC) in pluripotency, but avoid many of their limitations of use. In addition, investigations into reprogramming of somatic cells to pluripotent stem cells facilitate a deeper understanding of human stem cell biology. The iPS cell technology has offered a unique platform for studying the pathogenesis of human disease, pharmacological and toxicological testing, and cell-based therapy. Nevertheless, significant challenges remain to be overcome before the promise of human iPS cell technology can be realised.

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

PubMed

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

2018-02-27

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

[Bioethical challenges of stem cell tourism].

PubMed

Ventura-Juncá, Patricio; Erices, Alejandro; Santos, Manuel J

2013-08-01

Stem cells have drawn extraordinary attention from scientists and the general public due to their potential to generate effective therapies for incurable diseases. At the same time, the production of embryonic stem cells involves a serious ethical issue concerning the destruction of human embryos. Although adult stem cells and induced pluripotential cells do not pose this ethical objection, there are other bioethical challenges common to all types of stem cells related particularly to the clinical use of stem cells. Their clinical use should be based on clinical trials, and in special situations, medical innovation, both of which have particular ethical dimensions. The media has raised unfounded expectations in patients and the public about the real clinical benefits of stem cells. At the same time, the number of unregulated clinics is increasing around the world, making direct offers through Internet of unproven stem cell therapies that attract desperate patients that have not found solutions in standard medicine. This is what is called stem cells tourism. This article reviews this situation, its consequences and the need for international cooperation to establish effective regulations to prevent the exploitation of patients and to endanger the prestige of legitimate stem cell research.

Training stem cells for treatment of malignant brain tumors

PubMed Central

Li, Shengwen Calvin; Kabeer, Mustafa H; Vu, Long T; Keschrumrus, Vic; Yin, Hong Zhen; Dethlefs, Brent A; Zhong, Jiang F; Weiss, John H; Loudon, William G

2014-01-01

The treatment of malignant brain tumors remains a challenge. Stem cell technology has been applied in the treatment of brain tumors largely because of the ability of some stem cells to infiltrate into regions within the brain where tumor cells migrate as shown in preclinical studies. However, not all of these efforts can translate in the effective treatment that improves the quality of life for patients. Here, we perform a literature review to identify the problems in the field. Given the lack of efficacy of most stem cell-based agents used in the treatment of malignant brain tumors, we found that stem cell distribution (i.e., only a fraction of stem cells applied capable of targeting tumors) are among the limiting factors. We provide guidelines for potential improvements in stem cell distribution. Specifically, we use an engineered tissue graft platform that replicates the in vivo microenvironment, and provide our data to validate that this culture platform is viable for producing stem cells that have better stem cell distribution than with the Petri dish culture system. PMID:25258664

Further insights into the characterization of equine adipose tissue-derived mesenchymal stem cells.

PubMed

Raabe, Oksana; Shell, Katja; Würtz, Antonia; Reich, Christine Maria; Wenisch, Sabine; Arnhold, Stefan

2011-08-01

Adipose tissue-derived stem cells (ADSCs) represent a promising subpopulation of adult stem cells for tissue engineering applications in veterinary medicine. In this study we focused on the morphological and molecular biological properties of the ADSCs. The expression of stem cell markers Oct4, Nanog and the surface markers CD90 and CD105 were detected using RT-PCR. ADSCs showed a proliferative potential and were capable of adipogenic and osteogenic differentiation. Expression of Alkaline phosphatase (AP), phosphoprotein (SPP1), Runx2 and osteocalcin (OC) mRNA were positive in osteogenic lineages and peroxisome proliferator activated receptor (Pparγ2) mRNA was positive in adipogenic lineages. ADSCs show stem cell and surface marker profiles and differentiation characteristics that are similar to but distinct from other adult stem cells, such as bone marrow-derived mesenchymal stem cells (BM-MSCs). The availability of an easily accessible and reproducible cell source may greatly facilitate the development of stem cell based tissue engineering and therapies for regenerative equine medicine.

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

PubMed Central

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

2017-01-01

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

Stem Cell Niche, the Microenvironment and Immunological Crosstalk

PubMed Central

Sujata, Law; Chaudhuri, S

2008-01-01

The concept of stem cells, their physiological existence, the intricate anatomical localization, the known and the unknown functions, and their exclusive utility for the purpose of regenerative medicine, are all now encompassed within an emergent question, ‘how compatible these cells are immunologically?' Indeed, the medical aspects of stem cells are dependent on a large number of queries based on the basic properties of the cells. It has greatly been emphasized to probe into the basic research on stem cells before any successful therapeutic attempts are made. One of the intricate aspects of the adult stem cells is its immunological behavior in relation to the microenvironmental associates, the stromal cells in the presence of a suitable target. PMID:18445340

Stem cell niche, the microenvironment and immunological crosstalk.

PubMed

Sujata, Law; Chaudhuri, S

2008-04-01

The concept of stem cells, their physiological existence, the intricate anatomical localization, the known and the unknown functions, and their exclusive utility for the purpose of regenerative medicine, are all now encompassed within an emergent question, 'how compatible these cells are immunologically?' Indeed, the medical aspects of stem cells are dependent on a large number of queries based on the basic properties of the cells. It has greatly been emphasized to probe into the basic research on stem cells before any successful therapeutic attempts are made. One of the intricate aspects of the adult stem cells is its immunological behavior in relation to the microenvironmental associates, the stromal cells in the presence of a suitable target.

Stem cell tourism--a web-based analysis of clinical services available to international travellers.

PubMed

Connolly, Ruairi; O'Brien, Timothy; Flaherty, Gerard

2014-01-01

Stem cell therapies are advertised through online resources which describe a range of treatments with diverse clinical indications. Stem cell tourists may not be aware of the information they should seek when consulting these clinics, or of the potential risks involved. The aim of this study was to characterise the therapies offered by online stem cell clinics. A web based search utilising five search terms was employed. The first twenty pages of each search result were screened against 340 variables. 224 out of 1091 websites advertised stem cell clinics. 68 eligible sites covering 21 countries were evaluated. The top five clinical indications for stem cell therapy were multiple sclerosis, anti-ageing, Parkinson's disease, stroke and spinal cord injury. Adult, autologous stem cells were the most commonly utilised stem cell, and these were frequently sourced from bone marrow and adipose tissue and administered intravenously. Thirty-four per cent of sites mentioned the number of patients treated while one quarter of clinics provided outcome data. Twenty-nine per cent of clinics had an internationally recognised accreditation. Fifteen per cent of clinics stated that their therapies posed no risk. Eighty-eight per cent of clinics claimed treatment effectiveness, with 16% describing their curative potential. Over 40% of sites did not specify the number or duration of treatments. Fifty-three per cent of clinics requested access to patients' medical records, and 12% recommended patients discuss the proposed therapy with their doctor. No clinic recommended that travellers consult a travel medicine specialist or receive vaccinations prior to their intended travel. One quarter of sites discussed contraindications to treatment, with 41% of sites detailing follow up patient care. There is potential for stem cell tourists to receive misleading or deficient information from online stem cell clinics. Both the stem cell tourist and travel medicine practitioner should be educated on the potential risks associated with stem cell clinical services advertised online.

TGFβ lengthens the G1 phase of stem cells in aged mouse brain.

PubMed

Daynac, Mathieu; Pineda, Jose R; Chicheportiche, Alexandra; Gauthier, Laurent R; Morizur, Lise; Boussin, François D; Mouthon, Marc-André

2014-12-01

Neurogenesis decreases during aging causing a progressive cognitive decline but it is still controversial whether proliferation defects in neurogenic niches result from a loss of neural stem cells or from an impairment of their progression through the cell cycle. Using an accurate fluorescence-activated cell sorting technique, we show that the pool of neural stem cells is maintained in the subventricular zone of middle-aged mice while they have a reduced proliferative potential eventually leading to the subsequent decrease of their progeny. In addition, we demonstrate that the G1 phase is lengthened during aging specifically in activated stem cells, but not in transit-amplifying cells, and directly impacts on neurogenesis. Finally, we report that inhibition of TGFβ signaling restores cell cycle progression defects in stem cells. Our data highlight the significance of cell cycle dysregulation in stem cells in the aged brain and provide an attractive foundation for the development of anti-TGFβ regenerative therapies based on stimulating endogenous neural stem cells. © 2014 AlphaMed Press.

Clinical application of adipose stem cells in plastic surgery.

PubMed

Kim, Yong-Jin; Jeong, Jae-Ho

2014-04-01

Adipose stem cells (ASCs) are a type of adult stem cells that share common characteristics with typical mesenchymal stem cells. In the last decade, ASCs have been shown to be a useful cell resource for tissue regeneration. The major role of regenerative medicine in this century is based on cell therapy in which ASCs hold a key position. Active research on this new type of adult stem cell has been ongoing and these cells now have several clinical applications, including fat grafting, overcoming wound healing difficulties, recovery from local tissue ischemia, and scar remodeling. The application of cultured cells will increase the efficiency of cell therapy. However, the use of cultured stem cells is strictly controlled by government regulation to ensure patient safety. Government regulation is a factor that can limit more versatile clinical application of ASCs. In this review, current clinical applications of ASCs in plastic surgery are introduced. Future stem cell applications in clinical field including culturing and banking of ASCs are also discussed in this review.

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.

Nanoparticle-mediated transcriptional modification enhances neuronal differentiation of human neural stem cells following transplantation in rat brain.

PubMed

Li, Xiaowei; Tzeng, Stephany Y; Liu, Xiaoyan; Tammia, Markus; Cheng, Yu-Hao; Rolfe, Andrew; Sun, Dong; Zhang, Ning; Green, Jordan J; Wen, Xuejun; Mao, Hai-Quan

2016-04-01

Strategies to enhance survival and direct the differentiation of stem cells in vivo following transplantation in tissue repair site are critical to realizing the potential of stem cell-based therapies. Here we demonstrated an effective approach to promote neuronal differentiation and maturation of human fetal tissue-derived neural stem cells (hNSCs) in a brain lesion site of a rat traumatic brain injury model using biodegradable nanoparticle-mediated transfection method to deliver key transcriptional factor neurogenin-2 to hNSCs when transplanted with a tailored hyaluronic acid (HA) hydrogel, generating larger number of more mature neurons engrafted to the host brain tissue than non-transfected cells. The nanoparticle-mediated transcription activation method together with an HA hydrogel delivery matrix provides a translatable approach for stem cell-based regenerative therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Of mice and women: a comparative tissue biology perspective of breast stem cells and differentiation.

PubMed

Dontu, Gabriela; Ince, Tan A

2015-06-01

Tissue based research requires a background in human and veterinary pathology, developmental biology, anatomy, as well as molecular and cellular biology. This type of comparative tissue biology (CTB) expertise is necessary to tackle some of the conceptual challenges in human breast stem cell research. It is our opinion that the scarcity of CTB expertise contributed to some erroneous interpretations in tissue based research, some of which are reviewed here in the context of breast stem cells. In this article we examine the dissimilarities between mouse and human mammary tissue and suggest how these may impact stem cell studies. In addition, we consider the differences between breast ducts vs. lobules and clarify how these affect the interpretation of results in stem cell research. Lastly, we introduce a new elaboration of normal epithelial cell types in human breast and discuss how this provides a clinically useful basis for breast cancer classification.

Redefining the potential applications of dental stem cells: An asset for future

PubMed Central

Rai, Shalu; Kaur, Mandeep; Kaur, Sandeep; Arora, Sapna Panjwani

2012-01-01

Recent exciting discoveries isolated dental stem cells from the pulp of the primary and permanent teeth, from the periodontal ligament, and from associated healthy tissues. Dental pulp stem cells (DPSCs) represent a kind of adult cell colony which has the potent capacity of self-renewing and multilineage differentiation. Stem cell-based tooth engineering is deemed as a promising approach to the making of a biological tooth (bio-tooth) or engineering of functional tooth structures. Dental professionals have the opportunity to make their patients aware of these new sources of stem cells that can be stored for future use as new therapies are developed for a range of diseases and injuries. The aim of this article is to review and understand how dental stem cells are being used for regeneration of oral and conversely nonoral tissues. A brief review on banking is also done for storing of these valuable stem cells for future use. PMID:23716933

Identifying niche-mediated regulatory factors of stem cell phenotypic state: a systems biology approach.

PubMed

Ravichandran, Srikanth; Del Sol, Antonio

2017-02-01

Understanding how the cellular niche controls the stem cell phenotype is often hampered due to the complexity of variegated niche composition, its dynamics, and nonlinear stem cell-niche interactions. Here, we propose a systems biology view that considers stem cell-niche interactions as a many-body problem amenable to simplification by the concept of mean field approximation. This enables approximation of the niche effect on stem cells as a constant field that induces sustained activation/inhibition of specific stem cell signaling pathways in all stem cells within heterogeneous populations exhibiting the same phenotype (niche determinants). This view offers a new basis for the development of single cell-based computational approaches for identifying niche determinants, which has potential applications in regenerative medicine and tissue engineering. © 2017 The Authors. FEBS Letters published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.

Guidelines for stem cell science and clinical translation.

PubMed

Pandya, Sunil K

2016-01-01

The International Society for Stem Cell Research has released its updated guidelines for stem cell research in order to provide "assurance that stem cell research is conducted with scientific and ethical integrity and that new therapies are evidence-based." The guidelines were updated by a Guidelines Update Task Force consisting of twenty-five scientists, ethicists and experts in health care policy from nine countries. The chairpersons of this task force are Jonathan Kimmelman, George Daley and Insoo Hyun. There is no representative from India; the only person of Indian origin on it, Mahendra Rao, represents The New York Stem Cell Foundation.

Nanomaterials for Engineering Stem Cell Responses.

PubMed

Kerativitayanan, Punyavee; Carrow, James K; Gaharwar, Akhilesh K

2015-08-05

Recent progress in nanotechnology has stimulated the development of multifunctional biomaterials for tissue engineering applications. Synergistic interactions between nanomaterials and stem cell engineering offer numerous possibilities to address some of the daunting challenges in regenerative medicine, such as controlling trigger differentiation, immune reactions, limited supply of stem cells, and engineering complex tissue structures. Specifically, the interactions between stem cells and their microenvironment play key roles in controlling stem cell fate, which underlines therapeutic success. However, the interactions between nanomaterials and stem cells are not well understood, and the effects of the nanomaterials shape, surface morphology, and chemical functionality on cellular processes need critical evaluation. In this Review, focus is put on recent development in nanomaterial-stem cell interactions, with specific emphasis on their application in regenerative medicine. Further, the emerging technologies based on nanomaterials developed over the past decade for stem cell engineering are reviewed, as well as the potential applications of these nanomaterials in tissue regeneration, stem cell isolation, and drug/gene delivery. It is anticipated that the enhanced understanding of nanomaterial-stem cell interactions will facilitate improved biomaterial design for a range of biomedical and biotechnological applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Knowledge and Attitude about Stem Cells and Their Application in Medicine among Nursing Students in Universiti Sains Malaysia, Malaysia

PubMed Central

LYE, Jee Leng; SOON, Lean Keng; WAN AHMAD, Wan Amir Nizam; TAN, Suat Cheng

2015-01-01

Background: Stem cell research has been extensively explored worldwide to enhance human health in medical setting. Nevertheless, there is currently no full understanding of the stem cell knowledge and attitude levels among student nurses in Malaysia. This study aimed to assess the level of stem cell knowledge, attitude toward stem cell application in medicine, and its association with years of education, among Universiti Sains Malaysia (USM) undergraduate nursing students. Methods: A cross-sectional study (n = 88) was conducted using self-administered questionnaire consisted of demographic information, stem cells knowledge and attitude statements. Data was analysed using Statistical Package Social Software 20.0. Results: The majority of participants (92%) had moderate knowledge score about stem cells. Many students (33%) worried that stem cell application might cause a harm to humanity yet had a positive (76.1%) attitude towards its therapeutic potential (45.5%). Poor correlation between knowledge and attitude (r = 0.08) indicated that acceptance towards stem cell is not solely based on the knowledge level but also on other factors including religion and culture. Conclusion: Therefore, this study suggests that various educational programs on stem cell should be implemented considering the religion, cultural, social, and behavioural determinants in the population to improve stem cell knowledge and encourage a more positive attitude towards stem cells in medicine among these nursing students. PMID:26715905

Knowledge and Attitude about Stem Cells and Their Application in Medicine among Nursing Students in Universiti Sains Malaysia, Malaysia.

PubMed

Lye, Jee Leng; Soon, Lean Keng; Wan Ahmad, Wan Amir Nizam; Tan, Suat Cheng

2015-01-01

Stem cell research has been extensively explored worldwide to enhance human health in medical setting. Nevertheless, there is currently no full understanding of the stem cell knowledge and attitude levels among student nurses in Malaysia. This study aimed to assess the level of stem cell knowledge, attitude toward stem cell application in medicine, and its association with years of education, among Universiti Sains Malaysia (USM) undergraduate nursing students. A cross-sectional study (n = 88) was conducted using self-administered questionnaire consisted of demographic information, stem cells knowledge and attitude statements. Data was analysed using Statistical Package Social Software 20.0. The majority of participants (92%) had moderate knowledge score about stem cells. Many students (33%) worried that stem cell application might cause a harm to humanity yet had a positive (76.1%) attitude towards its therapeutic potential (45.5%). Poor correlation between knowledge and attitude (r = 0.08) indicated that acceptance towards stem cell is not solely based on the knowledge level but also on other factors including religion and culture. Therefore, this study suggests that various educational programs on stem cell should be implemented considering the religion, cultural, social, and behavioural determinants in the population to improve stem cell knowledge and encourage a more positive attitude towards stem cells in medicine among these nursing students.

Novel surface-enhanced Raman scattering-based assays for ultra-sensitive detection of human pluripotent stem cells.

PubMed

Han, Jingjia; Qian, Ximei; Wu, Qingling; Jha, Rajneesh; Duan, Jinshuai; Yang, Zhou; Maher, Kevin O; Nie, Shuming; Xu, Chunhui

2016-10-01

Human pluripotent stem cells (hPSCs) are a promising cell source for regenerative medicine, but their derivatives need to be rigorously evaluated for residual stem cells to prevent teratoma formation. Here, we report the development of novel surface-enhanced Raman scattering (SERS)-based assays that can detect trace numbers of undifferentiated hPSCs in mixed cell populations in a highly specific, ultra-sensitive, and time-efficient manner. By targeting stem cell surface markers SSEA-5 and TRA-1-60 individually or simultaneously, these SERS assays were able to identify as few as 1 stem cell in 10(6) cells, a sensitivity (0.0001%) which was ∼2000 to 15,000-fold higher than that of flow cytometry assays. Using the SERS assay, we demonstrate that the aggregation of hPSC-based cardiomyocyte differentiation cultures into 3D spheres significantly reduced SSEA-5(+) and TRA-1-60(+) cells compared with parallel 2D cultures. Thus, SERS may provide a powerful new technology for quality control of hPSC-derived products for preclinical and clinical applications. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

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.

The stem cell patent landscape as relevant to cancer vaccines.

PubMed

Wang, Shyh-Jen

2011-10-01

Cancer vaccine targeting cancer stem cells is proposed to serve as a potent immunotherapy. Thus, it would be useful to examine the main trends in stem cell patenting activity as a guide for those seeking to develop such cancer vaccines. We found that a substantial number of stem cell patents were granted up to the end of 2010, including ~2000 issued in the US. Many of these have been filed since 2001, including 7,551 applications in the US. Stem cell development, as evidenced by the numbers of PubMed articles, has matured steadily in recent years. However, the other metrics, such as the number of patent applications, the technology-science linkage and the number of patent assignees, have been stagnant. Moreover, the ownership of stem cell patents is still quiet fragmented across multiple organizations, and the number of stem cell patent assignees from the business sector has not increased significantly. Academic and nonprofit institutions not only account for a large share of stem cell patents but also apply for patents continually. Based on this analysis, the strength of stem cell resources seems to remain stagnant in recent years due to the ban on government funding of embryonic stem cell research. Furthermore, the patent prosecution or technical barriers in the field of stem cells would be another main reason that the number of US-issued stem cell patents for each application have been in gradual decline since 2000. Therefore, we consider stem cell technology to still be under development.

Fraudsters operate and officialdom turns a blind eye: a proposal for controlling stem cell therapy in China.

PubMed

Jiang, Li; Dong, Bing He

2016-09-01

Stem cell tourism-the flow of patients from home countries to destination countries to obtain stem cell treatment-is a growing business in China. Many concerns have been raised regarding fraudsters that operate unsafe stem cell therapies and an officialdom that turns a blind eye to the questionable technology. The Chinese regulatory approach to stem cell research is based on Guidelines and Administrative Measures, rather than legislation, and may have no binding force on certain institutions, such as military hospitals. There is no liability and traceability system and no visible set of penalties for non-compliance in the stem cell legal framework. In addition to the lack of safety and efficacy systems in the regulations, no specific expert authority has been established to monitor stem cell therapy to date. Recognizing the global nature of stem cell tourism, this article argues that resolving stem cell tourism issues may require not only the Chinese government but also an international mechanism for transparency and ethical oversight. A stringent set of international regulations that govern stem cell therapies can encourage China to improve stem cell regulation and enforcement to fulfill its obligations. Through an international consensus, a minimum standard for clinical stem cell research and a central enforcement system will be provided. As a result, rogue clinics that conduct unauthorized stem cell therapies can be penalized, and countries that are reluctant to implement the reconciled regulations should be sanctioned.

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

De Novo Kidney Regeneration with Stem Cells

PubMed Central

Yokote, Shinya; Yamanaka, Shuichiro; Yokoo, Takashi

2012-01-01

Recent studies have reported on techniques to mobilize and activate endogenous stem-cells in injured kidneys or to introduce exogenous stem cells for tissue repair. Despite many recent advantages in renal regenerative therapy, chronic kidney disease (CKD) remains a major cause of morbidity and mortality and the number of CKD patients has been increasing. When the sophisticated structure of the kidneys is totally disrupted by end stage renal disease (ESRD), traditional stem cell-based therapy is unable to completely regenerate the damaged tissue. This suggests that whole organ regeneration may be a promising therapeutic approach to alleviate patients with uncured CKD. We summarize here the potential of stem-cell-based therapy for injured tissue repair and de novo whole kidney regeneration. In addition, we describe the hurdles that must be overcome and possible applications of this approach in kidney regeneration. PMID:23251079

Cardiotoxicity evaluation using human embryonic stem cells and induced pluripotent stem cell-derived cardiomyocytes.

PubMed

Zhao, Qi; Wang, Xijie; Wang, Shuyan; Song, Zheng; Wang, Jiaxian; Ma, Jing

2017-03-09

Cardiotoxicity remains an important concern in drug discovery. Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) have become an attractive platform to evaluate cardiotoxicity. However, the consistency between human embryonic stem cell-derived cardiomyocytes (hESC-CMs) and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) in prediction of cardiotoxicity has yet to be elucidated. Here we screened the toxicities of four representative drugs (E-4031, isoprenaline, quinidine, and haloperidol) using both hESC-CMs and hiPSC-CMs, combined with an impedance-based bioanalytical method. It showed that both hESC-CMs and hiPSC-CMs can recapitulate cardiotoxicity and identify the effects of well-characterized compounds. The combined platform of hPSC-CMs and an impedance-based bioanalytical method could improve preclinical cardiotoxicity screening, holding great potential for increasing drug development accuracy.

Biomaterials for 4D stem cell culture

PubMed Central

Hilderbrand, Amber M.; Ovadia, Elisa M.; Rehmann, Matthew S.; Kharkar, Prathamesh M.; Guo, Chen; Kloxin, April M.

2017-01-01

Stem cells reside in complex three-dimensional (3D) environments within the body that change with time, promoting various cellular functions and processes such as migration and differentiation. These complex changes in the surrounding environment dictate cell fate yet, until recently, have been challenging to mimic within cell culture systems. Hydrogel-based biomaterials are well suited to mimic aspects of these in vivo environments, owing to their high water content, soft tissue-like elasticity, and often-tunable biochemical content. Further, hydrogels can be engineered to achieve changes in matrix properties over time to better mimic dynamic native microenvironments for probing and directing stem cell function and fate. This review will focus on techniques to form hydrogel-based biomaterials and modify their properties in time during cell culture using select addition reactions, cleavage reactions, or non-covalent interactions. Recent applications of these techniques for the culture of stem cells in four dimensions (i.e., in three dimensions with changes over time) also will be discussed for studying essential stem cell processes. PMID:28717344

[A comparative study on inducing non-homologous mesenchymal stem cells to differentiate into neural stem cells using non-homologous cerebrospinal fluid].

PubMed

Ren, Chao; Liu, Xiaoyun; Wan, Meirong; Geng, Deqin; Ge, Wei; Li, Jinmei; Zhang, Weiwei

2013-12-01

In order to set up a base for stem cells to be widely used in clinical medicine, we tried to optimize, in this study, the technique that induces human mesenchymal stem cells (hMSCs) to differentiate into neural stem cells by using cerebrospinal fluid (CSF) from the different groups. After the induction, presence of neural stem cells was confirmed with microscope observation, flow cytometry analysis, immunohistochemistry and fluorescent immunohistochemistry. At the same time, we also compared and analysed the data of the number of stem cells when it totally met the requirements for clinical treatment and the days required. At last, we confirmed that hMSCs could be induced to differentiate into neural stem cells, and that the number of cells totally met the requirements for clinical treatment. But there were some differences both in the number of cells and the days required. Among the groups, the group that marrow mesenchymal stem cells from patients own induced by CSF from healthy volunteers used the shortest time and the quantity of the cells was significantly higher than those of the others.

Vitamin C treatment promotes mesenchymal stem cell sheet formation and tissue regeneration by elevating telomerase activity.

PubMed

Wei, Fulan; Qu, Cunye; Song, Tieli; Ding, Gang; Fan, Zhipeng; Liu, Dayong; Liu, Yi; Zhang, Chunmei; Shi, Songtao; Wang, Songlin

2012-09-01

Cell sheet engineering has been developed as an alternative approach to improve mesenchymal stem cell-mediated tissue regeneration. In this study, we found that vitamin C (Vc) was capable of inducing telomerase activity in periodontal ligament stem cells (PDLSCs), leading to the up-regulated expression of extracellular matrix type I collagen, fibronectin, and integrin β1, stem cell markers Oct4, Sox2, and Nanog as well as osteogenic markers RUNX2, ALP, OCN. Under Vc treatment, PDLSCs can form cell sheet structures because of increased cell matrix production. Interestingly, PDLSC sheets demonstrated a significant improvement in tissue regeneration compared with untreated control dissociated PDLSCs and offered an effective treatment for periodontal defects in a swine model. In addition, bone marrow mesenchymal stem cell sheets and umbilical cord mesenchymal stem cell sheets were also well constructed using this method. The development of Vc-mediated mesenchymal stem cell sheets may provide an easy and practical approach for cell-based tissue regeneration. Copyright © 2011 Wiley Periodicals, Inc.

Manifestations and mechanisms of stem cell aging

PubMed Central

Liu, Ling

2011-01-01

Adult stem cells exist in most mammalian organs and tissues and are indispensable for normal tissue homeostasis and repair. In most tissues, there is an age-related decline in stem cell functionality but not a depletion of stem cells. Such functional changes reflect deleterious effects of age on the genome, epigenome, and proteome, some of which arise cell autonomously and others of which are imposed by an age-related change in the local milieu or systemic environment. Notably, some of the changes, particularly epigenomic and proteomic, are potentially reversible, and both environmental and genetic interventions can result in the rejuvenation of aged stem cells. Such findings have profound implications for the stem cell–based therapy of age-related diseases. PMID:21502357

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

PubMed

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

2017-09-12

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

Stem cells for the treatment of neurological disorders

NASA Astrophysics Data System (ADS)

Lindvall, Olle; Kokaia, Zaal

2006-06-01

Many common neurological disorders, such as Parkinson's disease, stroke and multiple sclerosis, are caused by a loss of neurons and glial cells. In recent years, neurons and glia have been generated successfully from stem cells in culture, fuelling efforts to develop stem-cell-based transplantation therapies for human patients. More recently, efforts have been extended to stimulating the formation and preventing the death of neurons and glial cells produced by endogenous stem cells within the adult central nervous system. The next step is to translate these exciting advances from the laboratory into clinically useful therapies.

Cultivating stem cells for treating amyotrophic lateral sclerosis

PubMed Central

Li, Shengwen Calvin; Yin, Hong Zhen; Loudon, William G; Weiss, John H

2012-01-01

This editorial addresses the current challenges and future directions in the use of stem cells as an approach for treating amyotrophic lateral sclerosis. A wide variety of literature has been reviewed to enlighten the reader on the many facets of stem cell research that are important to consider before using them for a cell based therapy. PMID:23516096

Follicle and melanocyte stem cells, and their application in neuroscience: A Web of Science-based literature analysis.

PubMed

Wu, Weifu

2012-12-05

To identify global research trends of follicle and melanocyte stem cells, and their application in neuroscience. We performed a bibliometric analysis of studies from 2002 to 2011 on follicle and melanocyte stem cells, and their application in neuroscience, which were retrieved from the Web of Science, using the key words follicle stem cell or melanocyte stem cell, and neural, neuro or nerve. (a) peer-reviewed published articles on follicle and melanocyte stem cells, and their application in neuroscience, which were indexed in the Web of Science; (b) original research articles, reviews, meeting abstracts, proceedings papers, book chapters, editorial material, and news items. (a) articles that required manual searching or telephone access; (b) documents that were not published in the public domain; and (c) a number of corrected papers from the total number of articles. (1) Distribution of publications on follicle and melanocyte stem cells by years, journals, countries, institutions, institutions in China, and most cited papers. (2) Distribution of publications on the application of follicle and melanocyte stem cells in neuroscience by years, journals, countries, institutions, and most cited papers. Of the 348 publications from 2002 to 2011 on follicle and melanocyte stem cells, which were retrieved from the Web of Science, more than half were from American authors and institutes. The most prolific institutions in China for publication of papers on follicle and melanocyte stem cells were the Fourth Military Medical University and Third Military Medical University. The most prolific journals for publication of papers on follicle and melanocyte stem cells were the Journal of Investigative Dermatology, Pigment Cell & Melanoma Research. Of the 63 publications from 2002 to 2011 on the application of follicle and melanocyte stem cells in neuroscience, which were retrieved from the Web of Science, more than half were from American authors and institutes, and no papers were from Chinese authors and institutes. The most prolific journals for publication of papers on the application of follicle and melanocyte stem cells in neuroscience were the Journal of Investigative Dermatology, Pigment Cell & Melanoma Research. Based on our analysis of the literature and research trends, we found that follicle stem cells might offer further benefits in neural regenerative medicine.

Cardiac side population cells and Sca-1-positive cells.

PubMed

Nagai, Toshio; Matsuura, Katsuhisa; Komuro, Issei

2013-01-01

Since the resident cardiac stem/progenitor cells were discovered, their ability to maintain the architecture and functional integrity of adult heart has been broadly explored. The methods for isolation and purification of the cardiac stem cells are crucial for the precise analysis of their developmental origin and intrinsic potential as tissue stem cells. Stem cell antigen-1 (Sca-1) is one of the useful cell surface markers to purify the cardiac progenitor cells. Another purification strategy is based on the high efflux ability of the dye, which is a common feature of tissue stem cells. These dye-extruding cells have been called side population cells because they locate in the side of dye-retaining cells after fluorescent cell sorting. In this chapter, we describe the methodology for the isolation of cardiac SP cells and Sca-1 positive cells.

Evaluation of the osteogenic differentiation of gingiva-derived stem cells grown on culture plates or in stem cell spheroids: Comparison of two- and three-dimensional cultures.

PubMed

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

2017-09-01

Three-dimensional cell culture systems provide a convenient in vitro model for the study of complex cell-cell and cell-matrix interactions in the absence of exogenous substrates. The current study aimed to evaluate the osteogenic differentiation potential of gingiva-derived stem cells cultured in two-dimensional or three-dimensional systems. To the best of our knowledge, the present study is the first to compare the growth of gingiva-derived stem cells in monolayer culture to a three-dimensional culture system with microwells. For three-dimensional culture, gingiva-derived stem cells were isolated and seeded into polydimethylsiloxane-based concave micromolds. Alkaline phosphatase activity and alizarin red S staining assays were then performed to evaluate osteogenesis and the degree of mineralization, respectively. Stem cell spheroids had a significantly increased level of alkaline phosphatase activity and mineralization compared with cells from the two-dimensional culture. In addition, an increase in mineralized deposits was observed with an increase in the loading cell number. The results of present study indicate that gingiva-derived stem cell spheroids exhibit an increased osteogenic potential compared with stem cells from two-dimensional culture. This highlights the potential of three-dimensional culture systems using gingiva-derived stem cells for regenerative medicine applications requiring stem cells with osteogenic potential.

Evaluation of Stem Cell-Derived Red Blood Cells as a Transfusion Product Using a Novel Animal Model.

PubMed

Shah, Sandeep N; Gelderman, Monique P; Lewis, Emily M A; Farrel, John; Wood, Francine; Strader, Michael Brad; Alayash, Abdu I; Vostal, Jaroslav G

2016-01-01

Reliance on volunteer blood donors can lead to transfusion product shortages, and current liquid storage of red blood cells (RBCs) is associated with biochemical changes over time, known as 'the storage lesion'. Thus, there is a need for alternative sources of transfusable RBCs to supplement conventional blood donations. Extracorporeal production of stem cell-derived RBCs (stemRBCs) is a potential and yet untapped source of fresh, transfusable RBCs. A number of groups have attempted RBC differentiation from CD34+ cells. However, it is still unclear whether these stemRBCs could eventually be effective substitutes for traditional RBCs due to potential differences in oxygen carrying capacity, viability, deformability, and other critical parameters. We have generated ex vivo stemRBCs from primary human cord blood CD34+ cells and compared them to donor-derived RBCs based on a number of in vitro parameters. In vivo, we assessed stemRBC circulation kinetics in an animal model of transfusion and oxygen delivery in a mouse model of exercise performance. Our novel, chronically anemic, SCID mouse model can evaluate the potential of stemRBCs to deliver oxygen to tissues (muscle) under resting and exercise-induced hypoxic conditions. Based on our data, stem cell-derived RBCs have a similar biochemical profile compared to donor-derived RBCs. While certain key differences remain between donor-derived RBCs and stemRBCs, the ability of stemRBCs to deliver oxygen in a living organism provides support for further development as a transfusion product.

Emerging Applications of Stem Cell and Regenerative Medicine to Sports Injuries

PubMed Central

Ajibade, David A.; Vance, Danica D.; Hare, Joshua M.; Kaplan, Lee D.; Lesniak, Bryson P.

2014-01-01

Background: The treatment of sports-related musculoskeletal injuries with stem cells has become more publicized because of recent reports of high-profile athletes undergoing stem cell procedures. There has been increased interest in defining the parameters of safety and efficacy and the indications for potential use of stem cells in clinical practice. Purpose: To review the role of regenerative medicine in the treatment of sports-related injuries. Study Design: Review. Method: Relevant studies were identified through a PubMed search combining the terms stem cells and cartilage, ligament, tendon, muscle, and bone from January 2000 to August 2013. Studies and works cited in these studies were also reviewed. Results: Treatment of sports-related injuries with stem cells shows potential for clinical efficacy from the data available from basic science and animal studies. Conclusion: Cell-based therapies and regenerative medicine offer safe and potentially efficacious treatment for sports-related musculoskeletal injuries. Basic science and preclinical studies that support the possibility of enhanced recovery from sports injuries using cell-based therapies are accumulating; however, more clinical evidence is necessary to define the indications and parameters for their use. Accordingly, exposing patients to cell-based therapies could confer an unacceptable risk profile with minimal or no benefit. Continued clinical testing with animal models and clinical trials is necessary to determine the relative risks and benefits as well as the indications and methodology of treatment. PMID:26535296

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

PubMed

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

2014-01-01

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

Emerging Importance of Phytochemicals in Regulation of Stem Cells Fate via Signaling Pathways.

PubMed

Dadashpour, Mehdi; Pilehvar-Soltanahmadi, Younes; Zarghami, Nosratollah; Firouzi-Amandi, Akram; Pourhassan-Moghaddam, Mohammad; Nouri, Mohammad

2017-11-01

To reach ideal therapeutic potential of stem cells for regenerative medicine purposes, it is essential to retain their self-renewal and differentiation capacities. Currently, biological factors are extensively used for stemness maintaining and differentiation induction of stem cells. However, low stability, high cost, complicated production process, and risks associated with viral/endotoxin infection hamper the widespread use of biological factors in the stem cell biology. Moreover, regarding the modulation of several signaling cascades, which lead to a distinct fate, phytochemicals are preferable in the stem cells biology because of their efficiency. Considering the issues related to the application of biological factors and potential advantages of phytochemicals in stem cell engineering, there is a considerable increasing trend in studies associated with the application of novel alternative molecules in the stem cell biology. In support of this statement, we aimed to highlight the various effects of phytochemicals on signaling cascades involved in commitment of stem cells. Hence, in this review, the current trends in the phytochemicals-based modulation of stem cell fate have been addressed. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

CD133 Is Not Suitable Marker for Isolating Melanoma Stem Cells from D10 Cell Line.

PubMed

Rajabi Fomeshi, Motahareh; Ebrahimi, Marzieh; Mowla, Seyed Javad; Firouzi, Javad; Khosravani, Pardis

2016-01-01

Cutaneous melanoma is the most hazardous malignancy of skin cancer with a high mortality rate. It has been reported that cancer stem cells (CSCs) are responsible for malignancy in most of cancers including melanoma. The aim of this study is to compare two common methods for melanoma stem cell enriching; isolating based on the CD133 cell surface marker and spheroid cell culture. In this experimental study, melanoma stem cells were enriched by fluorescence activated cell sorting (FACS) based on the CD133 protein expression and spheroid culture of D10 melanoma cell line,. To determine stemness features, the mRNA expression analysis of ABCG2, c-MYC, NESTIN, OCT4-A and -B genes as well as colony and spheroid formation assays were utilized in unsorted CD133(+), CD133(-) and spheroid cells. Significant differences of the two experimental groups were compared using student's t tests and a two-tailed value of P<0.05 was statistically considered as a significant threshold. Our results demonstrated that spheroid cells had more colony and spheroid forming ability, rather than CD133(+) cells and the other groups. Moreover, melanospheres expressed higher mRNA expression level of ABCG2, c-MYC, NESTIN and OCT4-A com- pared to other groups (P<0.05). Although CD133(+) derived melanoma cells represented stemness fea- tures, our findings demonstrated that spheroid culture could be more effective meth- od to enrich melanoma stem cells.

CD133 Is Not Suitable Marker for Isolating Melanoma Stem Cells from D10 Cell Line

PubMed Central

Rajabi Fomeshi, Motahareh; Ebrahimi, Marzieh; Mowla, Seyed Javad; Firouzi, Javad; Khosravani, Pardis

2016-01-01

Objective Cutaneous melanoma is the most hazardous malignancy of skin cancer with a high mortality rate. It has been reported that cancer stem cells (CSCs) are responsible for malignancy in most of cancers including melanoma. The aim of this study is to compare two common methods for melanoma stem cell enriching; isolating based on the CD133 cell surface marker and spheroid cell culture. Materials and Methods In this experimental study, melanoma stem cells were enriched by fluorescence activated cell sorting (FACS) based on the CD133 protein expression and spheroid culture of D10 melanoma cell line,. To determine stemness features, the mRNA expression analysis of ABCG2, c-MYC, NESTIN, OCT4-A and -B genes as well as colony and spheroid formation assays were utilized in unsorted CD133+, CD133- and spheroid cells. Significant differences of the two experimental groups were compared using student’s t tests and a two-tailed value of P<0.05 was statistically considered as a significant threshold. Results Our results demonstrated that spheroid cells had more colony and spheroid forming ability, rather than CD133+ cells and the other groups. Moreover, melanospheres expressed higher mRNA expression level of ABCG2, c-MYC, NESTIN and OCT4-A com- pared to other groups (P<0.05). Conclusion Although CD133+ derived melanoma cells represented stemness fea- tures, our findings demonstrated that spheroid culture could be more effective meth- od to enrich melanoma stem cells. PMID:27054115

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

PubMed

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

2017-10-05

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

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

Functional Tooth Restoration by Allogeneic Mesenchymal Stem Cell-Based Bio-Root Regeneration in Swine

PubMed Central

Wei, Fulan; Song, Tieli; Ding, Gang; Xu, Junji; Liu, Yi; Liu, Dayong; Fan, Zhipeng; Zhang, Chunmei

2013-01-01

Our previous proof-of-concept study showed the feasibility of regenerating the dental stem cell-based bioengineered tooth root (bio-root) structure in a large animal model. Here, we used allogeneic dental mesenchymal stem cells to regenerate bio-root, and then installed a crown on the bio-root to restore tooth function. A root shape hydroxyapatite tricalcium phosphate scaffold containing dental pulp stem cells was covered by a Vc-induced periodontal ligament stem cell sheet and implanted into a newly generated jaw bone implant socket. Six months after implantation, a prefabricated porcelain crown was cemented to the implant and subjected to tooth function. Clinical, radiological, histological, ultrastructural, systemic immunological evaluations and mechanical properties were analyzed for dynamic changes in the bio-root structure. The regenerated bio-root exhibited characteristics of a normal tooth after 6 months of use, including dentinal tubule-like and functional periodontal ligament-like structures. No immunological response to the bio-roots was observed. We developed a standard stem cell procedure for bio-root regeneration to restore adult tooth function. This study is the first to successfully regenerate a functional bio-root structure for artificial crown restoration by using allogeneic dental stem cells and Vc-induced cell sheet, and assess the recipient immune response in a preclinical model. PMID:23363023

Nanotopographical Surfaces for Stem Cell Fate Control: Engineering Mechanobiology from the Bottom

PubMed Central

Chen, Weiqiang; Shao, Yue; Li, Xiang; Zhao, Gang; Fu, Jianping

2015-01-01

Summary During embryogenesis and tissue maintenance and repair in an adult organism, a myriad of stem cells are regulated by their surrounding extracellular matrix (ECM) enriched with tissue/organ-specific nanoscale topographical cues to adopt different fates and functions. Attributed to their capability of self-renewal and differentiation into most types of somatic cells, stem cells also hold tremendous promise for regenerative medicine and drug screening. However, a major challenge remains as to achieve fate control of stem cells in vitro with high specificity and yield. Recent exciting advances in nanotechnology and materials science have enabled versatile, robust, and large-scale stem cell engineering in vitro through developments of synthetic nanotopographical surfaces mimicking topological features of stem cell niches. In addition to generating new insights for stem cell biology and embryonic development, this effort opens up unlimited opportunities for innovations in stem cell-based applications. This review is therefore to provide a summary of recent progress along this research direction, with perspectives focusing on emerging methods for generating nanotopographical surfaces and their applications in stem cell research. Furthermore, we provide a review of classical as well as emerging cellular mechano-sensing and -transduction mechanisms underlying stem cell nanotopography sensitivity and also give some hypotheses in regard to how a multitude of signaling events in cellular mechanotransduction may converge and be integrated into core pathways controlling stem cell fate in response to extracellular nanotopography. PMID:25883674

Cisplatin radiosensitizes radioresistant human mesenchymal stem cells.

PubMed

Rühle, Alexander; Perez, Ramon Lopez; Glowa, Christin; Weber, Klaus-Josef; Ho, Anthony D; Debus, Jürgen; Saffrich, Rainer; Huber, Peter E; Nicolay, Nils H

2017-10-20

Cisplatin-based chemo-radiotherapy is widely used to treat cancers with often severe therapy-associated late toxicities. While mesenchymal stem cells (MSCs) were shown to aid regeneration of cisplatin- or radiation-induced tissue lesions, the effect of the combined treatment on the stem cells remains unknown. Here we demonstrate that cisplatin treatment radiosensitized human bone marrow-derived MSCs in a dose-dependent manner and increased levels of radiation-induced apoptosis. However, the defining stem cell properties of MSCs remained largely intact after cisplatin-based chemo-radiation, and stem cell motility, adhesion, surface marker expression and the characteristic differentiation potential were not significantly influenced. The increased cisplatin-mediated radiosensitivity was associated with a cell cycle shift of MSCs towards the radiosensitive G2/M phase and increased residual DNA double-strand breaks. These data demonstrate for the first time a dose-dependent radiosensitization effect of MSCs by cisplatin. Clinically, the observed increase in radiation sensitivity and subsequent loss of regenerative MSCs may contribute to the often severe late toxicities observed after cisplatin-based chemo-radiotherapy in cancer patients.

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-based therapies for tumors in the brain: are we there yet?

PubMed

Shah, Khalid

2016-08-01

Advances in understanding adult stem cell biology have facilitated the development of novel cell-based therapies for cancer. Recent developments in conventional therapies (eg, tumor resection techniques, chemotherapy strategies, and radiation therapy) for treating both metastatic and primary tumors in the brain, particularly glioblastoma have not resulted in a marked increase in patient survival. Preclinical studies have shown that multiple stem cell types exhibit inherent tropism and migrate to the sites of malignancy. Recent studies have validated the feasibility potential of using engineered stem cells as therapeutic agents to target and eliminate malignant tumor cells in the brain. This review will discuss the recent progress in the therapeutic potential of stem cells for tumors in the brain and also provide perspectives for future preclinical studies and clinical translation. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Advances in Bone Marrow Stem Cell Therapy for Retinal Dysfunction

PubMed Central

Park, Susanna S.; Moisseiev, Elad; Bauer, Gerhard; Anderson, Johnathon D.; Grant, Maria B.; Zam, Azhar; Zawadzki, Robert J.; Werner, John S.; Nolta, Jan A.

2016-01-01

The most common cause of untreatable vision loss is dysfunction of the retina. Conditions, such as age-related macular degeneration, diabetic retinopathy and glaucoma remain leading causes of untreatable blindness worldwide. Various stem cell approaches are being explored for treatment of retinal regeneration. The rationale for using bone marrow stem cells to treat retinal dysfunction is based on preclinical evidence showing that bone marrow stem cells can rescue degenerating and ischemic retina. These stem cells have primarily paracrine trophic effects although some cells can directly incorporate into damaged tissue. Since the paracrine trophic effects can have regenerative effects on multiple cells in the retina, the use of this cell therapy is not limited to a particular retinal condition. Autologous bone marrow-derived stem cells are being explored in early clinical trials as therapy for various retinal conditions. These bone marrow stem cells include mesenchymal stem cells, mononuclear cells and CD34+ cells. Autologous therapy requires no systemic immunosuppression or donor matching. Intravitreal delivery of CD34+ cells and mononuclear cells appears to be tolerated and is being explored since some of these cells can home into the damaged retina after intravitreal administration. The safety of intravitreal delivery of mesenchymal stem cells has not been well established. This review provides an update of the current evidence in support of the use of bone marrow stem cells as treatment for retinal dysfunction. The potential limitations and complications of using certain forms of bone marrow stem cells as therapy are discussed. Future directions of research include methods to optimize the therapeutic potential of these stem cells, non-cellular alternatives using extracellular vesicles, and in vivo high-resolution retinal imaging to detect cellular changes in the retina following cell therapy. PMID:27784628

Genome Editing in Neuroepithelial Stem Cells to Generate Human Neurons with High Adenosine-Releasing Capacity.

PubMed

Poppe, Daniel; Doerr, Jonas; Schneider, Marion; Wilkens, Ruven; Steinbeck, Julius A; Ladewig, Julia; Tam, Allison; Paschon, David E; Gregory, Philip D; Reik, Andreas; Müller, Christa E; Koch, Philipp; Brüstle, Oliver

2018-06-01

As a powerful regulator of cellular homeostasis and metabolism, adenosine is involved in diverse neurological processes including pain, cognition, and memory. Altered adenosine homeostasis has also been associated with several diseases such as depression, schizophrenia, or epilepsy. Based on its protective properties, adenosine has been considered as a potential therapeutic agent for various brain disorders. Since systemic application of adenosine is hampered by serious side effects such as vasodilatation and cardiac suppression, recent studies aim at improving local delivery by depots, pumps, or cell-based applications. Here, we report on the characterization of adenosine-releasing human embryonic stem cell-derived neuroepithelial stem cells (long-term self-renewing neuroepithelial stem [lt-NES] cells) generated by zinc finger nuclease (ZFN)-mediated knockout of the adenosine kinase (ADK) gene. ADK-deficient lt-NES cells and their differentiated neuronal and astroglial progeny exhibit substantially elevated release of adenosine compared to control cells. Importantly, extensive adenosine release could be triggered by excitation of differentiated neuronal cultures, suggesting a potential activity-dependent regulation of adenosine supply. Thus, ZFN-modified neural stem cells might serve as a useful vehicle for the activity-dependent local therapeutic delivery of adenosine into the central nervous system. Stem Cells Translational Medicine 2018;7:477-486. © 2018 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

The Potential of Human Stem Cells for the Study and Treatment of Glaucoma

PubMed Central

Chamling, Xitiz; Sluch, Valentin M.; Zack, Donald J.

2016-01-01

Purpose Currently, the only available and approved treatments for glaucoma are various pharmacologic, laser-based, and surgical procedures that lower IOP. Although these treatments can be effective, they are not always sufficient, and they cannot restore vision that has already been lost. The goal of this review is to briefly assess current developments in the application of stem cell biology to the study and treatment of glaucoma and other forms of optic neuropathy. Methods A combined literature review and summary of the glaucoma-related discussion at the 2015 “Sight Restoration Through Stem Cell Therapy” meeting that was sponsored by the Ocular Research Symposia Foundation (ORSF). Results Ongoing advancements in basic and eye-related developmental biology have enabled researchers to direct murine and human stem cells along specific developmental paths and to differentiate them into a variety of ocular cell types of interest. The most advanced of these efforts involve the differentiation of stem cells into retinal pigment epithelial cells, work that has led to the initiation of several human trials. More related to the glaucoma field, there have been recent advances in developing protocols for differentiation of stem cells into trabecular meshwork and retinal ganglion cells. Additionally, efforts are being made to generate stem cell–derived cells that can be used to secrete neuroprotective factors. Conclusions Advancing stem cell technology provides opportunities to improve our understanding of glaucoma-related biology and develop models for drug development, and offers the possibility of cell-based therapies to restore sight to patients who have already lost vision. PMID:27116666

[CRISPR/Cas system for genome editing in pluripotent stem cells].

PubMed

Vasil'eva, E A; Melino, D; Barlev, N A

2015-01-01

Genome editing systems based on site-specific nucleases became very popular for genome editing in modern bioengineering. Human pluripotent stem cells provide a unique platform for genes function study, disease modeling, and drugs testing. Consequently, technology for fast, accurate and well controlled genome manipulation is required. CRISPR/Cas (clustered regularly interspaced short palindromic repeat/CRISPR-associated) system could be employed for these purposes. This system is based on site-specific programmable nuclease Cas9. Numerous advantages of the CRISPR/Cas system and its successful application to human stem cells provide wide opportunities for genome therapy and regeneration medicine. In this publication, we describe and compare the main genome editing systems based on site-specific programmable nucleases and discuss opportunities and perspectives of the CRISPR/Cas system for application to pluripotent stem cells.

The Immunogenicity and Immune Tolerance of Pluripotent Stem Cell Derivatives

PubMed Central

Liu, Xin; Li, Wenjuan; Fu, Xuemei; Xu, Yang

2017-01-01

Human embryonic stem cells (hESCs) can undergo unlimited self-renewal and differentiate into all cell types in human body, and therefore hold great potential for cell therapy of currently incurable diseases including neural degenerative diseases, heart failure, and macular degeneration. This potential is further underscored by the promising safety and efficacy data from the ongoing clinical trials of hESC-based therapy of macular degeneration. However, one main challenge for the clinical application of hESC-based therapy is the allogeneic immune rejection of hESC-derived cells by the recipient. The breakthrough of the technology to generate autologous-induced pluripotent stem cells (iPSCs) by nuclear reprogramming of patient’s somatic cells raised the possibility that autologous iPSC-derived cells can be transplanted into the patients without the concern of immune rejection. However, accumulating data indicate that certain iPSC-derived cells can be immunogenic. In addition, the genomic instability associated with iPSCs raises additional safety concern to use iPSC-derived cells in human cell therapy. In this review, we will discuss the mechanism underlying the immunogenicity of the pluripotent stem cells and recent progress in developing immune tolerance strategies of human pluripotent stem cell (hPSC)-derived allografts. The successful development of safe and effective immune tolerance strategy will greatly facilitate the clinical development of hPSC-based cell therapy. PMID:28626459

Unproven stem cell-based interventions and achieving a compromise policy among the multiple stakeholders.

PubMed

Matthews, Kirstin R W; Iltis, Ana S

2015-11-04

In 2004, patient advocate groups were major players in helping pass and implement significant public policy and funding initiatives in stem cells and regenerative medicine. In the following years, advocates were also actively engaged in Washington DC, encouraging policy makers to broaden embryonic stem cell research funding, which was ultimately passed after President Barack Obama came into office. Many advocates did this because they were told stem cell research would lead to cures. After waiting more than 10 years, many of these same patients are now approaching clinics around the world offering experimental stem cell-based interventions instead of waiting for scientists in the US to complete clinical trials. How did the same groups who were once (and often still are) the strongest supporters of stem cell research become stem cell tourists? And how can scientists, clinicians, and regulators work to bring stem cell patients back home to the US and into the clinical trial process? In this paper, we argue that the continued marketing and use of experimental stem cell-based interventions is problematic and unsustainable. Central problems include the lack of patient protection, US liability standards, regulation of clinical sites, and clinician licensing. These interventions have insufficient evidence of safety and efficacy; patients may be wasting money and time, and they may be forgoing other opportunities for an intervention that has not been shown to be safe and effective. Current practices do not contribute to scientific progress because the data from the procedures are unsuitable for follow-up research to measure outcomes. In addition, there is no assurance for patients that they are receiving the interventions promised or of what dosage they are receiving. Furthermore, there is inconsistent or non-existent follow-up care. Public policy should be developed to correct the current situation. The current landscape of stem cell tourism should prompt a re-evaluation of current approaches to study cell-based interventions with respect to the design, initiation, and conduct of US clinical trials. Stakeholders, including scientists, clinicians, regulators and patient advocates, need to work together to find a compromise to keep patients in the US and within the clinical trial process. Using HIV/AIDS and breast cancer advocate cases as examples, we identify key priorities and goals for this policy effort.

Derivation of porcine pluripotent stem cells for biomedical research.

PubMed

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

2016-07-01

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

Congenital anomalies

PubMed Central

Kunisaki, Shaun M.

2012-01-01

Over the past decade, amniotic fluid-derived stem cells have emerged as a novel, experimental approach for the treatment of a wide variety of congenital anomalies diagnosed either in utero or postnatally. There are a number of unique properties of amniotic fluid stem cells that have allowed it to become a major research focus. These include the relative ease of accessing amniotic fluid cells in a minimally invasive fashion by amniocentesis as well as the relatively rich population of progenitor cells obtained from a small aliquot of fluid. Mesenchymal stem cells, c-kit positive stem cells, as well as induced pluripotent stem cells have all been derived from human amniotic fluid in recent years. This article gives a pediatric surgeon’s perspective on amniotic fluid stem cell therapy for the management of congenital anomalies. The current status in the use of amniotic fluid-derived stem cells, particularly as they relate as substrates in tissue engineering-based applications, is described in various animal models. A roadmap for further study and eventual clinical application is also proposed. PMID:22986340

Epirubicin-Adsorbed Nanodiamonds Kill Chemoresistant Hepatic Cancer Stem Cells

PubMed Central

2015-01-01

Chemoresistance is a primary cause of treatment failure in cancer and a common property of tumor-initiating cancer stem cells. Overcoming mechanisms of chemoresistance, particularly in cancer stem cells, can markedly enhance cancer therapy and prevent recurrence and metastasis. This study demonstrates that the delivery of Epirubicin by nanodiamonds is a highly effective nanomedicine-based approach to overcoming chemoresistance in hepatic cancer stem cells. The potent physical adsorption of Epirubicin to nanodiamonds creates a rapidly synthesized and stable nanodiamond–drug complex that promotes endocytic uptake and enhanced tumor cell retention. These attributes mediate the effective killing of both cancer stem cells and noncancer stem cells in vitro and in vivo. Enhanced treatment of both tumor cell populations results in an improved impairment of secondary tumor formation in vivo compared with treatment by unmodified chemotherapeutics. On the basis of these results, nanodiamond-mediated drug delivery may serve as a powerful method for overcoming chemoresistance in cancer stem cells and markedly improving overall treatment against hepatic cancers. PMID:25437772

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.

Ocular stem cells: a status update!

PubMed Central

2014-01-01

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

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.

Development of an in vitro culture method for stepwise differentiation of mouse embryonic stem cells and induced pluripotent stem cells into mature osteoclasts.

PubMed

Nishikawa, Keizo; Iwamoto, Yoriko; Ishii, Masaru

2014-05-01

The development of methods for differentiation of embryonic stem cells (ESCs) and induced pluripotent stem cell (iPSCs) into functional cells have helped to analyze the mechanism regulating cellular processes and to explore cell-based assays for drug discovery. Although several reports have demonstrated methods for differentiation of mouse ESCs into osteoclast-like cells, it remains unclear whether these methods are applicable for differentiation of iPSCs to osteoclasts. In this study, we developed a simple method for stepwise differentiation of mouse ESCs and iPSCs into bone-resorbing osteoclasts based upon a monoculture approach consisting of three steps. First, based on conventional hanging-drop methods, embryoid bodies (EBs) were produced from mouse ESCs or iPSCs. Second, EBs were cultured in medium supplemented with macrophage colony-stimulating factor (M-CSF), and differentiated to osteoclast precursors, which expressed CD11b. Finally, ESC- or iPSC-derived osteoclast precursors stimulated with receptor activator of nuclear factor-B ligand (RANKL) and M-CSF formed large multinucleated osteoclast-like cells that expressed tartrate-resistant acid phosphatase and were capable of bone resorption. Molecular analysis showed that the expression of osteoclast marker genes such as Nfatc1, Ctsk, and Acp5 are increased in a RANKL-dependent manner. Thus, our procedure is simple and easy and would be helpful for stem cell-based bone research.

Drosophila Glypicans Regulate Follicle Stem Cell Maintenance and Niche Competition.

PubMed

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

2018-04-09

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

Hydrogel Encapsulation Facilitates Rapid-Cooling Cryopreservation of Stem Cell-Laden Core-Shell Microcapsules as Cell-Biomaterial Constructs.

PubMed

Zhao, Gang; Liu, Xiaoli; Zhu, Kaixuan; He, Xiaoming

2017-12-01

Core-shell structured stem cell microencapsulation in hydrogel has wide applications in tissue engineering, regenerative medicine, and cell-based therapies because it offers an ideal immunoisolative microenvironment for cell delivery and 3D culture. Long-term storage of such microcapsules as cell-biomaterial constructs by cryopreservation is an enabling technology for their wide distribution and ready availability for clinical transplantation. However, most of the existing studies focus on cryopreservation of single cells or cells in microcapsules without a core-shell structure (i.e., hydrogel beads). The goal of this study is to achieve cryopreservation of stem cells encapsulated in core-shell microcapsules as cell-biomaterial constructs or biocomposites. To this end, a capillary microfluidics-based core-shell alginate hydrogel encapsulation technology is developed to produce porcine adipose-derived stem cell-laden microcapsules for vitreous cryopreservation with very low concentration (2 mol L -1 ) of cell membrane penetrating cryoprotective agents (CPAs) by suppressing ice formation. This may provide a low-CPA and cost-effective approach for vitreous cryopreservation of "ready-to-use" stem cell-biomaterial constructs, facilitating their off-the-shelf availability and widespread applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

PubMed

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

2018-06-01

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

Labeling and Imaging Mesenchymal Stem Cells with Quantum Dots

EPA Science Inventory

Mesenchymal stem cells (MSCs) are multipotent cells with the potential to differentiate into bone, cartilage, adipose and muscle cells. Adult derived MSCs are being actively investigated because of their potential to be utilized for therapeutic cell-based transplantation. Methods...

Bioreactor Engineering of Stem Cell Environments

PubMed Central

Tandon, Nina; Marolt, Darja; Cimetta, Elisa; Vunjak-Novakovic, Gordana

2013-01-01

Stem cells hold promise to revolutionize modern medicine by development of new therapies, disease models and drug screening systems. Standard cell culture systems have limited biological relevance because they do not recapitulate the complex 3-dimensional interactions and biophysical cues that characterize the in vivo environment. In this review, we discuss the current advances in engineering stem cell environments using novel biomaterials and bioreactor technologies. We also reflect on the challenges the field is currently facing with regard to translation of stem cell based therapies into the clinic. PMID:23531529

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

PubMed

Weston, Nicole M; Sun, Dong

2018-01-25

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

Regulated and Unregulated Clinical Trials of Stem Cell Therapies for Stroke

PubMed Central

Liska, Michael G.; Crowley, Marci G.; Borlongan, Cesar V.

2017-01-01

Several lines of laboratory investigations reporting solid safety profiles and robust efficacy readouts of stem cells in clinically relevant animal models have advanced stem cell transplantation as an experimental therapy for stroke. Unfortunately, translating laboratory findings into effective clinical trials entails rigorous regulatory examinations, which posed a major challenge in the application of stem cells to patients. As a consequence of this slow pace of clinical entry, and a media-propagated hype narrating stem cells as a “magic bullet”, a dangerous market has been created for unregulated stem cell clinics. These clinics are often guilty of misleading patients and delivering low-quality, even harmful, treatments. Additionally, these medical tourism-purported clinical procedures, which have been performed even in the US, are likely to negatively impact on the true science and clinical value of stem cells. For the full potential of stem cell therapies to be realized, these pressing public misconceptions and regulatory clinical concerns must be addressed. Here, we provide the scientific evidence supporting the safe and effective conduct of stem cells. Arguably, relying on such evidence-based science to dictate the translation of stem cells from the laboratory to the clinic should allow an objective assessment of the risks and the rewards, and the delineation of the hype from hope of this experimental stroke therapy. PMID:28127687

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

PubMed

Beane, Olivia S; Darling, Eric M

2012-10-01

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

Optimized Delivery System Achieves Enhanced Endomyocardial Stem Cell Retention

PubMed Central

Behfar, Atta; Latere, Jean-Pierre; Bartunek, Jozef; Homsy, Christian; Daro, Dorothee; Crespo-Diaz, Ruben J.; Stalboerger, Paul G.; Steenwinckel, Valerie; Seron, Aymeric; Redfield, Margaret M.; Terzic, Andre

2014-01-01

Background Regenerative cell-based therapies are associated with limited myocardial retention of delivered stem cells. The objective of this study is to develop an endocardial delivery system for enhanced cell retention. Methods and Results Stem cell retention was simulated in silico using one and three-dimensional models of tissue distortion and compliance associated with delivery. Needle designs, predicted to be optimal, were accordingly engineered using nitinol – a nickel and titanium alloy displaying shape memory and super-elasticity. Biocompatibility was tested with human mesenchymal stem cells. Experimental validation was performed with species-matched cells directly delivered into Langendorff-perfused porcine hearts or administered percutaneously into the endocardium of infarcted pigs. Cell retention was quantified by flow cytometry and real time quantitative polymerase chain reaction methodology. Models, computing optimal distribution of distortion calibrated to favor tissue compliance, predicted that a 75°-curved needle featuring small-to-large graded side holes would ensure the highest cell retention profile. In isolated hearts, the nitinol curved needle catheter (C-Cath) design ensured 3-fold superior stem cell retention compared to a standard needle. In the setting of chronic infarction, percutaneous delivery of stem cells with C-Cath yielded a 37.7±7.1% versus 10.0±2.8% retention achieved with a traditional needle, without impact on biocompatibility or safety. Conclusions Modeling guided development of a nitinol-based curved needle delivery system with incremental side holes achieved enhanced myocardial stem cell retention. PMID:24326777

Neural and mesenchymal stem cells in animal models of Huntington's disease: past experiences and future challenges.

PubMed

Kerkis, Irina; Haddad, Monica Santoro; Valverde, Cristiane Wenceslau; Glosman, Sabina

2015-12-14

Huntington's disease (HD) is an inherited disease that causes progressive nerve cell degeneration. It is triggered by a mutation in the HTT gene that strongly influences functional abilities and usually results in movement, cognitive and psychiatric disorders. HD is incurable, although treatments are available to help manage symptoms and to delay the physical, mental and behavioral declines associated with the condition. Stem cells are the essential building blocks of life, and play a crucial role in the genesis and development of all higher organisms. Ablative surgical procedures and fetal tissue cell transplantation, which are still experimental, demonstrate low rates of recovery in HD patients. Due to neuronal cell death caused by accumulation of the mutated huntingtin (mHTT) protein, it is unlikely that such brain damage can be treated solely by drug-based therapies. Stem cell-based therapies are important in order to reconstruct damaged brain areas in HD patients. These therapies have a dual role: stem cell paracrine action, stimulating local cell survival, and brain tissue regeneration through the production of new neurons from the intrinsic and likely from donor stem cells. This review summarizes current knowledge on neural stem/progenitor cell and mesenchymal stem cell transplantation, which has been carried out in several animal models of HD, discussing cell distribution, survival and differentiation after transplantation, as well as functional recovery and anatomic improvements associated with these approaches. We also discuss the usefulness of this information for future preclinical and clinical studies in HD.

Imperative role of dental pulp stem cells in regenerative therapies: a systematic review.

PubMed

Kabir, Ramchandra; Gupta, Manish; Aggarwal, Avanti; Sharma, Deepak; Sarin, Anurag; Kola, Mohammed Zaheer

2014-01-01

Stem cells are primitive cells that can differentiate and regenerate organs in different parts of the body such as heart, bones, muscles and nervous system. This has been a field of great clinical interest with immense possibilities of using the stem cells in regeneration of human organ those are damaged due to disease, developmental defects and accident. The knowledge of stem cell technology is increasing quickly in all medical specialties and in dental field too. Stem cells of dental origin appears to hold the key to various cell-based therapies in regenerative medicine, but most avenues are in experimental stages and many procedures are undergoing standardization and validation. Long-term preservation of SHED cells or DPSC is becoming a popular consideration, similar to the banking of umbilical cord blood. Dental pulp stem cells (DPSCs) are the adult multipotent cells that reside in the cell rich zone of the dental pulp. The multipotent nature of these DPSCs may be utilized in both dental and medical applications. A systematic review of the literature was performed using various internet based search engines (PubMed, Medline Plus, Cochrane, Medknow, Ebsco, Science Direct, Hinari, WebMD, IndMed, Embase) using keywords like "dental pulp stem cells", "regeneration", "medical applications", "tissue engineering". DPSCs appears to be a promising innovation for the re-growth of tissues however, long term clinical studies need to be carried out that could establish some authentic guidelines in this perspective.

Adult Human Nasal Mesenchymal-Like Stem Cells Restore Cochlear Spiral Ganglion Neurons After Experimental Lesion

PubMed Central

Bas, Esperanza; Van De Water, Thomas R.; Lumbreras, Vicente; Rajguru, Suhrud; Goss, Garrett; Hare, Joshua M.

2014-01-01

A loss of sensory hair cells or spiral ganglion neurons from the inner ear causes deafness, affecting millions of people. Currently, there is no effective therapy to repair the inner ear sensory structures in humans. Cochlear implantation can restore input, but only if auditory neurons remain intact. Efforts to develop stem cell-based treatments for deafness have demonstrated progress, most notably utilizing embryonic-derived cells. In an effort to bypass limitations of embryonic or induced pluripotent stem cells that may impede the translation to clinical applications, we sought to utilize an alternative cell source. Here, we show that adult human mesenchymal-like stem cells (MSCs) obtained from nasal tissue can repair spiral ganglion loss in experimentally lesioned cochlear cultures from neonatal rats. Stem cells engraft into gentamicin-lesioned organotypic cultures and orchestrate the restoration of the spiral ganglion neuronal population, involving both direct neuronal differentiation and secondary effects on endogenous cells. As a physiologic assay, nasal MSC-derived cells engrafted into lesioned spiral ganglia demonstrate responses to infrared laser stimulus that are consistent with those typical of excitable cells. The addition of a pharmacologic activator of the canonical Wnt/β-catenin pathway concurrent with stem cell treatment promoted robust neuronal differentiation. The availability of an effective adult autologous cell source for inner ear tissue repair should contribute to efforts to translate cell-based strategies to the clinic. PMID:24172073

Enhanced Stem Cell Differentiation and Immunopurification of Genome Engineered Human Retinal Ganglion Cells.

PubMed

Sluch, Valentin M; Chamling, Xitiz; Liu, Melissa M; Berlinicke, Cynthia A; Cheng, Jie; Mitchell, Katherine L; Welsbie, Derek S; Zack, Donald J

2017-11-01

Human pluripotent stem cells have the potential to promote biological studies and accelerate drug discovery efforts by making possible direct experimentation on a variety of human cell types of interest. However, stem cell cultures are generally heterogeneous and efficient differentiation and purification protocols are often lacking. Here, we describe the generation of clustered regularly-interspaced short palindromic repeats(CRISPR)-Cas9 engineered reporter knock-in embryonic stem cell lines in which tdTomato and a unique cell-surface protein, THY1.2, are expressed under the control of the retinal ganglion cell (RGC)-enriched gene BRN3B. Using these reporter cell lines, we greatly improved adherent stem cell differentiation to the RGC lineage by optimizing a novel combination of small molecules and established an anti-THY1.2-based protocol that allows for large-scale RGC immunopurification. RNA-sequencing confirmed the similarity of the stem cell-derived RGCs to their endogenous human counterparts. Additionally, we developed an in vitro axonal injury model suitable for studying signaling pathways and mechanisms of human RGC cell death and for high-throughput screening for neuroprotective compounds. Using this system in combination with RNAi-based knockdown, we show that knockdown of dual leucine kinase (DLK) promotes survival of human RGCs, expanding to the human system prior reports that DLK inhibition is neuroprotective for murine RGCs. These improvements will facilitate the development and use of large-scale experimental paradigms that require numbers of pure RGCs that were not previously obtainable. Stem Cells Translational Medicine 2017;6:1972-1986. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

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

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

Whittaker, Peter A.

A brief outline of stem cells, stem cell therapy and therapeutic cloning is given. The position of therapeutic cloning with regard to other embryonic manipulations - IVF-based reproduction, embryonic stem formation from IVF embryos and reproductive cloning - is indicated. The main ethically challenging stages in therapeutic cloning are considered to be the nuclear transfer process including the source of eggs for this and the destruction of an embryo to provide stem cells for therapeutic use. The extremely polarised nature of the debate regarding the status of an early human embryo is noted, and some potential alternative strategies for preparingmore » immunocompatible pluripotent stem cells are indicated.« less

Mechanical regulation of chondrogenesis

PubMed Central

2013-01-01

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

Metaplastic Cells in the Stomach Arise, Independently of Stem Cells, via Dedifferentiation or Transdifferentiation of Chief Cells.

PubMed

Radyk, Megan D; Burclaff, Joseph; Willet, Spencer G; Mills, Jason C

2018-03-01

Spasmolytic polypeptide-expressing metaplasia (SPEM) develops in patients with chronic atrophic gastritis due to infection with Helicobacter pylori; it might be a precursor to intestinal metaplasia and gastric adenocarcinoma. Lineage tracing experiments of the gastric corpus in mice have not established whether SPEM derives from proliferating stem cells or differentiated, post-mitotic zymogenic chief cells in the gland base. We investigated whether differentiated cells can give rise to SPEM using a nongenetic approach in mice. Mice were given intraperitoneal injections of 5-fluorouracil, which blocked gastric cell proliferation, plus tamoxifen to induce SPEM. Based on analyses of molecular and histologic markers, we found SPEM developed even in the absence of cell proliferation. SPEM therefore did not arise from stem cells. In histologic analyses of gastric resection specimens from 10 patients with adenocarcinoma, we found normal zymogenic chief cells that were transitioning into SPEM cells only in gland bases, rather than the proliferative stem cell zone. Our findings indicate that SPEM can arise by direct reprogramming of existing cells-mainly of chief cells. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

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.

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

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.

An "age"-structured model of hematopoietic stem cell organization with application to chronic myeloid leukemia.

PubMed

Roeder, Ingo; Herberg, Maria; Horn, Matthias

2009-04-01

Previously, we have modeled hematopoietic stem cell organization by a stochastic, single cell-based approach. Applications to different experimental systems demonstrated that this model consistently explains a broad variety of in vivo and in vitro data. A major advantage of the agent-based model (ABM) is the representation of heterogeneity within the hematopoietic stem cell population. However, this advantage comes at the price of time-consuming simulations if the systems become large. One example in this respect is the modeling of disease and treatment dynamics in patients with chronic myeloid leukemia (CML), where the realistic number of individual cells to be considered exceeds 10(6). To overcome this deficiency, without losing the representation of the inherent heterogeneity of the stem cell population, we here propose to approximate the ABM by a system of partial differential equations (PDEs). The major benefit of such an approach is its independence from the size of the system. Although this mean field approach includes a number of simplifying assumptions compared to the ABM, it retains the key structure of the model including the "age"-structure of stem cells. We show that the PDE model qualitatively and quantitatively reproduces the results of the agent-based approach.

Attitude of A Sample of Iranian Researchers toward The Future of Stem Cell Research.

PubMed

Lotfipanah, Mahdi; Azadeh, Fereydoon; Totonchi, Mehdi; Omani-Samani, Reza

2018-10-01

Stem cells that have unlimited proliferation potential as well as differentiation potency are considered to be a promising future treatment method for incurable diseases. The aim of the present study is to evaluate the future trend of stem cell researches from researchers' viewpoints. This was a cross-sectional descriptive study on researchers involved in stem cell research at Royan Institute. We designed a questionnaire using a qualitative study based on expert opinion and a literature review. Content validity was performed using three rounds of the Delphi method with experts. Face validity was undertaken by a Persian literature expert and a graphics designer. The questionnaire was distributed among 150 researchers involved in stem cell studies in Royan Institute biology laboratories. We collected 138 completed questionnaires. The mean age of participants was 31.13 ± 5.8 years; most (60.9%) were females. Participants (76.1%) considered the budget to be the most important issue in stem cell research, 79.7% needed financial support from the government, and 77.5% felt that charities could contribute substantially to stem cell research. A total of 90.6% of participants stated that stem cells should lead to commercial usage which could support future researches (86.2%). The aim of stem cell research was stipulated as increasing health status of the society according to 92.8% of the participants. At present, among cell types, importance was attached to cord blood and adult stem cells. Researchers emphasized the importance of mesenchymal stem cells (MSCs) rather than hematopoietic stem cells (HSCs, 57.73%). The prime priorities were given to cancer so that stem cell research could be directed to sphere stem cell research whereas the least preference was given to skin research. Regenerative medicine is considered the future of stem cell research with emphasis on application of these cells, especially in cancer treatment. Copyright© by Royan Institute. All rights reserved.

Cell-based therapeutic strategies for multiple sclerosis

PubMed Central

Scolding, Neil J; Pasquini, Marcelo; Reingold, Stephen C; Cohen, Jeffrey A; Atkins, Harold; Banwell, Brenda; Bar-Or, Amit; Bebo, Bruce; Bowen, James; Burt, Richard; Calabresi, Peter; Cohen, Jeffrey; Comi, Giancarlo; Connick, Peter; Cross, Anne; Cutter, Gary; Derfuss, Tobias; Ffrench-Constant, Charles; Freedman, Mark; Galipeau, Jacques; Goldman, Myla; Goldman, Steven; Goodman, Andrew; Green, Ari; Griffith, Linda; Hartung, Hans-Peter; Hemmer, Bernhard; Hyun, Insoo; Iacobaeus, Ellen; Inglese, Matilde; Jubelt, Burk; Karussis, Dimitrios; Küry, Patrick; Landsman, Douglas; Laule, Cornelia; Liblau, Roland; Mancardi, Giovanni; Ann Marrie, Ruth; Miller, Aaron; Miller, Robert; Miller, David; Mowry, Ellen; Muraro, Paolo; Nash, Richard; Ontaneda, Daniel; Pasquini, Marcelo; Pelletier, Daniel; Peruzzotti-Jametti, Luca; Pluchino, Stefano; Racke, Michael; Reingold, Stephen; Rice, Claire; Ringdén, Olle; Rovira, Alex; Saccardi, Riccardo; Sadiq, Saud; Sarantopoulos, Stefanie; Savitz, Sean; Scolding, Neil; Soelberg Sorensen, Per; Pia Sormani, Maria; Stuve, Olaf; Tesar, Paul; Thompson, Alan; Trojano, Maria; Uccelli, Antonio; Uitdehaag, Bernard; Utz, Ursula; Vukusic, Sandra; Waubant, Emmanuelle; Wilkins, Alastair

2017-01-01

Abstract The availability of multiple disease-modifying medications with regulatory approval to treat multiple sclerosis illustrates the substantial progress made in therapy of the disease. However, all are only partially effective in preventing inflammatory tissue damage in the central nervous system and none directly promotes repair. Cell-based therapies, including immunoablation followed by autologous haematopoietic stem cell transplantation, mesenchymal and related stem cell transplantation, pharmacologic manipulation of endogenous stem cells to enhance their reparative capabilities, and transplantation of oligodendrocyte progenitor cells, have generated substantial interest as novel therapeutic strategies for immune modulation, neuroprotection, or repair of the damaged central nervous system in multiple sclerosis. Each approach has potential advantages but also safety concerns and unresolved questions. Moreover, clinical trials of cell-based therapies present several unique methodological and ethical issues. We summarize here the status of cell-based therapies to treat multiple sclerosis and make consensus recommendations for future research and clinical trials. PMID:29053779

Key action items for the stem cell field: looking ahead to 2014.

PubMed

Knoepfler, Paul S

2013-12-01

The stem cell field is at a critical juncture in late 2013. We find ourselves buoyed by building momentum for both transformative basic science discoveries and clinical translation of stem cells. Cellular reprogramming has given the field exciting new avenues as well. The overall prospect of novel stem cell-based therapies becoming a reality for patients in the coming years has never seemed higher. At the same time, we face serious challenges. Some of these challenges, such as stem cell tourism, are familiar to us, although even those are evolving in ways that require adaptability and action by the stem cell field. Other new challenges are also emerging, including an urgent need for formal physician training in stem cells, regulatory compliance balanced with innovation and U.S. Food and Drug Administration reform, and savvy educational outreach. Looking ahead to 2014, both the challenges and opportunities for the stem cell field require a proactive, thoughtful approach to maximize the potential for a positive impact from stem cell advances. In this study, I discuss the key action items for the field as we look ahead to the coming year and beyond.

Adipogenic placenta-derived mesenchymal stem cells are not lineage restricted by withdrawing extrinsic factors: developing a novel visual angle in stem cell biology.

PubMed

Hu, C; Cao, H; Pan, X; Li, J; He, J; Pan, Q; Xin, J; Yu, X; Li, J; Wang, Y; Zhu, D; Li, L

2016-03-17

Current evidence implies that differentiated bone marrow mesenchymal stem cells (BMMSCs) can act as progenitor cells and transdifferentiate across lineage boundaries. However, whether this unrestricted lineage has specificities depending on the stem cell type is unknown. Placental-derived mesenchymal stem cells (PDMSCs), an easily accessible and less invasive source, are extremely useful materials in current stem cell therapies. No studies have comprehensively analyzed the transition in morphology, surface antigens, metabolism and multilineage potency of differentiated PDMSCs after their dedifferentiation. In this study, we showed that after withdrawing extrinsic factors, adipogenic PDMSCs reverted to a primitive cell population and retained stem cell characteristics. The mitochondrial network during differentiation and dedifferentiation may serve as a marker of absent or acquired pluripotency in various stem cell models. The new population proliferated faster than unmanipulated PDMSCs and could be differentiated into adipocytes, osteocytes and hepatocytes. The cell adhesion molecules (CAMs) signaling pathway and extracellular matrix (ECM) components modulate cell behavior and enable the cells to proliferate or differentiate during the differentiation, dedifferentiation and redifferentiation processes in our study. These observations indicate that the dedifferentiated PDMSCs are distinguishable from the original PDMSCs and may serve as a novel source in stem cell biology and cell-based therapeutic strategies. Furthermore, whether PDMSCs differentiated into other lineages can be dedifferentiated to a primitive cell population needs to be investigated.

Bone Marrow Stem Cells in Clinical Application: Harnessing Paracrine Roles and Niche Mechanisms

NASA Astrophysics Data System (ADS)

Backly, Rania M. El; Cancedda, Ranieri

The being of any individual throughout life is a dynamic process relying on the capacity to retain processes of self-renewal and differentiation, both of which are hallmarks of stem cells. Although limited in the adult human organism, regeneration and repair do take place in virtue of the presence of adult stem cells. In the bone marrow, two major populations of stem cells govern the dynamic equilibrium of both hemopoiesis and skeletal homeostasis; the hematopoietic and the mesenchymal stem cells. Recent cell based clinical trials utilizing bone marrow-derived stem cells as therapeutic agents have revealed promising results, while others have failed to display as such. It is therefore imperative to strive to understand the mechanisms by which these cells function in vivo, how their properties can be maintained ex-vivo, and to explore further their recently highlighted immunomodulatory and trophic effects.

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.

Cell fiber-based three-dimensional culture system for highly efficient expansion of human induced pluripotent stem cells.

PubMed

Ikeda, Kazuhiro; Nagata, Shogo; Okitsu, Teru; Takeuchi, Shoji

2017-06-06

Human pluripotent stem cells are a potentially powerful cellular resource for application in regenerative medicine. Because such applications require large numbers of human pluripotent stem cell-derived cells, a scalable culture system of human pluripotent stem cell needs to be developed. Several suspension culture systems for human pluripotent stem cell expansion exist; however, it is difficult to control the thickness of cell aggregations in these systems, leading to increased cell death likely caused by limited diffusion of gases and nutrients into the aggregations. Here, we describe a scalable culture system using the cell fiber technology for the expansion of human induced pluripotent stem (iPS) cells. The cells were encapsulated and cultured within the core region of core-shell hydrogel microfibers, resulting in the formation of rod-shaped or fiber-shaped cell aggregations with sustained thickness and high viability. By encapsulating the cells with type I collagen, we demonstrated a long-term culture of the cells by serial passaging at a high expansion rate (14-fold in four days) while retaining its pluripotency. Therefore, our culture system could be used for large-scale expansion of human pluripotent stem cells for use in regenerative medicine.

Multiparametric Phenotypic Screening System for Profiling Bioactive Compounds Using Human Fetal Hippocampal Neural Stem/Progenitor Cells.

PubMed

Tabata, Yoshikuni; Murai, Norio; Sasaki, Takeo; Taniguchi, Sachie; Suzuki, Shuichi; Yamazaki, Kazuto; Ito, Masashi

2015-10-01

Stem cell research has been progressing rapidly, contributing to regenerative biology and regenerative medicine. In this field, small-molecule compounds affecting stem cell proliferation/differentiation have been explored to understand stem cell biology and support regenerative medicine. In this study, we established a multiparametric screening system to detect bioactive compounds affecting the cell fate of human neural stem/progenitor cells (NSCs/NPCs), using human fetal hippocampal NSCs/NPCs, HIP-009 cells. We examined effects of 410 compounds, which were collected based on mechanisms of action (MOAs) and chemotypes, on HIP-009's cell fate (self-renewal, neuronal and astrocytic differentiation) and morphology by automated multiparametric assays and profiled induced cellular phenotypes. We found that this screening classified compounds with the same MOAs into subgroups according to additional pharmacological effects (e.g., mammalian target of rapamycin complex 1 [mTORC1] inhibitors and mTORC1/mTORC2 dual inhibitors among mTOR inhibitors). Moreover, it identified compounds that have off-target effects under matrix analyses of MOAs and structure similarities (e.g., neurotropic effects of amitriptyline among tri- and tetracyclic compounds). Therefore, this automated, medium-throughput and multiparametric screening system is useful for finding compounds that affect the cell fate of human NSCs/NPCs for supporting regenerative medicine and to fingerprint compounds based on human stem cells' multipotency, leading to understanding of stem cell biology. © 2015 Society for Laboratory Automation and Screening.

Imperative Role of Dental Pulp Stem Cells in Regenerative Therapies: A Systematic Review

PubMed Central

Kabir, Ramchandra; Gupta, Manish; Aggarwal, Avanti; Sharma, Deepak; Sarin, Anurag; Kola, Mohammed Zaheer

2014-01-01

Stem cells are primitive cells that can differentiate and regenerate organs in different parts of the body such as heart, bones, muscles and nervous system. This has been a field of great clinical interest with immense possibilities of using the stem cells in regeneration of human organ those are damaged due to disease, developmental defects and accident. The knowledge of stem cell technology is increasing quickly in all medical specialties and in dental field too. Stem cells of dental origin appears to hold the key to various cell-based therapies in regenerative medicine, but most avenues are in experimental stages and many procedures are undergoing standardization and validation. Long-term preservation of SHED cells or DPSC is becoming a popular consideration, similar to the banking of umbilical cord blood. Dental pulp stem cells (DPSCs) are the adult multipotent cells that reside in the cell rich zone of the dental pulp. The multipotent nature of these DPSCs may be utilized in both dental and medical applications. A systematic review of the literature was performed using various internet based search engines (PubMed, Medline Plus, Cochrane, Medknow, Ebsco, Science Direct, Hinari, WebMD, IndMed, Embase) using keywords like “dental pulp stem cells”, “regeneration”, “medical applications”, “tissue engineering”. DPSCs appears to be a promising innovation for the re-growth of tissues however, long term clinical studies need to be carried out that could establish some authentic guidelines in this perspective. PMID:24665194

Stem cells in reproductive medicine: ready for the patient?

PubMed

Vassena, R; Eguizabal, C; Heindryckx, B; Sermon, K; Simon, C; van Pelt, A M M; Veiga, A; Zambelli, F

2015-09-01

Are there effective and clinically validated stem cell-based therapies for reproductive diseases? At the moment, clinically validated stem cell treatments for reproductive diseases and alterations are not available. Research in stem cells and regenerative medicine is growing in scope, and its translation to the clinic is heralded by the recent initiation of controlled clinical trials with pluripotent derived cells. Unfortunately, stem cell 'treatments' are currently offered to patients outside of the controlled framework of scientifically sound research and regulated clinical trials. Both physicians and patients in reproductive medicine are often unsure about stem cells therapeutic options. An international working group was assembled to review critically the available scientific literature in both the human species and animal models. This review includes work published in English until December 2014, and available through Pubmed. A few areas of research in stem cell and reproductive medicine were identified: in vitro gamete production, endometrial regeneration, erectile dysfunction amelioration, vaginal reconstruction. The stem cells studied range from pluripotent (embryonic stem cells and induced pluripotent stem cells) to monopotent stem cells, such as spermatogonial stem cells or mesenchymal stem cells. The vast majority of studies have been carried out in animal models, with data that are preliminary at best. This review was not conducted in a systematic fashion, and reports in publications not indexed in Pubmed were not analyzed. A much broader clinical knowledge will have to be acquired before translation to the clinic of stem cell therapies in reproductive medicine; patients and physicians should be wary of unfounded claims of improvement of existing medical conditions; at the moment, effective stem cell treatment for reproductive diseases and alterations is not available. None. NA. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

Electrical Stimulation Followed by Mesenchymal Stem Cells Improves Anal Sphincter Anatomy and Function in a Rat Model at a Time Remote From Injury.

PubMed

Sun, Li; Yeh, Judy; Xie, Zhuojun; Kuang, Mei; Damaser, Margot S; Zutshi, Massarat

2016-05-01

We have explored cell-based therapy to aid anal sphincter repair, but a conditioning injury is required to direct stem cells to the site of injury because symptoms usually manifest at a time remote from injury. We aimed to investigate the effect of local electrical stimulation followed by mesenchymal stem cell delivery on anal sphincter regeneration at a time remote from injury. With the use of a rat model, electrical stimulation parameters and cell delivery route were selected based on in vivo cytokine expression and luciferase-labeled cell imaging of the anal sphincter complex. Three weeks after a partial anal sphincter excision, rats were randomly allocated to 4 groups based on different local interventions: no treatment, daily electrical stimulation for 3 days, daily stimulation for 3 days followed by stem cell injection on the third day, and daily electrical stimulation followed by stem cell injection on the first and third days. Histology-assessed anatomy and anal manometry evaluated physiology 4 weeks after intervention. The electrical stimulation parameters that significantly upregulated gene expression of homing cytokines also achieved mesenchymal stem cell retention when injected directly in the anal sphincter complex in comparison with intravascular and intraperitoneal injections. Four weeks after intervention, there was significantly more new muscle in the area of injury and significantly improved anal resting pressure in the group that received daily electrical stimulation for 3 days followed by a single injection of 1 million stem cells on the third day at the site of injury. This was a pilot study and therefore was not powered for functional outcome. In this rat injury model with optimized parameters, electrical stimulation with a single local mesenchymal stem cell injection administered 3 weeks after injury significantly improved both new muscle formation in the area of injury and anal sphincter pressures.

Stem-cell-activated organ following ultrasound exposure: better transplant option for organ transplantation.

PubMed

Wang, Sen; Li, Yu; Ji, Ying-Chang; Lin, Chang-Min; Man, Cheng; Zheng, Xiao-Xuan

2010-01-01

Although doctors try their best to protect transplants during surgery, there remain great challenges for the higher survival rate and less rejection of transplants after organ transplantation. Growing evidence indicates that the stem cells could function after injury rather than aging, implying that suitable injury may activate the stem cells of damaged organs. Furthermore, it has been revealed that stem cells can be used to induce tolerance in transplantation and the ultrasound has great biological effects on organs. Basing on these facts, we hypothesize that the stem cells within the transplants can be activated by ultrasound with high-frequency and medium-intensity. Therefore, the stem-cell-activated organs (SCAO) can be derived, and the SCAO will be better transplant option for organ transplantation. We postulate the ultrasound can change the molecular activity and/or quantity of the stem cells, the membrane permeability, the cell-cell junctions, and their surrounding microenvironments. As a result, the stem cells are activated, and the SCAO will acquire more regenerative capacity and less rejection. In the paper, we also discuss the process, methods and models for verifying the theory, and the consequences. We believe the theory may provide a practical method for the clinical application of the ultrasound and stem cells in organ transplantation.

Priming of the Cells: Hypoxic Preconditioning for Stem Cell Therapy

PubMed Central

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

2017-01-01

Objective: Stem cell-based therapies are promising in regenerative medicine for protecting and repairing damaged brain tissues after injury or in the context of chronic diseases. Hypoxia can induce physiological and pathological responses. A hypoxic insult might act as a double-edged sword, it induces cell death and brain damage, but on the other hand, sublethal hypoxia can trigger an adaptation response called hypoxic preconditioning or hypoxic tolerance that is of immense importance for the survival of cells and tissues. Data Sources: This review was based on articles published in PubMed databases up to August 16, 2017, with the following keywords: “stem cells,” “hypoxic preconditioning,” “ischemic preconditioning,” and “cell transplantation.” Study Selection: Original articles and critical reviews on the topics were selected. Results: Hypoxic preconditioning has been investigated as a primary endogenous protective mechanism and possible treatment against ischemic injuries. Many cellular and molecular mechanisms underlying the protective effects of hypoxic preconditioning have been identified. Conclusions: In cell transplantation therapy, hypoxic pretreatment of stem cells and neural progenitors markedly increases the survival and regenerative capabilities of these cells in the host environment, leading to enhanced therapeutic effects in various disease models. Regenerative treatments can mobilize endogenous stem cells for neurogenesis and angiogenesis in the adult brain. Furthermore, transplantation of stem cells/neural progenitors achieves therapeutic benefits via cell replacement and/or increased trophic support. Combinatorial approaches of cell-based therapy with additional strategies such as neuroprotective protocols, anti-inflammatory treatment, and rehabilitation therapy can significantly improve therapeutic benefits. In this review, we will discuss the recent progress regarding cell types and applications in regenerative medicine as well as future applications. PMID:28937044

Small Molecule Protection of Bone Marrow Hematopoietic Stem Cells

DTIC Science & Technology

2015-10-01

several recently identified small molecules can protect hematopoietic stem cells (HSCs) from damage or killing by endogenous aldehydes . Proof-of-concept...anemia bone marrow failure CD34+ hematopoietic stem cells aldehydes formaldehyde DNA damage DNA base adduct DNA-protein crosslink mass...below. Revised Specific Aim 1: Small molecule protection of human cells from aldehyde - induced killing (in vitro studies - no mice or human subjects

Prion diseases and adult neurogenesis: how do prions counteract the brain's endogenous repair machinery?

PubMed

Relaño-Ginés, Aroa; Lehmann, Sylvain; Crozet, Carole

2014-01-01

Scientific advances in stem cell biology and adult neurogenesis have raised the hope that neurodegenerative disorders could benefit from stem cell-based therapy. Adult neurogenesis might be part of the physiological regenerative process, however it might become impaired by the disease's mechanism and therefore contribute to neurodegeneration. In prion disorders this endogenous repair system has rarely been studied. Whether adult neurogenesis plays a role or not in brain repair or in the propagation of prion pathology remains unclear. We have recently investigated the status of adult neural stem cells isolated from prion-infected mice. We were able to show that neural stem cells accumulate and replicate prions thus resulting in an alteration of their neuronal destiny. We also reproduced these results in adult neural stem cells, which were infected in vitro. The fact that endogenous adult neurogenesis could be altered by the accumulation of misfolded prion protein represents another great challenge. Inhibiting prion propagation in these cells would thus help the endogenous neurogenesis to compensate for the injured neuronal system. Moreover, understanding the endogenous modulation of the neurogenesis system would help develop effective neural stem cell-based therapies.

Pipette-based Method to Study Embryoid Body Formation Derived from Mouse and Human Pluripotent Stem Cells Partially Recapitulating Early Embryonic Development Under Simulated Microgravity Conditions

NASA Astrophysics Data System (ADS)

Shinde, Vaibhav; Brungs, Sonja; Hescheler, Jürgen; Hemmersbach, Ruth; Sachinidis, Agapios

2016-06-01

The in vitro differentiation of pluripotent stem cells partially recapitulates early in vivo embryonic development. More recently, embryonic development under the influence of microgravity has become a primary focus of space life sciences. In order to integrate the technique of pluripotent stem cell differentiation with simulated microgravity approaches, the 2-D clinostat compatible pipette-based method was experimentally investigated and adapted for investigating stem cell differentiation processes under simulated microgravity conditions. In order to keep residual accelerations as low as possible during clinorotation, while also guaranteeing enough material for further analysis, stem cells were exposed in 1-mL pipettes with a diameter of 3.5 mm. The differentiation of mouse and human pluripotent stem cells inside the pipettes resulted in the formation of embryoid bodies at normal gravity (1 g) after 24 h and 3 days. Differentiation of the mouse pluripotent stem cells on a 2-D pipette-clinostat for 3 days also resulted in the formation of embryoid bodies. Interestingly, the expression of myosin heavy chain was downregulated when cultivation was continued for an additional 7 days at normal gravity. This paper describes the techniques for culturing and differentiation of pluripotent stem cells and exposure to simulated microgravity during culturing or differentiation on a 2-D pipette clinostat. The implementation of these methodologies along with -omics technologies will contribute to understand the mechanisms regulating how microgravity influences early embryonic development.

Stem cell bioprocessing: fundamentals and principles

PubMed Central

Placzek, Mark R.; Chung, I-Ming; Macedo, Hugo M.; Ismail, Siti; Mortera Blanco, Teresa; Lim, Mayasari; Min Cha, Jae; Fauzi, Iliana; Kang, Yunyi; Yeo, David C.L.; Yip Joan Ma, Chi; Polak, Julia M.; Panoskaltsis, Nicki; Mantalaris, Athanasios

2008-01-01

In recent years, the potential of stem cell research for tissue engineering-based therapies and regenerative medicine clinical applications has become well established. In 2006, Chung pioneered the first entire organ transplant using adult stem cells and a scaffold for clinical evaluation. With this a new milestone was achieved, with seven patients with myelomeningocele receiving stem cell-derived bladder transplants resulting in substantial improvements in their quality of life. While a bladder is a relatively simple organ, the breakthrough highlights the incredible benefits that can be gained from the cross-disciplinary nature of tissue engineering and regenerative medicine (TERM) that encompasses stem cell research and stem cell bioprocessing. Unquestionably, the development of bioprocess technologies for the transfer of the current laboratory-based practice of stem cell tissue culture to the clinic as therapeutics necessitates the application of engineering principles and practices to achieve control, reproducibility, automation, validation and safety of the process and the product. The successful translation will require contributions from fundamental research (from developmental biology to the ‘omics’ technologies and advances in immunology) and from existing industrial practice (biologics), especially on automation, quality assurance and regulation. The timely development, integration and execution of various components will be critical—failures of the past (such as in the commercialization of skin equivalents) on marketing, pricing, production and advertising should not be repeated. This review aims to address the principles required for successful stem cell bioprocessing so that they can be applied deftly to clinical applications. PMID:19033137

Stem cell bioprocessing: fundamentals and principles.

PubMed

Placzek, Mark R; Chung, I-Ming; Macedo, Hugo M; Ismail, Siti; Mortera Blanco, Teresa; Lim, Mayasari; Cha, Jae Min; Fauzi, Iliana; Kang, Yunyi; Yeo, David C L; Ma, Chi Yip Joan; Polak, Julia M; Panoskaltsis, Nicki; Mantalaris, Athanasios

2009-03-06

In recent years, the potential of stem cell research for tissue engineering-based therapies and regenerative medicine clinical applications has become well established. In 2006, Chung pioneered the first entire organ transplant using adult stem cells and a scaffold for clinical evaluation. With this a new milestone was achieved, with seven patients with myelomeningocele receiving stem cell-derived bladder transplants resulting in substantial improvements in their quality of life. While a bladder is a relatively simple organ, the breakthrough highlights the incredible benefits that can be gained from the cross-disciplinary nature of tissue engineering and regenerative medicine (TERM) that encompasses stem cell research and stem cell bioprocessing. Unquestionably, the development of bioprocess technologies for the transfer of the current laboratory-based practice of stem cell tissue culture to the clinic as therapeutics necessitates the application of engineering principles and practices to achieve control, reproducibility, automation, validation and safety of the process and the product. The successful translation will require contributions from fundamental research (from developmental biology to the 'omics' technologies and advances in immunology) and from existing industrial practice (biologics), especially on automation, quality assurance and regulation. The timely development, integration and execution of various components will be critical-failures of the past (such as in the commercialization of skin equivalents) on marketing, pricing, production and advertising should not be repeated. This review aims to address the principles required for successful stem cell bioprocessing so that they can be applied deftly to clinical applications.

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

PubMed

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

2014-08-22

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

High incidence of non-random template strand segregation and asymmetric fate determination in dividing stem cells and their progeny.

PubMed

Conboy, Michael J; Karasov, Ariela O; Rando, Thomas A

2007-05-01

Decades ago, the "immortal strand hypothesis" was proposed as a means by which stem cells might limit acquiring mutations that could give rise to cancer, while continuing to proliferate for the life of an organism. Originally based on observations in embryonic cells, and later studied in terms of stem cell self-renewal, this hypothesis has remained largely unaccepted because of few additional reports, the rarity of the cells displaying template strand segregation, and alternative interpretations of experiments involving single labels or different types of labels to follow template strands. Using sequential pulses of halogenated thymidine analogs (bromodeoxyuridine [BrdU], chlorodeoxyuridine [CldU], and iododeoxyuridine [IdU]), and analyzing stem cell progeny during induced regeneration in vivo, we observed extraordinarily high frequencies of segregation of older and younger template strands during a period of proliferative expansion of muscle stem cells. Furthermore, template strand co-segregation was strongly associated with asymmetric cell divisions yielding daughters with divergent fates. Daughter cells inheriting the older templates retained the more immature phenotype, whereas daughters inheriting the newer templates acquired a more differentiated phenotype. These data provide compelling evidence of template strand co-segregation based on template age and associated with cell fate determination, suggest that template strand age is monitored during stem cell lineage progression, and raise important caveats for the interpretation of label-retaining cells.

Regulatory requirements in the good manufacturing practice production of an epithelial cell graft for ocular surface reconstruction.

PubMed

Sheth-Shah, Radhika; Vernon, Amanda J; Seetharaman, Shankar; Neale, Michael H; Daniels, Julie T

2016-04-01

In the past decade, stem cell therapy has been increasingly employed for the treatment of various diseases. Subsequently, there has been a great interest in the manufacture of stem cells under good manufacturing practice, which is required by law for their use in humans. The cells for sight Stem Cell Therapy Research Unit, based at UCL Institute of Ophthalmology, delivers somatic cell-based and tissue-engineered therapies to patients suffering from blinding eye diseases at Moorfields Eye Hospital (London, UK). The following article is based on our experience in the conception, design, construction, validation and manufacturing within a good manufacturing practice manufacturing facility based in the UK. As such the regulations can be extrapolated to the 28 members stated within the EU. However, the principles may have a broad relevance outside the EU.

Induced Pluripotent Stem Cells: A novel frontier in the study of human primary immunodeficiencies

PubMed Central

Pessach, Itai M.; Ordovas-Montanes, Jose; Zhang, Shen-Ying; Casanova, Jean-Laurent; Giliani, Silvia; Gennery, Andrew R.; Al-Herz, Waleed; Manos, Philip D.; Schlaeger, Thorsten M.; Park, In-Hyun; Rucci, Francesca; Agarwal, Suneet; Mostoslavsky, Gustavo; Daley, George Q.; Notarangelo, Luigi D.

2010-01-01

Background The novel ability to epigenetically reprogram somatic cells into induced pluripotent stem cells through the exogenous expression of transcription promises to revolutionize the study of human diseases. Objective Here we report on the generation of 25 induced pluripotent stem cell lines from 6 patients with various forms of Primary Immunodeficiencies, affecting adaptive and/or innate immunity. Methods Patients’ dermal fibroblasts were reprogrammed by expression of four transcription factors, OCT4, SOX2, KLF4, and c-MYC using a single excisable polycistronic lentiviral vector. Results Induced pluripotent stem cells derived from patients with primary immunodeficiencies show a stemness profile that is comparable to that observed in human embryonic stem cells. Following in vitro differentiation into embryoid bodies, pluripotency of the patient-derived indiced pluripotent stem cells lines was demonstrated by expression of genes characteristic of each of the three embryonic layers. We have confirmed the patient-specific origin of the induced pluripotent stem cell lines, and ascertained maintenance of karyotypic integrity. Conclusion By providing a limitless source of diseased stem cells that can be differentiated into various cell types in vitro, the repository of induced pluripotent stem cell lines from patients with primary immunodeficiencies represents a unique resource to investigate the pathophysiology of hematopoietic and extra-hematopoietic manifestations of these diseases, and may assist in the development of novel therapeutic approaches based on gene correction. PMID:21185069

Intra-discal injection of autologous, hypoxic cultured bone marrow-derived mesenchymal stem cells in five patients with chronic lower back pain: a long-term safety and feasibility study.

PubMed

Elabd, Christian; Centeno, Christopher J; Schultz, John R; Lutz, Gregory; Ichim, Thomas; Silva, Francisco J

2016-09-01

Chronic low back pain due to disc degeneration represents a major social and economic burden worldwide. The current standard of care is limited to symptomatic relief and no current approved therapy promotes disc regeneration. Bone marrow-derived mesenchymal stem cells (MSCs) are easily accessible and well characterized. These MSCs are multipotent and exhibit great tissue regenerative potential including bone, cartilage, and fibrous tissue regeneration. The use of this cell-based biologic for treating protruding disc herniation and/or intervertebral disc degeneration is a promising therapeutic strategy, due to their known regenerative, immuno-modulatory and anti-inflammatory properties. Five patients diagnosed with degenerative disc disease received an intra-discal injection of autologous, hypoxic cultured, bone marrow-derived mesenchymal stem cells (15.1-51.6 million cells) as part of a previous study. These patients were re-consented to participate in this study in order to assess long-term safety and feasibility of intra-discal injection of autologous, hypoxic cultured, bone marrow-derived mesenchymal stem cells 4-6 years post mesenchymal stem cell infusion. The follow-up study consisted of a physical examination, a low back MRI, and a quality of life questionnaire. Patients' lower back MRI showed absence of neoplasms or abnormalities surrounding the treated region. Based on the physical examination and the quality of life questionnaire, no adverse events were reported due to the procedure or to the stem cell treatment 4-6 years post autologous, hypoxic cultured mesenchymal stem cell infusion. All patients self-reported overall improvement, as well as improvement in strength, post stem cell treatment, and four out of five patients reported improvement in mobility. This early human clinical data suggests the safety and feasibility of the clinical use of hypoxic cultured bone marrow-derived mesenchymal stem cells for the treatment of lower back pain due to degenerative disc disorders and support further studies utilizing hypoxic cultured bone marrow-derived stem cells. The overall improvements reported are encouraging, but a larger double-blind, controlled, randomized clinical study with significant number of patients and implementation of validated endpoint measurements are next steps in order to demonstrate efficacy of this cell-based biologic.

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.

Disease and Stem Cell-Based Analysis of the 2014 ASNTR Meeting

PubMed Central

Eve, David J.

2015-01-01

A wide variety of subjects are presented at the annual American Society of Neural Therapy and Repair meeting every year, as typified by this summary of the 2014 meeting. Parkinson’s disease-related presentations were again the most popular topic, with traumatic brain injury, spinal cord injury, and stroke being close behind. Other disorders included Huntington’s disease, brain cancer, and bipolar disorders. Several studies were related to multiple diseases, and many studies attempted to reveal more about the disease process. The use of scaffolds, drugs, and gene therapy as disease models and/or potential therapies were also featured. An increasing proportion of presentations related to stem cells, with the study of multiple stem cell types being the most common. Induced pluripotent stem cells were increasingly popular, including two presentations each on a muscle-derived dedifferentiated cell type and cells derived from bipolar patients. Other stem cells, including neural stem cells, mesenchymal stem cells, umbilical cord blood cells, and embryonic stem cells, were featured. More than 55% of the stem cell studies involved transplantation, with human-derived cells being the most frequently transplanted, while rats were the most common recipient. Two human autologous studies for spinal cord injury and hypoxia-derived encephalopathy, while a further three allogenic studies for stroke and spinal cord injury, were also featured. This year’s meeting highlights the increasing promise of stem cells and other therapies for the treatment of neurodegenerative disorders. PMID:26858901

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

NASA Astrophysics Data System (ADS)

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

2017-07-01

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

Key Action Items for the Stem Cell Field: Looking Ahead to 2014

PubMed Central

Knoepfler, Paul S.

2013-01-01

Abstract The stem cell field is at a critical juncture in late 2013. We find ourselves buoyed by building momentum for both transformative basic science discoveries and clinical translation of stem cells. Cellular reprogramming has given the field exciting new avenues as well. The overall prospect of novel stem cell–based therapies becoming a reality for patients in the coming years has never seemed higher. At the same time, we face serious challenges. Some of these challenges, such as stem cell tourism, are familiar to us, although even those are evolving in ways that require adaptability and action by the stem cell field. Other new challenges are also emerging, including an urgent need for formal physician training in stem cells, regulatory compliance balanced with innovation and U.S. Food and Drug Administration reform, and savvy educational outreach. Looking ahead to 2014, both the challenges and opportunities for the stem cell field require a proactive, thoughtful approach to maximize the potential for a positive impact from stem cell advances. In this study, I discuss the key action items for the field as we look ahead to the coming year and beyond. PMID:24147571

Multiscale reconstruction of a synthetic biomimetic micro-niche for enhancing and monitoring the differentiation of stem cells.

PubMed

Li, Rui; Li, Jinming; Xu, Jianbin; Hong Wong, Dexter Siu; Chen, Xiaoyu; Yuan, Weihao; Bian, Liming

2018-05-04

Stem cells reside in a three-dimensional (3D) niche microenvironment, which provides specific cues, including cell-matrix interactions and soluble factors, that are essential to the differentiation of stem cells in vivo. Herein we demonstrate a general approach to the synthetic reconstruction of 3D biomimetic niche environment of stem cells by the multiscale combination of macroscopic porous hydrogels and a nanoscale upconversion nanoparticles (UCNP)-based nanocomplex. The porous biopolymeric hydrogels emulate the spongy bone microstructure and provide 3D environment conducive to the differentiation of seeded stem cells. The UCNP-based nanocomplex (Pur-UCNP-peptide-FITC), which is stably encapsulated in the porous hydrogels, emulates the repertoire of inductive factors in bone matrix by maintaining localized long-term delivery of inductive small molecules. The nanocomplex also generates biomarker-specific reporting emissions that correlate with the extent and stage of differentiation of the stem cells in synthetic niche, thereby allowing long-term tracking of stem cell fate in a non-contact, non-destructive, and potentially high-throughput manner in living cultures. To the best of our knowledge, this is first demonstration of synthetic niche reconstruction. The modular nature of this synthetic niche platform allows various parameters to be easily tuned to accommodate a variety of fundamental studies of dynamic cellular events under controlled settings. Copyright © 2018 Elsevier Ltd. All rights reserved.

Differential Gene Expression Profiling of Dystrophic Dog Muscle after MuStem Cell Transplantation

PubMed Central

Babarit, Candice; Larcher, Thibaut; Dubreil, Laurence; Leroux, Isabelle; Zuber, Céline; Ledevin, Mireille; Deschamps, Jack-Yves; Fromes, Yves; Cherel, Yan; Guevel, Laetitia; Rouger, Karl

2015-01-01

Background Several adult stem cell populations exhibit myogenic regenerative potential, thus representing attractive candidates for therapeutic approaches of neuromuscular diseases such as Duchenne Muscular Dystrophy (DMD). We have recently shown that systemic delivery of MuStem cells, skeletal muscle-resident stem cells isolated in healthy dog, generates the remodelling of muscle tissue and gives rise to striking clinical benefits in Golden Retriever Muscular Dystrophy (GRMD) dog. This global effect, which is observed in the clinically relevant DMD animal model, leads us to question here the molecular pathways that are impacted by MuStem cell transplantation. To address this issue, we compare the global gene expression profile between healthy, GRMD and MuStem cell treated GRMD dog muscle, four months after allogenic MuStem cell transplantation. Results In the dystrophic context of the GRMD dog, disease-related deregulation is observed in the case of 282 genes related to various processes such as inflammatory response, regeneration, calcium ion binding, extracellular matrix organization, metabolism and apoptosis regulation. Importantly, we reveal the impact of MuStem cell transplantation on several molecular and cellular pathways based on a selection of 31 genes displaying signals specifically modulated by the treatment. Concomitant with a diffuse dystrophin expression, a histological remodelling and a stabilization of GRMD dog clinical status, we show that cell delivery is associated with an up-regulation of genes reflecting a sustained enhancement of muscle regeneration. We also identify a decreased mRNA expression of a set of genes having metabolic functions associated with lipid homeostasis and energy. Interestingly, ubiquitin-mediated protein degradation is highly enhanced in GRMD dog muscle after systemic delivery of MuStem cells. Conclusions Overall, our results provide the first high-throughput characterization of GRMD dog muscle and throw new light on the complex molecular/cellular effects associated with muscle repair and the clinical efficacy of MuStem cell-based therapy. PMID:25955839

Stem cell-biomaterial interactions for regenerative medicine.

PubMed

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

2012-01-01

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

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.

The New Federalism: State Policies Regarding Embryonic Stem Cell Research.

PubMed

Acosta, Nefi D; Golub, Sidney H

2016-09-01

Stem cell policy in the United States is an amalgam of federal and state policies. The scientific development of human pluripotent embryonic stem cells (ESCs) triggered a contentious national stem cell policy debate during the administration of President George W. Bush. The Bush "compromise" that allowed federal funding to study only a very limited number of ESC derived cell lines did not satisfy either the researchers or the patient advocates who saw great medical potential being stifled. Neither more restrictive legislation nor expansion of federal funding proved politically possible and the federal impasse opened the door for a variety of state-based experiments. In 2004, California became the largest and most influential state venture into stem cell research by passing "Prop 71," a voter initiative that created a new stem cell agency and funded it with $3 billion. Several states followed suit with similar programs to protect the right of investigators to do stem cell research and in some cases to invest state funding in such projects. Other states devised legislation to restrict stem cell research and in five states, criminal penalties were included. Thus, the US stem cell policy is a patchwork of multiple, often conflicting, state and federal policies. © 2016 American Society of Law, Medicine & Ethics.

Stem cells in drug discovery, tissue engineering, and regenerative medicine: emerging opportunities and challenges.

PubMed

Nirmalanandhan, Victor Sanjit; Sittampalam, G Sitta

2009-08-01

Stem cells, irrespective of their origin, have emerged as valuable reagents or tools in human health in the past 2 decades. Initially, a research tool to study fundamental aspects of developmental biology is now the central focus of generating transgenic animals, drug discovery, and regenerative medicine to address degenerative diseases of multiple organ systems. This is because stem cells are pluripotent or multipotent cells that can recapitulate developmental paths to repair damaged tissues. However, it is becoming clear that stem cell therapy alone may not be adequate to reverse tissue and organ damage in degenerative diseases. Existing small-molecule drugs and biologicals may be needed as "molecular adjuvants" or enhancers of stem cells administered in therapy or adult stem cells in the diseased tissues. Hence, a combination of stem cell-based, high-throughput screening and 3D tissue engineering approaches is necessary to advance the next wave of tools in preclinical drug discovery. In this review, the authors have attempted to provide a basic account of various stem cells types, as well as their biology and signaling, in the context of research in regenerative medicine. An attempt is made to link stem cells as reagents, pharmacology, and tissue engineering as converging fields of research for the next decade.

Exploring pericyte and cardiac stem cell secretome unveils new tactics for drug discovery.

PubMed

Ellison-Hughes, Georgina M; Madeddu, Paolo

2017-03-01

Ischaemic diseases remain a major cause of morbidity and mortality despite continuous advancements in medical and interventional treatments. Moreover, available drugs reduce symptoms associated with tissue ischaemia, without providing a definitive repair. Cardiovascular regenerative medicine is an expanding field of research that aims to improve the treatment of ischaemic disorders through restorative methods, such as gene therapy, stem cell therapy, and tissue engineering. Stem cell transplantation has salutary effects through direct and indirect actions, the latter being attributable to growth factors and cytokines released by stem cells and influencing the endogenous mechanisms of repair. Autologous stem cell therapies offer less scope for intellectual property coverage and have limited scalability. On the other hand, off-the-shelf cell products and derivatives from the stem cell secretome have a greater potential for large-scale distribution, thus enticing commercial investors and reciprocally producing more significant medical and social benefits. This review focuses on the paracrine properties of cardiac stem cells and pericytes, two stem cell populations that are increasingly attracting the attention of regenerative medicine operators. It is likely that new cardiovascular drugs are introduced in the next future by applying different approaches based on the refinement of the stem cell secretome. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Paracrine effects and heterogeneity of marrow-derived stem/progenitor cells: relevance for the treatment of respiratory diseases.

PubMed

Conese, Massimo; Carbone, Annalucia; Castellani, Stefano; Di Gioia, Sante

2013-01-01

Stem cell-based treatment may represent a hope for the treatment of acute lung injury and pulmonary fibrosis, and other chronic lung diseases, such as cystic fibrosis, asthma and chronic obstructive pulmonary disease (COPD). It is well established in preclinical models that bone marrow-derived stem and progenitor cells exert beneficial effects on inflammation, immune responses and repairing of damage in virtually all lung-borne diseases. While it was initially thought that the positive outcome was due to a direct engraftment of these cells into the lung as endothelial and epithelial cells, paracrine factors are now considered the main mechanism through which stem and progenitor cells exert their therapeutic effect. This knowledge has led to the clinical use of marrow cells in pulmonary hypertension with endothelial progenitor cells (EPCs) and in COPD with mesenchymal stromal (stem) cells (MSCs). Bone marrow-derived stem cells, including hematopoietic stem/progenitor cells, MSCs, EPCs and fibrocytes, encompass a wide array of cell subsets with different capacities of engraftment and injured tissue-regenerating potential. The characterization/isolation of the stem cell subpopulations represents a major challenge to improve the efficacy of transplantation protocols used in regenerative medicine and applied to lung disorders. Copyright © 2013 S. Karger AG, Basel.

Limbal Stem Cell Deficiency and Treatment with Stem Cell Transplantation.

PubMed

Barut Selver, Özlem; Yağcı, Ayşe; Eğrilmez, Sait; Gürdal, Mehmet; Palamar, Melis; Çavuşoğlu, Türker; Ateş, Utku; Veral, Ali; Güven, Çağrı; Wolosin, Jose Mario

2017-10-01

The cornea is the outermost tissue of the eye and it must be transparent for the maintenance of good visual function. The superficial epithelium of the cornea, which is renewed continuously by corneal stem cells, plays a critical role in the permanence of this transparency. These stem cells are localized at the cornea-conjunctival transition zone, referred to as the limbus. When this zone is affected/destroyed, limbal stem cell deficiency ensues. Loss of limbal stem cell function allows colonization of the corneal surface by conjunctival epithelium. Over 6 million people worldwide are affected by corneal blindness, and limbal stem cell deficiency is one of the main causes. Fortunately, it is becoming possible to recover vision by autologous transplantation of limbal cells obtained from the contralateral eye in unilateral cases. Due to the potential risks to the donor eye, only a small amount of tissue can be obtained, in which only 1-2% of the limbal epithelial cells are actually limbal stem cells. Vigorous attempts are being made to expand limbal stem cells in culture to preserve or even enrich the stem cell population. Ex vivo expanded limbal stem cell treatment in limbal stem cell deficiency was first reported in 1997. In the 20 years since, various protocols have been developed for the cultivation of limbal epithelial cells. It is still not clear which method promotes effective stem cell viability and this remains a subject of ongoing research. The most preferred technique for limbal cell culture is the explant culture model. In this approach, a small donor eye limbal biopsy is placed as an explant onto a biocompatible substrate (preferably human amniotic membrane) for expansion. The outgrowth (cultivated limbal epithelial cells) is then surgically transferred to the recipient eye. Due to changing regulations concerning cell-based therapy, the implementation of cultivated limbal epithelial transplantation in accordance with Good Laboratory Practice using xenobiotic-free systems is becoming widely accepted both in Turkey and worldwide.

Stem cell treatment of degenerative eye disease.

PubMed

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

2015-05-01

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

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.

Nanotubes mediate niche-stem cell signaling in the Drosophila testis

PubMed Central

Inaba, Mayu; Buszczak, Michael; Yamashita, Yukiko M.

2015-01-01

Stem cell niches provide resident stem cells with signals that specify their identity. Niche signals act over a short-range such that only stem cells but not their differentiating progeny receive the self-renewing signals1. However, the cellular mechanisms that limit niche signaling to stem cells remain poorly understood. Here we show that the Drosophila male germline stem cells (GSCs) form previously unrecognized structures, microtubule-based (MT)-nanotubes, which extend into the hub, a major niche component. MT-nanotubes are observed specifically within GSC populations, and require IFT (intraflagellar transport) proteins for their formation. The BMP receptor Tkv localizes to MT-nanotubes. Perturbation of MT-nanotubes compromises activation of Dpp signaling within GSCs, leading to GSC loss. Moreover, Dpp ligand and Tkv receptor interaction is necessary and sufficient for MT-nanotube formation. We propose that MT-nanotubes provide a novel mechanism for selective receptor-ligand interaction, contributing to the short-range nature of niche-stem cell signaling. PMID:26131929

Therapeutic targeting of the p53 pathway in cancer stem cells

PubMed Central

Prabhu, Varun V.; Allen, Joshua E.; Hong, Bo; Zhang, Shengliang; Cheng, Hairong; El-Deiry, Wafik S.

2013-01-01

Introduction Cancer stem cells are a high profile drug target for cancer therapeutics due to their indispensable role in cancer progression, maintenance, and therapeutic resistance. Restoring wild-type p53 function is an attractive new therapeutic approach for the treatment of cancer due to the well-described powerful tumor suppressor function of p53. As emerging evidence intimately links p53 and stem cell biology, this approach also provides an opportunity to target cancer stem cells. Areas covered Therapeutic approaches to restore the function of wild-type p53, cancer and normal stem cell biology in relation to p53, and the downstream effects of p53 on cancer stem cells. Expert opinion The restoration of wild-type p53 function by targeting p53 directly, its interacting proteins, or its family members holds promise as a new class of cancer therapies. This review examines the impact that such therapies may have on normal and cancer stem cells based on the current evidence linking p53 signaling with these populations. PMID:22998602

Conserved functional antagonism of CELF and MBNL proteins controls stem cell-specific alternative splicing in planarians

PubMed Central

Solana, Jordi; Irimia, Manuel; Ayoub, Salah; Orejuela, Marta Rodriguez; Zywitza, Vera; Jens, Marvin; Tapial, Javier; Ray, Debashish; Morris, Quaid; Hughes, Timothy R; Blencowe, Benjamin J; Rajewsky, Nikolaus

2016-01-01

In contrast to transcriptional regulation, the function of alternative splicing (AS) in stem cells is poorly understood. In mammals, MBNL proteins negatively regulate an exon program specific of embryonic stem cells; however, little is known about the in vivo significance of this regulation. We studied AS in a powerful in vivo model for stem cell biology, the planarian Schmidtea mediterranea. We discover a conserved AS program comprising hundreds of alternative exons, microexons and introns that is differentially regulated in planarian stem cells, and comprehensively identify its regulators. We show that functional antagonism between CELF and MBNL factors directly controls stem cell-specific AS in planarians, placing the origin of this regulatory mechanism at the base of Bilaterians. Knockdown of CELF or MBNL factors lead to abnormal regenerative capacities by affecting self-renewal and differentiation sets of genes, respectively. These results highlight the importance of AS interactions in stem cell regulation across metazoans. DOI: http://dx.doi.org/10.7554/eLife.16797.001 PMID:27502555

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.

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

Induced Pluripotent Stem Cells and Periodontal Regeneration.

PubMed

Du, Mi; Duan, Xuejing; Yang, Pishan

Periodontitis is a chronic inflammatory disease which leads to destruction of both the soft and hard tissues of the periodontium. Tissue engineering is a therapeutic approach in regenerative medicine that aims to induce new functional tissue regeneration via the synergistic combination of cells, biomaterials, and/or growth factors. Advances in our understanding of the biology of stem cells, including embryonic stem cells and mesenchymal stem cells, have provided opportunities for periodontal tissue engineering. However, there remain a number of limitations affecting their therapeutic efficiency. Due to the considerable proliferation and differentiation capacities, recently described induced pluripotent stem cells (iPSCs) provide a new way for cell-based therapies for periodontal regeneration. This review outlines the latest status of periodontal tissue engineering and highlights the potential use of iPSCs in periodontal tissue regeneration.

Reverse engineering life: physical and chemical mimetics for controlled stem cell differentiation into cardiomyocytes.

PubMed

Skuse, Gary R; Lamkin-Kennard, Kathleen A

2013-01-01

Our ability to manipulate stem cells in order to induce differentiation along a desired developmental pathway has improved immeasurably in recent years. That is in part because we have a better understanding of the intracellular and extracellular signals that regulate differentiation. However, there has also been a realization that stem cell differentiation is not regulated only by chemical signals but also by the physical milieu in which a particular stem cell exists. In this regard we are challenged to mimic both chemical and physical environments. Herein we describe a method to induce stem cell differentiation into cardiomyocytes using a combination of chemical and physical cues. This method can be applied to produce differentiated cells for research and potentially for cell-based therapy of cardiomyopathies.

Purpose and regulation of stem cells: a systems-biology view from the Caenorhabditis elegans germ line.

PubMed

Cinquin, Olivier

2009-01-01

Stem cells are expected to play a key role in the development and maintenance of organisms, and hold great therapeutic promises. However, a number of questions must be answered to achieve an understanding of stem cells and put them to use. Here I review some of these questions, and how they relate to the model system provided by the Caenorhabditis elegans germ line, which is exceptional in its thorough genetic characterization and experimental accessibility under in vivo conditions. A fundamental question is how to define a stem cell; different definitions can be adopted that capture different features of interest. In the C. elegans germ line, stem cells can be defined by cell lineage or by cell commitment ('commitment' must itself be carefully defined). These definitions are associated with two other important questions about stem cells: their functions (which must be addressed following a systems approach, based on an evolutionary perspective) and their regulation. I review possible functions and their evolutionary groundings, including genome maintenance and powerful regulation of cell proliferation and differentiation, and possible regulatory mechanisms, including asymmetrical division and control of transit amplification by a developmental timer. I draw parallels between Drosophila and C. elegans germline stem cells; such parallels raise intriguing questions about Drosophila stem cells. I conclude by showing that the C. elegans germ line bears similarities with a number of other stem cell systems, which underscores its relevance to the understanding of stem cells.

The Emerging Cell Biology of Thyroid Stem Cells

PubMed Central

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

2011-01-01

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

Imaging transplanted stem cells in real time using an MRI dual-contrast method

PubMed Central

Ngen, Ethel J.; Wang, Lee; Kato, Yoshinori; Krishnamachary, Balaji; Zhu, Wenlian; Gandhi, Nishant; Smith, Barbara; Armour, Michael; Wong, John; Gabrielson, Kathleen; Artemov, Dmitri

2015-01-01

Stem cell therapies are currently being investigated for the repair of brain injuries. Although exogenous stem cell labelling with superparamagnetic iron oxide nanoparticles (SPIONs) prior to transplantation provides a means to noninvasively monitor stem cell transplantation by magnetic resonance imaging (MRI), monitoring cell death is still a challenge. Here, we investigate the feasibility of using an MRI dual-contrast technique to detect cell delivery, cell migration and cell death after stem cell transplantation. Human mesenchymal stem cells were dual labelled with SPIONs and gadolinium-based chelates (GdDTPA). The viability, proliferation rate, and differentiation potential of the labelled cells were then evaluated. The feasibility of this MRI technique to distinguish between live and dead cells was next evaluated using MRI phantoms, and in vivo using both immune-competent and immune-deficient mice, following the induction of brain injury in the mice. All results were validated with bioluminescence imaging. In live cells, a negative (T2/T2*) MRI contrast predominates, and is used to track cell delivery and cell migration. Upon cell death, a diffused positive (T1) MRI contrast is generated in the vicinity of the dead cells, and serves as an imaging marker for cell death. Ultimately, this technique could be used to manage stem cell therapies. PMID:26330231

Imaging transplanted stem cells in real time using an MRI dual-contrast method.

PubMed

Ngen, Ethel J; Wang, Lee; Kato, Yoshinori; Krishnamachary, Balaji; Zhu, Wenlian; Gandhi, Nishant; Smith, Barbara; Armour, Michael; Wong, John; Gabrielson, Kathleen; Artemov, Dmitri

2015-09-02

Stem cell therapies are currently being investigated for the repair of brain injuries. Although exogenous stem cell labelling with superparamagnetic iron oxide nanoparticles (SPIONs) prior to transplantation provides a means to noninvasively monitor stem cell transplantation by magnetic resonance imaging (MRI), monitoring cell death is still a challenge. Here, we investigate the feasibility of using an MRI dual-contrast technique to detect cell delivery, cell migration and cell death after stem cell transplantation. Human mesenchymal stem cells were dual labelled with SPIONs and gadolinium-based chelates (GdDTPA). The viability, proliferation rate, and differentiation potential of the labelled cells were then evaluated. The feasibility of this MRI technique to distinguish between live and dead cells was next evaluated using MRI phantoms, and in vivo using both immune-competent and immune-deficient mice, following the induction of brain injury in the mice. All results were validated with bioluminescence imaging. In live cells, a negative (T2/T2*) MRI contrast predominates, and is used to track cell delivery and cell migration. Upon cell death, a diffused positive (T1) MRI contrast is generated in the vicinity of the dead cells, and serves as an imaging marker for cell death. Ultimately, this technique could be used to manage stem cell therapies.

Human neural progenitor cells retain viability, phenotype, proliferation, and lineage differentiation when labeled with a novel iron oxide nanoparticle, Molday ION Rhodamine B

PubMed Central

Shen, Wei-Bin; Plachez, Celine; Chan, Amanda; Yarnell, Deborah; Puche, Adam C; Fishman, Paul S; Yarowsky, Paul

2013-01-01

Ultrasmall superparamagnetic iron-oxide particles (USPIOs) loaded into stem cells have been suggested as a way to track stem cell transplantation with magnetic resonance imaging, but the labeling, and post-labeling proliferation, viability, differentiation, and retention of USPIOs within the stem cells have yet to be determined for each type of stem cell and for each type of USPIO. Molday ION Rhodamine B™ (BioPAL, Worcester, MA, USA) (MIRB) has been shown to be a USPIO labeling agent for mesenchymal stem cells, glial progenitor cells, and stem cell lines. In this study, we have evaluated MIRB labeling in human neuroprogenitor cells and found that human neuroprogenitor cells are effectively labeled with MIRB without use of transfection reagents. Viability, proliferation, and differentiation properties are unchanged between MIRB-labeled neuroprogenitors cells and unlabeled cells. Moreover, MIRB-labeled human neuroprogenitor cells can be frozen, thawed, and replated without loss of MIRB or even without loss of their intrinsic biology. Overall, those results show that MIRB has advantageous properties that can be used for cell-based therapy. PMID:24348036

Bioreactor engineering of stem cell environments.

PubMed

Tandon, Nina; Marolt, Darja; Cimetta, Elisa; Vunjak-Novakovic, Gordana

2013-11-15

Stem cells hold promise to revolutionize modern medicine by the development of new therapies, disease models and drug screening systems. Standard cell culture systems have limited biological relevance because they do not recapitulate the complex 3-dimensional interactions and biophysical cues that characterize the in vivo environment. In this review, we discuss the current advances in engineering stem cell environments using novel biomaterials and bioreactor technologies. We also reflect on the challenges the field is currently facing with regard to the translation of stem cell based therapies into the clinic. Copyright © 2013 Elsevier Inc. All rights reserved.

Method for evaluation of human induced pluripotent stem cell quality using image analysis based on the biological morphology of cells.

PubMed

Wakui, Takashi; Matsumoto, Tsuyoshi; Matsubara, Kenta; Kawasaki, Tomoyuki; Yamaguchi, Hiroshi; Akutsu, Hidenori

2017-10-01

We propose an image analysis method for quality evaluation of human pluripotent stem cells based on biologically interpretable features. It is important to maintain the undifferentiated state of induced pluripotent stem cells (iPSCs) while culturing the cells during propagation. Cell culture experts visually select good quality cells exhibiting the morphological features characteristic of undifferentiated cells. Experts have empirically determined that these features comprise prominent and abundant nucleoli, less intercellular spacing, and fewer differentiating cellular nuclei. We quantified these features based on experts' visual inspection of phase contrast images of iPSCs and found that these features are effective for evaluating iPSC quality. We then developed an iPSC quality evaluation method using an image analysis technique. The method allowed accurate classification, equivalent to visual inspection by experts, of three iPSC cell lines.

Skeletal tissue engineering using mesenchymal or embryonic stem cells: clinical and experimental data.

PubMed

Gamie, Zakareya; MacFarlane, Robert J; Tomkinson, Alicia; Moniakis, Alexandros; Tran, Gui Tong; Gamie, Yehya; Mantalaris, Athanasios; Tsiridis, Eleftherios

2014-11-01

Mesenchymal stem cells (MSCs) can be obtained from a wide variety of tissues for bone tissue engineering such as bone marrow, adipose, birth-associated, peripheral blood, periosteum, dental and muscle. MSCs from human fetal bone marrow and embryonic stem cells (ESCs) are also promising cell sources. In vitro, in vivo and clinical evidence was collected using MEDLINE® (1950 to January 2014), EMBASE (1980 to January 2014) and Google Scholar (1980 to January 2014) databases. Enhanced results have been found when combining bone marrow-derived mesenchymal stem cells (BMMSCs) with recently developed scaffolds such as glass ceramics and starch-based polymeric scaffolds. Preclinical studies investigating adipose tissue-derived stem cells and umbilical cord tissue-derived stem cells suggest that they are likely to become promising alternatives. Stem cells derived from periosteum and dental tissues such as the periodontal ligament have an osteogenic potential similar to BMMSCs. Stem cells from human fetal bone marrow have demonstrated superior proliferation and osteogenic differentiation than perinatal and postnatal tissues. Despite ethical concerns and potential for teratoma formation, developments have also been made for the use of ESCs in terms of culture and ideal scaffold.

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

Commentary: "re-programming or selecting adult stem cells?".

PubMed

Trosko, James E

2008-01-01

The recent observations that embryonic stemness-associated genes could assist in the "de-differentiation" of adult skin fibroblast cells to "embryonic-like stem cells", using the "somatic cell nuclear transfer" techniques, have been interpreted as indicating a "re-programming" of genes. These reports have demonstrated a "proof of principle" approach to by-pass many, but not all, of the ethical, scientific and medical limitations of the "therapeutic cloning" of embryonic stem cells from embryos. However, while the interpretation that real "re-programming" of all those somatic fibroblastic differentiation genes might be correct, there does exists an alternative hypothesis of these exciting results. Based on the fact that multipotent adult stem cells exist in most, if not all, adult organs, the possibility exists that all these recent "re-programming" results, using the somatic nuclear transfer techniques, actually were the results of transferred rare nuclear material from the adult stem cells residing in the skin of the mouse, monkey and human samples. An examination of the rationale for this challenging hypothesis has been drawn from the hypothesis of the "stem cell theory of cancer", as well as from the field of human adult stem cells research.

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

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.

Practical Modeling Concepts for Connective Tissue Stem Cell and Progenitor Compartment Kinetics

PubMed Central

2003-01-01

Stem cell activation and development is central to skeletal development, maintenance, and repair, as it is for all tissues. However, an integrated model of stem cell proliferation, differentiation, and transit between functional compartments has yet to evolve. In this paper, the authors review current concepts in stem cell biology and progenitor cell growth and differentiation kinetics in the context of bone formation. A cell-based modeling strategy is developed and offered as a tool for conceptual and quantitative exploration of the key kinetic variables and possible organizational hierarchies in bone tissue development and remodeling, as well as in tissue engineering strategies for bone repair. PMID:12975533

Rejuvenating Strategies for Stem Cell-based Therapies in Aging

PubMed Central

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

2017-01-01

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

Establishment and Characterization of Immortalized Minipig Neural Stem Cell Line

PubMed Central

Choi, Sung S.; Yoon, Seung-Bin; Lee, Sang-Rae; Kim, Sun-Uk; Cha, Young Joo; Lee, Daniel; Kim, Seung U.; Chang, Kyu-Tae; Lee, Hong J.

2017-01-01

Despite the increasing importance of minipigs in biomedical research, there has been relatively little research concerning minipig-derived adult stem cells as a promising research tool that could be used to develop stem cell-based therapies. We first generated immortalized neural stem cells (iNSCs) from primary minipig olfactory bulb cells (pmpOBCs) and defined the characteristics of the cell line. Primary neural cells were prepared from minipig neonate olfactory bulbs and immortalized by infection with retrovirus carrying the v-myc gene. The minipig iNSCs (mpiNSCs) had normal karyotypes and expressed NSC-specific markers, including nestin, vimentin, Musashi1, and SOX2, suggesting a similarity to human NSCs. On the basis of the global gene expression profiles from the microarray analysis, neurogenesis-associated transcript levels were predominantly altered in mpiNSCs compared with pmpOBCs. These findings increase our understanding of minipig stem cells and contribute to the utility of mpiNSCs as resources for immortalized stem cell experiments. PMID:27524466

Müller stem cell dependent retinal regeneration.

PubMed

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

2017-01-01

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

Establishment and Characterization of Immortalized Minipig Neural Stem Cell Line.

PubMed

Choi, Sung S; Yoon, Seung-Bin; Lee, Sang-Rae; Kim, Sun-Uk; Cha, Young Joo; Lee, Daniel; Kim, Seung U; Chang, Kyu-Tae; Lee, Hong J

2017-02-16

Despite the increasing importance of minipigs in biomedical research, there has been relatively little research concerning minipig-derived adult stem cells as a promising research tool that could be used to develop stem cell-based therapies. We first generated immortalized neural stem cells (iNSCs) from primary minipig olfactory bulb cells (pmpOBCs) and defined the characteristics of the cell line. Primary neural cells were prepared from minipig neonate olfactory bulbs and immortalized by infection with retrovirus carrying the v-myc gene. The minipig iNSCs (mpiNSCs) had normal karyotypes and expressed NSC-specific markers, including nestin, vimentin, Musashi1, and SOX2, suggesting a similarity to human NSCs. On the basis of the global gene expression profiles from the microarray analysis, neurogenesis-associated transcript levels were predominantly altered in mpiNSCs compared with pmpOBCs. These findings increase our understanding of minipig stem cells and contribute to the utility of mpiNSCs as resources for immortalized stem cell experiments.

Mesenchymal Stem Cells From Bone Marrow, Adipose Tissue, and Lung Tissue Differentially Mitigate Lung and Distal Organ Damage in Experimental Acute Respiratory Distress Syndrome.

PubMed

Silva, Johnatas D; Lopes-Pacheco, Miquéias; Paz, Ana H R; Cruz, Fernanda F; Melo, Elga B; de Oliveira, Milena V; Xisto, Débora G; Capelozzi, Vera L; Morales, Marcelo M; Pelosi, Paolo; Cirne-Lima, Elizabeth; Rocco, Patricia R M

2018-02-01

Mesenchymal stem cells-based therapies have shown promising effects in experimental acute respiratory distress syndrome. Different mesenchymal stem cells sources may result in diverse effects in respiratory diseases; however, there is no information regarding the best source of mesenchymal stem cells to treat pulmonary acute respiratory distress syndrome. We tested the hypothesis that mesenchymal stem cells derived from bone marrow, adipose tissue, and lung tissue would lead to different beneficial effects on lung and distal organ damage in experimental pulmonary acute respiratory distress syndrome. Animal study and primary cell culture. Laboratory investigation. Seventy-five Wistar rats. Wistar rats received saline (control) or Escherichia coli lipopolysaccharide (acute respiratory distress syndrome) intratracheally. On day 2, acute respiratory distress syndrome animals were further randomized to receive saline or bone marrow, adipose tissue, or lung tissue mesenchymal stem cells (1 × 10 cells) IV. Lung mechanics, histology, and protein levels of inflammatory mediators and growth factors were analyzed 5 days after mesenchymal stem cells administration. RAW 264.7 cells (a macrophage cell line) were incubated with lipopolysaccharide followed by coculture or not with bone marrow, adipose tissue, and lung tissue mesenchymal stem cells (10 cells/mL medium). Regardless of mesenchymal stem cells source, cells administration improved lung function and reduced alveolar collapse, tissue cellularity, collagen, and elastic fiber content in lung tissue, as well as decreased apoptotic cell counts in liver. Bone marrow and adipose tissue mesenchymal stem cells administration also reduced levels of tumor necrosis factor-α, interleukin-1β, keratinocyte-derived chemokine, transforming growth factor-β, and vascular endothelial growth factor, as well as apoptotic cell counts in lung and kidney, while increasing expression of keratinocyte growth factor in lung tissue. Additionally, mesenchymal stem cells differently modulated the secretion of biomarkers by macrophages depending on their source. Mesenchymal stem cells from different sources led to variable responses in lungs and distal organs. Bone marrow and adipose tissue mesenchymal stem cells yielded greater beneficial effects than lung tissue mesenchymal stem cells. These findings may be regarded as promising in clinical trials.

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.

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.

Stem cells for cardiac repair: an introduction

PubMed Central

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

2013-01-01

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

Isolation of skeletal muscle stem cells by fluorescence-activated cell sorting.

PubMed

Liu, Ling; Cheung, Tom H; Charville, Gregory W; Rando, Thomas A

2015-10-01

The prospective isolation of purified stem cell populations has dramatically altered the field of stem cell biology, and it has been a major focus of research across tissues in different organisms. Muscle stem cells (MuSCs) are now among the most intensely studied stem cell populations in mammalian systems, and the prospective isolation of these cells has allowed cellular and molecular characterizations that were not dreamed of a decade ago. In this protocol, we describe how to isolate MuSCs from limb muscles of adult mice by fluorescence-activated cell sorting (FACS). We provide a detailed description of the physical and enzymatic dissociation of mononucleated cells from limb muscles, a procedure that is essential in order to maximize cell yield. We also describe a FACS-based method that is used subsequently to obtain highly pure populations of either quiescent or activated MuSCs (VCAM(+)CD31(-)CD45(-)Sca1(-)). The isolation process takes ∼5-6 h to complete. The protocol also allows for the isolation of endothelial cells, hematopoietic cells and mesenchymal stem cells from muscle tissue.

Agent-Based Modeling of Cancer Stem Cell Driven Solid Tumor Growth.

PubMed

Poleszczuk, Jan; Macklin, Paul; Enderling, Heiko

2016-01-01

Computational modeling of tumor growth has become an invaluable tool to simulate complex cell-cell interactions and emerging population-level dynamics. Agent-based models are commonly used to describe the behavior and interaction of individual cells in different environments. Behavioral rules can be informed and calibrated by in vitro assays, and emerging population-level dynamics may be validated with both in vitro and in vivo experiments. Here, we describe the design and implementation of a lattice-based agent-based model of cancer stem cell driven tumor growth.

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).

Scalable 96-well Plate Based iPSC Culture and Production Using a Robotic Liquid Handling System.

PubMed

Conway, Michael K; Gerger, Michael J; Balay, Erin E; O'Connell, Rachel; Hanson, Seth; Daily, Neil J; Wakatsuki, Tetsuro

2015-05-14

Continued advancement in pluripotent stem cell culture is closing the gap between bench and bedside for using these cells in regenerative medicine, drug discovery and safety testing. In order to produce stem cell derived biopharmaceutics and cells for tissue engineering and transplantation, a cost-effective cell-manufacturing technology is essential. Maintenance of pluripotency and stable performance of cells in downstream applications (e.g., cell differentiation) over time is paramount to large scale cell production. Yet that can be difficult to achieve especially if cells are cultured manually where the operator can introduce significant variability as well as be prohibitively expensive to scale-up. To enable high-throughput, large-scale stem cell production and remove operator influence novel stem cell culture protocols using a bench-top multi-channel liquid handling robot were developed that require minimal technician involvement or experience. With these protocols human induced pluripotent stem cells (iPSCs) were cultured in feeder-free conditions directly from a frozen stock and maintained in 96-well plates. Depending on cell line and desired scale-up rate, the operator can easily determine when to passage based on a series of images showing the optimal colony densities for splitting. Then the necessary reagents are prepared to perform a colony split to new plates without a centrifugation step. After 20 passages (~3 months), two iPSC lines maintained stable karyotypes, expressed stem cell markers, and differentiated into cardiomyocytes with high efficiency. The system can perform subsequent high-throughput screening of new differentiation protocols or genetic manipulation designed for 96-well plates. This technology will reduce the labor and technical burden to produce large numbers of identical stem cells for a myriad of applications.

Potential for Stem Cell-Based Periodontal Therapy

PubMed Central

Bassir, Seyed Hossein; Wisitrasameewong, Wichaya; Raanan, Justin; Ghaffarigarakani, Sasan; Chung, Jamie; Freire, Marcelo; Andrada, Luciano C.; Intini, Giuseppe

2015-01-01

Periodontal diseases are highly prevalent and are linked to several systemic diseases. The goal of periodontal treatment is to halt the progression of the disease and regenerate the damaged tissue. However, achieving complete and functional periodontal regeneration is challenging because the periodontium is a complex apparatus composed of different tissues, including bone, cementum, and periodontal ligament. Stem cell-based regenerative therapy may represent an effective therapeutic tool for periodontal regeneration due to their plasticity and ability to differentiate into different cell lineages. This review presents and critically analyzes the available information on stem cell-based therapy for the regeneration of periodontal tissues and suggests new avenues for the development of more effective therapeutic protocols. PMID:26058394

In vivo stem cell tracking with imageable nanoparticles that bind bioorthogonal chemical receptors on the stem cell surface.

PubMed

Lee, Sangmin; Yoon, Hwa In; Na, Jin Hee; Jeon, Sangmin; Lim, Seungho; Koo, Heebeom; Han, Sang-Soo; Kang, Sun-Woong; Park, Soon-Jung; Moon, Sung-Hwan; Park, Jae Hyung; Cho, Yong Woo; Kim, Byung-Soo; Kim, Sang Kyoon; Lee, Taekwan; Kim, Dongkyu; Lee, Seulki; Pomper, Martin G; Kwon, Ick Chan; Kim, Kwangmeyung

2017-09-01

It is urgently necessary to develop reliable non-invasive stem cell imaging technology for tracking the in vivo fate of transplanted stem cells in living subjects. Herein, we developed a simple and well controlled stem cell imaging method through a combination of metabolic glycoengineering and bioorthogonal copper-free click chemistry. Firstly, the exogenous chemical receptors containing azide (-N 3 ) groups were generated on the surfaces of stem cells through metabolic glycoengineering using metabolic precursor, tetra-acetylated N-azidoacetyl-d-mannosamine(Ac 4 ManNAz). Next, bicyclo[6.1.0]nonyne-modified glycol chitosan nanoparticles (BCN-CNPs) were prepared as imageable nanoparticles to deliver different imaging agents. Cy5.5, iron oxide nanoparticles and gold nanoparticles were conjugated or encapsulated to BCN-CNPs for optical, MR and CT imaging, respectively. These imageable nanoparticles bound chemical receptors on the Ac 4 ManNAz-treated stem cell surface specifically via bioorthogonal copper-free click chemistry. Then they were rapidly taken up by the cell membrane turn-over mechanism resulting in higher endocytic capacity compared non-specific uptake of nanoparticles. During in vivo animal test, BCN-CNP-Cy5.5-labeled stem cells could be continuously tracked by non-invasive optical imaging over 15 days. Furthermore, BCN-CNP-IRON- and BCN-CNP-GOLD-labeled stem cells could be efficiently visualized using in vivo MR and CT imaging demonstrating utility of our stem cell labeling method using chemical receptors. These results conclude that our method based on metabolic glycoengineering and bioorthogonal copper-free click chemistry can stably label stem cells with diverse imageable nanoparticles representing great potential as new stem cell imaging technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

α6-Integrin alternative splicing: distinct cytoplasmic variants in stem cell fate specification and niche interaction.

PubMed

Zhou, Zijing; Qu, Jing; He, Li; Peng, Hong; Chen, Ping; Zhou, Yong

2018-05-02

α6-Integrin subunit (also known as CD49f) is a stemness signature that has been found on the plasma membrane of more than 30 stem cell populations. A growing body of studies have focused on the critical role of α6-containing integrins (α6β1 and α6β4) in the regulation of stem cell properties, lineage-specific differentiation, and niche interaction. α6-Integrin subunit can be alternatively spliced at the post-transcriptional level, giving rise to divergent isoforms which differ in the cytoplasmic and/or extracellular domains. The cytoplasmic domain of integrins is an important functional part of integrin-mediated signals. Structural changes in the cytoplasmic domain of α6 provide an efficient means for the regulation of stem cell responses to biochemical stimuli and/or biophysical cues in the stem cell niche, thus impacting stem cell fate determination. In this review, we summarize the current knowledge on the structural variants of the α6-integrin subunit and spatiotemporal expression of α6 cytoplasmic variants in embryonic and adult stem/progenitor cells. We highlight the roles of α6 cytoplasmic variants in stem cell fate decision and niche interaction, and discuss the potential mechanisms involved. Understanding of the distinct functions of α6 splicing variants in stem cell biology may inform the rational design of novel stem cell-based therapies for a range of human diseases.

Skin Stem Cell Hypotheses and Long Term Clone Survival – Explored Using Agent-based Modelling

PubMed Central

Li, X.; Upadhyay, A. K.; Bullock, A. J.; Dicolandrea, T.; Xu, J.; Binder, R. L.; Robinson, M. K.; Finlay, D. R.; Mills, K. J.; Bascom, C. C.; Kelling, C. K.; Isfort, R. J.; Haycock, J. W.; MacNeil, S.; Smallwood, R. H.

2013-01-01

Epithelial renewal in skin is achieved by the constant turnover and differentiation of keratinocytes. Three popular hypotheses have been proposed to explain basal keratinocyte regeneration and epidermal homeostasis: 1) asymmetric division (stem-transit amplifying cell); 2) populational asymmetry (progenitor cell with stochastic fate); and 3) populational asymmetry with stem cells. In this study, we investigated lineage dynamics using these hypotheses with a 3D agent-based model of the epidermis. The model simulated the growth and maintenance of the epidermis over three years. The offspring of each proliferative cell was traced. While all lineages were preserved in asymmetric division, the vast majority were lost when assuming populational asymmetry. The third hypothesis provided the most reliable mechanism for self-renewal by preserving genetic heterogeneity in quiescent stem cells, and also inherent mechanisms for skin ageing and the accumulation of genetic mutation. PMID:23712735

Skin stem cell hypotheses and long term clone survival--explored using agent-based modelling.

PubMed

Li, X; Upadhyay, A K; Bullock, A J; Dicolandrea, T; Xu, J; Binder, R L; Robinson, M K; Finlay, D R; Mills, K J; Bascom, C C; Kelling, C K; Isfort, R J; Haycock, J W; MacNeil, S; Smallwood, R H

2013-01-01

Epithelial renewal in skin is achieved by the constant turnover and differentiation of keratinocytes. Three popular hypotheses have been proposed to explain basal keratinocyte regeneration and epidermal homeostasis: 1) asymmetric division (stem-transit amplifying cell); 2) populational asymmetry (progenitor cell with stochastic fate); and 3) populational asymmetry with stem cells. In this study, we investigated lineage dynamics using these hypotheses with a 3D agent-based model of the epidermis. The model simulated the growth and maintenance of the epidermis over three years. The offspring of each proliferative cell was traced. While all lineages were preserved in asymmetric division, the vast majority were lost when assuming populational asymmetry. The third hypothesis provided the most reliable mechanism for self-renewal by preserving genetic heterogeneity in quiescent stem cells, and also inherent mechanisms for skin ageing and the accumulation of genetic mutation.

Prospects of Pluripotent and Adult Stem Cells for Rare Diseases.

PubMed

García-Castro, Javier; Singeç, Ilyas

2017-01-01

Rare diseases are highly diverse and complex regarding molecular underpinning and clinical manifestation and afflict millions of patients worldwide. The lack of appropriate model systems with face and construct validity and the limited availability of live tissues and cells from patients has largely hampered the understanding of underlying disease mechanisms. As a consequence, there are no adequate treatment options available for the vast majority of rare diseases. Over the last decade, remarkable progress in pluripotent and adult stem cell biology and the advent of powerful genomic technologies opened up exciting new avenues for the investigation, diagnosis, and personalized therapy of intractable human diseases. Utilizing the entire range of available stem cell types will continue to cross-fertilize different research areas and leverage the investigation of rare diseases based on evidence-based medicine. Standardized cell engineering and manufacturing from inexhaustible stem cell sources should lay the foundation for next-generation drug discovery and cell therapies that are broadly applicable in regenerative medicine. In this chapter we discuss how patient- and disease-specific iPS cells as well as adult stem cells are changing the pace of biomedical research and the translational landscape.

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.

The Ethics of Stem Cell-Based Aesthetic Surgery: Attitudes and Perceptions of the Plastic Surgery Community.

PubMed

Nayar, Harry S; Caplan, Arthur L; Eaves, Felmont F; Rubin, J Peter

2014-08-01

The emerging field of stem cell-based aesthetics has raised ethical concerns related to advertising campaigns and standards for safety and efficacy. The authors sought to characterize the attitudes of plastic surgeons regarding the ethics of stem cell-based aesthetics. A cross-sectional electronic survey was distributed to 4592 members of the American Society for Aesthetic Plastic Surgery and the American Society of Plastic Surgeons. Statements addressed ethical concerns about informed consent, conflicts of interest, advertising, regulation, and stem cell tourism. An agreement score (AS) from 0 to 100 was calculated for each statement. Majority agreement was designated as ≥60 and majority disagreement as ≤40. A total of 770 questionnaires were received (16.7%). The majority of respondents indicated that knowledge regarding the risks and benefits of stem cell procedures is insufficient to obtain valid informed consent (AS, 29) and that direct-to-consumer advertising for these technologies is inappropriate and unethical (AS, 23). Most respondents reported that patients should be actively warned against traveling abroad to receive aesthetic cell therapies (AS, 86) and that registries and evaluations of these clinics should be made publicly available (AS, 71). Even more respondents noted that financial conflicts of interest should be disclosed to patients (AS, 96) and that professional societies should participate in establishing regulatory standards (AS, 93). The plastic surgeons surveyed in this study support a well-regulated, evidence-based approach to aesthetic procedures involving stem cells. © 2014 The American Society for Aesthetic Plastic Surgery, Inc.

Retracted article: In vitro derivation of mammalian germ cells from stem cells and their potential therapeutic application.

PubMed

Saito, Shigeo; Lin, Ying-Chu; Murayama, Yoshinobu; Nakamura, Yukio; Eckner, Richard; Niemann, Heiner; Yokoyama, Kazunari K

2015-12-01

Pluripotent stem cells (PSCs) are a unique type of cells because they exhibit the characteristics of self-renewal and pluripotency. PSCs may be induced to differentiate into any cell type, even male and female germ cells, suggesting their potential as novel cell-based therapeutic treatment for infertility problems. Spermatogenesis is an intricate biological process that starts from self-renewal of spermatogonial stem cells (SSCs) and leads to differentiated haploid spermatozoa. Errors at any stage in spermatogenesis may result in male infertility. During the past decade, much progress has been made in the derivation of male germ cells from various types of progenitor stem cells. Currently, there are two main approaches for the derivation of functional germ cells from PSCs, either the induction of in vitro differentiation to produce haploid cell products, or combination of in vitro differentiation and in vivo transplantation. The production of mature and fertile spermatozoa from stem cells might provide an unlimited source of autologous gametes for treatment of male infertility. Here, we discuss the current state of the art regarding the differentiation potential of SSCs, embryonic stem cells, and induced pluripotent stem cells to produce functional male germ cells. We also discuss the possible use of livestock-derived PSCs as a novel option for animal reproduction and infertility treatment.

Variability of human pluripotent stem cell lines.

PubMed

Ortmann, Daniel; Vallier, Ludovic

2017-10-01

Human pluripotent stem cells derived from embryos (human Embryonic Stem Cells or hESCs) or generated by direct reprogramming of somatic cells (human Induced Pluripotent Stem Cells or hiPSCs) can proliferate almost indefinitely in vitro while maintaining the capacity to differentiate into a broad diversity of cell types. These two properties (self-renewal and pluripotency) confers human pluripotent stem cells a unique interest for clinical applications since they could allow the production of infinite quantities of cells for disease modelling, drug screening and cell based therapy. However, recent studies have clearly established that human pluripotent stem cell lines can display variable capacity to differentiate into specific lineages. Consequently, the development of universal protocols of differentiation which could work efficiently with any human pluripotent cell line is complicated substantially. As a consequence, each protocol needs to be adapted to every cell line thereby limiting large scale applications and precluding personalised therapies. Here, we summarise our knowledge concerning the origin of this variability and describe potential solutions currently available to bypass this major challenge. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

Stress-stiffening-mediated stem-cell commitment switch in soft responsive hydrogels

NASA Astrophysics Data System (ADS)

Das, Rajat K.; Gocheva, Veronika; Hammink, Roel; Zouani, Omar F.; Rowan, Alan E.

2016-03-01

Bulk matrix stiffness has emerged as a key mechanical cue in stem cell differentiation. Here, we show that the commitment and differentiation of human mesenchymal stem cells encapsulated in physiologically soft (~0.2-0.4 kPa), fully synthetic polyisocyanopeptide-based three-dimensional (3D) matrices that mimic the stiffness of adult stem cell niches and show biopolymer-like stress stiffening, can be readily switched from adipogenesis to osteogenesis by changing only the onset of stress stiffening. This mechanical behaviour can be tuned by simply altering the material’s polymer length whilst maintaining stiffness and ligand density. Our findings introduce stress stiffening as an important parameter that governs stem cell fate in a 3D microenvironment, and reveal a correlation between the onset of stiffening and the expression of the microtubule-associated protein DCAMKL1, thus implicating DCAMKL1 in a stress-stiffening-mediated, mechanotransduction pathway that involves microtubule dynamics in stem cell osteogenesis.

The potential role of adult stem cells in the management of the rheumatic diseases

PubMed Central

Franceschetti, Tiziana; De Bari, Cosimo

2017-01-01

Adult stem cells are considered as appealing therapeutic candidates for inflammatory and degenerative musculoskeletal diseases. A large body of preclinical research has contributed to describing their immune-modulating properties and regenerative potential. Additionally, increasing evidence suggests that stem cell differentiation and function are disrupted in the pathogenesis of rheumatic diseases. Clinical studies have been limited, for the most part, to the application of adult stem cell-based treatments on small numbers of patients or as a ‘salvage’ therapy in life-threatening disease cases. Nevertheless, these preliminary studies indicate that adult stem cells are promising tools for the long-term treatment of rheumatic diseases. This review highlights recent knowledge acquired in the fields of hematopoietic and mesenchymal stem cell therapy for the management of systemic sclerosis (SSc), systemic lupus erythematosus (SLE), rheumatoid arthritis (RA) and osteoarthritis (OA) and the potential mechanisms mediating their function. PMID:28717403

Evaluation of somatostatin and nucleolin receptors for therapeutic delivery in non-small cell lung cancer stem cells applying the somatostatin-analog DOTATATE and the nucleolin-targeting aptamer AS1411.

PubMed

Holmboe, Sif; Hansen, Pernille Lund; Thisgaard, Helge; Block, Ines; Müller, Carolin; Langkjær, Niels; Høilund-Carlsen, Poul Flemming; Olsen, Birgitte Brinkmann; Mollenhauer, Jan

2017-01-01

Cancer stem cells represent the putative tumor-driving subpopulation thought to account for drug resistance, relapse, and metastatic spread of epithelial and other cancer types. Accordingly, cell surface markers for therapeutic delivery to cancer stem cells are subject of intense research. Somatostatin receptor 2 and nucleolin are known to be overexpressed by various cancer types, which have elicited comprehensive efforts to explore their therapeutic utilization. Here, we evaluated somatostatin receptor 2 targeting and nucleolin targeting for therapeutic delivery to cancer stem cells from lung cancer. Nucleolin is expressed highly but not selectively, while somatostatin receptor 2 is expressed selectively but not highly by cancer cells. The non-small cell lung cancer cell lines A549 and H1299, displayed average levels of both surface molecules as judged based on analysis of a larger cell line panel. H1299 compared to A549 cells showed significantly elevated sphere-forming capacity, indicating higher cancer stem cell content, thus qualifying as suitable test system. Nucleolin-targeting 57Co-DOTA-AS1411 aptamer showed efficient internalization by cancer cells and, remarkably, at even higher efficiency by cancer stem cells. In contrast, somatostatin receptor 2 expression levels were not sufficiently high in H1299 cells to confer efficient uptake by either non-cancer stem cells or cancer stem cells. The data provides indication that the nucleolin-targeting AS1411 aptamer might be used for therapeutic delivery to non-small cell lung cancer stem cells.

Directing Stem Cell Differentiation via Electrochemical Reversible Switching between Nanotubes and Nanotips of Polypyrrole Array.

PubMed

Wei, Yan; Mo, Xiaoju; Zhang, Pengchao; Li, Yingying; Liao, Jingwen; Li, Yongjun; Zhang, Jinxing; Ning, Chengyun; Wang, Shutao; Deng, Xuliang; Jiang, Lei

2017-06-27

Control of stem cell behaviors at solid biointerfaces is critical for stem-cell-based regeneration and generally achieved by engineering chemical composition, topography, and stiffness. However, the influence of dynamic stimuli at the nanoscale from solid biointerfaces on stem cell fate remains unclear. Herein, we show that electrochemical switching of a polypyrrole (Ppy) array between nanotubes and nanotips can alter surface adhesion, which can strongly influence mechanotransduction activation and guide differentiation of mesenchymal stem cells (MSCs). The Ppy array, prepared via template-free electrochemical polymerization, can be reversibly switched between highly adhesive hydrophobic nanotubes and poorly adhesive hydrophilic nanotips through an electrochemical oxidation/reduction process, resulting in dynamic attachment and detachment to MSCs at the nanoscale. Multicyclic attachment/detachment of the Ppy array to MSCs can activate intracellular mechanotransduction and osteogenic differentiation independent of surface stiffness and chemical induction. This smart surface, permitting transduction of nanoscaled dynamic physical inputs into biological outputs, provides an alternative to classical cell culture substrates for regulating stem cell fate commitment. This study represents a general strategy to explore nanoscaled interactions between stem cells and stimuli-responsive surfaces.

Biological restoration of central nervous system architecture and function: part 3-stem cell- and cell-based applications and realities in the biological management of central nervous system disorders: traumatic, vascular, and epilepsy disorders.

PubMed

Farin, Azadeh; Liu, Charles Y; Langmoen, Iver A; Apuzzo, Michael L J

2009-11-01

STEM CELL THERAPY has emerged as a promising novel therapeutic endeavor for traumatic brain injury, spinal cord injury, stroke, and epilepsy in experimental studies. A few preliminary clinical trials have further supported its safety and early efficacy after transplantation into humans. Although not yet clinically available for central nervous system disorders, stem cell technology is expected to evolve into one of the most powerful tools in the biological management of complex central nervous system disorders, many of which currently have limited treatment modalities. The identification of stem cells, discovery of neurogenesis, and application of stem cells to treat central nervous system disorders represent a dramatic evolution and expansion of the neurosurgeon's capabilities into the neurorestoration and neuroregeneration realms. In Part 3 of a 5-part series on stem cells, we discuss the theory, experimental evidence, and clinical data pertaining to the use of stem cells for the treatment of traumatic, vascular, and epileptic disorders.

Usage of Human Mesenchymal Stem Cells in Cell-based Therapy: Advantages and Disadvantages.

PubMed

Kim, Hee Jung; Park, Jeong-Soo

2017-03-01

The use of human mesenchymal stem cells (hMSCs) in cell-based therapy has attracted extensive interest in the field of regenerative medicine, and it shows applications to numerous incurable diseases. hMSCs show several superior properties for therapeutic use compared to other types of stem cells. Different cell types are discussed in terms of their advantages and disadvantages, with focus on the characteristics of hMSCs. hMSCs can proliferate readily and produce differentiated cells that can substitute for the targeted affected tissue. To maximize the therapeutic effects of hMSCs, a substantial number of these cells are essential, requiring extensive ex vivo cell expansion. However, hMSCs have a limited lifespan in an in vitro culture condition. The senescence of hMSCs is a double-edged sword from the viewpoint of clinical applications. Although their limited cell proliferation potency protects them from malignant transformation after transplantation, senescence can alter various cell functions including proliferation, differentiation, and migration, that are essential for their therapeutic efficacy. Numerous trials to overcome the limited lifespan of mesenchymal stem cells are discussed.

Usage of Human Mesenchymal Stem Cells in Cell-based Therapy: Advantages and Disadvantages

PubMed Central

Kim, Hee Jung; Park, Jeong-Soo

2017-01-01

ABSTRACT The use of human mesenchymal stem cells (hMSCs) in cell-based therapy has attracted extensive interest in the field of regenerative medicine, and it shows applications to numerous incurable diseases. hMSCs show several superior properties for therapeutic use compared to other types of stem cells. Different cell types are discussed in terms of their advantages and disadvantages, with focus on the characteristics of hMSCs. hMSCs can proliferate readily and produce differentiated cells that can substitute for the targeted affected tissue. To maximize the therapeutic effects of hMSCs, a substantial number of these cells are essential, requiring extensive ex vivo cell expansion. However, hMSCs have a limited lifespan in an in vitro culture condition. The senescence of hMSCs is a double-edged sword from the viewpoint of clinical applications. Although their limited cell proliferation potency protects them from malignant transformation after transplantation, senescence can alter various cell functions including proliferation, differentiation, and migration, that are essential for their therapeutic efficacy. Numerous trials to overcome the limited lifespan of mesenchymal stem cells are discussed. PMID:28484739

Unique differentiation profile of mouse embryonic stem cells in rotary and stirred tank bioreactors.

PubMed

Fridley, Krista M; Fernandez, Irina; Li, Mon-Tzu Alice; Kettlewell, Robert B; Roy, Krishnendu

2010-11-01

Embryonic stem (ES)-cell-derived lineage-specific stem cells, for example, hematopoietic stem cells, could provide a potentially unlimited source for transplantable cells, especially for cell-based therapies. However, reproducible methods must be developed to maximize and scale-up ES cell differentiation to produce clinically relevant numbers of therapeutic cells. Bioreactor-based dynamic culture conditions are amenable to large-scale cell production, but few studies have evaluated how various bioreactor types and culture parameters influence ES cell differentiation, especially hematopoiesis. Our results indicate that cell seeding density and bioreactor speed significantly affect embryoid body formation and subsequent generation of hematopoietic stem and progenitor cells in both stirred tank (spinner flask) and rotary microgravity (Synthecon™) type bioreactors. In general, high percentages of hematopoietic stem and progenitor cells were generated in both bioreactors, especially at high cell densities. In addition, Synthecon bioreactors produced more sca-1(+) progenitors and spinner flasks generated more c-Kit(+) progenitors, demonstrating their unique differentiation profiles. cDNA microarray analysis of genes involved in pluripotency, germ layer formation, and hematopoietic differentiation showed that on day 7 of differentiation, embryoid bodies from both bioreactors consisted of all three germ layers of embryonic development. However, unique gene expression profiles were observed in the two bioreactors; for example, expression of specific hematopoietic genes were significantly more upregulated in the Synthecon cultures than in spinner flasks. We conclude that bioreactor type and culture parameters can be used to control ES cell differentiation, enhance unique progenitor cell populations, and provide means for large-scale production of transplantable therapeutic cells.

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.

Hematopoietic stem cell origin of connective tissues.

PubMed

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

2010-07-01

Connective tissue consists of "connective tissue proper," which is further divided into loose and dense (fibrous) connective tissues and "specialized connective tissues." Specialized connective tissues consist of blood, adipose tissue, cartilage, and bone. In both loose and dense connective tissues, the principal cellular element is fibroblasts. It has been generally believed that all cellular elements of connective tissue, including fibroblasts, adipocytes, chondrocytes, and bone cells, are generated solely by mesenchymal stem cells. Recently, a number of studies, including those from our laboratory based on transplantation of single hematopoietic stem cells, strongly suggested a hematopoietic stem cell origin of these adult mesenchymal tissues. This review summarizes the experimental evidence for this new paradigm and discusses its translational implications. Copyright 2010 ISEH - Society for Hematology and Stem Cells. All rights reserved.

A novel rat fibrosarcoma cell line from transformed bone marrow-derived mesenchymal stem cells with maintained in vitro and in vivo stemness properties.

PubMed

Wang, Meng-Yu; Nestvold, Janne; Rekdal, Øystein; Kvalheim, Gunnar; Fodstad, Øystein

2017-03-15

Increasing evidence suggests a possible relationship between mesenchymal stem cells (MSCs) and sarcoma. MSCs are hypothesized to be the cells initiating sarcomagenesis, and cancer stem cells (CSCs) sharing features of MSCs have been identified in sarcomas. Here, we report on the characteristics of a bone marrow-derived rat mesenchymal stem cell line that spontaneously transformed in long-term culture. The rat transformed mesenchymal stem cells (rTMSCs) produced soft-tissue fibrosarcomas in immunocompromised mice and immunocompetent rats. In vitro, the rTMSCs displayed increased proliferation capacity compared to the untransformed cell line. The transformed MSCs maintained the mesenchymal phenotype by expression of the stem cell marker CD 90 and the lack of hematopoietic and endothelial markers. Cytogenetic analysis detected trisomy 6 in the rTMSCs. Side population (SP) isolation and tumorsphere cultivation of the transformed cells confirmed the presence of CSCs among the rTMSCs. Importantly, the rTMSCs retained their differentiation capacity towards osteogenic and adipogenic lineages. This transformed MSC-based cell line may be valuable in examining the balance in a mixed cell population between cancer stem cell properties and the ability to differentiate to specific non-transformed cell populations. Moreover, it may also be a useful tool to evaluate the efficacy of novel targeted immunotherapies in vivo. Copyright © 2017 Elsevier Inc. All rights reserved.

Three-dimensional wet-electrospun poly(lactic acid)/multi-wall carbon nanotubes scaffold induces differentiation of human menstrual blood-derived stem cells into germ-like cells.

PubMed

Eyni, Hossein; Ghorbani, Sadegh; Shirazi, Reza; Salari Asl, Leila; P Beiranvand, Shahram; Soleimani, Masoud

2017-09-01

Infertility caused by the disruption or absence of germ cells is a major and largely incurable medical problem. Germ cells (i.e., sperm or egg) play a key role in the transmission of genetic and epigenetic information across generations. Generation of gametes derived in vitro from stem cells hold promising prospects which could potentially help infertile men and women. Menstrual blood-derived stem cells are a unique stem cell source. Evidence suggests that menstrual blood-derived stem cells exhibit a multi-lineage potential and have attracted extensive attention in regenerative medicine. To maintain the three-dimensional structure of natural extra cellular matrices in vitro, scaffolds can do this favor and mimic a microenvironment for cell proliferation and differentiation. According to previous studies, poly(lactic acid) and multi-wall carbon nanotubes have been introduced as novel and promising biomaterials for the proliferation and differentiation of stem cells. Some cell types have been successfully grown on a matrix containing carbon nanotubes in tissue engineering but there is no report for this material to support stem cells differentiation into germ cells lineage. This study designed a 3D wet-electrospun poly(lactic acid) and poly(lactic acid)/multi-wall carbon nanotubes composite scaffold to compare infiltration, proliferation, and differentiation potential of menstrual blood-derived stem cells toward germ cell lineage with 2D culture. Our primary data revealed that the fabricated scaffold has mechanical and biological suitable qualities for supporting and attachments of stem cells. The differentiated menstrual blood-derived stem cells tracking in scaffolds using scanning electron microscopy confirmed cell attachment, aggregation, and distribution on the porous scaffold. Based on the differentiation assay by RT-PCR analysis, stem cells and germ-like cells markers were expressed in 3D groups as well as 2D one. It seems that poly(lactic acid)/multi-wall carbon nanotubes scaffold-seeded menstrual blood-derived stem cells could be viewed as a novel, safe, and accessible construct for these cells, as they enhance germ-like generation from menstrual blood-derived stem cells.

Female mice lack adult germ-line stem cells but sustain oogenesis using stable primordial follicles.

PubMed

Lei, Lei; Spradling, Allan C

2013-05-21

Whether or not mammalian females generate new oocytes during adulthood from germ-line stem cells to sustain the ovarian follicle pool has recently generated controversy. We used a sensitive lineage-labeling system to determine whether stem cells are needed in female adult mice to compensate for follicular losses and to directly identify active germ-line stem cells. Primordial follicles generated during fetal life are highly stable, with a half-life during adulthood of 10 mo, and thus are sufficient to sustain adult oogenesis without a source of renewal. Moreover, in normal mice or following germ-cell depletion with Busulfan, only stable, single oocytes are lineage-labeled, rather than cell clusters indicative of new oocyte formation. Even one germ-line stem cell division per 2 wk would have been detected by our method, based on the kinetics of fetal follicle formation. Thus, adult female mice neither require nor contain active germ-line stem cells or produce new oocytes in vivo.

Personalized nanomedicine advancements for stem cell tracking☆

PubMed Central

Janowski, Mirek; Bulte, Jeff W.M.; Walczak, Piotr

2012-01-01

Recent technological developments in biomedicine have facilitated the generation of data on the anatomical, physiological and molecular level for individual patients and thus introduces opportunity for therapy to be personalized in an unprecedented fashion. Generation of patient-specific stem cells exemplifies the efforts toward this new approach. Cell-based therapy is a highly promising treatment paradigm; however, due to the lack of consistent and unbiased data about the fate of stem cells in vivo, interpretation of therapeutic remains challenging hampering the progress in this field. The advent of nanotechnology with a wide palette of inorganic and organic nanostructures has expanded the arsenal of methods for tracking transplanted stem cells. The diversity of nanomaterials has revolutionized personalized nanomedicine and enables individualized tailoring of stem cell labeling materials for the specific needs of each patient. The successful implementation of stem cell tracking will likely be a significant driving force that will contribute to the further development of nanotheranostics. The purpose of this review is to emphasize the role of cell tracking using currently available nanoparticles. PMID:22820528

Stem Cells Applications in Regenerative Medicine and Disease Therapeutics

PubMed Central

2016-01-01

Regenerative medicine, the most recent and emerging branch of medical science, deals with functional restoration of tissues or organs for the patient suffering from severe injuries or chronic disease. The spectacular progress in the field of stem cell research has laid the foundation for cell based therapies of disease which cannot be cured by conventional medicines. The indefinite self-renewal and potential to differentiate into other types of cells represent stem cells as frontiers of regenerative medicine. The transdifferentiating potential of stem cells varies with source and according to that regenerative applications also change. Advancements in gene editing and tissue engineering technology have endorsed the ex vivo remodelling of stem cells grown into 3D organoids and tissue structures for personalized applications. This review outlines the most recent advancement in transplantation and tissue engineering technologies of ESCs, TSPSCs, MSCs, UCSCs, BMSCs, and iPSCs in regenerative medicine. Additionally, this review also discusses stem cells regenerative application in wildlife conservation. PMID:27516776

Cell-based delivery of glucagon-like peptide-1 using encapsulated mesenchymal stem cells.

PubMed

Wallrapp, Christine; Thoenes, Eric; Thürmer, Frank; Jork, Anette; Kassem, Moustapha; Geigle, Peter

2013-01-01

Glucagon-like peptide-1 (GLP-1) CellBeads are cell-based implants for the sustained local delivery of bioactive factors. They consist of GLP-1 secreting mesenchymal stem cells encapsulated in a spherically shaped immuno-isolating alginate matrix. A highly standardized and reproducible encapsulation method is described for the manufacturing of homogeneous CellBeads. Viability and sustained secretion was shown for the recombinant GLP-1 and the cell endogenous bioactive factors like vascular endothelial growth factor, neurotrophin 3 (NT-3) and glial cell line-derived neurotrophic factor. Manufacturing and quality control is performed in compliance with good manufacturing practice and fulfils all regulatory requirements for human clinical use. GLP-1 CellBeads combine the neuro- and cardioprotective properties of both GLP-1 and mesenchymal stem cells. First promising results were obtained from preclinical studies and an ongoing safety trial in humans but further studies have to prove the overall potential of CellBead technology in cell-based regenerative medicine.

Microencapsulation of Hepatocytes and Mesenchymal Stem Cells for Therapeutic Applications.

PubMed

Meier, Raphael P H; Montanari, Elisa; Morel, Philippe; Pimenta, Joël; Schuurman, Henk-Jan; Wandrey, Christine; Gerber-Lemaire, Sandrine; Mahou, Redouan; Bühler, Leo H

2017-01-01

Encapsulated hepatocyte transplantation and encapsulated mesenchymal stem cell transplantation are newly developed potential treatments for acute and chronic liver diseases, respectively. Cells are microencapsulated in biocompatible semipermeable alginate-based hydrogels. Microspheres protect cells against antibodies and immune cells, while allowing nutrients, small/medium size proteins and drugs to diffuse inside and outside the polymer matrix. Microencapsulated cells are assessed in vitro and designed for experimental transplantation and for future clinical applications.Here, we describe the protocol for microencapsulation of hepatocytes and mesenchymal stem cells within hybrid poly(ethylene glycol)-alginate hydrogels.

XanoMatrix surfaces as scaffolds for mesenchymal stem cell culture and growth

PubMed Central

Bhardwaj, Garima; Webster, Thomas J

2016-01-01

Stem cells are being widely investigated for a wide variety of applications in tissue engineering due to their ability to differentiate into a number of cells such as neurons, osteoblasts, and fibroblasts. This ability of stem cells to differentiate into different types of cells is greatly based on mechanical and chemical cues received from their three-dimensional environments. All organs are formed by a number of cells linked together via an extracellular matrix (ECM). The ECM is a complex network of proteins and carbohydrates, which occupies intercellular spaces and regulates cellular activity by controlling cell adhesion, migration, proliferation, and differentiation. The ECM is composed of two main types of macromolecules, namely, polysaccharide glycosaminoglycans, which are covalently attached to proteins in the form of proteoglycans and fibrous proteins belonging to two functional groups, structural (collagen and elastin) and adhesive (fibronectin, laminin, vitronectin, etc). Tissue engineering is a multidisciplinary field that aims to develop biomimetic scaffolds that emulate properties of the ECM to help repair or regenerate diseased or damaged tissue. This study introduces one of these matrices, XanoMatrix, as an optimal scaffold for tissue engineering applications, in particular, for stem cell research, based on its composition, nanofibrous structure, and porosity. Results of this study suggest that XanoMatrix scaffolds are promising for stem cell tissue engineering applications and as improved cell culture inserts for studying stem cell functions (compared to traditional Corning and Falcon cell culture plates) and, thus, should be further studied. PMID:27354795

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.

Human adipose-derived stem cells promote vascularization of collagen-based scaffolds transplanted into nude mice

PubMed Central

Cherubino, Mario; Valdatta, Luigi; Balzaretti, Riccardo; Pellegatta, Igor; Rossi, Federica; Protasoni, Marina; Tedeschi, Alessandra; Accolla, Roberto S; Bernardini, Giovanni; Gornati, Rosalba

2016-01-01

Aim: After in vivo implantation of cell-loaded devices, only the cells close to the capillaries can obtain nutrients to maintain their functions. It is known that factors secreted by stem cells, rather than stem cells themselves, are fundamental to guarantee new vascularization in the area of implant. Materials & methods: To investigate this possibility, we have grafted mice with Bilayer and Flowable Integra® scaffolds, loaded or not with human adipose-derived stem cells. Results: Our results support the therapeutic potential of human adipose-derived stem cells to induce new vascular networks of engineered organs and tissues. Conclusion: This finding suggests that our approach can help to form new vascular networks that allow sufficient vascularization of engineered organs and tissues in cases of difficult wound healing due to ischemic conditions. PMID:26965659

Lgr5-EGFP marks taste bud stem/progenitor cells in posterior tongue

PubMed Central

Yee, Karen K.; Li, Yan; Redding, Kevin M.; Iwatsuki, Ken; Margolskee, Robert F.; Jiang, Peihua

2013-01-01

Until recently, reliable markers for adult stem cells have been lacking for many regenerative mammalian tissues. Lgr5 (leucine-rich repeat-containing G-protein coupled receptor 5) has been identified as a marker for adult stem cells in intestine, stomach, and hair follicle; Lgr5-expressing cells give rise to all types of cells in these tissues. Taste epithelium also regenerates constantly, yet the identity of adult taste stem cells remains elusive. In this study, we found that Lgr5 is strongly expressed in cells at the bottom of trench areas at the base of circumvallate and foliate taste papillae and weakly expressed in the basal area of taste buds and that Lgr5-expressing cells in posterior tongue are a subset of K14-positive epithelial cells. Lineage-tracing experiments using an inducible Cre knock-in allele in combination with Rosa26-LacZ and Rosa26-tdTomato reporter strains showed that Lgr5-expressing cells gave rise to taste cells, perigemmal cells, along with self-renewing cells at the bottom of trench areas at the base of circumvallate and foliate papillae. Moreover, using subtype-specific taste markers, we found that Lgr5-expressing cell progeny include all three major types of adult taste cells. Our results indicate that Lgr5 may mark adult taste stem or progenitor cells in the posterior portion of the tongue. PMID:23377989

Lgr5-EGFP marks taste bud stem/progenitor cells in posterior tongue.

PubMed

Yee, Karen K; Li, Yan; Redding, Kevin M; Iwatsuki, Ken; Margolskee, Robert F; Jiang, Peihua

2013-05-01

Until recently, reliable markers for adult stem cells have been lacking for many regenerative mammalian tissues. Lgr5 (leucine-rich repeat-containing G-protein-coupled receptor 5) has been identified as a marker for adult stem cells in intestine, stomach, and hair follicle; Lgr5-expressing cells give rise to all types of cells in these tissues. Taste epithelium also regenerates constantly, yet the identity of adult taste stem cells remains elusive. In this study, we found that Lgr5 is strongly expressed in cells at the bottom of trench areas at the base of circumvallate (CV) and foliate taste papillae and weakly expressed in the basal area of taste buds and that Lgr5-expressing cells in posterior tongue are a subset of K14-positive epithelial cells. Lineage-tracing experiments using an inducible Cre knockin allele in combination with Rosa26-LacZ and Rosa26-tdTomato reporter strains showed that Lgr5-expressing cells gave rise to taste cells, perigemmal cells, along with self-renewing cells at the bottom of trench areas at the base of CV and foliate papillae. Moreover, using subtype-specific taste markers, we found that Lgr5-expressing cell progeny include all three major types of adult taste cells. Our results indicate that Lgr5 may mark adult taste stem or progenitor cells in the posterior portion of the tongue. Copyright © 2013 AlphaMed Press.

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

PubMed Central

Holditch, Sara J.; Terzic, Andre

2014-01-01

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

Cell-based therapeutic strategies for multiple sclerosis.

PubMed

Scolding, Neil J; Pasquini, Marcelo; Reingold, Stephen C; Cohen, Jeffrey A

2017-11-01

The availability of multiple disease-modifying medications with regulatory approval to treat multiple sclerosis illustrates the substantial progress made in therapy of the disease. However, all are only partially effective in preventing inflammatory tissue damage in the central nervous system and none directly promotes repair. Cell-based therapies, including immunoablation followed by autologous haematopoietic stem cell transplantation, mesenchymal and related stem cell transplantation, pharmacologic manipulation of endogenous stem cells to enhance their reparative capabilities, and transplantation of oligodendrocyte progenitor cells, have generated substantial interest as novel therapeutic strategies for immune modulation, neuroprotection, or repair of the damaged central nervous system in multiple sclerosis. Each approach has potential advantages but also safety concerns and unresolved questions. Moreover, clinical trials of cell-based therapies present several unique methodological and ethical issues. We summarize here the status of cell-based therapies to treat multiple sclerosis and make consensus recommendations for future research and clinical trials. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain.

Abcg2 expression marks tissue-specific stem cells in multiple organs in a mouse progeny tracking model.

PubMed

Fatima, Soghra; Zhou, Sheng; Sorrentino, Brian P

2012-02-01

The side population phenotype is associated with the Hoechst dye efflux activity of the Abcg2 transporter and identifies hematopoietic stem cells (HSCs) in the bone marrow. This association suggests the direct use of Abcg2 expression to identify adult stem cells in various other organs. We have generated a lineage tracing mouse model based on an allele that coexpresses both Abcg2 and a CreERT2 expression cassette. By crossing these mice with lox-STOP-lox reporter lines (LacZ or YFP), cells that express Abcg2 and their progeny were identified following treatment with tamoxifen (Tam). In the liver and kidney, in which mature cells express Abcg2, reporter gene expression verified the expected physiologic expression pattern of the recombinant allele. Long-term marking of HSCs was seen in multiple peripheral blood lineages from adult mice, demonstrating that Abcg2(+) bone marrow HSCs contribute to steady-state hematopoiesis. Stem cell tracing patterns were seen in the small intestine and in seminiferous tubules in the testis 20 months after Tam treatment, proving that stem cells from these organs express Abcg2. Interstitial cells from skeletal and cardiac muscle were labeled, and some cells were costained with endothelial markers, raising the possibility that these cells may function in the repair response to muscle injury. Altogether, these studies prove that Abcg2 is a stem cell marker for blood, small intestine, testicular germ cells, and possibly for injured skeletal and/or cardiac muscle and provide a new model for studying stem cell activity that does not require transplant-based assays. Copyright © 2011 AlphaMed Press.

Developments in stem cell research and therapeutic cloning: Islamic ethical positions, a review.

PubMed

Fadel, Hossam E

2012-03-01

Stem cell research is very promising. The use of human embryos has been confronted with objections based on ethical and religious positions. The recent production of reprogrammed adult (induced pluripotent) cells does not - in the opinion of scientists - reduce the need to continue human embryonic stem cell research. So the debate continues. Islam always encouraged scientific research, particularly research directed toward finding cures for human disease. Based on the expectation of potential benefits, Islamic teachings permit and support human embryonic stem cell research. The majority of Muslim scholars also support therapeutic cloning. This permissibility is conditional on the use of supernumerary early pre-embryos which are obtained during infertility treatment in vitro fertilization (IVF) clinics. The early pre-embryos are considered in Islamic jurisprudence as worthy of respect but do not have the full sanctity offered to the embryo after implantation in the uterus and especially after ensoulment. In this paper the Islamic positions regarding human embryonic stem cell research and therapeutic cloning are reviewed in some detail, whereas positions in other religious traditions are mentioned only briefly. The status of human embryonic stem cell research and therapeutic cloning in different countries, including the USA and especially in Muslim countries, is discussed. © 2010 Blackwell Publishing Ltd.

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 happy destiny of frozen haematopoietic stem cells: from immature stem cells to mature applications.

PubMed

de Vries, E G E; Vellenga, E; Kluin-Nelemans, J C; Mulder, N H

2004-09-01

Forty years ago, van Putten described in the European Journal of Cancer (see this issue) quantitative studies on the optimal storage techniques of mouse and monkey bone marrow suspensions. Survival of the animals after irradiation following injection with stored bone marrow cell suspensions was the endpoint. He observed some species differences, but based on the data obtained considered a careful trial of the glycerol-polyvinylpyrrolide (PVP) combination for storage of marrow in man was indicated. In spite of this, dimethyl sulphoxide has become the 'standard' cryopreservant for human marrow stem cells. Over the last 40 years, there has been a tremendous increase in knowledge about haematopoietic stem cells and their use in the clinic. Haematopoietic stem cells are now known to travel between the bone marrow and peripheral blood and are the best-characterised adult stem cells. These cells are currently widely used for transplantations in the clinic and are obtained from a wide variety of sources. These include the bone marrow, peripheral blood, cord blood, autologous as well as allogeneic stem cells from related or unrelated donors. Increasingly, data has become available that adult haematopoietic stem cells can generate differentiated cells belonging to other cell types, a process called "developmental plasticity". Thus, they may contribute to non-haematopoietic tissue repair in multiple organ systems. This has created a whole new potential therapeutic armamentarium for the application of haematopoietic stem cells outside of the area of malignancies and haematopoietic disorders.

Key anticipated regulatory issues for clinical use of human induced pluripotent stem cells.

PubMed

Knoepfler, Paul S

2012-09-01

The production of human induced pluripotent stem cells (hiPSCs) has greatly expanded the realm of possible stem cell-based regenerative medicine therapies and has particularly exciting potential for autologous therapies. However, future therapies based on hiPSCs will first have to address not only similar regulatory issues as those facing human embryonic stem cells with the US FDA and international regulatory agencies, but also hiPSCs have raised unique concerns as well. While the first possible clinical use of hiPSCs remains down the road, as a field it would be wise for us to anticipate potential roadblocks and begin formulating solutions. In this article, I discuss the potential regulatory issues facing hiPSCs and propose some potential changes in the direction of the field in response.

Anti-thymocyte globulin as graft-versus-host disease prevention in the setting of allogeneic peripheral blood stem cell transplantation: a review from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation

PubMed Central

Baron, Frédéric; Mohty, Mohamad; Blaise, Didier; Socié, Gérard; Labopin, Myriam; Esteve, Jordi; Ciceri, Fabio; Giebel, Sebastian; Gorin, Norbert Claude; Savani, Bipin N; Schmid, Christoph; Nagler, Arnon

2017-01-01

Allogeneic hematopoietic stem cell transplantation is increasingly used as treatment for patients with life-threatening blood diseases. Its curative potential is largely based on immune-mediated graft-versus-leukemia effects caused by donor T cells contained in the graft. Unfortunately, donor T cells are also the cause of graft-versus-host disease. The vast majority of human leukocyte antigen-matched allogeneic hematopoietic stem cell transplants are nowadays carried out with peripheral blood stem cells as the stem cell source. In comparison with bone marrows, peripheral blood stem cells contain more hematopoietic stem/progenitor cells but also one log more T cells. Consequently, the use of peripheral blood stem cells instead of bone marrow has been associated with faster hematologic recovery and a lower risk of relapse in patients with advanced disease, but also with a higher incidence of chronic graft-versus-host disease. These observations have been the basis for several studies aimed at assessing the impact of immunoregulation with anti-thymocyte globulin on transplantation outcomes in patients given human leukocyte antigen-matched peripheral blood stem cells from related or unrelated donors. After a brief introduction on anti-thymocyte globulin, this article reviews recent studies assessing the impact of anti-thymocyte globulin on transplantation outcomes in patients given peripheral blood stem cells from human leukocyte antigen-matched related or unrelated donors as well as in recipients of grafts from human leukocyte antigen haploidentical donors. PMID:27927772

Generation of human induced pluripotent stem cells from urinary cells of a healthy donor using a non-integration system.

PubMed

Uhm, Kyung-Ok; Jo, Eun Hee; Go, Gue Youn; Kim, So-Jung; Choi, Hye Young; Im, Young Sam; Ha, Hye-Yeong; Jung, Ji-Won; Koo, Soo Kyung

2017-05-01

Urinary cells can be an ideal source for generating hiPSCs and progenitors, as they are easily accessible, non-invasive, and universally available. We generated human induced pluripotent stem cells (hiPSCs) from the urinary cells of a healthy donor using a Sendai virus-based gene delivery method. The generated hiPSC line, KSCBi001-A, has a normal karyotype (46,XY). The pluripotency and capacity of multilineage differentiation were characterized by comparison with those of a human embryonic stem cell line. This cell line is registered and available from National Stem Cell Bank, Korea National Institute of Health. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Pharmacologic and genetic strategies to enhance cell therapy for cardiac regeneration.

PubMed

Kanashiro-Takeuchi, Rosemeire M; Schulman, Ivonne Hernandez; Hare, Joshua M

2011-10-01

Cell-based therapy is emerging as an exciting potential therapeutic approach for cardiac regeneration following myocardial infarction (MI). As heart failure (HF) prevalence increases over time, development of new interventions designed to aid cardiac recovery from injury are crucial and should be considered more broadly. In this regard, substantial efforts to enhance the efficacy and safety of cell therapy are continuously growing along several fronts, including modifications to improve the reprogramming efficiency of inducible pluripotent stem cells (iPS), genetic engineering of adult stem cells, and administration of growth factors or small molecules to activate regenerative pathways in the injured heart. These interventions are emerging as potential therapeutic alternatives and/or adjuncts based on their potential to promote stem cell homing, proliferation, differentiation, and/or survival. Given the promise of therapeutic interventions to enhance the regenerative capacity of multipotent stem cells as well as specifically guide endogenous or exogenous stem cells into a cardiac lineage, their application in cardiac regenerative medicine should be the focus of future clinical research. This article is part of a special issue entitled "Key Signaling Molecules in Hypertrophy and Heart Failure." Copyright © 2011 Elsevier Ltd. All rights reserved.

Cancer stem cells in hepatocellular carcinoma: Therapeutic implications based on stem cell biology.

PubMed

Chiba, Tetsuhiro; Iwama, Atsushi; Yokosuka, Osamu

2016-01-01

Hepatocellular carcinoma (HCC) is the sixth most common cancer and the third most frequent cause of cancer-related death worldwide. Despite advances in its diagnosis and treatment, the prognosis of patients with advanced HCC remains unfavorable. Recent advances in stem cell biology and associated technologies have enabled the identification of minor components of tumorigenic cells, termed cancer stem cells (CSC) or tumor-initiating cells, in cancers such as HCC. Furthermore, because CSC play a central role in tumor development, metastasis and recurrence, they are considered to be a therapeutic target in cancer treatment. Hepatic CSC have been successfully identified using functional and cell surface markers. The analysis of purified hepatic CSC has revealed the molecular machinery and signaling pathways involved in their maintenance. In addition, epigenetic transcriptional regulation has been shown to be important in the development and maintenance of CSC. Although inhibitors of CSC show promise as CSC-targeting drugs, novel therapeutic approaches for the eradication of CSC are yet to be established. In this review, we describe recent progress in hepatic CSC research and provide a perspective on the available therapeutic approaches based on stem cell biology. © 2015 The Japan Society of Hepatology.

Engineering Concepts in Stem Cell Research.

PubMed

Narayanan, Karthikeyan; Mishra, Sachin; Singh, Satnam; Pei, Ming; Gulyas, Balazs; Padmanabhan, Parasuraman

2017-12-01

The field of regenerative medicine integrates advancements made in stem cells, molecular biology, engineering, and clinical methodologies. Stem cells serve as a fundamental ingredient for therapeutic application in regenerative medicine. Apart from stem cells, engineering concepts have equally contributed to the success of stem cell based applications in improving human health. The purpose of various engineering methodologies is to develop regenerative and preventive medicine to combat various diseases and deformities. Explosion of stem cell discoveries and their implementation in clinical setting warrants new engineering concepts and new biomaterials. Biomaterials, microfluidics, and nanotechnology are the major engineering concepts used for the implementation of stem cells in regenerative medicine. Many of these engineering technologies target the specific niche of the cell for better functional capability. Controlling the niche is the key for various developmental activities leading to organogenesis and tissue homeostasis. Biomimetic understanding not only helped to improve the design of the matrices or scaffolds by incorporating suitable biological and physical components, but also ultimately aided adoption of designs that helped these materials/devices have better function. Adoption of engineering concepts in stem cell research improved overall achievement, however, several important issues such as long-term effects with respect to systems biology needs to be addressed. Here, in this review the authors will highlight some interesting breakthroughs in stem cell biology that use engineering methodologies. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

EZ spheres: a stable and expandable culture system for the generation of pre-rosette multipotent stem cells from human ESCs and iPSCs.

PubMed

Ebert, Allison D; Shelley, Brandon C; Hurley, Amanda M; Onorati, Marco; Castiglioni, Valentina; Patitucci, Teresa N; Svendsen, Soshana P; Mattis, Virginia B; McGivern, Jered V; Schwab, Andrew J; Sareen, Dhruv; Kim, Ho Won; Cattaneo, Elena; Svendsen, Clive N

2013-05-01

We have developed a simple method to generate and expand multipotent, self-renewing pre-rosette neural stem cells from both human embryonic stem cells (hESCs) and human induced pluripotent stem cells (iPSCs) without utilizing embryoid body formation, manual selection techniques, or complex combinations of small molecules. Human ESC and iPSC colonies were lifted and placed in a neural stem cell medium containing high concentrations of EGF and FGF-2. Cell aggregates (termed EZ spheres) could be expanded for long periods using a chopping method that maintained cell-cell contact. Early passage EZ spheres rapidly down-regulated OCT4 and up-regulated SOX2 and nestin expression. They retained the potential to form neural rosettes and consistently differentiated into a range of central and peripheral neural lineages. Thus, they represent a very early neural stem cell with greater differentiation flexibility than other previously described methods. As such, they will be useful for the rapidly expanding field of neurological development and disease modeling, high-content screening, and regenerative therapies based on pluripotent stem cell technology. Copyright © 2013 Elsevier B.V. All rights reserved.

Hematopoietic and mesenchymal stem cells for the treatment of chronic respiratory diseases: role of plasticity and heterogeneity.

PubMed

Conese, Massimo; Piro, Donatella; Carbone, Annalucia; Castellani, Stefano; Di Gioia, Sante

2014-01-01

Chronic lung diseases, such as cystic fibrosis (CF), asthma, and chronic obstructive pulmonary disease (COPD) are incurable and represent a very high social burden. Stem cell-based treatment may represent a hope for the cure of these diseases. In this paper, we revise the overall knowledge about the plasticity and engraftment of exogenous marrow-derived stem cells into the lung, as well as their usefulness in lung repair and therapy of chronic lung diseases. The lung is easily accessible and the pathophysiology of these diseases is characterized by injury, inflammation, and eventually by remodeling of the airways. Bone marrow-derived stem cells, including hematopoietic stem/progenitor cells (HSPCs) and mesenchymal stromal (stem) cells (MSCs), encompass a wide array of cell subsets with different capacities of engraftment and injured tissue regenerating potential. Proof-of-principle that marrow cells administered locally may engraft and give rise to specialized epithelial cells has been given, but the efficiency of this conversion is too limited to give a therapeutic effect. Besides the identification of plasticity mechanisms, the characterization/isolation of the stem cell subpopulations represents a major challenge to improving the efficacy of transplantation protocols used in regenerative medicine for lung diseases.

An efficient and scalable pipeline for epitope tagging in mammalian stem cells using Cas9 ribonucleoprotein

PubMed Central

Dewari, Pooran Singh; Southgate, Benjamin; Mccarten, Katrina; Monogarov, German; O'Duibhir, Eoghan; Quinn, Niall; Tyrer, Ashley; Leitner, Marie-Christin; Plumb, Colin; Kalantzaki, Maria; Blin, Carla; Finch, Rebecca; Bressan, Raul Bardini; Morrison, Gillian; Jacobi, Ashley M; Behlke, Mark A; von Kriegsheim, Alex; Tomlinson, Simon; Krijgsveld, Jeroen

2018-01-01

CRISPR/Cas9 can be used for precise genetic knock-in of epitope tags into endogenous genes, simplifying experimental analysis of protein function. However, Cas9-assisted epitope tagging in primary mammalian cell cultures is often inefficient and reliant on plasmid-based selection strategies. Here, we demonstrate improved knock-in efficiencies of diverse tags (V5, 3XFLAG, Myc, HA) using co-delivery of Cas9 protein pre-complexed with two-part synthetic modified RNAs (annealed crRNA:tracrRNA) and single-stranded oligodeoxynucleotide (ssODN) repair templates. Knock-in efficiencies of ~5–30%, were achieved without selection in embryonic stem (ES) cells, neural stem (NS) cells, and brain-tumor-derived stem cells. Biallelic-tagged clonal lines were readily derived and used to define Olig2 chromatin-bound interacting partners. Using our novel web-based design tool, we established a 96-well format pipeline that enabled V5-tagging of 60 different transcription factors. This efficient, selection-free and scalable epitope tagging pipeline enables systematic surveys of protein expression levels, subcellular localization, and interactors across diverse mammalian stem cells. PMID:29638216

Agonism of Wnt/β-catenin signaling promotes mesenchymal stem cell (MSC) expansion

PubMed Central

Hoffman, Michael D.; Benoit, Danielle S.W.

2014-01-01

Promoting mesenchymal stem cell (MSC) proliferation has numerous applications in stem cell therapies, particularly in the area of regenerative medicine. In order for cell-based regenerative approaches to be realized, MSC proliferation must be achieved in a controlled manner without compromising stem cell differentiation capacities. Here we demonstrate that 6-bromoindirubin-3’-oxime (BIO) increases MSC β-catenin activity 106-fold and stem cell-associated gene expression ~33-fold respectively over untreated controls. Subsequently, BIO treatment increases MSC populations 1.8-fold in typical 2D culture conditions, as well as 1.3-fold when encapsulated within hydrogels compared to untreated cells. Furthermore, we demonstrate that BIO treatment does not reduce MSC multipotency, where MSCs maintain their ability to differentiate into osteoblasts, chondrocytes, and adipocytes using standard conditions. Taken together, our results demonstrate BIOs potential utility as a proliferative agent for cell transplantation and tissue regeneration. PMID:23554411

Hematopoietic Stem Cells in Regenerative Medicine: Astray or on the Path?

PubMed Central

Müller, Albrecht M.; Huppertz, Sascha; Henschler, Reinhard

2016-01-01

Hematopoietic stem cells (HSCs) are the best characterized adult stem cells and the only stem cell type in routine clinical use. The concept of stem cell transplantation laid the foundations for the development of novel cell therapies within, and even outside, the hematopoietic system. Here, we report on the history of hematopoietic cell transplantation (HCT) and of HSC isolation, we briefly summarize the capabilities of HSCs to reconstitute the entire hemato/lymphoid cell system, and we assess current indications for HCT. We aim to draw the lines between areas where HCT has been firmly established, areas where HCT can in the future be expected to be of clinical benefit using their regenerative functions, and areas where doubts persist. We further review clinical trials for diverse approaches that are based on HCT. Finally, we highlight the advent of genome editing in HSCs and critically view the use of HSCs in non-hematopoietic tissue regeneration. PMID:27721700

Ground-state transcriptional requirements for skin-derived precursors.

PubMed

Suflita, Michael T; Pfaltzgraff, Elise R; Mundell, Nathan A; Pevny, Larysa H; Labosky, Patricia A

2013-06-15

Skin-derived precursors (SKPs) are an attractive stem cell model for cell-based therapies. SKPs can be readily generated from embryonic and adult mice and adult humans, exhibit a high degree of multipotency, and have the potential to serve as a patient autologous stem cell. The advancement of these cells toward therapeutic use depends on the ability to control precisely the self-renewal and differentiation of SKPs. Here we show that two well-known stem cell factors, Foxd3 and Sox2, are critical regulators of the stem cell properties of SKPs. Deletion of Foxd3 completely abolishes the sphere-forming potential of these cells. In the absence of Sox2, SKP spheres can be formed, but with reduced size and frequency. Our results provide entry points into the gene regulatory networks dictating SKP behavior, and pave the way for future studies on a therapeutically relevant stem cell.

Ground-State Transcriptional Requirements for Skin-Derived Precursors

PubMed Central

Suflita, Michael T.; Pfaltzgraff, Elise R.; Mundell, Nathan A.; Pevny, Larysa H.

2013-01-01

Skin-derived precursors (SKPs) are an attractive stem cell model for cell-based therapies. SKPs can be readily generated from embryonic and adult mice and adult humans, exhibit a high degree of multipotency, and have the potential to serve as a patient autologous stem cell. The advancement of these cells toward therapeutic use depends on the ability to control precisely the self-renewal and differentiation of SKPs. Here we show that two well-known stem cell factors, Foxd3 and Sox2, are critical regulators of the stem cell properties of SKPs. Deletion of Foxd3 completely abolishes the sphere-forming potential of these cells. In the absence of Sox2, SKP spheres can be formed, but with reduced size and frequency. Our results provide entry points into the gene regulatory networks dictating SKP behavior, and pave the way for future studies on a therapeutically relevant stem cell. PMID:23316968

Functional significance of CD105-positive cells in papillary renal cell carcinoma.

PubMed

Matak, Damian; Brodaczewska, Klaudia K; Szczylik, Cezary; Koch, Irena; Myszczyszyn, Adam; Lipiec, Monika; Lewicki, Slawomir; Szymanski, Lukasz; Zdanowski, Robert; Czarnecka, Anna M

2017-01-05

CD105 was postulated as a renal cell carcinoma (RCC) stem cell marker, and CD133 as a putative RCC progenitor. Hypoxia, a natural microenvironment that prevails in tumors, was also incorporated into the study, especially in terms of the promotion of hypothetical stem-like cell properties. Within this study, we verify the existence of CD105+ and CD133+ populations in selected papillary subtype RCC (pRCC) cell lines. Both populations were analyzed for correlation with stem-like cell properties, such as stemness gene expression, and sphere and colony formation. For the preliminary analysis, several RCC cell lines were chosen (786-O, SMKT-R2, Caki-2, 796-P, ACHN, RCC6) and the control was human kidney cancer stem cells (HKCSC) and renal cells of embryonic origin (ASE-5063). Four cell lines were chosen for further investigation: Caki-2 (one of the highest numbers of CD105+ cells; primary origin), ACHN (a low number of CD105+ cells; metastatic origin), HKCSC (putative positive control), and ASE-5063 (additional control). In 769-P and RCC6, we could not detect a CD105+ population. Hypoxia variously affects pRCC cell growth, and mainly diminishes the stem-like properties of cells. Furthermore, we could not observe the correlation of CD105 and/or CD133 expression with the enhancement of stem-like properties. Based on this analysis, CD105/CD133 cannot be validated as cancer stem cell markers of pRCC cell lines.

Fluorescent labelling of intestinal epithelial cells reveals independent long-lived intestinal stem cells in a crypt

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

Horita, Nobukatsu; Tsuchiya, Kiichiro, E-mail: kii.gast@tmd.ac.jp; Hayashi, Ryohei

Highlights: • Lentivirus mixed with Matrigel enables direct infection of intestinal organoids. • Our original approach allows the marking of a single stem cell in a crypt. • Time-lapse imaging shows the dynamics of a single stem cell. • Our lentivirus transgene system demonstrates plural long-lived stem cells in a crypt. - Abstract: Background and aims: The dynamics of intestinal stem cells are crucial for regulation of intestinal function and maintenance. Although crypt stem cells have been identified in the intestine by genetic marking methods, identification of plural crypt stem cells has not yet been achieved as they are visualisedmore » in the same colour. Methods: Intestinal organoids were transferred into Matrigel® mixed with lentivirus encoding mCherry. The dynamics of mCherry-positive cells was analysed using time-lapse imaging, and the localisation of mCherry-positive cells was analysed using 3D immunofluorescence. Results: We established an original method for the introduction of a transgene into an organoid generated from mouse small intestine that resulted in continuous fluorescence of the mCherry protein in a portion of organoid cells. Three-dimensional analysis using confocal microscopy showed a single mCherry-positive cell in an organoid crypt that had been cultured for >1 year, which suggested the presence of long-lived mCherry-positive and -negative stem cells in the same crypt. Moreover, a single mCherry-positive stem cell in a crypt gave rise to both crypt base columnar cells and transit amplifying cells. Each mCherry-positive and -negative cell contributed to the generation of organoids. Conclusions: The use of our original lentiviral transgene system to mark individual organoid crypt stem cells showed that long-lived plural crypt stem cells might independently serve as intestinal epithelial cells, resulting in the formation of a completely functional villus.« less

Stem Cells and Healing: Impact on Inflammation

PubMed Central

Ennis, William J.; Sui, Audrey; Bartholomew, Amelia

2013-01-01

Significance The number of patients with nonhealing wounds has rapidly accelerated over the past 10 years in both the United States and worldwide. Some causative factors at the macro level include an aging population, epidemic numbers of obese and diabetic patients, and an increasing number of surgical procedures. At the micro level, chronic inflammation is a consistent finding. Recent Advances A number of treatment modalities are currently used to accelerate wound healing, including energy-based modalities, scaffoldings, the use of mechano-transduction, cytokines/growth factors, and cell-based therapies. The use of stem cell therapy has been hypothesized as a potentially useful adjunct for nonhealing wounds. Specifically, mesenchymal stem cells (MSCs) have been shown to improve wound healing in several studies. Immune modulating properties of MSCs have made them attractive treatment options. Critical Issues Current limitations of stem cell therapy include the potentially large number of cells required for an effect, complex preparation and delivery methods, and poor cell retention in targeted tissues. Comparisons of published in-vitro and clinical trials are difficult due to cell preparation techniques, passage number, and the impact of the micro-environment on cell behavior. Future Directions MSCs may be more useful if they are preactivated with inflammatory cytokines such as tumor necrosis factor alpha or interferon gamma. This article will review the current literature with regard to the use of stem cells for wound healing. In addition the anti-inflammatory effects of MSCs will be discussed along with the potential benefits of stem cell preactivation. PMID:24587974

PLURIPOTENT STEM CELL APPLICATIONS FOR REGENERATIVE MEDICINE

PubMed Central

Angelos, Mathew G.; Kaufman, Dan S.

2015-01-01

Purpose of Review In this review, we summarize the current status of clinical trials using therapeutic cells produced from human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs). We also discuss combined cell and gene therapy via correction of defined mutations in human pluripotent stem cells and provide commentary on key obstacles facing wide-scale clinical adoption of pluripotent stem cell-based therapy. Recent Findings Initial data suggest hESC/hiPSC-derived cell products used for retinal repair and spinal cord injury are safe for human use. Early stage studies for treatment of cardiac injury and diabetes are also in progress. However, there remain key concerns regarding the safety and efficacy of these cells that need to be addressed in additional well-designed clinical trials. Advances using the CRISPR/Cas9 gene-editing system offer an improved tool for more rapid and on-target gene correction of genetic diseases. Combined gene and cell therapy using human pluripotent stem cells may provide an additional curative approach for disabling or lethal genetic and degenerative diseases where there are currently limited therapeutic opportunities. Summary Human pluripotent stem cells are emerging as a promising tool to produce cells and tissues suitable for regenerative therapy for a variety of genetic and degenerative diseases. PMID:26536430

Imaging approaches for the study of cell based cardiac therapies

PubMed Central

Lau, Joe F.; Anderson, Stasia A.; Adler, Eric; Frank, Joseph A.

2009-01-01

Despite promising preclinical data, the treatment of cardiovascular diseases using embryonic, bone-marrow-derived, and skeletal myoblast stem cells has not yet come to fruition within mainstream clinical practice. Major obstacles in cardiac stem cell investigations include the ability to monitor cell engraftment and survival following implantation within the myocardium. Several cellular imaging modalities, including reporter gene and MRI-based tracking approaches, have emerged that provide the means to identify, localize and monitor stem cells longitudinally in vivo following implantation. This Review will examine the various cardiac cellular tracking modalities, including the combinatorial use of several probes in multimodality imaging, with a focus on data from the last five years. PMID:20027188

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.

The immune boundaries for stem cell based therapies: problems and prospective solutions

PubMed Central

Abdelkrim, Hmadcha; Juan, Domínguez-Bendala; Jane, Wakeman; Mohamed, Arredouani; Bernat, Soria

2009-01-01

Stem cells have fascinated the scientific and clinical communities for over a century. Despite the controversy that surrounds this field, it is clear that stem cells have the potential to revolutionize medicine. However, a number of significant hurdles still stand in the way of the realization of this potential. Chiefly among these are safety concerns, differentiation efficiency and overcoming immune rejection. Here we review current progress made in this field to optimize the safe use of stem cells with particular emphasis on prospective interventions to deal with challenges generated by immune rejection. PMID:19583810

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

PubMed

Huysseune, Ann; Thesleff, Irma

2004-06-01

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

Successful isolation of viable adipose-derived stem cells from human adipose tissue subject to long-term cryopreservation: positive implications for adult stem cell-based therapeutics in patients of advanced age.

PubMed

Devitt, Sean M; Carter, Cynthia M; Dierov, Raia; Weiss, Scott; Gersch, Robert P; Percec, Ivona

2015-01-01

We examined cell isolation, viability, and growth in adipose-derived stem cells harvested from whole adipose tissue subject to different cryopreservation lengths (2-1159 days) from patients of varying ages (26-62 years). Subcutaneous abdominal adipose tissue was excised during abdominoplasties and was cryopreserved. The viability and number of adipose-derived stem cells isolated were measured after initial isolation and after 9, 18, and 28 days of growth. Data were analyzed with respect to cryopreservation duration and patient age. Significantly more viable cells were initially isolated from tissue cryopreserved <1 year than from tissue cryopreserved >2 years, irrespective of patient age. However, this difference did not persist with continued growth and there were no significant differences in cell viability or growth at subsequent time points with respect to cryopreservation duration or patient age. Mesenchymal stem cell markers were maintained in all cohorts tested throughout the duration of the study. Consequently, longer cryopreservation negatively impacts initial live adipose-derived stem cell isolation; however, this effect is neutralized with continued cell growth. Patient age does not significantly impact stem cell isolation, viability, or growth. Cryopreservation of adipose tissue is an effective long-term banking method for isolation of adipose-derived stem cells in patients of varying ages.

Glioma-associated stem cells: a novel class of tumor-supporting cells able to predict prognosis of human low-grade gliomas.

PubMed

Bourkoula, Evgenia; Mangoni, Damiano; Ius, Tamara; Pucer, Anja; Isola, Miriam; Musiello, Daniela; Marzinotto, Stefania; Toffoletto, Barbara; Sorrentino, Marisa; Palma, Anita; Caponnetto, Federica; Gregoraci, Giorgia; Vindigni, Marco; Pizzolitto, Stefano; Falconieri, Giovanni; De Maglio, Giovanna; Pecile, Vanna; Ruaro, Maria Elisabetta; Gri, Giorgia; Parisse, Pietro; Casalis, Loredana; Scoles, Giacinto; Skrap, Miran; Beltrami, Carlo Alberto; Beltrami, Antonio Paolo; Cesselli, Daniela

2014-05-01

Translational medicine aims at transferring advances in basic science research into new approaches for diagnosis and treatment of diseases. Low-grade gliomas (LGG) have a heterogeneous clinical behavior that can be only partially predicted employing current state-of-the-art markers, hindering the decision-making process. To deepen our comprehension on tumor heterogeneity, we dissected the mechanism of interaction between tumor cells and relevant components of the neoplastic environment, isolating, from LGG and high-grade gliomas (HGG), proliferating stem cell lines from both the glioma stroma and, where possible, the neoplasm. We isolated glioma-associated stem cells (GASC) from LGG (n=40) and HGG (n=73). GASC showed stem cell features, anchorage-independent growth, and supported the malignant properties of both A172 cells and human glioma-stem cells, mainly through the release of exosomes. Finally, starting from GASC obtained from HGG (n=13) and LGG (n=12) we defined a score, based on the expression of 9 GASC surface markers, whose prognostic value was assayed on 40 subsequent LGG-patients. At the multivariate Cox analysis, the GASC-based score was the only independent predictor of overall survival and malignant progression free-survival. The microenvironment of both LGG and HGG hosts non-tumorigenic multipotent stem cells that can increase in vitro the biological aggressiveness of glioma-initiating cells through the release of exosomes. The clinical importance of this finding is supported by the strong prognostic value associated with the characteristics of GASC. This patient-based approach can provide a groundbreaking method to predict prognosis and to exploit novel strategies that target the tumor stroma. © 2013 AlphaMed Press.

Stem cell isolation by a morphology-based selection method in postnatal mouse ovary.

PubMed

Parvari, Soraya; Abbasi, Mehdi; Abbasi, Niloufar; Malek, Valliollah Gerayeli; Amidi, Fardin; Aval, Fereydoon Sargolzaei; Roudkenar, Mehryar Habibi; Izadyar, Fariburz

2015-06-19

An increasing body of evidence has emerged regarding the existence and function of spermatogonial stem cells (SSCs); however, their female counterparts are the subject of extensive debate. Theoretically, ovarian germ stem cells (GSCs) have to reside in the murine ovary to support and replenish the follicle pool during the reproductive life span. Recently, various methods have been recruited to isolate and describe aspects of ovarian GSCs, but newer and more convenient strategies in isolation are still growing. Herein, a morphology-based method was used to isolate GSCs. A cell suspension of mouse neonatal ovaries was cultured. Colonies of GSCs were harvested mechanically and cultivated on mouse embryonic fibroblasts (MEF). Alkaline phosphatase activity was assessed to verify stemness features of cells in colonies. Expression of germ and stem cell specific genes (Oct-4, Nanog, Fragilis, C-kit, Dazl, and Mvh) was analyzed by reverse transcription-polymerase chain reaction (RT-PCR). Immunofluorescence of Oct4, Dazl, Mvh, and SSEA-1 was also performed. Small colonies without a clear border appeared during the first 4 days of culture, and the size of colonies increased rapidly. Cells in colonies were positive for alkaline phosphatase activity. Reverse transcription-polymerase chain reaction showed that Oct-4, Fragilis, C-kit, Nanog, Mvh, and Dazl were expressed in colony-forming cells. Immunofluorescence revealed a positive signal for Oct4, Dazl, Mvh, and SSEA-1 in colonies as well. The applicability of morphological selection for isolation of GSCs was verified. This method is easier and more economical than other techniques. The availability of ovarian stem cells can motivate further studies in development of oocyte and cell-based therapies.

Stem cell isolation by a morphology-based selection method in postnatal mouse ovary

PubMed Central

Parvari, Soraya; Abbasi, Niloufar; Malek, Valliollah Gerayeli; Amidi, Fardin; Aval, Fereydoon Sargolzaei; Roudkenar, Mehryar Habibi; Izadyar, Fariburz

2015-01-01

Introduction An increasing body of evidence has emerged regarding the existence and function of spermatogonial stem cells (SSCs); however, their female counterparts are the subject of extensive debate. Theoretically, ovarian germ stem cells (GSCs) have to reside in the murine ovary to support and replenish the follicle pool during the reproductive life span. Recently, various methods have been recruited to isolate and describe aspects of ovarian GSCs, but newer and more convenient strategies in isolation are still growing. Herein, a morphology-based method was used to isolate GSCs. Material and methods A cell suspension of mouse neonatal ovaries was cultured. Colonies of GSCs were harvested mechanically and cultivated on mouse embryonic fibroblasts (MEF). Alkaline phosphatase activity was assessed to verify stemness features of cells in colonies. Expression of germ and stem cell specific genes (Oct-4, Nanog, Fragilis, C-kit, Dazl, and Mvh) was analyzed by reverse transcription-polymerase chain reaction (RT-PCR). Immunofluorescence of Oct4, Dazl, Mvh, and SSEA-1 was also performed. Results Small colonies without a clear border appeared during the first 4 days of culture, and the size of colonies increased rapidly. Cells in colonies were positive for alkaline phosphatase activity. Reverse transcription-polymerase chain reaction showed that Oct-4, Fragilis, C-kit, Nanog, Mvh, and Dazl were expressed in colony-forming cells. Immunofluorescence revealed a positive signal for Oct4, Dazl, Mvh, and SSEA-1 in colonies as well. Conclusions The applicability of morphological selection for isolation of GSCs was verified. This method is easier and more economical than other techniques. The availability of ovarian stem cells can motivate further studies in development of oocyte and cell-based therapies. PMID:26170863

Stem Cells for Osteochondral Regeneration.

PubMed

Canadas, Raphaël F; Pirraco, Rogério P; Oliveira, J Miguel; Reis, Rui L; Marques, Alexandra P

2018-01-01

Stem cell research plays a central role in the future of medicine, which is mainly dependent on the advances on regenerative medicine (RM), specifically in the disciplines of tissue engineering (TE) and cellular therapeutics. All RM strategies depend upon the harnessing, stimulation, or guidance of endogenous developmental or repair processes in which cells have an important role. Among the most clinically challenging disorders, cartilage degeneration, which also affects subchondral bone becoming an osteochondral (OC) defect, is one of the most demanding. Although primary cells have been clinically applied, stem cells are currently seen as the promising tool of RM-related research because of its availability, in vitro proliferation ability, pluri- or multipotency, and immunosuppressive features. Being the OC unit, a transition from the bone to cartilage, mesenchymal stem cells (MSCs) are the main focus for OC regeneration. Promising alternatives, which can also be obtained from the patient or at banks and have great differentiation potential toward a wide range of specific cell types, have been reported. Still, ethical concerns and tumorigenic risk are currently under discussion and assessment. In this book chapter, we revise the existing stem cell-based approaches for engineering bone and cartilage, focusing on cell therapy and TE. Furthermore, 3D OC composites based on cell co-cultures are described. Finally, future directions and challenges still to be faced are critically discussed.

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

PubMed Central

Mimeault, M; Batra, S K

2010-01-01

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

Embryonic Stem Cell-Based Cardiopatches Improve Cardiac Function in Infarcted Rats

PubMed Central

Vallée, Jean-Paul; Hauwel, Mathieu; Lepetit-Coiffé, Matthieu; Bei, Wang; Montet-Abou, Karin; Meda, Paolo; Gardier, Stephany; Zammaretti, Prisca; Kraehenbuehl, Thomas P.; Herrmann, Francois; Hubbell, Jeffrey A.

2012-01-01

Pluripotent stem cell-seeded cardiopatches hold promise for in situ regeneration of infarcted hearts. Here, we describe a novel cardiopatch based on bone morphogenetic protein 2-primed cardiac-committed mouse embryonic stem cells, embedded into biodegradable fibrin matrices and engrafted onto infarcted rat hearts. For in vivo tracking of the engrafted cardiac-committed cells, superparamagnetic iron oxide nanoparticles were magnetofected into the cells, thus enabling detection and functional evaluation by high-resolution magnetic resonance imaging. Six weeks after transplantation into infarcted rat hearts, both local (p < .04) and global (p < .015) heart function, as well as the left ventricular dilation (p < .0011), were significantly improved (p < .001) as compared with hearts receiving cardiopatches loaded with iron nanoparticles alone. Histological analysis revealed that the fibrin scaffolds had degraded over time and clusters of myocyte enhancer factor 2-positive cardiac-committed cells had colonized most of the infarcted myocardium, including the fibrotic area. De novo CD31-positive blood vessels were formed in the vicinity of the transplanted cardiopatch. Altogether, our data provide evidence that stem cell-based cardiopatches represent a promising therapeutic strategy to achieve efficient cell implantation and improved global and regional cardiac function after myocardial infarction. PMID:23197784

Rationale and Design of a Clinical Trial to Evaluate the Safety and Efficacy of Intracoronary Infusion of Allogeneic Human Cardiac Stem Cells in Patients With Acute Myocardial Infarction and Left Ventricular Dysfunction: The Randomized Multicenter Double-Blind Controlled CAREMI Trial (Cardiac Stem Cells in Patients With Acute Myocardial Infarction).

PubMed

Sanz-Ruiz, Ricardo; Casado Plasencia, Ana; Borlado, Luis R; Fernández-Santos, María Eugenia; Al-Daccak, Reem; Claus, Piet; Palacios, Itziar; Sádaba, Rafael; Charron, Dominique; Bogaert, Jan; Mulet, Miguel; Yotti, Raquel; Gilaberte, Immaculada; Bernad, Antonio; Bermejo, Javier; Janssens, Stefan; Fernández-Avilés, Franciso

2017-06-23

Stem cell therapy has increased the therapeutic armamentarium in the fight against ischemic heart disease and heart failure. The administration of exogenous stem cells has been investigated in patients suffering an acute myocardial infarction, with the final aim of salvaging jeopardized myocardium and preventing left ventricular adverse remodeling and functional deterioration. However, phase I and II clinical trials with autologous and first-generation stem cells have yielded inconsistent benefits and mixed results. In the search for new and more efficient cellular regenerative products, interesting cardioprotective, immunoregulatory, and cardioregenerative properties have been demonstrated for human cardiac stem cells. On the other hand, allogeneic cells show several advantages over autologous sources: they can be produced in large quantities, easily administered off-the-shelf early after an acute myocardial infarction, comply with stringent criteria for product homogeneity, potency, and quality control, and may exhibit a distinctive immunologic behavior. With a promising preclinical background, CAREMI (Cardiac Stem Cells in Patients With Acute Myocardial Infarction) has been designed as a double-blind, 2:1 randomized, controlled, and multicenter clinical trial that will evaluate the safety, feasibility, and efficacy of intracoronary delivery of allogeneic human cardiac stem cell in 55 patients with large acute myocardial infarction, left ventricular dysfunction, and at high risk of developing heart failure. This phase I/II clinical trial represents a novel experience in humans with allogeneic cardiac stem cell in a rigorously imaging-based selected group of acute myocardial infarction patients, with detailed safety immunologic assessments and magnetic resonance imaging-based efficacy end points. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02439398. © 2017 American Heart Association, Inc.

Use of genome editing tools in human stem cell-based disease modeling and precision medicine.

PubMed

Wei, Yu-da; Li, Shuang; Liu, Gai-gai; Zhang, Yong-xian; Ding, Qiu-rong

2015-10-01

Precision medicine emerges as a new approach that takes into account individual variability. The successful conduct of precision medicine requires the use of precise disease models. Human pluripotent stem cells (hPSCs), as well as adult stem cells, can be differentiated into a variety of human somatic cell types that can be used for research and drug screening. The development of genome editing technology over the past few years, especially the CRISPR/Cas system, has made it feasible to precisely and efficiently edit the genetic background. Therefore, disease modeling by using a combination of human stem cells and genome editing technology has offered a new platform to generate " personalized " disease models, which allow the study of the contribution of individual genetic variabilities to disease progression and the development of precise treatments. In this review, recent advances in the use of genome editing in human stem cells and the generation of stem cell models for rare diseases and cancers are discussed.

Identification and characterization of cancer stem-like cells from primary carcinoma of the cervix uteri.

PubMed

Feng, Dingqing; Peng, Cheng; Li, Cairong; Zhou, Ying; Li, Min; Ling, Bin; Wei, Haiming; Tian, Zhigang

2009-11-01

Like many other solid tumors, cervical cancer contains a heterogeneous population of cancer cells. Several investigators have identified putative stem cells from solid tumors and cancer cell lines via the capacity to self renew and drive tumor formation. The aim of this study was to identify and characterize a cancer stem-like cell population from primary carcinoma of the cervix uteri. Cervical carcinoma from 19 patients staged I-II following International Federation of Gynecology and Obstetrics (FIGO) criteria were disaggregated and subjected to growth conditions selective for stem cells. Eight of nineteen tumor-derived cultures encompassed stem-like cells capable of self-renewal, extensive proliferation as clonal non-adherent spherical clusters. Cell markers of spheroid were identified as CD44+CK17+. Cell survival assays showed the sphere-forming cells were only 48% inhibited by doxorubicin whereas 78% inhibited by paclitaxel. Chemo-resistance may partly attribute to the exclusive expression of ABC transporter. To investigate the tumorigenicity of these stem-like cells, xenoengraftment of 10(5) dissociated spheroid cells allowed full recapitulation of the original tumor, whereas the same amount of tumor cells without non-adherent spheroid selection remained non-tumorigenic. Stemness properties of these spheroid cells were further established by reverse transcription-PCR and Western blotting, demonstrating the expression of embryonic and adult stemness-related genes (Oct-4, Piwil2, C-myc, Stat3 and Sox2). Based on these findings, we assert that cervical cancer contain a subpopulation of tumor initiating cells with stem-like properties, thus facilitating the approach to therapeutic strategies aimed at eradicating the tumorigenic subpopulation within cervical cancer.

The stem cell secretome and its role in brain repair

PubMed Central

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

2014-01-01

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

Growth factors, stem cells and bronchopulmonary dysplasia.

PubMed

Alphonse, Rajesh S; Thébaud, Bernard

2011-01-01

Bronchopulmonary dysplasia (BPD) is the chronic lung disease of prematurity mainly affecting preterm infants that are born at 24-28 weeks of gestation. Surfactant therapy, antenatal steroids and incremental improvements in perinatal care have modified the pattern of injury and allowed survival of ever more immature infants, but there is still no specific treatment for BPD. As a consequence, this disorder remains the most common complication of extreme prematurity. Arrested alveolar growth and disrupted vasculogenesis, the histological hallmarks of BPD, may persist beyond childhood and lead to chronic lung diseases in adults. Recent advances in our understanding of stem cells and their potential to repair damaged organs offer the possibility for cell-based treatment for intractable diseases. This review summarizes basic concepts of stem cell biology and discusses the recent advances and challenges of stem cell-based therapies for lung diseases, with a particular focus on BPD. Copyright © 2011 S. Karger AG, Basel.

Modeling the Chagas’ disease after stem cell transplantation

NASA Astrophysics Data System (ADS)

Galvão, Viviane; Miranda, José Garcia Vivas

2009-04-01

A recent model for Chagas’ disease after stem cell transplantation is extended for a three-dimensional multi-agent-based model. The computational model includes six different types of autonomous agents: inflammatory cell, fibrosis, cardiomyocyte, proinflammatory cytokine tumor necrosis factor- α, Trypanosoma cruzi, and bone marrow stem cell. Only fibrosis is fixed and the other types of agents can move randomly through the empty spaces using the three-dimensional Moore neighborhood. Bone marrow stem cells can promote apoptosis in inflammatory cells, fibrosis regression and can differentiate in cardiomyocyte. T. cruzi can increase the number of inflammatory cells. Inflammatory cells and tumor necrosis factor- α can increase the quantity of fibrosis. Our results were compared with experimental data giving a fairly fit and they suggest that the inflammatory cells are important for the development of fibrosis.

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

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

Reprogramming Methods Do Not Affect Gene Expression Profile of Human Induced Pluripotent Stem Cells.

PubMed

Trevisan, Marta; Desole, Giovanna; Costanzi, Giulia; Lavezzo, Enrico; Palù, Giorgio; Barzon, Luisa

2017-01-20

Induced pluripotent stem cells (iPSCs) are pluripotent cells derived from adult somatic cells. After the pioneering work by Yamanaka, who first generated iPSCs by retroviral transduction of four reprogramming factors, several alternative methods to obtain iPSCs have been developed in order to increase the yield and safety of the process. However, the question remains open on whether the different reprogramming methods can influence the pluripotency features of the derived lines. In this study, three different strategies, based on retroviral vectors, episomal vectors, and Sendai virus vectors, were applied to derive iPSCs from human fibroblasts. The reprogramming efficiency of the methods based on episomal and Sendai virus vectors was higher than that of the retroviral vector-based approach. All human iPSC clones derived with the different methods showed the typical features of pluripotent stem cells, including the expression of alkaline phosphatase and stemness maker genes, and could give rise to the three germ layer derivatives upon embryoid bodies assay. Microarray analysis confirmed the presence of typical stem cell gene expression profiles in all iPSC clones and did not identify any significant difference among reprogramming methods. In conclusion, the use of different reprogramming methods is equivalent and does not affect gene expression profile of the derived human iPSCs.

Scientists' perspectives on the ethical issues of stem cell research.

PubMed

Longstaff, Holly; Schuppli, Catherine A; Preto, Nina; Lafrenière, Darquise; McDonald, Michael

2009-06-01

This paper describes findings from an ethics education project funded by the Canadian Stem Cell Network (SCN). The project is part of a larger research initiative entitled "The Stem Cell Research Environment: Drawing the Evidence and Experience Together". The ethics education study began with a series of focus groups with SCN researchers and trainees as part of a "needs assessment" effort. The purpose of these discussions was to identify the main ethical issues associated with stem cell (SC) research from the perspective of the stem cell community. This paper will focus on five prominent themes that emerged from the focus group data including: (1) the source of stem cells; (2) the power of stem cells; (3) working within a charged research environment; (4) the regulatory context; and (5) ethics training for scientists. Additional discussions are planned with others involved in Canadian stem cell research (e.g., research ethics board members, policy makers) to supplement initial findings. These assessment results combined with existing bioethics literature will ultimately inform a web-based ethics education module for the SCN. We believe that our efforts are important for those analyzing the ethical, legal, and social issues (ELSI) in this area because our in depth understanding of stem cell researcher perspectives will enable us to develop more relevant and effective education material, which in turn should help SC researchers address the important ethical challenges in their area.

Breast Cancer Stem Cell Therapeutics, Multiple Strategies Versus Using Engineered Mesenchymal Stem Cells With Notch Inhibitory Properties: Possibilities and Perspectives.

PubMed

Bose, Bipasha; Sen, Utsav; Shenoy P, Sudheer

2018-01-01

Relapse cases of cancers are more vigorous and difficult to control due to the preponderance of cancer stem cells (CSCs). Such CSCs that had been otherwise dormant during the first incidence of cancer gradually appear as radiochemoresistant cancer cells. Hence, cancer therapeutics aimed at CSCs would be an effective strategy for mitigating the cancers during relapse. Alternatively, CSC therapy can also be proposed as an adjuvant therapy, along-with the conventional therapies. As regenerative stem cells (RSCs) are known for their trophic effects, anti-tumorogenicity, and better migration toward an injury site, this review aims to address the use of adult stem cells such as dental pulp derived; cord blood derived pure populations of regenerative stem cells for targeting CSCs. Indeed, pro-tumorogenicity of RSCs is of concern and hence has also been dealt with in relation to breast CSC therapeutics. Furthermore, as notch signaling pathways are upregulated in breast cancers, and anti-notch antibody based and sh-RNA based therapies are already in the market, this review focuses the possibilities of engineering RSCs to express notch inhibitory proteins for breast CSC therapeutics. Also, we have drawn a comparison among various possibilities of breast CSC therapeutics, about, notch1 inhibition. J. Cell. Biochem. 119: 141-149, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Mitochondrial functionality in reproduction: from gonads and gametes to embryos and embryonic stem cells.

PubMed

Ramalho-Santos, João; Varum, Sandra; Amaral, Sandra; Mota, Paula C; Sousa, Ana Paula; Amaral, Alexandra

2009-01-01

Mitochondria are multitasking organelles involved in ATP synthesis, reactive oxygen species (ROS) production, calcium signalling and apoptosis; and mitochondrial defects are known to cause physiological dysfunction, including infertility. The goal of this review was to identify and discuss common themes in mitochondrial function related to mammalian reproduction. The scientific literature was searched for studies reporting on the several aspects of mitochondrial activity in mammalian testis, sperm, oocytes, early embryos and embryonic stem cells. ATP synthesis and ROS production are the most discussed aspects of mitochondrial function. Metabolic shifts from mitochondria-produced ATP to glycolysis occur at several stages, notably during gametogenesis and early embryo development, either reflecting developmental switches or substrate availability. The exact role of sperm mitochondria is especially controversial. Mitochondria-generated ROS function in signalling but are mostly described when produced under pathological conditions. Mitochondria-based calcium signalling is primarily important in embryo activation and embryonic stem cell differentiation. Besides pathologically triggered apoptosis, mitochondria participate in apoptotic events related to the regulation of spermatogonial cell number, as well as gamete, embryo and embryonic stem cell quality. Interestingly, data from knock-out (KO) mice is not always straightforward in terms of expected phenotypes. Finally, recent data suggests that mitochondrial activity can modulate embryonic stem cell pluripotency as well as differentiation into distinct cellular fates. Mitochondria-based events regulate different aspects of reproductive function, but these are not uniform throughout the several systems reviewed. Low mitochondrial activity seems a feature of 'stemness', being described in spermatogonia, early embryo, inner cell mass cells and embryonic stem cells.

Endothelial-derived interleukin-6 induces cancer stem cell motility by generating a chemotactic gradient towards blood vessels.

PubMed

Kim, Hong Sun; Chen, Yu-Chih; Nör, Felipe; Warner, Kristy A; Andrews, April; Wagner, Vivian P; Zhang, Zhaocheng; Zhang, Zhixiong; Martins, Manoela D; Pearson, Alexander T; Yoon, Euisik; Nör, Jacques E

2017-11-21

Recent evidence suggests that the metastatic spread of head and neck squamous cell carcinomas (HNSCC) requires the function of cancer stem cells endowed with multipotency, self-renewal, and high tumorigenic potential. We demonstrated that cancer stem cells reside in perivascular niches and are characterized by high aldehyde dehydrogenase (ALDH) activity and high CD44 expression (ALDH high CD44 high ) in HNSCC. Here, we hypothesize that endothelial cell-secreted interleukin-6 (IL-6) contributes to tumor progression by enhancing the migratory phenotype and survival of cancer stem cells. Analysis of tissue microarrays generated from the invasive fronts of 77 HNSCC patients followed-up for up to 11 years revealed that high expression of IL-6 receptor (IL-6R) (p=0.0217) or co-receptor gp130 (p=0.0422) correlates with low HNSCC patient survival. We observed that endothelial cell-secreted factors induce epithelial to mesenchymal transition (EMT) and enhance invasive capacity of HNSCC cancer stem cells. Conditioned medium from CRISPR/Cas9-mediated IL-6 knockout primary human endothelial cells is less chemotactic for cancer stem cells in a microfluidics-based system than medium from control endothelial cells (p<0.05). Blockade of the IL-6 pathway with a humanized anti-IL-6R antibody (tocilizumab) inhibited endothelial cell-induced motility in vitro and decreased the fraction of cancer stem cells in vivo . Notably, xenograft HNSCC tumors vascularized with IL-6-knockout endothelial cells exhibited slower tumor growth and smaller cancer stem cell fraction. These findings demonstrate that endothelial cell-secreted IL-6 enhances the motility and survival of highly tumorigenic cancer stem cells, suggesting that endothelial cells can create a chemotactic gradient that enables the movement of carcinoma cells towards blood vessels.

The expression of cancer stem cell markers in human colorectal carcinoma cells in a microenvironment dependent manner.

PubMed

Stankevicius, Vaidotas; Kunigenas, Linas; Stankunas, Edvinas; Kuodyte, Karolina; Strainiene, Egle; Cicenas, Jonas; Samalavicius, Narimantas E; Suziedelis, Kestutis

2017-03-18

Numerous lines of evidence support the hierarchical model of cancer development and tumor initiation. According to the theory, cancer stem cells play a crucial role in the formation of the tumor and should be targeted for more effective anticancer treatment. However, cancer stem cells quickly loose their characteristics when propagated as 2D cell culture, indicating that the 2D cell culture does not provide the appropriate settings to maintain an in vivo environment. In this study we have investigated the expression of self-renewal, cancer stem cell and epithelial to mesenchymal transition markers after the transfer of human colorectal carcinoma cell DLD1 and HT29 lines from 2D cell cultures to scaffold-attached laminin rich extracellular matrix and scaffold-free multicellular spheroid 3D culture models. Based on the up-regulated expression of multipotency, CSC and EMT markers, our data suggests that human colorectal carcinoma cells grown in 3D exhibit enhanced cancer stem cell characteristics. Therefore, in order to design more efficient targeted therapies, we suggest that 3D cell culture models should be employed in cancer stem cell research. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Stem Cells in Spinal Fusion

PubMed Central

Haudenschild, Dominik R.; Wegner, Adam M.; Klineberg, Eric O.

2017-01-01

Study Design: Review of literature. Objectives: This review of literature investigates the application of mesenchymal stem cells (MSCs) in spinal fusion, highlights potential uses in the development of bone grafts, and discusses limitations based on both preclinical and clinical models. Methods: A review of literature was conducted looking at current studies using stem cells for augmentation of spinal fusion in both animal and human models. Results: Eleven preclinical studies were found that used various animal models. Average fusion rates across studies were 59.8% for autograft and 73.7% for stem cell–based grafts. Outcomes included manual palpation and stressing of the fusion, radiography, micro–computed tomography (μCT), and histological analysis. Fifteen clinical studies, 7 prospective and 8 retrospective, were found. Fusion rates ranged from 60% to 100%, averaging 87.1% in experimental groups and 87.2% in autograft control groups. Conclusions: It appears that there is minimal clinical difference between commercially available stem cells and bone marrow aspirates indicating that MSCs may be a good choice in a patient with poor marrow quality. Overcoming morbidity and limitations of autograft for spinal fusion, remains a significant problem for spinal surgeons and further studies are needed to determine the efficacy of stem cells in augmenting spinal fusion. PMID:29238646

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

PubMed

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

2018-02-08

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

Space-time dynamics of Stem Cell Niches: a unified approach for Plants.

PubMed

Pérez, Maria Del Carmen; López, Alejandro; Padilla, Pablo

2013-06-01

Many complex systems cannot be analyzed using traditional mathematical tools, due to their irreducible nature. This makes it necessary to develop models that can be implemented computationally to simulate their evolution. Examples of these models are cellular automata, evolutionary algorithms, complex networks, agent-based models, symbolic dynamics and dynamical systems techniques. We review some representative approaches to model the stem cell niche in Arabidopsis thaliana and the basic biological mechanisms that underlie its formation and maintenance. We propose a mathematical model based on cellular automata for describing the space-time dynamics of the stem cell niche in the root. By making minimal assumptions on the cell communication process documented in experiments, we classify the basic developmental features of the stem-cell niche, including the basic structural architecture, and suggest that they could be understood as the result of generic mechanisms given by short and long range signals. This could be a first step in understanding why different stem cell niches share similar topologies, not only in plants. Also the fact that this organization is a robust consequence of the way information is being processed by the cells and to some extent independent of the detailed features of the signaling mechanism.

Space-time dynamics of stem cell niches: a unified approach for plants.

PubMed

Pérez, Maria del Carmen; López, Alejandro; Padilla, Pablo

2013-04-02

Many complex systems cannot be analyzed using traditional mathematical tools, due to their irreducible nature. This makes it necessary to develop models that can be implemented computationally to simulate their evolution. Examples of these models are cellular automata, evolutionary algorithms, complex networks, agent-based models, symbolic dynamics and dynamical systems techniques. We review some representative approaches to model the stem cell niche in Arabidopsis thaliana and the basic biological mechanisms that underlie its formation and maintenance. We propose a mathematical model based on cellular automata for describing the space-time dynamics of the stem cell niche in the root. By making minimal assumptions on the cell communication process documented in experiments, we classify the basic developmental features of the stem-cell niche, including the basic structural architecture, and suggest that they could be understood as the result of generic mechanisms given by short and long range signals. This could be a first step in understanding why different stem cell niches share similar topologies, not only in plants. Also the fact that this organization is a robust consequence of the way information is being processed by the cells and to some extent independent of the detailed features of the signaling mechanism.

Plasticity within stem cell hierarchies in mammalian epithelia.

PubMed

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

2015-02-01

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

In vitro differentiation of mouse embryonic stem (mES) cells using the hanging drop method.

PubMed

Wang, Xiang; Yang, Phillip

2008-07-23

Stem cells have the remarkable potential to develop into many different cell types. When a stem cell divides, each new cell has the potential to either remain a stem cell or become another type of cell with a more specialized function, This promising of science is leading scientists to investigate the possibility of cell-based therapies to treat disease. When culture in suspension without antidifferentiation factors, embryonic stem cells spontaneously differentiate and form three-dimensional multicellular aggregates. These cell aggregates are called embryoid bodies(EB). Hanging drop culture is a widely used EB formation induction method. The rounded bottom of hanging drop allows the aggregation of ES cells which can provide mES cells a good environment for forming EBs. The number of ES cells aggregatied in a hanging drop can be controlled by varying the number of cells in the initial cell suspension to be hung as a drop from the lid of Petri dish. Using this method we can reproducibly form homogeneous EBs from a predetermined number of ES cells.

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.

Stem cell transplantation for treating Parkinson's disease: Literature analysis based on the Web of Science.

PubMed

Li, Runhui

2012-06-05

To identify global research trends of stem cell transplantation for treating Parkinson's disease using a bibliometric analysis of the Web of Science. We performed a bibliometric analysis of data retrievals for stem cell transplantation for treating Parkinson's disease from 2002 to 2011 using the Web of Science. (a) peer-reviewed articles on stem cell transplantation for treating Parkinson's disease which were published and indexed in the Web of Science; (b) type of articles: original research articles, reviews, meeting abstracts, proceedings papers, book chapters, editorial material and news items; (c) year of publication: 2002-2011. (a) articles that required manual searching or telephone access; (b) we excluded documents that were not published in the public domain; (c) we excluded a number of corrected papers from the total number of articles. (1) Type of literature; (2) annual publication output; (3) distribution according to journals; (4) distribution according to subject areas; (5) distribution according to country; (6) distribution according to institution; (7) comparison of countries that published the most papers on stem cell transplantation from different cell sources for treating Parkinson's disease; (8) comparison of institutions that published the most papers on stem cell transplantation from different cell sources for treating Parkinson's disease in the Web of Science from 2002 to 2011; (9) comparison of studies on stem cell transplantation from different cell sources for treating Parkinson's disease. In total, 1 062 studies on stem cell transplantation for treating Parkinson's disease appeared in the Web of Science from 2002 to 2011, almost one third of which were from American authors and institutes. The number of studies on stem cell transplantation for treating Parkinson's disease had gradually increased over the past 10 years. Papers on stem cell transplantation for treating Parkinson's disease appeared in journals such as Stem Cells and Experimental Neurology. Although the United States published more articles addressing neural stem cell and embryonic stem cell transplantation for treating Parkinson's disease, China ranked first for articles published on bone marrow mesenchymal stem cell transplantation for treating Parkinson's disease. From our analysis of the literature and research trends, we found that stem cell transplantation for treating Parkinson's disease may offer further benefits in regenerative medicine.

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.

Expansion of donor-derived hematopoietic stem cells with PIGA mutation associated with late graft failure after allogeneic stem cell transplantation.

PubMed

Mochizuki, Kanako; Sugimori, Chiharu; Qi, Zhirong; Lu, Xuzhang; Takami, Akiyoshi; Ishiyama, Ken; Kondo, Yukio; Yamazaki, Hirohito; Okumura, Hirokazu; Nakao, Shinji

2008-09-01

A small population of CD55(-)CD59(-) blood cells was detected in a patient who developed donor-type late graft failure after allogeneic stem cell transplantation (SCT) for treatment of aplastic anemia (AA). Chimerism and PIGA gene analyses showed the paroxysmal nocturnal hemoglobinuria (PNH)-type granulocytes to be of a donor-derived stem cell with a thymine insertion in PIGA exon 2. A sensitive mutation-specific polymerase chain reaction (PCR)-based analysis detected the mutation exclusively in DNA derived from the donor bone marrow (BM) cells. The patient responded to immunosuppressive therapy and achieved transfusion independence. The small population of PNH-type cells was undetectable in any of the 50 SCT recipients showing stable engraftment. The de novo development of donor cell-derived AA with a small population of PNH-type cells in this patient supports the concept that glycosyl phosphatidylinositol-anchored protein-deficient stem cells have a survival advantage in the setting of immune-mediated BM injury.

MtDNA depleted PC3 cells exhibit Warburg effect and cancer stem cell features

PubMed Central

Li, Xiaoran; Zhong, Yali; Lu, Jie; Axcrona, Karol; Eide, Lars; Syljuåsen, Randi G.; Peng, Qian; Wang, Junbai; Zhang, Hongquan; Goscinski, Mariusz Adam; Kvalheim, Gunnar; Nesland, Jahn M.; Suo, Zhenhe

2016-01-01

Reducing mtDNA content was considered as a critical step in the metabolism restructuring for cell stemness restoration and further neoplastic development. However, the connections between mtDNA depletion and metabolism reprograming-based cancer cell stemness in prostate cancers are still lack of studies. Here, we demonstrated that human CRPC cell line PC3 tolerated high concentration of the mtDNA replication inhibitor ethidium bromide (EtBr) and the mtDNA depletion triggered a universal metabolic remodeling process. Failure in completing that process caused lethal consequences. The mtDNA depleted (MtDP) PC3 cells could be steadily maintained in the special medium in slow cycling status. The MtDP PC3 cells contained immature mitochondria and exhibited Warburg effect. Furthermore, the MtDP PC3 cells were resistant to therapeutic treatments and contained greater cancer stem cell-like subpopulations: CD44+, ABCG2+, side-population and ALDHbright. In conclusion, these results highlight the association of mtDNA content, mitochondrial function and cancer cell stemness features. PMID:27248169

Aberrant epithelial GREM1 expression initiates colonic tumorigenesis from cells outside of the crypt base stem cell niche

PubMed Central

Bansal, Mukesh; Rafferty, Hannah; Boitsova, Tatjana; Bardella, Chiara; Jaeger, Emma; Lewis, Annabelle; Freeman-Mills, Luke; Giner, Francesc Castro; Rodenas-Cuadrado, Pedro; Mallappa, Sreelakshmi; Clark, Susan; Thomas, Huw; Jeffery, Rosemary; Poulsom, Richard; Rodriguez-Justo, Manuel; Novelli, Marco; Chetty, Runjan; Silver, Andrew; Sansom, Owen James; Greten, Florian R; Wang, Lai Mun; East, James Edward; Tomlinson, Ian; Leedham, Simon John

2015-01-01

Hereditary mixed polyposis syndrome (HMPS) is characterised by the development of mixed morphology colorectal tumours and is caused by a 40 kb duplication that results in aberrant epithelial expression of the mesenchymal Bone Morphogenetic Protein antagonist, GREM1. Here we use HMPS tissue and a mouse model of the disease to show that epithelial GREM1 disrupts homeostatic intestinal morphogen gradients, altering cell-fate, that is normally determined by position along the vertical epithelial axis. This promotes the persistence and/or reacquisition of stem-cell properties in Lgr5 negative (non-expressing) progenitor cells that have exited the stem-cell niche. These cells form ectopic crypts, proliferate, accumulate somatic mutations and can initiate intestinal neoplasia, indicating that the crypt base stem-cell is not the sole cell-of-origin of colorectal cancer. Furthermore, we show that epithelial expression of GREM1 also occurs in traditional serrated adenomas, sporadic pre-malignant lesions with a hitherto unknown pathogenesis and these lesions can be considered the sporadic equivalents of HMPS polyps. PMID:25419707

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.

Development of an encapsulated stem cell-based therapy for diabetes.

PubMed

Tomei, Alice Anna; Villa, Chiara; Ricordi, Camillo

2015-01-01

Islet transplantation can treat the most severe cases of type 1 diabetes but it currently requires deceased donor pancreata as an islet source and chronic immunosuppression to prevent rejection and recurrence of autoimmunity. Stem cell-derived insulin-producing cells may address the shortage of organ donors, whereas cell encapsulation may reduce or eliminate the requirement for immunosuppression, minimizing the risks associated with the islet transplantation procedure, and potentially prolonging graft survival. This review focuses on the design principles for immunoisolation devices and on stem cell differentiation into insulin-producing cell products. The reader will gain understanding of the different types of immunoisolation devices and the key parameters that affect the outcome of the encapsulated graft. Progresses in stem cell differentiation towards mature endocrine islet cells, including the most recent clinical trials and the challenges associated with the application of immunoisolation devices designed for primary islets to stem-cell products, are also discussed. Recent advancements in the field of stem cell-derived islet cell products and immunoisolation strategies hold great promise for type 1 diabetes. However, a combination product including both cells and an immunoisolation strategy still needs to be optimized and tested for safety and efficacy.

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 Cell Therapies for Knee Cartilage Repair: The Current Status of Preclinical and Clinical Studies

PubMed Central

Anderson, John A.; Little, Dianne; Toth, Alison P.; Moorman, Claude T.; Tucker, Bradford S.; Ciccotti, Michael G.; Guilak, Farshid

2014-01-01

Background Articular cartilage damage of the knee is common, causing significant morbidity worldwide. Many adult tissues contain cells that are able to differentiate into multiple cell types, including chondrocytes. These stem cells have gained significant attention over the past decade and may become frontline management for cartilage defects in the very near future. Purpose The role of stem cells in the treatment of knee osteochondral defects was reviewed. Recent animal and clinical studies were reviewed to determine the benefits and potential outcomes of using stem cells for cartilage defects. Study Design Literature review. Methods A PubMed search was undertaken. The key phrase “stem cells and knee” was used. The search included reviews and original articles over an unlimited time period. From this search, articles outlining animal and clinical trials were selected. A search of current clinical trials in progress was performed on the clinicaltrials.gov website, and “stem cells and knee” was used as the search phrase. Results Stem cells have been used in many recent in vitro and animal studies. A number of cell-based approaches for cartilage repair have progressed from preclinical animal studies into clinical trials. Conclusion The use of stem cells for the treatment of cartilage defects is increasing in animal and clinical studies. Methods of delivery of stem cells to the knee’s cartilage vary from direct injection to implantation with scaffolds. While these approaches are highly promising, there is currently limited evidence of a direct clinical benefit, and further research is required to assess the overall outcome of stem cell therapies for knee cartilage repair. PMID:24220016

Adipose-Derived Stem Cells in Functional Bone Tissue Engineering: Lessons from Bone Mechanobiology

PubMed Central

Bodle, Josephine C.; Hanson, Ariel D.

2011-01-01

This review aims to highlight the current and significant work in the use of adipose-derived stem cells (ASC) in functional bone tissue engineering framed through the bone mechanobiology perspective. Over a century of work on the principles of bone mechanosensitivity is now being applied to our understanding of bone development. We are just beginning to harness that potential using stem cells in bone tissue engineering. ASC are the primary focus of this review due to their abundance and relative ease of accessibility for autologous procedures. This article outlines the current knowledge base in bone mechanobiology to investigate how the knowledge from this area has been applied to the various stem cell-based approaches to engineering bone tissue constructs. Specific emphasis is placed on the use of human ASC for this application. PMID:21338267

Identification of epithelial label-retaining cells at the transition between the anal canal and the rectum in mice

PubMed Central

Runck, Laura A; Kramer, Megan; Ciraolo, Georgianne; Lewis, Alfor G

2010-01-01

In certain regions of the body, transition zones exist where stratified squamous epithelia directly abut against other types of epithelia. Certain transition zones are especially prone to tumorigenesis an example being the anorectal junction, although the reason for this is not known. One possibility is that the abrupt transition of the simple columnar epithelium of the colon to the stratified squamous epithelium of the proximal portion of the anal canal may contain a unique stem cell niche. We investigated whether the anorectal region contained cells with stem cell properties relative to the adjacent epithelium. We utilized a tetracycline-regulatable histone H2B-GFP transgenic mice model, previously used to identify hair follicle stem cells, to fluorescently label slow-cycling anal epithelial cells (e.g., prospective stem cells) in combination with a panel of putative stem cell markers. We identified a population of long-term GFP label-retaining cells concentrated at the junction between the anal canal and the rectum. These cells are BrdU-retaining cells and expressed the stem cell marker CD34. Moreover, tracking the fate of the anal label-retaining cells in vivo revealed that the slow-cycling cells only gave rise to progeny of the anal epithelium. In conclusion, we identified a unique population of cells at the anorectal junction which can be separated from the other basal anal epithelial cells based upon the expression of the stem cell marker CD34 and integrin α6, and thus represent a putative anal stem cell population. PMID:20647777

Storage related changes of cell wall based dietary fiber components of broccoli (Brassica oleracea var. italica) stems.

PubMed

Schäfer, Judith; Stanojlovic, Luisa; Trierweiler, Bernhard; Bunzel, Mirko

2017-03-01

Storage related changes in the cell wall composition potentially affect the texture of plant-based foods and the physiological effects of cell wall based dietary fiber components. Therefore, a detailed characterization of cell wall polysaccharides and lignins from broccoli stems was performed. Freshly harvested broccoli and broccoli stored at 20°C and 1°C for different periods of time were analyzed. Effects on dietary fiber contents, polysaccharide composition, and on lignin contents/composition were much more pronounced during storage at 20°C than at 1°C. During storage, insoluble dietary fiber contents of broccoli stems increased up to 13%. Storage related polysaccharide modifications include an increase of the portions of cellulose, xylans, and homogalacturonans and a decrease of the neutral pectic side-chains arabinans and galactans. Broccoli stem lignins are generally rich in guaiacyl units. Lignins from freshly harvested broccoli stems contain slightly larger amounts of p-hydroxyphenyl units than syringyl units. Syringyl units are predominantly incorporated into the lignin polymers during storage, resulting in increased acetyl bromide soluble lignin contents. NMR-based analysis of the interunit linkage types of broccoli stem lignins revealed comparably large portions of resinol structures for a guaiacyl rich lignin. Incorporation of syringyl units into the polymers over storage predominantly occurs through β-O-4-linkages. Copyright © 2017 Elsevier Ltd. All rights reserved.

Selection based on CD133 and high aldehyde dehydrogenase activity isolates long-term reconstituting human hematopoietic stem cells

PubMed Central

Hess, David A.; Wirthlin, Louisa; Craft, Timothy P.; Herrbrich, Phillip E.; Hohm, Sarah A.; Lahey, Ryan; Eades, William C.; Creer, Michael H.; Nolta, Jan A.

2006-01-01

The development of novel cell-based therapies requires understanding of distinct human hematopoietic stem and progenitor cell populations. We recently isolated reconstituting hematopoietic stem cells (HSCs) by lineage depletion and purification based on high aldehyde dehydrogenase activity (ALDHhiLin- cells). Here, we further dissected the ALDHhi-Lin- population by selection for CD133, a surface molecule expressed on progenitors from hematopoietic, endothelial, and neural lineages. ALDHhiCD133+Lin- cells were primarily CD34+, but also included CD34-CD38-CD133+ cells, a phenotype previously associated with repopulating function. Both ALDHhiCD133-Lin- and ALDHhiCD133+Lin- cells demonstrated distinct clonogenic progenitor function in vitro, whereas only the ALDHhiCD133+Lin- population seeded the murine bone marrow 48 hours after transplantation. Significant human cell repopulation was observed only in NOD/SCID and NOD/SCID β2M-null mice that received transplants of ALDHhiCD133+Lin- cells. Limiting dilution analysis demonstrated a 10-fold increase in the frequency of NOD/SCID repopulating cells compared with CD133+Lin- cells, suggesting that high ALDH activity further purified cells with repopulating function. Transplanted ALDHhiCD133+Lin- cells also maintained primitive hematopoietic phenotypes (CD34+CD38-) and demonstrated enhanced repopulating function in recipients of serial, secondary transplants. Cell selection based on ALDH activity and CD133 expression provides a novel purification of HSCs with long-term repopulating function and may be considered an alternative to CD34 cell selection for stem cell therapies. PMID:16269619

Stem cells in sepsis and acute lung injury.

PubMed

Cribbs, Sushma K; Matthay, Michael A; Martin, Greg S

2010-12-01

Sepsis and acute lung injury continue to be major causes of morbidity and mortality worldwide despite advances in our understanding of pathophysiology and the discovery of new management strategies. Recent investigations show that stem cells may be beneficial as prognostic biomarkers and novel therapeutic strategies in these syndromes. This article reviews the potential use of endogenous adult tissue-derived stem cells in sepsis and acute lung injury as prognostic markers and also as exogenous cell-based therapy. A directed systematic search of the medical literature using PubMed and OVID, with particular emphasis on the time period after 2002, was done to evaluate topics related to 1) the epidemiology and pathophysiology of sepsis and acute lung injury; and 2) the definition, characterization, and potential use of stem cells in these diseases. DATA SYNTHESIS AND FINDINGS: When available, preferential consideration was given to prospective nonrandomized clinical and preclinical studies. Stem cells have shown significant promise in the field of critical care both for 1) prognostic value and 2) treatment strategies. Although several recent studies have identified the potential benefit of stem cells in sepsis and acute lung injury, further investigations are needed to more completely understand stem cells and their potential prognostic and therapeutic value.

Droplet Microarray Based on Patterned Superhydrophobic Surfaces Prevents Stem Cell Differentiation and Enables High-Throughput Stem Cell Screening.

PubMed

Tronser, Tina; Popova, Anna A; Jaggy, Mona; Bastmeyer, Martin; Levkin, Pavel A

2017-12-01

Over the past decades, stem cells have attracted growing interest in fundamental biological and biomedical research as well as in regenerative medicine, due to their unique ability to self-renew and differentiate into various cell types. Long-term maintenance of the self-renewal ability and inhibition of spontaneous differentiation, however, still remain challenging and are not fully understood. Uncontrolled spontaneous differentiation of stem cells makes high-throughput screening of stem cells also difficult. This further hinders investigation of the underlying mechanisms of stem cell differentiation and the factors that might affect it. In this work, a dual functionality of nanoporous superhydrophobic-hydrophilic micropatterns is demonstrated in their ability to inhibit differentiation of mouse embryonic stem cells (mESCs) and at the same time enable formation of arrays of microdroplets (droplet microarray) via the effect of discontinuous dewetting. Such combination makes high-throughput screening of undifferentiated mouse embryonic stem cells possible. The droplet microarray is used to investigate the development, differentiation, and maintenance of stemness of mESC, revealing the dependence of stem cell behavior on droplet volume in nano- and microliter scale. The inhibition of spontaneous differentiation of mESCs cultured on the droplet microarray for up to 72 h is observed. In addition, up to fourfold increased cell growth rate of mESCs cultured on our platform has been observed. The difference in the behavior of mESCs is attributed to the porosity and roughness of the polymer surface. This work demonstrates that the droplet microarray possesses the potential for the screening of mESCs under conditions of prolonged inhibition of stem cells' spontaneous differentiation. Such a platform can be useful for applications in the field of stem cell research, pharmacological testing of drug efficacy and toxicity, biomedical research as well as in the field of regenerative medicine and tissue engineering. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Induced Pluripotent Stem Cell Models to Enable In Vitro Models for Screening in the Central Nervous System.

PubMed

Hunsberger, Joshua G; Efthymiou, Anastasia G; Malik, Nasir; Behl, Mamta; Mead, Ivy L; Zeng, Xianmin; Simeonov, Anton; Rao, Mahendra

2015-08-15

There is great need to develop more predictive drug discovery tools to identify new therapies to treat diseases of the central nervous system (CNS). Current nonpluripotent stem cell-based models often utilize non-CNS immortalized cell lines and do not enable the development of personalized models of disease. In this review, we discuss why in vitro models are necessary for translational research and outline the unique advantages of induced pluripotent stem cell (iPSC)-based models over those of current systems. We suggest that iPSC-based models can be patient specific and isogenic lines can be differentiated into many neural cell types for detailed comparisons. iPSC-derived cells can be combined to form small organoids, or large panels of lines can be developed that enable new forms of analysis. iPSC and embryonic stem cell-derived cells can be readily engineered to develop reporters for lineage studies or mechanism of action experiments further extending the utility of iPSC-based systems. We conclude by describing novel technologies that include strategies for the development of diversity panels, novel genomic engineering tools, new three-dimensional organoid systems, and modified high-content screens that may bring toxicology into the 21st century. The strategic integration of these technologies with the advantages of iPSC-derived cell technology, we believe, will be a paradigm shift for toxicology and drug discovery efforts.

Establishment and Characterization of a Tumor Stem Cell-Based Glioblastoma Invasion Model.

PubMed

Jensen, Stine Skov; Meyer, Morten; Petterson, Stine Asferg; Halle, Bo; Rosager, Ann Mari; Aaberg-Jessen, Charlotte; Thomassen, Mads; Burton, Mark; Kruse, Torben A; Kristensen, Bjarne Winther

2016-01-01

Glioblastoma is the most frequent and malignant brain tumor. Recurrence is inevitable and most likely connected to tumor invasion and presence of therapy resistant stem-like tumor cells. The aim was therefore to establish and characterize a three-dimensional in vivo-like in vitro model taking invasion and tumor stemness into account. Glioblastoma stem cell-like containing spheroid (GSS) cultures derived from three different patients were established and characterized. The spheroids were implanted in vitro into rat brain slice cultures grown in stem cell medium and in vivo into brains of immuno-compromised mice. Invasion was followed in the slice cultures by confocal time-lapse microscopy. Using immunohistochemistry, we compared tumor cell invasion as well as expression of proliferation and stem cell markers between the models. We observed a pronounced invasion into brain slice cultures both by confocal time-lapse microscopy and immunohistochemistry. This invasion closely resembled the invasion in vivo. The Ki-67 proliferation indexes in spheroids implanted into brain slices were lower than in free-floating spheroids. The expression of stem cell markers varied between free-floating spheroids, spheroids implanted into brain slices and tumors in vivo. The established invasion model kept in stem cell medium closely mimics tumor cell invasion into the brain in vivo preserving also to some extent the expression of stem cell markers. The model is feasible and robust and we suggest the model as an in vivo-like model with a great potential in glioma studies and drug discovery.

Characterization of human pancreatic progenitor cells.

PubMed

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

2010-01-01

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

Evidence for circulating cancer stem-like cells and epithelial-mesenchymal transition phenotype in the pleurospheres derived from lung adenocarcinoma using liquid biopsy.

PubMed

Mirza, Sheefa; Jain, Nayan; Rawal, Rakesh

2017-03-01

Lung cancer stem cells are supposed to be the main drivers of tumor initiation, maintenance, drug resistance, and relapse of the disease. Hence, identification of the cellular and molecular aspects of these cells is a prerequisite for targeted therapy of lung cancer. Currently, analysis of circulating tumor cells has the potential to become the main diagnostic technique to monitor disease progression or therapeutic response as it is non-invasive. However, accurate detection of circulating tumor cells has remained a challenge, as epithelial cell markers used so far are not always trustworthy for detecting circulating tumor cells, especially during epithelial-mesenchymal transition. As cancer stem cells are the only culprit to initiate metastatic tumors, our aim was to isolate and characterize circulating tumor stem cells rather than circulating tumor cells from the peripheral blood of NSCLC adenocarcinoma as limited data are available addressing the gene expression profiling of lung cancer stem cells. Here, we reveal that CD44(+)/CD24(-) population in circulation not only exhibit stem cell-related genes but also possess epithelial-mesenchymal transition characteristics. In conclusion, the use of one or more cancer stem cell markers along with epithelial, mesenchymal and epithelial mesenchymal transition markers will prospectively provide the most precise assessment of the threat for recurrence and metastatic disease and has a great potential for forthcoming applications in harvesting circulating tumor stem cells and their downstream applications. Our results will aid in developing diagnostic and prognostic modalities and personalized treatment regimens like dendritic cell-based immunotherapy that can be utilized for targeting and eliminating circulating tumor stem cells, to significantly reduce the possibility of relapse and improve clinical outcomes.

Near-field photothermal microspectroscopy for adult stem-cell identification and characterization.

PubMed

Grude, Olaug; Hammiche, Azzedine; Pollock, Hubert; Bentley, Adam J; Walsh, Michael J; Martin, Francis L; Fullwood, Nigel J

2007-12-01

The identification of stem cells in adult tissue is a challenging problem in biomedicine. Currently, stem cells are identified by individual epitopes, which are generally tissue specific. The discovery of a stem-cell marker common to other adult tissue types could open avenues in the development of therapeutic stem-cell strategies. We report the use of the novel technique of Fourier transform infrared near-field photothermal microspectroscopy (FTIR-PTMS) for the characterization of stem cells, transit amplifying (TA) cells and terminally differentiated (TD) cells in the corneal epithelium. Principal component analysis (PCA) data demonstrate excellent discrimination of cell type by spectra. PCA in combination with linear discriminant analysis (PCA-LDA) shows that FTIR-PTMS very effectively discriminates between the three cell populations. Statistically significant differences above the 99% confidence level between IR spectra from stem cells and TA cells suggest that nucleic acid conformational changes are an important component of the differences between spectral data from the two cell types. FTIR-PTMS is a new addition to existing spectroscopy methods based on the concept of interfacing a conventional FTIR spectrometer with an atomic force microscope equipped with a near-field thermal sensing probe. FTIR-PTMS spectroscopy currently has spatial resolution that is similar to that of diffraction-limited optical detection FTIR spectroscopy techniques, but as a near-field probing technique has considerable potential for further improvement. Our work also suggests that FTIR-PTMS is potentially more sensitive than synchrotron radiation FTIR spectroscopy for some applications. Microspectroscopy techniques like FTIR-PTMS provide information about the entire molecular composition of cells, in contrast to epitope recognition that only considers the presence or absence of individual molecules. Our results with FTIR-PTMS on corneal stem cells are promising for the potential development of an IR spectral fingerprint for stem cells.

Establishment of stem cell lines from nuclear transferred and parthenogenetically activated mouse oocytes for therapeutic cloning.

PubMed

Ju, Jin Young; Park, Chun Young; Gupta, Mukesh Kumar; Uhm, Sang Jun; Paik, Eun Chan; Ryoo, Zae Young; Cho, Youl Hee; Chung, Kil Saeng; Lee, Hoon Taek

2008-05-01

To establish embryonic stem cell lines from nuclear transfer of somatic cell nuclei isolated from the same oocyte donor and from parthenogenetic activation. The study also evaluated the effect of the micromanipulation procedure on the outcome of somatic cell nuclear transfer in mice. Randomized, prospective study. Hospital-based assisted reproductive technology laboratory. F(1) (C57BL/6 x 129P3/J) mice. Metaphase II-stage oocytes were either parthenogenetically activated or nuclear transferred with cumulus cell nuclei or parthenogenetically activated after a sham-manipulation procedure. Embryogenesis and embryonic stem cell establishment. The development rate to morula/blastocyst of nuclear transferred oocytes (27.9% +/- 5.9%) was significantly lower than that of the sham-manipulated (84.1% +/- 5.6%) or parthenogenetic (98.6% +/- 1.4%) groups. A sharp decrease in cleavage potential was obvious in the two- to four-cell transition for the nuclear transferred embryos (79.0% +/- 4.6% and 43.3% +/- 5.0%), implying incomplete nuclear reprogramming in arrested oocytes. However, the cleavage, as well as the development rate, of parthenogenetic and sham-manipulated groups did not differ significantly. The embryonic stem cell line establishment rate was higher from parthenogenetically activated oocytes (15.7%) than nuclear transferred (4.3%) or sham-manipulated oocytes (12.5%). Cell colonies from all groups displayed typical morphology of mice embryonic stem cells and could be maintained successfully with undifferentiated morphology after continuous proliferation for more than 120 passages still maintaining normal karyotype. All these cells were positive for mice embryonic stem cell markers such as Oct-4 and SSEA-1 based on immunocytochemistry and reverse transcriptase-polymerase chain reaction. The clonal origin of the ntES cell line and the parthenogenetic embryonic stem cell lines were confirmed by polymerase chain reaction analysis of the polymorphic markers. Blastocyst injection experiments demonstrated that these lines contributed to resulting chimeras and are germ-line competent. We report the establishment of ntES cell lines from somatic cells isolated from same individual. Our data also suggest that embryo micromanipulation procedure during the nuclear transfer procedure influences the developmental ability and embryonic stem cell establishment rate of nuclear transferred embryos.

Ancestral trees for modeling stem cell lineages genetically rather than functionally: understanding mutation accumulation and distinguishing the restrictive cancer stem cell propagation theory and the unrestricted cell propagation theory of human tumorigenesis.

PubMed

Shibata, Darryl K; Kern, Scott E

2008-01-01

Cancer stem cells either could be rare or common in tumors, constituting the major distinction between the two fundamentally opposed theoretical models of tumor progression: A newer and restrictive stem cell propagation model, in which the stem cells are a small and special minority of the tumor cells, and a standard older model, an unrestricted cell proliferation theory, in which many or most tumor cells are capable of indefinite generations of cell division. Stem cells of tumors are difficult to quantitate using functional assays, and the validity of the most common assays is seriously questioned. Nonetheless, stem cells are an essential component of any tumorigenesis model. Alternative approaches to studying tumor stem cells should be explored. Cell populations can be conceived of as having a genealogy, a relationship of cells to their ancestral lineage, from the zygote to the adult cells or neoplasms. Models using ancestral trees thus offer an anatomic and genetic means to "observe" stem cells independent of artificial conditions. Ancestral trees broaden our attention backward along a lineage, to the zygote stage, and thereby add insight into how the mutations of tumors accumulate. It is possible that a large fraction of mutations in a tumor originate from normal, endogenous, replication errors (nearly all being passenger mutations) occurring prior to the emergence of the first transformed cell. Trees can be constructed from experimental measurements - molecular clocks - of real human tissues and tumors. Detailed analysis of single-cell methylation patterns, heritable yet slightly plastic, now can provide this information in the necessary depth. Trees based on observations of molecular clocks may help us to distinguish between competing theories regarding the proliferative properties among cells of actual human tumors, to observe subtle and difficult phenomena such as the extinction of stem lineages, and to address the origins and rates of mutations in various normal, hormone-stimulated, aging, or neoplastic tissues. The simple concept that cancers arise from the transformation of a normal stem cell, the stem cell origination theory, is sometimes superficially and confusingly referred to as "the stem cell theory". This concept is compatible with but not a requisite assumption for both of the major competing theories of tumor progression, and plays essentially no role in clarifying the nature of tumor progression.

Generation of functional hepatocyte-like cells from human deciduous periodontal ligament stem cells.

PubMed

Vasanthan, Punitha; Jayaraman, Pukana; Kunasekaran, Wijenthiran; Lawrence, Anthony; Gnanasegaran, Nareshwaran; Govindasamy, Vijayendran; Musa, Sabri; Kasim, Noor Hayaty Abu

2016-08-01

Human deciduous periodontal ligament stem cells have been introduced for as an easily accessible source of stem cells from dental origin. Although recent studies have revealed the ability of these stem cells in multipotential attribute, their efficiency of hepatic lineage differentiation has not been addressed so far. The aim of this study is to investigate hepatic lineage fate competence of periodontal ligament stem cells through direct media induction. Differentiation of periodontal ligament stem cells into hepatocyte-like cells was conducted by the exposure of two phase media induction. First phase was performed in the presence of hepatocyte growth factors to induce a definitive endoderm formation. In the subsequent phase, the cells were treated with oncostatin M and dexamethosone followed by insulin and transferrin to generate hepatocyte-like cells. Hepatic-related characters of the generated hepatocyte-like cells were determined at both mRNA and protein level followed by functional assays. Foremost changes observed in the generation of hepatocyte-like cells were the morphological features in which these cells were transformed from fibroblastic shape to polygonal shape. Temporal expression of hepatic markers ranging from early endodermal up to late markers were detected in the hepatocyte-like cells. Crucial hepatic markers such as glycogen storage, albumin, and urea secretion were also shown. These findings exhibited the ability of periodontal ligament stem cells of dental origin to be directed into hepatic lineage fate. These cells can be regarded as an alternative autologous source in the usage of stem cell-based treatment for liver diseases.

Generation of functional hepatocyte-like cells from human deciduous periodontal ligament stem cells

NASA Astrophysics Data System (ADS)

Vasanthan, Punitha; Jayaraman, Pukana; Kunasekaran, Wijenthiran; Lawrence, Anthony; Gnanasegaran, Nareshwaran; Govindasamy, Vijayendran; Musa, Sabri; Kasim, Noor Hayaty Abu

2016-08-01

Human deciduous periodontal ligament stem cells have been introduced for as an easily accessible source of stem cells from dental origin. Although recent studies have revealed the ability of these stem cells in multipotential attribute, their efficiency of hepatic lineage differentiation has not been addressed so far. The aim of this study is to investigate hepatic lineage fate competence of periodontal ligament stem cells through direct media induction. Differentiation of periodontal ligament stem cells into hepatocyte-like cells was conducted by the exposure of two phase media induction. First phase was performed in the presence of hepatocyte growth factors to induce a definitive endoderm formation. In the subsequent phase, the cells were treated with oncostatin M and dexamethosone followed by insulin and transferrin to generate hepatocyte-like cells. Hepatic-related characters of the generated hepatocyte-like cells were determined at both mRNA and protein level followed by functional assays. Foremost changes observed in the generation of hepatocyte-like cells were the morphological features in which these cells were transformed from fibroblastic shape to polygonal shape. Temporal expression of hepatic markers ranging from early endodermal up to late markers were detected in the hepatocyte-like cells. Crucial hepatic markers such as glycogen storage, albumin, and urea secretion were also shown. These findings exhibited the ability of periodontal ligament stem cells of dental origin to be directed into hepatic lineage fate. These cells can be regarded as an alternative autologous source in the usage of stem cell-based treatment for liver diseases.

Development of new stem cell-based technologies for carnivore reproduction research.

PubMed

Travis, A J; Kim, Y; Meyers-Wallen, V

2009-07-01

New reproductive technologies based on stem cells offer several potential benefits to carnivore species. For example, development of lines of embryonic stem cells in cats and dogs would allow for the generation of transgenic animal models, which could be used to advance both veterinary and human health. Techniques such as spermatogonial stem cell transplantation (SSCT) and testis xenografting offer new approaches to propagate genetically valuable individual males, even if they should die before producing sperm. These techniques might therefore have application to the conservation of endangered species of carnivores, as well as to biomedical research. Recently, our laboratory has successfully performed SSCT in the dog, with a recipient dog producing sperm of donor genetic origin. Testis xenografting has been used to produce sperm from pre-pubertal testis tissue from both cats and ferrets. These early steps reinforce the need not only for research on stem cell technologies, but also for additional research into complementary technologies of assisted reproduction in carnivores, so that the widest array of research and clinical benefits can be realized.

The use of stem cells in aesthetic dermatology and plastic surgery procedures. A compact review of experimental and clinical applications

PubMed Central

Nowacki, Maciej; Kloskowski, Tomasz; Pietkun, Katarzyna; Zegarski, Maciej; Pokrywczyńska, Marta; Habib, Samy L.; Drewa, Tomasz

2017-01-01

The aim of this paper was to collect currently available data related to the use of stem cells in aesthetic dermatology and plastic surgery based on a systemic review of experimental and clinical applications. We found that the use of stem cells is very promising but the current state of art is still not effective. This situation is connected with not fully known mechanisms of cell interactions, possible risks and side effects. We think that there is a big need to create and conduct different studies which could resolve problems of stem cells use for implementation into aesthetic dermatology and plastic surgery. PMID:29422816

The use of stem cells in aesthetic dermatology and plastic surgery procedures. A compact review of experimental and clinical applications.

PubMed

Nowacki, Maciej; Kloskowski, Tomasz; Pietkun, Katarzyna; Zegarski, Maciej; Pokrywczyńska, Marta; Habib, Samy L; Drewa, Tomasz; Zegarska, Barbara

2017-12-01

The aim of this paper was to collect currently available data related to the use of stem cells in aesthetic dermatology and plastic surgery based on a systemic review of experimental and clinical applications. We found that the use of stem cells is very promising but the current state of art is still not effective. This situation is connected with not fully known mechanisms of cell interactions, possible risks and side effects. We think that there is a big need to create and conduct different studies which could resolve problems of stem cells use for implementation into aesthetic dermatology and plastic surgery.

Functional genomic characterization of neoblast-like stem cells in larval Schistosoma mansoni

PubMed Central

Wang, Bo; Collins, James J; Newmark, Phillip A

2013-01-01

Schistosomes infect hundreds of millions of people in the developing world. Transmission of these parasites relies on a stem cell-driven, clonal expansion of larvae inside a molluscan intermediate host. How this novel asexual reproductive strategy relates to current models of stem cell maintenance and germline specification is unclear. Here, we demonstrate that this proliferative larval cell population (germinal cells) shares some molecular signatures with stem cells from diverse organisms, in particular neoblasts of planarians (free-living relatives of schistosomes). We identify two distinct germinal cell lineages that differ in their proliferation kinetics and expression of a nanos ortholog. We show that a vasa/PL10 homolog is required for proliferation and maintenance of both populations, whereas argonaute2 and a fibroblast growth factor receptor-encoding gene are required only for nanos-negative cells. Our results suggest that an ancient stem cell-based developmental program may have enabled the evolution of the complex life cycle of parasitic flatworms. DOI: http://dx.doi.org/10.7554/eLife.00768.001 PMID:23908765

Functional Human Podocytes Generated in Organoids from Amniotic Fluid Stem Cells

PubMed Central

Benedetti, Valentina; Novelli, Rubina; Abbate, Mauro; Rizzo, Paola; Conti, Sara; Tomasoni, Susanna; Corna, Daniela; Pozzobon, Michela; Cavallotti, Daniela; Yokoo, Takashi; Morigi, Marina; Benigni, Ariela; Remuzzi, Giuseppe

2016-01-01

Generating kidney organoids using human stem cells could offer promising prospects for research and therapeutic purposes. However, no cell-based strategy has generated nephrons displaying an intact three-dimensional epithelial filtering barrier. Here, we generated organoids using murine embryonic kidney cells, and documented that these tissues recapitulated the complex three-dimensional filtering structure of glomerular slits in vivo and accomplished selective glomerular filtration and tubular reabsorption. Exploiting this technology, we mixed human amniotic fluid stem cells with mouse embryonic kidney cells to establish three-dimensional chimeric organoids that engrafted in vivo and grew to form vascularized glomeruli and tubular structures. Human cells contributed to the formation of glomerular structures, differentiated into podocytes with slit diaphragms, and internalized exogenously infused BSA, thus attaining in vivo degrees of specialization and function unprecedented for donor stem cells. In conclusion, human amniotic fluid stem cell chimeric organoids may offer new paths for studying renal development and human podocyte disease, and for facilitating drug discovery and translational research. PMID:26516208

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.

Stem cells therapy for ALS.

PubMed

Mazzini, Letizia; Vescovi, Angelo; Cantello, Roberto; Gelati, Maurizio; Vercelli, Alessandro

2016-01-01

Despite knowledge on the molecular basis of amyotrophic lateral sclerosis (ALS) having quickly progressed over the last few years, such discoveries have not yet translated into new therapeutics. With the advancement of stem cell technologies there is hope for stem cell therapeutics as novel treatments for ALS. We discuss in detail the therapeutic potential of different types of stem cells in preclinical and clinical works. Moreover, we address many open questions in clinical translation. SC therapy is a potentially promising new treatment for ALS and the need to better understand how to develop cell-based experimental treatments, and how to implement them in clinical trials, becomes more pressing. Mesenchymal stem cells and neural fetal stem cells have emerged as safe and potentially effective cell types, but there is a need to carry out appropriately designed experimental studies to verify their long-term safety and possibly efficacy. Moreover, the cost-benefit analysis of the results must take into account the quality of life of the patients as a major end point. It is our opinion that a multicenter international clinical program aime d at fine-tuning and coordinating transplantation procedures and protocols is mandatory.

Engineered stem cell mimics to enhance stroke recovery.

PubMed

George, Paul M; Oh, Byeongtaek; Dewi, Ruby; Hua, Thuy; Cai, Lei; Levinson, Alexa; Liang, Xibin; Krajina, Brad A; Bliss, Tonya M; Heilshorn, Sarah C; Steinberg, Gary K

2018-06-13

Currently, no medical therapies exist to augment stroke recovery. Stem cells are an intriguing treatment option being evaluated, but cell-based therapies have several challenges including developing a stable cell product with long term reproducibility. Since much of the improvement observed from cellular therapeutics is believed to result from trophic factors the stem cells release over time, biomaterials are well-positioned to deliver these important molecules in a similar fashion. Here we show that essential trophic factors secreted from stem cells can be effectively released from a multi-component hydrogel system into the post-stroke environment. Using our polymeric system to deliver VEGF-A and MMP-9, we improved recovery after stroke to an equivalent degree as observed with traditional stem cell treatment in a rodent model. While VEGF-A and MMP-9 have many unique mechanisms of action, connective tissue growth factor (CTGF) interacts with both VEGF-A and MMP-9. With our hydrogel system as well as with stem cell delivery, the CTGF pathway is shown to be downregulated with improved stroke recovery. Copyright © 2018 Elsevier Ltd. All rights reserved.

Hematopoietic stem cell transplantation in thalassemia major and sickle cell disease: indications and management recommendations from an international expert panel

PubMed Central

Angelucci, Emanuele; Matthes-Martin, Susanne; Baronciani, Donatella; Bernaudin, Françoise; Bonanomi, Sonia; Cappellini, Maria Domenica; Dalle, Jean-Hugues; Di Bartolomeo, Paolo; de Heredia, Cristina Díaz; Dickerhoff, Roswitha; Giardini, Claudio; Gluckman, Eliane; Hussein, Ayad Achmed; Kamani, Naynesh; Minkov, Milen; Locatelli, Franco; Rocha, Vanderson; Sedlacek, Petr; Smiers, Frans; Thuret, Isabelle; Yaniv, Isaac; Cavazzana, Marina; Peters, Christina

2014-01-01

Thalassemia major and sickle cell disease are the two most widely disseminated hereditary hemoglobinopathies in the world. The outlook for affected individuals has improved in recent years due to advances in medical management in the prevention and treatment of complications. However, hematopoietic stem cell transplantation is still the only available curative option. The use of hematopoietic stem cell transplantation has been increasing, and outcomes today have substantially improved compared with the past three decades. Current experience world-wide is that more than 90% of patients now survive hematopoietic stem cell transplantation and disease-free survival is around 80%. However, only a few controlled trials have been reported, and decisions on patient selection for hematopoietic stem cell transplantation and transplant management remain principally dependent on data from retrospective analyses and on the clinical experience of the transplant centers. This consensus document from the European Blood and Marrow Transplantation Inborn Error Working Party and the Paediatric Diseases Working Party aims to report new data and provide consensus-based recommendations on indications for hematopoietic stem cell transplantation and transplant management. PMID:24790059

Roles of autophagy in controlling stem cell identity: a perspective of self-renewal and differentiation.

PubMed

Sotthibundhu, Areechun; Promjuntuek, Wilasinee; Liu, Min; Shen, Sanbing; Noisa, Parinya

2018-04-25

Autophagy is crucial for the removal of dysfunctional organelles and protein aggregates and for maintaining stem cell homeostasis, which includes self-renewal, cell differentiation and somatic reprogramming. Loss of self-renewal capacity and pluripotency is a major obstacle to stem cell-based therapies. It has been reported that autophagy regulates stem cells under biological stimuli, starvation, hypoxia, generation of reactive oxygen species (ROS) and cellular senescence. On the one hand, autophagy is shown to play roles in self-renewal by co-function with the ubiquitin-proteasome system (UPS) to promote pluripotency-associated proteins (NANOG, OCT4 and SOX2) in human embryonic stem cells (hESCs). On the other hand, autophagy activity acts as cell reprogramming processes that play an important role for clearance fate determination and upregulates neural and cardiac differentiation. Deregulation of autophagy triggers protein disorders such as neurodegenerative cardiac/muscle diseases and cancer. Therefore, understanding of the roles of the autophagy in stem cell renewal and differentiation may benefit therapeutic development for a range of human diseases.

Automatic cell cloning assay for determining the clonogenic capacity of cancer and cancer stem-like cells.

PubMed

Fedr, Radek; Pernicová, Zuzana; Slabáková, Eva; Straková, Nicol; Bouchal, Jan; Grepl, Michal; Kozubík, Alois; Souček, Karel

2013-05-01

The clonogenic assay is a well-established in vitro method for testing the survival and proliferative capability of cells. It can be used to determine the cytotoxic effects of various treatments including chemotherapeutics and ionizing radiation. However, this approach can also characterize cells with different phenotypes and biological properties, such as stem cells or cancer stem cells. In this study, we implemented a faster and more precise method for assessing the cloning efficiency of cancer stem-like cells that were characterized and separated using a high-speed cell sorter. Cell plating onto a microplate using an automatic cell deposition unit was performed in a single-cell or dilution rank mode by the fluorescence-activated cell sorting method. We tested the new automatic cell-cloning assay (ACCA) on selected cancer cell lines and compared it with the manual approach. The obtained results were also compared with the results of the limiting dilution assay for different cell lines. We applied the ACCA to analyze the cloning capacity of different subpopulations of prostate and colon cancer cells based on the expression of the characteristic markers of stem (CD44 and CD133) and cancer stem cells (TROP-2, CD49f, and CD44). Our results revealed that the novel ACCA is a straightforward approach for determining the clonogenic capacity of cancer stem-like cells identified in both cell lines and patient samples. Copyright © 2013 International Society for Advancement of Cytometry.

Circulating Tumor Cells: From Theory to Nanotechnology-Based Detection.

PubMed

Ming, Yue; Li, Yuanyuan; Xing, Haiyan; Luo, Minghe; Li, Ziwei; Chen, Jianhong; Mo, Jingxin; Shi, Sanjun

2017-01-01

Cancer stem cells with stem-cell properties are regarded as tumor initiating cells. Sharing stem-cell properties, circulating tumor cells (CTCs) are responsible for the development of metastasis, which significant affects CTC analysis in clinical practice. Due to their extremely low occurrence in blood, however, it is challenging to enumerate and analyze CTCs. Nanotechnology is able to address the problems of insufficient capture efficiency and low purity of CTCs owing to the unique structural and functional properties of nanomaterials, showing strong promise for CTC isolation and detection. In this review, we discuss the role of stem-like CTCs in metastases, provide insight into recent progress in CTC isolation and detection approaches using various nanoplatforms, and highlight the role of nanotechnology in the advancement of CTC research.

Vectors to Increase Production Efficiency of Inducible Pluripotent Stem Cell (iPSC) | NCI Technology Transfer Center | TTC

Cancer.gov

This invention describes the discovery that specific p53 isoform increase the number of inducible pluripotent stem cells (iPS). It is known that the activity of p53 regulates the self-renewal and pluripotency of normal and cancer stem cells, and also affects re-programming efficiency of iPS cells. This p53 isoform-based technology provides a more natural process of increasing iPS cell production than previous methods of decreasing p53. NCI seeks licensees for this technology.

Superior Red Blood Cell Generation from Human Pluripotent Stem Cells Through a Novel Microcarrier-Based Embryoid Body Platform.

PubMed

Sivalingam, Jaichandran; Lam, Alan Tin-Lun; Chen, Hong Yu; Yang, Bin Xia; Chen, Allen Kuan-Liang; Reuveny, Shaul; Loh, Yuin-Han; Oh, Steve Kah-Weng

2016-08-01

In vitro generation of red blood cells (RBCs) from human embryonic stem cells and human induced pluripotent stem cells appears to be a promising alternate approach to circumvent shortages in donor-derived blood supplies for clinical applications. Conventional methods for hematopoietic differentiation of human pluripotent stem cells (hPSC) rely on embryoid body (EB) formation and/or coculture with xenogeneic cell lines. However, most current methods for hPSC expansion and EB formation are not amenable for scale-up to levels required for large-scale RBC generation. Moreover, differentiation methods that rely on xenogenic cell lines would face obstacles for future clinical translation. In this study, we report the development of a serum-free and chemically defined microcarrier-based suspension culture platform for scalable hPSC expansion and EB formation. Improved survival and better quality EBs generated with the microcarrier-based method resulted in significantly improved mesoderm induction and, when combined with hematopoietic differentiation, resulted in at least a 6-fold improvement in hematopoietic precursor expansion, potentially culminating in a 80-fold improvement in the yield of RBC generation compared to a conventional EB-based differentiation method. In addition, we report efficient terminal maturation and generation of mature enucleated RBCs using a coculture system that comprised primary human mesenchymal stromal cells. The microcarrier-based platform could prove to be an appealing strategy for future scale-up of hPSC culture, EB generation, and large-scale generation of RBCs under defined and xeno-free conditions.

Generation of H1 PAX6WT/EGFP reporter cells to purify PAX6 positive neural stem/progenitor cells.

PubMed

Wu, Wei; Liu, Juli; Su, Zhenghui; Li, Zhonghao; Ma, Ning; Huang, Ke; Zhou, Tiancheng; Wang, Linli

2018-08-25

Neural conversion from human pluripotent cells (hPSCs) is a potential therapy to neurological disease in the future. However, this is still limited by efficiency and stability of existed protocols used for neural induction from hPSCs. To overcome this obstacle, we developed a reporter system to screen PAX6 + neural progenitor/stem cells using transcription activator like effector nuclease (TALEN). We found that knock-in 2 A-EGFP cassette into PAX6 exon of human embryonic stem cells H1 with TALEN-based homology recombination could establish PAX6 WT/EGFP H1 reporter cell line fast and efficiently. This reporter cell line could differentiate into PAX6 and EGFP double positive neural progenitor/stem cells (NPCs/NSCs) after neural induction. Those PAX6 WT/EGFP NPCs could be purified, expanded and specified to post-mitotic neurons in vitro efficiently. With this reporter cell line, we also screened out 1 NPC-specific microRNA, hsa-miR-99a-5p, and 3 ESCs-enriched miRNAs, hsa-miR-302c-5p, hsa-miR-512-3p and hsa-miR-518 b. In conclusion, the TALEN-based neural stem cell screening system is safe and efficient and could help researcher to acquire adequate and pure neural progenitor cells for further application. Copyright © 2018 Elsevier Inc. All rights reserved.

MicroRNA-Mediated Down-Regulation of Apoptosis Signal-Regulating Kinase 1 (ASK1) Attenuates the Apoptosis of Human Mesenchymal Stem Cells (MSCs) Transplanted into Infarcted Heart.

PubMed

Lee, Chang Youn; Shin, Sunhye; Lee, Jiyun; Seo, Hyang-Hee; Lim, Kyu Hee; Kim, Hyemin; Choi, Jung-Won; Kim, Sang Woo; Lee, Seahyung; Lim, Soyeon; Hwang, Ki-Chul

2016-10-20

Stem cell therapy using adult stem cells, such as mesenchymal stem cells (MSCs) has produced some promising results in treating the damaged heart. However, the low survival rate of MSCs after transplantation is still one of the crucial factors that limit the therapeutic effect of stem cells. In the damaged heart, oxidative stress due to reactive oxygen species (ROS) production can cause the death of transplanted MSCs. Apoptosis signal-regulating kinase 1 (ASK1) has been implicated in the development of oxidative stress-related pathologic conditions. Thus, we hypothesized that down-regulation of ASK1 in human MSCs (hMSCs) might attenuate the post-transplantation death of MSCs. To test this hypothesis, we screened microRNAs (miRNAs) based on a miRNA-target prediction database and empirical data and investigated the anti-apoptotic effect of selected miRNAs on human adipose-derived stem cells (hASCs) and on rat myocardial infarction (MI) models. Our data indicated that miRNA-301a most significantly suppressed ASK1 expression in hASCs. Apoptosis-related genes were significantly down-regulated in miRNA-301a-enriched hASCs exposed to hypoxic conditions. Taken together, these data show that miRNA-mediated down-regulation of ASK1 protects MSCs during post-transplantation, leading to an increase in the efficacy of MSC-based cell therapy.

In vitro expansion impaired the stemness of early passage mesenchymal stem cells for treatment of cartilage defects

PubMed Central

Jiang, Tongmeng; Xu, Guojie; Wang, Qiuyan; Yang, Lihui; Zheng, Li; Zhao, Jinmin; Zhang, Xingdong

2017-01-01

In vitro cultured autologous mesenchymal stem cells (MSCs) within passage 5 have been approved for clinical application in stem cell-based treatment of cartilage defects. However, their chondrogenic potential has not yet been questioned or verified. In this study, the chondrogenic potential of bone marrow MSCs at passage 3 (P3 BMSCs) was investigated both in cartilage repair and in vitro, with freshly isolated bone marrow mononuclear cells (BMMNCs) as controls. The results showed that P3 BMSCs were inferior to BMMNCs not only in their chondrogenic differentiation ability but also as candidates for long-term repair of cartilage defects. Compared with BMMNCs, P3 BMSCs presented a decay in telomerase activity and a change in chromosomal morphology with potential anomalous karyotypes, indicating senescence. In addition, interindividual variability in P3 BMSCs is much higher than in BMMNCs, demonstrating genomic instability. Interestingly, remarkable downregulation in cell cycle, DNA replication and mismatch repair (MMR) pathways as well as in multiple genes associated with telomerase activity and chromosomal stability were found in P3 BMSCs. This result indicates that telomerase and chromosome anomalies might originate from expansion, leading to impaired stemness and pluripotency of stem cells. In vitro culture and expansion are not recommended for cell-based therapy, and fresh BMMNCs are the first choice. PMID:28569773

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

Gelovani, Juri G.

Objectives. The overall objective of this application is to develop novel technologies for non-invasive imaging of adoptive stem cell-based therapies with positron emission tomography (PET) that would be applicable to human patients. To achieve this objective, stem cells will be genetically labeled with a PET-reporter gene and repetitively imaged to assess their distribution, migration, differentiation, and persistence using a radiolabeled reporter probe. This new imaging technology will be tested in adoptive progenitor cell-based therapy models in animals, including: delivery pro-apoptotic genes to tumors, and T-cell reconstitution for immunostimulatory therapy during allogeneic bone marrow progenitor cell transplantation. Technical and Scientific Merits.more » Non-invasive whole body imaging would significantly aid in the development and clinical implementation of various adoptive progenitor cell-based therapies by providing the means for non-invasive monitoring of the fate of injected progenitor cells over a long period of observation. The proposed imaging approaches could help to address several questions related to stem cell migration and homing, their long-term viability, and their subsequent differentiation. The ability to image these processes non-invasively in 3D and repetitively over a long period of time is very important and will help the development and clinical application of various strategies to control and direct stem cell migration and differentiation. Approach to accomplish the work. Stem cells will be genetically with a reporter gene which will allow for repetitive non-invasive “tracking” of the migration and localization of genetically labeled stem cells and their progeny. This is a radically new approach that is being developed for future human applications and should allow for a long term (many years) repetitive imaging of the fate of tissues that develop from the transplanted stem cells. Why the approach is appropriate. The novel approach to stem cell imaging is proposed to circumvent the major limitation of in vitro radiolabeling – the eventual radiolabel decay. Stable transduction of stem cells in vitro would allow for the selection of high quality stem cells with optimal functional parameters of the transduced reporter systems. The use of a long-lived radioisotope 124I to label a highly specific reporter gene probe will allow for ex vivo labeling of stem cells and their imaging immediately after injection and during the following next week. The use of short-lived radioisotopes (i.e., 18F) to label highly specific reporter gene probes will allow repetitive PET imaging for the assessment of to stem cell migration, targeting, differentiation, and long-term viability of stem cell-derived tissues. Qualifications of the research team and resources. An established research team of experts in various disciplines has been assembled at MD Anderson Cancer Center (MDACC) over the past two years including the PI, senior co-investigators and collaborators. The participants of this team are recognized internationally to be among the leaders in their corresponding fields of research and clinical medicine. The resources at MDACC are exceptionally well developed and have been recently reinforced by the installation of a microPET and microSPECT/CT cameras, and a 7T MRI system for high resolution animal imaging; and by integrating a synthetic chemistry core for the development and production of precursors for radiolabeling.« less

ReNeuron Group plc.

PubMed

Sinden, John D

2006-01-01

ReNeuron is a UK-based pioneer in stem cell research and development. The Company has leading edge, proprietary somatic stem cell technologies from which it is developing groundbreaking cell therapy products. ReNeuron's focus is on cell therapy treatments designed to reverse the effects of major diseases such as stroke, diabetes and diseases of the eye.

HIGH INFORMATION CONTENT TOXICITY SCREENING USING MOUSE AND HUMAN STEM CELL MODELS OF ENDOCRINE DEVELOPMENT AND FUNCTION

EPA Science Inventory

The project will result in the rapid assessment of chemicals for adverse effects on the development of gametes, adipocytes, and islet B-cells; and on the adipocyte and B-cell endocrine signaling function in human and murine embryonic stem cells. Based on the data, hierarchical...

Cryopreservation of Human Mesenchymal Stem Cells for Clinical Applications: Current Methods and Challenges.

PubMed

Yong, Kar Wey; Wan Safwani, Wan Kamarul Zaman; Xu, Feng; Wan Abas, Wan Abu Bakar; Choi, Jane Ru; Pingguan-Murphy, Belinda

2015-08-01

Mesenchymal stem cells (MSCs) hold many advantages over embryonic stem cells (ESCs) and other somatic cells in clinical applications. MSCs are multipotent cells with strong immunosuppressive properties. They can be harvested from various locations in the human body (e.g., bone marrow and adipose tissues). Cryopreservation represents an efficient method for the preservation and pooling of MSCs, to obtain the cell counts required for clinical applications, such as cell-based therapies and regenerative medicine. Upon cryopreservation, it is important to preserve MSCs functional properties including immunomodulatory properties and multilineage differentiation ability. Further, a biosafety evaluation of cryopreserved MSCs is essential prior to their clinical applications. However, the existing cryopreservation methods for MSCs are associated with notable limitations, leading to a need for new or improved methods to be established for a more efficient application of cryopreserved MSCs in stem cell-based therapies. We review the important parameters for cryopreservation of MSCs and the existing cryopreservation methods for MSCs. Further, we also discuss the challenges to be addressed in order to preserve MSCs effectively for clinical applications.

Stem cell fusion as an ultimate line of defense against xenobiotics.

PubMed

Padron Velazquez, Julio Lazaro

2006-01-01

There are several indications that the potential of stem cells to fuse with somatic cells is extremely high and, what's more exciting, in some instances goes as far as reprogramming and/or rescuing altered cells. It remains unclear, however, how frequent this mechanism is and what patho-physiological role it might play in nature. A plausible hypothesis, discussed in this paper, suggests that stem cell niches might provide a safeguard for the intact genome and epigenome. By fusing with somatic de-differentiated cells, stem cells might consent epigenetic reprogramming and/or genetic recovery of genes which otherwise could drive altered cells to malignancy. If the many sophisticated mechanisms of metabolism, cell repair, programmed cell death and tissue regeneration should fail, stem cells might represent a final attempt to recover dedifferentiated cells to avoid inflowing in cancer. In the current reappraisal of the different mechanisms of defense against xenobiotics, even the incidence of cancer itself is considered an evolving mechanism which, through a kind of programmed death of individuals exhibiting defective mutations, favors advancement of the phenotypes which adapt best. Additionally, with regard to the mechanisms of transmitting somatic mutations, based on stem cells' capacity to migrate and to fuse, here it is speculated that stem cells might be capable of carrying acquired somatic mutations from peripheral tissues to the gonads, and transmit that information into the germinal line. If appropriately demonstrated, these mechanisms might delineate a novel therapeutic area to be explored. The use of stem cells to reprogram/recover irreversibly damaged cells or to transmit beneficial mutations might be a valuable therapeutic approach in the future.

Unraveling the non-senescence phenomenon in Hydra.

PubMed

Dańko, Maciej J; Kozłowski, Jan; Schaible, Ralf

2015-10-07

Unlike other metazoans, Hydra does not experience the distinctive rise in mortality with age known as senescence, which results from an increasing imbalance between cell damage and cell repair. We propose that the Hydra controls damage accumulation mainly through damage-dependent cell selection and cell sloughing. We examine our hypothesis with a model that combines cellular damage with stem cell renewal, differentiation, and elimination. The Hydra individual can be seen as a large single pool of three types of stem cells with some features of differentiated cells. This large stem cell community prevents "cellular damage drift," which is inevitable in complex conglomerate (differentiated) metazoans with numerous and generally isolated pools of stem cells. The process of cellular damage drift is based on changes in the distribution of damage among cells due to random events, and is thus similar to Muller's ratchet in asexual populations. Events in the model that are sources of randomness include budding, cellular death, and cellular damage and repair. Our results suggest that non-senescence is possible only in simple Hydra-like organisms which have a high proportion and number of stem cells, continuous cell divisions, an effective cell selection mechanism, and stem cells with the ability to undertake some roles of differentiated cells. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Mesenchymal stem cell therapy in cats: Current knowledge and future potential.

PubMed

Quimby, Jessica M; Borjesson, Dori L

2018-03-01

Practical relevance: Stem cell therapy is an innovative field of scientific investigation with tremendous potential for clinical application in veterinary medicine. Based on the known desirable immunomodulatory properties of mesenchymal stem cells, this therapy holds promise for the treatment of a variety of inflammatory diseases in cats. This review details our current understanding of feline stem cell biology and proposed mechanism of action. Studies performed in feline clinical trials for diseases including gingivostomatitis, chronic enteropathy, asthma and kidney disease are summarized, with the goal of providing an overview of the current status of this treatment modality and its potential for the future.

A Web-Based Stem Cell Transplant Support System or Standard Care in Young Patients Undergoing Stem Cell Transplant and Their Families

ClinicalTrials.gov

2011-07-11

Chronic Myeloproliferative Disorders; Leukemia; Lymphoma; Myelodysplastic Syndromes; Myelodysplastic/Myeloproliferative Neoplasms; Neuroblastoma; Ovarian Cancer; Psychosocial Effects of Cancer and Its Treatment; Sarcoma

Cryopreservation Method for the Effective Collection of Dental Pulp Stem Cells.

PubMed

Takebe, Yusuke; Tatehara, Seiko; Fukushima, Tatsuhiro; Tokuyama-Toda, Reiko; Yasuhara, Rika; Mishima, Kenji; Satomura, Kazuhito

2017-05-01

Dental pulp stem cells (DPSCs) are an attractive cell source for use in cell-based therapy, regenerative medicine, and tissue engineering because DPSCs have a high cell proliferation ability and multidifferentiation capacity. However, several problems are associated with the collection and preservation of DPSCs for use in future cell-based therapy. In particular, the isolation of DPSCs for cryopreservation is time consuming and expensive. In this study, we developed a novel cryopreservation method (NCM) for dental pulp tissues to isolate suitable DPSCs after thawing cryopreserved tissue. Using the NCM, dental pulp tissues were cultured on adhesion culture dishes for 5 days and then cryopreserved. After thawing, the cryopreserved dental pulp tissue fragments exhibited cell migration. We evaluated each property of DPSCs isolated using the NCM (DPSCs-NCM) and the explant method alone without cryopreservation (DPSCs-C). DPSCs-NCM had the same proliferation capacity as DPSCs-C. Flow cytometry (FACS) analysis indicated that both DPSCs-NCM and DPSCs-C were positive for mesenchymal stem cell markers at the same level but negative for hematopoietic cell markers. Moreover, both DPSCs-NCM and DPSCs-C could differentiate into osteogenic, chondrogenic, and adipogenic cells during culture in each induction medium. These results suggest that DPSCs-NCM may be mesenchymal stem cells. Therefore, our novel method might facilitate the less expensive cryopreservation of DPSCs, thereby providing suitable DPSCs for use in patients in future cell-based therapies.

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.

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.

Translational findings from cardiovascular stem cell research.

PubMed

Mazhari, Ramesh; Hare, Joshua M

2012-01-01

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

Exploiting pluripotent stem cell technology for drug discovery, screening, safety, and toxicology assessments.

PubMed

McGivern, Jered V; Ebert, Allison D

2014-04-01

In order for the pharmaceutical industry to maintain a constant flow of novel drugs and therapeutics into the clinic, compounds must be thoroughly validated for safety and efficacy in multiple biological and biochemical systems. Pluripotent stem cells, because of their ability to develop into any cell type in the body and recapitulate human disease, may be an important cellular system to add to the drug development repertoire. This review will discuss some of the benefits of using pluripotent stem cells for drug discovery and safety studies as well as some of the recent applications of stem cells in drug screening studies. We will also address some of the hurdles that need to be overcome in order to make stem cell-based approaches an efficient and effective tool in the quest to produce clinically successful drug compounds. Copyright © 2013 Elsevier B.V. All rights reserved.

Optical Spectroscopy for Noninvasive Monitoring of Stem Cell Differentiation

PubMed Central

Downes, Andrew; Mouras, Rabah; Elfick, Alistair

2010-01-01

There is a requirement for a noninvasive technique to monitor stem cell differentiation. Several candidates based on optical spectroscopy are discussed in this review: Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and coherent anti-Stokes Raman scattering (CARS) microscopy. These techniques are briefly described, and the ability of each to distinguish undifferentiated from differentiated cells is discussed. FTIR spectroscopy has demonstrated its ability to distinguish between stem cells and their derivatives. Raman spectroscopy shows a clear reduction in DNA and RNA concentrations during embryonic stem cell differentiation (agreeing with the well-known reduction in the nucleus to cytoplasm ratio) and also shows clear increases in mineral content during differentiation of mesenchymal stem cells. CARS microscopy can map these DNA, RNA, and mineral concentrations at high speed, and Mutliplex CARS spectroscopy/microscopy is highlighted as the technique with most promise for future applications. PMID:20182537

Practical Integration-Free Episomal Methods for Generating Human Induced Pluripotent Stem Cells.

PubMed

Kime, Cody; Rand, Tim A; Ivey, Kathryn N; Srivastava, Deepak; Yamanaka, Shinya; Tomoda, Kiichiro

2015-10-06

The advent of induced pluripotent stem (iPS) cell technology has revolutionized biomedicine and basic research by yielding cells with embryonic stem (ES) cell-like properties. The use of iPS-derived cells for cell-based therapies and modeling of human disease holds great potential. While the initial description of iPS cells involved overexpression of four transcription factors via viral vectors that integrated within genomic DNA, advances in recent years by our group and others have led to safer and higher quality iPS cells with greater efficiency. Here, we describe commonly practiced methods for non-integrating induced pluripotent stem cell generation using nucleofection of episomal reprogramming plasmids. These methods are adapted from recent studies that demonstrate increased hiPS cell reprogramming efficacy with the application of three powerful episomal hiPS cell reprogramming factor vectors and the inclusion of an accessory vector expressing EBNA1. Copyright © 2015 John Wiley & Sons, Inc.

Amniotic-Fluid Stem Cells: Growth Dynamics and Differentiation Potential after a CD-117-Based Selection Procedure

PubMed Central

Arnhold, S.; Glüer, S.; Hartmann, K.; Raabe, O.; Addicks, K.; Wenisch, S.; Hoopmann, M.

2011-01-01

Amniotic fluid (AF) has become an interesting source of fetal stem cells. However, AF contains heterogeneous and multiple, partially differentiated cell types. After isolation from the amniotic fluid, cells were characterized regarding their morphology and growth dynamics. They were sorted by magnetic associated cell sorting using the surface marker CD 117. In order to show stem cell characteristics such as pluripotency and to evaluate a possible therapeutic application of these cells, AF fluid-derived stem cells were differentiated along the adipogenic, osteogenic, and chondrogenic as well as the neuronal lineage under hypoxic conditions. Our findings reveal that magnetic associated cell sorting (MACS) does not markedly influence growth characteristics as demonstrated by the generation doubling time. There was, however, an effect regarding an altered adipogenic, osteogenic, and chondrogenic differentiation capacity in the selected cell fraction. In contrast, in the unselected cell population neuronal differentiation is enhanced. PMID:21437196

5-Azacytidine delivered by mesoporous silica nanoparticles regulates the differentiation of P19 cells into cardiomyocytes

NASA Astrophysics Data System (ADS)

Cheng, Jin; Ding, Qian; Wang, Jia; Deng, Lin; Yang, Lu; Tao, Lei; Lei, Haihong; Lu, Shaoping

2016-01-01

Heart disease is one of the deadliest diseases causing mortality due to the limited regenerative capability of highly differentiated cardiomyocytes. Stem cell-based therapy in tissue engineering is one of the most exciting and rapidly growing areas and raises promising prospects for cardiac repair. In this study, we have synthesized FITC-mesoporous silica nanoparticles (FMSNs) based on a sol-gel method (known as Stöber's method) as a drug delivery platform to transport 5-azacytidine in P19 embryonic carcinoma stem cells. The surfactant CTAB is utilized as a liquid crystal template to self-aggregate into micelles, resulting in the synthesis of MSNs. Based on the cell viability assay, treatment with FMSNs + 5-azacytidine resulted in much more significant inhibition of the proliferation than 5-azacytidine alone. To study the mechanism, we have tested the differentiation genes and cardiac marker genes in P19 cells and found that these genes have been up-regulated in P19 embryonic carcinoma stem cells treated with FMSNs + 5-azacytidine + poly(allylamine hydrochloride) (PAH), with the changes of histone modifications on the regulatory region. In conclusion, with FMSNs as drug delivery platforms, 5-azacytidine can be more efficiently delivered into stem cells and can be used to monitor and track the transfection process in situ to clarify their effects on stem cell functions and the differentiation process, which can serve as a promising tool in tissue engineering and other biomedical fields.

Establishing a Quality Control System for Stem Cell-Based Medicinal Products in China

PubMed Central

2015-01-01

Stem cell-based medicinal products (SCMPs) are emerging as novel therapeutic products. The success of its development depends on the existence of an effective quality control system, which is constituted by quality control technologies, standards, reference materials, guidelines, and the associated management system in accordance with regulatory requirements along product lifespan. However, a worldwide, effective quality control system specific for SCMPs is still far from established partially due to the limited understanding of stem cell sciences and lack of quality control technologies for accurately assessing the safety and biological effectiveness of SCMPs before clinical use. Even though, based on the existing regulations and current stem cell sciences and technologies, initial actions toward the goal of establishing such a system have been taken as exemplified by recent development of new “interim guidelines” for governing quality control along development of SCMPs and new development of the associated quality control technologies in China. In this review, we first briefly introduced the major institutions involved in the regulation of cell substrates and therapeutic cell products in China and the existing regulatory documents and technical guidelines used as critical references for developing the new interim guidelines. With focus only on nonhematopoietic stem cells, we then discussed the principal quality attributes of SCMPs as well as our thinking of proper testing approaches to be established with relevant evaluation technologies to ensure all quality requirements of SCMPs along different manufacturing processes and development stages. At the end, some regulatory and technical challenges were also discussed with the conclusion that combined efforts should be taken to promote stem cell regulatory sciences to establish the effective quality control system for SCMPs. PMID:25471126

Link Protein N-Terminal Peptide as a Potential Stimulating Factor for Stem Cell-Based Cartilage Regeneration

PubMed Central

Xiong, Zekang; Lin, Hui; Zhao, Lei; Li, Zhiliang; Wang, Zhe; Peggrem, Shaun; Xia, Zhidao

2018-01-01

Background Link protein N-terminal peptide (LPP) in extracellular matrix (ECM) of cartilage could induce synthesis of proteoglycans and collagen type II in cartilaginous cells. Cartilage stem/progenitor cells (CSPCs), the endogenous stem cells in cartilage, are important in cartilage degeneration and regeneration. We hypothesized that LPP could be a stimulator for stem cell-based cartilage regeneration by affecting biological behaviors of CSPC. Methods CSPCs were isolated from rat knee cartilage. We evaluated the promoting effect of LPP on proliferation, migration, and chondrogenic differentiation of CSPCs. The chondrogenic differentiation-related genes and proteins were quantitated. Three-dimensional culture of CSPC was conducted in the presence of TGF-β3 or LPP, and the harvested pellets were analyzed to assess the function of LPP on cartilage regeneration. Results LPP stimulated the proliferation of CSPC and accelerated the site-directional migration. Higher expression of SOX9, collagen II, and aggrecan were demonstrated in CSPCs treated with LPP. The pellets treated with LPP showed more distinct characteristics of chondroid differentiation than those with TGF-β3. Conclusion LPP showed application prospect in cartilage regeneration medicine by stimulating proliferation, migration, and chondrogenic differentiation of cartilage stem/progenitor cells. PMID:29531532

Human Pluripotent Stem Cell-Based Assay Predicts Developmental Toxicity Potential of ToxCast Chemicals (ACT meeting)

EPA Science Inventory

Worldwide initiatives to screen for toxicity potential among the thousands of chemicals currently in use require inexpensive and high-throughput in vitro models to meet their goals. The devTOX quickPredict platform is an in vitro human pluripotent stem cell-based assay used to as...

The stem cell secretome and its role in brain repair.

PubMed

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

2013-12-01

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

A stem cell apostasy: A tale of 4 H words

PubMed Central

Quesenberry, Peter J.; Goldberg, Laura R.; Dooner, Mark S.

2014-01-01

The field of hematopoietic stem cell biology has become increasingly dominated by the pursuit and study of highly purified populations of hematopoietic stem cells (HSCs). Such HSCs are typically isolated based on their cell surface marker expression patterns and ultimately defined by their multipotency and capacity for self-generation. However, even with progressively more stringent stem cell separation techniques, the resultant HSC population remains heterogeneous with respect to both self-renewal and differentiation capacity. Critical studies on un-separated whole bone marrow (WBM) have definitively shown that long-term engraftable hematopoietic stem cells are in active cell cycle and thus continually changing phenotype. Therefore, they cannot be purified by current approaches dependent on stable surface epitope expression because the surface markers are continually changing as well. These critical cycling cells are discarded with current stem cell purifications. Despite this, research defining such characteristics as self-renewal capacity, lineage-commitment, bone marrow niches, and proliferative state of HSCs continues to focus predominantly on this small sub-population of purified marrow cells. This review discusses the research leading to the hierarchical model of hematopoiesis and questions the dogmas pertaining to HSC quiescence and purification. PMID:25183450