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.

Cellular and epigenetic drivers of stem cell ageing.

PubMed

Ermolaeva, Maria; Neri, Francesco; Ori, Alessandro; Rudolph, K Lenhard

2018-06-01

Adult tissue stem cells have a pivotal role in tissue maintenance and regeneration throughout the lifespan of multicellular organisms. Loss of tissue homeostasis during post-reproductive lifespan is caused, at least in part, by a decline in stem cell function and is associated with an increased incidence of diseases. Hallmarks of ageing include the accumulation of molecular damage, failure of quality control systems, metabolic changes and alterations in epigenome stability. In this Review, we discuss recent evidence in support of a novel concept whereby cell-intrinsic damage that accumulates during ageing and cell-extrinsic changes in ageing stem cell niches and the blood result in modifications of the stem cell epigenome. These cumulative epigenetic alterations in stem cells might be the cause of the deregulation of developmental pathways seen during ageing. In turn, they could confer a selective advantage to mutant and epigenetically drifted stem cells with altered self-renewal and functions, which contribute to the development of ageing-associated organ dysfunction and disease.

Lung Regeneration: Endogenous and Exogenous Stem Cell Mediated Therapeutic Approaches.

PubMed

Akram, Khondoker M; Patel, Neil; Spiteri, Monica A; Forsyth, Nicholas R

2016-01-19

The tissue turnover of unperturbed adult lung is remarkably slow. However, after injury or insult, a specialised group of facultative lung progenitors become activated to replenish damaged tissue through a reparative process called regeneration. Disruption in this process results in healing by fibrosis causing aberrant lung remodelling and organ dysfunction. Post-insult failure of regeneration leads to various incurable lung diseases including chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis. Therefore, identification of true endogenous lung progenitors/stem cells, and their regenerative pathway are crucial for next-generation therapeutic development. Recent studies provide exciting and novel insights into postnatal lung development and post-injury lung regeneration by native lung progenitors. Furthermore, exogenous application of bone marrow stem cells, embryonic stem cells and inducible pluripotent stem cells (iPSC) show evidences of their regenerative capacity in the repair of injured and diseased lungs. With the advent of modern tissue engineering techniques, whole lung regeneration in the lab using de-cellularised tissue scaffold and stem cells is now becoming reality. In this review, we will highlight the advancement of our understanding in lung regeneration and development of stem cell mediated therapeutic strategies in combating incurable lung diseases.

Clinical grade adult stem cell banking

PubMed Central

Thirumala, Sreedhar; Goebel, W Scott

2009-01-01

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

Representations of stem cell clinics on Twitter.

PubMed

Kamenova, Kalina; Reshef, Amir; Caulfield, Timothy

2014-12-01

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

Stem cells in dentistry--part I: stem cell sources.

PubMed

Egusa, Hiroshi; Sonoyama, Wataru; Nishimura, Masahiro; Atsuta, Ikiru; Akiyama, Kentaro

2012-07-01

Stem cells can self-renew and produce different cell types, thus providing new strategies to regenerate missing tissues and treat diseases. In the field of dentistry, adult mesenchymal stem/stromal cells (MSCs) have been identified in several oral and maxillofacial tissues, which suggests that the oral tissues are a rich source of stem cells, and oral stem and mucosal cells are expected to provide an ideal source for genetically reprogrammed cells such as induced pluripotent stem (iPS) cells. Furthermore, oral tissues are expected to be not only a source but also a therapeutic target for stem cells, as stem cell and tissue engineering therapies in dentistry continue to attract increasing clinical interest. Part I of this review outlines various types of intra- and extra-oral tissue-derived stem cells with regard to clinical availability and applications in dentistry. Additionally, appropriate sources of stem cells for regenerative dentistry are discussed with regard to differentiation capacity, accessibility and possible immunomodulatory properties. Copyright © 2012 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Effect of autologous adipose-derived mesenchymal stem cell therapy in the treatment of a post-traumatic chondral defect of the knee

PubMed Central

Freitag, Julien; Li, Douglas; Wickham, James; Shah, Kiran; Tenen, Abi

2017-01-01

Isolated chondral defects have a limited capacity to heal and predispose to the development of osteoarthritis. Current surgical management can be unpredictable in outcome. Improved understanding of the action of mesenchymal stem cells (MSCs) has seen renewed interest in their role in cartilage repair. A 26-year-old athlete presented with a post-traumatic, isolated patella chondral defect. The patient underwent an arthroscopy with removal of a chondral loose body. After failure to symptomatically improve 12 months following surgery, the patient received intra-articular autologous adipose-derived mesenchymal stem cell (ADMSC) therapy. PMID:29038190

Chromatin remodeling in stem cell maintenance in Arabidopsis thaliana.

PubMed

Shen, Wen-Hui; Xu, Lin

2009-07-01

Pluripotent stem cells are able to both self-renew and generate undifferentiated cells for the formation of new tissues and organs. In higher plants, stem cells found in the shoot apical meristem (SAM) and the root apical meristem (RAM) are origins of organogenesis occurring post-embryonically. It is important to understand how the regulation of stem cell fate is coordinated to enable the meristem to constantly generate different types of lateral organs. Much knowledge has accumulated on specific transcription factors controlling SAM and RAM activity. Here, we review recent evidences for a role of chromatin remodeling in the maintenance of stable expression states of transcription factor genes and the control of stem cell activity in Arabidopsis.

Safety and efficacy of cardiopoietic stem cells in the treatment of post-infarction left-ventricular dysfunction - From cardioprotection to functional repair in a translational pig infarction model.

PubMed

Emmert, Maximilian Y; Wolint, Petra; Jakab, Andras; Sheehy, Sean P; Pasqualini, Francesco S; Nguyen, Thi Dan Linh; Hilbe, Monika; Seifert, Burkhardt; Weber, Benedikt; Brokopp, Chad E; Macejovska, Dominika; Caliskan, Etem; von Eckardstein, Arnold; Schwartlander, Ruth; Vogel, Viola; Falk, Volkmar; Parker, Kevin Kit; Gyöngyösi, Mariann; Hoerstrup, Simon P

2017-04-01

To date, clinical success of cardiac cell-therapies remains limited. To enhance the cardioreparative properties of stem cells, the concept of lineage-specification through cardiopoietic-guidance has been recently suggested. However, so far, only results from murine studies and from a clinical pilot-trial in chronic heart-failure (CHF) are available, while systematic evidence of its therapeutic-efficacy is still lacking. Importantly, also no data from large animals or for other indications are available. Therefore, we here investigate the therapeutic-efficacy of human cardiopoietic stem cells in the treatment of post-infarction LV-dysfunction using a translational pig-model. Using growth-factor priming, lineage-specification of human bone-marrow derived MSCs was achieved to generate cardiopoietic stem cells according to GMP-compliant protocols. Thereafter, pigs with post-infarction LV-dysfunction (sub-acute phase;1-month) were randomized to either receive transcatheter NOGA 3D electromechanical-mapping guided intramyocardial transplantation of cardiopoietic cells or saline (control). After 30days, cardiac MRI (cMRI) was performed for functional evaluation and in-vivo cell-tracking. This approach was coupled with a comprehensive post-mortem cell-fate and mode-of-repair analysis. Cardiopoietic cell therapy was safe and ejection-fraction was significantly higher when compared to controls (p = 0.012). It further prevented maladaptive LV-remodeling and revealed a significantly lower relative and total infarct-size (p = 0.043 and p = 0.012). As in-vivo tracking and post-mortem analysis displayed only limited intramyocardial cardiopoietic cell-integration, the significant induction of neo-angiogenesis (∼40% higher; p = 0.003) and recruitment of endogenous progenitors (∼2.5x higher; p = 0.008) to the infarct border-zone appeared to be the major modes-of-repair. This is the first report using a pre-clinical large animal-model to demonstrate the safety and

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.

Caspase inhibitors increase the rate of recovery of neural stem/progenitor cells from post-mortem rat brains stored at room temperature.

PubMed

Hasegawa, Atsuko; Yamada, Chikako; Tani, Miho; Hirano, Shun-ichiro; Tokumoto, Yasuhito; Miyake, Jun

2009-06-01

To match the demand of regenerative medicine for nerve system, collection of stem cells from the post-mortem body is one of the most practical ways. In this study, the storage condition of the post-mortem body was examined. We prepared neural stem/progenitor cells (NSPCs) from post-mortem rat brains stored at different temperatures. When brains were stored at 4 degrees C, for one week, we were able to obtain neurospheres (a spheroid body containing NSPCs) by stimulation of cells with epidermal growth factor (EGF). Incremental increases in storage temperature decreased the rate of appearance of neurospheres. Within 48 h at 15 degrees C, 24 h at 25 degrees C, in both condition, we were able to recover NSPCs from post-mortem rat brains. At 15 degrees C, 90% of neurosphere-forming activity was lost within 24 h. However, even after 24 h at 25 degrees C, 2% neurosphere-forming activity remained. After 6 h of death, there was very little difference between the rates of NSPC recovery at 4 degrees C and 25 degrees C. Addition of caspase inhibitors to both the rat brain storage solution and the NSPC culture medium increased the rate of neurosphere-forming activity. In particular, an inhibitor of caspase-8 activity increased the NSPC recovery rate approximately three-fold, with no accompanying detrimental effects on neural differentiation in vitro.

Regulation of Mammary Stem Cell Quiescence via Post-Translational Modification of DeltaNp63alpha

DTIC Science & Technology

2012-12-01

This document is the Annual Summary Report on the training grant awarded to Andrew DeCastro entitled Regulation of Mammary Stem Cell Quiescence via...screen) mediated phosphorylation of deltaNPdelta3 on stem cell behavior and mitotic activity. Task 1 aims to determine the effects of wild-type, phospho...ablative and phospho-mimetic alleles of deltaNP63delta phosphorylation on stem cell behavior in vitro. Thus far, we demonstrate that stem cell enriched

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

Types of Stem Cells

MedlinePlus

... Cell Glossary Search Toggle Nav Types of Stem Cells Stem cells are the foundation from which all ... About Stem Cells > Types of Stem Cells Stem cells Stem cells are the foundation for every organ ...

Aging, metabolism and stem cells: Spotlight on muscle stem cells.

PubMed

García-Prat, Laura; Muñoz-Cánoves, Pura

2017-04-15

All tissues and organs undergo a progressive regenerative decline as they age. This decline has been mainly attributed to loss of stem cell number and/or function, and both stem cell-intrinsic changes and alterations in local niches and/or systemic environment over time are known to contribute to the stem cell aging phenotype. Advancing in the molecular understanding of the deterioration of stem cell cells with aging is key for targeting the specific causes of tissue regenerative dysfunction at advanced stages of life. Here, we revise exciting recent findings on why stem cells age and the consequences on tissue regeneration, with a special focus on regeneration of skeletal muscle. We also highlight newly identified common molecular pathways affecting diverse types of aging stem cells, such as altered proteostasis, metabolism, or senescence entry, and discuss the questions raised by these findings. Finally, we comment on emerging stem cell rejuvenation strategies, principally emanating from studies on muscle stem cells, which will surely burst tissue regeneration research for future benefit of the increasing human aging population. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Stem cell biobanks.

PubMed

Bardelli, Silvana

2010-04-01

Stem cells contribute to innate healing and harbor a promising role for regenerative medicine. Stem cell banking through long-term storage of different stem cell platforms represents a fundamental source to preserve original features of stem cells for patient-specific clinical applications. Stem cell research and clinical translation constitute fundamental and indivisible modules catalyzed through biobanking activity, generating a return of investment.

Stem Cell Basics

MedlinePlus

... Tips Info Center Research Topics Federal Policy Glossary Stem Cell Information General Information Clinical Trials Funding Information Current ... Basics » Stem Cell Basics I. Back to top Stem Cell Basics I. Introduction: What are stem cells, and ...

Un(MaSC)ing Stem Cell Dynamics in Mammary Branching Morphogenesis.

PubMed

Greenwood, Erin; Wrenn, Emma D; Cheung, Kevin J

2017-02-27

The properties of stem cells that participate in mammary gland branching morphogenesis remain contested. Reporting in Nature, Scheele et al. (2017) establish a model for post-pubertal mammary branching morphogenesis in which position-dependent, lineage-restricted stem cells undergo cell mixing in order to contribute to long-term growth. Copyright © 2017 Elsevier Inc. All rights reserved.

Haematopoietic stem and progenitor cells from human pluripotent stem cells

PubMed Central

Sugimura, Ryohichi; Jha, Deepak Kumar; Han, Areum; Soria-Valles, Clara; da Rocha, Edroaldo Lummertz; Lu, Yi-Fen; Goettel, Jeremy A.; Serrao, Erik; Rowe, R. Grant; Malleshaiah, Mohan; Wong, Irene; Sousa, Patricia; Zhu, Ted N.; Ditadi, Andrea; Keller, Gordon; Engelman, Alan N.; Snapper, Scott B.; Doulatov, Sergei; Daley, George Q.

2018-01-01

A variety of tissue lineages can be differentiated from pluripotent stem cells by mimicking embryonic development through stepwise exposure to morphogens, or by conversion of one differentiated cell type into another by enforced expression of master transcription factors. Here, to yield functional human haematopoietic stem cells, we perform morphogen-directed differentiation of human pluripotent stem cells into haemogenic endothelium followed by screening of 26 candidate haematopoietic stem-cell-specifying transcription factors for their capacity to promote multi-lineage haematopoietic engraftment in mouse hosts. We recover seven transcription factors (ERG, HOXA5, HOXA9, HOXA10, LCOR, RUNX1 and SPI1) that are sufficient to convert haemogenic endothelium into haematopoietic stem and progenitor cells that engraft myeloid, B and T cells in primary and secondary mouse recipients. Our combined approach of morphogen-driven differentiation and transcription-factor-mediated cell fate conversion produces haematopoietic stem and progenitor cells from pluripotent stem cells and holds promise for modelling haematopoietic disease in humanized mice and for therapeutic strategies in genetic blood disorders. PMID:28514439

Advising patients seeking stem cell interventions for multiple sclerosis.

PubMed

von Wunster, Beatrice; Bailey, Steven; Wilkins, Alastair; Marks, David I; Scolding, Neil J; Rice, Claire M

2018-05-30

Given the intuitive potential of stem cell therapy and limitations of current treatment options for progressive multiple sclerosis (MS), it is not surprising that patients consider undertaking significant clinical and financial risks to access stem cell transplantation. However, while increasing evidence supports autologous haematopoietic stem cell transplantation (AHSCT) in aggressive relapsing-remitting MS, interventions employing haematopoietic or other stem cells should otherwise be considered experimental and recommended only in the context of a properly regulated clinical study. Understandably, most neurologists are unfamiliar with AHSCT procedures and the specific requirements for quality assurance and safety standards, as well as post-procedure precautions and follow-up. Consequently they may feel ill-equipped to advise patients. Here, we highlight important points for discussion in consultations with patients considering stem cell 'tourism' for MS. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

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

Learn About Stem Cells

MedlinePlus

... Handbook Stem Cell Glossary Search Toggle Nav Stem Cell Basics Stem cells are the foundation from which ... Home > Learn About Stem Cells > Stem Cell Basics Cells in the human body The human body comprises ...

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.

Fake news portrayals of stem cells and stem cell research.

PubMed

Marcon, Alessandro R; Murdoch, Blake; Caulfield, Timothy

2017-10-01

This study examines how stem cells and stem cell research are portrayed on websites deemed to be purveyors of distorted and dubious information. Content analysis was conducted on 224 articles from 2015 to 2016, compiled by searching with the keywords 'stem cell(s)' on a list of websites flagged for containing either 'fake' or 'junk science' news. Articles contained various exaggerated positive and negative claims about stem cells and stem cell science, health and science related conspiracy theories, and statements promoting fear and mistrust of conventional medicine. Findings demonstrate the existence of organized misinformation networks, which may lead the public away from accurate information and facilitate a polarization of public discourse.

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

PubMed

Cornelison, Ddw; Perdiguero, Eusebio

2017-01-01

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

Comparable post-relapse outcomes between haploidentical and matched related donor allogeneic stem cell transplantation.

PubMed

Ma, Y-R; Xu, L-P; Zhang, X-H; Yan, C-H; Wang, Y; Wang, F-R; Wang, J-Z; Chen, Y; Han, W; Chen, Y-H; Chen, H; Liu, K-Y; Huang, X-J

2017-03-01

We investigated the impact of donor type on post-relapse survival (PRS) in 85 patients with hematological relapse after their first allogeneic hematological stem cell transplantation (allo-HSCT) for hematological malignancy. The median follow-up was 64 months among survivors. Both 3-year overall survival and 3-year PRS were similar in haploidentical donor (HID) and matched sibling donor (MRD) transplantation (13.0%±4.7% vs 19.4%±7.1%, P=0.913 and 7.7±3.9% vs 9.7±5.3%, P= 0.667). Higher rates of post-relapse grade II-IV and III-IV acute GvHD (aGvHD) were observed in HID transplantation patients. A higher cumulative incidence of post-relapse extensive chronic GvHD was also observed for HID transplantation patients. Multivariate analyses confirmed that treatment including donor lymphocyte infusion (DLI), late relapse >1 year, and in first CR at transplantation were associated with superior PRS (P=0.012, hazard ratio (HR)=0.527 (0.320-0.866)); P=0.033, HR=0.534 (0.300-0.952) and P=0.046, HR=0.630 (0.400-0.992). The data suggest that post-relapse outcomes are comparable in HID and MRD transplantation, and that DLI is safe for relapsed patients after haploidentical transplantation.

Stem Cell Pathology.

PubMed

Fu, Dah-Jiun; Miller, Andrew D; Southard, Teresa L; Flesken-Nikitin, Andrea; Ellenson, Lora H; Nikitin, Alexander Yu

2018-01-24

Rapid advances in stem cell biology and regenerative medicine have opened new opportunities for better understanding disease pathogenesis and the development of new diagnostic, prognostic, and treatment approaches. Many stem cell niches are well defined anatomically, thereby allowing their routine pathological evaluation during disease initiation and progression. Evaluation of the consequences of genetic manipulations in stem cells and investigation of the roles of stem cells in regenerative medicine and pathogenesis of various diseases such as cancer require significant expertise in pathology for accurate interpretation of novel findings. Therefore, there is an urgent need for developing stem cell pathology as a discipline to facilitate stem cell research and regenerative medicine. This review provides examples of anatomically defined niches suitable for evaluation by diagnostic pathologists, describes neoplastic lesions associated with them, and discusses further directions of stem cell pathology.

Human mesenchymal stem cells promote CD34+ hematopoietic stem cell proliferation with preserved red blood cell differentiation capacity.

PubMed

Lau, Show Xuan; Leong, Yin Yee; Ng, Wai Hoe; Ng, Albert Wee Po; Ismail, Ida Shazrina; Yusoff, Narazah Mohd; Ramasamy, Rajesh; Tan, Jun Jie

2017-06-01

Studies showed that co-transplantation of mesenchymal stem cells (MSCs) and cord blood-derived CD34 + hematopoietic stem cells (HSCs) offered greater therapeutic effects but little is known regarding the effects of human Wharton's jelly derived MSCs on HSC expansion and red blood cell (RBC) generation in vitro. This study aimed to investigate the effects of MSCs on HSC expansion and differentiation. HSCs were co-cultured with MSCs or with 10% MSCs-derived conditioned medium, with HSCs cultured under standard medium served as a control. Cell expansion rates, number of mononuclear cell post-expansion and number of enucleated cells post-differentiation were evaluated. HSCs showed superior proliferation in the presence of MSC with mean expansion rate of 3.5 × 10 8  ± 1.8 × 10 7 after day 7 compared to the conditioned medium and the control group (8.9 × 10 7  ± 1.1 × 10 8 and 7.0 × 10 7  ± 3.3 × 10 6 respectively, P < 0.001). Although no significant differences in RBC differentiation were observed between groups at passage IV, the number of enucleated cell was greater compared to earlier passages, indicating successful RBC differentiation. Cord blood-derived CD34 + HSCs can be greatly expanded by co-culturing with MSCs without affecting the RBC differentiation capability, suggesting the importance of direct MSC-HSCs contact in HSC expansion and RBC differentiation. © 2017 International Federation for Cell Biology.

CMV-specific immune reconstitution following allogeneic stem cell transplantation

PubMed Central

Blyth, Emily; Withers, Barbara; Clancy, Leighton; Gottlieb, David

2016-01-01

ABSTRACT Cytomegalovirus (CMV) remains a major contributor to morbidity and mortality following allogeneic haemopoietic stem cell transplant (HSCT) despite widespread use of viraemia monitoring and pre-emptive antiviral therapy. Uncontrolled viral replication occurs primarily in the first 100 d post transplant but this high risk period can extend to many months if immune recovery is delayed. The re-establishment of a functional population of cellular effectors is essential for control of virus replication and depends on recipient and donor serostatus, the stem cell source, degree of HLA matching and post-transplant factors such as CMV antigen exposure, presence of GVHD and ongoing use of immune suppression. A number of immune monitoring assays exist but have not yet become widely accessible for routine clinical use. Vaccination, adoptive transfer of CMV specific T cells and a number of graft engineering processes are being evaluated to enhance of CMV specific immune recovery post HSCT. PMID:27580355

College Students' Conceptions of Stem Cells, Stem Cell Research, and Cloning

ERIC Educational Resources Information Center

Concannon, James P.; Siegel, Marcelle A.; Halverson, Kristy; Freyermuth, Sharyn

2010-01-01

In this study, we examined 96 undergraduate non-science majors' conceptions of stem cells, stem cell research, and cloning. This study was performed at a large, Midwest, research extensive university. Participants in the study were asked to answer 23 questions relating to stem cells, stem cell research, and cloning in an on-line assessment before…

MicroRNAs in Control of Stem Cells in Normal and Malignant Hematopoiesis

PubMed Central

Roden, Christine; Lu, Jun

2016-01-01

Studies on hematopoietic stem cells (HSCs) and leukemia stem cells (LSCs) have helped to establish the paradigms of normal and cancer stem cell concepts. For both HSCs and LSCs, specific gene expression programs endowed by their epigenome functionally distinguish them from their differentiated progenies. MicroRNAs (miRNAs), as a class of small non-coding RNAs, act to control post-transcriptional gene expression. Research in the past decade has yielded exciting findings elucidating the roles of miRNAs in control of multiple facets of HSC and LSC biology. Here we review recent progresses on the functions of miRNAs in HSC emergence during development, HSC switch from a fetal/neonatal program to an adult program, HSC self-renewal and quiescence, HSC aging, HSC niche, and malignant stem cells. While multiple different miRNAs regulate a diverse array of targets, two common themes emerge in HSC and LSC biology: miRNA mediated regulation of epigenetic machinery and cell signaling pathways. In addition, we propose that miRNAs themselves behave like epigenetic regulators, as they possess key biochemical and biological properties that can provide both stability and alterability to the epigenetic program. Overall, the studies of miRNAs in stem cells in the hematologic contexts not only provide key understandings to post-transcriptional gene regulation mechanisms in HSCs and LSCs, but also will lend key insights for other stem cell fields. PMID:27547713

Electrospun Collagen/Silk Tissue Engineering Scaffolds: Fiber Fabrication, Post-Treatment Optimization, and Application in Neural Differentiation of Stem Cells

NASA Astrophysics Data System (ADS)

Zhu, Bofan

Biocompatible scaffolds mimicking the locally aligned fibrous structure of native extracellular matrix (ECM) are in high demand in tissue engineering. In this thesis research, unidirectionally aligned fibers were generated via a home-built electrospinning system. Collagen type I, as a major ECM component, was chosen in this study due to its support of cell proliferation and promotion of neuroectodermal commitment in stem cell differentiation. Synthetic dragline silk proteins, as biopolymers with remarkable tensile strength and superior elasticity, were also used as a model material. Good alignment, controllable fiber size and morphology, as well as a desirable deposition density of fibers were achieved via the optimization of solution and electrospinning parameters. The incorporation of silk proteins into collagen was found to significantly enhance mechanical properties and stability of electrospun fibers. Glutaraldehyde (GA) vapor post-treatment was demonstrated as a simple and effective way to tune the properties of collagen/silk fibers without changing their chemical composition. With 6-12 hours GA treatment, electrospun collagen/silk fibers were not only biocompatible, but could also effectively induce the polarization and neural commitment of stem cells, which were optimized on collagen rich fibers due to the unique combination of biochemical and biophysical cues imposed to cells. Taken together, electrospun collagen rich composite fibers are mechanically strong, stable and provide excellent cell adhesion. The unidirectionally aligned fibers can accelerate neural differentiation of stem cells, representing a promising therapy for neural tissue degenerative diseases and nerve injuries.

[Proteins support stem cells - use of protein therapeutics in hematopoietic stem cell transplantation].

PubMed

Meyer, Sara Christina; Stern, Martin

2011-11-01

Hematopoietic stem cell transplantation (HSCT) has evolved from a largely experimental therapeutic approach three decades ago to a well-established therapy today for many malignant and non-malignant disorders of the hematopoietic and the immune system. Although it is per se a therapy by transmission of cells, protein therapeutics such as growth factors and antibodies are relevant in all phases of a HSCT and substantially contribute to the success of this often only curative treatment. This review discusses HSCT with a particular focus on the protein therapeutics involved. Granulocyte colony stimulating factor (G-CSF) for mobilization of stem cells to the peripheral blood, the polyclonal anti-T-cell globulin (ATG) and the monoclonal antibodies alemtuzumab and etanercept for prophylaxis and therapy of graft versus host disease (GvHD) are highlighted. Also rituximab, palivizumab and polyclonal intravenous immunoglobulins for treating infections in post-transplant patients are discussed. Since our understanding of cell surface receptors, cytokine and signaling pathways is increasing, there will emerge new targets for directed therapy by proteins in the future. They may have the potential to further improve the success and to widen theapplication of HSCT.

Plant stem cell niches.

PubMed

Stahl, Yvonne; Simon, Rüdiger

2005-01-01

Stem cells are required to support the indeterminate growth style of plants. Meristems are a plants stem cell niches that foster stem cell survival and the production of descendants destined for differentiation. In shoot meristems, stem cell fate is decided at the populational level. The size of the stem cell domain at the meristem tip depends on signals that are exchanged with cells of the organizing centre underneath. In root meristems, individual stem cells are controlled by direct interaction with cells of the quiescent centre that lie in the immediate neighbourhood. Analysis of the interactions and signaling processes in the stem cell niches has delivered some insights into the molecules that are involved and revealed that the two major niches for plant stem cells are more similar than anticipated.

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.

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.

What is a stem cell?

PubMed

Slack, Jonathan M W

2018-05-15

The historical roots of the stem cell concept are traced with respect to its usage in embryology and in hematology. The modern consensus definition of stem cells, comprising both pluripotent stem cells in culture and tissue-specific stem cells in vivo, is explained and explored. Methods for identifying stem cells are discussed with respect to cell surface markers, telomerase, label retention and transplantability, and properties of the stem cell niche are explored. The CreER method for identifying stem cells in vivo is explained, as is evidence in favor of a stochastic rather than an obligate asymmetric form of cell division. In conclusion, it is found that stem cells do not possess any unique and specific molecular markers; and stem cell behavior depends on the environment of the cell as well as the stem cell's intrinsic qualities. Furthermore, the stochastic mode of division implies that stem cell behavior is a property of a cell population not of an individual cell. In this sense, stem cells do not exist in isolation but only as a part of multicellular system. This article is categorized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches Adult Stem Cells, Tissue Renewal, and Regeneration > Methods and Principles Adult Stem Cells, Tissue Renewal, and Regeneration > Environmental Control of Stem Cells. © 2018 Wiley Periodicals, Inc.

Biosimilar G-CSF Based Mobilization of Peripheral Blood Hematopoietic Stem Cells for Autologous and Allogeneic Stem Cell Transplantation

PubMed Central

Schmitt, Michael; Publicover, Amy; Orchard, Kim H; Görlach, Matthias; Wang, Lei; Schmitt, Anita; Mani, Jiju; Tsirigotis, Panagiotis; Kuriakose, Reeba; Nagler, Arnon

2014-01-01

The use of granulocyte colony stimulating factor (G-CSF) biosimilars for peripheral blood hematopoietic stem cell (PBSC) mobilization has stimulated an ongoing debate regarding their efficacy and safety. However, the use of biosimilar G-CSF was approved by the European Medicines Agency (EMA) for all the registered indications of the originator G-CSF (Neupogen®) including mobilization of stem cells. Here, we performed a comprehensive review of published reports on the use of biosimilar G-CSF covering patients with hematological malignancies as well as healthy donors that underwent stem cell mobilization at multiple centers using site-specific non-randomized regimens with a biosimilar G-CSF in the autologous and allogeneic setting. A total of 904 patients mostly with hematological malignancies as well as healthy donors underwent successful autologous or allogeneic stem cell mobilization, respectively, using a biosimilar G-CSF (520 with Ratiograstim®/Tevagrastim, 384 with Zarzio®). The indication for stem cell mobilization in hematology patients included 326 patients with multiple myeloma, 273 with Non-Hodgkin's lymphoma (NHL), 79 with Hodgkin's lymphoma (HL), and other disease. 156 sibling or volunteer unrelated donors were mobilized using biosimilar G-CSF. Mobilization resulted in good mobilization of CD34+ stem cells with side effects similar to originator G-CSF. Post transplantation engraftment did not significantly differ from results previously documented with the originator G-CSF. The side effects experienced by the patients or donors mobilized by biosimilar G-CSF were minimal and were comparable to those of originator G-CSF. In summary, the efficacy of biosimilar G-CSFs in terms of PBSC yield as well as their toxicity profile are equivalent to historical data with the reference G-CSF. PMID:24505236

Biosimilar G-CSF based mobilization of peripheral blood hematopoietic stem cells for autologous and allogeneic stem cell transplantation.

PubMed

Schmitt, Michael; Publicover, Amy; Orchard, Kim H; Görlach, Matthias; Wang, Lei; Schmitt, Anita; Mani, Jiju; Tsirigotis, Panagiotis; Kuriakose, Reeba; Nagler, Arnon

2014-01-01

The use of granulocyte colony stimulating factor (G-CSF) biosimilars for peripheral blood hematopoietic stem cell (PBSC) mobilization has stimulated an ongoing debate regarding their efficacy and safety. However, the use of biosimilar G-CSF was approved by the European Medicines Agency (EMA) for all the registered indications of the originator G-CSF (Neupogen (®) ) including mobilization of stem cells. Here, we performed a comprehensive review of published reports on the use of biosimilar G-CSF covering patients with hematological malignancies as well as healthy donors that underwent stem cell mobilization at multiple centers using site-specific non-randomized regimens with a biosimilar G-CSF in the autologous and allogeneic setting. A total of 904 patients mostly with hematological malignancies as well as healthy donors underwent successful autologous or allogeneic stem cell mobilization, respectively, using a biosimilar G-CSF (520 with Ratiograstim®/Tevagrastim, 384 with Zarzio®). The indication for stem cell mobilization in hematology patients included 326 patients with multiple myeloma, 273 with Non-Hodgkin's lymphoma (NHL), 79 with Hodgkin's lymphoma (HL), and other disease. 156 sibling or volunteer unrelated donors were mobilized using biosimilar G-CSF. Mobilization resulted in good mobilization of CD34+ stem cells with side effects similar to originator G-CSF. Post transplantation engraftment did not significantly differ from results previously documented with the originator G-CSF. The side effects experienced by the patients or donors mobilized by biosimilar G-CSF were minimal and were comparable to those of originator G-CSF. In summary, the efficacy of biosimilar G-CSFs in terms of PBSC yield as well as their toxicity profile are equivalent to historical data with the reference G-CSF.

Social media & stem cell science: examining the discourse.

PubMed

Adams, Amy; Lomax, Geoffrey; Santarini, Anthony

2011-11-01

Research suggests that the representation of scientific and medical issues in the traditional media such as newspapers, TV and radio is an important determinant of public opinion and related public policy outcomes, particularly with regard to attitudes toward stem cell research. With the emergence of social media, the discursive space around public policy issues has expanded to include a new demographic of media consumer who is directly involved in political action. However, little is known about the influence of social media on scientific public policy conversations. We analyzed Twitter posts on two topics relating to stem cell science and policy according to the originator and tone of the tweet, and whether the tweet was intended to be neutral or to further a stated policy position. This analysis provides a means for clarifying the role of social media in influencing public opinion of policy issues such as stem cell research and offers organizations a better understanding of how to more effectively apply social media to advancing their stem cell policy positions.

Stem cells and reproduction.

PubMed

Du, Hongling; Taylor, Hugh S

2010-06-01

To review the latest developments in reproductive tract stem cell biology. In 2004, two studies indicated that ovaries contain stem cells which form oocytes in adults and that can be cultured in vitro into mature oocytes. A live birth after orthotopic transplantation of cryopreserved ovarian tissue in a woman whose ovaries were damaged by chemotherapy demonstrates the clinical potential of these cells. In the same year, another study provided novel evidence of endometrial regeneration by stem cells in women who received bone marrow transplants. This finding has potential for the use in treatment of uterine disorders. It also supports a new theory for the cause of endometriosis, which may have its origin in ectopic transdifferentiation of stem cells. Several recent studies have demonstrated that fetal cells enter the maternal circulation and generate microchimerism in the mother. The uterus is a dynamic organ permeable to fetal stem cells, capable of transdifferentiation and an end organ in which bone marrow stem cells may differentiate. Finally stem cell transformation can be an underlying cause of ovarian cancer. Whereas we are just beginning to understand stem cells, the potential implications of stem cells to reproductive biology and medicine are apparent.

Stem cells and bone diseases: new tools, new perspective.

PubMed

Riminucci, Mara; Remoli, Cristina; Robey, Pamela G; Bianco, Paolo

2015-01-01

Postnatal skeletal stem cells are a unique class of progenitors with biological properties that extend well beyond the limits of stemness as commonly defined. Skeletal stem cells sustain skeletal tissue homeostasis, organize and maintain the complex architectural structure of the bone marrow microenvironment and provide a niche for hematopoietic progenitor cells. The identification of stem cells in the human post-natal skeleton has profoundly changed our approach to the physiology and pathology of this system. Skeletal diseases have been long interpreted essentially in terms of defective function of differentiated cells and/or abnormal turnover of the matrix that they produce. The notion of a skeletal stem cell has brought forth multiple, novel concepts in skeletal biology that provide potential alternative concepts. At the same time, the recognition of the complex functions played by skeletal progenitors, such as the structural and functional organization of the bone marrow, has provided an innovative, unifying perspective for understanding bone and bone marrow changes simultaneously occurring in many disorders. Finally, the possibility to isolate and highly enrich for skeletal progenitors, enables us to reproduce perfectly normal or pathological organ miniatures. These, in turn, provide suitable models to investigate and manipulate the pathogenetic mechanisms of many genetic and non-genetic skeletal diseases. This article is part of a Special Issue entitled Stem cells and Bone. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

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.

Combination cell therapy with mesenchymal stem cells and neural stem cells for brain stroke in rats.

PubMed

Hosseini, Seyed Mojtaba; Farahmandnia, Mohammad; Razi, Zahra; Delavari, Somayeh; Shakibajahromi, Benafsheh; Sarvestani, Fatemeh Sabet; Kazemi, Sepehr; Semsar, Maryam

2015-05-01

Brain stroke is the second most important events that lead to disability and morbidity these days. Although, stroke is important, there is no treatment for curing this problem. Nowadays, cell therapy has opened a new window for treating central nervous system disease. In some previous studies the Mesenchymal stem cells and neural stem cells. In this study, we have designed an experiment to assess the combination cell therapy (Mesenchymal and Neural stem cells) effects on brain stroke. The Mesenchymal stem cells were isolated from adult rat bone marrow and the neural stem cells were isolated from ganglion eminence of rat embryo 14 days. The Mesenchymal stem cells were injected 1 day after middle cerebral artery occlusion (MCAO) and the neural stem cells transplanted 7 day after MCAO. After 28 days, the neurological outcomes and brain lesion volumes were evaluated. Also, the activity of Caspase 3 was assessed in different groups. The group which received combination cell therapy had better neurological examination and less brain lesion. Also the combination cell therapy group had the least Caspase 3 activity among the groups. The combination cell therapy is more effective than Mesenchymal stem cell therapy and neural stem cell therapy separately in treating the brain stroke in rats.

The Diverse Roles of Hydrogel Mechanics in Injectable Stem Cell Transplantation.

PubMed

Foster, Abbygail A; Marquardt, Laura M; Heilshorn, Sarah C

2017-02-01

Stem cell delivery by local injection has tremendous potential as a regenerative therapy but has seen limited clinical success. Several mechanical challenges hinder therapeutic efficacy throughout all stages of cell transplantation, including mechanical forces during injection and loss of mechanical support post-injection. Recent studies have begun exploring the use of biomaterials, in particular hydrogels, to enhance stem cell transplantation by addressing the often-conflicting mechanical requirements associated with each stage of the transplantation process. This review explores recent biomaterial approaches to improve the therapeutic efficacy of stem cells delivered through local injection, with a focus on strategies that specifically address the mechanical challenges that result in cell death and/or limit therapeutic function throughout the stages of transplantation.

Haemopoietic stem cells.

PubMed

Bellantuono, Ilaria

2004-04-01

Considerable effort has been made in recent years in understanding the mechanisms that govern stem cell generation, proliferation, self-renewal, commitment and lately plasticity. In the development of the haemopoietic system during embryonic and fetal life the notion of different pools of stem cells arising from the endothelium is gaining consensus. Gene expression profiling of populations of stem cells is bringing to light categories of genes important for self-renewal or commitment. Besides the role of transcription factors in lineage decision, the role of soluble factors and transmembrane proteins, very active at the time of embryo development, are taking central stage in the maintenance and in vitro expansion of haemopoietic stem cells (HSCs). The hierarchical model of haemopoietic development is being questioned with reports of lineage switching and plasticity of haemopoietic stem cells to non-haemopoietic cells. Yet the understanding of the overall process is still very fragmented and hypothetical. This is mainly due to the absence of appropriate markers to enable selection of homogeneous stem cell populations and the need to rely on retrospective functional assays, able only to determine the overall behaviour of a population of cells. This review is intended to be an overview of the haemopoietic system and a critical re-visitation of issues such as plasticity and self-renewal important for therapeutic applications of haemopoietic stem cells.

Plant stem cell niches.

PubMed

Aichinger, Ernst; Kornet, Noortje; Friedrich, Thomas; Laux, Thomas

2012-01-01

Multicellular organisms possess pluripotent stem cells to form new organs, replenish the daily loss of cells, or regenerate organs after injury. Stem cells are maintained in specific environments, the stem cell niches, that provide signals to block differentiation. In plants, stem cell niches are situated in the shoot, root, and vascular meristems-self-perpetuating units of organ formation. Plants' lifelong activity-which, as in the case of trees, can extend over more than a thousand years-requires that a robust regulatory network keep the balance between pluripotent stem cells and differentiating descendants. In this review, we focus on current models in plant stem cell research elaborated during the past two decades, mainly in the model plant Arabidopsis thaliana. We address the roles of mobile signals on transcriptional modules involved in balancing cell fates. In addition, we discuss shared features of and differences between the distinct stem cell niches of Arabidopsis.

Development of hematopoietic stem and progenitor cells from human pluripotent stem cells.

PubMed

Chen, Tong; Wang, Fen; Wu, Mengyao; Wang, Zack Z

2015-07-01

Human pluripotent stem cells (hPSCs), including human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs), provide a new cell source for regenerative medicine, disease modeling, drug discovery, and preclinical toxicity screening. Understanding of the onset and the sequential process of hematopoietic cells from differentiated hPSCs will enable the achievement of personalized medicine and provide an in vitro platform for studying of human hematopoietic development and disease. During embryogenesis, hemogenic endothelial cells, a specified subset of endothelial cells in embryonic endothelium, are the primary source of multipotent hematopoietic stem cells. In this review, we discuss current status in the generation of multipotent hematopoietic stem and progenitor cells from hPSCs via hemogenic endothelial cells. We also review the achievements in direct reprogramming from non-hematopoietic cells to hematopoietic stem and progenitor cells. Further characterization of hematopoietic differentiation in hPSCs will improve our understanding of blood development and expedite the development of hPSC-derived blood products for therapeutic purpose. © 2015 Wiley Periodicals, Inc.

Haemopoietic stem cell transplantation for acute lymphoblastic leukaemia.

PubMed

Popat, Uday; Carrum, George; Heslop, Helen E

2003-02-01

The majority of children and some adults with acute lymphocytic leukaemia (ALL) can be cured with current intensive chemotherapy regimens. For those patients who relapse or who do not achieve remission, allogeneic haemopoietic stem cell transplantation (HSCT) offers the best chance for long-term disease control. Different sources of haemopoietic stem cells including marrow, peripheral blood, and cord blood are now available and the introduction of subablative regimens has increased the number of patients who are transplant candidates. Relapse remains the major cause of transplant failure and immunotherapy strategies post-transplant to augment the graft versus leukaemia effect are being explored.

New frontiers in pediatric allogeneic stem cell transplantation

PubMed Central

Talano, Julie-An M.; Pulsipher, Michael A.; Symons, Heather J.; Militano, Olga; Shereck, Evan B.; Giller, Roger H.; Hancock, Laura; Morris, Erin; Cairo, Mitchell S.

2015-01-01

The inaugural meeting of “New Frontiers in Pediatric Allogeneic Stem Cell Transplantation” organized by the Pediatric Blood and Transplant Consortium (PBMTC) was held at the American Society of Pediatric Hematology and Oncology Annual Meeting. This meeting provided an international platform for physicians and investigators active in the research and utilization of pediatric allogeneic stem cell transplantation (AlloSCT) in children and adolescents with malignant and non-malignant disease, to share information and develop future collaborative strategies. The primary objectives of the conference included: 1) to present advances in AlloSCT in pediatric ALL and novel pre- and post-immunotherapy; 2) to highlight new strategies in alternative allogeneic stem cell donor sources for children and adolescents with non-malignant hematological disorders; 3) to discuss timing of immune reconstitution after AlloSCT and methods of facilitating more rapid recovery of immunity; 4) to identify strategies of utilizing AlloSCT in pediatric myeloproliferative disorders (MPD); 5) to develop diagnostic and therapeutic approaches to hematological complications post pediatric AlloSCT; 6) to enhance the understanding of new novel cellular therapeutic approaches to pediatric malignant and non-malignant hematological disorders; and 7) to discuss optimizing drug therapy in pediatric recipients of AlloSCT. This paper will provide a brief overview of the conference. PMID:24820213

Single-cell sequencing in stem cell biology.

PubMed

Wen, Lu; Tang, Fuchou

2016-04-15

Cell-to-cell variation and heterogeneity are fundamental and intrinsic characteristics of stem cell populations, but these differences are masked when bulk cells are used for omic analysis. Single-cell sequencing technologies serve as powerful tools to dissect cellular heterogeneity comprehensively and to identify distinct phenotypic cell types, even within a 'homogeneous' stem cell population. These technologies, including single-cell genome, epigenome, and transcriptome sequencing technologies, have been developing rapidly in recent years. The application of these methods to different types of stem cells, including pluripotent stem cells and tissue-specific stem cells, has led to exciting new findings in the stem cell field. In this review, we discuss the recent progress as well as future perspectives in the methodologies and applications of single-cell omic sequencing technologies.

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

PubMed Central

Mills, Jason C.; Sansom, Owen J.

2016-01-01

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

Stem cells - biological update and cell therapy progress

PubMed Central

GIRLOVANU, MIHAI; SUSMAN, SERGIU; SORITAU, OLGA; RUS-CIUCA, DAN; MELINCOVICI, CARMEN; CONSTANTIN, ANNE-MARIE; MIHU, CARMEN MIHAELA

2015-01-01

In recent years, the advances in stem cell research have suggested that the human body may have a higher plasticity than it was originally expected. Until now, four categories of stem cells were isolated and cultured in vivo: embryonic stem cells, fetal stem cells, adult stem cells and induced pluripotent stem cells (hiPSCs). Although multiple studies were published, several issues concerning the stem cells are still debated, such as: the molecular mechanisms of differentiation, the methods to prevent teratoma formation or the ethical and religious issues regarding especially the embryonic stem cell research. The direct differentiation of stem cells into specialized cells: cardiac myocytes, neural cells, pancreatic islets cells, may represent an option in treating incurable diseases such as: neurodegenerative diseases, type I diabetes, hematologic or cardiac diseases. Nevertheless, stem cell-based therapies, based on stem cell transplantation, remain mainly at the experimental stages and their major limitation is the development of teratoma and cancer after transplantation. The induced pluripotent stem cells (hiPSCs) represent a prime candidate for future cell therapy research because of their significant self-renewal and differentiation potential and the lack of ethical issues. This article presents an overview of the biological advances in the study of stem cells and the current progress made in the field of regenerative medicine. PMID:26609255

Laser biomodulation on stem cells

NASA Astrophysics Data System (ADS)

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

2001-08-01

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

Pluripotent stem cells.

PubMed

Verfaillie, C

2009-05-01

The isolation of human embryonic stem cells (ESC) in 1998 has created the hope that stem cells will one day be used to regenerate tissues and organs, even though it is obvious that a number of hurdles will need to be overcome for such therapies to become reality. The cloning of "Dolly" in 1997, more than 40 years after the first frogs were cloned, combined with the very fast progress made in our understanding of the molecular processes that govern the pluripotency of ESC has lead to the ability of scientists to recreate a pluripotent state in fibroblasts and other cells from mouse, rat and man, named induced pluripotent stem cells (iPSC). This feat makes it theoretically possible to create patient specific pluripotent stem cells whose differentiated progeny could be used in an autologous manner obviating the need for immunosuppression that would be needed to use allogeneic ESC-derived differentiated cells. In addition, the ability to generate custom made pluripotent stem cells will no doubt lead to the development of protein or small molecule drugs that can induce differentiation not only of iPSC or ESC to mature tissue cells, but also endogenous tissue stem cells. Moreover, it allows scientists to create models of human diseases and may aid the pharmaceutical industry in testing more rigorously toxicity of drugs for human differentiated cells. Thus, there is little doubt that progress in stem cell biology will change many aspects of medicine as we know it in the next one to two decades.

Formaldehyde and co-exposure with benzene induce compensation of bone marrow and hematopoietic stem/progenitor cells in BALB/c mice during post-exposure period

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

Wei, Chenxi

Formaldehyde (FA) is a human leukemogen. Since there is a latency period between initial FA exposure and the development of leukemia, the subsequent impact of FA on hematopoietic stem or progenitor cells (HSCs/HPCs) in post-exposure stage is crucial for a deep understanding of FA-induced hematotoxicity. BALB/c mice were exposed to 3 mg/m{sup 3} FA for 2 weeks, mimicking occupational exposure, and were monitored for another 7 days post-exposure. Meanwhile, we included benzene (BZ) as a positive control, separately and together with FA because co-exposure occurs frequently. After 7-day recovery, colonies of progenitors for CFU-GM and BFU-E, and nucleated bone marrowmore » cells in FA-exposed mice were comparable to controls, although they were significantly reduced during exposure. Levels of reactive oxygen species (ROS) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in CFU-GM and BFU-E from FA-exposed mice were higher than controls, although the increase in 8-OHdG was not significant. Granulocyte-macrophage colony stimulating factor (GM-CSF) level in the FA group was lower than controls, but the expression level for the receptor was not upregulated. It suggests that HSCs/HPCs in FA-exposed mice respond to a small amount of GM-CSF and proliferate rapidly, which may cause a possible risk of expansion of abnormal stem/progenitor cell clones. FA co-exposure with BZ was more potent for promoting CFU-GM formation and inducing ROS in BFU-E and 8-OHdG in CFU-GM during the post-exposure period. The compensation of myeloid progenitors with elevated ROS and 8-OHdG may lead to a risk of transforming normal HSCs/HPCs to leukemic stem/progenitor cells. Thus, co-exposure may pose a greater leukemia risk. - Highlights: • Nucleated bone marrow cell count recovered after 7 days post-FA and/or BZ exposure. • CFU-GM showed an increase in colonies and 8-OHdG after 7 days post-FA + BZ exposure. • Levels of ROS in CFU-GM and BFU-E were increased by FA or FA + BZ during recovery. �

Stem cells and bone diseases: new tools, new perspective

PubMed Central

Riminucci, Mara; Remoli, Cristina; Robey, Pamela G.; Bianco, Paolo

2017-01-01

Postnatal skeletal stem cells are a unique class of progenitors with biological properties that extend well beyond the limits of stemness as commonly defined. Skeletal stem cells sustain skeletal tissue homeostasis, organize and maintain the complex architectural structure of the bone marrow microenvironment and provide a niche for hematopoietic progenitor cells. The identification of stem cells in the human post-natal skeleton has profoundly changed our approach to the physiology and pathology of this system. Skeletal diseases have been long interpreted essentially in terms of defective function of differentiated cells and/or abnormal turnover of the matrix they produce. The notion of a skeletal stem cell has brought forth multiple, novel concepts in skeletal biology that provide potential alternative concepts. At the same time, the recognition of the complex functions played by skeletal progenitors, such as the structural and functional organization of the bone marrow, has provided an innovative, unifying perspective for understanding bone and bone marrow changes simultaneously occurring in many disorders. Finally, the possibility to isolate and highly enrich for skeletal progenitors, enables us to reproduce perfectly normal or pathological organ miniatures. These, in turn, provide suitable models to investigate and manipulate the pathogenetic mechanisms of many genetic and non-genetic skeletal diseases. PMID:25240458

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

PubMed

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

2016-05-01

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

Induced pluripotent stem (iPS) cells from human fetal stem cells.

PubMed

Guillot, Pascale V

2016-02-01

Pluripotency defines the ability of stem cells to differentiate into all the lineages of the three germ layers and self-renew indefinitely. Somatic cells can regain the developmental potential of embryonic stem cells following ectopic expression of a set of transcription factors or, in certain circumstances, via modulation of culture conditions and supplementation with small molecule, that is, induced pluripotent stem (iPS) cells. Here, we discuss the use of fetal tissues for reprogramming, focusing in particular on stem cells derived from human amniotic fluid, and the development of chemical reprogramming. We next address the advantages and disadvantages of deriving pluripotent cells from fetal tissues and the potential clinical applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

Interleukin 6 inhibits the differentiation of rat stem Leydig cells.

PubMed

Wang, Yiyan; Chen, Lanlan; Xie, Lubin; Li, Linchao; Li, Xiaoheng; Li, Huitao; Liu, Jianpeng; Chen, Xianwu; Mao, Baiping; Song, Tiantian; Lian, Qingquan; Ge, Ren-Shan

2018-09-05

Inflammation causes male hypogonadism. Several inflammatory cytokines, including interleukin 6 (IL-6), are released into the blood and may suppress Leydig cell development. The objective of the present study was to investigate whether IL-6 affected the proliferation and differentiation of rat stem Leydig cells. Leydig cell-depleted rat testis (in vivo) and seminiferous tubules (in vitro) with ethane dimethane sulfonate (EDS) were used to explore the effects of IL-6 on stem Leydig cell development. Intratesticular injection of IL-6 (10 and 100 ng/testis) from post-EDS day 14 to 28 blocked the regeneration of Leydig cells, as shown by the lower serum testosterone levels (21.6% of the control at 100 ng/testis dose), the down-regulated Leydig cell gene (Lhcgr, Star, Cyp11a1, Cyp17a1, and Hsd17b3) expressions, and the reduced Leydig cell number. Stem Leydig cells on the surface of the seminiferous tubules were induced to enter the Leydig cell lineage in vitro in the medium containing luteinizing hormone and lithium. IL-6 (1, 10, and 100 ng/ml) concentration-dependently decreased testosterone production and Lhcgr, Cyp11a1, Cyp17a1, Hsd17b3 and Insl3 mRNA levels. The IL-6 mediated effects were antagonized by Janus kinase 1 (JAK) inhibitor (filgotinib) and Signal Transducers and Activators of Transcription 3 (STAT3) inhibitor (S3I-201), indicating that a JAK-STAT3 signaling pathway is involved. In conclusion, our results demonstrated that IL-6 was an inhibitory factor of stem Leydig cell development. Copyright © 2017. Published by Elsevier B.V.

Stem cell clinics online: the direct-to-consumer portrayal of stem cell medicine.

PubMed

Lau, Darren; Ogbogu, Ubaka; Taylor, Benjamin; Stafinski, Tania; Menon, Devidas; Caulfield, Timothy

2008-12-04

Despite the immature state of stem cell medicine, patients are seeking and accessing putative stem cell therapies in an "early market" in which direct-to-consumer advertising via the internet likely plays an important role. We analyzed stem cell clinic websites and appraised the relevant published clinical evidence of stem cell therapies to address three questions about the direct-to-consumer portrayal of stem cell medicine in this early market: What sorts of therapies are being offered? How are they portrayed? Is there clinical evidence to support the use of these therapies? We found that the portrayal of stem cell medicine on provider websites is optimistic and unsubstantiated by peer-reviewed literature.

[Progress in epidermal stem cells].

PubMed

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

2010-03-01

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

Stem cells in kidney regeneration.

PubMed

Yokote, Shinya; Yokoo, Takashi

2012-01-01

Currently many efforts are being made to apply regenerative medicine to kidney diseases using several types of stem/progenitor cells, such as mesenchymal stem cells, renal stem/progenitor cells, embryonic stem cells and induced pluripotent stem cells. Stem cells have the ability to repair injured organs and ameliorate damaged function. The strategy for kidney tissue repair is the recruitment of stem cells and soluble reparative factors to the kidney to elicit tissue repair and the induction of dedifferentiation of resident renal cells. On the other hand, where renal structure is totally disrupted, absolute kidney organ regeneration is needed to rebuild a whole functional kidney. In this review, we describe current advances in stem cell research for kidney tissue repair and de novo organ regeneration.

Fish Stem Cell Cultures

PubMed Central

Hong, Ni; Li, Zhendong; Hong, Yunhan

2011-01-01

Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES) cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on “Fish Stem Cells and Nuclear Transfer”, we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer. PMID:21547056

Fish stem cell cultures.

PubMed

Hong, Ni; Li, Zhendong; Hong, Yunhan

2011-04-13

Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES) cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on "Fish Stem Cells and Nuclear Transfer", we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

Arrhythmia in Stem Cell Transplantation

PubMed Central

Almeida, Shone O.; Skelton, Rhys J.; Adigopula, Sasikanth; Ardehali, Reza

2015-01-01

Synopsis Stem cell regenerative therapies hold promise for treating diseases across the spectrum of medicine. Recent clinical trials have confirmed the safety of stem cell delivery to the heart with promising but variable results. While significant progress has been made in the preclinical stages, the clinical application of cardiac cell therapy is limited by technical challenges, including inability to isolate a pure population of cardiac-specific progenitors capable of robust engraftment and regeneration, lack of appropriate pre-clinical animal models, uncertainty about the best mode of delivery, paucity of adequate imaging modalities, and lack of knowledge about the fate of transplanted cells. The inability of transplanted cells to structurally and functionally integrate into the host myocardium may pose arrhythmogenic risk to patients. This is in part dependent on the type of cell transplanted, where the expression of gap junctions such as connexin-43 is essential not only for electromechanical integration, but has also been found to be protective against electrical instability post-transplant. Additionally, certain methods of cell delivery, such as intramyocardial injection, carry a higher rate of arrhythmias. Other potential contributors to the arrhythmogenicity of cell transplantation include re-entrant pathways due to heterogeneity in conduction velocities between graft and host as well as graft automaticity. In this paper, we discuss the arrhythmogenic potential of cell delivery to the heart. PMID:26002399

[Survival of bone marrow mesenchymal stem cells and periodontal ligament stem cells in cell sheets].

PubMed

An, Kangkang; Liu, Hongwei

2014-11-01

To evaluate the survival of bone marrow mesenchymal stem cells (BMMSC) and periodontal ligament stem cells (PDLSC) in BMMSC/PDLSC cell sheets which transplanted ectopically into subcutaneous dorsum of nude mice. The canine BMMSC and PDLSC from primary culture were tranfected with lentiviral vectors carrying green fluorescent protein (GFP) gene (Lentivirus-GFP) or red fluorescent protein (RFP) gene (Lentivirus-RFP) respectively. The immunophenotypes of GFP-labeled BMMSC and RFP-labeled PDLSC were identified by flow cytometry. Adipogenic and osteogenic differentiation of them were detected by alizarin red or oil red O respectively. Then, both GFP-labeled BMMSC cell sheets and RFP-labeled PDLSC cell sheets were fabricated respectively using normal culture dish (6 cm) after stimulation of extracellular matrix formation. Each was enveloped by collagen membrane (Bio-Gide) and then transplanted into the subcutaneous dorsum of nude mice. In vivo non-invasive biofluorescence imaging(BFI) was performed at 1, 2, 4 and 8 w post-tranplantation to trace and quantify the survival and growth of RFP-labeled PDLSC and GFP-labeled BMMSC via the BFI system of the NightOWL. The fluorescence intensity change of GFP/RFP signal was monitored and compared. The mice were sacrificed 8 weeks after cell sheets transplantation and the survival of stem cells was verified by fluorescence immunohistochemistry. The flow cytometry showed that GFP-labeled BMMSC positively expressed CD29, CD44, CD34, STRO-1 were 93.07%, 92.84%, 3.23%, 67.67%, and RFP-labeled PDLSCs were 89.91%, 88.47%, 6.04%, 74.11%, respectively. Both of them had the potency of differentiating into osteoblasts and adipocytes. The stemness of both of them was almost same. After being transplanted into nude mice, the signal strength of GFP(BMMSC) was weaker and weaker in 1, 2, 4 and 8 w [(83.1±3.1)×10(6), (65.1±2.3)×10(6), (51.5 ± 2.3)×10(6), (33.8 ± 2.0)×10(6) ph/s, respectively.]. The signal strength of RFP(PDLSC) was

Multipotent Stem Cell and Reproduction.

PubMed

Khanlarkhani, Neda; Baazm, Maryam; Mohammadzadeh, Farzaneh; Najafi, Atefeh; Mehdinejadiani, Shayesteh; Sobhani, Aligholi

Stem cells are self-renewing and undifferentiated cell types that can be differentiate into functional cells. Stem cells can be classified into two main types based on their source of origin: Embryonic and Adult stem cells. Stem cells also classified based on the range of differentiation potentials into Totipotent, Pluripotent, Multipotent, and Unipotent. Multipotent stem cells have the ability to differentiate into all cell types within one particular lineage. There are plentiful advantages and usages for multipotent stem cells. Multipotent Stem cells act as a significant key in procedure of development, tissue repair, and protection. The accessibility and adaptability of these amazing cells create them a great therapeutic choice for different part of medical approaches, and it becomes interesting topic in the scientific researches to found obvious method for the most advantageous use of MSC-based therapies. Recent studies in the field of stem cell biology have provided new perspectives and opportunities for the treatment of infertility disorders.

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

PubMed

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

2014-04-26

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

Autophagy in stem cells

PubMed Central

Guan, Jun-Lin; Simon, Anna Katharina; Prescott, Mark; Menendez, Javier A.; Liu, Fei; Wang, Fen; Wang, Chenran; Wolvetang, Ernst; Vazquez-Martin, Alejandro; Zhang, Jue

2013-01-01

Autophagy is a highly conserved cellular process by which cytoplasmic components are sequestered in autophagosomes and delivered to lysosomes for degradation. As a major intracellular degradation and recycling pathway, autophagy is crucial for maintaining cellular homeostasis as well as remodeling during normal development, and dysfunctions in autophagy have been associated with a variety of pathologies including cancer, inflammatory bowel disease and neurodegenerative disease. Stem cells are unique in their ability to self-renew and differentiate into various cells in the body, which are important in development, tissue renewal and a range of disease processes. Therefore, it is predicted that autophagy would be crucial for the quality control mechanisms and maintenance of cellular homeostasis in various stem cells given their relatively long life in the organisms. In contrast to the extensive body of knowledge available for somatic cells, the role of autophagy in the maintenance and function of stem cells is only beginning to be revealed as a result of recent studies. Here we provide a comprehensive review of the current understanding of the mechanisms and regulation of autophagy in embryonic stem cells, several tissue stem cells (particularly hematopoietic stem cells), as well as a number of cancer stem cells. We discuss how recent studies of different knockout mice models have defined the roles of various autophagy genes and related pathways in the regulation of the maintenance, expansion and differentiation of various stem cells. We also highlight the many unanswered questions that will help to drive further research at the intersection of autophagy and stem cell biology in the near future. PMID:23486312

Engineering nanoscale stem cell niche: direct stem cell behavior at cell-matrix interface.

PubMed

Zhang, Yan; Gordon, Andrew; Qian, Weiyi; Chen, Weiqiang

2015-09-16

Biophysical cues on the extracellular matrix (ECM) have proven to be significant regulators of stem cell behavior and evolution. Understanding the interplay of these cells and their extracellular microenvironment is critical to future tissue engineering and regenerative medicine, both of which require a means of controlled differentiation. Research suggests that nanotopography, which mimics the local, nanoscale, topographic cues within the stem cell niche, could be a way to achieve large-scale proliferation and control of stem cells in vitro. This Progress Report reviews the history and contemporary advancements of this technology, and pays special attention to nanotopographic fabrication methods and the effect of different nanoscale patterns on stem cell response. Finally, it outlines potential intracellular mechanisms behind this response. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Biochemistry of epidermal stem cells.

PubMed

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

2013-02-01

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

Drosophila's contribution to stem cell research.

PubMed

Singh, Gyanesh

2015-01-01

The discovery of Drosophila stem cells with striking similarities to mammalian stem cells has brought new hope for stem cell research. Recent developments in Drosophila stem cell research is bringing wider opportunities for contemporary stem cell biologists. In this regard, Drosophila germ cells are becoming a popular model of stem cell research. In several cases, genes that controlled Drosophila stem cells were later discovered to have functional homologs in mammalian stem cells. Like mammals, Drosophila germline stem cells (GSCs) are controlled by both intrinsic as well as external signals. Inside the Drosophila testes, germline and somatic stem cells form a cluster of cells (the hub). Hub cells depend on JAK-STAT signaling, and, in absence of this signal, they do not self-renew. In Drosophila, significant changes occur within the stem cell niche that contributes to a decline in stem cell number over time. In case of aging Drosophila, somatic niche cells show reduced DE-cadherin and unpaired (Upd) proteins. Unpaired proteins are known to directly decrease stem cell number within the niches, and, overexpression of upd within niche cells restored GSCs in older males also . Stem cells in the midgut of Drosophila are also very promising. Reduced Notch signaling was found to increase the number of midgut progenitor cells. On the other hand, activation of the Notch pathway decreased proliferation of these cells. Further research in this area should lead to the discovery of additional factors that regulate stem and progenitor cells in Drosophila.

Molecular imaging in stem cell-based therapies of cardiac diseases.

PubMed

Li, Xiang; Hacker, Marcus

2017-10-01

In the past 15years, despite that regenerative medicine has shown great potential for cardiovascular diseases, the outcome and safety of stem cell transplantation has shown controversial results in the published literature. Medical imaging might be useful for monitoring and quantifying transplanted cells within the heart and to serially characterize the effects of stem cell therapy of the myocardium. From the multiple available noninvasive imaging techniques, magnetic resonance imaging and nuclear imaging by positron (PET) or single photon emission computer tomography (SPECT) are the most used clinical approaches to follow the fate of transplanted stem cells in vivo. In this article, we provide a review on the role of different noninvasive imaging modalities and discuss their advantages and disadvantages. We focus on the different in-vivo labeling and reporter gene imaging strategies for stem cell tracking as well as the concept and reliability to use imaging parameters as noninvasive surrogate endpoints for the evaluation of the post-therapeutic outcome. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of Amniotic Stem Cells

PubMed Central

Koike, Chika; Zhou, Kaixuan; Takeda, Yuji; Fathy, Moustafa; Okabe, Motonori; Yoshida, Toshiko; Nakamura, Yukio; Kato, Yukio

2014-01-01

Abstract The amnion membrane is developed from embryo-derived cells, and amniotic cells have been shown to exhibit multidifferentiation potential. These cells represent a desirable source for stem cells for a variety of reasons. However, to date very few molecular analyses of amnion-derived cells have been reported, and efficient markers for isolating the stem cells remain unclear. This paper assesses the characterization of amnion-derived cells as stem cells by examining stemness marker expressions for amnion-derived epithelial cells and mesenchymal cells by flow cytometry, immunocytochemistry, and quantitative PCR. Flow cytometry revealed that amnion epithelial cells expressed CD133, CD 271, and TRA-1-60, whereas mecenchymal cells expressed CD44, CD73, CD90, and CD105. Immunohistochemistry showed that both cells expressed the stemness markers Oct3/4, Sox2, Klf4, and SSEA4. Stemness genes' expression in amnion epithelial cells, mesenchymal cells, fibroblast, bone marrow–derived mesenchymal stem cells (MSCs), and induced pluripotent stem cells (iPSCs) was compared by quantitative reverse-transcription polymerase chain reaction (RT-PCR). Amnion-derived epithelial cells and mesenchymal cells expressed Oct3/4, Nanog, and Klf4 more than bone marrow–derived MSCs. The sorted TRA1-60–positive cells expressed Oct3/4, Nanog, and Klf4 more than unsorted cells or TRA1-60–negative cells. TRA1-60 can be a marker for isolating amnion epithelial stem cells. PMID:25068631

SPECIFICITIES OF ENDOMETRIAL PROLIFERATION/STEM CELL INDEX DISTRIBUTION IN ENDOMETRIOID CARCINOMA OF DIFFERENT GRADE OF MALIGNANCY.

PubMed

Kikalishvili, N; Beriashvili, R; Muzashvili, T; Burkadze, G

2018-03-01

.1) reproductive age - 22.4; 1.2) menopause - 23.5; 1.3) post-menopause - 24.8. Proliferative/stem cell index reaches its maximum in the samples retrieved from post-menopause age, and decreases significantly in reproductive age individuals. In the 2nd study group labeled as "Endometrioid Carcinoma Grade 2", the proliferative/stem cell index increases and ranges within the interval 23.2-27.8. Its mean average value in the age distribution subgroups accounts for: 2.1) reproductive age -23.7; 2.2) menopause - 24.2; 2.3) post-menopause - 25.8. In the 3rd study group labeled as "Endometrioid Carcinoma Grade 3", the proliferative/stem cell index markedly increases and ranges within the interval 25.8-29.4. Its mean average value in the age distribution subgroups accounts for: 3.1) reproductive age - 28.4; 3.2) menopause - 28.5; 3.3) post-menopause - 28.5. It was found that average value of proliferative/stem cell index in the 1st and 2nd study groups (EC Grade 1/2) keeps the same tendencies of increase in age subgroups as well as at endometrial hyperplasia conditions - in particular in both study groups increase in value of the proliferative/stem cell index in age subgroups makes about 1% (1st study group-0,97%, 2nd study group-0,96%). What about 3rd study group (EC Grade 3) average value of proliferative/stem cell index in age subgroups is almost the same. It was found that average value of proliferative/stem cell index in endometrioid carcinoma most markedly differs from the norm in post-menopause period. The study showed that average value of proliferative/stem cell index in endometrioid carcinoma cases (EC Grade 1/2) tends to increase with age like endometrial hyperplasia conditions, in contrast with the norm, where it is observed to progressively decrease with aging. The attention should be given to the fact that the mean average value of proliferative/stem cell index in endometrioid carcinoma Grade 3 is almost constant.

Strategies to improve homing of mesenchymal stem cells for greater efficacy in stem cell therapy.

PubMed

Naderi-Meshkin, Hojjat; Bahrami, Ahmad Reza; Bidkhori, Hamid Reza; Mirahmadi, Mahdi; Ahmadiankia, Naghmeh

2015-01-01

Stem/progenitor cell-based therapeutic approach in clinical practice has been an elusive dream in medical sciences, and improvement of stem cell homing is one of major challenges in cell therapy programs. Stem/progenitor cells have a homing response to injured tissues/organs, mediated by interactions of chemokine receptors expressed on the cells and chemokines secreted by the injured tissue. For improvement of directed homing of the cells, many techniques have been developed either to engineer stem/progenitor cells with higher amount of chemokine receptors (stem cell-based strategies) or to modulate the target tissues to release higher level of the corresponding chemokines (target tissue-based strategies). This review discusses both of these strategies involved in the improvement of stem cell homing focusing on mesenchymal stem cells as most frequent studied model in cellular therapies. © 2014 International Federation for Cell Biology.

Stem cells and female reproduction.

PubMed

Du, Hongling; Taylor, Hugh S

2009-02-01

Several recent findings in stem cell biology have resulted in new opportunities for the treatment of reproductive disease. Endometrial regeneration can be driven by bone marrow derived stem cells. This finding has potential implications for the treatment of uterine disorders. It also supports a new theory for the etiology of endometriosis. The ovaries have been shown to contain stem cells that form oocytes in adults and can be cultured in vitro to develop mature oocytes. Stem cells from the fetus have been demonstrated to lead to microchimerism in the mother and implicated in several maternal diseases. Additionally the placenta may be another source of hematopoietic stem cell. Finally endometrial derived stem cells have been demonstrated to differentiate into non-reproductive tissues. While we are just beginning to understand stem cells and many key questions remain, the potential advantages of stem cells in reproductive biology and medicine are apparent.

Drosophila's contribution to stem cell research

PubMed Central

Singh, Gyanesh

2016-01-01

The discovery of Drosophila stem cells with striking similarities to mammalian stem cells has brought new hope for stem cell research. Recent developments in Drosophila stem cell research is bringing wider opportunities for contemporary stem cell biologists. In this regard, Drosophila germ cells are becoming a popular model of stem cell research. In several cases, genes that controlled Drosophila stem cells were later discovered to have functional homologs in mammalian stem cells. Like mammals, Drosophila germline stem cells (GSCs) are controlled by both intrinsic as well as external signals. Inside the Drosophila testes, germline and somatic stem cells form a cluster of cells (the hub). Hub cells depend on JAK-STAT signaling, and, in absence of this signal, they do not self-renew. In Drosophila, significant changes occur within the stem cell niche that contributes to a decline in stem cell number over time. In case of aging Drosophila, somatic niche cells show reduced DE-cadherin and unpaired (Upd) proteins. Unpaired proteins are known to directly decrease stem cell number within the niches, and, overexpression of upd within niche cells restored GSCs in older males also . Stem cells in the midgut of Drosophila are also very promising. Reduced Notch signaling was found to increase the number of midgut progenitor cells. On the other hand, activation of the Notch pathway decreased proliferation of these cells. Further research in this area should lead to the discovery of additional factors that regulate stem and progenitor cells in Drosophila. PMID:26180635

Are stem cells drugs? The regulation of stem cell research and development.

PubMed

Rosen, Michael R

2006-10-31

Stem cell research and its clinical application have become political, social, and medical lightning rods, polarizing opinion among members of the lay community and among medical/scientific professionals. A potpourri of opinion, near-anecdotal observation, and scientifically sound data has sown confusion in ways rarely seen in the medical arts and sciences. A major issue is regulation, with different aspects of stem cell research falling within the purview of different government agencies and local offices. An overarching clearinghouse to review the field and recommend policy is lacking. In the following pages, I touch on the societal framework for regulation, the known and potential risks and benefits of cardiovascular stem cell therapies, whether stem cells should be regulated as drugs or in analogy to drugs, and if there is to be regulation, then by whom. In so doing, I refer to the stem cell literature only as it relates to the discussion of regulation because this is not a review of stem cell research; it is an opinion regarding regulation.

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

PubMed Central

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

2014-01-01

Multipotent mesenchymal stromal cells (MSC), have the potential to differentiate into cells of the mesenchymal lineage and have non-progenitor functions including immunomodulation. The demonstration that MSCs are perivascular cells found in almost all adult tissues raises fascinating perspectives on their role in tissue maintenance and repair. However, some controversies about the physiological role of the perivascular MSCs residing outside the bone marrow and on their therapeutic potential in regenerative medicine exist. In brain, perivascular MSCs like pericytes and adventitial cells, could constitute another stem cell population distinct to the neural stem cell pool. The demonstration of the neuronal potential of MSCs requires stringent criteria including morphological changes, the demonstration of neural biomarkers expression, electrophysiological recordings, and the absence of cell fusion. The recent finding that brain cancer stem cells can transdifferentiate into pericytes is another facet of the plasticity of these cells. It suggests that the perversion of the stem cell potential of pericytes might play an even unsuspected role in cancer formation and tumor progression. PMID:24772240

Mammary Stem Cells and Breast Cancer Stem Cells: Molecular Connections and Clinical Implications.

PubMed

Celià-Terrassa, Toni

2018-05-04

Cancer arises from subpopulations of transformed cells with high tumor initiation and repopulation ability, known as cancer stem cells (CSCs), which share many similarities with their normal counterparts. In the mammary gland, several studies have shown common molecular regulators between adult mammary stem cells (MaSCs) and breast cancer stem cells (bCSCs). Cell plasticity and self-renewal are essential abilities for MaSCs to maintain tissue homeostasis and regenerate the gland after pregnancy. Intriguingly, these properties are similarly executed in breast cancer stem cells to drive tumor initiation, tumor heterogeneity and recurrence after chemotherapy. In addition, both stem cell phenotypes are strongly influenced by external signals from the microenvironment, immune cells and supportive specific niches. This review focuses on the intrinsic and extrinsic connections of MaSC and bCSCs with clinical implications for breast cancer progression and their possible therapeutic applications.

The neural stem cell fate determinant TLX promotes tumorigenesis and genesis of cells resembling glioma stem cells.

PubMed

Park, Hyo-Jung; Kim, Jun-Kyum; Jeon, Hye-Min; Oh, Se-Yeong; Kim, Sung-Hak; Nam, Do-Hyun; Kim, Hyunggee

2010-11-01

A growing body of evidence indicates that deregulation of stem cell fate determinants is a hallmark of many types of malignancies. The neural stem cell fate determinant TLX plays a pivotal role in neurogenesis in the adult brain by maintaining neural stem cells. Here, we report a tumorigenic role of TLX in brain tumor initiation and progression. Increased TLX expression was observed in a number of glioma cells and glioma stem cells, and correlated with poor survival of patients with gliomas. Ectopic expression of TLX in the U87MG glioma cell line and Ink4a/Arf-deficient mouse astrocytes (Ink4a/Arf(-/-) astrocytes) induced cell proliferation with a concomitant increase in cyclin D expression, and accelerated foci formation in soft agar and tumor formation in in vivo transplantation assays. Furthermore, overexpression of TLX in Ink4a/Arf(-/-) astrocytes inhibited cell migration and invasion and promoted neurosphere formation and Nestin expression, which are hallmark characteristics of glioma stem cells, under stem cell culture conditions. Our results indicate that TLX is involved in glioma stem cell genesis and represents a potential therapeutic target for this type of malignancy.

Engraftment of donor mesenchymal stem cells in chimeric BXSB includes vascular endothelial cells and hepatocytes.

PubMed

Jones, Olcay Y; Gok, Faysal; Rushing, Elisabeth J; Horkayne-Szakaly, Iren; Ahmed, Atif A

2011-01-01

Somatic tissue engraftment was studied in BXSB mice treated with mesenchymal stem cell transplantation. Hosts were conditioned with nonlethal radiation prior to introducing donor cells from major histocompatibility complex-matched green fluorescent protein transgenic mice. Transplant protocols differed for route of injection, ie, intravenous (i.v.) versus intraperitoneal (i.p.), and source of mesenchymal stem cells, ie, unfractionated bone marrow cells, ex vivo expanded mesenchymal stem cells, or bone chips. Tissue chimerism was determined after short (10-12 weeks) or long (62 weeks) posttransplant follow-up by immunohistochemistry for green fluorescent protein. Engraftment of endothelial cells was seen in several organs including liver sinusoidal cells in i.v. treated mice with ex vivo expanded mesenchymal stem cells or with unfractionated bone marrow cells. Periportal engraftment of liver hepatocytes, but not engraftment of endothelial cells, was found in mice injected i.p. with bone chips. Engraftment of adipocytes was a common denominator in both i.v. and i.p. routes and occurred during early phases post-transplant. Disease control was more robust in mice that received both i.v. bone marrow and i.p. bone chips compared to mice that received i.v. bone marrow alone. Thus, the data support potential use of mesenchymal stem cell transplant for treatment of severe lupus. Future studies are needed to optimize transplant conditions and tailor protocols that may in part be guided by fat and endothelial biomarkers. Furthermore, the role of liver chimerism in disease control and the nature of cellular communication among donor hematopoietic and mesenchymal stem cells in a chimeric host merit further investigation.

Cancer stem cells and differentiation therapy.

PubMed

Jin, Xiong; Jin, Xun; Kim, Hyunggee

2017-10-01

Cancer stem cells can generate tumors from only a small number of cells, whereas differentiated cancer cells cannot. The prominent feature of cancer stem cells is its ability to self-renew and differentiate into multiple types of cancer cells. Cancer stem cells have several distinct tumorigenic abilities, including stem cell signal transduction, tumorigenicity, metastasis, and resistance to anticancer drugs, which are regulated by genetic or epigenetic changes. Like normal adult stem cells involved in various developmental processes and tissue homeostasis, cancer stem cells maintain their self-renewal capacity by activating multiple stem cell signaling pathways and inhibiting differentiation signaling pathways during cancer initiation and progression. Recently, many studies have focused on targeting cancer stem cells to eradicate malignancies by regulating stem cell signaling pathways, and products of some of these strategies are in preclinical and clinical trials. In this review, we describe the crucial features of cancer stem cells related to tumor relapse and drug resistance, as well as the new therapeutic strategy to target cancer stem cells named "differentiation therapy."

Materials as stem cell regulators

PubMed Central

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

2014-01-01

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

The Drosophila ovarian and testis stem cell niches: similar somatic stem cells and signals.

PubMed

Decotto, Eva; Spradling, Allan C

2005-10-01

The stem cell niches at the apex of Drosophila ovaries and testes have been viewed as distinct in two major respects. While both contain germline stem cells, the testis niche also contains "cyst progenitor" stem cells, which divide to produce somatic cells that encase developing germ cells. Moreover, while both niches utilize BMP signaling, the testis niche requires a key JAK/STAT signal. We now show, by lineage marking, that the ovarian niche also contains a second type of stem cell. These "escort stem cells" morphologically resemble testis cyst progenitor cells and their daughters encase developing cysts before undergoing apoptosis at the time of follicle formation. In addition, we show that JAK/STAT signaling also plays a critical role in ovarian niche function, and acts within escort cells. These observations reveal striking similarities in the stem cell niches of male and female gonads, and suggest that they are largely governed by common mechanisms.

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.

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.

Fip1 regulates mRNA alternative polyadenylation to promote stem cell self-renewal

PubMed Central

Lackford, Brad; Yao, Chengguo; Charles, Georgette M; Weng, Lingjie; Zheng, Xiaofeng; Choi, Eun-A; Xie, Xiaohui; Wan, Ji; Xing, Yi; Freudenberg, Johannes M; Yang, Pengyi; Jothi, Raja; Hu, Guang; Shi, Yongsheng

2014-01-01

mRNA alternative polyadenylation (APA) plays a critical role in post-transcriptional gene control and is highly regulated during development and disease. However, the regulatory mechanisms and functional consequences of APA remain poorly understood. Here, we show that an mRNA 3′ processing factor, Fip1, is essential for embryonic stem cell (ESC) self-renewal and somatic cell reprogramming. Fip1 promotes stem cell maintenance, in part, by activating the ESC-specific APA profiles to ensure the optimal expression of a specific set of genes, including critical self-renewal factors. Fip1 expression and the Fip1-dependent APA program change during ESC differentiation and are restored to an ESC-like state during somatic reprogramming. Mechanistically, we provide evidence that the specificity of Fip1-mediated APA regulation depends on multiple factors, including Fip1-RNA interactions and the distance between APA sites. Together, our data highlight the role for post-transcriptional control in stem cell self-renewal, provide mechanistic insight on APA regulation in development, and establish an important function for APA in cell fate specification. PMID:24596251

Stem cells in gastroenterology and hepatology

PubMed Central

Quante, Michael; Wang, Timothy C.

2010-01-01

Cellular and tissue regeneration in the gastrointestinal tract and liver depends on stem cells with properties of longevity, self-renewal and multipotency. Progress in stem cell research and the identification of potential esophageal, gastric, intestinal, colonic, hepatic and pancreatic stem cells provides hope for the use of stem cells in regenerative medicine and treatments for disease. Embryonic stem cells and induced pluripotent stem cells have the potential to give rise to any cell type in the human body, but their therapeutic application remains challenging. The use of adult or tissue-restricted stem cells is emerging as another possible approach for the treatment of gastrointestinal diseases. The same self-renewal properties that allow stem cells to remain immortal and generate any tissue can occasionally make their proliferation difficult to control and make them susceptible to malignant transformation. This Review provides an overview of the different types of stem cell, focusing on tissue-restricted adult stem cells in the fields of gastroenterology and hepatology and summarizing the potential benefits and risks of using stems cells to treat gastroenterological and liver disorders. PMID:19884893

Sonic hedgehog-expressing basal cells are general post-mitotic precursors of functional taste receptor cells

PubMed Central

Miura, Hirohito; Scott, Jennifer K.; Harada, Shuitsu; Barlow, Linda A.

2014-01-01

Background Taste buds contain ~60 elongate cells and several basal cells. Elongate cells comprise three functional taste cell types: I - glial cells, II - bitter/sweet/umami receptor cells, and III - sour detectors. Although taste cells are continuously renewed, lineage relationships among cell types are ill-defined. Basal cells have been proposed as taste bud stem cells, a subset of which express Sonic hedgehog (Shh). However, Shh+ basal cells turnover rapidly suggesting that Shh+ cells are precursors of some or all taste cell types. Results To fate map Shh-expressing cells, mice carrying ShhCreERT2 and a high (CAG-CAT-EGFP) or low (R26RLacZ) efficiency reporter allele were given tamoxifen to activate Cre in Shh+ cells. Using R26RLacZ, lineage-labeled cells occur singly within buds, supporting a post-mitotic state for Shh+ cells. Using either reporter, we show that Shh+ cells differentiate into all three taste cell types, in proportions reflecting cell type ratios in taste buds (I > II > III). Conclusions Shh+ cells are not stem cells, but are post-mitotic, immediate precursors of taste cells. Shh+ cells differentiate into each of the three taste cell types, and the choice of a specific taste cell fate is regulated to maintain the proper ratio within buds. PMID:24590958

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.

MiRNA-20 and mirna-106a regulate spermatogonial stem cell renewal at the post-transcriptional level via targeting STAT3 and Ccnd1.

PubMed

He, Zuping; Jiang, Jiji; Kokkinaki, Maria; Tang, Lin; Zeng, Wenxian; Gallicano, Ian; Dobrinski, Ina; Dym, Martin

2013-10-01

Studies on spermatogonial stem cells (SSCs) are of unusual significance because they are the unique stem cells that transmit genetic information to subsequent generations and they can acquire pluripotency to become embryonic stem-like cells that have therapeutic applications in human diseases. MicroRNAs (miRNAs) have recently emerged as critical endogenous regulators in mammalian cells. However, the function and mechanisms of individual miRNAs in regulating SSC fate remain unknown. Here, we report for the first time that miRNA-20 and miRNA-106a are preferentially expressed in mouse SSCs. Functional assays in vitro and in vivo using miRNA mimics and inhibitors reveal that miRNA-20 and miRNA-106a are essential for renewal of SSCs. We further demonstrate that these two miRNAs promote renewal at the post-transcriptional level via targeting STAT3 and Ccnd1 and that knockdown of STAT3, Fos, and Ccnd1 results in renewal of SSCs. This study thus provides novel insights into molecular mechanisms regulating renewal and differentiation of SSCs and may have important implications for regulating male reproduction. © AlphaMed Press.

Neural stem cells induce the formation of their physical niche during organogenesis

PubMed Central

Riebesehl, Bea F; Ambrosio, Elizabeth M; Stolper, Julian S; Lischik, Colin Q; Dross, Nicolas

2017-01-01

Most organs rely on stem cells to maintain homeostasis during post-embryonic life. Typically, stem cells of independent lineages work coordinately within mature organs to ensure proper ratios of cell types. Little is known, however, on how these different stem cells locate to forming organs during development. Here we show that neuromasts of the posterior lateral line in medaka are composed of two independent life-long lineages with different embryonic origins. Clonal analysis and 4D imaging revealed a hierarchical organisation with instructing and responding roles: an inner, neural lineage induces the formation of an outer, border cell lineage (nBC) from the skin epithelium. Our results demonstrate that the neural lineage is necessary and sufficient to generate nBCs highlighting self-organisation principles at the level of the entire embryo. We hypothesise that induction of surrounding tissues plays a major role during the establishment of vertebrate stem cell niches. PMID:28950935

Ovarian Stem Cells-the Pros and Cons.

PubMed

Evron, Ayelet; Blumenfeld, Zeev

2013-03-20

The potential for postnatal de novo oogenesis in mammals and in humans has become very controversial in the fields of reproductive science and biology. Historically, it has been thought that females of most mammalian species lose the ability to produce oocytes at birth. A contemporary understanding of stem cell biology together with novel experimental methods has challenged the model of a prenatal fixed ovarian primordial follicle pool that declines with age. Researchers have suggested replenishment of post-natal oocytes by germ-line stem cells (GSCs). According to this theory, GSCs produce oocytes and primordial follicles throughout the lifetime of the adult female. This review describes recent approaches supporting the revolutionary idea of de novo oogenesis in mammals and humans of reproductive-age and provides counter arguments from opponents of this novel and innovative concept.

When stem cells grow old: phenotypes and mechanisms of stem cell aging

PubMed Central

Schultz, Michael B.; Sinclair, David A.

2016-01-01

All multicellular organisms undergo a decline in tissue and organ function as they age. An attractive theory is that a loss in stem cell number and/or activity over time causes this decline. In accordance with this theory, aging phenotypes have been described for stem cells of multiple tissues, including those of the hematopoietic system, intestine, muscle, brain, skin and germline. Here, we discuss recent advances in our understanding of why adult stem cells age and how this aging impacts diseases and lifespan. With this increased understanding, it is feasible to design and test interventions that delay stem cell aging and improve both health and lifespan. PMID:26732838

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.

Infused autograft lymphocyte-to-monocyte ratio and survival in T-cell lymphoma post-autologous peripheral blood hematopoietic stem cell transplantation.

PubMed

Porrata, Luis F; Inwards, David J; Ansell, Stephen M; Micallef, Ivana N; Johnston, Patrick B; Hogan, William J; Markovic, Svetomir N

2015-07-03

The infused autograft lymphocyte-to-monocyte ratio (A-LMR) is a prognostic factor for survival in B-cell lymphomas post-autologous peripheral hematopoietic stem cell transplantation (APHSCT). Thus, we set out to investigate if the A-LMR is also a prognostic factor for survival post-APHSCT in T-cell lymphomas. From 1998 to 2014, 109 T-cell lymphoma patients that underwent APHSCT were studied. Receiver operating characteristic (ROC) and area under the curve (AUC) were used to identify the optimal cut-off value of A-LMR for survival analysis and k-fold cross-validation model to validate the A-LMR cut-off value. Univariate and multivariate Cox proportional hazard models were used to assess the prognostic discriminator power of A-LMR. ROC and AUC identified an A-LMR ≥ 1 as the best cut-off value and was validated by k-fold cross-validation. Multivariate analysis showed A-LMR to be an independent prognostic factor for overall survival (OS) and progression-free survival (PFS). Patients with an A-LMR ≥ 1.0 experienced a superior OS and PFS versus patients with an A-LMR < 1.0 [median OS was not reached vs 17.9 months, 5-year OS rates of 87% (95% confidence interval (CI), 75-94%) vs 26% (95% CI, 13-42%), p < 0.0001; median PFS was not reached vs 11.9 months, 5-year PFS rates of 72% (95% CI, 58-83%) vs 16% (95% CI, 6-32%), p < 0.0001]. A-LMR is also a prognostic factor for clinical outcomes in patients with T-cell lymphomas undergoing APHSCT.

Information on Stem Cell Research

MedlinePlus

... of stem cells share similar properties there are differences as well. For example, ES cells and iPS cells are able to differentiate into any type of cell, whereas adult stem cells are more restricted in their potential. The promise of all stem cells for use ...

Cryptococcus laurentii diarrhea post hematopoietic stem cell transplant.

PubMed

Bhat, Vivek; Vira, Hemant; Khattry, Navin; Toshniwal, Manoj

2017-04-01

We report the recent isolation of Cryptococcus laurentii from the feces of a patient with Hodgkin's lymphoma who underwent autologous hematopoietic stem cell transplant (HSCT). The organism was identified using microscopic morphology, cultural characteristics, and biochemical tests including sugar assimilation. Minimum inhibitory concentration of various antifungals was determined by microbroth dilution method. The recovery of pure culture of C. laurentii from stool culture, and the patient's response to treatment with voriconazole support its potential etiological role. To the best of our knowledge, we report the first case of diarrhea caused by C. laurentii in an HSCT recipient. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

A novel autologous stem cell procedure for the treatment of aplastic anaemia using reprogrammed mature adult cells: a pilot study

PubMed Central

Abuljadayel, Ilham Saleh; Mohanty, Dipika; Suri, Rajendar K.

2012-01-01

Background & objectives: Aplastic anaemia is a life threatening rare bone marrow failure disorder. The underlying haematopoietic cellular deficit leads to haemorrhage, infection and severe anaemia. The treatment of choice for this haematological condition is allogeneic bone marrow transplantation from fully matched HLA sibling. Though this procedure is curative in the majority of young patients with aplastic anaemia, extending this benefit to older patients or those lacking a family donor remains a major challenge. Herein, the safety and efficacy of infusing autologous retrodifferentiated haematopoietic stem cells (RHSC) into four patients with aplastic anaemia without the use of any pre- or post-conditioning regimen including immunosuppression is described. Methods: Un-mobilized, mononuclear cells were harvested from four patients with acquired aplastic anaemia by aphaeresis. Mononuclear cells of patients were cultured with purified monoclonal antibody against the monomorphic regions of the beta chain of MHC class II antigens (Clone CR3/43) for 3 h, to obtain autologous RHSC. Autologous RHSC were washed and infused into the four patients without the use of any pre- or post-conditioning regimen. Thereafter, the efficacy (engraftment) of autologous RHSC was assessed in these patients. Results: Following single infusion of the autologous RHSC, two of the four patients with aplastic anaemia become transfusion independent for more than seven years. Karyotyping and G-banding analysis prior and post-procedure in all patients remained the same. Interpretation & conclusions: The findings of this pilot study demonstrated the functional utility of reprogrammed fully differentiated adult cells into pluripotent stem cells with extensive repopulation potentials in a human setting and without any pre- or post-conditioning regimen, including immunosuppression. This autologous approach of stem cell creation may broaden the curative potentials of stem cell therapy to a wider

A novel autologous stem cell procedure for the treatment of aplastic anaemia using reprogrammed mature adult cells: a pilot study.

PubMed

Abuljadayel, Ilham Saleh; Mohanty, Dipika; Suri, Rajendar K

2012-06-01

Aplastic anaemia is a life threatening rare bone marrow failure disorder. The underlying haematopoietic cellular deficit leads to haemorrhage, infection and severe anaemia. The treatment of choice for this haematological condition is allogeneic bone marrow transplantation from fully matched HLA sibling. Though this procedure is curative in the majority of young patients with aplastic anaemia, extending this benefit to older patients or those lacking a family donor remains a major challenge. Herein, the safety and efficacy of infusing autologous retrodifferentiated haematopoietic stem cells (RHSC) into four patients with aplastic anaemia without the use of any pre- or post-conditioning regimen including immunosuppression is described. Un-mobilized, mononuclear cells were harvested from four patients with acquired aplastic anaemia by aphaeresis. Mononuclear cells of patients were cultured with purified monoclonal antibody against the monomorphic regions of the beta chain of MHC class II antigens (Clone CR3/43) for 3 h, to obtain autologous RHSC. Autologous RHSC were washed and infused into the four patients without the use of any pre- or post-conditioning regimen. Thereafter, the efficacy (engraftment) of autologous RHSC was assessed in these patients. Following single infusion of the autologous RHSC, two of the four patients with aplastic anaemia become transfusion independent for more than seven years. Karyotyping and G-banding analysis prior and post-procedure in all patients remained the same. The findings of this pilot study demonstrated the functional utility of reprogrammed fully differentiated adult cells into pluripotent stem cells with extensive repopulation potentials in a human setting and without any pre- or post-conditioning regimen, including immunosuppression. This autologous approach of stem cell creation may broaden the curative potentials of stem cell therapy to a wider population of patients with aplastic anaemia, including many patients suffering

Adipose-derived stem cell: a better stem cell than BMSC.

PubMed

Zhu, Yanxia; Liu, Tianqing; Song, Kedong; Fan, Xiubo; Ma, Xuehu; Cui, Zhanfeng

2008-08-01

To further study the proliferation and multi-differentiation potentials of adipose-derived stem cells (ADSCs), the cells were isolated with improved methods and their growth curves were achieved with cck-8. Surface protein expression was analyzed by flow cytometry to characterize the cell phenotype. The multi-lineage potential of ADSCs was testified by differentiating cells with adipogenic, chondrogenic, osteogenic, and myogenic inducers. The results showed that about 5 x 10(5) stem cells could be obtained from 400 to 600 mg adipose tissue. The ADSCs can be continuously cultured in vitro for up to 1 month without passage and they have several logarithmic growth phases during the culture period. Also, the flow cytometry analysis showed that ADSCs expressed high levels of stem cell-related antigens (CD13, CD29, CD44, CD105, and CD166), while did not express hematopoiesis-related antigens CD34 and CD45, and human leukocyte antigen HLA-DR was also negative. Moreover, stem cell-related transcription factors, Nanog, Oct-4, Sox-2, and Rex-1 were positively expressed in ADSCs. The expression of alkaline phosphatase (ALP) was detected in the early osteogenic induction and the calcified nodules were observed by von Kossa staining. Intracellular lipid droplets could be observed by Oil Red staining. Differentiated cardiomyocytes were observed by connexin43 fluorescent staining. In order to obtain more stem cells, we can subculture ADSCs every 14 days instead of the normal 5 days. ADSCs still keep strong proliferation ability, maintain their phenotypes, and have stronger multi-differentiation potential after 25 passages. Copyright 2008 John Wiley & Sons, Ltd.

Stem Cells and Aging.

PubMed

Koliakos, George

2017-02-01

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

Presence of stem/progenitor cells in the rat penis.

PubMed

Lin, Guiting; Alwaal, Amjad; Zhang, Xiaoyu; Wang, Jianwen; Wang, Lin; Li, Huixi; Wang, Guifang; Ning, Hongxiu; Lin, Ching-Shwun; Xin, Zhongcheng; Lue, Tom F

2015-01-15

Tissue resident stem cells are believed to exist in every organ, and their identification is commonly done using a combination of immunostaining for putative stem cell markers and label-retaining cell (LRC) strategy. In this study, we employed these approaches to identify potential stem cells in the penis. Newborn rats were intraperitoneally injected with thymidine analog, 5-ethynyl-2-deoxyuridine (EdU), and their penis was harvested at 7 h, 3 days, 1 week, and 4 weeks. It was processed for EdU stains and immunofluorescence staining for stem cell markers A2B5, PCNA, and c-kit. EdU-positive cells were counted for each time point and co-localized with each stem cell marker, then isolated and cultured in vitro followed by their characterization using flowcytometry and immunofluorescence. At 7 h post-EdU injection, 410 ± 105.3 penile corporal cells were labeled in each cross-section (∼28%). The number of EdU-positive cells at 3 days increased to 536 ± 115.6, while their percentage dropped to 25%. Progressively fewer EdU-positive cells were present in the sacrificed rat penis at longer time points (1 and 4 weeks). They were mainly distributed in the subtunic and perisinusoidal spaces, and defined as subtunic penile progenitor cells (STPCs) and perisinusoidal penile progenitor cells (PPCs). These cells expressed c-kit, A2B5, and PCNA. After culturing in vitro, only ∼0.324% corporal cells were EdU-labeled LRCs and expressed A2B5/PCNA. Therefore, labeling of penis cells by EdU occurred randomly, and label retaining was not associated with expression of c-kit, A2B5, or PCNA. The penile LRCs are mainly distributed within the subtunic and perisinusoidal space.

Neural Stem Cell or Human Induced Pluripotent Stem Cell-derived GABA-ergic Progenitor Cell Grafting in an Animal Model of Chronic Temporal Lobe Epilepsy

PubMed Central

Upadhya, Dinesh; Hattiangady, Bharathi; Shetty, Geetha A.; Zanirati, Gabriele; Kodali, Maheedhar; Shetty, Ashok K.

2016-01-01

Grafting of neural stem cells (NSCs) or GABA-ergic progenitor cells (GPCs) into the hippocampus could offer an alternative therapy to hippocampal resection in patients with drug-resistant chronic epilepsy, which afflicts >30% of temporal lobe epilepsy (TLE) cases. Multipotent, self-renewing NSCs could be expanded from multiple regions of the developing and adult brain, human embryonic stem cells (hESCs), and human induced pluripotent stem cells (hiPSCs). On the other hand, GPCs could be generated from the medial and lateral ganglionic eminences of the embryonic brain and from hESCs and hiPSCs. To provide comprehensive methodologies involved in testing the efficacy of transplantation of NSCs and GPCs in a rat model of chronic TLE, NSCs derived from the rat medial ganglionic eminence (MGE) and MGE-like GPCs derived from hiPSCs are taken as examples in this unit. The topics comprise description of the required materials, reagents and equipment, methods for obtaining rat MGE-NSCs and hiPSC-derived MGE-like GPCs in culture, generation of chronically epileptic rats, intrahippocampal grafting procedure, post-grafting evaluation of the effects of grafts on spontaneous recurrent seizures and cognitive and mood impairments, analyses of the yield and the fate of graft-derived cells, and the effects of grafts on the host hippocampus. PMID:27532817

Infectious complications after hematopoietic stem cell transplantation: current status and future perspectives in Korea

PubMed Central

Cho, Sung-Yeon; Lee, Hyeon-Jeong; Lee, Dong-Gun

2018-01-01

Hematopoietic stem cell transplantation (HSCT) is a treatment for hematologic malignancies, immune deficiencies, or genetic diseases, ect. Recently, the number of HSCTs performed in Korea has increased and the outcomes have improved. However, infectious complications account for most of the morbidity and mortality after HSCT. Post-HSCT infectious complications are usually classified according to the time after HSCT: pre-engraftment, immediate post-engraftment, and late post-engraftment period. In addition, the types and risk factors of infectious complications differ according to the stem cell source, donor type, conditioning intensity, region, prophylaxis strategy, and comorbidities, such as graft-versushost disease and invasive fungal infection. In this review, we summarize infectious complications after HSCT, focusing on the Korean perspectives. PMID:29506345

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.

Stem Cells in Mammalian Gonads.

PubMed

Wu, Ji; Ding, Xinbao; Wang, Jian

Stem cells have great value in clinical application because of their ability to self-renew and their potential to differentiate into many different cell types. Mammalian gonads, including testes for males and ovaries for females, are composed of germline and somatic cells. In male mammals, spermatogonial stem cells maintain spermatogenesis which occurs continuously in adult testis. Likewise, a growing body of evidence demonstrated that female germline stem cells could be found in mammalian ovaries. Meanwhile, prior studies have shown that somatic stem cells exist in both testes and ovaries. In this chapter, we focus on mammalian gonad stem cells and discuss their characteristics as well as differentiation potentials.

Neurotrophin Signaling and Stem Cells-Implications for Neurodegenerative Diseases and Stem Cell Therapy.

PubMed

Pramanik, Subrata; Sulistio, Yanuar Alan; Heese, Klaus

2017-11-01

Neurotrophins (NTs) are members of a neuronal growth factor protein family whose action is mediated by the tropomyosin receptor kinase (TRK) receptor family receptors and the p75 NT receptor (p75NTR), a member of the tumor necrosis factor (TNF) receptor family. Although NTs were first discovered in neurons, recent studies have suggested that NTs and their receptors are expressed in various types of stem cells mediating pivotal signaling events in stem cell biology. The concept of stem cell therapy has already attracted much attention as a potential strategy for the treatment of neurodegenerative diseases (NDs). Strikingly, NTs, proNTs, and their receptors are gaining interest as key regulators of stem cells differentiation, survival, self-renewal, plasticity, and migration. In this review, we elaborate the recent progress in understanding of NTs and their action on various stem cells. First, we provide current knowledge of NTs, proNTs, and their receptor isoforms and signaling pathways. Subsequently, we describe recent advances in the understanding of NT activities in various stem cells and their role in NDs, particularly Alzheimer's disease (AD) and Parkinson's disease (PD). Finally, we compile the implications of NTs and stem cells from a clinical perspective and discuss the challenges with regard to transplantation therapy for treatment of AD and PD.

[Stem cells in adults].

PubMed

Borge, O J; Funderud, S

2001-08-30

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

Quality Assurance in Stem Cell Banking: Emphasis on Embryonic and Induced Pluripotent Stem Cell Banking.

PubMed

Kallur, Therése; Blomberg, Pontus; Stenfelt, Sonya; Tryggvason, Kristian; Hovatta, Outi

2017-01-01

For quality assurance (QA) in stem cell banking, a planned system is needed to ensure that the banked products, stem cells, meet the standards required for research, clinical use, and commercial biotechnological applications. QA is process oriented, avoids, or minimizes unacceptable product defects, and particularly encompasses the management and operational systems of the bank, as well as the ethical and legal frameworks. Quality control (QC ) is product oriented and therefore ensures the stem cells of a bank are what they are expected to be. Testing is for controlling, not assuring, product quality, and is therefore a part of QC , not QA. Like QA, QC is essential for banking cells for quality research and translational application (Schwartz et al., Lancet 379:713-720, 2012). Human embryonic stem cells (hESCs), as cells derived from donated supernumerary embryos from in vitro fertilization (IVF) therapy, are different from other stem cell types in resulting from an embryo that has had two donors . This imposes important ethical and legal constraints on the utility of the cells, which, together with quite specific culture conditions, require special attention in the QA system. Importantly, although the origin and derivation of induced pluripotent stem cells (iPSCs ) differ from that of hESCs, many of the principles of QA for hESC banking are applicable to iPSC banking (Stacey et al., Cell Stem Cell 13:385-388, 2013). Furthermore, despite differences between the legal and regulatory frameworks for hESC and iPSC banking between different countries, the requirements for QA are being harmonized (Stacey et al., Cell Stem Cell 13:385-388, 2013; International Stem Cell Banking Initiative, Stem Cell Rev 5:301-314, 2009).

Stem cell plasticity.

PubMed

Lakshmipathy, Uma; Verfaillie, Catherine

2005-01-01

The central dogma in stem cell biology has been that cells isolated from a particular tissue can renew and differentiate into lineages of the tissue it resides in. Several studies have challenged this idea by demonstrating that tissue specific cell have considerable plasticity and can cross-lineage restriction boundary and give rise to cell types of other lineages. However, the lack of a clear definition for plasticity has led to confusion with several reports failing to demonstrate that a single cell can indeed differentiate into multiple lineages at significant levels. Further, differences between results obtained in different labs has cast doubt on some results and several studies still await independent confirmation. In this review, we critically evaluate studies that report stem cell plasticity using three rigid criteria to define stem cell plasticity; differentiation of a single cell into multiple cell lineages, functionality of differentiated cells in vitro and in vivo, robust and persistent engraft of transplanted cells.

When stem cells grow old: phenotypes and mechanisms of stem cell aging.

PubMed

Schultz, Michael B; Sinclair, David A

2016-01-01

All multicellular organisms undergo a decline in tissue and organ function as they age. An attractive theory is that a loss in stem cell number and/or activity over time causes this decline. In accordance with this theory, aging phenotypes have been described for stem cells of multiple tissues, including those of the hematopoietic system, intestine, muscle, brain, skin and germline. Here, we discuss recent advances in our understanding of why adult stem cells age and how this aging impacts diseases and lifespan. With this increased understanding, it is feasible to design and test interventions that delay stem cell aging and improve both health and lifespan. © 2016. Published by The Company of Biologists Ltd.

The UK Stem Cell Bank: a UK government-funded, international resource center for stem cell research.

PubMed

Stacey, Glyn; Hunt, Charles J

2006-01-01

The UK Stem Cell Bank is a UK Research Council-funded initiative that aims to provide ethically sourced and quality controlled stocks of cells for researchers and also establish seed stocks of cell lines for clinical trials. Whilst the Bank is prohibited from carrying out basic stem cell research (to avoid conflicts of interest) it is working to improve stem cell banking procedures including cryopreservation, characterization and quality control. The Bank also supports training activities and has provided the hub for the International Stem Cell Initiative, which includes 17 expert stem cell centers aiming to characterize a large number of human embryonic stem cell lines in a standardized way to improve our understanding of the characteristics of these cells.

Stemness of spermatogonial stem cells encapsulated in alginate hydrogel during cryopreservation.

PubMed

Pirnia, A; Parivar, K; Hemadi, M; Yaghmaei, P; Gholami, M

2017-06-01

This study investigated the effect of spermatogonial stem cell encapsulated in alginate hydrogel during cryopreservation, as cells were protected against damage during cryopreservation within the hydrogel. Spermatogonial stem cells were isolated from the testes of Balb/c mice pups (6 days old), purified in laminin-coated dishes and CD90.1 microbeads, encapsulated in alginate hydrogel and then cryopreserved. After thawing, cell viability and Spermatogonial stem cell (SSC) colony diameter were evaluated. After RNA was isolated and cDNA was synthesised, the expression of stemness genes was considered using RT real-time PCR. Finally, spermatogonial stem cells labelled with BrdU were transplanted to busulfan azoospermic mouse models. Lin28a and Sall4 genes were significantly upregulated after cryopreservation in alginate hydrogel. However, cell viability was significantly decreased. The diameter of colonies consisting of spermatogonial stem cells freeze-thawed in alginate microbeads showed no significant difference with fresh spermatogonial stem cells and the control group. The injection of freeze-thawed spermatogonial stem cells encapsulated in alginate hydrogel resulted in spermatogenesis recovery. Alginate mimics the extracellular matrices (ECM) for spermatogonial stem cells; therefore, it can support stemness potential during the cell cryopreservation process and restart spermatogenesis after transplantation. © 2016 Blackwell Verlag GmbH.

Interleukin-6 Regulates Adult Neural Stem Cell Numbers during Normal and Abnormal Post-natal Development.

PubMed

Storer, Mekayla A; Gallagher, Denis; Fatt, Michael P; Simonetta, Jaclin V; Kaplan, David R; Miller, Freda D

2018-05-08

Circulating systemic factors can regulate adult neural stem cell (NSC) biology, but the identity of these circulating cues is still being defined. Here, we have focused on the cytokine interleukin-6 (IL-6), since increased circulating levels of IL-6 are associated with neural pathologies such as autism and bipolar disorder. We show that IL-6 promotes proliferation of post-natal murine forebrain NSCs and that, when the IL-6 receptor is inducibly knocked out in post-natal or adult neural precursors, this causes a long-term decrease in forebrain NSCs. Moreover, a transient circulating surge of IL-6 in perinatal or adult mice causes an acute increase in neural precursor proliferation followed by long-term depletion of adult NSC pools. Thus, IL-6 signaling is both necessary and sufficient for adult NSC self-renewal, and acute perturbations in circulating IL-6, as observed in many pathological situations, have long-lasting effects on the size of adult NSC pools. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Somatic stem cell heterogeneity: diversity in the blood, skin and intestinal stem cell compartments

PubMed Central

Goodell, Margaret A.; Nguyen, Hoang; Shroyer, Noah

2017-01-01

Somatic stem cells replenish many tissues throughout life to repair damage and to maintain tissue homeostasis. Stem cell function is frequently described as following a hierarchical model in which a single master cell undergoes self-renewal and differentiation into multiple cell types and is responsible for most regenerative activity. However, recent data from studies on blood, skin and intestinal epithelium all point to the concomitant action of multiple types of stem cells with distinct everyday roles. Under stress conditions such as acute injury, the surprising developmental flexibility of these stem cells enables them to adapt to diverse roles and to acquire different regeneration capabilities. This paradigm shift raises many new questions about the developmental origins, inter-relationships and molecular regulation of these multiple stem cell types. PMID:25907613

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.

The role of donor characteristics and post-granulocyte colony-stimulating factor white blood cell counts in predicting the adverse events and yields of stem cell mobilization.

PubMed

Chen, Shu-Huey; Yang, Shang-Hsien; Chu, Sung-Chao; Su, Yu-Chieh; Chang, Chu-Yu; Chiu, Ya-Wen; Kao, Ruey-Ho; Li, Dian-Kun; Yang, Kuo-Liang; Wang, Tso-Fu

2011-05-01

Granulocyte colony-stimulating factor (G-CSF) is now widely used for stem cell mobilization. We evaluated the role of post-G-CSF white blood cell (WBC) counts and donor factors in predicting adverse events and yields associated with mobilization. WBC counts were determined at baseline, after the third and the fifth dose of G-CSF in 476 healthy donors. Donors with WBC ≥ 50 × 10(3)/μL post the third dose of G-CSF experienced more fatigue, myalgia/arthralgia, and chills, but final post-G-CSF CD34(+) cell counts were similar. Although the final CD34(+) cell count was higher in donors with WBC ≥ 50 × 10(3)/μL post the fifth G-CSF, the incidence of side effects was similar. Females more frequently experienced headache, nausea/anorexia, vomiting, fever, and lower final CD34(+) cell count than did males. Donors with body mass index (BMI) ≥ 25 showed higher incidences of sweat and insomnia as well as higher final CD34(+) cell counts. Donor receiving G-CSF ≥ 10 μg/kg tended to experience bone pain, headache and chills more frequently. Multivariate analysis indicated that female gender is an independent factor predictive of the occurrence of most side effects, except for ECOG > 1 and chills. Higher BMI was also an independent predictor for fatigue, myalgia/arthralgia, and sweat. Higher G-CSF dose was associated with bone pain, while the WBC count post the third G-CSF was associated with fatigue only. In addition, one donor in the study period did not complete the mobilization due to suspected anaphylactoid reaction. Observation for 1 h after the first injection of G-CSF is required to prevent complications from unpredictable side effects.

What's missing? Discussing stem cell translational research in educational information on stem cell "tourism".

PubMed

Master, Zubin; Zarzeczny, Amy; Rachul, Christen; Caulfield, Timothy

2013-01-01

Stem cell tourism is a growing industry in which patients pursue unproven stem cell therapies for a wide variety of illnesses and conditions. It is a challenging market to regulate due to a number of factors including its international, online, direct-to-consumer approach. Calls to provide education and information to patients, their families, physicians, and the general public about the risks associated with stem cell tourism are mounting. Initial studies examining the perceptions of patients who have pursued stem cell tourism indicate many are highly critical of the research and regulatory systems in their home countries and believe them to be stagnant and unresponsive to patient needs. We suggest that educational material should include an explanation of the translational research process, in addition to other aspects of stem cell tourism, as one means to help promote greater understanding and, ideally, curb patient demand for unproven stem cell interventions. The material provided must stress that strong scientific research is required in order for therapies to be safe and have a greater chance at being effective. Through an analysis of educational material on stem cell tourism and translational stem cell research from patient groups and scientific societies, we describe essential elements that should be conveyed in educational material provided to patients. Although we support the broad dissemination of educational material on stem cell translational research, we also acknowledge that education may simply not be enough to engender patient and public trust in domestic research and regulatory systems. However, promoting patient autonomy by providing good quality information to patients so they can make better informed decisions is valuable in itself, irrespective of whether it serves as an effective deterrent of stem cell tourism. © 2013 American Society of Law, Medicine & Ethics, Inc.

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

PubMed

Luzzani, Carlos D; Miriuka, Santiago G

2017-02-01

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

Stem Cell Technology in Cardiac Regeneration: A Pluripotent Stem Cell Promise.

PubMed

Duelen, Robin; Sampaolesi, Maurilio

2017-02-01

Despite advances in cardiovascular biology and medical therapy, heart disorders are the leading cause of death worldwide. Cell-based regenerative therapies become a promising treatment for patients affected by heart failure, but also underline the need for reproducible results in preclinical and clinical studies for safety and efficacy. Enthusiasm has been tempered by poor engraftment, survival and differentiation of the injected adult stem cells. The crucial challenge is identification and selection of the most suitable stem cell type for cardiac regenerative medicine. Human pluripotent stem cells (PSCs) have emerged as attractive cell source to obtain cardiomyocytes (CMs), with potential applications, including drug discovery and toxicity screening, disease modelling and innovative cell therapies. Lessons from embryology offered important insights into the development of stem cell-derived CMs. However, the generation of a CM population, uniform in cardiac subtype, adult maturation and functional properties, is highly recommended. Moreover, hurdles regarding tumorigenesis, graft cell death, immune rejection and arrhythmogenesis need to be overcome in clinical practice. Here we highlight the recent progression in PSC technologies for the regeneration of injured heart. We review novel strategies that might overcome current obstacles in heart regenerative medicine, aiming at improving cell survival and functional integration after cell transplantation. Copyright © 2017. Published by Elsevier B.V.

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

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

Varga, Nora; Vereb, Zoltan; Rajnavoelgyi, Eva

2011-10-28

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

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

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.

Therapeutic potential of dental stem cells

PubMed Central

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

2017-01-01

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

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

Hepatic stem/progenitor cells and stem-cell transplantation for the treatment of liver disease.

PubMed

Kakinuma, Sei; Nakauchi, Hiromitsu; Watanabe, Mamoru

2009-01-01

Allogeneic liver transplantation is still the only effective treatment available to patients with liver failure. However, because there is a serious shortage of liver donors, an alternative therapeutic approach is needed. Transplantation of mature hepatocytes has been evaluated in clinical trials, but the long-term efficacy remains unclear and the paucity of donor cells limits this strategy. Stem-cell transplantation is a more promising alternative approach. Several studies have provided information about the mechanism underlying the proliferation and differentiation of hepatic stem/progenitor cells. Moreover, in experimental models of liver disease, transplantation of hepatic stem/progenitor cells or hepatocyte-like cells derived from multipotent stem cells led to donor cell-mediated repopulation of the liver and improved survival rates. However, before stem-cell transplantation can be applied in the clinic to treat liver failure in humans, it will be necessary to overcome several difficulties associated with the technique.

Encapsulated Glucagon-Like Peptide-1-Producing Mesenchymal Stem Cells Have a Beneficial Effect on Failing Pig Hearts

PubMed Central

Wright, Elizabeth J.; Farrell, Kelly A.; Malik, Nadim; Kassem, Moustapha; Lewis, Andrew L.; Wallrapp, Christine

2012-01-01

Stem cell therapy is an exciting and emerging treatment option to promote post-myocardial infarction (post-MI) healing; however, cell retention and efficacy in the heart remain problematic. Glucagon-like peptide-1 (GLP-1) is an incretin hormone with cardioprotective properties but a short half-life in vivo. The effects of prolonged GLP-1 delivery from stromal cells post-MI were evaluated in a porcine model. Human mesenchymal stem cells immortalized and engineered to produce a GLP-1 fusion protein were encapsulated in alginate (bead-GLP-1 MSC) and delivered to coronary artery branches. Control groups were cell-free beads and beads containing unmodified MSCs (bead-MSC), n = 4–5 per group. Echocardiography confirmed left ventricular (LV) dysfunction at time of delivery in all groups. Four weeks after intervention, only the bead-GLP-1 MSC group demonstrated LV function improvement toward baseline and showed decreased infarction area compared with controls. Histological analysis showed reduced inflammation and a trend toward reduced apoptosis in the infarct zone. Increased collagen but fewer myofibroblasts were observed in infarcts of the bead-GLP-1 MSC and bead-MSC groups, and significantly more vessels per mm2 were noted in the infarct of the bead-GLP-1 MSC group. No differences were observed in myocyte cross-sectional area between groups. Post-MI delivery of GLP-1 encapsulated genetically modified MSCs provided a prolonged supply of GLP-1 and paracrine stem cell factors, which improved LV function and reduced epicardial infarct size. This was associated with increased angiogenesis and an altered remodeling response. Combined benefits of paracrine stem cell factors and GLP-1 were superior to those of stem cells alone. These results suggest that encapsulated genetically modified MSCs would be beneficial for recovery following MI. PMID:23197668

Induction of human umbilical Wharton's jelly-derived mesenchymal stem cells toward motor neuron-like cells.

PubMed

Bagher, Zohreh; Ebrahimi-Barough, Somayeh; Azami, Mahmoud; Mirzadeh, Hamid; Soleimani, Mansooreh; Ai, Jafar; Nourani, Mohammad Reza; Joghataei, Mohammad Taghi

2015-10-01

The most important property of stem cells from different sources is the capacity to differentiate into various cells and tissue types. However, problems including contamination, normal karyotype, and ethical issues cause many limitations in obtaining and using these cells from different sources. The cells in Wharton's jelly region of umbilical cord represent a pool source of primitive cells with properties of mesenchymal stem cells (MSCs). The aim of this study was to determine the potential of human Wharton's jelly-derived mesenchymal stem cells (WJMSCs) for differentiation to motor neuron cells. WJMSCs were induced to differentiate into motor neuron-like cells by using different signaling molecules and neurotrophic factors in vitro. Differentiated neurons were then characterized for expression of motor neuron markers including nestin, PAX6, NF-H, Islet 1, HB9, and choline acetyl transferase (ChAT) by quantitative reverse transcription PCR and immunocytochemistry. Our results showed that differentiated WJMSCs could significantly express motor neuron biomarkers in RNA and protein levels 15 d post induction. These results suggested that WJMSCs can differentiate to motor neuron-like cells and might provide a potential source in cell therapy for neurodegenerative disease.

[Progress in stem cells and regenerative medicine].

PubMed

Wang, Libin; Zhu, He; Hao, Jie; Zhou, Qi

2015-06-01

Stem cells have the ability to differentiate into all types of cells in the body and therefore have great application potential in regenerative medicine, in vitro disease modelling and drug screening. In recent years, stem cell technology has made great progress, and induced pluripotent stem cell technology revolutionizes the whole stem cell field. At the same time, stem cell research in our country has also achieved great progress and becomes an indispensable power in the worldwide stem cell research field. This review mainly focuses on the research progress in stem cells and regenerative medicine in our country since the advent of induced pluripotent stem cell technology, including induced pluripotent stem cells, transdifferentiation, haploid stem cells, and new gene editing tools.

Stem Cells as Drug Delivery Methods: Application of Stem Cell Secretome for Regeneration

PubMed Central

Tran, Christine; Damaser, Margot S.

2014-01-01

Mesenchymal stem cells (MSC) are a unique cell population defined by their ability to indefinitely self-renew, differentiate into multiple cell lineages, and form clonal cell populations. It was originally thought that this ability for broad plasticity defined the therapeutic potential of MSCs. However, an expanding body of recent literature has brought growing awareness to the remarkable array of bioactive molecules produced by stem cells. This protein milieu or “secretome” comprises a diverse host of cytokines, chemokines, angiogenic factors, and growth factors. The autocrine/paracrine role of these molecules is being increasingly recognized as key to the regulation of many physiological processes including directing endogenous and progenitor cells to sites of injury as well as mediating apoptosis, scarring, and tissue revascularization. In fact, the immunomodulatory and paracrine role of these molecules may predominantly account for the therapeutic effects of MSCs given that many in vitro and in vivo studies have demonstrated limited stem cell engraftment at the site of injury. While the study of such a vast protein array remains challenging, technological advances in the field of proteomics have greatly facilitated our ability to analyze and characterize the stem cell secretome. Thus, stem cells can be considered as tunable pharmacological storehouses useful for combinatorial drug manufacture and delivery. As a cell-free option for regenerative medicine therapies, stem cell secretome has shown great potential in a variety of clinical applications including the restoration of function in cardiovascular, neurodegenerative, oncologic, and genitourinary pathologies. PMID:25451858

The transcription factor Nerfin-1 prevents reversion of neurons into neural stem cells.

PubMed

Froldi, Francesca; Szuperak, Milan; Weng, Chen-Fang; Shi, Wei; Papenfuss, Anthony T; Cheng, Louise Y

2015-01-15

Cellular dedifferentiation is the regression of a cell from a specialized state to a more multipotent state and is implicated in cancer. However, the transcriptional network that prevents differentiated cells from reacquiring stem cell fate is so far unclear. Neuroblasts (NBs), the Drosophila neural stem cells, are a model for the regulation of stem cell self-renewal and differentiation. Here we show that the Drosophila zinc finger transcription factor Nervous fingers 1 (Nerfin-1) locks neurons into differentiation, preventing their reversion into NBs. Following Prospero-dependent neuronal specification in the ganglion mother cell (GMC), a Nerfin-1-specific transcriptional program maintains differentiation in the post-mitotic neurons. The loss of Nerfin-1 causes reversion to multipotency and results in tumors in several neural lineages. Both the onset and rate of neuronal dedifferentiation in nerfin-1 mutant lineages are dependent on Myc- and target of rapamycin (Tor)-mediated cellular growth. In addition, Nerfin-1 is required for NB differentiation at the end of neurogenesis. RNA sequencing (RNA-seq) and chromatin immunoprecipitation (ChIP) analysis show that Nerfin-1 administers its function by repression of self-renewing-specific and activation of differentiation-specific genes. Our findings support the model of bidirectional interconvertibility between neural stem cells and their post-mitotic progeny and highlight the importance of the Nerfin-1-regulated transcriptional program in neuronal maintenance. © 2015 Froldi et al.; Published by Cold Spring Harbor Laboratory Press.

Eckol suppresses maintenance of stemness and malignancies in glioma stem-like cells

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

Hyun, Kyung-Hwan; Yoon, Chang-Hwan; Kim, Rae-Kwon

A subpopulation of cancer cells with stem cell properties is responsible for tumor maintenance and progression, and may contribute to resistance to anticancer treatments. Thus, compounds that target cancer stem-like cells could be usefully applied to destroy cancer. In this study, we investigated the effect of Eckol, a phlorotannin compound, on stemness and malignancies in glioma stem-like cells. To determine whether Eckol targets glioma stem-like cells, we examined whether Eckol treatment could change the expression levels of glioma stem-like cell markers and self-renewal-related proteins as well as the sphere forming ability, and the sensitivity to anticancer treatments. Alterations in themore » malignant properties of sphere-derived cells by Eckol were also investigated by soft-agar colony forming assay, by xenograft assay in nude mice, and by cell invasion assay. Treatment of sphere-forming glioma cells with Eckol effectively decreased the sphere formation as well as the CD133{sup +} cell population. Eckol treatment suppressed expression of the glioma stem-like cell markers and the self-renewal-related proteins without cell death. Moreover, treatment of glioma stem-like cells with Eckol significantly attenuated anchorage-independent growth on soft agar and tumor formation in xenograft mice. Importantly, Eckol treatment effectively reduced the resistance of glioma stem-like cells to ionizing radiation and temozolomide. Treatment of glioma stem-like cells with Eckol markedly blocked both phosphoinositide 3-kinase-Akt and Ras-Raf-1-Erk signaling pathways. These results indicate that the natural phlorotannin Eckol suppresses stemness and malignancies in glioma stem-like cells, and thereby makes glioma stem-like cells more sensitive to anticancer treatments, providing novel therapeutic strategies targeting specifically cancer stem-like cells.« less

Establishment of mouse expanded potential stem cells

PubMed Central

Gao, Xuefei; Antunes, Liliana; Yu, Yong; Zhu, Zhexin; Wang, Juexuan; Kolodziejczyk, Aleksandra A.; Campos, Lia S.; Wang, Cui; Yang, Fengtang; Zhong, Zhen; Fu, Beiyuan; Eckersley-Maslin, Melanie A.; Woods, Michael; Tanaka, Yosuke; Chen, Xi; Wilkinson, Adam C.; Bussell, James; White, Jacqui; Ramirez-Solis, Ramiro; Reik, Wolf; Göttgens, Berthold; Teichmann, Sarah A.; Tam, Patrick P. L.; Nakauchi, Hiromitsu; Zou, Xiangang; Lu, Liming; Liu, Pentao

2018-01-01

Mouse embryonic stem cells derived from the epiblast1 contribute to the somatic lineages and the germline but are excluded from the extra-embryonic tissues that are derived from the trophectoderm and the primitive endoderm2 upon reintroduction to the blastocyst. Here we report that cultures of expanded potential stem cells can be established from individual eight-cell blastomeres, and by direct conversion of mouse embryonic stem cells and induced pluripotent stem cells. Remarkably, a single expanded potential stem cell can contribute both to the embryo proper and to the trophectoderm lineages in a chimaera assay. Bona fide trophoblast stem cell lines and extra-embryonic endoderm stem cells can be directly derived from expanded potential stem cells in vitro. Molecular analyses of the epigenome and single-cell transcriptome reveal enrichment for blastomere-specific signature and a dynamic DNA methylome in expanded potential stem cells. The generation of mouse expanded potential stem cells highlights the feasibility of establishing expanded potential stem cells for other mammalian species. PMID:29019987

Pluripotent stem cells and reprogrammed cells in farm animals.

PubMed

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

2011-08-01

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

Hepatic differentiation of pluripotent stem cells.

PubMed

Loya, Komal; Eggenschwiler, Reto; Ko, Kinarm; Sgodda, Malte; André, Francoise; Bleidissel, Martina; Schöler, Hans R; Cantz, Tobias

2009-10-01

In regenerative medicine pluripotent stem cells are considered to be a valuable self-renewing source for therapeutic cell transplantations, given that a functional organ-specific phenotype can be acquired by in vitro differentiation protocols. Furthermore, derivatives of pluripotent stem cells that mimic fetal progenitor stages could serve as an important tool to analyze organ development with in vitro approaches. Because of ethical issues regarding the generation of human embryonic stem (ES) cells, other sources for pluripotent stem cells are intensively studied. Like in less developed vertebrates, pluripotent stem cells can be generated from the female germline even in mammals, via parthenogenetic activation of oocytes. Recently, testis-derived pluripotent stem cells were derived from the male germline. Therefore, we compared two different hepatic differentiation approaches and analyzed the generation of definitive endoderm progenitor cells and their further maturation into a hepatic phenotype using murine parthenogenetic ES cells, germline-derived pluripotent stem cells, and ES cells. Applying quantitative RT-PCR, both germline-derived pluripotent cell lines show similar differentiation capabilities as normal murine ES cells and can be considered an alternative source for pluripotent stem cells in regenerative medicine.

Bioprinting for stem cell research

PubMed Central

Tasoglu, Savas; Demirci, Utkan

2012-01-01

Recently, there has been a growing interest to apply bioprinting techniques to stem cell research. Several bioprinting methods have been developed utilizing acoustics, piezoelectricity, and lasers to deposit living cells onto receiving substrates. Using these technologies, spatially defined gradients of immobilized proteins can be engineered to direct stem cell differentiation into multiple subpopulations of different lineages. Stem cells can also be patterned in a high-throughput manner onto flexible implementation patches for tissue regeneration or onto substrates with the goal of accessing encapsulated stem cell of interest for genomic analysis. Here, we review recent achievements with bioprinting technologies in stem cell research, and identify future challenges and potential applications including tissue engineering and regenerative medicine, wound healing, and genomics. PMID:23260439

[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.

Dietary Pectin Increases Intestinal Crypt Stem Cell Survival following Radiation Injury.

PubMed

Sureban, Sripathi M; May, Randal; Qu, Dongfeng; Chandrakesan, Parthasarathy; Weygant, Nathaniel; Ali, Naushad; Lightfoot, Stan A; Ding, Kai; Umar, Shahid; Schlosser, Michael J; Houchen, Courtney W

2015-01-01

Gastrointestinal (GI) mucosal damage is a devastating adverse effect of radiation therapy. We have recently reported that expression of Dclk1, a Tuft cell and tumor stem cell (TSC) marker, 24h after high dose total-body gamma-IR (TBI) can be used as a surrogate marker for crypt survival. Dietary pectin has been demonstrated to possess chemopreventive properties, whereas its radioprotective property has not been studied. The aim of this study was to determine the effects of dietary pectin on ionizing radiation (IR)-induced intestinal stem cell (ISC) deletion, crypt and overall survival following lethal TBI. C57BL/6 mice received a 6% pectin diet and 0.5% pectin drinking water (pre-IR mice received pectin one week before TBI until death; post-IR mice received pectin after TBI until death). Animals were exposed to TBI (14 Gy) and euthanized at 24 and 84h post-IR to assess ISC deletion and crypt survival respectively. Animals were also subjected to overall survival studies following TBI. In pre-IR treatment group, we observed a three-fold increase in ISC/crypt survival, a two-fold increase in Dclk1+ stem cells, increased overall survival (median 10d vs. 7d), and increased expression of Dclk1, Msi1, Lgr5, Bmi1, and Notch1 (in small intestine) post-TBI in pectin treated mice compared to controls. We also observed increased survival of mice treated with pectin (post-IR) compared to controls. Dietary pectin is a radioprotective agent; prevents IR-induced deletion of potential reserve ISCs; facilitates crypt regeneration; and ultimately promotes overall survival. Given the anti-cancer activity of pectin, our data support a potential role for dietary pectin as an agent that can be administered to patients receiving radiation therapy to protect against radiation-induces mucositis.

Lower Oncogenic Potential of Human Mesenchymal Stem Cells Derived from Cord Blood Compared to Induced Pluripotent Stem Cells

PubMed Central

Foroutan, T.; Najmi, M.; Kazemi, N.; Hasanlou, M.; Pedram, A.

2015-01-01

Background: In regenerative medicine, use of each of the mesenchymal stem cells derived from bone marrow, cord blood, and adipose tissue, has several cons and pros. Mesenchymal stem cells derived from cord blood have been considered the best source for precursor transplantation. Direct reprogramming of a somatic cell into induced pluripotent stem cells by over-expression of 6 transcription factors Oct4, Sox2, Klf4, lin28, Nanog, and c-Myc has great potential for regenerative medicine, eliminating the ethical issues of embryonic stem cells and the rejection problems of using non-autologous cells. Objective: To compare reprogramming and pluripotent markers OCT4, Sox-2, c-Myc, Klf4, Nanog, and lin28 in mesenchymal stem cells derived from cord blood and induced pluripotent stem cells. Methods: We analyzed the expression level of OCT4, Sox-2, c-Myc, Klf4, Nanog and lin28 genes in human mesenchymal stem cells derived from cord blood and induced pluripotent stem cells by cell culture and RT-PCR. Results: The expression level of pluripotent genes OCT4 and Sox-2, Nanog and lin28 in mesenchymal stem cells derived from cord blood were significantly higher than those in induced pluripotent stem cells. In contrast to OCT-4A and Sox-2, Nanog and lin28, the expression level of oncogenic factors c-Myc and Klf4 were significantly higher in induced pluripotent stem cells than in mesenchymal stem cells derived from cord blood. Conclusion: It could be concluded that mesenchymal stem cells derived from human cord blood have lower oncogenic potential compared to induced pluripotent stem cells. PMID:26306155

Interspecies chimera between primate embryonic stem cells and mouse embryos: Monkey ESCs engraft into mouse embryos, but not post-implantation fetuses

PubMed Central

Simerly, Calvin; McFarland, Dave; Castro, Carlos; Lin, Chih-Cheng; Redinger, Carrie; Jacoby, Ethan; Mich-Basso, Jocelyn; Orwig, Kyle; Mills, Parker; Ahrens, Eric; Navara, Chris; Schatten, Gerald

2016-01-01

Unequivocal evidence for pluripotency in which embryonic stem cells contribute to chimeric offspring has yet to be demonstrated in human or nonhuman primates (NHPs). Here, rhesus and baboons ESCs were investigated in interspecific mouse chimera generated by aggregation or blastocyst injection. Aggregation chimera produced mouse blastocysts with GFP-nhpESCs at the inner cell mass (ICM), and embryo transfers (ETs) generated dimly-fluorescencing abnormal fetuses. Direct injection of GFP-nhpESCs into blastocysts produced normal non-GFP-fluorescencing fetuses. Injected chimera showed >70% loss of GFP-nhpESCs after 21 h culture. Outgrowths of all chimeric blastocysts established distinct but separate mouse- and NHP-ESC colonies. Extensive endogenous autofluorescence compromised anti-GFP detection and PCR analysis did not detect nhpESCs in fetuses. NhpESCs localize to the ICM in chimera and generate pregnancies. Because primate ESCs do not engraft post-implantation, and also because endogenous autofluorescence results in misleading positive signals, interspecific chimera assays for pluripotency with primate stem cells is unreliable with the currently available ESCs. Testing primate ESCs reprogrammed into even more naïve states in these inter-specific chimera assays will be an important future endeavor. PMID:21543277

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

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

HPV-Induced Field Cancerisation: Transformation of Adult Tissue Stem Cell Into Cancer Stem Cell.

PubMed

Olivero, Carlotta; Lanfredini, Simone; Borgogna, Cinzia; Gariglio, Marisa; Patel, Girish K

2018-01-01

Field cancerisation was originally described as a basis for multiple head and neck squamous cell carcinoma (HNSCC) and is a pre-malignant phenomenon that is frequently attributable to oncogenic human papillomavirus (HPV) infection. Our work on β-HPV-induced cutaneous squamous cell carcinomas identified a novel Lrig1+ hair follicle junctional zone keratinocyte stem cell population as the basis for field cancerisation. Herein, we describe the ability for HPV to infect adult tissue stem cells in order to establish persistent infection and induce their proliferation and displacement resulting in field cancerisation. By review of the HPV literature, we reveal how this mechanism is conserved as the basis of field cancerisation across many tissues. New insights have identified the capacity for HPV early region genes to dysregulate adult tissue stem cell self-renewal pathways ensuring that the expanded population preserve its stem cell characteristics beyond the stem cell niche. HPV-infected cells acquire additional transforming mutations that can give rise to intraepithelial neoplasia (IEN), from environmental factors such as sunlight or tobacco induced mutations in skin and oral cavity, respectively. With establishment of IEN, HPV viral replication is sacrificed with loss of the episome, and the tissue is predisposed to multiple cancer stem cell-driven carcinomas.

Hematopoietic stem cells: can old cells learn new tricks?

PubMed

Ho, Anthony D; Punzel, Michael

2003-05-01

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

Hematopoietic cell differentiation from embryonic and induced pluripotent stem cells

PubMed Central

2013-01-01

Pluripotent stem cells, both embryonic stem cells and induced pluripotent stem cells, are undifferentiated cells that can self-renew and potentially differentiate into all hematopoietic lineages, such as hematopoietic stem cells (HSCs), hematopoietic progenitor cells and mature hematopoietic cells in the presence of a suitable culture system. Establishment of pluripotent stem cells provides a comprehensive model to study early hematopoietic development and has emerged as a powerful research tool to explore regenerative medicine. Nowadays, HSC transplantation and hematopoietic cell transfusion have successfully cured some patients, especially in malignant hematological diseases. Owing to a shortage of donors and a limited number of the cells, hematopoietic cell induction from pluripotent stem cells has been regarded as an alternative source of HSCs and mature hematopoietic cells for intended therapeutic purposes. Pluripotent stem cells are therefore extensively utilized to facilitate better understanding in hematopoietic development by recapitulating embryonic development in vivo, in which efficient strategies can be easily designed and deployed for the generation of hematopoietic lineages in vitro. We hereby review the current progress of hematopoietic cell induction from embryonic stem/induced pluripotent stem cells. PMID:23796405

The Stem Cell Club: a model for unrelated stem cell donor recruitment.

PubMed

Fingrut, Warren; Parmar, Simran; Cuperfain, Ari; Rikhraj, Kiran; Charman, Erin; Ptak, Emilie; Kahlon, Manjot; Graham, Alice; Luong, Susan; Wang, Yongjun George; Yu, Janice; Arora, Neha; Suppiah, Roopa; Li, Edward W; Lee, Anna; Welsh, Christopher; Benzaquen, Menachem; Thatcher, Alicia; Baharmand, Iman; Ladd, Aedan; Petraszko, Tanya; Allan, David; Messner, Hans

2017-12-01

Patients with blood, immune, or metabolic diseases may require a stem cell transplant as part of their treatment. However, 70% of patients do not have a suitable human leukocyte antigen match in their family, and need an unrelated donor. Individuals can register as potential donors at stem cell drives, where they provide consent and a tissue sample for human leukocyte antigen typing. The ideal donors are young, male, and from a diversity of ethnic backgrounds. However, in Canada, non-Caucasian males ages 17 to 35 years represent only 8.8% of listed donors. The Stem Cell Club is a non-profit organization founded in 2011 in Canada that aims to augment recruitment of the most needed donors. The initiative published a recruitment toolkit online (www.stemcellclub.ca). Currently, there are 12 chapters at universities across Canada. To date, the Stem Cell Club has recruited 6585 potential registrants, representing 1.63% of donors on Canada's donor-database. Of the recruited registrants, 58.3% were male; 60.3% of males self-reported as non-Caucasian, and 78.5% were ages 17 to 25 years. From 2015 to 2016, the initiative recruited 13.7% of all ethnically diverse males ages 17 to 35 years listed in Canada's donor database. Data from this initiative demonstrate sustainability and performance on key indicators of stem cell drive quality. The Stem Cell Club has developed a capacity to recruit 2600 donors annually, with the majority being males with a high degree of ethnic diversity. The initiative enhances the quality of Canada's unrelated donor-database, improving the chances that patients in need of an unrelated donor will find a match for transplant. The Stem Cell Club is a model relevant to recruitment organizations around the world. © 2017 AABB.

Stem cells in the Drosophila digestive system.

PubMed

Zeng, Xiankun; Chauhan, Chhavi; Hou, Steven X

2013-01-01

Adult stem cells maintain tissue homeostasis by continuously replenishing damaged, aged and dead cells in any organism. Five types of region and organ-specific multipotent adult stem cells have been identified in the Drosophila digestive system: intestinal stem cells (ISCs) in the posterior midgut; hindgut intestinal stem cells (HISCs) at the midgut/hindgut junction; renal and nephric stem cells (RNSCs) in the Malpighian Tubules; type I gastric stem cells (GaSCs) at foregut/midgut junction; and type II gastric stem cells (GSSCs) at the middle of the midgut. Despite the fact that each type of stem cell is unique to a particular organ, they share common molecular markers and some regulatory signaling pathways. Due to the simpler tissue structure, ease of performing genetic analysis, and availability of abundant mutants, Drosophila serves as an elegant and powerful model system to study complex stem cell biology. The recent discoveries, particularly in the Drosophila ISC system, have greatly advanced our understanding of stem cell self-renewal, differentiation, and the role of stem cells play in tissue homeostasis/regeneration and adaptive tissue growth.

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

Progress in myeloma stem cells

PubMed Central

Cruz, Richard Dela; Tricot, Guido; Zangari, Maurizio; Zhan, Fenghuang

2011-01-01

Multiple myeloma (MM) is the second most common hematologic malignancy in the United States and affects about 4 in 100,000 Americans. Even though much progress has been made in MM therapy, MM remains an incurable disease for the vast majority of patients. The existence of MM stem cell is considered one of the major causes of MM drug-resistance, leading to relapse. This highlights the importance and urgency of developing approaches to target MM stem cells. However, very little is known about the molecular characteristics of the MM stem cells, which makes it difficult to target MM stem cells therapeutically. Evidence of the existence of a myeloma stem cell has been provided by Matsui et al. showing that the CD138- and CD20+ fraction, which is a minor population of the MM cells, has a greater clonogenic potential and has the phenotype of a memory B-cell (CD19+, CD27+). In this review, we report recent progress of cell surface markers in cancer stem cells, especially in myeloma and the molecular mechanisms related to drug resistance and myeloma disease progression. PMID:22432075

[Embryonic stem cells and therapeutic cloning].

PubMed

Sunde, A; Eftedal, I

2001-08-30

Increased interest in the therapeutic use of human stem cells has emerged following significant progress in ongoing research. The cloning of a sheep, the isolation of human embryonic stem cells, and the discovery that adult stem cells may be reprogrammed taken together give substance to hopes that novel principles of treatment may be developed for a variety of serious conditions. Embryonic stem cells are derived from pre-embryos at the blastocyst stage and may give rise to all bodily tissues and cells. Animal models have demonstrated that embryonic stem cells when transplanted into adult hosts may differentiate and develop into cells and tissues applicable for treatment of a variety of conditions, including Parkinson's disease, multiple sclerosis, spinal injuries, cardiac stroke and cancer. Transplanted embryonic stem cells are exposed to immune reactions similar to those acting on organ transplants, hence immunosuppression of the recipient is generally required. It is, however, possible to obtain embryonic stem cells that are genetically identical to the patient's own cells by means of therapeutic cloning techniques. The nucleus from a somatic cell is transferred into an egg after removal of the egg's own genetic material. Under specific condition the egg will use genetic information from the somatic cell in organising the formation of a blastocyst which in turn generates embryonic stem cells. These cells have a genetic composition identical to that of the patient and are suitable for stem cell therapy.

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

PubMed

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

2014-01-01

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

[Stem cells--cloning, plasticity, bioethic].

PubMed

Pflegerl, Pamina; Keller, Thomas; Hantusch, Brigitte; Hoffmann, Thomas Sören; Kenner, Lukas

2008-01-01

Stem cells with certain characteristics have become promising tools for molecular medicine. They have the potential to self-regenerate and to differentiate into specific tissues. Besides their great potential, embryonic stem cells (ESC) run the risk of enhanced tumorigenesis. The use of human embryonic stem cells (hESC) is ethically problematic because their isolation involves the destruction of human embryos. Recently developed methods generate are able to pluripotent stem cells from fibroblasts. Alternatives for ESC are adult stem cells (ASC) derived from bone marrow, cord blood, amniotic fluid and other tissues. The following article is on the basis of testimony of Lukas Kenner for the German Bundestag about the use of ESC for research, therapy and drug development. Ethical aspects are taken into consideration.

Germline Stem Cells

PubMed Central

Spradling, Allan; Fuller, Margaret T.; Braun, Robert E.; Yoshida, Shosei

2011-01-01

Sperm and egg production requires a robust stem cell system that balances self-renewal with differentiation. Self-renewal at the expense of differentiation can cause tumorigenesis, whereas differentiation at the expense of self-renewal can cause germ cell depletion and infertility. In most organisms, and sometimes in both sexes, germline stem cells (GSCs) often reside in a defined anatomical niche. Factors within the niche regulate a balance between GSC self-renewal and differentiation. Asymmetric division of the germline stem cell to form daughter cells with alternative fates is common. The exception to both these tendencies is the mammalian testis where there does not appear to be an obvious anatomical niche and where GSC homeostasis is likely accomplished by a stochastic balance of self-renewal and differentiation and not by regulated asymmetric cell division. Despite these apparent differences, GSCs in all organisms share many common mechanisms, although not necessarily molecules, to guarantee survival of the germline. PMID:21791699

Nuclear Mechanics and Stem Cell Differentiation.

PubMed

Mao, Xinjian; Gavara, Nuria; Song, Guanbin

2015-12-01

Stem cells are characterized by their self-renewal and multi-lineage differentiation potential. Stem cell differentiation is a prerequisite for the application of stem cells in regenerative medicine and clinical therapy. In addition to chemical stimulation, mechanical cues play a significant role in regulating stem cell differentiation. The integrity of mechanical sensors is necessary for the ability of cells to respond to mechanical signals. The nucleus, the largest and stiffest cellular organelle, interacts with the cytoskeleton as a key mediator of cell mechanics. Nuclear mechanics are involved in the complicated interactions of lamins, chromatin and nucleoskeleton-related proteins. Thus, stem cell differentiation is intimately associated with nuclear mechanics due to its indispensable role in mechanotransduction and mechanical response. This paper reviews several main contributions of nuclear mechanics, highlights the hallmarks of the nuclear mechanics of stem cells, and provides insight into the relationship between nuclear mechanics and stem cell differentiation, which may guide clinical applications in the future.

EuroStemCell: A European infrastructure for communication and engagement with stem cell research.

PubMed

Barfoot, Jan; Doherty, Kate; Blackburn, C Clare

2017-10-01

EuroStemCell is a large and growing network of organizations and individuals focused on public engagement with stem cells and regenerative medicine - a fluid and contested domain, where scientific, political, ethical, legal and societal perspectives intersect. Rooted in the European stem cell research community, this project has developed collaborative and innovative approaches to information provision and direct and online engagement, that reflect and respond to the dynamic growth of the field itself. EuroStemCell started as the communication and outreach component of a research consortium and subsequently continued as a stand-alone engagement initiative. The involvement of established European stem cell scientists has grown year-on-year, facilitating their participation in public engagement by allowing them to make high-value contributions with broad reach. The project has now had sustained support by partners and funders for over twelve years, and thus provides a model for longevity in public engagement efforts. This paper considers the evolution of the EuroStemCell project in response to - and in dialogue with - its evolving environment. In it, we aim to reveal the mechanisms and approaches taken by EuroStemCell, such that others within the scientific community can explore these ideas and be further enabled in their own public engagement endeavours. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Challenges of T Cell Therapies for Virus-associated Diseases after Hematopoietic Stem Cell Transplantation

PubMed Central

Leen, Ann M.; Tripic, Tamara; Rooney, Cliona M.

2009-01-01

Importance of the field Hematopoietic stem cell transplantation (HSCT) is the treatment of choice for many hematological malignancies and genetic disorders. A majority of patients do not have a human leukocyte antigen (HLA) identical sibling donor, and alternative stem cell sources include HLA-matched or mismatched unrelated donors and haploidentical related donors. However, alternative donor HSCT are associated with three major complications (i) graft rejection, (ii) graft-versus-host disease (GvHD) and (iii) delayed immune reconstitution leading to viral infections and relapse. Areas covered in this review Graft rejection and the risk of GvHD can be significantly reduced by using intensive conditioning regimens, including in vivo T cell depletion as well as ex vivo T cell depletion of the graft. However, the benefits of removing alloreactive T cells from the graft are offset by the concomitant removal of T cells with anti-viral or anti-tumor activity as well as the profound delay in endogenous T cell recovery post-transplant. Thus, opportunistic infections, many of which are not amenable to conventional small-molecule therapeutics, are frequent in these patients and are associated with significant morbidity and high mortality rates. This review discusses current cell therapies to prevent or treat viral infections/reactivations post-transplant. What the reader will gain The reader will gain an understanding of the current state of cell therapy to prevent and treat viral infections post-HSCT, and will be introduced to preclinical studies designed to develop and validate new manufacturing procedures intended to improve therapeutic efficacy and reduce associated toxicities. Take home message Reconstitution of HSCT recipients with antigen-specific T cells, produced either by allodepletion or in vitro reactivation, can offer an effective strategy to provide both immediate and long-term protection without harmful alloreactivity. PMID:20132056

Pituitary stem cells drop their mask.

PubMed

Vankelecom, Hugo

2012-01-01

The pituitary gland represents the organism's endocrine hub, integrating central and peripheral inputs to generate the appropriate hormonal signals that govern key physiological processes. To meet the changing endocrine demands, the gland has to flexibly remodel its hormone-producing cell compartment. Mechanisms underlying pituitary cellular plasticity, as well as homeostatic turnover, are poorly understood. Similar to other tissues, resident stem cells may participate in the generation of newborn cells. Although in the past recurrently postulated to exist, pituitary stem cells remained obscure until the quest recently regained momentum, resulting in a surge of studies that designated very strong candidates for the stem/progenitor cell position. The cells identified express stem cell-associated markers and signaling factors, as well as transcriptional regulators that play essential roles during pituitary embryogenesis. They exhibit the stem cell properties of multilineage differentiation and prominent efflux capacity ("side population" phenotype), and display a topographical pattern reminiscent of niche-like configurations. Yet, the stem cell tenet of long-term self-renewal remains to be unequivocally demonstrated. Taken together, pituitary stem cells commence to drop their mask. While their "face gradually becomes visible, the "character" they play in the pituitary awaits further disclosure. The aim of this review is to highlight the recent progress in pituitary stem/progenitor cell identification by sketching the historical context, describing the new findings with inclusion of critical and cautionary reflections, proposing a tentative stem/progenitor cell model, and pointing out remaining gaps and challenges. The recent acceleration in pituitary stem cell research may announce an exciting era in this endocrine field.

International Society for Stem Cell Research

MedlinePlus

... cell and regenerative medicine community. More stem cell research Take a closer look Recent Blogs View All ... nonprofit organization & the voice of the stem cell research community The International Society for Stem Cell Research ( ...

Advanced three-dimensional culture of equine intestinal epithelial stem cells.

PubMed

Stewart, A Stieler; Freund, J M; Gonzalez, L M

2018-03-01

Intestinal epithelial stem cells are critical to epithelial repair following gastrointestinal injury. The culture of intestinal stem cells has quickly become a cornerstone of a vast number of new research endeavours that range from determining tissue viability to testing drug efficacy for humans. This study aims to describe the methods of equine stem cell culture and highlights the future benefits of these techniques for the advancement of equine medicine. To describe the isolation and culture of small intestinal stem cells into three-dimensional (3D) enteroids in horses without clinical gastrointestinal abnormalities. Descriptive study. Intestinal samples were collected by sharp dissection immediately after euthanasia. Intestinal crypts containing intestinal stem cells were dissociated from the underlying tissue layers, plated in a 3D matrix and supplemented with growth factors. After several days, resultant 3D enteroids were prepared for immunofluorescent imaging and polymerase chain reaction (PCR) analysis to detect and characterise specific cell types present. Intestinal crypts were cryopreserved immediately following collection and viability assessed. Intestinal crypts were successfully cultured and matured into 3D enteroids containing a lumen and budding structures. Immunofluorescence and PCR were used to confirm the existence of stem cells and all post mitotic, mature cell types, described to exist in the horse intestinal epithelium. Previously frozen crypts were successfully cultured following a freeze-thaw cycle. Tissues were all derived from normal horses. Application of this technique for the study of specific disease was not performed at this time. The successful culture of equine intestinal crypts into 3D "mini-guts" allows for in vitro studies of the equine intestine. Additionally, these results have relevance to future development of novel therapies that harness the regenerative potential of equine intestine in horses with gastrointestinal disease

Genetics of Gonadal Stem Cell Renewal

PubMed Central

Greenspan, Leah Joy; de Cuevas, Margaret

2015-01-01

Stem cells are necessary for the maintenance of many adult tissues. Signals within the stem cell microenvironment, or niche, regulate the self-renewal and differentiation capability of these cells. Misregulation of these signals through mutation or damage can lead to overgrowth or depletion of different stem cell pools. In this review, we focus on the Drosophila testis and ovary, both of which contain well-defined niches, as well as the mouse testis, which has become a more approachable stem cell system with recent technical advances. We discuss the signals that regulate gonadal stem cells in their niches, how these signals mediate self-renewal and differentiation under homeostatic conditions, and how stress, whether from mutations or damage, can cause changes in cell fate and drive stem cell competition. PMID:26355592

Earlier defibrotide initiation post-diagnosis of veno-occlusive disease/sinusoidal obstruction syndrome improves Day +100 survival following haematopoietic stem cell transplantation.

PubMed

Richardson, Paul G; Smith, Angela R; Triplett, Brandon M; Kernan, Nancy A; Grupp, Stephan A; Antin, Joseph H; Lehmann, Leslie; Miloslavsky, Maja; Hume, Robin; Hannah, Alison L; Nejadnik, Bijan; Soiffer, Robert J

2017-07-01

Hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a progressive, potentially fatal complication of conditioning for haematopoietic stem cell transplant (HSCT). The VOD/SOS pathophysiological cascade involves endothelial-cell activation and damage, and a prothrombotic-hypofibrinolytic state. Severe VOD/SOS (typically characterized by multi-organ dysfunction) may be associated with >80% mortality. Defibrotide is approved for treating severe hepatic VOD/SOS post-HSCT in the European Union, and for hepatic VOD/SOS with renal or pulmonary dysfunction post-HSCT in the United States. Previously, defibrotide (25 mg/kg/day in 4 divided doses for a recommended ≥21 days) was available through an expanded-access treatment protocol for patients with VOD/SOS. Data from this study were examined post-hoc to determine if the timing of defibrotide initiation post-VOD/SOS diagnosis affected Day +100 survival post-HSCT. Among 573 patients, defibrotide was started on the day of VOD/SOS diagnosis in approximately 30%, and within 7 days in >90%. The relationship between Day +100 survival and treatment initiation before/after specific days post-diagnosis showed superior survival when treatment was initiated closer to VOD/SOS diagnosis with a statistically significant trend over time for better outcomes with earlier treatment initiation (P < 0·001). These results suggest that initiation of defibrotide should not be delayed after diagnosis of VOD/SOS. © 2017 The Authors. British Journal of Haematology published by John Wiley & Sons Ltd.

Identification of Metastatic Tumor Stem Cell

DTIC Science & Technology

2010-09-01

addition to a tumor stem cell , an existence of a metastatic stem cell is predicted. Despite the critical importance of the concept, this idea has not been...isolating stem cell population from a unique set of breast tumor cell lines and by examining their metastatic behavior in an animal model. The overall...will (i) isolate stem - cell population from non-metastatic and metastatic cells of a pair of syngenic breast tumor cell lines, and test their metastatic

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

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

Polymer microarray technology for stem cell engineering

PubMed Central

Coyle, Robert; Jia, Jia; Mei, Ying

2015-01-01

Stem cells hold remarkable promise for applications in tissue engineering and disease modeling. During the past decade, significant progress has been made in developing soluble factors (e.g., small molecules and growth factors) to direct stem cells into a desired phenotype. However, the current lack of suitable synthetic materials to regulate stem cell activity has limited the realization of the enormous potential of stem cells. This can be attributed to a large number of materials properties (e.g., chemical structures and physical properties of materials) that can affect stem cell fate. This makes it challenging to design biomaterials to direct stem cell behavior. To address this, polymer microarray technology has been developed to rapidly identify materials for a variety of stem cell applications. In this article, we summarize recent developments in polymer array technology and their applications in stem cell engineering. Statement of significance Stem cells hold remarkable promise for applications in tissue engineering and disease modeling. In the last decade, significant progress has been made in developing chemically defined media to direct stem cells into a desired phenotype. However, the current lack of the suitable synthetic materials to regulate stem cell activities has been limiting the realization of the potential of stem cells. This can be attributed to the number of variables in material properties (e.g., chemical structures and physical properties) that can affect stem cells. Polymer microarray technology has shown to be a powerful tool to rapidly identify materials for a variety of stem cell applications. Here we summarize recent developments in polymer array technology and their applications in stem cell engineering. PMID:26497624

Epigenome analysis of pluripotent stem cells

PubMed Central

Ricupero, Christopher L.; Swerdel, Mavis R.; Hart, Ronald P.

2015-01-01

Summary Mis-regulation of gene expression due to epigenetic abnormalities has been linked with complex genetic disorders, psychiatric illness and cancer. In addition, the dynamic epigenetic changes that occur in pluripotent stem cells are believed to impact regulatory networks essential for proper lineage development. Chromatin immunoprecipitation (ChIP) is a technique used to isolate and enrich chromatin fragments using antibodies against specific chromatin modifications, such as DNA binding proteins or covalent histone modifications. Until recently, many ChIP protocols required millions of cells for each immunoprecipitation. This severely limited analysis of rare cell populations or post-mitotic, differentiated cell lines. Here, we describe a low cell number ChIP protocol with next generation sequencing and analysis, that has the potential to uncover novel epigenetic regulatory pathways that were previously difficult or impossible to obtain. PMID:23546758

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.

The Fountain of Stem Cell-Based Youth? Online Portrayals of Anti-Aging Stem Cell Technologies.

PubMed

Rachul, Christen M; Percec, Ivona; Caulfield, Timothy

2015-08-01

The hype surrounding stem cell science has created a market opportunity for the cosmetic industry. Cosmetic and anti-aging products and treatments that make claims regarding stem cell technology are increasingly popular, despite a lack of evidence for safety and efficacy of such products. This study explores how stem cell-based products and services are portrayed to the public through online sources, in order to gain insight into the key messages available to consumers. A content analysis of 100 web pages was conducted to examine the portrayals of stem cell-based cosmetic and anti-aging products and treatments. A qualitative discourse analysis of one web page further examined how language contributes to the portrayals of these products and treatments to public audiences. The majority of web pages portrayed stem cell-based products as ready for public use. Very few web pages substantiated claims with scientific evidence, and even fewer mentioned any risks or limitations associated with stem cell science. The discourse analysis revealed that the framing and use of metaphor obscures the certainty of the efficacy of and length of time for stem cell-based anti-aging technology to be publicly available. This study highlights the need to educate patients and the public on the current limits of stem cell applications in this context. In addition, generating scientific evidence for stem cell-based anti-aging and aesthetic applications is needed for optimizing benefits and minimizing adverse effects for the public. Having more evidence on efficacy and risks will help to protect patients who are eagerly seeking out these treatments. © 2015 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

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.

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.

Robust G2 pausing of adult stem cells in Hydra.

PubMed

Buzgariu, Wanda; Crescenzi, Marco; Galliot, Brigitte

2014-01-01

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

Stem cells: science, policy, and ethics

PubMed Central

Fischbach, Gerald D.; Fischbach, Ruth L.

2004-01-01

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

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.

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

PubMed Central

Patel, P

2006-01-01

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

Redox regulation of plant stem cell fate.

PubMed

Zeng, Jian; Dong, Zhicheng; Wu, Haijun; Tian, Zhaoxia; Zhao, Zhong

2017-10-02

Despite the importance of stem cells in plant and animal development, the common mechanisms of stem cell maintenance in both systems have remained elusive. Recently, the importance of hydrogen peroxide (H 2 O 2 ) signaling in priming stem cell differentiation has been extensively studied in animals. Here, we show that different forms of reactive oxygen species (ROS) have antagonistic roles in plant stem cell regulation, which were established by distinct spatiotemporal patterns of ROS-metabolizing enzymes. The superoxide anion (O2·-) is markedly enriched in stem cells to activate WUSCHEL and maintain stemness, whereas H 2 O 2 is more abundant in the differentiating peripheral zone to promote stem cell differentiation. Moreover, H 2 O 2 negatively regulates O2·- biosynthesis in stem cells, and increasing H 2 O 2 levels or scavenging O2·- leads to the termination of stem cells. Our results provide a mechanistic framework for ROS-mediated control of plant stem cell fate and demonstrate that the balance between O2·- and H 2 O 2 is key to stem cell maintenance and differentiation. © 2017 The Authors.

Stem cells in cardiac repair.

PubMed

Henning, Robert J

2011-01-01

Myocardial infarction is the leading cause of death among people in industrialized nations. Although the heart has some ability to regenerate after infarction, myocardial restoration is inadequate. Consequently, investigators are currently exploring the use of human embryonic stem cells (hESCs), skeletal myoblasts and adult bone marrow stem cells to limit infarct size. hESCs are pluripotent cells that can regenerate myocardium in infarcted hearts, attenuate heart remodeling and contribute to left ventricle (LV) systolic force development. Since hESCs can form heart teratomas, investigators are differentiating hESCs toward cardiac progenitor cells prior to transplantation into hearts. Large quantities of hESCs cardiac progenitor cells, however, must be generated, immune rejection must be prevented and grafts must survive over the long term to significantly improve myocardial performance. Transplanted autologous skeletal myoblasts can survive in infarcted myocardium in small numbers, proliferate, differentiate into skeletal myofibers and increase the LV ejection fraction. These cells, however, do not form electromechanical connections with host cardiomyocytes. Consequently, electrical re-entry can occur and cause cardiac arrhythmias. Autologous bone marrow mononuclear cells contain hematopoietic and mesenchymal stem cells. In several meta-analyses, patients with coronary disease who received autologous bone marrow cells by intracoronary injection show significant 3.7% (range: 1.9-5.4%) increases in LV ejection fraction, decreases in LV end-systolic volume of -4.8 ml (range: -1.4 to -8.2 ml) and reductions in infarct size of 5.5% (-1.9 to -9.1%), without experiencing arrhythmias. Bone marrow cells appear to release biologically active factors that limit myocardial damage. Unfortunately, bone marrow cells from patients with chronic diseases propagate poorly and can die prematurely. Substantial challenges must be addressed and resolved to advance the use of stem cells

Methods for Stem Cell Production and Therapy

NASA Technical Reports Server (NTRS)

Valluri, Jagan V. (Inventor); Claudio, Pier Paolo (Inventor)

2015-01-01

The present invention relates to methods for rapidly expanding a stem cell population with or without culture supplements in simulated microgravity conditions. The present invention relates to methods for rapidly increasing the life span of stem cell populations without culture supplements in simulated microgravity conditions. The present invention also relates to methods for increasing the sensitivity of cancer stem cells to chemotherapeutic agents by culturing the cancer stem cells under microgravity conditions and in the presence of omega-3 fatty acids. The methods of the present invention can also be used to proliferate cancer cells by culturing them in the presence of omega-3 fatty acids. The present invention also relates to methods for testing the sensitivity of cancer cells and cancer stem cells to chemotherapeutic agents by culturing the cancer cells and cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce tissue for use in transplantation by culturing stem cells or cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce cellular factors and growth factors by culturing stem cells or cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce cellular factors and growth factors to promote differentiation of cancer stem cells under microgravity conditions.

Non-myeloablative autologous haematopoietic stem cell transplantation expands regulatory cells and depletes IL-17 producing mucosal-associated invariant T cells in multiple sclerosis

PubMed Central

Abrahamsson, Sofia V.; Angelini, Daniela F.; Dubinsky, Amy N.; Morel, Esther; Oh, Unsong; Jones, Joanne L.; Carassiti, Daniele; Reynolds, Richard; Salvetti, Marco; Calabresi, Peter A.; Coles, Alasdair J.; Battistini, Luca; Martin, Roland; Burt, Richard K.

2013-01-01

Autologous haematopoietic stem cell transplantation has been tried as one experimental strategy for the treatment of patients with aggressive multiple sclerosis refractory to other immunotherapies. The procedure is aimed at ablating and repopulating the immune repertoire by sequentially mobilizing and harvesting haematopoietic stem cells, administering an immunosuppressive conditioning regimen, and re-infusing the autologous haematopoietic cell product. ‘Non-myeloablative’ conditioning regimens to achieve lymphocytic ablation without marrow suppression have been proposed to improve safety and tolerability. One trial with non-myeloablative autologous haematopoietic stem cell transplantation reported clinical improvement and inflammatory stabilization in treated patients with highly active multiple sclerosis. The aim of the present study was to understand the changes in the reconstituted immune repertoire bearing potential relevance to its mode of action. Peripheral blood was obtained from 12 patients with multiple sclerosis participating in the aforementioned trial and longitudinally followed for 2 years. We examined the phenotype and function of peripheral blood lymphocytes by cell surface or intracellular staining and multi-colour fluorescence activated cell sorting alone or in combination with proliferation assays. During immune reconstitution post-transplantation we observed significant though transient increases in the proportion of CD4+FoxP3+ T cells and CD56high natural killer cell subsets, which are cell subsets associated with immunoregulatory function. CD8+CD57+ cytotoxic T cells were persistently increased after therapy and were able to suppress CD4+ T cell proliferation with variable potency. In contrast, a CD161high proinflammatory CD8+ T cell subset was depleted at all time-points post-transplantation. Phenotypic characterization revealed that the CD161highCD8+ T cells were mucosal-associated invariant T cells, a novel cell population originating

Engineering stem cells for future medicine.

PubMed

Ricotti, Leonardo; Menciassi, Arianna

2013-03-01

Despite their great potential in regenerative medicine applications, stem cells (especially pluripotent ones) currently show a limited clinical success, partly due to a lack of biological knowledge, but also due to a lack of specific and advanced technological instruments able to overcome the current boundaries of stem cell functional maturation and safe/effective therapeutic delivery. This paper aims at describing recent insights, current limitations, and future horizons related to therapeutic stem cells, by analyzing the potential of different bioengineering disciplines in bringing stem cells toward a safe clinical use. First, we clarify how and why stem cells should be properly engineered and which could be in a near future the challenges and the benefits connected with this process. Second, we identify different routes toward stem cell differentiation and functional maturation, relying on chemical, mechanical, topographical, and direct/indirect physical stimulation. Third, we highlight how multiscale modeling could strongly support and optimize stem cell engineering. Finally, we focus on future robotic tools that could provide an added value to the extent of translating basic biological knowledge into clinical applications, by developing ad hoc enabling technologies for stem cell delivery and control.

Human hepatocytes derived from pluripotent stem cells: a promising cell model for drug hepatotoxicity screening.

PubMed

Gómez-Lechón, María José; Tolosa, Laia

2016-09-01

Drug-induced liver injury (DILI) is a frequent cause of failure in both clinical and post-approval stages of drug development, and poses a key challenge to the pharmaceutical industry. Current animal models offer poor prediction of human DILI. Although several human cell-based models have been proposed for the detection of human DILI, human primary hepatocytes remain the gold standard for preclinical toxicological screening. However, their use is hindered by their limited availability, variability and phenotypic instability. In contrast, pluripotent stem cells, which include embryonic and induced pluripotent stem cells (iPSCs), proliferate extensively in vitro and can be differentiated into hepatocytes by the addition of soluble factors. This provides a stable source of hepatocytes for multiple applications, including early preclinical hepatotoxicity screening. In addition, iPSCs also have the potential to establish genotype-specific cells from different individuals, which would increase the predictivity of toxicity assays allowing more successful clinical trials. Therefore, the generation of human hepatocyte-like cells derived from pluripotent stem cells seems to be promising for overcoming limitations of hepatocyte preparations, and it is expected to have a substantial repercussion in preclinical hepatotoxicity risk assessment in early drug development stages.

Ovarian cancer stem cells.

PubMed

Zeimet, A G; Reimer, D; Sopper, S; Boesch, M; Martowicz, A; Roessler, J; Wiedemair, A M; Rumpold, H; Untergasser, G; Concin, N; Hofstetter, G; Muller-Holzner, E; Fiegl, H; Marth, C; Wolf, D; Pesta, M; Hatina, J

2012-01-01

Because of its semi-solid character in dissemination and growth, advanced ovarian cancer with its hundreds of peritoneal tumor nodules and plaques appears to be an excellent in vivo model for studying the cancer stem cell hypothesis. The most important obstacle, however, is to adequately define and isolate these tumor-initiating cells endowed with the properties of anoikis-resistance and unlimited self-renewal. Until now, no universal single marker or marker constellation has been found to faithfully isolate (ovarian) cancer stem cells. As these multipotent cells are known to possess highly elaborated efflux systems for cytotoxic agents, these pump systems have been exploited to outline putative stem cells as a side-population (SP) via dye exclusion analysis. Furthermore, the cells in question have been isolated via flow cytometry on the basis of cell surface markers thought to be characteristic for stem cells.In the Vienna variant of the ovarian cancer cell line A2780 a proof-of-principle model with both a stable SP and a stable ALDH1A1+ cell population was established. Double staining clearly revealed that both cell fractions were not identical. Of note, A2780V cells were negative for expression of surface markers CD44 and CD117 (c-kit). When cultured on monolayers of healthy human mesothelial cells, green-fluorescence-protein (GFP)-transfected SP of A2780V exhibited spheroid-formation, whereas non-side-population (NSP) developed a spare monolayer growing over the healthy mesothelium. Furthermore, A2780V SP was found to be partially resistant to platinum. However, this resistance could not be explained by over-expression of the "excision repair cross-complementation group 1" (ERCC1) gene, which is essentially involved in the repair of platinated DNA damage. ERCC1 was, nonetheless, over-expressed in A2780V cells grown as spheres under stem cell-selective conditions as compared to adherent monolayers cultured under differentiating conditions. The same was true for

Comparative glycoproteomics of stem cells identifies new players in ricin toxicity.

PubMed

Stadlmann, Johannes; Taubenschmid, Jasmin; Wenzel, Daniel; Gattinger, Anna; Dürnberger, Gerhard; Dusberger, Frederico; Elling, Ulrich; Mach, Lukas; Mechtler, Karl; Penninger, Josef M

2017-09-28

Glycosylation, the covalent attachment of carbohydrate structures onto proteins, is the most abundant post-translational modification. Over 50% of human proteins are glycosylated, which alters their activities in diverse fundamental biological processes. Despite the importance of glycosylation in biology, the identification and functional validation of complex glycoproteins has remained largely unexplored. Here we develop a novel quantitative approach to identify intact glycopeptides from comparative proteomic data sets, allowing us not only to infer complex glycan structures but also to directly map them to sites within the associated proteins at the proteome scale. We apply this method to human and mouse embryonic stem cells to illuminate the stem cell glycoproteome. This analysis nearly doubles the number of experimentally confirmed glycoproteins, identifies previously unknown glycosylation sites and multiple glycosylated stemness factors, and uncovers evolutionarily conserved as well as species-specific glycoproteins in embryonic stem cells. The specificity of our method is confirmed using sister stem cells carrying repairable mutations in enzymes required for fucosylation, Fut9 and Slc35c1. Ablation of fucosylation confers resistance to the bioweapon ricin, and we discover proteins that carry a fucosylation-dependent sugar code for ricin toxicity. Mutations disrupting a subset of these proteins render cells ricin resistant, revealing new players that orchestrate ricin toxicity. Our comparative glycoproteomics platform, SugarQb, enables genome-wide insights into protein glycosylation and glycan modifications in complex biological systems.

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

PubMed

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

2010-01-01

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

Stem cells--clinical application and perspectives.

PubMed

Brehm, Michael; Zeus, Tobias; Strauer, Bodo Eckehard

2002-11-01

Augmentation of myocardial performance in experimental models of therapeutic infarction and heart failure has been achieved by transplantation of exogenous cells into damaged myocardium. The quest for suitable donor cells has prompted research into the use of both embryonic stem cells and adult somatic stem cells. Recently, there has been a growing body of evidence that multipotent somatic stem cells in adult bone marrow exhibit tremendous functional plasticity and can reprogram in a new environmental tissue niche to give rise to cell lineages specific for new organ site. This phenomenon has made huge impact on myocardial biology, while multipotent adult bone marrow hematopoeitic stem cells and mesechymal stem cells can repopulate infarcted rodent myocardium and differentiate into both cardiomyocytes and new blood vessels. These data, coupled with the identification of a putative primitive cardiac stem cell population in the adult human heart, may open the way for novel therapeutic modalities for enhancing myocardial performance and treating heart failure.

Cell Cycle Regulation of Stem Cells by MicroRNAs.

PubMed

Mens, Michelle M J; Ghanbari, Mohsen

2018-06-01

MicroRNAs (miRNAs) are a class of small non-coding RNA molecules involved in the regulation of gene expression. They are involved in the fine-tuning of fundamental biological processes such as proliferation, differentiation, survival and apoptosis in many cell types. Emerging evidence suggests that miRNAs regulate critical pathways involved in stem cell function. Several miRNAs have been suggested to target transcripts that directly or indirectly coordinate the cell cycle progression of stem cells. Moreover, previous studies have shown that altered expression levels of miRNAs can contribute to pathological conditions, such as cancer, due to the loss of cell cycle regulation. However, the precise mechanism underlying miRNA-mediated regulation of cell cycle in stem cells is still incompletely understood. In this review, we discuss current knowledge of miRNAs regulatory role in cell cycle progression of stem cells. We describe how specific miRNAs may control cell cycle associated molecules and checkpoints in embryonic, somatic and cancer stem cells. We further outline how these miRNAs could be regulated to influence cell cycle progression in stem cells as a potential clinical application.

Extinction models for cancer stem cell therapy

PubMed Central

Sehl, Mary; Zhou, Hua; Sinsheimer, Janet S.; Lange, Kenneth L.

2012-01-01

Cells with stem cell-like properties are now viewed as initiating and sustaining many cancers. This suggests that cancer can be cured by driving these cancer stem cells to extinction. The problem with this strategy is that ordinary stem cells are apt to be killed in the process. This paper sets bounds on the killing differential (difference between death rates of cancer stem cells and normal stem cells) that must exist for the survival of an adequate number of normal stem cells. Our main tools are birth–death Markov chains in continuous time. In this framework, we investigate the extinction times of cancer stem cells and normal stem cells. Application of extreme value theory from mathematical statistics yields an accurate asymptotic distribution and corresponding moments for both extinction times. We compare these distributions for the two cell populations as a function of the killing rates. Perhaps a more telling comparison involves the number of normal stem cells NH at the extinction time of the cancer stem cells. Conditioning on the asymptotic time to extinction of the cancer stem cells allows us to calculate the asymptotic mean and variance of NH. The full distribution of NH can be retrieved by the finite Fourier transform and, in some parameter regimes, by an eigenfunction expansion. Finally, we discuss the impact of quiescence (the resting state) on stem cell dynamics. Quiescence can act as a sanctuary for cancer stem cells and imperils the proposed therapy. We approach the complication of quiescence via multitype branching process models and stochastic simulation. Improvements to the τ-leaping method of stochastic simulation make it a versatile tool in this context. We conclude that the proposed therapy must target quiescent cancer stem cells as well as actively dividing cancer stem cells. The current cancer models demonstrate the virtue of attacking the same quantitative questions from a variety of modeling, mathematical, and computational perspectives

Extinction models for cancer stem cell therapy.

PubMed

Sehl, Mary; Zhou, Hua; Sinsheimer, Janet S; Lange, Kenneth L

2011-12-01

Cells with stem cell-like properties are now viewed as initiating and sustaining many cancers. This suggests that cancer can be cured by driving these cancer stem cells to extinction. The problem with this strategy is that ordinary stem cells are apt to be killed in the process. This paper sets bounds on the killing differential (difference between death rates of cancer stem cells and normal stem cells) that must exist for the survival of an adequate number of normal stem cells. Our main tools are birth-death Markov chains in continuous time. In this framework, we investigate the extinction times of cancer stem cells and normal stem cells. Application of extreme value theory from mathematical statistics yields an accurate asymptotic distribution and corresponding moments for both extinction times. We compare these distributions for the two cell populations as a function of the killing rates. Perhaps a more telling comparison involves the number of normal stem cells NH at the extinction time of the cancer stem cells. Conditioning on the asymptotic time to extinction of the cancer stem cells allows us to calculate the asymptotic mean and variance of NH. The full distribution of NH can be retrieved by the finite Fourier transform and, in some parameter regimes, by an eigenfunction expansion. Finally, we discuss the impact of quiescence (the resting state) on stem cell dynamics. Quiescence can act as a sanctuary for cancer stem cells and imperils the proposed therapy. We approach the complication of quiescence via multitype branching process models and stochastic simulation. Improvements to the τ-leaping method of stochastic simulation make it a versatile tool in this context. We conclude that the proposed therapy must target quiescent cancer stem cells as well as actively dividing cancer stem cells. The current cancer models demonstrate the virtue of attacking the same quantitative questions from a variety of modeling, mathematical, and computational perspectives

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.

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

PubMed

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

2017-02-08

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

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

PubMed Central

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

2017-01-01

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

Biomechanics of stem cells

NASA Astrophysics Data System (ADS)

Spector, A. A.; Yuan, D.; Somers, S.; Grayson, W. L.

2018-04-01

Stem cells play a key role in the healthy development and maintenance of organisms. They are also critically important in medical treatments of various diseases. It has been recently demonstrated that the mechanical factors such as forces, adhesion, stiffness, relaxation, etc. have significant effects on stem cell functions. Under physiological conditions, cells (stem cells) in muscles, heart, and blood vessels are under the action of externally applied strains. We consider the stem cell microenvironment and performance associated with their conversion (differentiation) into skeletal muscle cells. Two problems are studied by using mathematical models whose parameters are then optimized by fitting experiments. First, we present our analysis of the process of stem cell differentiation under the application of cyclic unidirectional strain. This process is interpreted as a transition through several (six) stages where each of them is defined in terms of expression of a set of factors typical to skeletal muscle cells. The stem cell evolution toward muscle cells is described by a system of nonlinear ODEs. The parameters of the model are determined by fitting the experimental data on the time course of expression of the factors under consideration. Second, we analyse the mechanical (relaxation) properties of a scaffold that serves as the microenvironment for stem cells differentiation into skeletal muscle cells. This scaffold (surrounded by a liquid solution) is composed of unidirectional fibers with pores between them. The relaxation properties of the scaffold are studied in an experiment where a long cylindrical specimen is loaded by the application of ramp displacement until the strain reaches a prescribed value. The magnitude of the corresponding load is recorded. The specimen is considered as transversely isotropic poroelastic cylinder whose force relaxation is associated with liquid diffusion through the pores. An analytical solution for the total force applied to

Phenotypic Plasticity Determines Cancer Stem Cell Therapeutic Resistance in Oral Squamous Cell Carcinoma.

PubMed

Biddle, Adrian; Gammon, Luke; Liang, Xiao; Costea, Daniela Elena; Mackenzie, Ian C

2016-02-01

Cancer stem cells (CSCs) drive tumour spread and therapeutic resistance, and can undergo epithelial-to-mesenchymal transition (EMT) and mesenchymal-to-epithelial transition (MET) to switch between epithelial and post-EMT sub-populations. Examining oral squamous cell carcinoma (OSCC), we now show that increased phenotypic plasticity, the ability to undergo EMT/MET, underlies increased CSC therapeutic resistance within both the epithelial and post-EMT sub-populations. The post-EMT CSCs that possess plasticity exhibit particularly enhanced therapeutic resistance and are defined by a CD44(high)EpCAM(low/-) CD24(+) cell surface marker profile. Treatment with TGFβ and retinoic acid (RA) enabled enrichment of this sub-population for therapeutic testing, through which the endoplasmic reticulum (ER) stressor and autophagy inhibitor Thapsigargin was shown to selectively target these cells. Demonstration of the link between phenotypic plasticity and therapeutic resistance, and development of an in vitro method for enrichment of a highly resistant CSC sub-population, provides an opportunity for the development of improved chemotherapeutic agents that can eliminate CSCs.

Phenotypic Plasticity Determines Cancer Stem Cell Therapeutic Resistance in Oral Squamous Cell Carcinoma

PubMed Central

Biddle, Adrian; Gammon, Luke; Liang, Xiao; Costea, Daniela Elena; Mackenzie, Ian C.

2016-01-01

Cancer stem cells (CSCs) drive tumour spread and therapeutic resistance, and can undergo epithelial-to-mesenchymal transition (EMT) and mesenchymal-to-epithelial transition (MET) to switch between epithelial and post-EMT sub-populations. Examining oral squamous cell carcinoma (OSCC), we now show that increased phenotypic plasticity, the ability to undergo EMT/MET, underlies increased CSC therapeutic resistance within both the epithelial and post-EMT sub-populations. The post-EMT CSCs that possess plasticity exhibit particularly enhanced therapeutic resistance and are defined by a CD44highEpCAMlow/− CD24+ cell surface marker profile. Treatment with TGFβ and retinoic acid (RA) enabled enrichment of this sub-population for therapeutic testing, through which the endoplasmic reticulum (ER) stressor and autophagy inhibitor Thapsigargin was shown to selectively target these cells. Demonstration of the link between phenotypic plasticity and therapeutic resistance, and development of an in vitro method for enrichment of a highly resistant CSC sub-population, provides an opportunity for the development of improved chemotherapeutic agents that can eliminate CSCs. PMID:26981578

Lgr proteins in epithelial stem cell biology.

PubMed

Barker, Nick; Tan, Shawna; Clevers, Hans

2013-06-01

The ultimate success of global efforts to exploit adult stem cells for regenerative medicine will depend heavily on the availability of robust, highly selective stem cell surface markers that facilitate the isolation of stem cells from human tissues. Any subsequent expansion or manipulation of isolated stem cells will also require an intimate knowledge of the mechanisms that regulate these cells, to ensure maintenance of their regenerative capacities and to minimize the risk of introducing undesirable growth traits that could pose health risks for patients. A subclass of leucine-rich repeat-containing G-protein-coupled receptor (Lgr) proteins has recently gained prominence as adult stem cell markers with crucial roles in maintaining stem cell functions. Here, we discuss the major impact that their discovery has had on our understanding of adult stem cell biology in various self-renewing tissues and in accelerating progress towards the development of effective stem cell therapies.

In vitro differentiation of primordial germ cells and oocyte-like cells from stem cells.

PubMed

Costa, José J N; Souza, Glaucinete B; Soares, Maria A A; Ribeiro, Regislane P; van den Hurk, Robert; Silva, José R V

2018-02-01

Infertility is the result of failure due to an organic disorder of the reproductive organs, especially their gametes. Recently, much progress has been made on generating germ cells, including oocytes, from various types of stem cells. This review focuses on advances in female germ cell differentiation from different kinds of stem cells, with emphasis on embryonic stem cells, adult stem cells, and induced pluripotent stem cells. The advantages and disadvantages of the derivation of female germ cells from several types of stem cells are also highlighted, as well as the ability of stem cells to generate mature and functional female gametes. This review shows that stem cell therapies have opened new frontiers in medicine, especially in the reproductive area, with the possibility of regenerating fertility.

Interspecies chimera between primate embryonic stem cells and mouse embryos: monkey ESCs engraft into mouse embryos, but not post-implantation fetuses.

PubMed

Simerly, Calvin; McFarland, Dave; Castro, Carlos; Lin, Chih-Cheng; Redinger, Carrie; Jacoby, Ethan; Mich-Basso, Jocelyn; Orwig, Kyle; Mills, Parker; Ahrens, Eric; Navara, Chris; Schatten, Gerald

2011-07-01

Unequivocal evidence for pluripotency in which embryonic stem cells contribute to chimeric offspring has yet to be demonstrated in human or nonhuman primates (NHPs). Here, rhesus and baboons ESCs were investigated in interspecific mouse chimera generated by aggregation or blastocyst injection. Aggregation chimera produced mouse blastocysts with GFP-nhpESCs at the inner cell mass (ICM), and embryo transfers (ETs) generated dimly-fluorescencing abnormal fetuses. Direct injection of GFP-nhpESCs into blastocysts produced normal non-GFP-fluorescencing fetuses. Injected chimera showed >70% loss of GFP-nhpESCs after 21 h culture. Outgrowths of all chimeric blastocysts established distinct but separate mouse- and NHP-ESC colonies. Extensive endogenous autofluorescence compromised anti-GFP detection and PCR analysis did not detect nhpESCs in fetuses. NhpESCs localize to the ICM in chimera and generate pregnancies. Because primate ESCs do not engraft post-implantation, and also because endogenous autofluorescence results in misleading positive signals, interspecific chimera assays for pluripotency with primate stem cells is unreliable with the currently available ESCs. Testing primate ESCs reprogrammed into even more naïve states in these inter-specific chimera assays will be an important future endeavor. Copyright © 2011 Elsevier B.V. All rights reserved.

Cancer stem cells, cancer cell plasticity and radiation therapy.

PubMed

Vlashi, Erina; Pajonk, Frank

2015-04-01

Since the first prospective identification of cancer stem cells in solid cancers the cancer stem cell hypothesis has reemerged as a research topic of increasing interest. It postulates that solid cancers are organized hierarchically with a small number of cancer stem cells driving tumor growth, repopulation after injury and metastasis. They give rise to differentiated progeny, which lack these features. The model predicts that for any therapy to provide cure, all cancer stem cells have to be eliminated while the survival of differentiated progeny is less critical. In this review we discuss recent reports challenging the idea of a unidirectional differentiation of cancer cells. These reports provide evidence supporting the idea that non-stem cancer cells exhibit a remarkable degree of plasticity that allows them to re-acquire cancer stem cell traits, especially in the context of radiation therapy. We summarize conditions under which differentiation is reversed and discuss the current knowledge of the underlying mechanisms. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of the Post-Spinal Cord Injury Microenvironment on the Differentiation Capacity of Human Neural Stem Cells Derived from Induced Pluripotent Stem Cells.

PubMed

López-Serrano, Clara; Torres-Espín, Abel; Hernández, Joaquim; Alvarez-Palomo, Ana B; Requena, Jordi; Gasull, Xavier; Edel, Michael J; Navarro, Xavier

2016-10-01

Spinal cord injury (SCI) causes loss of neural functions below the level of the lesion due to interruption of spinal pathways and secondary neurodegenerative processes. The transplant of neural stem cells (NSCs) is a promising approach for the repair of SCI. Reprogramming of adult somatic cells into induced pluripotent stem cells (iPSCs) is expected to provide an autologous source of iPSC-derived NSCs, avoiding the immune response as well as ethical issues. However, there is still limited information on the behavior and differentiation pattern of transplanted iPSC-derived NSCs within the damaged spinal cord. We transplanted iPSC-derived NSCs, obtained from adult human somatic cells, into rats at 0 or 7 days after SCI, and evaluated motor-evoked potentials and locomotion of the animals. We histologically analyzed engraftment, proliferation, and differentiation of the iPSC-derived NSCs and the spared tissue in the spinal cords at 7, 21, and 63 days posttransplant. Both transplanted groups showed a late decline in functional recovery compared to vehicle-injected groups. Histological analysis showed proliferation of transplanted cells within the tissue and that cells formed a mass. At the final time point, most grafted cells differentiated to neural and astroglial lineages, but not into oligodendrocytes, while some grafted cells remained undifferentiated and proliferative. The proinflammatory tissue microenviroment of the injured spinal cord induced proliferation of the grafted cells and, therefore, there are possible risks associated with iPSC-derived NSC transplantation. New approaches are needed to promote and guide cell differentiation, as well as reduce their tumorigenicity once the cells are transplanted at the lesion site.

In vivo differentiation of induced pluripotent stem cells into neural stem cells by chimera formation.

PubMed

Choi, Hyun Woo; Hong, Yean Ju; Kim, Jong Soo; Song, Hyuk; Cho, Ssang Gu; Bae, Hojae; Kim, Changsung; Byun, Sung June; Do, Jeong Tae

2017-01-01

Like embryonic stem cells, induced pluripotent stem cells (iPSCs) can differentiate into all three germ layers in an in vitro system. Here, we developed a new technology for obtaining neural stem cells (NSCs) from iPSCs through chimera formation, in an in vivo environment. iPSCs contributed to the neural lineage in the chimera, which could be efficiently purified and directly cultured as NSCs in vitro. The iPSC-derived, in vivo-differentiated NSCs expressed NSC markers, and their gene-expression pattern more closely resembled that of fetal brain-derived NSCs than in vitro-differentiated NSCs. This system could be applied for differentiating pluripotent stem cells into specialized cell types whose differentiation protocols are not well established.

Differential sensitivity of Glioma stem cells to Aurora kinase A inhibitors: implications for stem cell mitosis and centrosome dynamics.

PubMed

Mannino, Mariella; Gomez-Roman, Natividad; Hochegger, Helfrid; Chalmers, Anthony J

2014-07-01

Glioma stem-cell-like cells are considered to be responsible for treatment resistance and tumour recurrence following chemo-radiation in glioblastoma patients, but specific targets by which to kill the cancer stem cell population remain elusive. A characteristic feature of stem cells is their ability to undergo both symmetric and asymmetric cell divisions. In this study we have analysed specific features of glioma stem cell mitosis. We found that glioma stem cells appear to be highly prone to undergo aberrant cell division and polyploidization. Moreover, we discovered a pronounced change in the dynamic of mitotic centrosome maturation in these cells. Accordingly, glioma stem cell survival appeared to be strongly dependent on Aurora A activity. Unlike differentiated cells, glioma stem cells responded to moderate Aurora A inhibition with spindle defects, polyploidization and a dramatic increase in cellular senescence, and were selectively sensitive to Aurora A and Plk1 inhibitor treatment. Our study proposes inhibition of centrosomal kinases as a novel strategy to selectively target glioma stem cells. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

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.

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

PubMed

Zulewski, Henryk

2006-10-14

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

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

PubMed

Zulewski, Henryk

2007-03-02

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

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

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

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

2011-04-15

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

Manifestations of fulminant CD8 T-cell post-transplant lymphoproliferative disorder following the administration of rituximab for lymphadenopathy with a high level of Epstein-Barr Virus (EBV) replication after allogeneic hematopoietic stem cell transplantation.

PubMed

Tanaka, Tomoyuki; Takizawa, Jun; Miyakoshi, Shukuko; Kozakai, Takashi; Fuse, Kyoko; Shibasaki, Yasuhiko; Moriyama, Masato; Ohshima, Koichi; Toba, Ken; Furukawa, Tatsuo; Sone, Hirohito; Masuko, Masayoshi

2014-01-01

We herein report the case of a 22-year-old woman with severe aplastic anemia who underwent allogeneic hematopoietic stem cell transplantation (HSCT). After HSCT, the Epstein-Barr virus (EBV)-DNA load in the peripheral blood gradually increased, and the patient presented with a fever and lymphadenopathy on day 56 post-HSCT. Although we administered rituximab, her clinical condition worsened. After rituximab treatment, CD8 T-cells emerged and became dominant in the peripheral blood, some of which were positive on an EBV-specific tetramer analysis. However, an open biopsy of the lymphadenopathy lesions revealed the CD8 T-cells to be infected with EBV, exhibiting proliferation with oligoclonality. The patient ultimately died of multiple organ failure on day 99 post-HSCT.

System for tracking transplanted limbal epithelial stem cells in the treatment of corneal stem cell deficiency

NASA Astrophysics Data System (ADS)

Boadi, J.; Sangwal, V.; MacNeil, S.; Matcher, S. J.

2015-03-01

The prevailing hypothesis for the existence and healing of the avascular corneal epithelium is that this layer of cells is continually produced by stem cells in the limbus and transported onto the cornea to mature into corneal epithelium. Limbal Stem Cell Deficiency (LSCD), in which the stem cell population is depleted, can lead to blindness. LSCD can be caused by chemical and thermal burns to the eye. A popular treatment, especially in emerging economies such as India, is the transplantation of limbal stem cells onto damaged limbus with hope of repopulating the region. Hence regenerating the corneal epithelium. In order to gain insights into the success rates of this treatment, new imaging technologies are needed in order to track the transplanted cells. Optical Coherence Tomography (OCT) is well known for its high resolution in vivo images of the retina. A custom OCT system has been built to image the corneal surface, to investigate the fate of transplanted limbal stem cells. We evaluate two methods to label and track transplanted cells: melanin labelling and magneto-labelling. To evaluate melanin labelling, stem cells are loaded with melanin and then transplanted onto a rabbit cornea denuded of its epithelium. The melanin displays strongly enhanced backscatter relative to normal cells. To evaluate magneto-labelling the stem cells are loaded with magnetic nanoparticles (20-30nm in size) and then imaged with a custom-built, magneto-motive OCT system.

Placenta-an alternative source of stem cells

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

Matikainen, Tiina; Laine, Jarmo

2005-09-01

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

Stem Cells News Update: A Personal Perspective

PubMed Central

Wong, SC

2013-01-01

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

Stem cells news update: a personal perspective.

PubMed

Wong, Sc

2013-12-01

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

[Stem cell therapy in cardiovascular diseases].

PubMed

Vértesaljai, Márton; Piróth, Zsolt; Fontos, Géza; Andréka, Gyórgy; Font, Gusztáv; Szánthó, Gergely; Réti, Marienn; Masszi, Tamás; Andréka, Peter

2005-11-20

Myocardial infarction is the leading cause of congestive heart failure in the industrialized world. Current treatments fail to address the underlying scarring and cell loss, which are the causes of ischaemic heart failure. Recent interest has focused on stem cells, which are undifferentiated and pluripotent cells that can proliferate, potentially self-renew, and differentiate into cardiomyocytes and endothelial cells. Myocardial regeneration is the most widely studied and debated example of stem cell plasticity. Early reports from animal and clinical investigations disagree on the extent of myocardial renewal in adults, but evidence indicates that cardiomyocytes were generated in what was previously considered a postmitotic organ. So far, candidates for cardiac stem cell therapy have been limited to patients with acute myocardial infarction and chronic ischaemic heart failure. Currently, bone marrow stem cells seem to be the most attractive cell type for these patients. The cells may be delivered by means of direct surgical injection, intracoronary infusion, retrograde venous infusion, and transendocardial infusion. Stem cells may directly increase cardiac contractility or passively limit infarct expansion and remodeling. Early phase I clinical studies indicate that stem cell transplantation is feasible and may have beneficial effects on ventricular remodeling after myocardial infarction. Future randomized clinical trials will establish the magnitude of benefit and the effect on mortality after stem cell therapy.

Differentiation of isolated human umbilical cord mesenchymal stem cells into neural stem cells

PubMed Central

Chen, Song; Zhang, Wei; Wang, Ji-Ming; Duan, Hong-Tao; Kong, Jia-Hui; Wang, Yue-Xin; Dong, Meng; Bi, Xue; Song, Jian

2016-01-01

AIM To investigate whether umbilical cord human mesenchymal stem cell (UC-MSC) was able to differentiate into neural stem cell and neuron in vitro. METHODS The umbilical cords were obtained from pregnant women with their written consent and the approval of the Clinic Ethnics Committee. UC-MSC were isolated by adherent culture in the medium contains 20% fetal bovine serum (FBS), then they were maintained in the medium contain 10% FBS and induced to neural cells in neural differentiation medium. We investigated whether UC-MSC was able to differentiate into neural stem cell and neuron in vitro by using flow cytometry, reverse transcriptase-polymerase chain reaction (RT-PCR) and immunofluorescence (IF) analyzes. RESULTS A substantial number of UC-MSC was harvested using the tissue explants adherent method at about 2wk. Flow cytometric study revealed that these cells expressed common markers of MSCs, such as CD105 (SH2), CD73 (SH3) and CD90. After induction of differentiation of neural stem cells, the cells began to form clusters; RT-PCR and IF showed that the neuron specific enolase (NSE) and neurogenic differentiation 1-positive cells reached 87.3%±14.7% and 72.6%±11.8%, respectively. Cells showed neuronal cell differentiation after induced, including neuron-like protrusions, plump cell body, obviously and stronger refraction. RT-PCR and IF analysis showed that microtubule-associated protein 2 (MAP2) and nuclear factor-M-positive cells reached 43.1%±10.3% and 69.4%±19.5%, respectively. CONCLUSION Human umbilical cord derived MSCs can be cultured and proliferated in vitro and differentiate into neural stem cells, which may be a valuable source for cell therapy of neurodegenerative eye diseases. PMID:26949608

Cardiac Stem Cell Hybrids Enhance Myocardial Repair

PubMed Central

Quijada, Pearl; Salunga, Hazel T.; Hariharan, Nirmala; Cubillo, Jonathan D.; El-Sayed, Farid G.; Moshref, Maryam; Bala, Kristin M.; Emathinger, Jacqueline M.; La Torre, Andrea De; Ormachea, Lucia; Alvarez, Roberto; Gude, Natalie A.; Sussman, Mark A.

2015-01-01

Rationale Dual cell transplantation of cardiac progenitor cells (CPCs) and mesenchymal stem cells (MSCs) after infarction improves myocardial repair and performance in large animal models relative to delivery of either cell population. Objective To demonstrate that CardioChimeras (CCs) formed by fusion between CPCs and MSCs have enhanced reparative potential in a mouse model of myocardial infarction relative to individual stem cells or combined cell delivery. Methods and Results Two distinct and clonally derived CCs, CC1 and CC2 were utilized for this study. CCs improved left ventricular anterior wall thickness (AWT) at 4 weeks post injury, but only CC1 treatment preserved AWT at 18 weeks. Ejection fraction was enhanced at 6 weeks in CCs, and functional improvements were maintained in CCs and CPC + MSC groups at 18 weeks. Infarct size was decreased in CCs, whereas CPC + MSC and CPC parent groups remained unchanged at 12 weeks. CCs exhibited increased persistence, engraftment, and expression of early commitment markers within the border zone relative to combinatorial and individual cell population-injected groups. CCs increased capillary density and preserved cardiomyocyte size in the infarcted regions suggesting CCs role in protective paracrine secretion. Conclusions CCs merge the application of distinct cells into a single entity for cellular therapeutic intervention in the progression of heart failure. CCs are a novel cell therapy that improves upon combinatorial cell approaches to support myocardial regeneration. PMID:26228030

A network of heterochronic genes including Imp1 regulates temporal changes in stem cell properties

PubMed Central

Nishino, Jinsuke; Kim, Sunjung; Zhu, Yuan; Zhu, Hao; Morrison, Sean J

2013-01-01

Stem cell properties change over time to match the changing growth and regeneration demands of tissues. We showed previously that adult forebrain stem cell function declines during aging because of increased expression of let-7 microRNAs, evolutionarily conserved heterochronic genes that reduce HMGA2 expression. Here we asked whether let-7 targets also regulate changes between fetal and adult stem cells. We found a second let-7 target, the RNA binding protein IMP1, that is expressed by fetal, but not adult, neural stem cells. IMP1 expression was promoted by Wnt signaling and Lin28a expression and opposed by let-7 microRNAs. Imp1-deficient neural stem cells were prematurely depleted in the dorsal telencephalon due to accelerated differentiation, impairing pallial expansion. IMP1 post-transcriptionally inhibited the expression of differentiation-associated genes while promoting the expression of self-renewal genes, including Hmga2. A network of heterochronic gene products including Lin28a, let-7, IMP1, and HMGA2 thus regulates temporal changes in stem cell properties. DOI: http://dx.doi.org/10.7554/eLife.00924.001 PMID:24192035

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

Long-term cognitive effects of human stem cell transplantation in the irradiated brain.

PubMed

Acharya, Munjal M; Martirosian, Vahan; Christie, Lori-Ann; Limoli, Charles L

2014-09-01

Radiotherapy remains a primary treatment modality for the majority of central nervous system tumors, but frequently leads to debilitating cognitive dysfunction. Given the absence of satisfactory solutions to this serious problem, we have used human stem cell therapies to ameliorate radiation-induced cognitive impairment. Here, past studies have been extended to determine whether engrafted cells provide even longer-term benefits to cognition. Athymic nude rats were cranially irradiated (10 Gy) and subjected to intrahippocampal transplantation surgery 2 days later. Human embryonic stem cells (hESC) or human neural stem cells (hNSC) were transplanted, and animals were subjected to cognitive testing on a novel place recognition task 8 months later. Grafting of hNSC was found to provide long lasting cognitive benefits over an 8-month post-irradiation interval. At this protracted time, hNSC grafting improved behavioral performance on a novel place recognition task compared to irradiated animals not receiving stem cells. Engrafted hESC previously shown to be beneficial following a similar task, 1 and 4 months after irradiation, were not found to provide cognitive benefits at 8 months. Our findings suggest that hNSC transplantation promotes the long-term recovery of the irradiated brain, where intrahippocampal stem cell grafting helps to preserve cognitive function.

TOOTH (The Open study Of dental pulp stem cell Therapy in Humans): Study protocol for evaluating safety and feasibility of autologous human adult dental pulp stem cell therapy in patients with chronic disability after stroke.

PubMed

Nagpal, Anjali; Kremer, Karlea L; Hamilton-Bruce, Monica A; Kaidonis, Xenia; Milton, Austin G; Levi, Christopher; Shi, Songtao; Carey, Leeanne; Hillier, Susan; Rose, Miranda; Zacest, Andrew; Takhar, Parabjit; Koblar, Simon A

2016-07-01

Stroke represents a significant global disease burden. As of 2015, there is no chemical or biological therapy proven to actively enhance neurological recovery during the chronic phase post-stroke. Globally, cell-based therapy in stroke is at the stage of clinical translation and may improve neurological function through various mechanisms such as neural replacement, neuroprotection, angiogenesis, immuno-modulation, and neuroplasticity. Preclinical evidence in a rodent model of middle cerebral artery ischemic stroke as reported in four independent studies indicates improvement in neurobehavioral function with adult human dental pulp stem cell therapy. Human adult dental pulp stem cells present an exciting potential therapeutic option for improving post-stroke disability. TOOTH (The Open study Of dental pulp stem cell Therapy in Humans) will investigate the use of autologous stem cell therapy for stroke survivors with chronic disability, with the following objectives: (a) determine the maximum tolerable dose of autologous dental pulp stem cell therapy; (b) define that dental pulp stem cell therapy at the maximum tolerable dose is safe and feasible in chronic stroke; and (c) estimate the parameters of efficacy required to design a future Phase 2/3 clinical trial. TOOTH is a Phase 1, open-label, single-blinded clinical trial with a pragmatic design that comprises three stages: Stage 1 will involve the selection of 27 participants with middle cerebral artery ischemic stroke and the commencement of autologous dental pulp stem cell isolation, growth, and testing in sequential cohorts (n = 3). Stage 2 will involve the transplantation of dental pulp stem cell in each cohort of participants with an ascending dose and subsequent observation for a 6-month period for any dental pulp stem cell-related adverse events. Stage 3 will investigate the neurosurgical intervention of the maximum tolerable dose of autologous dental pulp stem cell followed by 9 weeks of intensive task

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.

Transbronchial biopsy in the management of pulmonary complications of hematopoietic stem cell transplantation

PubMed Central

O’Dwyer, David N.; Duvall, Adam S.; Xia, Meng; Hoffman, Timothy C.; Bloye, Kiernan S.; Bulte, Camille A.; Zhou, Xiaofeng; Murray, Susan; Moore, Bethany B.; Yanik, Gregory A.

2017-01-01

The utility of transbronchial biopsy in the management of pulmonary complications following hematopoietic stem cell transplantation has shown variable results. Herein, we examine the largest case series of patients undergoing transbronchial biopsy following hematopoietic stem cell transplantation. We performed a retrospective analysis of 130 transbronchial biopsy cases performed in patients with pulmonary complications post-hematopoietic stem cell transplantation. Logistic regression models were applied to examine diagnostic yield, odds of therapy change and complications. The most common histologic finding on transbronchial biopsy was a non-specific interstitial pneumonitis (n= 24 cases, 18%). Pathogens identified by transbronchial biopsy were rare, occurring in < 5% of cases. A positive transbronchial biopsy significantly increased the odds of a subsequent change in corticosteroid therapy (OR=3.12, 95% CI 1.18–8.23; p=0.02) but was not associated with a change in antibiotic therapy (OR=1.01, 95% CI 0.40–2.54; p=0.98) or changes in overall therapy (OR=1.92, 95% CI 0.79–4.70; p=0.15). Patients who underwent a transbronchial biopsy had increased odds of complications related to the bronchoscopy (OR=3.33, 95% CI 1.63–6.79; p=0.001). In conclusion, transbronchial biopsy may contribute to the diagnostic management of non-infectious lung injury post-hematopoietic stem cell transplantation, while its utility in the management of infectious pulmonary complications of HSCT remains low. PMID:29058699

Single-Cell Sequencing Technologies for Cardiac Stem Cell Studies.

PubMed

Liu, Tiantian; Wu, Hongjin; Wu, Shixiu; Wang, Charles

2017-11-01

Today with the rapid advancements in stem cell studies and the promising potential of using stem cells in clinical therapy, there is an increasing demand for in-depth comprehensive analysis on individual cell transcriptome and epigenome, as they play critical roles in a number of cell functions such as cell differentiation, growth, and reprogramming. The development of single-cell sequencing technologies has helped in revealing some exciting new perspectives in stem cells and regenerative medicine research. Among the various potential applications, single-cell analysis for cardiac stem cells (CSCs) holds tremendous promises in understanding the mechanisms of heart development and regeneration, which might light up the path toward cell therapy for cardiovascular diseases. This review briefly highlights the recent progresses in single-cell sequencing analysis technologies and their applications in CSC research.

Correlation between telomerase and mTOR pathway in cancer stem cells.

PubMed

Dogan, Fatma; Biray Avci, Cigir

2018-01-30

Cancer stem cells (CSCs), which are defined as a subset of tumor cells, are able to self-renew, proliferate, differentiate similar to normal stem cells. Therefore, targeting CSCs has been considered as a new approach in cancer therapy. The mammalian target of rapamycin (mTOR) is a receptor tyrosine kinase which plays an important role in regulating cell proliferation, differentiation, cell growth, self-renewal in CSCs. On the other hand, hTERT overactivation provides replicative feature and immortality to CSCs, so the stemness and replicative properties of CSCs depend on telomerase activity. Therefore hTERT/telomerase activity may become a universal biomarker for anticancer therapy and it is an attractive therapeutic target for CSCs. It is known that mTOR regulates telomerase activity at the translational and post-translational level. Researchers show that mTOR inhibitor rapamycin reduces telomerase activity without changing hTERT mRNA activity. Correlation between mTOR and hTERT is important for survival and immortality of cancer cells. In addition, the PI3K/AKT/mTOR signaling pathway and hTERT up-regulation are related with cancer stemness features and drug resistance. mTOR inhibitor and TERT inhibitor combination may construct a novel strategy in cancer stem cells and it can make a double effect on telomerase enzyme. Consequently, inhibition of PI3K/AKT/mTOR signaling pathway components and hTERT activation may prohibit CSC self-renewal and surpass CSC-mediated resistance in order to develop new cancer therapeutics. Copyright © 2017 Elsevier B.V. All rights reserved.

Stem cells: sources and applications.

PubMed

Vats, A; Tolley, N S; Polak, J M; Buttery, L D K

2002-08-01

Tissue engineering is a multidisciplinary area of research aimed at regeneration of tissues and restoration of function of organs through implantation of cells/tissues grown outside the body, or stimulating cells to grow into implanted matrix. In this short review, some of the most recent developments in the use of stem cells for tissue repair and regeneration will be discussed. There is no doubt that stem cells derived from adult and embryonic sources hold great therapeutic potential but it is clear that there is still much research required before their use is commonplace. There is much debate over adult versus embryonic stem cells and whether both are required. It is probably too early to disregard one or other of these cell sources. With regard to embryonic stem cells, the major concern relates to the ethics of their creation and the proposed practice of therapeutic cloning.

Targeting insulin resistance in type 2 diabetes via immune modulation of cord blood-derived multipotent stem cells (CB-SCs) in stem cell educator therapy: phase I/II clinical trial.

PubMed

Zhao, Yong; Jiang, Zhaoshun; Zhao, Tingbao; Ye, Mingliang; Hu, Chengjin; Zhou, Huimin; Yin, Zhaohui; Chen, Yana; Zhang, Ye; Wang, Shanfeng; Shen, Jie; Thaker, Hatim; Jain, Summit; Li, Yunxiang; Diao, Yalin; Chen, Yingjian; Sun, Xiaoming; Fisk, Mary Beth; Li, Heng

2013-07-09

The prevalence of type 2 diabetes (T2D) is increasing worldwide and creating a significant burden on health systems, highlighting the need for the development of innovative therapeutic approaches to overcome immune dysfunction, which is likely a key factor in the development of insulin resistance in T2D. It suggests that immune modulation may be a useful tool in treating the disease. In an open-label, phase 1/phase 2 study, patients (N=36) with long-standing T2D were divided into three groups (Group A, oral medications, n=18; Group B, oral medications+insulin injections, n=11; Group C having impaired β-cell function with oral medications+insulin injections, n=7). All patients received one treatment with the Stem Cell Educator therapy in which a patient's blood is circulated through a closed-loop system that separates mononuclear cells from the whole blood, briefly co-cultures them with adherent cord blood-derived multipotent stem cells (CB-SCs), and returns the educated autologous cells to the patient's circulation. Clinical findings indicate that T2D patients achieve improved metabolic control and reduced inflammation markers after receiving Stem Cell Educator therapy. Median glycated hemoglobin (HbA1C) in Group A and B was significantly reduced from 8.61%±1.12 at baseline to 7.25%±0.58 at 12 weeks (P=2.62E-06), and 7.33%±1.02 at one year post-treatment (P=0.0002). Homeostasis model assessment (HOMA) of insulin resistance (HOMA-IR) demonstrated that insulin sensitivity was improved post-treatment. Notably, the islet beta-cell function in Group C subjects was markedly recovered, as demonstrated by the restoration of C-peptide levels. Mechanistic studies revealed that Stem Cell Educator therapy reverses immune dysfunctions through immune modulation on monocytes and balancing Th1/Th2/Th3 cytokine production. Clinical data from the current phase 1/phase 2 study demonstrate that Stem Cell Educator therapy is a safe approach that produces lasting improvement in

Targeting insulin resistance in type 2 diabetes via immune modulation of cord blood-derived multipotent stem cells (CB-SCs) in stem cell educator therapy: phase I/II clinical trial

PubMed Central

2013-01-01

Background The prevalence of type 2 diabetes (T2D) is increasing worldwide and creating a significant burden on health systems, highlighting the need for the development of innovative therapeutic approaches to overcome immune dysfunction, which is likely a key factor in the development of insulin resistance in T2D. It suggests that immune modulation may be a useful tool in treating the disease. Methods In an open-label, phase 1/phase 2 study, patients (N = 36) with long-standing T2D were divided into three groups (Group A, oral medications, n = 18; Group B, oral medications + insulin injections, n = 11; Group C having impaired β-cell function with oral medications + insulin injections, n = 7). All patients received one treatment with the Stem Cell Educator therapy in which a patient’s blood is circulated through a closed-loop system that separates mononuclear cells from the whole blood, briefly co-cultures them with adherent cord blood-derived multipotent stem cells (CB-SCs), and returns the educated autologous cells to the patient’s circulation. Results Clinical findings indicate that T2D patients achieve improved metabolic control and reduced inflammation markers after receiving Stem Cell Educator therapy. Median glycated hemoglobin (HbA1C) in Group A and B was significantly reduced from 8.61% ± 1.12 at baseline to 7.25% ± 0.58 at 12 weeks (P = 2.62E-06), and 7.33% ± 1.02 at one year post-treatment (P = 0.0002). Homeostasis model assessment (HOMA) of insulin resistance (HOMA-IR) demonstrated that insulin sensitivity was improved post-treatment. Notably, the islet beta-cell function in Group C subjects was markedly recovered, as demonstrated by the restoration of C-peptide levels. Mechanistic studies revealed that Stem Cell Educator therapy reverses immune dysfunctions through immune modulation on monocytes and balancing Th1/Th2/Th3 cytokine production. Conclusions Clinical data from the current phase 1/phase 2 study demonstrate that Stem Cell Educator

Stem Cell Research: A Novel Boulevard towards Improved Bovine Mastitis Management

PubMed Central

Sharma, Neelesh; Jeong, Dong Kee

2013-01-01

The dairy industry is a multi-billion dollar industry catering the nutritional needs of all age groups globally through the supply of milk. Clinical mastitis has a severe impact on udder tissue and is also an animal welfare issue. Moreover, it significantly reduces animal value and milk production. Mammary tissue damage reduces the number and activity of epithelial cells and consequently contributes to decreased milk production. The high incidence, low cure rate of this highly economic and sometimes deadly disease is an alarming for dairy sector as well as policy makers. Bovine mammary epithelial cells (MECs) and their stem cells are very important in milk production and bioengineering. The adult mammary epithelium consists of two main cell types; an inner layer of luminal epithelial cells, which produce the milk during lactation, and an outer layer of myoepithelial cells resting on a basement membrane, which are responsible for pushing the milk through the ductal network to the teat cistern. Inner layer of columner/luminal cells of bovine MECs, is characterized by cytokeratin18, 19 (CK18, CK19) and outer layer such as myoepithelial cells which are characterized by CK14, α-smooth muscle actin (α-SMA) and p63. Much work has been done in mouse and human, on mammary gland stem cell research, particularly in cancer therapy, but stem cell research in bovine is still in its infancy. Such stem/progenitor cell discoveries in human and mouse mammary gland bring some hope for application in bovines. These progenitors may be therapeutically adopted to correct the structural/cytological defects in the bovine udder due to mastitis. In the present review we focused on various kinds of stem/progenitor cells which can have therapeutic utility and their possibilities to use as a potential stem cell therapy in the management of bovine post-mastitis damage in orders to restore milk production. The possibilities of bovine mammary stem cell therapy offers significant potential for

Stem cell research: a novel boulevard towards improved bovine mastitis management.

PubMed

Sharma, Neelesh; Jeong, Dong Kee

2013-01-01

The dairy industry is a multi-billion dollar industry catering the nutritional needs of all age groups globally through the supply of milk. Clinical mastitis has a severe impact on udder tissue and is also an animal welfare issue. Moreover, it significantly reduces animal value and milk production. Mammary tissue damage reduces the number and activity of epithelial cells and consequently contributes to decreased milk production. The high incidence, low cure rate of this highly economic and sometimes deadly disease is an alarming for dairy sector as well as policy makers. Bovine mammary epithelial cells (MECs) and their stem cells are very important in milk production and bioengineering. The adult mammary epithelium consists of two main cell types; an inner layer of luminal epithelial cells, which produce the milk during lactation, and an outer layer of myoepithelial cells resting on a basement membrane, which are responsible for pushing the milk through the ductal network to the teat cistern. Inner layer of columner/luminal cells of bovine MECs, is characterized by cytokeratin18, 19 (CK18, CK19) and outer layer such as myoepithelial cells which are characterized by CK14, α-smooth muscle actin (α-SMA) and p63. Much work has been done in mouse and human, on mammary gland stem cell research, particularly in cancer therapy, but stem cell research in bovine is still in its infancy. Such stem/progenitor cell discoveries in human and mouse mammary gland bring some hope for application in bovines. These progenitors may be therapeutically adopted to correct the structural/cytological defects in the bovine udder due to mastitis. In the present review we focused on various kinds of stem/progenitor cells which can have therapeutic utility and their possibilities to use as a potential stem cell therapy in the management of bovine post-mastitis damage in orders to restore milk production. The possibilities of bovine mammary stem cell therapy offers significant potential for

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

Quality of life of patients with graft-versus-host disease (GvHD) post-hematopoietic stem cell transplantation.

PubMed

Proença, Sibéli de Fátima Ferraz Simão; Machado, Celina Mattos; Coelho, Raquel de Castro Figueiredo Pereira; Sarquis, Leila Maria Mansano; Guimarães, Paulo Ricardo Bittencourt; Kalinke, Luciana Puchalski

2016-01-01

Assessing the quality of life of adult patients with hematological cancer in the 100 days after transplantation of hematopoietic stem cells and verifying whether the variable graft-versus-host disease (GvHD) is predictive of worse results. An observational correlational and quantitative study with 36 adult participants diagnosed with hematologic cancer who underwent hematopoietic stem cell transplantation from September 2013 to June 2015. The mean age was 37 years, 52.78% were female, and 61.11% were diagnosed with leukemia. Quality of life scores showed a significant impact between pre-transplantation and pre-hospital discharge, and also within the 100 days post-transplantation. The statistical analysis between the scores for the groups with and without GvHD showed a significant difference between the presence of the complication and worse results. Quality of life is altered as a result of hematopoietic stem cells transplantation, especially in patients who have graft-versus-host disease. Avaliar a qualidade de vida de pacientes adultos com câncer hematológico nos 100 dias do transplante de células-tronco hematopoéticas e verificar se a variável doença do enxerto contra o hospedeiro é preditiva de piores resultados. Estudo observacional, correlacional e quantitativo, com 36 participantes adultos, diagnosticados com câncer hematológico que se submeteram ao transplante de células-tronco hematopoéticas de setembro de 2013 a junho de 2015. A média de idade foi 37 anos, 52,78% eram do sexo feminino, e 61,11% com diagnóstico de leucemia. Os escores de qualidade de vida demonstraram impacto significativo entre o pré-transplante e a pré-alta hospitalar e entre os 100 dias pós-transplante. A análise estatística entre os escores dos grupos com e sem doença do enxerto contra o hospedeiro evidenciou significância entre a presença desta complicação e piores resultados. A qualidade de vida é alterada em decorrência do transplante de c

The fate of mesenchymal stem cells transplanted into immunocompetent neonatal mice: implications for skeletal gene therapy via stem cells.

PubMed

Niyibizi, Christopher; Wang, Sujing; Mi, Zhibao; Robbins, Paul D

2004-06-01

To explore the feasibility of skeletal gene and cell therapies, we transduced murine bone marrow-derived mesenchymal stem cells (MSCs) with a retrovirus carrying the enhanced green fluorescent protein and zeocin-resistance genes prior to transplantation into 2-day-old immunocompetent neonatal mice. Whole-body imaging of the recipient mice at 7 days post-systemic cell injection demonstrated a wide distribution of the cells in vivo. Twenty-five days posttransplantation, most of the infused cells were present in the lung as assessed by examination of the cells cultured from the lungs of the recipient mice. The cells persisted in lung and maintained a high level of gene expression and could be recovered from the recipient mice at 150 days after cell transplantation. A significant number of GFP-positive cells were also present in the bones of the recipient mice at 35 days post-cell transplantation. Recycling of the cells recovered from femurs of the recipient mice at 25 days posttransplantation by repeated injections into different neonatal mice resulted in the isolation of a clone of cells that was detected in bone and cartilage, but not in lung and liver after systemic injection. These data demonstrate that MSCs persist in immunocompetent neonatal mice, maintain a high level of gene expression, and may participate in skeletal growth and development of the recipient animals.

Skin Stem Cells: At the Frontier Between the Laboratory and Clinical Practice. Part 1: Epidermal Stem Cells.

PubMed

Pastushenko, I; Prieto-Torres, L; Gilaberte, Y; Blanpain, C

2015-11-01

Stem cells are characterized by their ability to self-renew and differentiate into the different cell lineages of their tissue of origin. The discovery of stem cells in adult tissues, together with the description of specific markers for their isolation, has opened up new lines of investigation, expanding the horizons of biomedical research and raising new hope in the treatment of many diseases. In this article, we review in detail the main characteristics of the stem cells that produce the specialized cells of the skin (epidermal, mesenchymal, and melanocyte stem cells) and their potential implications and applications in diseases affecting the skin. Part I deals with the principal characteristics and potential applications of epidermal stem cells in dermatology. Copyright © 2015 Elsevier España, S.L.U. and AEDV. All rights reserved.

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.

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.

Mismatched related hematopoietic stem cell transplantation in primary immunodeficiency.

PubMed

Wahadneh, Adel M; Bin Dahman, Haifa A; Abu Shukear, Mohammed E; Habahbeh, Zeyad M; Ajarmeh, Mohammad A; Zyood, Raed M; Habashneh, Mueen S

2013-11-01

Hematopoietic stem cell transplantation (HSCT) is the definitive therapy for a variety of primary immunodeficiency syndromes (PIDs). However, no more than 30% of the patients will have a human leukocyte antigen (HLA)-identical sibling. We retrospectively analyzed our results of ten patients with PID; severe combined immunodeficiency (SCID) (n = 7), hyper IgM (HIgM) (n = 1) and combined immunodeficiency (CID) (n = 2), who lacked a fully matched donor and underwent mismatched related HSCT during the period from 2008 to 2010. The median age at the time of transplantation ranged between 3 and 84 months (median 6.5 months). Peripheral blood stem cells (PBSC) were used in all HSCTs. The mean value of the peripheral CD34+ cells infused was 9.19 × 10 (6) /kg recipient weight. Patients received different conditioning protocols. All patients received anti graft versus host disease (GVHD) prophylaxis and all were engrafted. Mixed chimerism (5-55%) was noticed. GVHD was observed in 50% of the patients. Post-transplant follow-up ranged from 3 weeks to 36 months (median 15 months). Five patients are still alive while one patient developed engraftment syndrome followed by graft slippage for which a second transplant with CD34+ stem cells 5.8 × 10 (6) /kg recipient's weight was infused. The others died from sepsis and transplant-related complications. Immune reconstitution was noticed in four patients. In conclusion, HLA-haploidentical stem cell transplantation may be feasible, with appropriate GVHD prophylaxis, for patients with PID who lack a fully matched donor.

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.

Cell of Origin and Cancer Stem Cell Phenotype in Medulloblastomas

DTIC Science & Technology

2015-07-01

dominant role over some oncogene function.In addition, we recently reported that cancer stem cells (CSCs)- stem cell like cells in tumors that have stem ... cell properties and tumor initiating ability- retain epigenetic memories of their cells of origin (Chow et al., 2014). We showed that CSCs derived from

Stem cells, blood vessels, and angiogenesis as major determinants for musculoskeletal tissue repair.

PubMed

Huard, Johnny

2018-05-22

This manuscript summarizes 20 years of research from my laboratories at the University of Pittsburgh and more recently, at the University of Texas Health Science Center at Houston and the Steadman Philippon Research Institute in Vail, Colorado. The discovery of muscle-derived stem cells (MDSCs) did not arise from a deliberate search to find a novel population of muscle cells with high regenerative potential, but instead was conceived in response to setbacks encountered while working in muscle cell transplantation for Duchenne muscular dystrophy (DMD). DMD is a devastating inherited X-linked muscle disease characterized by progressive muscle weakness due to lack of dystrophin expression in muscle fiber sarcolemma. Although the transplantation of normal myoblasts into dystrophin-deficient muscle can restore dystrophin, this approach has been hindered by limited survival (less than 1%) of the injected cells. The fact that 99% of the cells were not surviving implantation was seen as a major weakness with this technology by most. My research team decided to investigate which cells represent the 1% of the cells surviving post-implantation. We have subsequently confirmed that the few cells which exhibit high survival post-implantation also display stem cell characteristics, and were termed "muscle-derived stem cells" or MDSCs. Herein, I will describe the origin of these MDSCs, the mechanisms of MDSC action during tissue repair, and finally the development of therapeutic strategies to improve regeneration and repair of musculoskeletal tissues. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 9999:1-9, 2018. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

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.

Stem Cell Banking for Regenerative and Personalized Medicine

PubMed Central

Harris, David T.

2014-01-01

Regenerative medicine, tissue engineering and gene therapy offer the opportunity to treat and cure many of today’s intractable afflictions. These approaches to personalized medicine often utilize stem cells to accomplish these goals. However, stem cells can be negatively affected by donor variables such as age and health status at the time of collection, compromising their efficacy. Stem cell banking offers the opportunity to cryogenically preserve stem cells at their most potent state for later use in these applications. Practical stem cell sources include bone marrow, umbilical cord blood and tissue, and adipose tissue. Each of these sources contains stem cells that can be obtained from most individuals, without too much difficulty and in an economical fashion. This review will discuss the advantages and disadvantages of each stem cell source, factors to be considered when contemplating banking each stem cell source, the methodology required to bank each stem cell source, and finally, current and future clinical uses of each stem cell source. PMID:28548060

Stem cell plasticity enables hair regeneration following Lgr5+ cell loss.

PubMed

Hoeck, Joerg D; Biehs, Brian; Kurtova, Antonina V; Kljavin, Noelyn M; de Sousa E Melo, Felipe; Alicke, Bruno; Koeppen, Hartmut; Modrusan, Zora; Piskol, Robert; de Sauvage, Frederic J

2017-06-01

Under injury conditions, dedicated stem cell populations govern tissue regeneration. However, the molecular mechanisms that induce stem cell regeneration and enable plasticity are poorly understood. Here, we investigate stem cell recovery in the context of the hair follicle to understand how two molecularly distinct stem cell populations are integrated. Utilizing diphtheria-toxin-mediated cell ablation of Lgr5 + (leucine-rich repeat-containing G-protein-coupled receptor 5) stem cells, we show that killing of Lgr5 + cells in mice abrogates hair regeneration but this is reversible. During recovery, CD34 + (CD34 antigen) stem cells activate inflammatory response programs and start dividing. Pharmacological attenuation of inflammation inhibits CD34 + cell proliferation. Subsequently, the Wnt pathway controls the recovery of Lgr5 + cells and inhibition of Wnt signalling prevents Lgr5 + cell and hair germ recovery. Thus, our study uncovers a compensatory relationship between two stem cell populations and the underlying molecular mechanisms that enable hair follicle regeneration.

When nano meets stem: the impact of nanotechnology in stem cell biology.

PubMed

Kaur, Savneet; Singhal, Barkha

2012-01-01

Nanotechnology and biomedical treatments using stem cells are among the latest conduits of biotechnological research. Even more recently, scientists have begun finding ways to mate these two specialties of science. The advent of nanotechnology has paved the way for an explicit understanding of stem cell therapy in vivo and by recapitulation of such in vivo environments in the culture, this technology seems to accommodate a great potential in providing new vistas to stem cell research. Nanotechnology carries in its wake, the development of highly stable, efficient and specific gene delivery systems for both in vitro and in vivo genetic engineering of stem cells, use of nanoscale systems (such as microarrays) for investigation of gene expression in stem cells, creation of dynamic three-dimensional nano-environments for in vitro and in vivo maintenance and differentiation of stem cells and development of extremely sensitive in vivo detection systems to gain insights into the mechanisms of stem cell differentiation and apoptosis in different disease models. The present review presents an overview of the current applications and future prospects for the use of nanotechnology in stem cell biology. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Stem cell applications in military medicine.

PubMed

Christopherson, Gregory T; Nesti, Leon J

2011-10-19

There are many similarities between health issues affecting military and civilian patient populations, with the exception of the relatively small but vital segment of active soldiers who experience high-energy blast injuries during combat. A rising incidence of major injuries from explosive devices in recent campaigns has further complicated treatment and recovery, highlighting the need for tissue regenerative options and intensifying interest in the possible role of stem cells for military medicine. In this review we outline the array of tissue-specific injuries typically seen in modern combat - as well as address a few complications unique to soldiers--and discuss the state of current stem cell research in addressing each area. Embryonic, induced-pluripotent and adult stem cell sources are defined, along with advantages and disadvantages unique to each cell type. More detailed stem cell sources are described in the context of each tissue of interest, including neural, cardiopulmonary, musculoskeletal and sensory tissues, with brief discussion of their potential role in regenerative medicine moving forward. Additional commentary is given to military stem cell applications aside from regenerative medicine, such as blood pharming, immunomodulation and drug screening, with an overview of stem cell banking and the unique opportunity provided by the military and civilian overlap of stem cell research.

Efficient femtosecond driven SOX 17 delivery into mouse embryonic stem cells: differentiation studies

NASA Astrophysics Data System (ADS)

Thobakgale, Lebogang; Manoto, Sello Lebohang; Lemboumba, Satuurnin Ombinda; Maaza, Malik; Mthunzi-Kufa, Patience

2017-02-01

Embryonic stem cells have great promise in regenerative medicine because of their ability to self-renew and differentiate into various cell types. Delivery of therapeutic genes into cells has already been achieved using of chemical agents and viral vectors with high transfection efficiencies. However, these methods have also been documented as toxic and in the latter case they can cause latent cell infections. In this study we use femtosecond laser pulses to optically deliver genetic material in mouse embryonic stem cells. Femtosecond laser pulses in contrast to the conventional approach, minimises the risk of unwanted side effects because photons are used to create transient pores on the membrane which allow free entry of molecules with no need for delivery agents. Using an Olympus microscope, fluorescence imaging of the samples post irradiation was performed and decreased expression of stage specific embryonic antigen one (SSEA-1) consistent with on-going cellular differentiation was observed. Our results also show that femtosecond laser pulses were effective in delivering SOX 17 plasmid DNA (pSOX17) which resulted in the differentiation of mouse embryonic stem cells into endoderm cells. We thus concluded that laser transfection of stem cells for the purpose of differentiation, holds potential for applications in tissue engineering as a method of generating new cell lines.

Embryonic stem cells: testing the germ-cell theory.

PubMed

Hochedlinger, Konrad

2011-10-25

The exact cellular origin of embryonic stem cells remains elusive. Now a new study provides compelling evidence that embryonic stem cells, established under conventional culture conditions, originate from a transient germ-cell state. Copyright © 2011 Elsevier Ltd. All rights reserved.

Kidney regeneration and stem cells.

PubMed

Takaori, Koji; Yanagita, Motoko

2014-01-01

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

Xenografts in zebrafish embryos as a rapid functional assay for breast cancer stem-like cell identification.

PubMed

Eguiara, Arrate; Holgado, Olaia; Beloqui, Izaskun; Abalde, Leire; Sanchez, Yolanda; Callol, Carles; Martin, Angel G

2011-11-01

The cancer stem cell is defined by its capacity to self-renew, the potential to differentiate into all cells of the tumor and the ability to proliferate and drive the expansion of the tumor. Thus, targeting these cells may provide novel anti-cancer treatment strategies. Breast cancer stem cells have been isolated according to surface marker expression, ability to efflux fluorescent dyes, increased activity of aldehyde dehydrogenase or the capacity to form spheres in non-adherent culture conditions. In order to test novel drugs directed towards modulating self-renewal of cancer stem cells, rapid, easy and inexpensive assays must be developed. Using 2 days-post-fertilization (dpf) zebrafish embryos as transplant recipients, we show that cells grown in mammospheres from breast carcinoma cell lines migrate to the tail of the embryo and form masses with a significantly higher frequency than parental monolayer populations. When stem-like self-renewal was targeted in the parental population by the use of the dietary supplement curcumin, cell migration and mass formation were reduced, indicating that these effects were associated with stem-like cell content. This is a proof of principle report that proposes a rapid and inexpensive assay to target in vivo cancer stem-like cells, which may be used to unravel basic cancer stem cell biology and for drug screening.

In search of adult renal stem cells.

PubMed

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

2004-01-01

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

Bone regeneration and stem cells