共查询到20条相似文献，搜索用时 15 毫秒
1.
Yoshimura Y 《Human cell》2006,19(2):83-86
The birth announced in 1997 of Dolly, the lamb cloned from the somatic mammary cells of an adult ewe, and the discovery of human embryonic stem cells in 1998 have been the most exciting developments in the biological sciences in the past decade. Reproductive somatic cell nuclear transfer (SCNT) in additional species has been inefficient in that relatively few births, harmful side effects and high fetal and neonatal death rates have resulted from many attempts. Ongoing debates about the ethics of reproductive SCNT have revealed that some researchers regard human reproductive SCNT as morally unacceptable in all circumstances, others see merit in reproductive SCNT in certain circumstances and others await more information before making judgment about the ethical status of the procedure. Regenerative medicine and emerging biotechnologies started to revolutionize the practice of medicine. Advances in stem cell biology, including embryonic and postnatal somatic stem cells, have made the prospect of tissue regeneration a potential reality. Mammal cloning experiments have provided new impetus to the prospect of regenerative medicine through stem cell research. The procedure of SCNT could be used to create the raw material to replace defective or senescent tissue as a natural extension of the biology of stem cells. Researchers working in reproductive medicine should consider the potential hope given to many patients against the requisite and ethically contentious creation of human blastocysts for therapeutic intent. 相似文献
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Anja Buchheiser Stefanie Liedtke Leendert H.J. Looijenga Gesine Kögler 《Journal of cellular biochemistry》2009,108(4):762-768
Umbilical cord blood (CB) has become a commonly accepted source of hematopoietic stem cells for transplantation in children and adults. It is readily available and outperforms bone marrow (BM) as well as peripheral blood stem cells in terms of tolerance for HLA‐mismatches between donor and recipient and its decreased graft‐versus‐host disease. Clinical use has been expanded from hematological malignancies to various areas such as treatment of metabolic genetic disorders or to induce angiogenesis. For the last years CB has been under intense experimental investigation in in vitro differentiation models as well as in preclinical animal models. Since CB‐derived stem cells offer multiple advantages over adult stem cells from other sources like BM, CB may provide a future source of stem cells for tissue repair and regeneration. To facilitate the use of CB‐derived stem cells in clinical scenarios, the biology of these cells needs to be further explored in detail particularly with regard to the fact that different non‐hematopoietic stem cell populations occur within CB. Here we explore the most consistent and the most contradictory data referring to the differentiation potential of CB‐derived stem cells and give an outlook on their potential clinical value including and possible reprogramming into IPS cells. J. Cell. Biochem. 108: 762–768, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
3.
Douglas Sipp 《Developing world bioethics》2017,17(3):167-172
The commercial provision of putative stem cell‐based medical interventions in the absence of conclusive evidence of safety and efficacy has formed the basis of an unregulated industry for more than a decade. Many clinics offering such supposed stem cell treatments include statements about the ‘ethical’ nature of somatic (often colloquially referred to as ‘adult’ stem cells) stem cells, in specific contrast to human embryonic stem cells (hESCs), which have been the subject of intensive political, legal, and religious controversy since their first derivation in 1998 1 . Christian groups—both Roman Catholic and evangelical Protestant—in many countries have explicitly promoted the medical potential and current‐day successes in the clinical application of somatic stem cells, lending indirect support to the activities of businesses marketing stem cells ahead of evidence 2 . In this article, I make a preliminary examination of how the structures and belief systems of certain churches in South Korea and the United States, both of which are home to significant stem cell marketing industries, has complemented other factors, including national biomedical funding initiatives, international economic rivalries, permissive legal structures, which have lent impetus to a problematic and often exploitative sector of biomedical commerce 3 . 相似文献
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Qingsong Ye Tzu&#x;Cheng Sung Jen&#x;Ming Yang Qing&#x;Dong Ling Yan He Akon Higuchi 《Cell proliferation》2020,53(12)
There is a need to store very large numbers of conventional human pluripotent stem cell (hPSC) lines for their off‐the‐shelf usage in stem cell therapy. Therefore, it is valuable to generate “universal” or “hypoimmunogenic” hPSCs with gene‐editing technology by knocking out or in immune‐related genes. A few universal or hypoimmunogenic hPSC lines should be enough to store for their off‐the‐shelf usage. Here, we overview and discuss how to prepare universal or hypoimmunogenic hPSCs and their disadvantages. β2‐Microglobulin‐knockout hPSCs did not harbour human leukocyte antigen (HLA)‐expressing class I cells but rather activated natural killer (NK) cells. To avoid NK cell and macrophage activities, homozygous hPSCs expressing a single allele of an HLA class I molecule, such as HLA‐C, were developed. Major HLA class I molecules were knocked out, and PD‐L1, HLA‐G and CD47 were knocked in hPSCs using CRISPR/Cas9 gene editing. These cells escaped activation of not only T cells but also NK cells and macrophages, generating universal hPSCs. 相似文献
5.
Coleman CM 《Birth defects research. Part C, Embryo today : reviews》2008,84(3):245-256
Although the chick embryo, including its extraembryonic membranes, has long been used as a model for developmental biology, its potential as a model for the repair and regeneration of adult human tissues is often overlooked. The chick offers a well-defined profile of intercellular and intracellular signaling pathways regulating the development of nearly every organ system in conjunction with great flexibility for chimeric and transgenic experiments. Depending upon the system of interest, the chick can either directly reflect the human condition, as in spinal cord repair or in chorioallantoic membrane wound healing, and therefore act as an in vivo model for repair, or mirror our aspired therapy as in limb generation or otic restoration and therefore act as our guide. With these unique opportunities, the chick embryo is certainly a model to be considered when aiming to develop a regenerative therapy for human applications. 相似文献
6.
Rafael G. Ruiz Jose M. C. Rosell Gabriele Ceccarelli Ciro De Sio Gabriella C. De Angelis Hernan Pinto Carlo Astarita Antonio Graziano 《Journal of cellular physiology》2020,235(5):4587-4593
Regenerative medicine is a multidisciplinary field that combines engineering and life science principles to promote regeneration, potentially restoring the physiological condition in diseased tissues. Specifically, the developments of complex grafts enhance the intrinsic regenerative capacity of the host by altering its environment. Autologous micrografts obtained through Rigenera® micrografting technology are able to promote derma and bone regeneration. Androgenetic alopecia (AGA) leads to a progressive thinning of scalp hair affecting 60–70% of the adult population worldwide. Pharmacological treatment offers moderate results and hair transplantation represents the only permanent treatment option. The aim of this study was to demonstrate the role of dermis micrografting in the treatment of AGA by clinical and histological evaluations after 4, 6, and 12 months. Hair growth and density were improved at all indicated times. Those outcomes were also confirmed by the TrichoScan® analysis, reporting an increase of total hair count and density with an increase and reduction of anagen and telogen phases, respectively. Scalp dermoscopic analysis showed an improvement of hair density and histological analysis indicated a clear amelioration of the scalp, development of hair follicles, and a beginning of cuticle formation. Collectively, those results suggest a possible use of the micrografts as a novel therapeutic option in the management of AGA. 相似文献
7.
Epigenetic reprogramming provides valuable resources for customized pluripotent stem cells generation, which are thought to be important bases of future regenerative medicine. Here we review the commonly used methods for epigenetic reprogramming: somatic cell nuclear transfer, cell fusion, cell extract treatment, inducing pluripotency by defined molecules, and briefly discuss their advantages and limitations. Finally we propose that mechanisms underlying epigenetic reprogramming and safety evaluation platform will be future research directions. 相似文献
8.
J. Wardale L. Mullen D. Howard S. Ghose N. Rushton 《Cell biochemistry and function》2015,33(5):277-284
Biomimetic scaffolds hold great promise for therapeutic repair of cartilage, but although most scaffolds are tested with cells in vitro, there are very few ex vivo models (EVMs) where adult cartilage and scaffolds are co‐cultured to optimize their interaction prior to in vivo studies. This study describes a simple, non‐compressive method that is applicable to mammalian or human cartilage and provides a reasonable throughput of samples. Rings of full‐depth articular cartilage slices were derived from human donors undergoing knee replacement for osteoarthritis and a 3 mm core of a collagen/glycosaminoglycan biomimetic scaffold (Tigenix, UK) inserted to create the EVM. Adult osteoarthritis chondrocytes were seeded into the scaffold and cultures maintained for up to 30 days. Ex vivo models were stable throughout experiments, and cells remained viable. Chondrocytes seeded into the EVM attached throughout the scaffold and in contact with the cartilage explants. Cell migration and deposition of extracellular matrix proteins in the scaffold was enhanced by growth factors particularly if the scaffold was preloaded with growth factors. This study demonstrates that the EVM represents a suitable model that has potential for testing a range of therapeutic parameters such as numbers/types of cell, growth factors or therapeutic drugs before progressing to costly pre‐clinical trials. © 2015 The Authors. Cell Biochemistry and Function Published by John Wiley & Sons Ltd. 相似文献
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Paul Whiting Julie Kerby Peter Coffey Lyndon da Cruz Ruth McKernan 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1680)
Since the first publication of the derivation of human embryonic stem cells in 1998, there has been hope and expectation that this technology will lead to a wave of regenerative medicine therapies with the potential to revolutionize our approach to managing certain diseases. Despite significant resources in this direction, the path to the clinic for an embryonic stem-cell-based regenerative medicine therapy has not proven straightforward, though in the past few years progress has been made. Here, with a focus upon retinal disease, we discuss the current status of the development of such therapies. We also highlight some of our own experiences of progressing a retinal pigment epithelium cell replacement therapy towards the clinic. 相似文献
12.
Regenerative medicine is a burgeoning field that is important to combat challenging diseases and functional impairments. Compared with traditional cell therapies with evident shortcomings (e.g., cell suspension injection or tissue engineering with scaffolds), scaffold-free cell sheet technology enables transplanted cells to be grafted and fully maintain their viability on target sites. Clinical and experimental studies have advanced the application of cell sheet technology to numerous tissues and organs (e.g., liver, cornea and bone). However, previous reviews have failed to discuss vital aspects of this rapidly developing technology, and many new challenges are gradually emerging. This review aims to provide a comprehensive introduction to cell sheet technology from cell selection to the ultimate applications of cell sheets, and challenges and future visions are also described. 相似文献
13.
Caren E. Petrie Aronin Rocky S. Tuan 《Birth defects research. Part C, Embryo today : reviews》2010,90(1):67-74
Adult mesenchymal stem cells (MSCs) include a select population of resident cells within adult tissues, which retain the ability to differentiate along several tissue‐specific lineages under defined media conditions and have finite expansion potential in vitro. These adult progenitor populations have been identified in various tissues, but it remains unclear exactly what role both transplanted and native MSCs play in processes of disease and regeneration. Interestingly, increasing evidence reveals a unique antiinflammatory immunomodulatory phenotype shared among this population, lending support to the idea that MSCs play a central role in early tissue remodeling responses where a controlled inflammatory response is required. However, additional evidence suggests that MSCs may not retain infinite immune privilege and that the context with which these cells are introduced in vivo may influence their immune phenotype. Therefore, understanding this dynamic microenvironment in which MSCs participate in complex feedback loops acting upon and being influenced by a plethora of secreted cytokines, extracellular matrix molecules, and fragments will be critical to elucidating the role of MSCs in the intertwined processes of immunomodulation and tissue repair. Birth Defects Research (Part C) 90:67–74, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
14.
脱细胞基质(decellularized extracellular matrix, dECM)旨在去除引起免疫排斥的细胞,保留原组织结构和成分。由于其具有与原组织器官相似的结构和成分,在组织工程和生物医学的应用上受到广泛关注,已成为一种很有前景的生物医学材料。通过适当的脱细胞方法,dECM很容易能够从组织器官中获得。文中总结了脱细胞的方法及最新研究进展,同时对脱细胞后支架灭菌、交联和保存的方式进行综述,概括了不同组织器官获得的脱细胞支架的最新应用及进展。最后对脱细胞支架目前面临的问题和挑战进行分析,并展望了未来的发展趋势。 相似文献
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Yuka Yamauchi Isao Hirata Kotaro Tanimoto Koichi Kato 《Biotechnology and bioengineering》2020,117(9):2741-2748
Neural progenitor cells (NPCs) are considered to be a promising source for stem cell-based regenerative therapy for central nervous disorders. However, the widespread clinical application of NPCs requires another technology that permits the efficient production of pure NPCs in large quantities. In this study, culture substrates were designed by immobilizing epidermal growth factor (EGF) onto the substrate and evaluated for their feasibility of expanding NPCs obtained through the neurosphere culture of induced pluripotent stem (iPS) cells. After three passages we obtained neurospheres that contained cells abundantly expressing an EGF receptor. The neurospheres were dissociated into single cells and seeded onto the EGF-immobilized substrates. It was observed that neurosphere-forming cells seeded and cultured on the EGF-immobilized surface formed a two-dimensional cellular network characteristic of NPCs. These cells were found to be capable of being subcultured, while remaining their proliferation potential. Furthermore, a majority of cells (~99% of total cells) on the substrate was shown to express an NPC marker, nestin, whereas a limited number of cells (~1% of total cells) expressed neuronal marker, β-tubulin III. These results as a whole demonstrate that the EGF-immobilized substrate allows for iPS cell-derived NPCs to efficiently proliferate while maintaining the undifferentiated state. 相似文献
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Sanshiro Kanazawa Satoru Nishizawa Tsuyoshi Takato Kazuto Hoshi 《Journal of cellular physiology》2017,232(11):3182-3193
18.
Alann Thaffarell Portilho Souza Gileade Pereira Freitas Helena Bacha Lopes Emanuela Prado Ferraz Fabiola Singaretti Oliveira Marcio Mateus Beloti Adalberto Luiz Rosa 《Cytotherapy》2018,20(10):1267-1277
Background aims
Regenerative medicine strategies based on cell therapy are considered a promising approach to repair bone defects. The aims of this study were to evaluate the effect of subculturing on the osteogenic potential of osteoblasts derived from newborn rat calvaria and the effect of these osteoblasts on bone repair of rat calvaria defects.Methods
Cells were obtained from 50 newborn rat calvaria, and primary osteoblasts (OB) were compared with first passage (OB-P1) in terms of osteogenic potential by assaying cell proliferation, alkaline phosphatase (ALP) activity, extracellular matrix mineralization and gene expression of the osteoblastic markers RUNX2, ALP, osteocalcin and bone sialoprotein. Then, 5-mm calvaria defects were created in 24 Wistar rats, and after 2 weeks, they were locally injected with 50 µL of phosphate-buffered saline containing either 5?×?106 osteoblasts (OB-P1, n?=?12) or no cells (control, n?=?12). Four weeks post-injection, the bone formation was evaluated by micro-computed tomography and histological analyses. Data were compared by analysis of variance, followed by the Student-Newman-Keuls's test or Student's t-test (P ≤ 0.05).Results
OB-P1 showed high proliferation and ALP activity, and despite the reduced gene expression of osteoblastic markers and extracellular matrix mineralization compared with OB, they displayed osteogenic potential, being a good choice for injection into calvaria defects. The micro-tomographic and histological data showed that defects treated with OB-P1 presented higher bone formation compared with control defects.Discussion
Our results indicate that cells derived from newborn rat calvaria retain osteoblastic characteristics after subculturing and that these osteoblasts stimulate bone repair in a rat calvaria defect model. 相似文献19.
A wide range of biomaterials and tissue‐engineered scaffolds are being investigated to support and stimulate bone healing in animal models. Using phantoms and rat cadavers, we investigated the feasibility of using spatially offset Raman spectroscopy (SORS) to monitor changes in collagen concentration at levels similar to those expected to occur in vivo during bone regeneration (0‐0.84 g/cm3). A partial least squares (PLS) regression model was developed to quantify collagen concentration in plugs consisting of mixtures or collagen and hydroxyapatite (predictive power of ±0.16 g/cm3). The PLS model was then applied on SORS spectra acquired from rat cadavers after implanting the collagen: hydroxyapatite plugs in drilled skull defects. The PLS model successfully predicting the profile of collagen concentration, but with an increased predictive error of ±0.30 g/cm3. These results demonstrate the potential of SORS to quantify collagen concentrations, in the range relevant to those occurring during new bone formation. 相似文献
20.
Duško Spasovski Vesna Spasovski Zoran Baščarević Maja Stojiljković Miša Vreća Marina Anđelković Sonja Pavlović 《The journal of gene medicine》2018,20(1)