|  |  |  | | | | | TE-RegenMed-StemCell feed | | | | | | | | | | | | | | | | | | | Adipose-derived stem cells for skin regeneration. Methods Mol Biol. 2011;702:453-9 Authors: Mizuno H, Nambu M Intractable skin ulcers resulting from diabetes, ischemia and collagen diseases represent significant problems with few solutions. Cell-based therapy may hold promise in overcoming such disorders. In order to establish a suitable experimental model for the treatment of such ulcers using stem cells, this chapter describes detailed methods for: (1) isolation of stem cells from adipose tissue, termed adipose-derived stem cells (ASCs), (2) preparing a hybrid-type artificial dermis that consists of a type I collagen sponge and ASCs, (3) preparing intractable ulcers using Mitomycin C, and (4) evaluating the effect of wound healing histologically. ASCs seeded onto a type I collagen sponge are applied to intractable ulcers induced by topical application of Mitomycin C. Histological evaluation after 1 and 2 weeks revealed an increase in capillary density and granulation thickness of the hybrid-type artificial dermis. These findings suggest that ASCs may have a positive effect on wound healing and may be a useful tool for future cell-based therapy. PMID: 21082422 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Differentiation of adipose-derived stem cells for tendon repair. Methods Mol Biol. 2011;702:443-51 Authors: Uysal AC, Mizuno H The goal of primary tendon repair is to increase tensile strength at the time of mobilization. Tendon repair and regeneration using mesenchymal stem cells have been described in several studies; however, the use of adipose derived stem cells (ASCs) for tendon repair has only recently been considered. In order to establish a suitable experimental model for the primary tendon repair using ASCs, this chapter describes the detailed methods for: (1) isolating stem cells from adipose tissue, (2) generation of a primary tendon injury and repair model, (3) evaluating functional restoration by measuring tensile strength, and (4) investigating the mechanisms involved in ASC-mediated tendon healing by histological and immunohistochemical analyses. Topical administration of ASCs to the site of injury accelerates tendon repair, as exhibited by a significant increase in tensile strength, direct differentiation of ASCs toward tenocytes and endothelial cells, and increases in angiogenic growth factors. These findings suggest that ASCs may have a positive effect on primary tendon repair and may be useful for future cell-based therapy. PMID: 21082421 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Neural differentiation of human adipose tissue-derived stem cells. Methods Mol Biol. 2011;702:219-31 Authors: Yu JM, Bunnell BA, Kang SK While adult stem cells can be induced to transdifferentiate into multiple lineages of cells or tissues, their plasticity and utility for human therapy remains controversial. In this chapter, we describe methods for the transdifferentiation of human adipose tissue-derived stem cells (ASCs) along neural lineages using in vitro and in vivo systems. The in vitro neural differentiation of ASCs has been reported by several groups using serum-free cytokine induction, butylated hydroxyanisole (BHA) chemical induction, and neurosphere formation in combination with the cytokines, such as brain-derived neurotrophic factor (BDNF) and basic fibroblast growth factor (bFGF). For in vivo neurogenic induction, ASCs are treated with BDNF and bFGF to form neurospheres in vitro and then delivered directly to the brain. In this chapter, several detailed protocols for the effective neurogenic induction of ASCs in vitro and in vivo are described. The protocols described herein can be applied to further molecular and mechanistic studies of neurogenic induction and differentiation of ASCs. In addition, these methods can be useful for differentiating ASCs for therapeutic intervention in central nervous system disorders. PMID: 21082405 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Adipose-derived stem cells for periodontal tissue regeneration. Methods Mol Biol. 2011;702:461-70 Authors: Tobita M, Mizuno H Mesenchymal stem cells can effectively regenerate destroyed periodontal tissue. Because periodontal tissues are complex, mesenchymal stem cells that can differentiate into many tissue types would aid periodontal tissue regeneration. Indeed, periodontal tissue regeneration using mesenchymal stem cells derived from adipose tissue or bone marrow has been performed in experimental animal models, such as rat, canine, swine, and monkey. We have shown that rat periodontal tissue can be regenerated with adipose-derived stem cells. Adipose tissue contains a large number of stromal cells and is relatively easy to obtain in large quantities, and thus constitutes a very convenient stromal cell source. In this chapter, we introduce a rat periodontal tissue regeneration model using adipose-derived stem cells. PMID: 21082423 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Evaluation of Biomimetic Scaffold of Gelatin-Hydroxyapatite Crosslink as a Novel Scaffold for Tissue Engineering: Biocompatibility Evaluation with Human PDL Fibroblasts, Human Mesenchymal Stromal Cells, and Primary Bone Cells. J Biomater Appl. 2011 Feb 22; Authors: Rungsiyanont S, Dhanesuan N, Swasdison S, Kasugai S Biomimetic gelatin (gel)-hydroxyapatite (HA) composites have been prepared for studying hard tissue engineering scaffolds. However, the biocompatibility test of this form of material using these three cell types, which are periodontal ligament (PDL) fibroblast cells, human mesenchymal stromal cells (HMSc) and primary cells from human hip bone (HBc) has never been evaluated. The objective of this article is to prepare and evaluate the biocompatibility of gel-HA crosslinked scaffold for tissue engineering. Two different scaffolds were prepared: preparation (1), 2.5% gel/2.5% HA; preparation (2), 2.5% gel/5% HA. Three cell types including PDL, HMSc, and HBc were used. Assessment of biocompatibility and osteoblastic cellular responses was evaluated using a three-dimensional cell culture method and scanning electron microscopy (SEM). From SEM, it was observed that scaffold (1) exhibits stable porous formation with well-blended and dispersed HA powder. All three cell types were able to proliferate in both scaffolds. The HMSc and HBc got attached to the scaffolds to a significantly higher degree and subsequently proliferated more than PDL. The alkaline phosphatase (ALP) activities of HMSc and HBc were stronger when cultured in scaffold (S1) than (S2). It was seen that the two scaffold preparations show good biocompatibility with all three cell types tested. The better cellular responses with scaffold (S1) than (S2) might be due to the different structural and morphological characteristics, that is, scaffold (S1) retained more small-sized apatite crystals and a better developed pore configuration than scaffold (S2). Based on these findings, the biomimetically synthesized composite scaffolds have the potential to be used in hard tissue regeneration and tissue engineering fields. PMID: 21343214 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Physical Stimulation of Chondrogenic Cells In Vitro: A Review. Clin Orthop Relat Res. 2011 Feb 23; Authors: Grad S, Eglin D, Alini M, Stoddart MJ BACKGROUND: Mechanical stimuli are of crucial importance for the development and maintenance of articular cartilage. For conditioning of cartilaginous tissues, various bioreactor systems have been developed that have mainly aimed to produce cartilaginous grafts for tissue engineering applications. Emphasis has been on in vitro preconditioning, whereas the same devices could be used to attempt to predict the response of the cells in vivo or as a prescreening method before animal studies. As a result of the complexity of the load and motion patterns within an articulating joint, no bioreactor can completely recreate the in vivo situation. QUESTIONS/PURPOSES: This article aims to classify the various loading bioreactors into logical categories, highlight the response of mesenchymal stem cells and chondrocytes to the various stimuli applied, and determine which data could be used within a clinical setting. METHODS: We performed a Medline search using specific search terms, then selectively reviewed relevant research relating to physical stimulation of chondrogenic cells in vitro, focusing on cellular responses to the specific load applied. RESULTS: There is much data pertaining to increases in chondrogenic gene expression as a result of controlled loading protocols. Uniaxial loading leads to selective upregulation of genes normally associated with a chondrogenic phenotype, whereas multiaxial loading results in a broader pattern of chondrogenic gene upregulation. The potential for the body to be used as an in vivo bioreactor is being increasingly explored. CONCLUSIONS: Bioreactors are important tools for understanding the potential response of chondrogenic cells within the joint environment. However, to replicate the natural in vivo situation, more complex motion patterns are required to induce more physiological chondrogenic gene upregulation. PMID: 21344272 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | [The treatment of focal chondral lesions of the knee]. Harefuah. 2010 Aug;149(8):542-6, 549 Authors: Khashan M, Chechik O, Arbel R, Morag G Focal osteochondral lesions of the knee are a common cause of pain and other knee symptoms, and are mostly caused by traumatic injuries. The spontaneous repair ability of the articular cartilage tissue is very limited. Thus, focal chondral lesions result in early degenerative changes and post-traumatic osteoarthritis. The surgical treatment of focal osteochondral lesions can be divided into three major groups: cartilage debridement techniques, marrow stimulating techniques and transplantation techniques. Lesion debridement causes limited and temporary symptoms relief. While marrow stimulating techniques are considered simple, cheap and easy to perform, some of the transplantation techniques are complicated and consist of highly demanding surgery and new technologies of tissue engineering. Many published studies attempted to evaluate the efficacy of the treatment methods and to compare between them. There is no obvious or definite advantage of any one technique. There are relative advantages of some techniques according to the lesion size and patient's factors. Yet, among the current available treatment options none was found to produce hyaline cartilage consistently. In order to improve the current treatment and to find new treatment techniques, significant advances were achieved in the research of stem cells, scaffolds and growth factors in the last years. Further advances and more comparative and long term studies, particularly those that evaluate the efficacy of the new treatment techniques are needed. PMID: 21341437 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | VEGF release from alginate microspheres under simulated physiological compressive loading and the effect on human vascular endothelial cells. Tissue Eng Part A. 2011 Feb 22; Authors: Li Q, Hou T, Zhao J, Xu J Bone tissue engineering has generated promising results in bone defect repair, but is limited by the inherently poor nutrient supply to non-vascularized tissue-engineered bone grafts. In this study, we investigated the delivery of vascular endothelial growth factor (VEGF) and the effect on in vitro cultured human umbilical vein endothelial cells (HUVECs), in an attempt to provide experimental basis for promoting the vascularization of tissue-engineered bone grafts. A mechanical stimulator was developed to generate a periodic compressive load analogous to goat locomotor characteristics, simulating the mechanical stimulation applied on the fracture ends of the load-bearing bone. Poly-L-lysine-coated VEGF/alginate microspheres were combined with demineralized bone matrices into composites, and the in vitro release of VEGF from these composites was evaluated under periodic compression. The effect of the release media on human umbilical vein endothelial cells (HUVECs) was also investigated. Compression slightly accelerated VEGF release at the early stage (< 11 d) compared to non-compressed composites, although the release profiles of the two composite groups were generally similar. The released VEGF promoted HUVECs proliferation. In addition, the periodic compression applied on composites containing both HUVECs and VEGF/alginate microspheres promoted the expression of matrix metalloproteinases-2/9 (MMP-2/9) in HUVECs. This study provides a model for investigating VEGF release under simulated in vivo biomechanical conditions and without the disadvantage of the rapid degradation of VEGF in in vivo investigation of VEGF release. The results also provide important guidelines for future in vivo experiments. PMID: 21341993 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | EVALUATION OF SCAFFOLDS BASED ON ¿-TRICALCIUM PHOSPHATE CEMENTS FOR TISSUE ENGINEERING APPLICATION. IEEE Trans Biomed Eng. 2011 Feb 22; Authors: Dos Santos L, Machado J, Giehl I, Nardi N Growth of cells in three-dimensional porous scaffolds has gained importance in the field of tissue engineering. The scaffolds guide cellular growth, synthesize extra-cellular matrix and other biological molecules, and make the formation of tissues and functional organs easier. The aim of this work was to use á-TCP (á-tricalcium phosphate) cement in order to obtain new types of scaffolds with the aid of paraffin spheres as pore generators. The porosity of the scaffolds produced with paraffin spheres was analyzed and compared to the literature, and the study of scaffold permeability using the Forchenheimer equation allowed the analysis of pore interconnectivity. In vitro tests showed the behavior of scaffolds in solutions of SBF (Simulated Body Fluid), and viability and cell proliferation were also evaluated. The results show the potential use of the materials developed for scaffolds for use in tissue engineering applications. PMID: 21342838 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Three-dimensional culture and bioreactors for cellular therapies. Cytotherapy. 2011 Feb 22; Authors: Naing MW, Williams DJ Abstract A bioreactor is defined as a specifically designed vessel to facilitate the growth of organisms and cells through application of physical and/or electrical stimulus. When cells with therapeutic potential were first discovered, they were initially cultured and expanded in two-dimensional (2-D) culture vessels such as plates or T-flasks. However, it was soon discovered that bioreactors could be used to expand and maintain cultures more easily and efficiently. Since then, bioreactors have come to be accepted as an indispensable tool to advance cell and tissue culture further. A wide array of bioreactors has been developed to date, and in recent years businesses have started supplying bioreactors commercially. Bioreactors in the research arena range from stirred tank bioreactors for suspension culture to those with various mechanical actuators that can apply different fluidic and mechanical stresses to tissues and three-dimensional (3-D) scaffolds. As regenerative medicine gains more traction in the clinic, bioreactors for use with cellular therapies are being developed and marketed. While many of the simpler bioreactors are fit for purpose, others fail to satisfy the complex requirements of tissues in culture. We have examined the use of different types of bioreactors in regenerative medicine and evaluated the application of bioreactors in the realization of emerging cellular therapies. PMID: 21341974 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Adipose-derived stem cells for skin regeneration. Methods Mol Biol. 2011;702:453-9 Authors: Mizuno H, Nambu M Intractable skin ulcers resulting from diabetes, ischemia and collagen diseases represent significant problems with few solutions. Cell-based therapy may hold promise in overcoming such disorders. In order to establish a suitable experimental model for the treatment of such ulcers using stem cells, this chapter describes detailed methods for: (1) isolation of stem cells from adipose tissue, termed adipose-derived stem cells (ASCs), (2) preparing a hybrid-type artificial dermis that consists of a type I collagen sponge and ASCs, (3) preparing intractable ulcers using Mitomycin C, and (4) evaluating the effect of wound healing histologically. ASCs seeded onto a type I collagen sponge are applied to intractable ulcers induced by topical application of Mitomycin C. Histological evaluation after 1 and 2 weeks revealed an increase in capillary density and granulation thickness of the hybrid-type artificial dermis. These findings suggest that ASCs may have a positive effect on wound healing and may be a useful tool for future cell-based therapy. PMID: 21082422 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Embryonic origin of the adult hematopoietic system: advances and questions. Development. 2011 Mar;138(6):1017-31 Authors: Medvinsky A, Rybtsov S, Taoudi S Definitive hematopoietic stem cells (HSCs) lie at the foundation of the adult hematopoietic system and provide an organism throughout its life with all blood cell types. Several tissues demonstrate hematopoietic activity at early stages of embryonic development, but which tissue is the primary source of these important cells and what are the early embryonic ancestors of definitive HSCs? Here, we review recent advances in the field of HSC research that have shed light on such questions, while setting them into a historical context, and discuss key issues currently circulating in this field. PMID: 21343360 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Stem Cells Therapies in Basic Science and Translational Medicine: Current Status and Treatment Monitoring Strategies. Curr Pharm Biotechnol. 2011 Feb 21; Authors: Banerjee C Stem-cell technology is a major area within cell therapy that promises significant therapeutic outcome. The plasticity and self-renewal capabilities of stem cells make them valuable tools for potential application in regenerative medicine and tissue replacement following injury or disease. Here, we discuss the different types of stem cells currently used in research, preclinical and early clinical development, their potential therapeutic and diagnostic applications, and current barriers to translating basic research into clinical therapies. Biomedical imaging is increasingly being used to monitor the fate of transplanted stem cells, including their survival, proliferation, differentiation and homing to targeted organs and tissues. We discuss different imaging modalities currently utilized to track stem calls, the advantages and challenges, and future implications in clinical applications. PMID: 21342107 [PubMed - as supplied by publisher] | | | | | | | | | |  | |  | |  |
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