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Adipose-derived Stem Cells (adipose-derived + stem_cell)
Selected AbstractsAdipogenic Differentiation of Human Adipose Tissue,Derived Stem Cells Obtained from Cryopreserved Adipose AspiratesDERMATOLOGIC SURGERY, Issue 7 2010JUNG EUN LEE MS BACKGROUND Although frozen adipose tissue is frequently used for soft tissue augmentation, the viability of frozen fat remains a controversy. The cryopreservation of adipose tissue is important for the future use of adipose-derived stem cells (ASCs) and adipocytes. OBJECTIVE To determine whether optimal cryopreservation techniques with regard to the addition of cryopreservative agents and preservation temperature is essential for the long-term storage of adipose tissue and whether ASCs from cryopreserved adipose aspirates are reliable for use in adipogenic differentiation. MATERIALS AND METHODS Adipose tissue was frozen directly or with cryoprotectant at ,20°C or ,80°C for 1 year. The viability of adipose aspirates and the differentiation of ASCs isolated from adipose tissue were evaluated. RESULTS The viability of adipose aspirates frozen with dimethyl sulfoxide at ,80°C was approximately 87% after 2 months of storage. Moreover, ASCs from adipose tissue stored with cryoprotectant survived successfully for 1 year and differentiated into adipocytes, although ASCs were not detected in the directly frozen adipose tissue. CONCLUSION Adipose tissue cryopreserved with cryoprotectant and stored at optimal temperature might prove to be a reliable source of human ASCs and adipocytes. The authors have indicated no significant interest with commercial supporters. [source] The role of stem cells in suppurative environmentsEXPERIMENTAL DERMATOLOGY, Issue 6 2006Dolores Herreros Purpose:,The management of suppurative perianal lesions presents an extremely challenging problem. Stem cells (SC) extracted from certain tissues, such as adipose tissue, can differentiate into various cell types. Therefore, we have tried to use such cells to stimulate healing in a purulent environment. Methods:,In the beginning, we designed a phase I clinical trial, involving five patients with Crohn's disease. We inoculated nine fistulas in four patients with autologous adipose-derived stem cells (ADSC) and were followed at least 8 weeks. Seventy-five percent became healed, and 25% showed a decrease in output flow. No adverse effects were observed in any patient. This study evidenced that such cells are safe. Then, we started a research line using SC in different suppurative environments. During the course of these studies, we had the opportunity to treat a patient with perianal hidradenitis suppurativa using our current protocol of ADSC transplantation. Eight weeks after injection, patient had no perianal suppuration, and a year later remains well. Discussion:,The biological mechanism that underlies the therapeutic success of ADSC transplantation is unknown. Cell differentiation, secretion of growth factors or immunomodulatory effects have been suggested. No ethical conflicts were identified by our Ethics Committee, because the cells were autologous. Conclusions:,Our study shows that ADSC are safe for the treatment of suppurative processes. The actual number of patients included and the uncontrolled nature of these pilot studies do not allow demonstration of the effectiveness of the treatment. However, the results encourage the performance of further studies. [source] Ex vivo organ culture of adipose tissue for in situ mobilization of adipose-derived stem cells and defining the stem cell nicheJOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2010Young-Il Yang In spite of the advances in the knowledge of adipose-derived stem cells (ASCs), in situ location of ASCs and the niche component of adipose tissue (AT) remain controversial due to the lack of an appropriate culture system. Here we describe a fibrin matrix-supported three-dimensional (3D) organ culture system for AT which sustains the ASC niche and allows for in situ mobilization and expansion of ASCs in vitro. AT fragments were completely encapsulated within the fibrin matrix and cultured under dynamic condition. The use of organ culture of AT resulted in a robust outgrowth and proliferation in the fibrin matrix. The outgrown cells were successfully recovered from fibrin by urokinase treatment. These outgrown cells fulfilled the criteria of mesenchymal stem cells, adherence to plastic, multilineage differentiation, and cell surface molecule expression. In vitro label retaining assay revealed that newly divided cells during the culture resided in interstitium between adipocytes and capillary endothelial cells. These interstitial stromal cells proliferated and outgrew into the fibrin matrix. Both in situ mobilized and outgrown cells expressed CD146 and ,-smooth muscle actin (SMA), but no endothelial cell markers (CD31 and CD34). The structural integrity and spatial approximation of CD31,/CD34,/CD146+/SMA+ interstitial stromal cells, adipocytes, and capillary endothelial cells were well preserved during in vitro culture. Our results suggest that ASCs are natively associated with the capillary wall and more specifically, belong to a subset of pericytes. Furthermore, organ culture of AT within a fibrin matrix-supported 3D environment can recapitulate the ASC niche in vitro. J. Cell. Physiol. 224: 807,816, 2010. © 2010 Wiley-Liss, Inc. [source] Transdifferentiation of adipose-derived stem cells into hepatocytes: a new approachLIVER INTERNATIONAL, Issue 6 2010James Lue Abstract Background: Several studies have demonstrated techniques in differentiating human adipose-derived stem cells (hADSCs) into hepatocytes. Unfortunately, transdifferentiation is inefficient, and the function of these induced hepatocyte-like cells (which we termed ,iHeps') is low compared with that of real hepatocytes. Aims: We aimed to identify transcriptional deficiencies in iHeps that are critical to hepatocyte development, which may provide insights into improving the efficiency of transdifferentiation. Methods: hADSCs were differentiated into iHeps, and iHeps were assayed for hepatocyte-like activity. iHeps were then screened for expression of several growth factors, receptors and transcription factors (TFs) critical to liver development using reverse transcription-polymerase chain reaction (RT-PCR). Deficient TFs were transduced into hADSCs and hepatocyte function was reassessed after hepatic differentiation. Results: Differentiation of hADSCs into iHeps resulted in the upregulation of hepatic proteins. However, the levels of expression of hepatocyte-specific proteins in these iHeps were well below those of Huh 7.5 hepatoma cells, used in comparison. Five developmental TFs were notably absent on the RT-PCR screen. Lentiviral transduction of these TFs into hADSCs followed by culture in hepatocyte induction medium resulted in increased albumin expression compared with untransduced hADSCs treated in a parallel fashion. Conclusions: These five missing TFs are known to regulate hepatocyte differentiation and some are required to establish the competence of the foregut endoderm. Presumably due to their mesenchymal lineage, hADSCs do not express these endodermal TFs and are not fully competent to respond to critical developmental signals. Supplementation of these TFs may induce competency and enhance the differentiation of hADSCs into hepatocytes. [source] Epithelial differentiation of adipose-derived stem cells for laryngeal tissue engineering,THE LARYNGOSCOPE, Issue 1 2010Jennifer L. Long MD Abstract Objectives/Hypothesis: One potential treatment option for severe vocal fold scarring is to replace the vocal fold cover layer with a tissue-engineered structure containing autologous cells. As a first step toward that goal, we sought to develop a three-dimensional cell-populated matrix resembling the vocal fold layers of lamina propria and epithelium. Study Design: Basic science investigation. Methods: Adipose-derived stem cells were cultured in fibrin hydrogels with various growth factors. At the end of the culture period, matrices were sectioned and labeled with immunomarkers to identify cell phenotype. Results: Adipose-derived stem cells survived, attached, and populated three-dimensional fibrin matrices. Under select conditions, a superficial layer of cells expressing epithelial marker proteins overlay a deeper mesenchymal cell layer. Conclusions: A three-dimensional structure of fibrin and adipose-derived stem cells was created as a prototype vocal fold replacement. Two segregated cell phenotypes occurred, producing a bilayered structure resembling epithelium over lamina propria. This preliminary work demonstrates the feasibility of tissue engineering to produce structures for vocal fold replacement. Laryngoscope, 2010 [source] Chondrogenic differentiation of adipose-derived stem cellsANZ JOURNAL OF SURGERY, Issue 11 2009Tony Goldschlager MBBS No abstract is available for this article. [source] Adipose-derived stem cell: a better stem cell than BMSCCELL BIOCHEMISTRY AND FUNCTION, Issue 6 2008Yanxia Zhu Abstract 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,×,105 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. [source] | |||||||||||||