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Markers CD34 (marker + cd34)
Selected AbstractsAbsence of lymphatic vessels in human dental pulp: a morphological studyEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2010Renato Gerli Gerli R, Secciani I, Sozio F, Rossi A, Weber E, Lorenzini G. Absence of lymphatic vessels in human dental pulp: a morphological study. Eur J Oral Sci 2010; 118: 110,117. © 2010 The Authors. Journal compilation © 2010 Eur J Oral Sci Few and controversial data are available in the literature regarding the presence of lymphatic vessels in the human dental pulp. The present study was designed to examine morphologically the existence of a lymph drainage system in human dental pulp. Human dental pulp and skin sections were immunohistochemically stained with specific antibodies for lymphatic endothelium (D2-40, LYVE-1, VEGFR-3 [vascular endothelial growth factor receptor-3], and Prox-1), with the pan-endothelial markers CD31 and von Willebrand factor (vWF), and with the blood-specific marker CD34. Several blood vessels were identified in human pulps and skin. Lymphatic vessels were found in all human skin samples but in none of the pulps examined. Western blotting performed on human dermis and on pulps treated with collagenase (to remove odontoblasts) confirmed these results. Transmission electron microscopy indicated that vessels which, by light microscopy, appeared to be initial lymphatic vessels had no anchoring filaments or discontinuous basement membrane, both of which are typical ultrastructural characteristics of lymphatic vessels. These results suggest that under normal conditions human dental pulp does not contain true lymphatic vessels. The various theories about dental pulp interstitial fluid circulation should be revised accordingly. [source] Endomyocardial biopsy derived adherent proliferating cells,A potential cell source for cardiac tissue engineeringJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 3 2010Marion Haag Abstract Heart diseases are a leading cause of morbidity and mortality. Cardiac stem cells (CSC) are considered as candidates for cardiac-directed cell therapies. However, clinical translation is hampered since their isolation and expansion is complex. We describe a population of human cardiac derived adherent proliferating (CAP) cells that can be reliably and efficiently isolated and expanded from endomyocardial biopsies (0.1,cm3). Growth kinetics revealed a mean cell doubling time of 49.9,h and a high number of 2.54,×,107 cells in passage 3. Microarray analysis directed at investigating the gene expression profile of human CAP cells demonstrated the absence of the hematopoietic cell markers CD34 and CD45, and of CD90, which is expressed on mesenchymal stem cells (MSC) and fibroblasts. These data were confirmed by flow cytometry analysis. CAP cells could not be differentiated into adipocytes, osteoblasts, chondrocytes, or myoblasts, demonstrating the absence of multilineage potential. Moreover, despite the expression of heart muscle markers like ,-sarcomeric actin and cardiac myosin, CAP cells cannot be differentiated into cardiomyocytes. Regarding functionality, CAP cells were especially positive for many genes involved in angiogenesis like angiopoietin-1, VEGF, KDR, and neuropilins. Globally, principal component and hierarchical clustering analysis and comparison with microarray data from many undifferentiated and differentiated reference cell types, revealed a unique identity of CAP cells. In conclusion, we have identified a unique cardiac tissue derived cell type that can be isolated and expanded from endomyocardial biopsies and which presents a potential cell source for cardiac repair. Results indicate that these cells rather support angiogenesis than cardiomyocyte differentiation. J. Cell. Biochem. 109: 564,575, 2010. © 2009 Wiley-Liss, Inc. [source] Human mast cells express receptors for IL-3, IL-5 and GM-CSF; a partial map of receptors on human mast cells cultured in vitroALLERGY, Issue 10 2004C. Dahl Background:, Mast cells have long been recognized as the principal cell type that initiates the inflammatory response characteristic of acute allergic type 1 reactions. Our goal has been to further characterize maturation of progenitors to mast cells. Methods:, Mast cells were cultured from human cord blood derived CD133+ progenitors. Mast cell function was tested using histamine release. During differentiation mast cells surface marker expression was monitored by flow cytometry. Results:, CD133+ progenitors expressed the early haematopoietic and myeloid lineage markers CD34, CD117, CD13 and CD33. Mature mast cells expressed CD117, CD13 and CD33, and expression of the high affinity immunoglobulin E recpetor Fc,RI increased during culture. Cytokine receptors interleukin (IL)-5R, IL-3R, granulocyte-macrophage-colony stimulating factor (GM-CSF)R and IL-18R were expressed at high levels during maturation. Chemokine receptors CXCR4 and CXCR2 were highly expressed on both newly purified CD133+ cells and mature cells. Conclusion:, Human mast cells can be cultured from a CD34+/CD117+/CD13+/CD33+ progenitor cell population in cord blood that is tryptase and chymase negative. Developing and mature mast cells express a wide range of chemokine and cytokine receptors. We found high levels of expression of CD123, IL-5R and GM-CSF receptors, also found on eosinophils and basophils, and high levels of expression of the receptor for the inflammatory cytokine IL-18. [source] Differential distribution of haematopoietic and nonhaematopoietic progenitor cells in intralesional and extralesional keloid: do keloid scars provide a niche for nonhaematopoietic mesenchymal stem cells?BRITISH JOURNAL OF DERMATOLOGY, Issue 6 2010S.A. Iqbal Summary Background, Keloid disease is a benign, quasineoplastic disease with a high recurrence rate. Mesenchymal-like stem cells (MLSC) have previously been demonstrated in keloid scars and may be involved in keloid pathobiology. However, as these cells have only been examined by single colour fluorescence activated cell sorting (FACS) alone, they need to be more comprehensively characterized so that the key cellular contributors to keloid scars can be better understood. Objectives, To identify and characterize MLSC in intralesional and extralesional keloid, and to distinguish haematopoietic stem cells (HSC) from mesenchymal stem cells (MSC). Methods and patients, Punch biopsies from intralesional (top, middle and margin) and extralesional keloid scar sites were obtained from 17 patients with a keloid. Multicolour FACS analysis using antibodies specific for HSC markers CD34 and CD117 and MSC markers CD13, CD29, CD44 and CD90 was performed on freshly isolated keloid scar cells and on passage 0 and 1 cells. This was complemented by real-time quantitative polymerase chain reaction (PCR) and immunohistological in situ analyses. Results, Keloid scars contain distinct subpopulations of MLSCs. Cells positive for CD13, CD29, CD44 and CD90 were found to be significantly (P < 0·05) higher in the top and middle compartments of keloid scars compared with extralesional skin, where cells positive for CD34, CD90 and CD117 (representing HSCs) predominated. A unique population of CD34+ cells (cells positive for CD13, CD29, CD34, CD44 and CD90) were found in keloid scars and in extralesional skin. FACS and quantitative PCR analysis showed that many of the MSC markers were progressively downregulated and all HSC markers were lost during extended keloid fibroblast culture up to passage 1. Conclusion, We have found distinct subpopulations of haematopoietic and nonhaematopoietic MSC in keloid scars, whereby HSC accumulate extralesionally, while keloids seem to provide a niche environment for nonhaematopoietic MSC. Future therapy of keloids may have to target differentially both stem cell populations in order to deprive these tumours of their regenerative cell pools. [source] | ||||||||||