title: Human CD34/CD90 ASCs are capable of growing as sphere clusters, producing high levels of VEGF and forming capillaries.
abstract: BACKGROUND
  Human adult adipose tissue is an abundant source of mesenchymal stem cells (MSCs). Moreover, it is an easily accessible site producing a considerable amount of stem cells.
  
  
  RESULTS
  In this study, we have selected and characterized stem cells within the stromal vascular fraction (SVF) of human adult adipose tissue with the aim of understanding their differentiation capabilities and performance. We have found, within the SVF, different cell populations expressing MSC markers--including CD34, CD90, CD29, CD44, CD105, and CD117--and endothelial-progenitor-cell markers--including CD34, CD90, CD44, and CD54. Interestingly, CD34(+)/CD90(+) cells formed sphere clusters, when placed in non-adherent growth conditions. Moreover, they showed a high proliferative capability, a telomerase activity that was significantly higher than that found in differentiated cells, and contained a fraction of cells displaying the phenotype of a side population. When cultured in adipogenic medium, CD34(+)/CD90(+) quickly differentiated into adipocytes. In addition, they differentiated into endothelial cells (CD31(+)/VEGF(+)/Flk-1(+)) and, when placed in methylcellulose, were capable of forming capillary-like structures producing a high level of VEGF, as substantiated with ELISA tests.
  
  
  CONCLUSIONS
  Our results demonstrate, for the first time, that CD34(+)/CD90(+) cells of human adipose tissue are capable of forming sphere clusters, when grown in free-floating conditions, and differentiate in endothelial cells that form capillary-like structures in methylcellulose. These cells might be suitable for tissue reconstruction in regenerative medicine, especially when patients need treatments for vascular disease.
authors: Dipartimento di Medicina Sperimentale, Sezione di Istologia ed Embriologia, Tissue Engineering and Regenerative Medicine Laboratory, Seconda Università di Napoli, Napoli, Italy.
authors: Francesco
authors: F
authors: De Francesco
authors: Virginia
authors: V
authors: Tirino
authors: Vincenzo
authors: V
authors: Desiderio
authors: Giuseppe
authors: G
authors: Ferraro
authors: Francesco
authors: F
authors: D'Andrea
authors: Mariateresa
authors: M
authors: Giuliano
authors: Guido
authors: G
authors: Libondi
authors: Giuseppe
authors: G
authors: Pirozzi
authors: Alfredo
authors: A
authors: De Rosa
authors: Gianpaolo
authors: G
authors: Papaccio
mesh_terms: D000273:Adipose Tissue / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D018952:Antigens, CD34 / Q000276:immunology*; D002196:Capillaries / Q000254:growth & development*; D002454:Cell Differentiation; D002455:Cell Division; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006801:Humans; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013234:Stem Cells / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D018800:Thy-1 Antigens / Q000276:immunology*; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis*
chemical_list: D018952:Antigens, CD34; D018800:Thy-1 Antigens; D042461:Vascular Endothelial Growth Factor A