Exosomes derived from human umbilical cord blood mesenchymal stem cells:isolation, identification and biological characteristics / 中国组织工程研究

ABSTRACT

BACKGROUND:Exosomes are membrane vesicles secreted by mesenchymal stem cells. Increasing studies have shown that mesenchymal stem cells can secrete exosomes via paracrine function to play a role in tissue injury. However, reports on how to isolate and identify exosomes derived from human umbilical cord blood mesenchymal stem cells are few. OBJECTIVE:To extract, purify and identify exosomes derived from human umbilical cord blood mesenchymal stem cells. METHODS:The cellculture supernatant of human umbilical cord blood mesenchymal stem cells was col ected. Exosome was extracted and purified with ultrafiltration and gradient centrifugation methods. The morphology of exosome was observed by transmission electronic microscope, and the expressions of CD63, CD81, CD90, CD73, CD105, CD29, and CD166 in exosome of mesenchymal stem cells were analyzed by fluorescent activated cellsorting. RESULTS AND CONCLUSION:Mesenchymal stem cells from human umbilical cord blood secreted exosome which exhibited el iptic or saucer-like shape and its diameter ranged from 40 to 100 nm with membrane structure. Exosome could express the common surface adhesion molecules CD63, CD81 and the surface adhesion molecules CD90, CD73, CD105, CD29, CD166 of mesenchymal stem cells. These findings indicate that exosome may be secreted by mesenchymal stem cells of human umbilical cord blood, which contains plasma membrane proteins of umbilical cord blood mesenchymal stem cells.