Ki67 Protein: Important Proliferative Marker for Cultured Mesenchymal Stem Cells Evaluation

Bone marrow-derived mesenchymal stem cells (BM-MSCs) have attracted increasing attention in recent years as a possible reserve of stem cells that may be useful for clinical application in regenerative medicine, gene therapy, and tissue engineering. BM-MSCs have some characteristics, including easily accessible, high proliferation capacity, multi-potential plastic, and adherent ability. The self-renewal of MSCs could be measured by endogenous the city of Kiel-67 (Ki-67) and exogenous Bromodeoxyuridine (BrdU) markers. Since BrdU has a side effect on cell self-renewal followed by nucleus incorporation, Ki-67 protein as a supplementary marker could be applied to examine the proliferation potential of the cells. This study was designed to evaluate and compare the BM-MSCs proliferation rate by BrdU and Ki-67 markers. First, BM-MSCs characterized for cell morphology, CD71 and CD90 markers expression, and osteocyte and adipocyte differentiation properties. Then this research study showed that BrdU and Ki-67 exhibited different patterns of proliferation at 24–96 h after culture. Also, the Ki-67 marker had no interposition on self-renewal, unlike BrdU. It seems that in vitro identifying of proliferation rate with Ki-67 is more effective than BrdU.