北京大学学报（医学版）2017，Vol.49Issue(1)：6-15,10.DOI:10.3969/j.issn.1671-167X.2017.01.002
骨形态发生蛋白-2-磷酸钙共沉淀支架与人脂肪间充质干细胞构建新型组织工程化骨
A novel tissue-engineered bone constructed by using human adipose-derived stem cells and biomimetic calcium phosphate scaffold coprecipitated with bone morphogenetic protein-2
摘要
Abstract
Objective:To construct a novel biomimetic calcium phosphate (BioCaP) scaffold loaded with bone morphogenetic protein-2 (BMP-2),and to investigate its role in the osteogenesis of human adipose-derived stem cells (hASCs) in vitro and in vivo.Methods:The BioCaP scaffold coprecipitated with BMP-2 (BMP-2-BioCaP) was constructed in this study.Field emission scanning electron microscopy (SEM) was used to analyze the morphology of the surfaces.The release kinetics was measured to evaluate the slow-release characteristics in vitro.BMP-2-BioCaP was immersed in proliferation medium (PM) or osteogenic medium (OM),respectively.The supernatants were collected and used to culture hASCs in vitro.Cell numbers were determined using the cell-counting kit-8 (CCK-8) to assess the cell proliferation.After 7 and 14 days,alkaline phosphatase (ALP) staining and quantification were performed to test the activity of ALP.After 14 and 21 days,the calcification deposition was determined by alizarin red S (ARS) staining and quantification.The expressions of the osteoblast-related genes were tested on day 4 and day 14.In the in vivo study,6 nude mice were used and implanted subcutaneously into the back of the nude mice for 4 groups:(1) BioCaP scaffold only,(2) BioCaP scaffold + hASCs,(3) BMP-2-BioCaP scaffold,(4) BMP-2-BioCaP scaffold + hASCs (test group).After 4 weeks of implantation,hematoxylin-eosin (HE) staining was performed to evaluate the in vivo osteogenesis of hASCs.Results:SEM observations showed that BioCaP and BMP-2-BioCaP scaffold were entirely composed of straight,plate-like and sharp-edged crystal units,and the length of the crystal units varied between 5 and 10 μm.Release kinetics analysis demonstrated that BMP-2 incorporated with BioCaP could be released at certain concentration and last for more than 21 days,and the accumulative protein release could reach 20％.CCK-8 assays showed that cell proliferation was not significantly affected by BMP-2BioCaP.ALP activity was higher by the induction of OM + BMP-2-BioCaP than of the other groups (P ＜0.01).More mineralization deposition and more expressions of osteoblast-related genes such as Runt-related transcription factor 2 (RUNX2),ALP,osteopontin (OPN) and osteocalcin (OC) were determined in the OM + BMP-2-BioCaP group at different time points (P ＜0.01).HE staining showed that,in the test group and BMP-2-BioCaP scaffold group,the extracellular matrix (ECM) with eosinophilic staining were observed around hASCs,and newly-formed bone-like tissues could be found in ECM around the scaffold materials.Moreover,compared with the BMP-2-BioCaP scaffold group,more bone-like tissues could be observed in ECM with typical structure of bone tissue in the test groups.No obvious positive results were found in the other groups.Conclusion:BMP-2-BioCaP scaffold could achieve slow-release of BMP-2 and promote the osteogenic differentiation of hASCs in vitro and in vivo.The novel tissue-engineered bone composed of hASCs and BMP-2-BioCaPis promising for the repair of bone defect.关键词
骨形态发生蛋白质类/磷酸钙类/沉淀/人脂肪间充质干细胞/组织工程Key words
Bone morphogenetic proteins/Calcium phosphates/Precipitation/Human adipose-derived stem cells/Tissue engineering分类
医药卫生引用本文复制引用
姜蔚然,张晓,刘云松,吴刚,葛严军,周永胜..骨形态发生蛋白-2-磷酸钙共沉淀支架与人脂肪间充质干细胞构建新型组织工程化骨[J].北京大学学报（医学版）,2017,49(1):6-15,10.基金项目
国家自然科学基金(81400484)和北京大学口腔医院青年科研基金项目(YS020213)资助 Supported by the National Natural Science Foundation of China (81400484) and Youth Foundation of Peking University School and Hospital of Stomatology (YS020213) （81400484）
