大鼠牙囊干细胞与珊瑚羟基磷灰石陶瓷生物相容性和成骨作用研究

In vitro osteogenic differentiation of rat dental follicle stem cells in coralline hydroxyapatite bioglass ceramics

目的观察大鼠牙囊干细胞(rat dental follicle stem cells,rDFCs)在珊瑚羟基磷灰石生物玻璃陶瓷(coralline hydroxyapatite,CHA)上的附着增殖以及成骨因子表达情况,探索二者间生物相容性。方法 10只6 d龄SD大鼠,雌雄各半,处死后剥离双侧下颌骨磨牙区牙囊组织,通过组织块酶消化法获得rDFCs,rDFCs与CHA体外复合培养,扫描电镜(SEM)观察rDFCs与CHA黏附增殖情况,RTPCR法测定rDFCs、rDFCs-CHA及rDFCs成骨诱导组黏附增殖5、7、9 d成骨基因OPN、ALP、Osterix的表达。结果 SEM观察到rDFCs在CHA上能正常黏附、生长、增殖,4 d时细胞开始相互接触,成片状黏附于CHA表面,7 d时,细胞外基质已完全覆盖CHA表面。RT-PCR结果显示rDFCs与CHA共培养5、7、9 d时,CHA促进了成骨基因OPN、ALP、Osterix的表达,rDFCs-CHA组与rDFCs组相比,Osterix基因表达:7 d时前者是后者267倍;OPN基因表达:7 d时是24.7倍,ALP基因表达:5 d时rDFCs-CHA组是rDFCs组的3.1倍(P<0.01)。结论 CHA能促进rDFCs黏附、增殖、成骨分化及表达成骨因子,二者生物相容性良好。

follicle stem cells （ Objective To observe the proliferation and expression of osteogenic factors of rat dental rDFCs） on coralline hydroxyapatite （CHA） in order to assess the biocompatibility of rDFCs and CHA. Methods Ten 6-day-old SD rats of both sexes were sacrificed for the dental follicle tissues, and then the rDFCs were isolated by enzymatic digestion. The obtained ceils were cultured with CHA in vitro. Scanning electron microscopy （SEM） was used to observe the adhesion of rDFCs on/in CHA. RT-PCR was employed to detect the expression of the osteogenic genes, osteopontin （OPN）, alkaline phosphatase （ALP） and Osterix in the rDFCs-CHA on 5, 7 and 9 d after co-culture and the rDFCs in presence and absence of osteogenic differentiation for the same periods. Results SEM showed that rDFCs could adhere, grow and proliferate on CHA, and began to merge on the surface of CHA after 4 days＇ co-culture, and extracelluar martix completely covered the CHA surface on the 7th day. RT-PCR analysis indicated that CHA promoted the expression of osteogenic genes OPN, ALP and Osterix after 5, 7 and 9 days＇ co-culture of rDFCs and CHA. Compared to the rDFCs group, Osterix was expressed by 267 times higher on day 7, OPN was 24.7 times higher on day 7, and ALP genes was 3.1 times on day 5 in the rDFCs-CHA co-culture group （P 〈 0.01 ）.Conclusion CHA promotes the adhesion, proliferation and osteogenic differentiation of rDFCs. And rDFCs and CHA are of good biocompatibility.