Objective      To observe the proliferation and expression of osteogenic factors of rat dental follicle stem cells (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 cells 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 (P0.01).       Conclusion      CHA promotes the adhesion

proliferation and osteogenic differentiation of rDFCs. And rDFCs and CHA are of good biocompatibility.