부산대학교 도서관

The purpose of this study is to elucidate osteoblastic characteristics of two different cell populations derived from human alveolar bone. The cells from collagenase-treated bone fragments were termed E-AB, whereas the cells from untreated bone fragments were termed N-AB. Both cell populations were subcultured up to four generations, and used for this study. To determine phosphatase activity per 104 cells, enzyme assay was carried out directly using the confluent monolayer in each well of a 96-well microplate. Protein synthesis was determined by 24 hr 14C-proline labeling. After the labeling, the cultured medium, cells and matrix layer were separately collected to determine 14Cproline incorporation. The radiolabeled proteins were separated by SDS-PAGE and determined by fluorography. The characteristics of both cell populations were as follows. The E-AB showed about 7-fold higher alkaline phosphatase activity than the N-AB's. On the other hand, no differences were observed in total acid phosphatase and tartrate -resistant acid phosphatase activities, which were less than 50% of the N-AB's alkaline phosphatase activity and about 25% of the total acid phosphatase activity, respectively. According to the results of 14C-proline labeling, both cell populations produced and secreted large quantities of Mrs of over 200 kDa proteins, procollagens and collagens into the culture media. However, the 28 K and 34 K proteins were much more evident in the E-AB's cultured medium. In both matrix layers, Mrs of 40-50 K proteins were incorporated, in addition of the large amounts of protein in the culture medium.