In Vitro Investigation of Cell Compatibility of Pure -TCP Granules † Ö. AYLIN GÜRPINAR* AND M. ALI ONUR* Hacettepe University, Faculty of Science, Department of Biology, Beytepe, 06532, Ankara, Turkey ABSTRACT: In this study, osteoblastic cells were isolated from rat bone marrow and characterized. The cells were cultured on -TCP granules and the osteoblast/-TCP constructs. For this purpose, bone marrow was harvested under sterile conditions. Cell aggregates were broken up by pipetting and a cell suspension was cultured in DMEM/F12. After three days, the cells that adhered to the surface of the flask were cultured in osteoblast medium. When the cells became confluent, they were passaged and cultured in 24-well poly- styrene cell culture dishes. Characterization of the osteoblasts, cell prolifera- tion and alkaline phosphatase activity were measured on days 1, 7, 14, 21 and 30. To investigate the cell compatibility of the -TCP granules, osteoblastic cells were cultured on -TCP granules and a polystyrene cell culture dish (control group). Cell proliferation and alkaline phosphatase (ALP) activity were measured on days 1, 7, 14, 21 and 30 in both groups. Cell growth signifi- cantly increased at each time point, but on day 30 a decrease was observed. The ALP activity also increased at each time point and also decreased on day 30. This study may be regarded as the first step leading to a therapy for various bone defects. KEY WORDS: bone marrow, osteoblast, cell proliferation, ALP, osteocalcin, bone defects, tissue engineering †This study was a PhD thesis. *Author to whom correspondence should be addressed. E-Mail: gurpinar@hacettepe.edu.tr Journal of BIOACTIVE AND COMPATIBLE POLYMERS, Vol. 20 — March 2005 183 0883-9115/05/02 183–14 $10.00/0 DOI: 10.1177/0883911505051660 © 2005 SAGE Publications