Culturability of rat bone marrow stromal cells and evaluation for osteoblastic formation

Objectives: We investigated culturability of bone marrow stromal cells of young mature rats and evaluated cultured cells with regard to histomorphologic features and osteoblastic formation. Methods: Sixteen mature Wistar rats were sacrificed under high dose of ether anesthesia. Their femurs and tib- ias were removed, medullas and metaphyses were washed with carrier serum and the collected material was cultured in DME/F12 serum. The cells in the test medium and at the bottom of Petri dishes were studied under inverted microscope and were photographed. Then, the cells at the bottom were stained with the picro-thionin technique, examined under light microscope, and photographed. Following trypsinizing, cluster cells were dissolved and smears were prepared for histomorphologic evaluation of stromal cells. Results: Rat bone marrow cells in the culture showed a high percentage of reproducibility (93.8%; 15/16). The stromal cells in Petri dishes were of different morphology, and were interspersed with large multinucleated osteoblast-like cells following staining with the picro- thionin technique. Conclu s ion : Our findings favor the opinion that cells harvested in bone marrow cell culture are very similar to osteoblastic cells and that they may stem from osteo- progenitor cells which have multifacet differention ability.