Transferrin promotes calcified nodule formation in rat bone marrow cell culture with dexamethasone

Some chemicals can promote the differentiation of stem cells and the formation of hard tissues. In this study, the effects of transferrin on calcified nodule formation were evaluated using bone marrow cells obtained from the femora of Fischer 344 rats. Transferrin was added to the culture medium to promote the proliferation and differentiation of stem cells among the bone marrow cells into osteoblasts or chondroblasts. Calcified nodule formation was confirmed macroscopically in the culture medium and evaluated quantitatively by measuring Ca2+ in the solution after demineralization using formic acid. The cells were cultured in 2 ml of minimum essential medium with 20 μl of solution containing 100, 200 or 400 ng of transferrin. Dexamethasone was also added to the medium at 10 nmol. Subculturing was performed for 2 weeks. The concentration of Ca2+ after decalcification of the calcified nodule formed in the bone marrow cell culture with dexamethasone was approximately 10 mg/ml. The addition of 100~200 ng of transferrin to the bone marrow cell culture resulted in the maximum concentration of Ca2+ and size of the formed calcified nodule in the medium. For calcified nodule formation by bone marrow cells, the optimal concentration of transferrin in the culture medium was suggested to be 200 ng in 2 ml. This study suggested that transferrin is beneficial together with dexamethasone. It may play an important role in bone formation in vivo.