Nucleotides metabolizing ectoenzymes as possible markers of mesenchymal stem cell osteogenic differentiation.

Growing murine mesenchymal stem cells (mMSCs) from mouse bone marrow decreased their rate of proliferation in the presence of benzoylbenzoyl-ATP persistently, but the inhibitory effect of ATP was strong only in a concentration of 50 μmol·L(-1) and lasted for 48 h in culture. These results hinted at ATP hydrolysis by the cell surface enzymes at the lower concentrations and thus it may be not able to inhibit MSCs. By using ATP, ADP, or AMP as substrates, we tested the ectonucleotidase activity on the surface of undifferentiated MSCs and MSC-derived osteoblasts.