Human bone mesenchymal stem cells have become more important in tissue engineering

cells transplanting

and gene therapy. At present

they could be preserved at ultra-low temperatures. But freeze-drying of human bone mesenchymal stem cells is still an unsolved problem. In our research on freeze-drying of human bone mesenchymal stem cells

some lyoprotective solutions including PVP

HES

and trehalose were chosen and mixed. Then heterogeneous nucleation temperatures and the glass transition temperatures of concentrated solution of these solutions were measured by differential scanning calorimetry. In addition

the cells livability of the rehydrated samples after freeze-dried was measured by flow cytometer.It is found that the protocol of 30%PVP+20% trehalose has the higher livability with16.40%.