OBJECTIVETo study the effects of various methods of cryopreservation on the bioactivity of tissue engineered bone.

METHODSMSCs were cocultured with partialy deproteinised bone to produce tissue engineered bone. The experiment was divided into A, B, C and D group. Group A: Tissue engineered bone was stored in preservation solution with cryopreservation medium. Group B: Tissue engineered bone was stored in preservation solution without cryopreservation medium. Group C: Tissue engineered bone was stored without cryopreservation. Group D: MSCs were cultured without cryopreservation. The tissue engineered bone of group A and B had been cryopreserved at -80 degrees C for three months and thawed three months later. The electronic scanning microscope was used to evaluate the adhesion and distribution of MSCs, cell viability was measured by MTT, ALP activity was detected by p-nitrophosphate, cell cycle was analysed by flow cytometry.

RESULTSMSCs could adhere to the surface of the material and distribute in the hole of material. The cell viability of MSCs adhered to the material was C > A > B group (P < 0.01, P < 0.05). The ALP activity of MSCs adhered to material was C > A > B group (P < 0.01). The cell cycles of different groups did not change significantly; the abnormal cells were not observed.

CONCLUSIONThe choice of proper cryopreservative solution could optimize the bioactivity of tissue engineered bone.