Osmotic tolerance and membrane permeability characteristics of in-suspension and adherent osteoblasts
Liu Y., Ma XH., Liu TQ., Cui ZF.
In order to decrease the osmotic damage and chemical cytotoxicity of the cryoprotectant with high concentration, an appropriate scheme of loading and removing the cryoprotective agents is necessary during optimizing the procedure of effective cell and tissue cryopreservation. In this study, the membrane permeability of SD rat cranium parietal bone-derived osteoblasts was studied by microscopy image analysis method. It was found that the osteoblasts isosmotic cell volume V o of the osteoblast is 2585.22 μm 3 , and the osmotic behavior of the osteoblasts behaves as ideal osmometers. According to the Boyle van't Hoff plot, the osmotically inactive volume V b of the osteoblast is 0.335 V o . The found hydraulic conductivities of the osteoblast cell membrane in the presence of cryoprotective agents, dimethyl sulfoxide and 1, 2-propanediol, are 1.5×10 -13 and 5×10 -13 m 3 · N -1 · s -1 , respectively, and the permeability of the above cryoprotectants are 7.5×10 -11 and 120×10 -11 mol · N -1 · s -1 , respectively. The experimental data indicate that the anisotonic condition tolerance of the adherent osteoblasts is lower than that of the osteoblasts in suspension. The study results obtained provide initial biophysical data to characterize osteoblasts and will provide a basis for designing the optimal cryopreservation procedures for engineered bone tissue.