Water Transport during Freezing of Human Dermal Fibroblast as Affected by Various Freezing Rates

In order to predict optimal freezing processes for the cryopreservation of human dermal fibroblasts, knowledge of fundamental cryobiological characteristics including cell osmotic characteristics is required. In this study, the osmotic characteristics of human dermal fibroblasts were experimentally measured. The cell volume was 5100 μm3, and the relative diameter was 21 μm, at isotonic osmolality. The cell volume change was also measured after the cells were exposed and equilibrated to different anisosmotic conditions. It was found that the cell volume was a linear function of the reciprocal of the extracellular osmolality (Boyle–van't Hoff plot). The nonosmotic volume of the cell was 36% of the isotonic volume of the cells. Then these parameters including the nonosmotic volume of the cell were used in the water transport model to simulate water transport of fibroblasts at various freezing rates between 0.01–50°C/min.