Cryopreservation Effect on Proliferation and Differentiation Potential of Cultured Chorion Cells

BACKGROUND: Fetoplacental tissues including the early chorion contain stem cells with various morphological and functional characteristics .Cultured chorionic cells may be used in perspective therapies of different pathologies. OBJECTIVE: To investigate the effect of cryopreservation on proliferation and differentiation potential of chorion cell culture (ChCC). MATERIALS AND METHODS: Five freezing programs for ChCC were compared: Program 1, cooling from 25°C down to -30°C at 0.5°C/min; Program 2, cooling from 25°C down to -30°C at 1°C/min; Program 3, cooling from 25°C down to -10°C at 1°C/min with further cooling down to - 80°C at 10°C/min; Program 4, cooling from 25°C down to -5°C at 1°C/min with further cooling down to -80°C at 10°C/min; Program 5, cooling from 25°C down to -6°C at 1°C/min with further crystal seeding by adding the surplus nitrogen into the chamber, and cooling down to -80°C at 10°C/min. Viability, adhesion, proliferation and directed differentiation were examined. RESULTS: Freezing program 5 achieved the best result, with the highest viability, adhesion, proliferation and directed differentiation. CONCLUSION: The data may help establishing better cryopreservation protocols for perspective chorionic cell lines and their further application in biotechnology.