Metabolic activity of cultured skin grafts cryopreserved in different forms

Cultured epidermal cells in the form of coherent sheets have been used for the treatment of skin defects. Metabolic activity of fresh and in liquid nitrogen cryopreserved keratinocyte suspensions and three forms of coherent cultured skin sheets were compared with the aim to find the most appropriate form of skin cultures for cryopreservation. Keratinocytes cultured from cryopreserved suspensions formed a confluent layer in 8-10 days after thawing, showing 95% activity of the fresh confluent cultures. Cryopreserved cultured epidermal sheets attached to the bottom of the dish as well as recombined human/pig skin (RHPS) reached more than 70% of the metabolic activity of fresh grafts following 24 h regeneration in the incubator after thawing. Cultured epidermal sheets detached from the dish and mounted on tulle grass reached only 28% of the fresh graft metabolic activity under the same conditions.