Epidermal cultured cell sheet, multi-layered cultured skin sheet and processes for producing those sheets

Cells are cultured on a cell culture support having a substrate surface coated with a temperature-responsive polymer whose upper or lower critical solution temperature in water is 0ˆ¼80°C, optionally forming multiple cultured cell layers by a conventional technique, and subsequently: (1) the temperature of the culture solution is brought to above the upper critical solution temperature or below the lower critical solution temperature; (2) the cultured epidermal cell sheet or multi-layered skin sheet is brought into close contact with the polymer membrane; and (3) the sheet is peeled off together with the polymer membrane. The thus obtained epidermal cultured cell sheet and multi-layered cultured skin sheet do not degrade E-cadherin or laminin 5 as contrasted with Dispase treatment and they still involve very few structural defects; these sheets hence hold great promise in clinical applications such as skin grafting.