Patent ID: 7736894

Claim:
A method for producing a human skin tissue, in which a human skin tissue is constructed on a body surface of an immunodeficient non-human animal, which method comprises: (a) grafting a cell-injectable, hat-shaped chamber ( 6 ) having a dome-shaped pan ( 2 ) and a collar part ( 1 ) into the dorsal skin of said immunodeficient non-human animal, wherein the grafting step comprises: (i) cutting a circular form in the dorsal skin of said immunodeficient non-human animal; (ii) inserting said cell-injectable, hat-shaped chamber into said dorsal skin such that the dome-shaped part of said cell-injectable, hat-shaped chamber is exposed and only the collar part is covered by said dorsal skin; and (iii) securing said cell-injectable, hat-shaped chamber in said dorsal skin by an adhesive or suturing; (b) injecting a cell suspension containing human fibroblasts and human keratinocytes into said cell-injectable, hat-shaped chamber; (c) at least seven days after the grafting step, cutting the dome-shaped part of said cell-injectable, hat-shaped chamber a first time such that 60% to 80% of the cross-sectional area of the dome-shaped part is open; (d) mounting a gas-permeable member over the opening in the dome-shaped part resulting from said first cutting; (e) after seven to ten days, cutting the dome-shaped part a second time such that 100% of the cross-sectional area of the dome-shaped part is open; (f) mounting a gas-permeable member over the opening in the dome-shaped part resulting from said second cutting; and (g) removing said cell-injectable, hat-shaped chamber from said immunodeficient non-human animal; wherein the gas-permeable membrane mounted in each of steps (d) and (f) is selected from the group consisting of gauze, a nonwoven fabric, a cloth, a metal net having a pore diameter ranging from 0.1 to 0.5 mm, a resin net having a pore diameter ranging from 0.1 to 0.5 mm, and a cotton net having a pore diameter ranging from 0.1 to 0.5 mm.