Corneal Epithelial Sheet and Process for Producing the Same
A corneal epithelial sheet having a cell layer similar to the anterior epithelium of cornea. A corneal epithelial sheet is obtained through the step (a) of separately preparing a first cell being a self cell and a second cell whose origin is different from that of the first cell, the step (b) of planting the first cell and the second cell on a collagen layer and culturing them, and the step (c) of after proliferation of the cell and second cell resulting in formation of a cell layer, bringing the outermost stratum of the cell layer into contact with the air.
1 . A corneal epithelial sheet comprising:
a cell layer including a first cell that is an autologous cell and a second cell whose origin is different from the first cell, the first cell and the second cell being layered.
2 . The corneal epithelial sheet according to claim 1 , wherein
the first cell is at least one autologous cell selected from the group consisting of a cell derived from oral mucosal epithelium, a cell derived from conjunctival epithelium, a cell derived from nasal mucosal epithelium, and a cell derived from other mucosal epithelium, as well as a cell derived from an undifferentiated cell capable of constructing any of the mucosal epitheliums; and
the second cell is at least one cell selected from the group consisting of a cell derived from corneal epithelium, a cell derived from conjunctival epithelium, and a cell derived from amniotic membrane epithelium.
3 . The corneal epithelial sheet according to claim 2 , wherein the first cell is a cell derived from oral mucosal epithelium.
4 . The corneal epithelial sheet according to claim 2 , wherein the second cell is a cell of another individual.
5 . The corneal epithelial sheet according to claim 2 , wherein the second cell is a cell derived from corneal epithelium or a cell derived from amniotic membrane epithelium.
6 . The corneal epithelial sheet according to claim 1 , further comprising a collagen layer, wherein the cell layer is formed on the collagen layer.
7 . The corneal epithelial sheet according to claim 6 , wherein the collagen layer is derived from amniotic membrane or amniotic membrane from which the epithelium has been removed.
8 . The corneal epithelial sheet according to claim 1 , wherein the cell layer comprises at least one of the following properties or characteristics;
cells of the outermost layer are not cornified;
cells of the outermost layer are flat-shaped; and
a barrier function is provided.
9 . A process for producing a corneal epithelial sheet, comprising the following steps of:
a) separately preparing a first cell being an autologous cell and a second cell whose origin is different from that of the first cell;
b) seeding the first cell and the second cell on a collagen layer and culturing them; and
c) after proliferation of the first cell and second cell resulting in formation of a cell layer, bringing the surface of the cell layer into contact with the air.
10 . The process according to claim 9 , wherein
the first cell is at least one autologous cell selected from the group consisting of an oral mucosal epithelial cell, a conjunctival epithelial cell, a nasal mucosal epithelial cell, and other mucosal epithelial cell, as well as an undifferentiated cell capable of constructing any of the mucosal epitheliums; and
the second cell is at least one cell selected from the group consisting of a corneal epithelial cell, a conjunctival epithelial cell, and an amniotic membrane epithelial cell.
11 . The process according to claim 10 , wherein the first cell is an oral mucosal epithelial cell.
12 . The process according to claim 10 , wherein the second cell is a cell of another individual.
13 . The process according to claim 10 , wherein the second cell is a corneal epithelial cell or an amniotic membrane epithelial cell.
14 . The process according to claim 9 , wherein the step b is carried out under any of conditions,
1) in coexistence of supporting cells; and
2) in coexistence of supporting cells and in a state in which an isolation membrane with a pore size through which the supporting cell cannot pass exists between the supporting cells and the collagen layer.
15 . The process according to claim 9 , wherein the collagen layer is derived from amniotic membrane or amniotic membrane from which the epithelium has been removed.