Membrane

1. A membrane for supporting growth of cells, the membrane being non-biodegradable and porous, wherein pores of said membrane are between approximately 0.2 μm and 0.5 μm diameter, wherein pore density of the membrane is between 1×10 7 and 3×10 8 pores per cm 2 , said membrane comprising a layer of retinal pigment epithelial cells, or retinal pigment epithelial cell precursors, or retinal derivative cells formed from the differentiation of retinal pigment epithelial cells on the membrane.

2. A membrane according to claim 1 wherein the membrane hydraulic conductance of the membrane is more than 50×10 −10 in sec −1 Pa −1 .

3. A membrane according to claim 1 wherein the membrane is sterilised by gamma irradiation, ethylene oxide, autoclaving or UV sterilization without degrading.

4. A membrane according to claim 1 , wherein the membrane is sealed by ultrasonic sealing, radio frequency sealing or insert moulding.

5. A membrane according to claim 1 , wherein said membrane has a maximum thickness of approximately 11 μm.

6. A membrane according to claim 1 , wherein said membrane has a maximum weight of approximately 1.5 mg/cm 2 .

7. A membrane according to claim 1 , wherein the membrane is hydrophilic.

8. A membrane according to claim 1 , having a pH of 4 to 8.

9. A membrane according to claim 1 , comprising a coating on at least one side.

10. A membrane according to claim 9 , wherein the coating is laminin, matrigel, fibronectin, or PLGA.

11. A membrane according to claim 9 , comprising a pharmacological or biological agent, bound to the coating.

12. A membrane according to claim 1 , wherein the cells are human retinal pigmented epithelial cells.

13. A membrane according to claim 12 , wherein the cells are immortalised cells.

14. A membrane according to claim 1 , wherein the membrane is made from a hydrophilic polymer selected from the group consisting of: a polyester, a polyurethane, a polyurea-urethane, a polyamide, a polyether-ester, a polycarbonate, a polyacrylate, poly(tetrafluoroethene), a polysiloxane, a polyolefin, and polyoxymethylene.

15. A method comprising:

seeding one or more retinal pigment epithelial cells, or retinal pigment epithelial cell precursors, or retinal derivative cells onto a membrane, to form and support at least one colony of cells, wherein the membrane is substantially non-biodegradable and porous and has a maximum thickness of approximately 11 μm, wherein pore density of the membrane is between 1×10 7 and 3×10 8 pores per cm 2 and pores of said membrane are between approximately 0.2 μm and 0.5 μm diameter.

16. A method for using a membrane according to claim 1 , comprising:

transplanting the membrane into an eye.

17. A method according to claim 16 , wherein the cells are autologous to the eye.

18. A method according to claim 16 , wherein the eye is in a patient that has age related macular degeneration.

19. A membrane comprising a substantially non-biodegradable and porous support layer coated on at least one side with a coating comprising glycoprotein, wherein pores of said membrane are between approximately 0.2 μm and 0.5 μm diameter, wherein the pore density of the support layer is between 1×10 7 and 3×10 8 pores per cm 2 .

20. A method of seeding cells onto a membrane comprising the step of:

seeding the cells onto the membrane at a density of 200,000 cells per cm 2 or greater, wherein pores of said membrane are between approximately 0.2 μm and 0.5 μm diameter, wherein pore density of the membrane is between 1×10 7 and 3×10 8 pores per cm 2 , and wherein the cells are retinal pigment epithelial cells, or retinal pigment epithelial cell precursors, or retinal derivative cells.

21. A membrane for supporting the growth of cells, the membrane comprising a polyester and being in the form of a substantially non-biodegradable and porous support layer having a maximum thickness of approximately 11 μm and coated on at least one side with a coating comprising a glycoprotein, the pores being approximately 0.4 μm in diameter, wherein the pore density of the pores in the support layer is approximately 1×10 8 pores per cm 2 ; further comprising a layer of retinal pigment epithelial cells, or retinal pigment epithelial cell precursors, or retinal derivative cells formed from the differentiation of retinal pigment epithelial cells on the membrane.

22. A membrane according to claim 14 wherein the hydrophilic polymer is polyester.

23. A membrane according to claim 1 or 21 wherein the membrane comprises a layer of retinal pigment epithelial cell precursors.

24. A membrane according to claim 23 wherein the retinal pigment epithelial cell precursors are human embryonic stem cells.