Polysaccharide sponges for cell culture and transplantation

• US 6,425,918 B1
• Filed: 11/17/1998
• Issued: 07/30/2002
• Est. Priority Date: 05/22/1996
• Status: Expired due to Term

• Current Assignee: Ben Gurion University of The Negev
• Original Assignee: Ben Gurion University of The Negev
• Inventors: Cohen, Smadar, Glicklis, Rachel, Shapiro, Lilia
• Primary Examiner(s): Isabella, David J.
• Application Number:
  US09/180,970
• Time in Patent Office: 1,351 Days
• Field of Search: 623/7, 623/15, 623/16, 623/11, 623/66, 424/423, 424/425, 424/426, 514/773, 514/774, 514/777
• US Class Current: 623/11.11
• CPC Class Codes: A61F 2/105 Skin implants, e.g. artificial skin
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2250/0067 Means for introducing or releasing pharmaceutical products into the body
• CPC Class Codes: A61K 9/0024 Solid, semi-solid or solidifying implants, which are implanted or injected in body tissue compositions for intravenous administration, normal injectable solutions or dispersions for, e.g. subcutaneous administration A61K9/0019; brain implants A61K9/0085; (coated) prostheses, catheters or stents A61L
• CPC Class Codes: A61K 9/122 Foams; Dry foams edible foams A61K9/0056
• CPC Class Codes: A61L 27/20 Polysaccharides
• CPC Class Codes: A61L 27/3804 characterised by specific cells or progenitors thereof, e.g. fibroblasts, connective tissue cells, kidney cells
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 27/60 Materials for use in artificial skin
• CPC Class Codes: C08J 2305/02 Dextran; Derivatives thereof
• CPC Class Codes: C08J 9/26 by elimination of a solid phase from a macromolecular composition or article, e.g. leaching out
• CPC Class Codes: C08L 5/02 Dextran; Derivatives thereof

Abstract

A polysaccharide sponge characterized by having: (i) an average pore size in the range between about 10 μm to about 300 μm; (ii) an average distance between the pores being the wall thickness of the pores in the range between about 5 μm to about 270 μm; and (iii) an E-modulus of elasticity being a measure of the rigidity of the sponge in the range of about 50 kPa to about 500 kPa.

Claims

1. A polysaccharide sponge characterized by having:

(i) an average pore size in the range between about 10 μ

m to about 300 μ

m;

(ii) an average distance between the pores being the wall thickness of the pores in the range between about 5 μ

m to about 270 μ

m; and

(iii) an E-modulus of elasticity being a measure of the rigidity of the sponge in the range of about 50 kPa to about 500 kPa, wherein said sponge comprises an alginate selected from the group of alginates characterised by having;

(i) a mannuronic acid (M) residue content in the range of between about 25% and about 65% of total residues;

(ii) a guluronic acid (G) residue content in the range of between about 35% and about 75% of total residues;

(iii) a M/G ratio of about ⅓ and

about 1.86/1; and

(iv) a viscosity of the final alginate solution having 1% w/v alginate, from which the sponge is obtained in the range between about 50 cP to about 800 cP.

2. A polysaccharide sponge according to claim 1 wherein said alginate is used in the form of a sodium alginate solution having a concentration of alginate between about 1% to about 3% w/v to provide an alginate concentration between about 0.1% to about 2% w/v in the final solution from which the sponge is obtained.

3. A polysaccharide sponge according to claim 1, wherein said sponge comprises an alginate derived from brown sea algae.

4. A polysaccharide sponge according to claim 1 for use as a matrix, substrate or scaffold for implantation into a patient to replace or repair tissue that has been removed or damaged, wherein said implanted sponge is a substrate, matrix or scaffold for surrounding tissue to invade it, proliferate thereon and replace the damaged or removed tissue, or wherein said implant is an initial substrate for vascularization by the surrounding host tissue and the vascularized implant then serves as a substrate to receive injected cells of choice from the host, or grown in vitro, said injected cells being capable of rapid acclimitization and proliferation on the vascularized sponge to rapidly replace the damaged or removed tissue.

5. A polysaccharide sponge according to claim 1 for use as an implanted support for therapeutic drug delivery into a desired tissue, said drug delivery being by way of the action of genetically engineered cells or natural cells carried by said sponge and expressing said therapeutic drugs, said cells expressing said drug or expressing regulatory proteins to direct the production of the drug endogenously in said tissue.

6. A polysaccharide sponge according to claim 5, wherein said therapeutic drug expressed by said cells carried in said sponge is a therapeutic protein, wherein said cells express said protein or express regulatory proteins to direct the production of said protein endogenously in the tissue into which said sponge is implanted.

7. A polysaccharide sponge according to claim 3 for use as a matrix, substrate or scaffold for in vitro culturing of plant cells and algae.

8. A polysaccharide sponge according to claim 3 for use as a matrix, substrate or scaffold for the delivery to a tissue or organ of genetically engineered viral vectors, non-viral vectors, polymeric microspheres and liposomes all encoding or containing a therapeutic agent for said tissue or organ.

9. A polysaccharide sponge according to claim 3 for use as a matrix, substrate or scaffold for in vitro fertilization of mammalian oocytes.

10. A polvsaccharide sponge according to claim 3 for use as a matrix, substrate or scaffold for storage of fertilized mammalian oocvtes or other mammalian cells cultured in vitro.

11. A polvsaccharide sponge according to claim 3 for use as a matrix, substrate or scaffold for the transplantation of cells grown on or within said sponge in vitro into a tissue of a patient in need of said cells as a result of tissue damage, removal, or dysfunction.

12. Use of a polysaccharide sponge according to claim 3 as a matrix, substrate or scaffold for the in vitro growth of mammalian cells, plant cells, algae, or for the in vitro fertilization of mammalian oocytes.

13. Use of a polysaccharide sponge according to claim 12 for the in vitro growth of fibroblast cells.

14. Use of a polysaccharide sponge according to claim 12 for the in vitro growth of hepatocytes.

15. Use of a polysaccharide sponge according to claim 3 as a matrix, substrate or scaffold for implantation into a patient to replace or repair tissue that has been removed or damaged, wherein said implanted sponge is a substrate, matrix or scaffold for surrounding tissue to invade it, proliferate thereon and replace the damaged or removed tissue, or wherein said implant is an initial substrate for vascularization by the surrounding host tissue and the vascularized implant then serves as a substrate to receive injected cells of choice from the host or grown in vitro, said injected cells being capable of rapid acclimitization and proliferation on the vascularized sponge to rapidly replace the damaged or removed tissue.

16. Use of a polysaccharide sponge according to claim 3 as a matrix, substrate or scaffold for the transplantation of cells grown on said sponge in vitro into a tissue of a patient in need of said cells as a result of tissue damage, removal, or dysfunction.

17. Artificial skin comprising a polysaccharide sponge according to claim 3 and dermal fibroblast cells grown on said sponge in vitro to the stage wherein said cells are in an active proliferating stage suitable for transplantation to a patient in need of said artificial skin.