Peptide scaffold encapsulation of tissue cells and uses thereof

• US 20020160471A1
• Filed: 02/06/2001
• Published: 10/31/2002
• Est. Priority Date: 02/06/2001
• Status: Active Grant

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Zhang, Shuguang, Grodzinsky, Alan, Kisiday, John
• Granted Patent: US 7,449,180 B2
• Time in Patent Office: Days
• US Class Current: 435/177
• CPC Class Codes: A61K 35/12 Materials from mammals; Compositions comprising non-specified tissues or cells; Compositions comprising non-embryonic stem cells; Genetically modified cells vaccines or medicinal preparations containing antigens or antibodies A61K39/00
• CPC Class Codes: C12N 2500/25 Insulin-transferrin; Insulin-transferrin-selenium
• CPC Class Codes: C12N 2501/11 Epidermal growth factor [EGF]
• CPC Class Codes: C12N 2501/13 Nerve growth factor [NGF]; Brain-derived neurotrophic factor [BDNF]; Cilliary neurotrophic factor [CNTF]; Glial-derived neurotrophic factor [GDNF]; Neurotrophins [NT]; Neuregulins
• CPC Class Codes: C12N 2502/1317 Chondrocytes
• CPC Class Codes: C12N 2533/30 Synthetic polymers
• CPC Class Codes: C12N 2533/50 Proteins
• CPC Class Codes: C12N 5/0012 Cell encapsulation
• CPC Class Codes: C12N 5/0618 Cells of the nervous system
• CPC Class Codes: C12N 5/0655 Chondrocytes; Cartilage
• CPC Class Codes: C12N 5/0672 Stem cells; Progenitor cells; Precursor cells; Oval cells

Abstract

The invention features peptide scaffolds that are useful in the repair and replacement of various tissues. The invention also provides methods for making these scaffolds and methods for using them.

Claims

1. A macroscopic scaffold comprising amphiphilic peptides, wherein said peptides have alternating hydrophobic and hydrophilic amino acids, are complementary and structurally compatible, and self-assemble into a beta-sheet macroscopic scaffold;

and wherein said macroscopic scaffold encapsulates living cells, said cells being present in said macroscopic scaffold in a three-dimensional arrangement.

2. The macroscopic scaffold of claim 1, further encapsulating a therapeutically active compound or chemoattractant.

3. The macroscopic scaffold of claim 1, wherein said peptides comprise an adhesion site, growth factor binding site, growth factor, or sequence that provides targeting to a cell, tissue, organ, organ system, or site within an mammal.

4. The macroscopic scaffold of claim 1, wherein said living cells are neurons and said macroscopic scaffold allows axonal outgrowth by said neurons.

5. The macroscopic scaffold of claim 1, wherein said cells are chondrocytes, bone marrow cells, peristeal cells, perichondrial cells, fibroblasts, neuronal cells, hippocampal cells, epidermal cells, endothelial cells, keratinocytes, basal cells, spinous cells, granular cells, embryonic stem cells, ovarian cells, pancreatic cells, cervical cells, liver cells, or foreskin cells.

6. The macroscopic scaffold of claim 1, wherein said cells secrete extracellular matrix components.

7. The macroscopic scaffold of claim 6, wherein said secretion of extracellular matrix components increases the equilibrium compression modulus of said macroscopic scaffold by at least 50 fold.

8. The macroscopic scaffold of claim 1, wherein at least 60% of the encapsulated cells are in cell-cell contact with another encapsulated cell or with a cell outside of the scaffold.

9. A method of forming a macroscopic scaffold, said method comprising the steps of:

(a) incubating peptides and living cells in an aqueous solution comprising an iso-osmotic solute, wherein said peptides have alternating hydrophobic and hydrophilic amino acids and are complementary and structurally compatible; and

(b) adding an electrolyte to said solution sufficient to initiate self-assembly of said peptides into a beta-sheet macroscopic scaffold, whereby said cells are encapsulated by the formation of said macroscopic scaffold and are present in said macroscopic scaffold in a three-dimensional arrangement.

10. A method of forming a macroscopic scaffold of predetermined shape or volume, said method comprising the steps of:

(a) incubating peptides and living cells in an aqueous solution comprising an iso-osmotic solute, wherein said peptides have alternating hydrophobic and hydrophilic amino acids and are complementary and structurally compatible, wherein said solution is contained in a pre-shaped mold dimensioned to determine the volume or shape of said macroscopic scaffold; and

(b) adding an electrolyte to said solution sufficient to initiate self-assembly of said peptides into a beta-sheet macroscopic scaffold, whereby said cells are encapsulated by the formation of said macroscopic scaffold and are present in said macroscopic scaffold in a three-dimensional arrangement.

14. The method of claim 9, 10, or 11, further comprising subjecting said macroscopic scaffold to a predetermined compression scheme.

17. The method of claim 9, 10, or 11, wherein at least 60% of the encapsulated cells are in cell-cell contact with another encapsulated cell.

18. The method of claim 9 or 10, wherein said solution in step (a) contains less than 10 mM electrolyte, and wherein said peptides do not substantially self-assemble prior to step (b).

11. A method of regenerating a tissue, said method comprising administering to a mammal a macroscopic scaffold comprising amphiphilic peptides, wherein said peptides have alternating hydrophobic and hydrophilic amino acids, are complementary and structurally compatible, and self-assemble into a beta-sheet macroscopic scaffold;

and wherein said macroscopic scaffold encapsulates living cells, said cells being present in said macroscopic scaffold in a three-dimensional arrangement.

13. The method of claim 11 or 12, wherein said method is used to treat or prevent a cartilage defect, connective tissue defect, nervous tissue defect, epidermal lining defect, endothelial lining defect, or arthritis.

15. The method of claim 14, wherein said compression scheme induces the secretion of extracellular matrix components by said cells.

16. The method of claim 15, wherein said secretion of extracellular matrix components increases the equilibrium compression modulus of said macroscopic scaffold by at least 50-fold.

12. A method of regenerating a tissue, said method comprising administering to a mammal a solution comprising amphiphilic peptides, living cells, and an iso-osmotic solute;

wherein said peptides have alternating hydrophobic and hydrophilic amino acids and are complementary and structurally compatible, wherein said peptides do not substantially self-assemble prior to said administration, and wherein said peptides self-assemble into a beta-sheet macroscopic scaffold after said administration, thereby encapsulating said cells in vivo, said cells being present in said macroscopic scaffold in a three-dimensional arrangement.