Composite scaffolds and methods using same for generating complex tissue grafts

• US 20090035349A1
• Filed: 09/29/2008
• Published: 02/05/2009
• Est. Priority Date: 04/30/2001
• Status: Active Grant

• Current Assignee: Yissum Research Development Company of the Hebrew University of Jerusalem Ltd. (Hebrew University of Jerusalem)
• Original Assignee: Yissum Research Development Company of the Hebrew University of Jerusalem Ltd. (Hebrew University of Jerusalem)
• Inventors: Pelled, Gadi, Domb, Abraham, Azzam, Tony, Gazit, Dan, Turgeman, Gadi
• Granted Patent: US 8,197,553 B2
• Time in Patent Office: Days
• US Class Current: 424/423
• CPC Class Codes: A61L 2300/414 Growth factors
• CPC Class Codes: A61L 2300/426 Immunomodulating agents, i.e. cytokines, interleukins, interferons
• CPC Class Codes: A61L 2300/604 Biodegradation
• CPC Class Codes: A61L 2430/36 for embolization or occlusion, e.g. vaso-occlusive compositions or devices artificial blood vessels A61L27/507
• CPC Class Codes: A61L 27/18 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/20 Polysaccharides
• CPC Class Codes: A61L 27/22 Polypeptides or derivatives thereof , e.g. degradation products
• CPC Class Codes: A61L 27/3604 characterised by the human or animal origin of the biological material, e.g. hair, fascia, fish scales, silk, shellac, pericardium, pleura, renal tissue, amniotic membrane, parenchymal tissue, fetal tissue, muscle tissue, fat tissue, enamel
• CPC Class Codes: A61L 27/3625 Vascular tissue, e.g. heart valves
• CPC Class Codes: A61L 27/38 containing added animal cells organs or tissue containing native cells A61L27/36
• CPC Class Codes: A61L 27/3839 characterised by the site of application in the body materials for artificial blood vessels A61L27/507; materials for use in artificial skin A61L27/60
• CPC Class Codes: A61L 27/3886 comprising two or more cell types
• CPC Class Codes: A61L 27/3891 as distinct cell layers
• CPC Class Codes: A61L 27/3895 using specific culture conditions, e.g. stimulating differentiation of stem cells, pulsatile flow conditions
• CPC Class Codes: A61L 27/40 Composite materials, i.e. containing one material dispersed in a matrix of the same or different material
• CPC Class Codes: A61L 27/48 with macromolecular fillers
• CPC Class Codes: A61L 27/507 for artificial blood vessels apparatus for applying cells on a blood vessel prosthesis A61F2/062
• CPC Class Codes: A61L 27/54 Biologically active materials, e.g. therapeutic substances A61L27/227 takes precedence
• CPC Class Codes: A61L 27/58 Materials at least partially resorbable by the body
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence
• CPC Class Codes: C08L 71/02 : Polyalkylene oxides
• CPC Class Codes: C12M 25/14 : Scaffolds; Matrices in general C12N5/0068
• CPC Class Codes: C12N 2501/155 : Bone morphogenic proteins [BMP]; Osteogenins; Osteogenic factor; Bone inducing factor
• CPC Class Codes: C12N 2502/28 : Vascular endothelial cells
• CPC Class Codes: C12N 2510/00 : Genetically modified cells
• CPC Class Codes: C12N 2533/40 : Polyhydroxyacids, e.g. polymers of glycolic or lactic acid (PGA, PLA, PLGA); Bioresorbable polymers
• CPC Class Codes: C12N 2533/54 : Collagen; Gelatin
• CPC Class Codes: C12N 2533/70 : Polysaccharides
• CPC Class Codes: C12N 2533/72 : Chitin, chitosan
• CPC Class Codes: C12N 5/0068 : General culture methods using substrates for specific animal cell type C12N5/06
• CPC Class Codes: C12N 5/0662 : Stem cells

Abstract

A composite scaffold for engineering a heterogeneous tissue is provided. The composite scaffold includes: (a) a first scaffold being capable of supporting formation of a first tissue type thereupon; and (b) a second scaffold being capable of supporting formation of a second tissue type thereupon; wherein the first scaffold and the second scaffold are arranged with respect to each other such that when the first scaffold supports the first tissue type and the second scaffold supports the second tissue type, a distance between any cell of the second tissue type and the first tissue type does not exceed 200 μm.

Claims

1-64. -64. (canceled)

65. A method of inducing the formation of a heterogeneous tissue, the method comprising:

(a) providing a first scaffold being capable of supporting formation of a first tissue type thereupon;

(b) providing a second scaffold being capable of supporting formation of a second tissue type thereupon;

(c) embedding said first scaffold in said second scaffold thereby forming a composite scaffold, wherein said first scaffold and said second scaffold are arranged with respect to each other such that when said first scaffold supports said first tissue type and said second scaffold supports said second tissue type, a distance between any cell of said second tissue type and said first tissue type does not exceed 200 μ

m; and

(d) contacting said composite scaffold with cells of said first tissue type and cells of said second tissue type.

66. The method of claim 65, wherein said contacting is effected by ex-vivo seeding said cells on said composite scaffold.

67. The method of claim 65, wherein said contacting is effected by implanting said composite scaffold in a subject.

68. The method of claim 65, wherein said step of embedding is effected such that when said first scaffold supports said first tissue type and said second scaffold supports said second tissue type, a distance between any cell of said second tissue type and said first tissue type does not exceed 200 μ

m.

69. The method of claim 65, wherein said first scaffold is a filamentous scaffold having a diameter not exceeding 0.5 mm.

70. The method of claim 65, wherein said second scaffold is a porous continuous scaffold.

71. The method of claim 69, wherein said filamentous scaffold is a selected so as to enable said first tissue type to form substantially tubular structures thereupon.

72. The method of claim 65, wherein said composite scaffold comprises a plurality of molecules of a polymeric backbone cross-linked therebetween via L and D stereoisomers of a linker molecule

73. The method of claim 65, wherein said first tissue type is vascular tissue.

74. The method of claim 65, wherein said second tissue type is structural tissue selected from the group consisting of bone tissue, cartilage tissue, adipose tissue, connective tissue and muscle tissue.

75. The method of claim 65, wherein said first scaffold and/or said second scaffold further include a bioactive agent associated therewith.

76. The method of claim 65, wherein said bioactive agent is selected from the group consisting of a cell proliferation factor, a cell differentiation factor, a cell attracting factor and a pharmacologically active factor.

77. The method of claim 65, further comprising the step of growing said first tissue type on said first scaffold and/or growing said second tissue type on said second scaffold prior to step (c).

78. The method of claim 65, further comprising growing said second tissue type on said second scaffold prior to step (c) or step (d).

79. The method of claim 65, wherein said first scaffold is selected so as to enable colonization and/or proliferation of at least one cell type composing said first tissue type.

80. The method of claim 65, wherein said second scaffold is selected so as to enable colonization and/or proliferation of at least one cell type composing said second tissue type.

81. The method of claim 65, wherein said first scaffold and/or second scaffold are degradable upon exposure to predetermined environmental conditions.

82. The method of claim 65, wherein said predetermined environmental conditions are selected from the group consisting of presence of hydrolytic enzymes, presence of proteasomal enzymes, pH lower than 5 and reducing conditions.

83. An engineered tissue graft generated using the method of claim 66.

84. The method of claim 72, wherein said linker molecule is a co-polymer of lactic acid.

85. The method of claim 72, wherein said polymer backbone is a hydrophilic polymer.

86. The method of claim 85, wherein said hydrophilic polymer is selected from the group consisting of a natural polysaccharide, a protein, an ethylene glycol based polymer and a propylene glycol based polymer.

87. The method of claim 72, wherein said first polymer backbone is identical to said second polymer backbone.

88. The method of claim 65, wherein said scaffold structure is three dimensional.