Silk fibroin fiber bundles for matrices in tissue engineering
The present invention provides a novel silk-fiber-based matrix having a wire-rope geometry for use in producing a ligament or tendon, particularly an anterior cruciate ligament, ex vivo for implantation into a recipient in need thereof. The invention further provides the novel silk-fiber-based matrix which is seeded with pluripotent cells that proliferate and differentiate on the matrix to form a ligament or tendon ex vivo. Also disclosed is a bioengineered ligament comprising the silk-fiber-based matrix seeded with pluripotent cells that proliferate and differentiate on the matrix to form the ligament or tendon. A method for producing a ligament or tendon ex vivo comprising the novel silk-fiber-based matrix is also disclosed.
1 . A fiber construct comprising sericin-extracted silkworm fibroin fibers, wherein the fibers have a diameter of about 20 to about 40 μm and an average ultimate tensile strength of at least about 0.67 N/fiber.
2 . The fiber construct of claim 1 , wherein the fibers are organized in parallel.
3 . The fiber construct of claim 1 , wherein the fibers are organized in a helical, wire rope, twisted, braided, mesh-like or cabled geometry.
4 . The fiber construct of claim 1 , wherein the fibers comprise a coating and/or surface modification that promotes cellular attachment and/or tissue differentiation and proliferation thereon.
5 . The fiber construct of claim 4 , wherein said coating and/or surface modification comprises an arginine-glycine-aspartate (RGD) peptide.
6 . The fiber construct of claim 4 , wherein said coating and/or surface modification comprises a growth factor.
7 . The fiber construct of claim 1 , wherein the construct comprises a group of at least one to about 1300 fibroin fibers.
8 . The fiber construct of claim 7 , wherein the construct further comprises at least two groups forming a bundle.
9 . The fiber construct of claim 8 , wherein the construct further comprises at least two bundles forming a strand.
10 . The fiber construct of claim 9 , wherein the construct further comprises at least two strands forming a cord.
11 . The fiber construct of claim 7 , wherein the group comprises fibroin fibers organized in a parallel, helical, wire rope, twisted, braided, mesh-like or cabled geometry.
12 . The fiber construct of claim 8 , wherein the bundle comprises groups organized in a parallel, helical, wire rope, twisted, braided, mesh-like or cabled geometry.
13 . The fiber construct of claim 9 , wherein the strand comprises bundles organized in a parallel, helical, wire rope, twisted, braided, mesh-like or cabled geometry.
14 . The fiber construct of claim 10 , wherein the cord comprises strands organized in a parallel, helical, wire rope, twisted, braided, mesh-like or cabled geometry.
15 . The fiber construct of claim 1 , wherein the construct has an average ultimate tensile strength of at least about 6.67 N.
16 . The fiber construct of claim 1 , further comprising cells.
17 . The fiber construct of claim 16 , wherein the cells are selected from the group consisting of stem cells, muscle cells, bone marrow stromal cells, pluripotent cells, or fibroblast cells.
18 . A method for producing a sericin-extracted silk-fibroin fiber construct comprising: contacting at least one silkworm fibroin fiber with an aqueous solution of Na 2 Co 3 and detergent to extract sericin from the fiber.
19 . A method for producing a sericin-extracted silk-fibroin fiber construct comprising:
a. arranging at least 2 silkworm fibroin fibers to form a group; and
b. contacting the group with an aqueous solution of Na 2 Co 3 and detergent to extract sericin from the fibers.
20 . A method for producing a sericin-extracted silk-fibroin fiber construct comprising:
a. arranging at least 2 groups of silkworm fibroin fibers to form a bundle; and
b. contacting the bundle with an aqueous solution of Na2Co3 and detergent to extract sericin from the fibers.
21 . A method for producing a sericin-extracted silk-fibroin fiber construct comprising:
a. arranging at least 2 bundles of silkworm fibroin fibers to form a strand; and
b. contacting the strand with an aqueous solution of Na2Co3 and detergent to extract sericin from the fibers.
22 . A method for producing a sericin-extracted silk-fibroin fiber construct comprising:
a. arranging at least 2 strands of silkworm fibroin fibers to form a cord; and
b. contacting the cord with an aqueous solution of Na2Co3 and detergent to extract sericin from the fibers.
23 . The method as in one of claims 18 - 22 , wherein the sericin is extracted at a temperature no greater than about 90° C.
24 . The method as in one of claims 18 - 22 , further comprising the step of coating the fibroin fibers with a coating and/or surface modifier that promotes cellular attachment and/or tissue proliferation on the fibers.
25 . The method of claim 24 , wherein said coating and/or surface modifier comprises an arginine-glycine-aspartate (RGD) peptide.
26 . The method of claim 24 , wherein said coating and/or surface modifier comprises a growth factor.
27 . The method of claim 19 , wherein said group comprises up to 1300 fibroin fibers.
28 . The method of claim 18 , further comprising the step of placing the fiber in a twisted, helical, braided, mesh-like or cabled geometry.
29 . The method of claim 19 , wherein the fibers are organized in a parallel, helical, wire rope, twisted, braided, mesh-like or cabled geometry.
30 . The method of claim 20 , wherein the groups are organized in a parallel, helical, wire rope, twisted, braided, mesh-like or cabled geometry forming a bundle.
31 . The method of claim 21 , wherein the bundles are organized in a parallel, helical, wire rope, twisted, braided, mesh-like or cabled geometry forming a strand.
32 . The method of claim 22 , wherein the strands are organized in a in parallel, helical, wire rope, twisted, braided, mesh-like or cabled geometry forming a cord.
33 . The method as in any of claims 18 - 22 , further comprising:
a. contacting the construct with cells; and
b. culturing the construct under conditions suitable for cell growth and regeneration.
34 . The method of claim 33 , wherein the cells are stem cells, muscle cells, bone marrow stromal cells, pluripotent cells, or fibroblast cells.