Graft for directed vascular and lymphatic regeneration and methods to guide endothelial cell assembly
View Patent ↗Embodiments of the present invention relate to a therapeutic device (graft) comprising a collagen membrane having an aligned uniaxial or biaxial structure such that mammalian cells plated on the membrane align mainly along the direction of the collagen fibrils. In a further aspect, a graft comprising a substantially tubular body, wherein the body has an exterior surface, an interior surface, and at least one lumen extending therethrough such that a fluid flow through the lumen can direct mammalian cell migration. In a further aspect, mammalian cells or growth and angiogenic factors can be optionally attached to the exterior and/or interior surface of the substantially tubular body. In various aspects, the graft can be used as a vascular prosthesis, a stent, or a nerve regeneration scaffold. Methods of preparing and implanting same are also provided.
1. A graft comprising: a collagen membrane comprised of crimped collagen fibrils such that the membrane has an aligned uniaxial or biaxial structure and more than 50% of mammalian fibroblasts plated on the membrane align parallel to the direction of the collagen fibrils, wherein the membrane guides endothelial cell assembly parallel to the alignment direction which diminishes adherence of monocytes in comparison with adherence to endothelial cells plated on a membrane with random fibril orientation.
2. A graft according to claim 1 , where the graft further comprises a collagen membrane having an aligned-crimped structure which exhibit a crimp pattern, such that more than 50% of mammalian fibroblasts plated on the membrane align perpendicular to ridges and grooves of the crimp pattern and parallel to the direction of the crimped fibrils.
3. A graft according to claim 1 , wherein the membrane has a transmission diffraction pattern produced by a laser source with wavelength in the visible range, such that the pattern has at least two centrally symmetric elongated “petals”.
4. A graft according to claim 1 , wherein more than 50% of the collagen fibrils have a diameter in the range from 20 nm to 60 nm.
5. A graft according to claim 1 , wherein the membrane is rolled and folded in a thread-like construct such that an alignment direction of the membrane is oriented along the thread-like construct, wherein the construct is further cross-linked and has viscoelastic properties under uniaxial load.
6. A graft according to claim 5 , wherein the thread-like construct has at least one cavity elongated substantially along the construct suitable for carrying cells, growth factors, drugs, other suitable bioactive materials and cell formations like endothelial spheroids and islets.
7. A graft according to claim 6 , wherein the cells are selected from the group consisting of myocyte precursor cells, smooth muscle cells, cardiac myocytes, skeletal myocytes, satellite cells, fibroblasts, cardiac fibroblasts, chondrocytes, osteoblasts, osteocytes, endothelial cells, epithelial cells, epidermal cells, embryonic stem cells, hemopoietic cells, neuronal cells, Schwann cells, mesenchymal stem cells, glial cells, dorsal root ganglia, anchorage-dependent cell precursors, or combinations thereof.
8. A graft according to claim 5 , wherein the thread-like construct has a multi-luminal nodular compartment suitable for embedding thymus derived stromal cells and bone marrow derived dendritic cells to generate a lymph node-like immune response function, and the flanking thread-like sections with no or single lumen suitable to carry and align endothelial cells to integrate the lymph node prosthesis into lymphatic system and link it to the blood circulation.
9. A graft according to claim 5 , wherein the thread-like construct has multi-luminal structure with crimped fibrils align along its length and multiple lumens within the construct running parallel with the construct length, but start and stop at various places along the construct.
10. A graft according to claim 5 , wherein the construct has diameter ranges from 50 μm to 2 mm in a dry state and tensile strength is higher than 0.2 MPa in the wet state.
11. A graft according to claim 5 , wherein the construct has Fung-elastic material properties after precondition to a load pattern with the constant A ranging from 0.2 MPa to 300 MPa and constant B ranging from 0.5 MPa to 200 MPa when measured in the wet state.
12. A graft according to claim 5 , wherein the construct promotes angiogenesis, vascularization and serves as means for guiding migration and orientation of endothelial cells along the alignment direction, as well as the cell localization.
13. A graft according to claim 5 comprising a substantially tubular body, wherein the body has an exterior surface, an interior surface, and at least one lumen extending therethrough such that a fluid flow through the lumen can direct endothelial cell migration.
14. A graft according to claim 5 or 13 , wherein the construct promotes directed vascular or lymphatic regeneration along the alignment direction.
15. A graft according to claim 13 , wherein the exterior surface has aligned-crimped structure and the interior surface has aligned-crimped structure such that the alignment directions of the exterior and interior surfaces form non-zero angle.
16. A graft according to claim 15 , wherein the angle is the 90° angle and the alignment direction of the crimped fibrils of the interior surface coincides with the direction of at least one lumen.
17. A graft according to claim 1 or 5 , wherein the membrane guides endothelial cell assembly along the alignment direction and extends the survival of cells in ischemic tissue.
18. A graft according to claim 1 or 5 , wherein the membrane is formed of at least one or more type of collagens: I, II, III, IV, V, VI or XI.
19. A graft according to claim 5 , wherein at least one thread-like construct is attached to a carrier with lymph node or lymph node fragment or mammalian decellularized lymph node and prepared for transferring or transplanting a graft in a mammalian subject by catheter, trocar, or other minimally invasive procedure, wherein the construct promotes survival of the lymph node and integration of the lymph node into a lymphatic network in the mammalian subject, at the site of transfer or transplantation.
20. A graft comprising: a multilayer collagen membrane with a top layer having collagen fibrils in an aligned-crimped structure and a bottom layer having collagen fibrils in an aligned-crimped structure such that the alignment directions of the top and bottom layers form an angle, wherein more than 50% of the mammalian cells that are plated on the membrane align perpendicular to ridges and grooves of the crimp pattern and parallel to the direction of the crimped fibrils in each layer, wherein the cells are selected from the group consisting of myocyte, smooth muscle cells, cardiac myocytes, fibroblasts, endothelial cells, neuronal cells, mesenchymal stem cells, or combinations thereof and wherein at least one membrane is comprised of more than 50% of collagen fibrils with diameter in range from 20 nm to 60 nm.
21. The graft according to claim 1 , 5 or 20 , wherein it further comprises growth factors, peptides, elastin, fibrin, heparin, proteoglycans, glycoproteins, hyaluronan, cross-linking agents, or combinations thereof.