2682 results about "Tissue engineering" patented technology

The present patent describes a biocompatible composite made of a first fibrous layer attached to a three-dimensional inter-connected open cell porous foams that have a gradient in composition and / or microstructure through one or more directions. These composites can be made from blends of absorbable and biocompatible polymers. These biocompatible composites are particularly well suited to tissue engineering applications and can be designed to mimic tissue transition or interface zones.

A freeze dried biocompatible matrix comprising plasma proteins, useful as implants for tissue engineering as well as in biotechnology, and methods of producing the matrix are provided. Mechanical and physical parameters can be controlled by use of auxiliary components or additives which may be removed after the matrix is formed in order to improve the biological properties of the matrix. The matrices according to the present invention may be used clinically per se, or as a cell-bearing implant.

A family of selectively absorbable / biodegradable, fibrous composite constructs includes different combinations of biostable and absorbable / biodegradable yarns assembled as initially interdependent, load-bearing components, transitioning to exhibit independent functional properties during in vivo end-use. The family of constructs consists of two groups, one group is made of fiber-reinforced composites of high compliance, absorbable matrices of segmented polyaxial copolyesters reinforced with multifilament yarn constructs, which are combinations of ultrahigh molecular weight polyethylene fibers and at least one absorbable / biodegradable fiber selected from silk fibers and multifilament yarns made from linear segmented, l-lactide copolyesters and poly (3-hydroxyalkanoates, are useful in orthopedic, maxillofacial, urological, vascular, hernial repair and tissue engineering applications. The second group is made of coated and uncoated, warp-knitted mesh constructs for use in hernial, vascular, and urological tissue repair and tissue engineering.

Polymeric delivery devices have been developed which combine high loading / high density of molecules to be delivered with the option of targeting. As used herein, “high density” refers to microparticles having a high density of ligands or coupling agents, which is in the range of 1000-10,000,000, more preferably between 10,000 and 1,000,000 ligands per square micron of microparticle surface area. A general method for incorporating molecules into the surface of biocompatible polymers using materials with an HLB of less than 10, more preferably less than 5, such as fatty acids, has been developed. Because of its ease, generality and flexibility, this method has widespread utility in modifying the surface of polymeric materials for applications in drug delivery and tissue engineering, as well other other fields. Targeted polymeric microparticles have also been developed which encapsulate therapeutic compounds such as drugs, cellular materials or components, and antigens, and have targeting ligands directly bound to the microparticle surface. Preferred applications include use in tissue engineering matrices, wound dressings, bone repair or regeneration materials, and other applications where the microparticles are retained at the site of application or implantation. Another preferred application is in the use of microparticles to deliver anti-proliferative agents to the lining of blood vessels following angioplasty, transplantation or bypass surgery to prevent or decrease restenosis, and in cancer therapy. In still another application, the microparticles are used to treat or prevent macular degeneration when administered to the eye, where agents such as complement inhibitors are administered.

The invention relates to methods and compositions for the differentiation of stromal cells from adipose tissue into hematopoietic supporting stromal cells and myocytes of both the skeletal and smooth muscle type. The cells produced by the methods are useful in providing a source of fully differentiated and functional cells for research, transplantation and development of tissue engineering products for the treatment of human diseases and traumatic tissue injury repair.

Tissue engineering devices for use in the repair or regeneration of tissue made of support scaffolds and cell sheets.

Methods and devices for transmitting micromechanical forces locally to induce surface convolutions into tissues on the millimeter to micron scale for promoting wound healing are presented. These convolutions induce a moderate stretching of individual cells, stimulating cellular proliferation and elaboration of natural growth factors without increasing the size of the wound. Micromechanical forces can be applied directly to tissue, through biomolecules or the extracellular matrix. This invention can be used with biosensors, biodegradable materials and drug delivery systems. This invention will also be useful in pre-conditioned tissue-engineering constructs in vitro. Application of this invention will shorten healing times for wounds and reduce the need for invasive surgery.

The present invention relates to orthopaedic implants having a fenestrated hollow shell and a biologic core. These design features provide an improved interface between the implant and the surrounding tissue, aiding fixation, and provide a vehicle for applying new bone healing and enhancing modalities, such as gene therapy, tissue engineering, and growth factors.

Crosslinked compositions formed from water-insoluble copolymers are disclosed. These compositions are copolymers having a bioresorbable region, a hydrophilic region and at least two cross-linkable functional groups per polymer chain. Crosslinking of these polymers can be effected in solution in organic solvents or in solvent-free systems. If crosslinking occurs in a humid environment, a hydrogel will form. If crosslinking occurs in a non-humid environment, a xerogel will form which will form a hydrogel when exposed to a humid environment and the resulting crosslinked materials form hydrogels when exposed to humid environments. These hydrogels are useful as components in medical devices such as implantable prostheses. In addition, such hydrogels are useful as delivery vehicles for therapeutic agents and as scaffolding for tissue engineering applications.

A nanofibrillar structure for cell culture and tissue engineering is disclosed. The nanofibrillar structure can be used in a variety of applications including methods for proliferating and / or differentiating cells and manufacturing a tissue. Also disclosed is an improved nanofiber comprising a lipid, lipophilic molecule, or chemically modified surface. The nanofibers can be used in a variety of applications including the formation of nanofibrillar structures for cell culture and tissue engineering.

A process and apparatus are provided for manufacturing complex parts and devices which utilize a CAD environment to design a part or device to be created (FIG. 1); Boolean, scaling, smoothing, mirroring, or other operations to modify the CAD design; a software interface to convert the CAD designed part (Data Process System) or device into a heterogeneous material and multi-part assembly model (Design Input Model) which can be used for multi-nozzle printing; and a multi-nozzle system to print the designed part or device using different, specialized nozzles (Tissue substitutes).

Polymeric microparticles have been developed which encapsulate therapeutic compounds such as drugs, cellular materials or components, and antigens, and can have targeting ligands directly bound to the microparticle surface. Preferred applications include use in tissue engineering matrices, wound dressings, bone repair or regeneration materials, and other applications where the microparticles are retained at the site of application or implantation. Another preferred application is in the use of microparticles to deliver anti-proliferative agents to the lining of blood vessels following angioplasty, transplantation or bypass surgery to prevent or decrease restenosis, and in cancer therapy. In still another application, the microparticles are used to treat or prevent macular degeneration when administered to the eye, where agents such as complement inhibitors are administered.

The present invention relates generally to the utilization of in situ polymers or copolymers to form a porous microcellular scaffold for the delivery, attachment, housing, protection, multiplication and growth of encapsulated cells. More particularly, the present invention relates to cells delivered using such a scaffold to augment, repair or replace in vivo diseased, damaged or otherwise compromised tissues or organs of a living body.

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.

The present invention relates to biocompatible, biodegradable polyurethane / urea polymeric compositions that are capable of in-vivo curing with low heat generation to form materials suitable for use in scaffolds in tissue engineering applications such as bone and cartilage repair. The polymers are desirably flowable and injectable and can support living biological components to aid in the healing process. They may be cured ex-vivo for invasive surgical repair methods, or alternatively utilized for relatively non-invasive surgical repair methods such as by arthroscope. The invention also relates to prepolymers useful in the preparation of the polymeric compositions, and to methods of treatment of damaged tissue using the polymers of the invention.

The present invention provides a polyurethane or polyurethane / urea composition which has a tensile strength greater than 10 MPa, a modulus of elasticity greater than 400 MPa and an elongation at break greater than 30% at a temperature of between 0° C. and 60° C. and at a relative humidity of between 0% and 100%.The invention further provides uses of the compositions of the invention in biomedical vascular stents, an orthopaedic implant, a drug delivery coating or in tissue engineering.

Polymeric nanofibers have been developed which are useful in a variety of medical and other applications, such as filtration devices, medical prosthesis, scaffolds for tissue engineering, wound dressings, controlled drug delivery systems, cosmetic skin masks, and protective clothing. These can be formed of any of a variety of different polymers, either non-degradable or degradable. In a preferred embodiment demonstrated in the following examples, nanofibers are formed of biodegradable and non biodegradable polyphosphazenes, their blends with other polyphosphazenes or with organic, inorganic / organometallic polymers as well as composite nanofibers of polyphosphazenes with nanosized particles such as hydroxyapatites.

The present specification provides for methods for purifying fibroins, purified fibroins, methods of conjugating biological and synthetic molecules to fibroins, fibroins conjugated to such molecules, methods of making fibroin hydrogels, fibroin hydrogels and fibroin hydrogel formulations useful for a variety of medical uses, including, without limitation uses as bulking agents, tissue space fillers, templates for tissue reconstruction or regeneration, cell culture scaffolds for tissue engineering and for disease models, surface coating to improve medical device function, or drug delivery devices.

This invention relates to biocompatible, biodegradable thermoplastic polyurethane or polyurethane / ureas comprising isocyanate, polyol and a conventional chain extender and / or a chain extender having a hydrolysable linking group and their use in tissue engineering and repair applications, particularly as stents and stent coating.

The present specification provides for methods for purifying fibroins, purified fibroins, methods of conjugating biological and synthetic molecules to fibroins, fibroins conjugated to such molecules, methods of making fibroin hydrogels, fibroin hydrogels and fibroin hydrogel formulations useful for a variety of medical uses, including, without limitation uses as bulking agents, tissue space fillers, templates for tissue reconstruction or regeneration, cell culture scaffolds for tissue engineering and for disease models, surface coating to improve medical device function, or drug delivery devices.

A composite product is disclosed as a collagen support comprising at least one porous collagen layer covered on at least one side with an essentially compact collagen membrane consisting either of a collagen film prepared by drying a collagen gel, preferably in air or a gaseous fluid, or of a very highly compressed collagen sponge. At least one of the two layers, i.e. the porous layer and the essentially compact membrane, may comprise normal, genetically modified or malignant living cells originating particularly from young or elderly subjects. This composite product is used as a collagen support for the manufacture of artificial skin intended especially for performing in vitro tests on the efficacy of potentially active substances or for reconstructing damaged areas of skin in vivo.

The present invention refers to a three-dimensional porous hybrid scaffold for tissue engineering and methods of its manufacture and use.

Absorbable polyurethanes, polyamides and polyester urethanes prepared from at least one compound selected from: or the diamines and diisocyanates thereof, wherein each X represents a member independently selected from —CH2COO— (glycolic acid moiety), —CH(CH3)COO— (lactic acid moiety), —CH2CH2OCH2COO— (dioxanone), —CH2CH2CH2CH2CH2COO— (caprolactone moiety), —(CH2)yCOO— where y is one of the numbers 2, 3, 4 or 6-24 inclusive, and —(CH2CH2O)z′CH2COO— where z′ is an integer between 2 and 24, inclusive; each Y represents a member independently selected from —COCH2O— (glycolic ester moiety), —COCH(CH3)O— (lactic ester moiety), —COCH2OCH2CH2O— (dioxanone ester), —COCH2CH2CH2CH2CH2O— (caprolactone ester), —CO(CH2)mO— where m is an integer between 2, 3, 4 or 6-24 inclusive, —COCH2O(CH2CH2O)n— where n is an integer between 2 and 24, inclusive; R′ is hydrogen, benzyl or an alkyl group, the alkyl group being either straight-chained or branched; p is an integer between 1 and 4, inclusive; and Rn represents one or more members selected from H, alkoxy, benzyloxy, aldehyde, halogen, carboxylic acid and —NO2, which is attached directly to an aromatic ring or attached through an aliphatic chain. Absorbable polymers prepared from these compounds are useful for drug delivery, tissue engineering, tissue adhesives, adhesion prevention and other implantable medical devices.

The invention provides tissue engineering compositions and methods wherein three-dimensional matrices for growing cells are prepared for in vitro and in vivo use. The matrices comprise biodegradable polymer fibers capable of the controlled delivery of therapeutic agents. The spatial and temporal distribution of released therapeutic agents is controlled by use of defined nonhomogeneous patterns of therapeutic agents in the matrices.

The invention provides a self-assembling peptide comprising (a) a first amino acid domain that mediates self-assembly, wherein the domain comprises alternating hydrophobic and hydrophilic amino acids that are complementary and structurally compatible and self-assemble into a macroscopic structure when present in unmodified form; and (b) a second amino acid domain that does not self-assemble in isolated form. In certain embodiments of the invention the second amino acid domain comprises a biologically active peptide motif, e.g., a peptide motif found in a naturally occurring protein, or a target site for an interaction with a biomolecule. In certain embodiments of the invention the naturally occurring protein is a component of the extracellular matrix, e.g., a component of the basement membrane. The invention further provides scaffolds comprising the self-assembling peptides and methods of using the scaffolds including for cell culture, tissue engineering, and tissue repair.