180results about How to "Reduce immune rejection" patented technology

Methods and compositions for producing therapeutic agents using chondrocytes are provided. The genetically engineered chondrocytes can be used to express the therapeutic agent in a subject, including in an environment typically associated with chondrocytes and in an environment not typically associated with chondrocytes.

The present invention relates to methods for identifying compounds that can reduce immune rejection, for example, transplant- or autoimmune disorder-related immune rejection. The present invention is based, in part, on the discovery, demonstrated herein, that immune rejection can be monitored by determining the amount of particular members of the Jak/Stat signal transduction pathway present within an affected tissue. The present invention is further based, in part, on the discovery, demonstrated herein, that immune rejection can be reduced and tolerance can be induced by modulating the amount of these particular members of the Jak/Stat signal transduction pathway present, expressed or active within an affected tissue. In particular, the results demonstrate that immune rejection can be monitored by determining the amount of mRNA or protein of Stat1, Stat3, Stat4, Stat6, SOCS1, or SOCS3 present, e.g., in an affected tissue.

The invention provides artificial articular cartilage based on autologous cells and a preparation method thereof. The artificial articular cartilage comprises a nano bionic support and hydrosol adhered to the nano bionic support, wherein one or more cytokines are coated into the hydrosol. The invention also provides the method for preparing the artificial articular cartilage, which comprises the following steps: preparing an electrostatic spinning solution, a cytokine-containing hydrosol solution and a crosslinking agent solution; using the crosslinking agent solution to receive electrostatic spinning so as to prepare the nano bionic support; and using an ink jet printer to print the cytokine-containing hydrosol solution on the nano bionic support, and curing the hydrosol to obtain the artificial articular cartilage. The three-dimensional support adopted by the invention has ideal degradation speed and is degraded after the regeneration of an articular cartilage layer, can meet the requirement of actual clinical application, can be completely degraded, and has good abrasion resistance and lubricity so as to be capable of replacing the cartilage before the regeneration of the articular cartilage layer.

The present invention provides the complete porcine invariant chain protein, full length cDNA, genomic organization, and regulatory region. Methods are provided to prepare organs, tissues, cells and animals lacking the porcine invariant chain gene for use in xenotransplantation.

The invention discloses a 4D-printing shape-memory-polymer-composite-material tracheal stent and a preparing method thereof, and belongs to the technical field of 4D printing. As for the problem thata traditional tracheal stent is difficult to implant, and the secondary stricture problem caused by the overlarge hole diameter of the tracheal stent, and the problem that as the hole diameter of thetracheal stent is over small, swinging of airway cilia is blocked, a compound of a shape memory polymer and nanometer iron oxide serves as a material, a curve-edge rectangle serves as a basic unit, and a tracheal-stent three dimensional structure model is designed; the tracheal-stent three dimensional structure is printed and formed with the fused deposition or direct writing printing method, is subjected to electrostatic spinning medicine carrying covering, and then is subjected to in-vitro remote excitation so that the shape of the stent is recovered, and a formed tracheal stent is obtained.The 4D-printing shape-memory-polymer-composite-material tracheal stent and the preparing method thereof are suitable for production of the tracheal stent.

The success of tissue engineering and therapeutic neovascularization depends on the development of a microvascular network. The present invention provides methods for promoting neovascularization in tissue engineering constructs, tissue repair, and wound healing comprising endothelial and mesenchymal progenitor cells.

The invention discloses a glutathione-modified chitosan copolymer serving as a non-viral gene carrier material and preparation and application thereof, which belong to the fields of gene therapy and novel materials. A preparation method of the copolymer comprises the following steps of: (1) synthesizing an allyl-modified chitosan derivative; (2) synthesizing brush-like PEG (Polyethylene Glycol) polymer chains with different molecular weights through RAFT (Reversible Addition-Fragmentation Chain Transfer); (3) grafting the brush-like PEG onto a chitosan framework by adopting a free radical coupling method; and (4) linking glutathione to the chain end of the brush-like PEG by adopting an EDC (1-Ethyl-3-(3-Dimethyllaminopropyl) Carbodiimide hydrochloride)/NHS (N-hydroxysuccinimide) activation method to obtain a glutathione-modified chitosan copolymer carrier material. The glutathione-modified chitosan copolymer obtained by adopting the technology serves as the non-viral gene carrier material. By adopting the copolymer, the endocytosis function of a composite nanoparticle formed from the copolymer and DNA (Deoxyribonucleic Acid) can be remarkably enhanced, the releasing mechanism of DNA from a composite particle after cell entrance is improved, and the non-viral gene carrier material with a high transfection efficiency is further obtained.

The invention discloses a tissue engineering scaffold material for repairing cartilage defects and a preparation method thereof. The tissue engineering scaffold material is prepared by the following steps of: cleaning the spongy bone at the shoulder blade of a fresh pig; cutting the spongy bone into small blocks with diameter of between 5 and 10mm and thickness of between 3 and 5mm; degreasing, decalcifying and deproteinizing; immersing with alcohol for 30 minutes; and air-drying, wherein the decalcifying time is 6 hours. The prepared demineralized spongy bone matrix (DSBM) has the characteristics of relatively simple and convenient preparation method, and capacity of being obtained on a large scale, can be stored for a long time at a low temperature and is economic and cheap. The material can be prepared into different shapes and sizes according to the shapes of the defects to be repaired, so the material is convenient to apply. The DSBM remains a natural netlike gap structural system of the pig spongy bone, has high cellular compatibility, biocompatibility and degradability and is a very good cartilage tissue engineering scaffold material.

The invention relates to biological ink for 3D printing of artificial skin, and belongs to the technical field of tissue engineering. The biological ink comprises a component A used for constructing an epidermal layer, a component B used for constructing a corium layer and a component C used for constructing an acellular matrix scaffold, wherein the component A comprises first seed cells, first carrier hydrogel and first growth factor slow-release gel containing traditional Chinese medicine components, and the mass ratio of the first carrier hydrogel to the first growth factor slow-release gelis (60: 1)-(60: 8); and the component B comprises second seed cells, second carrier hydrogel and second growth factor slow-release gel. The traditional Chinese medicine components such as dragon's blood and ampelopsis japonica and growth factor slow-release gel are added, and seed cells are extracted from the skin of a patient. The biological ink has good biocompatibility, can effectively promotecell proliferation and regeneration and wound healing, has good mechanical and fluidic properties, and can be used in 3D printing skin and other related fields.

The invention discloses a preparation method of a bionic artificial nerve scaffold established by a collagen. The method comprises the following steps: firstly preparing the collagen in three different shapes for later use: 1) dissolving the frozen and dried collagen by using hexafluoroisopropanol and preparing a nanofiber thin film by using an electrospinning technique; 2) preparing a linear scaffold containing an ordered fine pipeline by the collagen by combining freezing and drying with a mechanical stretching technology; and 3) dissolving the collagen in pure water to prepare a hydrogel; then, coiling the nanofiber thin film into a tube to simulate perilemma, wherein the ordered pipeline linear scaffold is filled in the tube to simulate perineurium; and finally, filling the hydrogel in the pipeline of the linear scaffold and the gap of the scaffold to simulate endoneurium. The bionic artificial nerve scaffold based on a bionic theory better simulates the structure of peripheral nerves and can promote and guide axon and Schwann cells to grow orderly and pass through damaged peripheral nerves based on a good mechanical property.

The invention discloses a dura-mater biological patch and a preparation method thereof. The dura-mater biological patch adopts a process of using small intestinal submucosa tissues as materials and systemically removing immunogenic substances. The preparation method comprises the following steps of: using alcohol to treat and remove lipids, using trypsin and alkali solution to treat and remove cells, using DNA enzyme to treat and remove DNA, and using alpha-galactosidase to treat and remove alpha-Gal antigens and the like. The dura-mater biological patch and the preparation method disclosed by the invention have the advantages that not only can the immunogenic substances be effectively removed, but also the normal structure of extracellular matrix can not be damaged; and when the dura-mater biological patch is clinically applied in repairing dura-mater defects, the leakage of cerebrospinal fluid can be effectively prevented, the tissue can be guided for ingrowth, the tissue growing speed is matched with the patch decomposing speed, the immunological rejection is low and the biocompatibility is good.

The invention discloses a pearl nucleus active liquid used for saltwater pearl culture and a preparation method thereof. In the pearl culture process, by using drug-treated pearl nuclei, immunological rejection on the pearl nuclei after a pearl shell nucleus-implanting operation can be reduced, the migration and the division of small cells are irritated, the formation of pearl sacs is promoted, the wound infection after the operation is reduced, and the goal of comprehensively improving the pearl quality and yield by reducing the nucleus-spitting rate, increasing the thickness of pearl layers and improving the survival rate of cultured pearls is achieved. In the invention, the pearl nucleus active liquid is prepared by utilizing glacial acetic acid, chitosan, tetracycline antibiotics and sterilized filtered seawater. When the pearl nuclei treated by the invention are used for pearl culture, the survival rate of the cultured pearls is increased by 2.59 to 7.33 percent, the pearl-containing rate is increased by 9.8 to 20.07 percent, and the high-quality pearl rate is increased by 5.97 to 12.55 percent.

A biodegradable and bioactive medical tissue adhesive with high bilcompatibility and adjustable mechanical strength and degradating speed for adhering soft tissue and hard tissue is prepared from the liquid phase (hydroxyethyl methylacrylate ring- opening polymerized cycloester type macro-molecular monomer), the alcohol type compound (biodegradable cross-linking agent, vinylpyrrolidone, N,N-dimethyl p- tolueneamine, or hydroquinone), and the solid phase (encapsulated natural powder, pore-forming agent, and benzoly peroxide) through mixing.

A method for preparing PRP (platelet-rich plasma) of umbilical cord blood includes steps: subjecting fresh umbilical cord blood to low-speed centrifuging, removing a lower cell layer, and subjecting upper platelet containing plasma to ultrahigh-speed centrifuging until the liquid is separated into two layers including an upper plasma layer and a lower layer of precipitates which are platelets; removing the upper plasma layer, leaving a small quantity of plasma in an original centrifugal tube, well mixing, vibrating, counting the platelets, and well mixing according to a proportion that 1ml of plasma contains 1.2+/-0.125 billion of platelets approximately. The platelet-rich plasma is effective in treatment of cartilage injuries, pain alleviation and function restoration and especially remarkable in treatment of senile osteoarthritis.

The invention provides sgRNA or PTG (Polycistronic tRNA-gRNA), through combination with a CRISPR-Cas9 technique, a T cell antigen receptor (TCR) can be knocked out, or one or more of genes relevant tomajor histocompatibility complex (MHCI) and immunosuppression molecules can be knocked out. The invention also provides a general type CAR-T cell which can express chimeric antigen receptor (CAR) butcannot express TCR, and a preparation method of the general type CAR-T cell. The general type CAR-T cell prepared by the preparation method is suitable for heterogeneity antigen, has generality and has higher killability at the same time.

Systems and methods for modifying the environment of target cell using genetically altered chondrocytes are provided. The genetically engineered chondrocytes can be used to express a therapeutic agent in a subject, including in an environment typically associated with chondrocytes and in an environment not typically associated with chondrocytes.