153results about How to "Low immunogenicity" patented technology

The invention relates to the field of biomedical materials, in particular to a novel composite collagen material for wound repair, and particularly relates to a preparation method of the novel composite collagen material containing 21-type recombinant humanized collagen (ColpepA1 21) and application of the novel composite collagen material in wound repair. The ColpepA1 21 is used for remarkably promoting key biological reactions in the wound healing process, including accelerating cell migration, enhancing the skin hydration state and barrier function and improving the stability and elasticity of the skin structure, a novel composite collagen material is developed, wound healing and cell regeneration can be effectively promoted, and oxidative damage can be relieved.

The invention belongs to the field of molecular biology and immunology, and particularly relates to an anti-CD3 nano antibody capable of activating the activity of T cells as well as a preparation method and application of the anti-CD3 nano antibody. The invention provides a preparation method of the anti-CD3 nano antibody. The preparation method comprises the following steps: constructing a CD3 plasmid and an overexpression cell line, and immunizing alpaca to obtain peripheral blood mononuclear cells (PBMC) of the alpaca; extracting RNA (Ribonucleic Acid) and carrying out reverse transcription to obtain cDNA; carrying out PCR amplification on the antibody gene segment and cloning the antibody gene segment to a phage display vector; and electrically transforming the vector into SS320 competent cells to obtain the nano antibody library. After two rounds of panning, detecting and screening an antibody clone capable of being combined with the CD3 protein through ELISA (Enzyme-Linked Immunosorbent Assay); an antibody sequence is selected through sequencing, and an antibody protein is expressed by using a mammalian cell high-throughput expression system; and then detecting and screening the antibody which is only specifically combined with the CD3. The method disclosed by the invention is simple, convenient and rapid to operate, and can be used for preparing active antibodies for treating potential tumors and proliferative diseases.

The invention relates to a humanized nano antibody targeting cadherin 17 and application of the humanized nano antibody, and relates to the technical field of immunology and molecular biology. The complementarity determining region of the humanized nano antibody comprises a CDR1 of which the amino acid sequence is shown as SEQ ID NO: 2, a CDR2 of which the amino acid sequence is shown as SEQ ID NO: 4 and a CDR3 of which the amino acid sequence is shown as SEQ ID NO: 6; a framework region of the humanized nano antibody comprises an FR1 of which the amino acid sequence is shown as any one of SEQ ID NO: 1 and SEQ ID NO: 8, an FR2 of which the amino acid sequence is shown as any one of SEQ ID NO: 3, SEQ ID NO: 9 and SEQ ID NO: 11, an FR3 of which the amino acid sequence is shown as any one of SEQ ID NO: 5 and SEQ ID NO: 10, and an FR4 of which the amino acid sequence is shown as SEQ ID NO: 7. According to the humanized nano-antibody, the immunogenicity of the nano-antibody is reduced, the targeted binding activity and killing activity are improved, and the humanized nano-antibody can be used for developing immunodetection reagents, CAR-T / NK cell drugs and antibody drugs.

The invention provides a recombinant XVII type collagen with a triple helix structure, and belongs to the technical field of biological proteins. The amino acid sequence of the collagen comprises one or more amino acid residue repetitive units, each repetitive unit comprises a sequence as shown in SEQ ID NO.1 or SEQ ID NO.2, the number of repetitions is n, and n is larger than 1 and smaller than or equal to 60. The recombinant XVII type collagen provided by the invention is simple in production process, relatively high in expression quantity, low in immunogenicity, high in safety, relatively good in stability of the triple-helix structure, and strong in supporting capacity for skin cells; efficacy experiments show that the collagen has higher cell adhesion, wound healing promotion and hair follicle repair promotion capability than XVII type collagen products in the market at present, and can be widely applied to the fields of food, health care products, cosmetics, medical instruments and the like.

The invention discloses a preparation method and application of a manganese-based amino acid coordination polymer, and belongs to the technical field of nano-enzymes and nano-drugs. Divalent manganese salt, histidine and other amino acids are subjected to a co-precipitation reaction to prepare the manganese-based amino acid coordination polymer, and the polymer is of a nanoparticle structure, small in size and high in stability, has enzyme-like activity, catalyzes hydrogen peroxide to generate high-toxicity hydroxyl free radicals and is used for specifically killing tumor cells. The catalyst has the capability of catalytically generating singlet oxygen in the presence of hydrogen peroxide. Meanwhile, the manganese-based amino acid complex has glutathione oxidase-like activity, consumes glutathione to overcome the resistance of tumors to oxidative stress, improves the chemical kinetic curative effect, and has anti-tumor application potential.

The invention relates to the technical field of medicine, and discloses an artificial exosome and application thereof in drug delivery, the artificial exosome is prepared into an oil phase based on PLGA and DOTAP, and a water phase based on OCT4 protein and siTrim28; mixing the two phases to obtain a primary emulsion, and adding a PVA aqueous solution to obtain a double emulsion; stirring the double emulsion and volatilizing the solvent to form an emulsified solution, and centrifuging to obtain PLGA nanoparticles; the lipid mixture is prepared from lipid, DPPE-PEG2000, alpha-tocopherol and alpha-lactalbumin, and a lipid film is formed after a solvent is evaporated; the preparation method comprises the following steps: mixing PLGA nanoparticles, a lipid film and membrane protein, uniformly mixing and heating to obtain a film-coated solution, and finally extruding through a cellulose acetate film to obtain the artificial exosome. The artificial exosome disclosed by the invention combines the stability of the PLGA nanoparticles and the biocompatibility of the lipid membrane, and provides new possibility for a drug delivery system.

The invention belongs to the technical field of molecular biology and immunology, and provides an alpaca-derived nano antibody specifically bound with a simian vacuolar virus 40 large T antigen SV40LTA and application of the alpaca-derived nano antibody. The invention relates to a heavy chain antibody, which has a heavy chain variable region VHH, the VHH comprises the following CDR: CDR1 with an amino acid sequence as shown in SEQ ID NO: 1, CDR2 with an amino acid sequence as shown in SEQ ID NO: 2, and CDR3 with an amino acid sequence as shown in SEQ ID NO: 3, the VHH comprises four frame regions of FR1-4, and FR1, FR2, FR3 and FR4 and CDR1, CDR2 and CDR3 are arranged in a staggered manner in sequence. The antibody is high in neutralizing activity and strong in binding capacity with SV40LTA, and the equilibrium dissociation constant is less than 0.1 nM; the monoclonal antibody has the advantages that the monoclonal antibody can effectively recognize SV40LTA, the molecular weight is small, the immunogenicity is small, the solubility and stability are better, and the CDR region is longer; and a potential application value is provided for SV40LTA detection.

The invention belongs to the technical field of gene engineering and biology, discloses a modified adeno-associated virus AAV-8 serotype for retina wide targeting and expression, and further relates to construction and application of the modified type. 10 amino acid sequences as shown in SEQ ID NO.3 are inserted between the 590th amino acid and the 591th amino acid of an AAV-8 serotype capsid protein sequence as shown in SEQ ID NO.2, the first, second and tenth amino acids are protected amino acids, and the third to ninth amino acids are amino acid sequences obtained by screening. The modified serotype disclosed by the invention is stronger in fluorescence effect after infection and can be obviously and intuitively observed, an exogenous gene can be widely and efficiently expressed in a specific targeted tissue retina whole region, and the expression efficiency is greatly improved under the condition of using the same virus amount. And compared with a wild serotype, the serotype has better and wider targeted tissue expression and less non-targeted tissue expression.

The invention discloses a device and a method for designing a humanized antibody based on CDR transplantation, and a computer readable storage medium. The method comprises the following steps: replacing an antigen complementarity determining region sequence of a humanized antibody sequence with an antigen complementarity determining region sequence of a target antigen heterologous antibody to obtain a CDR region transplantation antibody; the method comprises the following steps: performing single amino acid reverse mutation on different amino acid sites of a CDR region transplantation antibody and a heterologous antibody, and comparing structural difference scores of protein three-dimensional structures before and after mutation; retaining the single amino acid reverse mutation site with the structural difference score less than or equal to 1, and finally obtaining the CDR transplanted humanized antibody of the target antigen. According to the method, the similarity of heterologous antibody and human antibody sequences can be increased, the immunogenicity of the target antigen human antibody is reduced, and the affinity is maintained.

The invention discloses a recombinant VI-type collagen as well as a preparation method and application thereof. The recombinant VI-type collagen comprises a protein gene segment derived from a natural VI-type collagen alpha2 chain, and proteins P0607, P060702 and / or P060703 capable of promoting cartilage cell proliferation activity are expressed. Gene segments derived from a natural type VI collagen alpha2 chain are integrated through a genetic engineering means, sequence optimization and repetition are carried out on the gene segments to enhance the biological activity of the collagen, the recombinant type VI collagen P0607, P060702 and P060703 can be stably and efficiently produced, the recombinant collagen has the effect of promoting chondrocyte proliferation, and the recombinant collagen can be applied to the field of cartilage cell proliferation. An efficient and reliable biological manufacturing way is provided for research, development and production of osteoarthritis medicines.

The invention discloses a gene engineering exosome and a slow release method and application thereof, the gene engineering exosome is derived from human adipose-derived stem cells, si-tgfbr2 is loaded in the gene engineering exosome, the si-tgfbr2 is specific siRNA aiming at a Tgfbr2 gene, and the gene engineering exosome can regulate and control proliferation of VSMCs, inhibit transformation of the VSMCs from a contraction phenotype to a synthetic phenotype when the VSMCs are stimulated, and inhibit the growth of the VSMCs. According to the present invention, the gene engineering exosome can be used to maintain the normal structure and the function of the blood vessel, and the sustained release effect of the content in the gene engineering exosome can be achieved by wrapping the gene engineering exosome in the PHA biodegradable material, such that the local treatment concentration can be easily stabilized, the drug administration frequency can be easily reduced, the lasting time of the treatment effect can be easily prolonged, and the treatment gene can be effectively delivered to the target cell; the treatment effect is improved; when being used for modifying a small-caliber artificial blood vessel, the small-caliber artificial blood vessel can be improved in biocompatibility and functionality, and can be prevented from being implanted into the blood vessel for remodeling unbenign hyperplasia stenosis; the invention not only provides a new thought and method for the treatment of vascular diseases, but also has important clinical application value and popularization prospect.

The invention discloses a drug-guided anti-inflammatory enhanced mesenchymal stem cell preparation as well as a preparation method and application thereof. By constructing the medicine-loaded mesenchymal stem cell preparation, the immunosuppression capacity of the mesenchymal stem cells is improved, the angiogenesis capacity of the mesenchymal stem cells is reduced, meanwhile, by releasing the glucocorticoid medicine at a low dosage, the side effect of single administration is avoided, M2 type macrophage polarization is induced, the inflammatory state of cartilage cells is improved, and the effect of treating the cartilage cells is achieved. The curative effect of the mesenchymal stem cells on osteoarthritis is improved in multiple aspects, and the mesenchymal stem cells are proved in animal bodies. The drug-guided anti-inflammatory enhanced mesenchymal stem cell preparation provides a new thought for the treatment of osteoarthritis.

The invention relates to the technical field of tissue engineering, and particularly discloses preparation of an exosome and electrostatic spinning composite material for promoting bone regeneration and application of the exosome and electrostatic spinning composite material in bone tissue regeneration. Identifying the multiplication capacity, the surface marker and the multidirectional differentiation capacity of the cells after the cells are separated and cultured, and finally extracting and identifying the exosome; pLLA and gelatin are dissolved in a cosolvent trifluoroethanol, composite fibers are prepared through electrostatic spinning, and a composite fiber membrane is obtained through spinning by adopting a receiver; the exosome is loaded on the surface of the PLLA / gelatin composite fiber membrane. According to the invention, the exosome derived from human mesenchymal stem cells is combined with the membrane material to prepare the exosome capable of stably releasing, the good stability and low immunogenicity of the exosome are exerted, and the effect of accurately promoting local bone regeneration is realized. And defect repair and functional reconstruction are realized.

The invention belongs to the field of biotechnology, and specifically relates to a mouse-derived anti-swine IgA single-chain antibody and an application thereof. The single-chain antibody comprises a heavy chain variable region and a light chain variable region, the amino acid sequence of the heavy chain variable region is shown in SEQ ID No.1, and the amino acid sequence of the light chain variable region is shown in SEQ ID No.3. The gene sequence of the mouse-derived antibody variable region is compared with the gene sequence of the prepared single-chain antibody, and the result shows that the gene sequence of the single-chain antibody is basically consistent with the gene sequence of the mouse-derived antibody variable region, proving that the constructed antibody gene sequence is correct. The single-chain antibody fills the gap of the anti-swine IgA single-chain antibody on the current market, provides new materials for the early diagnosis and prevention and control of pig-derived IgA antibodies, and provides new technical support for controlling the epidemic spread of pig diarrhea diseases as soon as possible.

The invention belongs to the technical field of monoclonal antibody preparation, and particularly relates to a human-mouse chimeric monoclonal antibody for resisting human myelin sheath oligodendrocyte glycoprotein (MOG) and application of the human-mouse chimeric monoclonal antibody. Complementary determining regions in variable regions of a heavy chain and a light chain of the human-mouse chimeric monoclonal antibody of the anti-human MOG protein come from a mouse, parent activity is reserved to the maximum extent, a constant region is a human antibody constant region, immunogenicity is greatly reduced due to introduction of the human antibody constant region, the occurrence probability of a human anti-mouse antibody reaction is reduced, and the anti-human MOG protein is prepared. The specificity of the antibody is improved. The human-mouse chimeric monoclonal antibody resisting the human MOG protein has antigen binding specificity, the heterology of a mouse monoclonal antibody is greatly reduced, the biological activity of the human-mouse chimeric monoclonal antibody is good, and the human-mouse chimeric monoclonal antibody resisting the human MOG protein can specifically detect the MOG protein.

The invention belongs to the technical field of biological medicine, and provides an engineered extracellular vesicle, a preparation method, application and a drug for targeted repair of blood brain barrier in order to solve the technical problems that an existing repair tool takes effect slowly and is not enough in specificity, and the engineered extracellular vesicle is loaded with Wnt7a-K190A protein. After entering the brain, the engineered extracellular vesicle can be rapidly and specifically combined with a Gpr124 receptor to promote blood brain barrier repair, and in-vivo experiments verify that the engineered extracellular vesicle can promote blood brain repair, so that the engineered extracellular vesicle can be applied to preparation of targeted blood brain barrier repair drugs, becomes a supplement of existing tools, AAV, LNP and the like, and has a wide application prospect. Particularly, the high requirement on the treatment timeliness of central nervous system (injury irreversibility) diseases is met.

The invention discloses a method for preparing RNA (Ribonucleic Acid) through in-vitro transcription and application. The method comprises the following steps: (1) preparing a linearized DNA template; (2) constructing an in-vitro transcription reaction system, and performing in-vitro transcription under a reaction condition suitable for transcription; and (3) purifying the prepared mRNA. According to the method, RNA polymerase can reduce 3 '-extension and non-specific transcription initiation of an IVT product under the condition that the temperature is increased, and an appropriate amount of L-arginine or salt thereof is added into a reaction system, so that the RNA structure can be effectively prevented from being damaged while the mRNA yield is not reduced, and the generation of dsRNA is further reduced. In addition, the reduction of dsRNA can significantly reduce the immunogenicity of mRNA.

The invention relates to the technical field of antioxidant peptides, in particular to an antioxidant peptide HYHE derived from dietary protein and application of the antioxidant peptide HYHE. The amino acid sequence of the antioxidant peptide is HYHE and is as shown in SEQ ID NO: 1. The antioxidant peptide is obtained based on prediction of an antioxidant peptide prediction platform Pred5AOP; 27 dietary proteins are virtually hydrolyzed through trypsin and pepsin, and the antioxidant peptide HYHE is screened out; compared with chemical drugs, the antioxidant peptide HYHE serving as the biological peptide has the advantages of high stability, low immunogenicity, high purity and the like; meanwhile, the invention further proves that the dietary protein has rich nutritional value, provides a new thought for resource recycling, and has good social and economic benefits.

The invention relates to the technical field of biology, and discloses a composite nanomaterial and a preparation method and application thereof, and a composite biological nanomaterial and a preparation method and application thereof. The composite nano-material contains chitosan and nano-hydroxyapatite, the composite nano-material has a porous structure, and in the unit volume of the nano-material, the number of pores with the pore diameter of 50-100 microns accounts for 15-25%, the number of pores with the pore diameter of 50-100 microns accounts for 10-20%, and the number of pores with the pore diameter of 50-100 microns accounts for The ratio of the number of the pores with the pore diameter of 100-150 microns is 35-50%; the ratio of the number of the pores with the pore diameters of 150-200 microns is 5-18%; and the number of the pores with the pore diameter of more than 200 microns accounts for 10-23%. The composite nano material can control the release of the stem cell exosome while loading the stem cell exosome, so that the exosome quickly reaches an effective concentration, the rejection occurrence rate is reduced, and the treatment effect is improved.

The invention discloses a programmable multi-modified long-acting slow-release elastin-like protein (ELP) vector and an application thereof. A programmable biosynthesis method is utilized to construct a series of ELPs with different structures and properties consisting of different amino acids, including a composite characteristic positive charge series ELP (IVK), a composite characteristic negative charge series ELP (IVE), a composite characteristic benzene ring series ELP (IVF), a composite characteristic hydroxyl benzene ring series ELP (IVY) and a structure chimeric characteristic series ELP (IVYIVE). After subcutaneous injection, the ELP carrier is subjected to in-situ phase change under the triggering of body temperature and forms a drug reservoir, and the drug is slowly released from the reservoir to an in-vivo circulatory system, so that the effective action time of single injection of the drug is remarkably prolonged, pharmacokinetic parameters are improved, and the compliance of a patient is improved. The programmable slow-release ELP has wide application potential and is suitable for delivery of various drugs such as proteins, nucleic acids, polypeptides, antibodies and small molecule drugs.

The invention discloses an enzyme-labeled secondary antibody polymer for immunohistochemical staining. The enzyme-labeled secondary antibody polymer is formed by combining a secondary antibody and a polymer skeleton, the polymer is labeled by a labeling enzyme, the polymer skeleton is polymethylacrylic acid-2-hydroxyethyl ester, and the labeling enzyme is connected to the polymethylacrylic acid-2-hydroxyethyl ester through a coupling agent. According to the invention, polymethylacrylic acid-2-hydroxyethyl ester is used for modifying protein, so that the immunogenicity and antigenicity are reduced, the hydrolysis of protease can be weakened, and the solubility of protein molecules is improved. The enzyme-labeled secondary antibody polymer is applied to immunohistochemical staining and has high specificity and sensitivity.

The invention discloses a nano antibody for resisting vibrio parahaemolyticus and vibrio alginolyticus as well as a preparation method and application of the nano antibody. The nano antibody for resisting vibrio parahaemolyticus and vibrio alginolyticus is characterized in that a VHH sequence is formed by a framework region, a complementarity determining region and a connecting peptide for connecting the framework region and the complementarity determining region. Nucleotide for coding an amino acid sequence of the nano antibody for specifically recognizing vibrio parahaemolyticus and vibrio alginolyticus is provided, and corresponding protein or polypeptide can be obtained through expression of the provided nucleotide sequence through a proper expression system. The preparation method comprises the following steps: designing a specific primer, obtaining cDNA (complementary deoxyribonucleic acid) of a striped bamboo shark source through PCR (polymerase chain reaction), and amplifying in a library; and cloning the gene segment of the obtained PCR product to an expression vector pPICZ alpha A, transforming the plasmid to a host cell, and carrying out induced expression and transformation on the plasmid. The nano antibody obtained by the invention has strong binding capacity and specificity to vibrio parahaemolyticus and vibrio alginolyticus.

The invention belongs to the field of skin care and skin disease treatment, and provides a skin care composition and application thereof, and the skin care composition is in a liquid form and comprises recombinant collagen and glycolic acid. The specific low-concentration glycolic acid in the skin care composition disclosed by the invention ensures the mild keratin metabolism capability; the recombinant collagen with high transdermal property can quickly permeate into the deep layer of the skin, and can immediately provide a repairing raw material for the skin while the glycolic acid acts, so that discomforts such as redness and stabbing pain are remarkably relieved, and synchronous skin care and repairing is realized.

The invention relates to the technical field of biology, in particular to a mirror image coupled protein nanoparticle conjugate and application thereof. The conjugate comprises: ii) a functional protein labeled by a first peptide tag, and ii) a scaffold protein labeled by a second peptide tag, the first peptide tag and the second peptide tag being composed of D-amino acid residues; the first peptide tag and the second peptide tag form a peptide partner pair, and the first peptide tag and the second peptide tag are coupled and combined through an isopeptide bond. The conjugate provided by the invention is easier to escape from the recognition of protease, can obviously prolong the half-life period in a biological system, is not easy to cause unnecessary immunoreaction, and has good biological stability and safety.

The invention discloses recombinant hansenula polymorpha for efficiently producing cat serum albumin and an expression method of the recombinant hansenula polymorpha. According to the method, an expression cassette of the cat serum albumin is integrated in hansenula polymorpha, and a promoter in hansenula polymorpha is optimized, so that the serum albumin is expressed by a constitutive promoter and a sucrose inducible promoter independently or in a combined manner, and the copy number of the serum albumin is further optimized; the stable and efficient expression of the cat serum albumin gene in hansenula polymorpha is successfully realized. The high-density fermentation yield of the recombinant cat serum albumin fermented by using the engineering bacteria can reach 1.7-2.2 g / L.

The invention relates to a VHH combined with human CD8beta and application of the VHH. The VHH provided by the invention comprises an HCDR1 as shown in SEQ ID NO: 12, an HCDR2 as shown in SEQ ID NO: 13 and an HCDR3 as shown in SEQ ID NO: 14. The VHH provided by the invention has good binding capacity with the human CD8 beta protein and / or cells expressing the human CD8 beta protein, and provides possibility for detection, diagnosis and / or treatment based on CD8 beta.

The invention provides RNA site-directed editing by utilizing an artificially constructed RNA editing enzyme and related application. According to the present invention, an RNA recognition domain for binding RNA and a functional utility domain are fused to form a novel functional protein, and the novel functional protein specifically targets the target RNA through the recognition domain and uses the utility domain to perform RNA editing.

The invention provides a preparation method of a hydrogel mask containing silk fibroin, and relates to the technical field of cosmetics. The silk fibroin hydrogel mask comprises the following main components: silk fibroin, polyvinyl alcohol and D-sorbitol. The preparation method of the silk fibroin hydrogel mask comprises the following steps: dissolving polyvinyl alcohol at high temperature; and adding silk fibroin and D-sorbitol, uniformly mixing, injecting into a mold, carrying out circulating freezing and thawing, and obtaining the silk fibroin hydrogel mask through a physical cross-linking method. The silk fibroin hydrogel mask disclosed by the invention has the advantages of good mechanical property, good viscoelasticity and toughness, mildness, skin friendliness, high water-retaining property and remarkable moisturizing effect, and can be directly used as a mask.

The invention belongs to the technical field of cellular immune engineering, and particularly relates to a full-human-derived polypeptide for recognizing CLL-1 and application of the full-human-derived polypeptide. The polypeptide provided by the invention specifically recognizes CLL-1 and has good affinity performance, and the polypeptide specifically targeting CLL-1 provided by the invention can mark CLL-1 positive cells, can be combined with a CLL-1 antigen and the CLL-1 positive cells, and can be used as a detection reagent of CLL-1 molecules and an in-vivo tracing marking reagent. The polypeptide specifically targeting CLL-1 provided by the invention can also be used in an extracellular antigen recognition region of a chimeric antigen receptor, is used in an immune cell treatment drug targeting CLL-1, and is used for killing malignant tumors expressing CLL-1. The polypeptide for specifically recognizing the CLL-1 is a natural full-humanized antibody source, compared with a mouse antibody, a chimeric antibody and a humanized antibody, the immunogenicity of the polypeptide is greatly reduced, and the safety can be guaranteed to the maximum extent in clinical application.

The present invention discloses an osteoporosis treatment delivery system based on targeted knockdown of circBBS9 in osteoclast precursor cells. The present invention achieves the weakening of osteoclast multinucleation and bone absorption ability and retains osteoclast precursor cell related functions by inhibiting circRNA in osteoclast precursor cells using siRNA. At the same time, the above siRNA is delivered to osteoclast precursor cells in a targeted manner using cell membrane microvesicles homologous to osteoclast precursor cells, achieving the effect of treating osteoporosis, and provides a preparation method and application thereof, which solves the technical difficulty that the existing treatment methods cannot selectively inhibit specific cell stages in the osteoclast lineage.