242 results about "Chinese hamster" patented technology

The invention provides CD2V protein of African swine fever (ASF) capable of being expressed with high-efficiency in a CHO (Chinese hamster ovary) cell strain. The amino acid sequence of the CD2V protein is shown in SEQ ID NO:4; a recombinant plasmid constructed by the invention is used for expressing the CD2V protein of an African swine fever virus in CHO cells; the invention further provides a recombinant CHO cell strain prepared by transfecting the CHO cells through the recombinant plasmid, the recombinant CHO cell strain can be used to prepare the CD2V protein, and the prepared protein canbe used for differential diagnosis of the African swine fever. According to the cell strain with the expression of the CD2V protein of the African swine fever, the expression quantity is high, purification is easy, the cell strain can be used for the differential diagnosis, and a solid foundation is laid for the production of subunit vaccines and diagnostic reagents of the African swine fever.

The invention discloses a taming method of non-serum culture medium for mammal cell, which contains cross tumour cell, Chinese hamster oophoron cell (CHO) and 293-cell.

The present invention relates to a cell-based method for producing influenza virus vaccines by enriching the population of surface-bound α2,6-sialic acid receptors on a cell surface, such as on a Chinese Hamster Ovary (CHO) cell surface. The host cell therefore presents numerous binding sites to which an influenza virus can bind via its hemagglutinin spike protein and infect the host cell. In contrast to wild-type CHO cells, the surface of the mutated CHO cells of the present invention contains an enriched population of α2,6-sialic acid receptors which makes the inventive CHO cells highly susceptible to viral infection, and therefore safe, effective, and highly efficient cells for rapidly producing influenza vaccines.

The invention discloses a serum free medium for expressing erythropoietin in CHO (Chinese hamster ovary) cells, and a culture method for high expression of erythropoietin in CHO cells. The serum free medium contains additives D-glucose and sodium butyrate, and also contains one or more of D-galactose, D-mannitose and N-acetylglucosamine. The culture method comprises the steps of: performing serumculture on activated seed cells by using a serum medium, and then performing serum free culture by the serum free medium. By adopting the medium and culture method disclosed by the invention, recombinant human erythropoietin protein of high and stable expression can be obtained, and the glycosylation degree of erythropoietin is improved, i.e. the specific gravity of EPO (erythropoietin) sialic acid is improved. As high as 1.0*107IU recombinant human erythropoietin can be obtained from one liter of culture fluid by the culture method provided by the invention, the expression is stable, and theculture method is simple and suitable for large-scale production.

The intervention relates to a CHO (Chinese Hamster Ovary) cell strain of an efficiently-expressed recombinant human nerve growth factor and a construction method thereof and belongs to the field of biotechnology. The preservation number of the cell strain is CGMCC No. 4541, and the recombinant human nerve growth factor (rhNGF) with biological activity can be stably expressed. The invention also discloses a method for constructing the CHO cell strain; and through cell transfection, gene amplification and subcloning screening carried out on an amplified cell line, an efficiently-expressed monoclonal cell strain suitable for serum-free suspension culture is obtained. The invention simultaneously discloses a recombinant human nerve growth factor sequence secretly expressed by the CHO cell strain; and the secrete recombinant human nerve growth factor has good biological activity, so that PC12 multiplication can be kept outside a human body, PC12 cell differentiation is induced, and the chick embryo dorsal root ganglion nerve fiber growth is stimulated to lay a good foundation for the large-scale industrialization preparation of the recombinant human nerve growth factor.

The invention discloses a recombinant human-like collagen protein-human original cell growth factor fusion protein and a preparation method and application thereof. The prepared fusion protein is provided with a special fibrous structure and good biological tissue compatibility, and can promote proliferation and differentiation of epidermis cells, endothelial cells and fibroblast cells. The preparation method comprises the following steps: obtaining encoded DNA sequence of the fusion protein, reconstructing and recombining fusion protein expressed by an expression vectors in escherichia coli, pichia pastoris or chinese hamster ovary cells. The fusion protein comprises a first zone and a second zone, wherein the first zone has at least 85% of sequence homology with human collagen protein and has the function of the human collagen protein, and the second zone has at least 85% of human original cell growth factor and has the function of the human original cell growth factor; connecting peptide is arranged between the first zone and the second zone; the general formula of the connecting peptide is (GGGS)n; preferably, the amino acid sequence of the fusion protein is SEQ ID NO. 15.

The invention relates to a multi-arm polyamino acid (ester) grafted polyethyleneimine copolymer, a preparation method and application in gene delivery. The method includes the steps of: dissolving polyamine initiator in organic solvent and initiating the ring opening polymerization of alpha-amino acid-N-carboxylic acid anhydride protected by phenmethyl under anhydrous and oxygen free conditions to obtain the multi-arm polyamino acid (ester); and then causing the full or partial aminolysis reaction to occur between benzyl ester at the lateral chain of the multi-arm polyamino acid (ester) and amino group of polyethyleneimine to form the grafted copolymer. The polymer is a novel high-efficiency polycation gene vector, integrates the properties of polyethyleneimine and polyamino acid and is high in transfection efficiency, and the highest transfection efficiency to the mediate luciferase plasmid of Chinese Hamster Ovary epithelial cell is ten times than that of the Lipofectamine2000 of the commercial transfection reagent in US Invitrogen biomax under the same conditions; cytotoxicity is small; and cell survival rate is over 80% within the best transfection rate range, thus having broad application prospect.

The invention discloses a CHO (Chinese hamster ovary) cell serum-free medium. The culture medium comprises main components such as amino acids, inorganic salt components, vitamins, trace elements, yeast hydrolysates, albumin and the like. The CHO cell serum-free medium disclosed by the invention does not contain any serum components and animal-derived components, and is increased in affinity compared with that of other serum-free mediums. Cells can be directly inoculated into the serum-free medium from a serum culture medium or other serum-free mediums and grow normally, thus eliminating a cumbersome domestication process. By adopting the CHO cell serum-free medium, the growth density and the viability of CHO cells are improved, the tolerance of the cells therein is increased, the growth platform maintenance time is prolonged, most importantly, the ability of CHO engineering cells to express foreign proteins in the CHO cell serum-free medium is improved, and the product yield is greatly enhanced.

The invention relates to an efficient eukaryotic expression vector capable of effectively expressing an antibody and other target proteins and a preparation method and an application thereof, belonging to the technical field of biotechnology. The vector is formed by inserting a nuclear matrix adhering zone, a marmot hepatitis virus post-transcriptional control sequence, a ribosome entry site sequence, a dhfr1-105aa gene segment or a dhfr106-187aa gene segment on a pCI-neo plasmid. According to the invention, the defects that time and energy are wasted when the traditional mammalian cells are expressed and screened and target protein expression level is low are overcome, and a vector transfection CHO (Chinese Hamster Ovary) cell applying the vector can obtain a monoclonal cell strain capable of stably and efficiently expressing antibodies or fusion proteins in a short time, thus the vector provided by the invention has good application value for efficient expression and industrialization of recombinant protein.

The present invention relates to humanized bispecific anti-HER2 antibodies that comprise one antigen binding site containing variable regions of heavy and light chain of trastuzumab, and another antigen binding site containing variable regions of heavy and light chain of pertuzumab. The bispecific anti-HER2 antibodies is effective for treating cancer, such as breast cancer, gastric cancer, or ovarian cancer. Preferred bispecific anti-HER antibodies of the present invention are afucosylated antibodies. The present invention also relates to Chinese Hamster ovary (CHO) mutant cell line that has a dysfunctional Slc35C1 gene, which is the only dysfunctional gene in the mutant that affects glycan regulation.

It is intended to provide an overexpression vector which makes it possible to easily acquire a high-level producing strain with the use of mammalian cells, in particular, Chinese hamster ovary cells (CHO cells) as a host. Namely, an expression vector capable of inducing high productivity of a genetically modified protein in animal host cells which comprises a promoter strongly inducing expression, a multicloning site for gene integration and a polyadenylation signal sequence, in this order starting from the upstream, and a drug-resistance gene having no promoter functioning in animal cells in the downstream thereof.

The invention relates to a kit for detecting deoxyribose nucleic acid (DNA) residues of a Chinese hamster ovary (CHO) cell and a using method thereof. The kit comprises DNA extracting solution, polymerase chain reaction (PCR) amplification reaction liquid, a DNA quantitative reference product of a CHO cell genome, a negative quality control product, a positive quality control product and DNA diluent. In the kit, EvaGreen is used as a fluorescent dye, and the DNA of the CHO cell genome is detected by a real-time quantitative PCR technology; and products such as a treatment protein medicament, a recombinant vaccine, a monoclonal antibody and the like from the CHO cell can be accurately and quantitatively detected.

Provided herein are methods and compositions for producing Factor VIII proteins. Such methods include introducing into a cell a nucleic acid molecule encoding a Factor VIII protein operably linked to a promoter, wherein the promoter is characterized by the ability to produce commercially viable Factor VIII protein; and incubating the cell under conditions for producing commercially viable Factor VIII protein. Also provided are nucleic acid molecules which encode a Factor VIII protein operably linked to a Chinese hamster elongation factor 1-α (CHEF1) promoter, which may be used in the methods provided herein.

The invention discloses a Chinese hamster ovary culture medium as well as a preparation method and application thereof. The culture medium comprises ascorbic acid, pyridoxine hydrochloride, vitamin B12, nicotinamide, riboflavin, thiamine chloride, choline chloride, folic acid, calcium pantothenate, sodium pyruvate, reduced glutathione, inositol, biotin, hypoxanthine, putrescine, lipoic acid, linoleic acid, thymine, glucose, HEPES (2-hydroxyethyl) buffer solution, dextran sulphate, Pluronic-F68, various amino acids and salts thereof and various inorganic salts. The culture medium has low cost, and the component does not contain animal origin ingredients, does not contain protein and has definite chemical ingredients. All ingredients are cooperated and blended, and the Chinese hamster ovary culture medium can satisfy the basic growth requirement of cells, and can effectively regulate, transfer and control the culture of cells so as to realize good high-density cell culture. Compared with the culture effect of the existing culture medium, the culture effect of culture medium disclosed in the invention is at least equivalent to even superior to the existing culture medium.

The invention relates to preparation of a cell culture medium, and particularly provides preparation of a novel serum-free protein-free defined-chemical-component cell culture medium. The culture medium contains multiple amino acids, vitamins, inorganic salts, minor elements, carbohydrates and other supplementary factors. The culture medium is free of any extract or hydrolysate. The culture medium is free of any animal-derived component. The culture medium can well support in-vitro suspension culture of CHO (Chinese hamster ovary) cells, and satisfies the demands for CHO cell culture. The culture medium contains defined chemical components, and is low in cost.

The invention relates to a codon optimized fatty acid desaturase (FatI for short) gene sequence and application thereof. A eukaryotic expression vector is constructed, and is transfected in Chinese hamster ovary (CHO), and a cell strain which stably expresses FatI is obtained through G418 screening; through genome polymerase chain reaction (PCR) and Southern Blot determination, an exogenous gene is integrated into a genome, and the exogenous gene can be transcribed into mRNA in the cell; a n-3/n-6 value of a cell of the successfully transfected CHO cell line is improved by 8.47 percent than that of a control cell; and therefore, the FatI gene sequence can promote n-6 fatty acid in the cell to be converted into n-3 fatty acid.

The present invention generally relates to processes and compositions for the transfection of Chinese hamster ovary (CHO) cells. More specifically, the present invention relates to processes for the transfection of CHO cells suspended in an aqueous medium using a transfection composition containing nucleic acid and linear polyethyleneimine.