77 results about "Cricetulus" patented technology

The invention discloses a Chinese hamster ovary (CHO) genetic engineering cell line for performing high-level secretory expression on AcAPc2 and relates to a CHO cell line for performing high-level secretory expression on the AcAPc2. The invention aims to solve the problems that the expression level of an exogenous gene product expressed by using CHO is low at present and the industrialized production cannot be realized. The CHO genetic engineering cell line for performing high-level secretory expression on the AcAPc2 is obtained by the following step of: screening dihydrofolate reductase-deficient CHO cells which are taken as host cells, and amplifying to obtain the cell line for performing stable and high-level expression on the AcAPc2. The CHO cell line can perform high-level expression on the AcAPc2; the expression level can be up to 10mg / L.72h; and the CHO cell line can be industrially produced. The cell line is used for resisting blood coagulation and treating tumor, septicaemiaand the like.

Processes vectors and engineered cell lines for large-scale transfection and protein production in mammalian cells, especially Chinese Hamster Ovary (CHO) cells are described in which transfection efficiencies are realized through the use of a single vector system, the use of functional oriP sequences in all plasmids, the use of codon-optimized Epstein-Barr virus nuclear antigen-1 (EBNA1) constructs the use of a fusion protein between a truncated Epstein-Barr virus nuclear antigenen-1c (EBNA1c) protein and a herpes simplex virus protein VP16, the use of a 40 kDa fully deacetylated poly(ethylenimine) as a transfection reagent, the use of co-expression of a fibroblast growth factor (FGF) and / or the use of protein kinase B to potentiate heterologous gene expression enhancement by valproic acid (VPA).

The invention discloses a gene sequence for expressing soluble recombinant human hyaluronidase PH20 by a CHO (Chinese hamster ovary) cell. The gene sequence has a nucleotide sequence shown in SEQ ID NO.2; after a kozak consensus sequence is added to 5' terminal of the optimized gene sequence, the optimized gene sequence is connected to pOptiVEC-TOPO carrier, and stably transferred to the Chinese hamster ovary cell improved by genetic engineering, so as to achieve high expression of the soluble recombinant human hyaluronidase PH20 in a mammalian cell.

The invention relates to a selection method of a signal peptide while foreign protein is expressed by Chinese hamster ovary cells and an application thereof, which belong to the technical field of biology. An information analysis technology is adopted; 29 kinds of high-secretory expression signal peptides and foreign protein tandem sequences commonly used in CHO cells are analyzed; finally, 10 signal peptides with proper analysis results are selected, 10 different secretory signal peptides are connected with the 5'end of the tandem epitope gene through a PCR method, eukaryotic expression vectors are constructed respectively, mammalian cell CHO is transfected, Western blot is adopted to detect the cumulative difference of recombinant epitope proteins in a CHO culture medium, and the resultproves that the cumulative difference of the proteins conforms to the selection result of the method, so that the feasibility of the method is proved.

The invention discloses a recombinant long-acting human hyaluronidase. The recombinant long-acting human hyaluronidase is a fusion protein PH20-HSA or PH20-IgFc of a human hyaluronidase PH20 extracellular part and a human protein (albumin HSA fragment or immunoglobulin IgG2Fc fragment), and the amino acid sequences of the PH20-HSA and the PH20-IgFc are represented by SEQ ID No. 4 and SEQ ID No. 5 respectively, and have the advantages of high in-vivo safety and long half-life. The invention also discloses an encoding gene, an expression vector, a host cell, a production method and a stable preparation of the recombinant long-acting human hyaluronidase. The achievement of industrial level and the obtaining of purified products with active energy are realized through expressing by using GC-rich high expression system and through producing Chinese hamster cells (CHO). The invention further discloses an application of the recombinant long-acting human hyaluronidase in cooperative dosage and the production of micro-molecular hyaluronic acid.

The present invention relates to the identification of a genomic integration site for heterologous polynucleotides in Chinese Hamster Ovary (CHO) cells resulting in high RNA and / or protein production.More specifically it relates to CHO cells comprising at least one heterologous polynucleotide stably integrated into the S100A gene cluster of the CHO genome and to methods for the production of saidCHO cells. Further, the invention relates to a method for the production of a protein of interest using said CHO cell and to the use of said CHO cell for producing a protein of interest at high yield. Integration within these specific target regions leads to reliable, stable and high yielding production of an RNA and / or protein of interest, encoded by the heterologous polynucleotide.

A process for the purification of recombinant human Chorionic Gonadotropin (hCG) from a sample of crude recombinant hCG in the supernatant of CHO cells comprises the combined use of ion-exchange chromatography and reverse phase HPLC. The ion-exchange chromatography is performed twice and the final use of a size exclusion chromatography allows the purification from any residual traces of contaminants. The specific bioactivity of the highly purified hCG obtained from the process is particularly high, amounting to about 25.000 IU / mg.

A new method for selecting clones and recloning mammalian cells which are of importance for the production of biopharmaceuticals, preferably hamster or mouse myeloma cells, with a high degree of automation and throughput. The invention relates to methods of depositing and replicating single cell clones of the cells in question. The invention also relates to methods of preparing proteins using cells which have been obtained and replicated by single cell deposition as well as compositions which allow the replication of single cells.

The present invention relates to an improved method for cell line development which is generally applicable to production of any therapeutic protein that can be produced using mammalian Cell lines and in particular Chinese Hamster Ovary (CHO) cells. The method combines site directed integration (SDI), expression construct components improving the post-transcriptional processing of the gene of interest (GOI), novel design of the GO genome target location and the introduction of a onetime pre-CLD host cell line selection workflow to generate a production competent cell line that can then be used in multiple CLD efforts from that point on.

A horseshoe crab Factor C protein having activity of Factor C, wherein the horseshoe crab is selected from Tachypleus tridentatus, Limulus polyphemus, and Carcinoscorpius rotundicauda, and wherein the horseshoe crab Factor C protein is produced through being recombinantly expressed from a Chinese Hamster Ovary (CHO) DG44 cell or HEK cell.

The invention provides a cell model stably expressing a human-derived CaSR gene. The cell model is preserved in China Center for Type Culture Collection and named as Chinese hamster ovary cell CHO-CaSR, with a preservation number being CCTCC NO: C201893. A construction method of the cell model is as follows: a SNAP tag and a CaSR gene are linked by a linking sequence cacgcgt to obtain the CaSR gene fused with the SNAP tag, the CaSR gene is linked with an expression vector to construct a recombinant plasmid containing the CaSR gene, the recombinant plasmid is transfected into mammalian cells, and a cell strain capable of stably expressing the CaSR gene is cultured by drug screening. The cell model can be used for screening CaSR-targeted active substances, and can also be used in conjunctionwith homogeneous time resolved fluorescence (HTRF) through SNAP-tag to accurately and quickly study interaction of CaSR with other proteins and oligomerization of the CaSR. The cell model can screenhigh-throughput and low-cost active substances targeting the CaSR, and the screening method is simple and controllable in steps, low in cost, high in throughput, and very good in stability and reliability.

The invention discloses a cell strain for producing a biosimilar drug of Ustekinumab and a production method thereof. The Chinese hamster ovary cell S cell strain is preserved in the China Center for Type Culture Collection (CCTCC), and the preservation number is CCTCC NO: C2020232. The cell strain expresses a fully human monoclonal antibody resisting a p40 sub-unit shared by human IL-12 and human IL-23. The fully humanized monoclonal antibody for resisting the p40 sub-unit shared by the human IL-12 and the human IL-23 is a biosimilar drug of Ustekinumab, not only shows high consistency with the Ustekinumab in pre-clinical research, but also passes pharmacokinetic bio-equivalence and safety similarity evaluation in clinical research, and the provided biosimilar drug of Ustekinumab is the first one that enter the clinical test period in China, is the only one that completes the I stage clinical test, and is one of the biosimilar drugs of Ustekinumab, which are the fastest in application in the international.

Type-C endogenous retroviruses (ERVs) embedded in Chinese hamster ovary (CHO) cells were altered to modify the release of retroviral and / or retroviral-like particles in the culture supernatant. Although evidence for the infectivity of these particles is missing, their presence has raised safety concerns. 173 type-C ERV sequences that clustered into functionally conserved groups were identified. Transcripts from one type-C ERV group were identified to be full-length with intact open reading frames, and to have corresponding viral RNA genomes that were loaded into retroviral-like particles. Also, sequence analysis of the genomic RNA from viral particles indicated that they may result from few expressed ERV sequences. Disclosed herein is the disruption / alteration of the gag gene of the expressed ERV group using CRISPR-Cas9 genome editing. Comparison of CRISPR-derived mutations at the DNA and mRNA level led to the identification of a single ERV locus responsible for the release of viral RNA-loaded particles from CHO cells. Clones bearing a Gag loss-of-function mutation in this particular ERV locus showed a reduction of viral RNA-containing particles in the cell supernatant by over 250-fold. Notably, ERV mutagenesis did not compromise cell growth, cell size or recombinant protein production. Provided herein is a new strategy and cells, in particular engineered CHO cells, to mitigate potential contaminations from CHO endogenous retroviruses during biopharmaceutical manufacturing.

The invention belongs to the technical field of cell recombination and protein expression, particularly relates to a CHO cell line for stably expressing African swine fever CD2v protein as well as a construction method and application of the CHO cell line, and discloses the CHO cell line for stably expressing the African swine fever CD2v protein, which is a Chinese hamster ovary cell CHO-CD2v. The strain is sent to Guangdong Microbial Culture Collection Center for preservation on November 11, 2021, and the preservation number is GDMCC No: 62052. According to the cell line, an exogenous gene CD2v is integrated into a known safe site in a Chinese hamster genome, so that normal expression of a transferred gene is realized without influencing normal physiological functions of cells, and the cell line is simple in construction process and high in cloning accuracy. The cell line can be used in the aspects of high-yield CD2v protein, drug effect screening of African swine fever, vaccine production and the like, and has very important significance in diagnosis of African swine fever and vaccine production.

This invention relates to site-specific integration and expression of recombinant proteins in eukaryotic cells. In particular, the invention includes compositions and methods for improved expression of antibodies including bispecifc antibodies in eukaryotic cells, particularly Chinese hamster (Cricetulus griseus) cell lines, by employing an expression-enhancing locus.