Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P00492 (hypoxanthine-guanine phosphoribosyltransferase)
 2,385 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have previously developed an accumulative site-specific gene integration system (AGIS) using Cre-recombinase and mutated loxP sites. AGIS enables repeated transgene integration into a predetermined chromosomal site in mammalian cells. However, the process of establishing cells with multiple integrated copies of the transgene is still time-consuming. In the present study, we describe an improved version of AGIS that facilitates and accelerates the establishment of high-producer Chinese hamster ovary (CHO) cells. Two donor vectors were simultaneously introduced into the cells in a single transfection. Cells with successfully targeted transgene integration were screened based on a change in the color of the reporter fluorescent protein that they express. Repeated rounds of integration allowed the transgene copy number to be increased. As a model, an scFv-Fc antibody gene was integrated into the hprt locus of the CHO cell genome. After three rounds of integration, a high-producer CHO cell clone with six copies of the scFv-Fc gene was successfully established. scFv-Fc productivity was approximately four-fold greater than a control cell line harboring a single copy of the transgene. This newly designed AGIS procedure should facilitate the development of producer cells suitable for biopharmaceutical protein production.
 ...
PMID:Accumulative scFv-Fc antibody gene integration into the hprt chromosomal locus of Chinese hamster ovary cells. 2866 17

Chinese hamster ovary (CHO) cells have been used as host cells for the production of pharmaceutical proteins. For the high and stable production of target proteins, the transgene should be integrated into a suitable genomic locus of host cells. Here, we generated knock-in CHO cells, in which transgene cassettes without a vector backbone sequence were integrated into the hprt locus of the CHO genome using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 and CRISPR-mediated precise integration into target chromosome (CRIS-PITCh) systems. We investigated the efficiency of targeted knock-in of transgenes using these systems. As a practical example, we generated knock-in CHO cells producing an scFv-Fc antibody using the CRIS-PITCh system mediated by microhomology sequences for targeting. We found that the CRIS-PITCh system can facilitate targeted knock-in for CHO cell engineering.
 ...
PMID:Targeted knock-in of an scFv-Fc antibody gene into the hprt locus of Chinese hamster ovary cells using CRISPR/Cas9 and CRIS-PITCh systems. 2929 84