Establishment of CHO cell line stably expressing insulin like growth factor-1

Objective To establish CHO cell lines stably expressing human insulin like growth factor-1(IGF-1).Methods Plasmid vector pSec-IGF-1 that contains a cDNA fragment coding for human IGF-1 was transfected into Chinese hamster ovary(CHO) cells by a lipofectin-based method,and transfected CHO cells were selected in culture medium containing hygromycin B.Condition medium of positive cell clones was collected,and measured by Western blot and ELISA.The positive cell clones were also analyzed by immunohistochemistry.Results Eight CHO cell clones expressed 7.7kDa IGF-1 protein analyzed by Western blot,2 of which ecpressed IGF-1 at the level more than 2mg/L. Conclusion We established CHO cell lines stably expressing human IGF-1.