Three transfection reagents, Lipofectamine® 2000, TransIT-PRO® and linear 25 kDa polyethylenimine were evaluated for transient expression of enhanced green fluorescent protein in Chinese hamster ovary ce...Three transfection reagents, Lipofectamine® 2000, TransIT-PRO® and linear 25 kDa polyethylenimine were evaluated for transient expression of enhanced green fluorescent protein in Chinese hamster ovary cells. TransIT-PRO® was found to be more efficient under the examined conditions, but comes at an increased cost compared to the widely used PEI.展开更多
An expressive plasmid pSMTPCH was constructed from porcine growth hormone gene,sheep metallothionein promoter (MT-011)and the vector,pUC19. The linear pSMTPGH and circular pSV2-dhfr were cotransfected into CHO-dhfr ce...An expressive plasmid pSMTPCH was constructed from porcine growth hormone gene,sheep metallothionein promoter (MT-011)and the vector,pUC19. The linear pSMTPGH and circular pSV2-dhfr were cotransfected into CHO-dhfr cell by calcium phosphate coprecipitation. Positive clones made up 74% of total clones, which were identified with ELISA. The expression of pSMTPGH was induced by 0.5 μM of Cd ̄++. The clone 1-C-3 was found to secrete hGH at the level of 3800 μg/10 ̄6 cells/24 hrs in media containing 10 μMTX. After 20 generations in culture, the clone was still stable with hGH expression.The molecular weight of secreted protein was the same as that of the natural pGH, 22KD;the identity was further supported by Western blot.展开更多
文摘Three transfection reagents, Lipofectamine® 2000, TransIT-PRO® and linear 25 kDa polyethylenimine were evaluated for transient expression of enhanced green fluorescent protein in Chinese hamster ovary cells. TransIT-PRO® was found to be more efficient under the examined conditions, but comes at an increased cost compared to the widely used PEI.
文摘An expressive plasmid pSMTPCH was constructed from porcine growth hormone gene,sheep metallothionein promoter (MT-011)and the vector,pUC19. The linear pSMTPGH and circular pSV2-dhfr were cotransfected into CHO-dhfr cell by calcium phosphate coprecipitation. Positive clones made up 74% of total clones, which were identified with ELISA. The expression of pSMTPGH was induced by 0.5 μM of Cd ̄++. The clone 1-C-3 was found to secrete hGH at the level of 3800 μg/10 ̄6 cells/24 hrs in media containing 10 μMTX. After 20 generations in culture, the clone was still stable with hGH expression.The molecular weight of secreted protein was the same as that of the natural pGH, 22KD;the identity was further supported by Western blot.