Submitted to: Cytotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/28/2006
Publication Date: 11/17/2006
Citation: Ogay, I.D., Lihoradova, O.A., Azimova, S.S., Abdukarimov, A.A., Slack, J.M., Lynn, D.E. 2006. Transfection of insect cell lines using polyethylenimine. Cytotechnology 51(2):89-98.
Interpretive Summary: Insect cell cultures have become important tools in the production of biological substances for use in a variety of research, human and veterinary medicine, and pest control applications. These applications often require the introduction of foreign DNA (transfection) into the cells and have generally used methods originally developed for use with human and other mammalian cell cultures. While these methods can be successfully employed, they are often less efficient with insect cells and frequently involve complex procedures or require specialized equipment. Even when they do work, they may require substantial modification because of differences in the culture medium or growth patterns of insect cells. In the past few years, a new transfection substance, polyethylenimine, has been found very useful with hard-to-transfect cells. Because of its low toxicity, the techniques for its use are typically less complex than other methods. In the current study, we have utilized this reagent with insect cells – using a fall armyworm cell line to adapt the procedures to insect cells and then testing it with seven other lines. These results will be of interest to researchers in government, academic, and commercial labs that work with molecular techniques, especially those already using insect cells in these studies.
Technical Abstract: Insect cell lines have been widely used in recombinant baculovirus expression systems and transient gene expression studies. Critical to these applications have been the transfection of foreign DNA. This has been widely done using labor intensive and cytotoxic liposome-based transfection reagents. In the current study we have optimized a new kind of polyethylenimine-based DNA transfection reagent on the Spodoptera frugiperda Sf9 insect cell line. A plasmid vector that transiently expresses green fluorescent protein (GFP) was effectively delivered into Sf9 cells. A transfection efficiency of 54% and cell viability of 85-90% were obtained for Sf9 cells. The developed transfection protocol has now been successfully used to transfect eight insect cell lines derived from Bombyx mori, Trichoplusia ni, Helicoverpa zea, Heliothis virescens and S. frugiperda with GFP and GUS with transfection efficiencies of at least 45%. This method provides high heterologous protein expression levels, transfection efficacy and cell viability, and could be used for transient gene expression in other lepidopteran cell lines.