Transfection of mammalian cells by the methods of receptor mediated gene transfer and particle bombardment

The efficacy of currently developed methods for gene transfer into mammalia n cells depends primarily on the transfection technique, and also on the ty pe of targeted cells. Considering the importance of gene transfer in the cr eation of gene therapies, our study was aimed at the assessment of transfec tion capacity of receptor mediated gene transfer method (RMGT), and method of particle bombardment (helios gene gun system - HGG) in different normal and malignant mammalian cells ex vivo. In addition, the HGG was also assess ed for its ability to transfect tumor cells of subcutaneous (s.c.) tumors i n C57B1/6 mice in vivo. Using RMGT an average ex vivo transfection rate of 35.7%; and 20.4% was achieved in malignant melanoma B-16, and human breast adenocarcinoma MCF7, respectively. However, in normal fibroblast L929 cells the transfection by RMGT succeeded only in 2.1% of the cells. On the other hand, the transfection efficacy of HGG was comparable in both malignant ce ll lines resulting in an average gene transfer to 9.6% of B-16 and 10.5% of MCF7 cells, while only 3.9% of normal fibroblasts were successfully transf ected. Application of HGG for an in vivo gene transfer into s.c, B-16 melan oma tumors in C57B1/6 mice resulted in a successful but limited transfectio n of the epithelium as well as of the superficially sited tumor cells. Taki ng into consideration both methods, RMGT is more appropriate for ex vivo tr ansfection of cells, under the condition that target cells express a specif ic receptor for the molecule attached to the carrier. On the other hand, HG G is not complicated to use, no requirements for specific structures on tar get cells are necessary (potentially usable in different cells), and it has applicability in direct in vivo transfection processes.