Nonchemically Mediated Methods
The age-old transfection pitfalls remain. Cells die after they are transfected, or cells remain healthy only because they are not transfected.
“Increasing the transfection efficiency will simplify and clarify experimental answers. For example, if you have a population of cells that are only 50% affected, it can be difficult to determine the true response to treatment,” said Steve Kulisch, cell biology business unit manager at Bio-Rad.
“Transfection efficiency rates with many immortalized cell lines are quite good. However, researchers continue to adopt additional, more challenging cell lines in their work, forcing the scientific-tools community to keep up.”
The desire to get more efficient delivery of biomolecules forces innovation. With the vast number of cells researchers use today, the Holy Grail is to find some technology or technique that is efficacious for all cell lines with minimal amounts of optimization.
Cellular variations include: varying lipid compositions in the plasma membranes and different cell sizes with ranging amounts of exposed surface areas. Adherent versus suspension cultures affect surface area as well. Getting the material into the cell is step one. Step two is getting that biomolecule imported to where it needs to be; some cells are more efficient at biomolecule transport than others.
Bio-Rad pioneered electroporation as a transfection methodology and also offers biolistic devices. These devices coat small gold or tungsten microparticles with nucleic acids or proteins, then use a helium blast to accelerate the microparticles into the sample.
Although the company’s technologies have not changed dramatically since their introduction, a recently introduced electroporation buffer assists with opening up the pores on the cells and also provides energy to help with recovery, improving electroporation transfection efficiency.
Many basic research questions are still first addressed by transfecting easy-to-access and easy-to-culture, but also artificially immortalized or cancer-derived, cell lines. To confirm that insights gained from these “artificial” cell line systems reflect the in vivo situation, there is a need to switch to more biologically relevant models.
For therapeutic approaches, the use of primary animal cells could reduce the number of animal tests, and use of primary human cells allows extrapolating findings from such animal models.