The pharmaceutical industry is experimenting with using biological matter as therapeutic agents. The size of these biological substances is usually very large, and thus, they find it difficult to permeate easily through cell membranes. The two main methods used for transfection are introduction of foreign DNA and RNA. However, toxicity of transfection reagents causes cell mortality. There is a need to develop safer and more efficient methods of transfection to study compound activity and for basic genetic research that depends on expression of transgenes and transfection.
Let us have a look at some techniques used for transfection:
Lipsosome-mediated transfection: Liposomes are similar in chemical composition to the phospholiped bilayer in cell membranes. They are capable of encapsulating nucleic acid in the presence of RNA or DNA, and thus, act as delivery systems.
Non-liposomal transfection: Certain non-liposomal lipids can form complexes with DNA or RNA to give rise to micelles. This technique is useful in places where liposomal transfection doesn't work.
Dendrimer-based transfection: Dendrimers are macromolecules that can condense DNA in complexes, and thus, achieve high efficiency in certain tissue culture models.
Electroporation: This technique is normally used to deliver nucleic acid to cells grown in-vitro in suspension. Electricity is used to create pores in the membrane and RNA/DNA is delivered to targeted cells.
Microinjection: Microinjections or gene guns are used when the cells to be targeted are present inside a larger population. Thus, methods directly delivers the DNA into chosen cells.
Virus mediated gene delivery: Viruses can be used as carriers to introduce DNA into mammalian cells. This is also called viral transduction. This method is useful for in vivo gene delivery and primary cell culture transfection. However, it carries significant risk in laboratory use.
The ideal transfection method should give good transfection yield and decrease the mortality of cells. Non toxic transfection is the need of the hour.
Natalie Halimi, Project manager at inter dev - internet marketing company