Techniques used for lung transfection:

In order to enable gene transfer into mammalian somatic cells while they are still alive, a variety of different techniques of gene delivery have been devised. Rats’ lungs were effectively and selectively transfected when two recombinant plasmids, either alone or in association with cationic liposomes, were injected into their trachea. These plasmids included the bacterial gene chloramphenicol acetyltransferase, which is activated by utilizing the early promoter or enhancer of the cytomegalovirus. When the promoter/enhancer for simian virus 40 was used, there was absolutely no transfection that could be detected. When it comes to the process of transfecting the lungs, the effectiveness of insufflating plasmid DNA was on par with that of plasmid-liposome complexes. After inhaling plasmid DNA alone or plasmid-liposome complexes, the CAT gene was expressed in the lungs as soon as one day later, and it persisted for more than 21 days beyond that point. The insufflation of either kind of plasmid led to the expression of the gene. 

In contrast, there was no indication of transfection of the lungs following intravenous injection of either plasmid alone or complexes of plasmid and liposomes. This was the case regardless of whether the complexes included plasmid alone or liposomes alone. Intra-tracheal injection of DNA from recombinant plasmids may be significant for lung-specific gene therapy owing to the fact that it is simple to use and does not produce any of the potential side effects that are associated with other methods of gene delivery. 

The transient expression of therapeutic genes inside lung allografts has the potential to control pathogenic processes that occur after allotransplantation. Although there is evidence that viral vectors can carry genes to the lungs effectively, the use of such vectors is restricted due to concerns about their safety.