ORF expression in Mammalian cells is very useful for many applications: protein production with HEK293, over-expression of tagged protein for immuno-tracking or immuno-precipitation, development of a cell line for drug discovery such as a cancer model expressing PD-1 or PD-L1…

Unfortunately, plasmid delivery into primary cells and cell lines is often challenging, providing low or even no transfection efficiency. The solution is a robust lentiviral system.

So, how do you identify the right lentiviral system? With the titer! The higher is the better. 10⁷TU/ml is ok… and 10⁸TU/ml is very good.