I am trying to test out this new pig siRNA in PK-15 cells, but have yet to be successful. I have tried using Lipofectamine 300 and multiple different nucleofection codes that I could find in publications or on the Lonza website. My lab has a Lonza 4D nucleofector, just for reference. My transfection efficiency has been no more than 50% and quite often much lower. To actually be able to see knock-down, I need a much higher efficiency. Any suggestions would be greatly appreciated!