Are they compatible? I have a MSCV expression construct (I received from someone) but other packaging constructs needed for making infectious particles are not of MSCV, but of MMLV origin (gag-pol and VSV-G plasmids). Will I get any infectious MSCVs if I transfect these plasmids in 293 cells?
Hi Vibhu, I have used the pmx onco-retrovirus which is based on the MSCV backbone, You can certainly use VSVG (I did). Indeed you can use a number of different Env genes as required to direct the specificity of your infection (VSVG is fairly pan-trophic and will pretty much infect most things I think but it tends to be a bit more toxic to cells because of that).
I am uncertain of the gag-pol. My instinct says they should work but I think you may just have to try it.
Sorry I can't be more help!
Gary
Hey Gary, Thank you for taking time and sharing your experience. I actually tried the combination once and it didn't work out ( I did not get any GFP expression in MSCV infected cells). Thinking that I either need to try and concentrate the viral supernatant by PEG precipitation (in case the yield was very low) or PCR out my construct from the MSCV vector and clone it in to MLV backbone now.
Hi Vibhu - if you are having problems then you might be right to PCR and re-clone. I remember to get high virus titres I used to "Ping-Pong" the virus back and forth in HEK293 cells. I did have a problem initially getting virus but I traced this to the "FBS" replacement I was using (I was trying to use a defined animal free FBS replacement and for some reason this killed the virus's ability to transfect). Sorry I can't be more help and good luck with your transfections in the future!
Gary
- Badges
- Science method