request hi eff transient transfection system

[Sunil Shaw]

Oops, sorry, I omitted the message.

I'm looking for a high efficiency mammalian transient transfection 
system. to express a cell surface heterodimer.
High effiency=high percentage of positive cells (>40%) 
              High levels of expression 
              Reproducible.

I'm currently using COS-7, AprM8 vector, and DEAE-dextran/DMSO shock.
I've tried to optimize conditions re. confluency of COS cells prior to 
tx, amounts of DNA, times of incubation, DMSO shock, harvesting. 
Effeciency varies from 15-60% positive, although all the factors 
mentioned help reduce the number of poor tx.

Please send your imporvements/alternate systems/references. I will post a 
summary. 

Thanks,
Sunil
skshaw at husc.harvard.edu