In situ hybridization - molecular biology (May/24/2002 )

After in vivo transfection, I have to demonstrate that my construction is kept by cells after 1 month. How could I perform this ?
We have already demonstated that cells expressed the protein of interest, but we would like to demonstrate that after a long time, transduced cells conserved the plasmid. What kind of method should we used to perform this?
Thanks

If your construct is highly expressed you can try FISH. If you want to answer the question directly in situ PCR is the answer