I have been trying to transfect my Huh 7 cells, but each time after 48 hours from transfection in the centre of well i see small rounded cells they not even floating but i think they dead. I can only see gfp on the outskirts of well where the cells are not tiny. I tried PEI, lipofectamine and jet prime, they still die, i always do transfections around 3pm- 4pm and change media the next morning. I use antibiotic containing media, but with lipofectamine i use antibiotic free media. Only once did i find that my cells never died so i continued to do immunofluoresnce staining but i couldnt pick up any signal from antibodies, the GFP control wells showed that transfection did work, i did the same procedure with hek 293 cells and i could pick up antibody signal so the problem is not the antibodies any suggestion on why my cells are dying?