eosophageal cells

[John Fox]

In article <3jpitv$mb0 at ash.shu.ac.uk>, J.R.Fox at shu.ac.uk (John Fox) says:
>
>In article <alan.1.001DE799 at gecko.biol.wits.ac.za>, alan at gecko.biol.wits.ac.za (Alan Thornley) says:
>>
>>We are trying to transfect a line of eosophageal carcinoma keratinocytes with 
>>an inducible expression vector (pMSG-Cat). At present we are having a lot of 
>>trouble with maintenance of the plasmid in the cells. Does anybody have any 
>>ideas???
>
>Could you specify the problems that you are encountering please?

I have had a think about your problem and conferred with a colleague.
We have come up with the following ideas in response to your question:

1) Is the insert too large for the cells to be able to "cope" with?

2) You should investigate the toxicity of the proteins produced.

3) Is your selection procedure ( eg. Ab resistance) effective for your system?

4) You might consider the harshness of the transfection procedure that you 
employ. Are you cells dying a few days after transfection due to this harsh 
procedure?