cos7 cells

[Mr. G. Morley]

 Hello all, a colleague of mine is having difficukty culturing some
COS7     cells. The cells are not prolliferating well in media and I was
wondering if anyone had any ideas or encountered the same problem.
It is unlikely that  the foetal calf serum is  at fault as the problem has manifested 
itself quite recently and  the fcs batch has not chabged.
I would be obligued at any ideas,
thanks in advance.....
gary morley