immunofluorescence - (Jul/03/2006 )

I am trying to stain some liver cell source human protein. I use HepG 2 as pos. control and c2c12 as the neg. control. But I got strong signal at c2c12 and almost no signal at HepG2. Does some one can tell me what's going on?

is it reproducible? are you sure of your antibodies?