Searching for a CAT antibody !

[milstone]

As of several years ago, the only available anti-CAT antibodies were 
problematic, at best. Positive staining required very high levels of CAT 
protein, especially compared to the low levels detectable by the 
enzymatic assay for CAT. There was, and may still be, a commercial 
source for these Abs. My impression is that, unless you are absolutely 
committed to visualizing CAT as a reporter gene product (e.g., you must 
analyze irreplaceable samples from previous experiments performed with 
CAT), that you will be much better off switching to another reporter, 
such as luciferase (Abs are available) or beta-galactosidase (Abs are 
available & histocheimstry is easy), which is more easily localized. 
This is true even if you must repeat a some experiments.

--Dave