Just recently I used a piece of small intestine as a control for an antibody.
The staining intensity was nice and dark.  Now I am doing a patient run with the
same antibody, same conditions, same everything and the positive control has a
much decreadsed intensity .  I tried cutting a new section and staining it the
very next day and still not as intense.  The antibody in question was Cox-2 and
the tissue was small intestine.  I am pretty sure that this marker is used to
look at inflammation(as well as other things I am sure) and I was wondering if
perhaps we have already cut through the part of the tissue with inflammation.
Has anyone ever heard of such a thing?

Thanks in advance,
Christine