[Histonet] Strange CD3 staining on K9 / Fel Intestine

[Melanie Walker]

Hello Histonet, 

 

One of the pathologists here recently pointed out some strange staining
occurring on both K9 and Fel tissue using the CD3 stain. There appeared
to be very strong staining of the intestinal epithelium, all along the
villi. The staining was comparable in strength to that of the positive T
cells, does not appear as simple "fringe effect". We are using lymph
node for the K9 control and Spleen for the Fel - both controls stained
appropriately/ normally. I recently switched to a new lot of antibody -
could this have such a strange effect? We are using  rabbit polyclonal
CD3 from Biocare and it has been working great for the past year or so. 

 

Has anyone ever encountered epithelial staining with a CD3 marker?

 

In addition, I there appeared to be some non-specific nuclear staining
with the CD79 marker on these same cases... I don't think this relates
but is also a new problem for us (though I hear has been an ongoing
problem for some). 

 

Melanie Walker