Hello,

 I'm using a CD3 marker grown in mice that cross reacts with rat.  However
I'm getting a lot of background staining in

 axillary tissue on the slides.(mainly heart.) Doe anyone have any
suggestions to eliminate this backround staining.  I'm using

a Vector Elite Peroxidase kit and my CD3 marker is made by PharMingen. I'm
staining rat tissue. and I have already tried Casein(Sigma),

Power Block(BioGenex), an anti-mouse IgG rat adsorbed biotinylated antibody
as the secondary antibody.   All help is much appreciated.



                                   Jim Zimmerman
                       james.zimmerman@pharma.novartis.com