[Histonet] It's a mystery . . .

[Jackie M O'Connor]

Hi Histonetskis - 
Maybe I'm thinking too hard - I can't seem to get rid of false positive 
staining in negative control sections of human and mouse kidney human and 
pancreas tumor.  I'm using EDTA HIER (for the first time), in an SABC 
protocol with a Goat Pab.  I've tried two different (vendor) Rab anti Goat 
biotinylated secondarys.   I'm using an avidin/biotin block - each for 20 
minutes, (two different lots/vendors) but I'm still getting this false 
staining in the negative (omitted primary) control sections.  Is it 
possible to not be able to block ALL biotin? I've never seen this before. 
I can't imagine what else I'm seeing - but like I said - my brain is 
tired.  Before I switch to an HRP conjugated secondary - can anyone 
suggest what else this could be?  I know EDTA can cause background, but 
there is no primary on these sections.  Will someone loan me their brain?  
I can't help but wonder if the EDTA is causing my mystery - but I have to 
use it. 
Help me, Obi-wan-kenobi.

Jackie O'