I need some help with an autofluorescence problem.  I'm using immersion
fixed FFPE rat cardiac tissue and have been trying a Texas Red
conjugated secondary antibody.  When I look at the tissues using either
a Texas Red or a WG filter cube, the red blood cells light up like
christmas.  I'm using a connexin antibody, so the RBCs should not be
positive.  The fluorescence doesn't appear to be due to antibody
nonspecificity as I've seen this in unstained tissues as well.  I've
tried to quench the autofluorescence with NaBH4 (0.1% in PBS), but to no
avail.  I'm not sure what else to try and am ready to switch to another
fluor, but would really like to know what is going on here.  Has anyone
else had similar problems.  Is there a way to correct this, or is Texas
Red just not compatable with bloody tissues?


Thanks,

Brandon Schanbacher
--
Division of Pharmacology
Ohio State University