Try heating the samples - for whole-mount mouse embryos I've done 20
minutes at 70C - works like a charm! I think you could probably go 10-15
min for sections - the 20 min is probably overkill. I did the heat
inactivation in Tris buffered saline + Tween (TBST), but I've seen
protocols where the heating was done in PBS.

I don't have an original reference on this - if anyone does, I'd love to
have it!

Tamara

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 Tamara Howard
 Department of Cell Biology and Physiology
 University of New Mexico - Health Sciences Center
 Albuquerque, NM 87131
 thoward@unm.edu
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