Can backround in IHC be caused by poor fixation or any other part of the
tissue processing? I'm using an ABC kit to stain mouse brain tissue. When
I omit primary antibody, my section is completely blank. I've tried three
different rabbit polyclonal antibodies and I've blocked with peroxide,
goat and rabbit serum. In every case the backround is unchanged. When I
decrease primary concentration, the backround and signal decreases.

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   \    Peter Poon                           \     _         ______ |
    \   http://cafe.berkeley.edu/~peterp      \  /   \___-=0`/|0`/__|
     \  (510)649-9654                          \_\          / | /    )
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