As Paul suggested, my first thought is that the background is due to the
use of mouse monoclonals. A mouse-on-mouse kit may help, but my limited
experience with these has not been very positive; they may be a bit
unpredictable, and/or cause a marked decrease in the signal. Much
preferable is to use primary antibodies from another species.
Jean-Martin Lapointe, DMV, MS, dACVP
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