If the section was a paraffin section, and the original antibody didn't work - in other words the section is essentially unstained - then you should be able to stain it with another antibody using standard peroxidase-DAB. If there is any peroxidase-DAB pigment in the tissue from the original staining attempt, you won't be able to remove it, and will have to work around it, either by ignoring it if it is sufficiently light, or by using a different substrate this time, that will produce a different color. If the section was a frozen section, then dehydrating it after the original stain prior to coverslipping may have denatured the antigen to the point where it will no longer be recognized by the antibody. In that case you could try antigen retrievel, but I don't know how well that would work.
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