1. Perform the A-B blocking step prior to the primary antibody. If a protein block is used before the primary, add the A-B block prior to the protein-blocking step.
2. Incubate tissue sections with Avidin Block for 10-15 minutes.
3. Wash two times with buffer.
4. Incubate tissue sections with Biotin Block for 10-15 minutes.
5. Wash two times with buffer.
6. Apply primary antibody to the tissue section.
Wood GS and Warnke R. (1981). J Histochem Cytochem. 10,1196-204.