Immunohistochemistry analysis of Mucin 1/MUC-1 showing staining in the cytoplasm and membrane of paraffin-embedded human breast carcinoma tissue (right) compared to a negative control without primary antibody (left). To expose target proteins, antigen retrieval was performed using 10mM sodium citrate (pH 6.0), microwaved for 8-15 min. Following antigen retrieval, tissues were blocked in 3% H2O2-methanol for 15 min at room temperature, washed with ddH2O and PBS, and then probed with a Mucin 1/MUC-1 Rabbit Polyclonal Antibody (Product # PA5-16847) diluted in 3% BSA-PBS at a dilution of 1:100 for 1 hour at 37°C in a humidified chamber. Tissues were washed extensively in PBST and detection was performed using an HRP-conjugated secondary antibody followed by colorimetric detection using a DAB kit. Tissues were counterstained with hematoxylin and dehydrated with ethanol and xylene to prep for mounting.