Immunohistochemistry analysis of TPO on paraffin-embedded mouse kidney tissue. Antigen retrieval was performed using citrate buffer (pH6, epitope retrieval solution) for 20 mins. Sample was blocked using 10% goat serum, incubated with TPO polyclonal antibody (Product# PA5-80125) with a dilution of 1 µg/mL (overnight at 4°C), and followed by biotinylated goat anti-rabbit IgG (30 minutes at 37°C). Development was performed using Streptavidin-Biotin-Complex (SABC) with DAB chromogen method.