Immunohistochemistry (Paraffin) analysis of Topoisomerase I in paraffin-embedded human small intestine tissue using TOP1 Monoclonal Antibody (Product # MA5-38375) diluted at 1:100. After dewaxing and hydration, antigen retrieval was mediated by high pressure in a citrate buffer (pH 6.0). Section was blocked with 10% normal goat serum 30min at RT. Then primary antibody (1% BSA) was incubated at 4°C overnight. The primary is detected by a Goat anti-rabbit IgG polymer labeled by HRP and visualized using 0.05% DAB.