Medical University of Lodz 1 article published in JoVE Biochemistry Visualization of Estrogen Receptors in Colons of Mice with TNBS-Induced Crohn's Disease using Immunofluorescence Damian Jacenik1, Marta Zielińska2, Sylwia Michlewska3, Jakub Fichna2, Wanda M. Krajewska1 1Department of Cytobiochemistry, Faculty of Biology and Environmental Protection, University of Lodz, 2Department of Biochemistry, Faculty of Medicine, Medical University of Lodz, 3Laboratory of Microscopic Imaging and Specialized Biological Techniques, Faculty of Biology and Environmental Protection, University of Lodz The protocol presents a complete validated TNBS-induced murine model of Crohn's disease and methods for visualization of estrogen receptors by immunohistochemistry using immunofluorescence of formalin-fixed colon sections embedded in paraffin.