Chapter 6 – Western Blot

Western blotting (WB) is a most common technique used to detect specific proteins in biological samples. It utilizes simple principles to separate proteins according to their size and to bind them to a support allowing their detection with a specific antibody. WB is a powerful technique to detect a single or a complex of proteins and to monitor changes in expression or posttranslational modifications. Many variations of this assay exist that can be summarized in several simple successive steps that makes Western blotting relatively easy to perform and troubleshoot. In this chapter, we will (1) explain the principles underlying the Western blot assay; (2) describe a basic protocol that can be adapted to specific requirements; (3) provide examples of its use in biomedical research and diagnostic; and (4) emphasize its key limitations. It should equip the reader with the necessary knowledge to perform and interpret Western blot assays.