Application of WGA lectin staining for visualization of the connective tissue in skeletal muscle, bone, and ligament/tendon studies

During immunostaining of specific proteins in tissue sections using monoclonal and polyclonal antibodies, visualization of general tissue staining/background or major structural features is helpful to pinpoint precise localization of the protein of interest. Often in skeletal muscle research, immunostaining with antibodies against connective tissue or plasma membrane proteins (collagen 1, laminin, and caveolin 3) are used for this purpose. Although immunostaining for these proteins works well, it is time consuming, costly, limits the number of antibodies against protein of interest that can be used on a single section, and is not applicable to some staining techniques. Lectins were frequently used in earlier publications for skeletal muscle fiber boundaries and connective tissue visualization, but are not common in the current research studies. This work investigates costaining of muscle, bone, ligament, and tendon tissue sections with fluorescently tagged wheat germ agglutinin (WGA) lectin as a tool for the visualization of connective tissue. The results of this study show that fluorescent WGA lectin costaining is a cost-effective, fast, and convenient method for connective tissue visualization, especially in the studies where extensive washes reduce staining of the structures that are the primary interest of the investigation.