Spectrin is a cytoskeletal protein that lines the intracellular side of the plasma membrane of many cell types in pentagonal or hexagonal arrangements, forming a scaffolding and playing an important role in maintenance of plasma membrane integrity and cytoskeletal structure. In certain types of brain injury such as diffuse axonal injury, spectrin is irreversibly cleaved by the proteolytic enzyme calpain, destroying the cytosketelon. Spectrin cleavage causes the membrane to form blebs and ultimately to be degraded, usually leading to cell death. Primary antibodies are available purified, or with a selection of fluorescent CF® Dyes and other labels. CF® Dyes offer exceptional brightness and photostability. Note: Conjugates of blue fluorescent dyes like CF®405S and CF®405M are not recommended for detecting low abundance targets, because blue dyes have lower fluorescence and can give higher non-specific background than other dye colors.