Ventana Medical Systems, Inc. Congo Red Staining Kit 860-026

Congo Red Staining Kit is used to selectively demonstrate Amyloid in tissue sections. The staining reaction is based on the application of congo red which stains the patterns of atypical proteins (amyloid). The b-pleated sheets of amyloid are suitable in size and shape to accommodate the congo red molecules, which are held in the lattice work of the b-pleated sheets. Birefringence is an intrinsic property of the amyloid fibril congo red complex. Congo red may also stain unexpected structures such as: keratin, elastic and dense collagen fibers. Without both the red staining of congo red and the apple green birefrengence under polarization a definite identification cannot be made. The hematoxylin is applied as a contrasting blue nuclear stain. The Congo Red Staining Kit stains amyloid a bright pink to red and nuclei blue. Amyloid may appear as circular or ribbon-like pink staining deposits throughout the tissue. It has a particular predilection for deposition in blood vessel walls and basement membranes. Nuclear staining may vary from light to dark blue depending on the tissue section and thickness (6-10 microns).