Masson’s trichrome staining is used to discriminate collagen fibers from muscular tissues on histological slides. This staining is a mix of 3 stains:
– A purple nuclear stain (hematoxylin)
– A red cytoplasmic stain (a mix of xylidin ponceau and acid fuchsin)
– A collagen fiber stain: light green or anilin blue
The discrimination between collagen fibers and the other components of tissue matrices is linked to a difference in permeability. Indeed, the red acidic cytoplasmic stain labels the tissue acidophilic components like collagen fibers. When treated with the Phosphotungstic Acid, the less permeable components retain the red stain, while the red diffuses from the loose texture fibers of collagen and at the same time is replaced by the light green dye.
Masson’s trichrome staining is widely used to study muscular pathologies (muscular dystrophy), cardiac pathologies (infarct), hepatic pathologies (cirrhosis) or kidney pathologies (glomerular fibrosis). It can also be used to detect and analyze routinely tumors on hepatic and kidney biopsies.
Masson’s trichrome staining can be applied in all types of organs and tissues, except from brain and spinal cord.