Fibroblast metachromasia Cultured fibroblasts from the genetic mucopolysaccharidoses store higher than normal amounts of glycosaminoglyeans. Histochemical stains such as toluidine blue and Alcian blue can be used to detect such intracellular glycosaminoglycans which, being negatively charged, are bound and precipitated by the cationic dyes. Cultured fibroblasts from homozygotes -and heterozygotes for the genetic mucopolysaccharidoses accumulate excessive quantities of glycosaminoglycans. The cytoplasmic staining with toluidine blue is referred to as metachromasia (pink) and orthochromasia (blue) and that with Alcian blue as alcianophilia. Increased cytoplasmic staining of fibroblasts with toluidine blue. UMLS:C1835008 HP:0003610 Cellular metachromasia