Artifacts in Mast Cell Metachromasia Produced by Hyaluronidase Preparations.

Abstract
Pretreatment of sections of hamster tissues with aqueous or heat inactivated aqueous testicular hyaluronidase solutions abolished all metachromatic (toluidine blue) staining of mast cells at pH2 and 3. Pretreatment with 0.12 [image] sodium chloride solution of hyaluronidase resulted in normal staining at the above pH''s. Evidence suggests that commercially available hyaluronidase preparations con-tain substances, perhaps proteins, which form a complex with mast cell mucopolysaccharides and prevent staining at low pH values.