Description
This antibody recognizes a cell surface glycoprotein of 80-95kDa, called CD44, or HCAM, on lymphocytes, monocytes, and granulocytes (Leucocyte Typing Workshop V). Its epitope is resistant to digestion by trypsin and chymotrypsin. The CD44 family of glycoproteins exists in a number of variant isoforms, the most common being the standard 85-95kDa or hematopoietic variant (CD44-s). Higher molecular weight isoforms are described in epithelial cells (CD44-v), which are believed to function in intercellular adhesion and stromal binding. HCAM antibody immunostaining is commonly used for the discrimination of urothelial transitional cell carcinoma in-situ from non-neoplastic changes in the urothelium