Specificity: Recognizes the human CD44 cell surface antigen, a 100kD glycoprotein widely expressed on human leucocytes, white matter of the brain and by some epithelial cells of the intestine and of the breast. CD44 expression may be up-regulated upon some carcinomas, and it has been speculated that this may be related to metastatic potential. This product is routinely tested in flow cytometry on human peripheral blood lymphocytes