The ASL-32 mAb reacts with an antigen epitope shared by CD66a, c and e. CD66a/c/e are members of the CEA (carcinoembryonic antigen) family of the Ig superfamily. CD66 plays a role in hemophilic and heterophilic adhesion. CD66a, also known as CEACAM1 and BGP (biliary glycoprotein), is mainly expressed on granulocytes, binds to CD66a, c, e, and CD62E. CD66c (known as CEACAM6, NCA) is expressed on granulocytes and epithelial cells. The ligands of CD66c are CD66a-e, CD62E and Galectins. CD66e molecule is also called as CEA or CEACAM5, primarily found on epithelial cells. CD66e binds to CD66a, c and e.