“Cytoplasmic” Islet Cell Antibodies: Evidence That the Target Antigen Is a Sialoglycoconjugate

We have biochemically treated (periodate, borohydride, neuraminidase, organic solvents) frozen sections of human pancreas and studied the reactivity of islet-cellantibody-positive human sera and monoclonal antibodies. The autoantigen of pancreatic sections has the properties ofsialic acid containing glycolipid.