Glycolipids as the Major Autoantigens of Cytoplasmatic Islet Cell Antibodies

Abstract

It has been recently suggested that pancreatic glycolipidic extracts and acidic glycolipid fractions are able to block the binding of ICA to frozen sections of human pancreas. We study the prevalence of blocking effect by the upper-phase from human pancreatic glycolipid extracts (PGE) in thirty-eight sera ICA positive from seventeen IDDM patients and twenty-one first relatives of type 1 diabetics. Total inhibition was found in 82% and 76% insulin dependent diabetes mellitus patients and first relatives of type 1 diabetics respectively. Partial and no inhibition of ICA + sera was seen in 6%, 12% of type 1 diabetics and 19%, 5% of the first degree relatives of type 1 diabetics respectively. Our study suggests that there is heterogeneity of cytoplasmatic islet cell antibodies and that glycolipids are the major autoantigen of ICA.

Key Words:

• Islet cell antibodies
• Gangliosides
• Glycolipids
• Insulin-Dependent Diabetes
• Autoantigen