Measurement and clinical importance of antibodies to glycosphingolipids.

Measurement of antibodies against gangliosides and other glycosphingolipids (GSLs) is technically demanding because of their low affinity for antigen. A recent workshop, in which twelve laboratories received a coded panel of sera containing anti-GM1 antibodies, demonstrated that the immunoassays varied widely in sensitivity and in criteria employed for a positive test. The fine specificity of anti-GSL antibodies should be characterized by analyzing their reactivity with a panel of GSLs with related structures. High-titer monoclonal IgM antibodies against gangliosides and sulfated carbohydrates appear to cause neuropathy in some patients. Low-titer polyclonal antibodies against gangliosides occur frequently in a variety of diseases, including autoimmune diseases without neurological symptoms. It is unclear whether these polyclonal antibodies are a primary manifestation or a consequence of the disease, and their clinical importance is uncertain at present.