Eureka! Institutional Repository

Background: High concentrations of antibodies against food derived antigens have been correlated with the development of several diseases; in particular, high concentrations of antibodies against Neu5Gc, a sialic acid present in products of animal origin that can be synthesized by them but not by humans, have been detected in various autoimmune diseases such as Hashimoto’s thyroiditis, diabetes and several types of cancer. After entering the body, Neu5Gc is embedded in human proteins, provoking, however, immune response. The capability of such antibodies to bind specific human proteins with structural homology with the food derived antigens may be involved in the development of the diseases. The proteins that have been linked with Alzheimer’s disease, β-amiloyd peptide and tau protein, undergo glycosylation, therefore, they could be modified embedding Neu5Gc. In the present study, antibodies against Neu5Gc were measured in the cerebrospinal fluid of 12 healthy individuals and in patients with mild (12), moderate (9) and severe (5) Alzheimer’s disease. Methods: For the detection of antibodies against Neu5Gc, the antigens were attached at the bottom of ELISA plates. Results: No distinction was observed between the concentrations of anti-Neu5Gc IgG, IgM and IgA antibodies on healthy individuals and patients with Alzheimer’s disease. Thus, the food derived antigen Neu5Gc does not appear to have any involvement in the pathophysiology of the disease