To investigate the humoral immune response to common food antigens in Japanese children with IDDM.
IgG antibodies to cow's milk, β-lactoglobulin, bovine serum albumin (BSA), alpha-lactalbumin, and hen's egg ovalbumin were examined by enzyme-linked immunosorbent assay in the sera of 33 patients with IDDM, ages 11.8 ± 3.4 years. The data were compared with that of 50 normal subjects, ages 10.3 ± 5.1 years, who acted as control subjects. A positive antibody to a food antigen was defined as an antibody titer greater than the 95th percentile value in normal subjects.
Children with IDDM had significantly higher median titers of IgG antibodies to β-lactoglobulin and ovalbumin (P = 0.03 and P = 0.0005 respectively). More children with IDDM than control subjects had positive IgG antibody to ovalbumin (21 vs. 6%, P = 0.04). Titers, as well as the number of positive antibodies to other food antigens, including BSA, did not differ between the two groups.
Japanese children with IDDM show an enhanced humoral immune response to β-lactoglobulin and ovalbumin, a phenomenon that may be related to the pathogenesis of the disease.