An enzyme immunoassay for the determination of low levels of IgA in human serum

Abstract An enzyme immunoassay (EIA) has been developed which facilitates the detection of low levels of immunoglobulin A in human serum. IgA is captured by an anti-IgA antibody linked to micron-sized polyacrylamide beads and subsequently detected by an anti-IgA horseradish peroxidase conjugate. The standard curve is linear in the region between 25–1000 ng/ml IgA. The assay is particularly suited to measure IgA antibodies in sera from IgA-deficient individuals and IgA contaminants in blood products.