Adaptation of enzyme-linked immunosorbent assay to the avian system

Abstract

A microplate enzyme-linked immunosorbent assay was developed to detect chicken anti-reovirus antibodies. Studies of the parameters which affect the outcome of the assay with avian serum revealed 2 aspects for a successful assay. First, enzyme-antibody conjugates prepared by the periodate oxidation technique retained far more immunological activity than conjugates produced by a glutaraldehyde cross-linking. Second, the results indicated an unusually high affinity of chicken Ig for the microplate plastic which was mostly eliminated by a pretreatment technique with fixed fetal calf serum. The enzyme-linked immunosorbent assay compared favorably with the latex passive agglutination test, yielding a titration endpoint of 1:51,000, or approximately 1300 times more sensitive than the latex passive agglutination assay. The assay was sensitive to less than 1 ng of specific antibody and had low to moderate variance and high reliability.