CORRELATION OF A MICRO-ELISA ASSAY WITH THE SKIN-TEST AND THE RAST ASSAY IN INHALANT ALLERGY

  • 1 January 1984
    • journal article
    • research article
    • Vol. 53  (2) , 143-150
Abstract
Several modifications of a previously described micro-ELISA [enzyme-linked immunosorbent assay] (IP [polystyrene surface immunosorbent and horseradish peroxidase label] Assay) for the diagnosis of [human] IgE mediated disorders were developed to increase the assay sensitivity and specificity. The absorbance values in milliunits obtained in this assay were normalized with a computer algorithm. The results of this assay correlate well with those obtained with the RAST [radioallergosorbent test] assay (normalized milliunits of absorbance vs. bound radioactivity; r = 0.74-0.87). However, the IP assay detected allergen specific IgE antibodies in many sera for which the RAST assay gave negative results (from 13.3-28% for a variety of allergens). The converse was seen in fewer than 1% of tests. In a series of 300 tests for a panel of 10 allergens, the IP assay showed a higher degree of correlation with the intradermal skin test (82%) than the RAST assay (77.3%). The specificity of the IP and RAST assays were comparable. Data showing the stability of the polystyrene surface immunosorbent and the independence of the IP assay from high levels of total IgE antibodies are presented. The reasons for higher sensitivity of the IP assay than the RAST assay (and, therefore, superior correlation with the skin test) are discussed.