Human Serum IgE against Two Major Allergens from Cow Hair and Dander: Determination of Affinity and Quantity of Antigen‐Specific IgE

The quantity and quality of antigen-specific IgE against purified major allergens from cow hair and dander was measured by a double-antibody radioimmunoassay. In serum from patients with allergic asthma to cow the affinity constant varied from 1 to 150 × 109 1/mol and the number of antibody combining sites from 0.01 to 0.4 × 10−9 mol/1 serum for each antigen.