Which test detects antibodies to specific allergens using a radioimmunoassay technique?

Which test detects antibodies to specific allergens using a radioimmunoassay technique?

• A. RAST
• B. ELISA
• C. Western blot
• D. Immunofluorescence

Answer: (A)

Detecting specific IgE antibodies to particular allergens with a radioactivity-based readout is the idea behind this assay. In this test, the allergen is bound to a solid support, patient serum is added so that any IgE antibodies specific to that allergen attach, and then a radiolabeled anti-IgE antibody is introduced to bind the IgE. The measured radioactivity reflects how much allergen-specific IgE is present in the serum. This is the classic radioimmunoassay approach for allergy testing, historically known as RAST. Other methods use different labels or detection principles. An enzyme-based assay (ELISA) relies on a color change to quantify antibodies, while Western blot and immunofluorescence use protein separation or fluorescence, respectively, rather than a radioactive signal.

Detecting specific IgE antibodies to particular allergens with a radioactivity-based readout is the idea behind this assay. In this test, the allergen is bound to a solid support, patient serum is added so that any IgE antibodies specific to that allergen attach, and then a radiolabeled anti-IgE antibody is introduced to bind the IgE. The measured radioactivity reflects how much allergen-specific IgE is present in the serum. This is the classic radioimmunoassay approach for allergy testing, historically known as RAST.

Other methods use different labels or detection principles. An enzyme-based assay (ELISA) relies on a color change to quantify antibodies, while Western blot and immunofluorescence use protein separation or fluorescence, respectively, rather than a radioactive signal.