Radioallergosorbent Test (RAST)

A radio immunoassay designed to detect allergens responsible for tissue hypersensitivity. The protein allergen is bound to a surface such as plastic plates or spheres. The patient’s serum is added. If the serum contains antibody to the allergen, the antibodies will attach to the allergen. The level of attachment is measured and the amount quantified. The test may be designed the other way where the lgE antibodies are placed on the surface. Then an extract of the product, such as a glove, is added to the test to determine if allergens are present.