EVALUATION OF ALLERGENIC POTENCY BY REAST INHIBITION - A NEW TOOL FORTHE STANDARDIZATION OF ALLERGENIC EXTRACTS

The potency of allergenic extracts can be determined in vitro by RAST inhibition, and this has become the preferred method for the standardi zation of allergens. A disadvantage of this technique is the impossibi lity of obtaining data about allergens bound to the solid phase, i.e., the counterpart of the inhibiting extract. The REAST (reverse enzyme allergosorbent test) is based on the capture of IgE by a specific anti body bound to microtiter wells, the reaction of captured IgE with biot inylated allergen and the development of a colour reaction by subseque nt addition of streptavidin-peroxidase and chromogenic substrate. The addition of an allergen extract in a dose-response fashion competes wi th the biotinylated allergen and inhibits the test. In the present stu dy REAST inhibition has been evaluated with Dermatophagoides pteronyss inus, Parietaria judaica and mixed grass pollen extracts. The correlat ion of REAST inhibition with RAST inhibition and both intra-assay and inter-assay reproducibility have been evaluated. REAST inhibition is a potentially valuable new tool for the standardization of allergenic e xtracts.