(A) ELISA for Relative Potency: An ELISA competition assay has been developed for the standardization of allergenic extracts. Current potency testing of most allergenic products is performed using the RAST inhibition assay. A 10 week validation study was completed which consisted of performing 64 tests on each of 10 products (8 grass pollens and 2 mites). Dr. Rastogi reviewed the data from the validation study and calculated the acceptability criteria for the ELISA. With the implementation of this assay, we will reduce the expense and the personnel time incurred by this laboratory in the testing of allergenic products prior to their release for sale. Currently, studies are proceeding to test giant ragweed and American, German, and Oriental cockroaches using the ELISA competition assay. (B) Chemiluminescence for Immunoblots: A chemiluminescent method of performing immunoblots has been developed for the standardization of allergenic extracts. The current immunoblot technique for allergenic products is performed using Blotted RadioIsotopic IsoElectric Focusing (BRIEF). Successful implementation of the chemiluminescent methods (Blotted IsoElectric Focusing - Light or BIEF-LIGHT), would greatly reduce the expense and personnel time incurred by this laboratory in the testing of allergenic products in support of PLA's and for use as a new reference, and for semi-annual testing of all references for stability. Initial studies with several grass pollens and short ragweed pollen have shown the BIEF-LIGHT to be more sensitive, safer (no radioisotope), and faster. A Validation study of the BIEF-LIGHT method is currently in process that included testing all of the CBER allergenic references by both the BIEF- LIGHT and the BRIEF methods. (C) Improved Ninhydrin test for total protein.
