A stable lyophilized reagent for use in a potential reference assay for quantitation of anti-D in immunoglobulin products

Quality control of anti-D immunoglobulins intended for in vivo clinical use requires in vitro assay of potency, A lyophilized biotinylated monoclonal anti-D (biotinylated Brad-5; 99/698) has been evaluated for its suitability to serve as a working reagent in a competitive enzyme-linked immunoassay (EIA) for anti-D quantitation. The reagent demonstrated acceptable stability in accelerated degradation tests and following reconstitution. Twelve international laboratories obtained comparable potencies for each of nine anti-D samples using 99/698 in a standardized assay procedure using erythrocytes fixed to microtitre plates. We also describe the use of trehalose for stabilization of dried erythrocyte-coated microtitre plates. (C) 2002 The International Association for Biologicals. Published by Elsevier Science Ltd. All rights reserved.