Evaluation of RAST inhibition as a method for the standardization of house-dust extracts

Abstract

RAST-inhibition was evaluated as a method for the in vitro standardization of house dust allergens, using four lyophilized house-dust preparations of different degree of purification (R1, R2, R3 and R4). When a serum pool of highly house-dust sensitive patients was used, a qualitatively similar potency sequence by RAST-inhibition between the different preparations could be established as with in vivo skin testing. When, however, individual sera were examined, striking differences were observed in both the qualitative and the quantitative potency relationships. Furthermore, large variations were noted in duplicate measurements in RAST-inhibition.

From this study it became clear that in vitro RAST inhibition and in vivo skin tests can have only statistical meaning for the standardization of house-dust allergen. In individual patients, striking differences may occur in the response to different preparations, thereby making standardization by these techniques rather unsatisfactory. By applying these techniques, we gained the impression that patients were being characterized rather than allergens.