Do the group II dust mite allergens correspond to lysozyme?

Much effort has been devoted to the characterization of the allergens of house dust mites, such as Dermatophagoides pteronyssinus and D. farinae, since they are associated with atopic asthma. Such studies have culminated in the immunochemical, biochemical, and molecular characterization of several allergens, in particular allergens designated groups I, II, III and IV. The allergen groups I, III, and IV have been demonstrated to be a cysteine protease, trypsin, and amylase, respectively, suggesting that some of the more important mite allergens play a role in mite-digestive processes. Despite these gains, the identity of the major allergens designated group II remains unknown, notwithstanding the fact that they have been cloned and that their amino acid sequences have been determined. Data from our laboratory would now suggest that the group II allergens correspond to lysozyme, an enzyme associated either with defense against bacteria or in food digestion. (DBO)