Chemical modification of Art v 1, a major mugwort pollen allergen, by cis-aconitylation and citraconylation

Art v 1 is the major allergen of mugwort (Artemisia vulgaris) pollen, a significant cause of hay fever all over Europe. Specific immunotherapy is the only treatment modality for allergic disease. Application of modified allergens makes the treatment safer and more efficient. In this work, two out of three (ci- traconic anhydride, cis-aconitic anhydride, 2,3-dimethylmaleic anhydride) test- ed anhydrides were proven to be suitable for chemical modifications of aller- gens. Art v 1 was modified by cis-aconitylation and citraconylation in order to obtain derivatives of Art v 1 that may be suitable for further immunological test- ing. Acylation of Art v 1 gave derivatives (caaArt v 1 and citArt v 1) with about 80 % modified amino groups. The derivatives were in the monomeric form and had dramatically reduced pI values. Both derivatives were relatively stable at neutral pH values, while the acyl groups undergo hydrolysis under acidic con- ditions. Modification of allergens by cis-aconitylation and citraconylation could be a new tool for obtaining allergoids.