Diacron-reactive oxygen metabolites levels are initially elevated in bullous pemphigoid patients

Reactive oxygen species (ROS) are involved in the pathogenesis of bullous pemphigoid (BP), but this involvement has not been fully elucidated. In this study, to further elucidate the pathogenic role of ROS in BP, we examined the results of the diacron-reactive oxygen metabolite (d-ROMs) test and the biological antioxidant potential test for 16 BP patients who visited our hospital before being treated with systemic corticosteroids. In the BP patients, the average d-ROMs levels, expressed in Carratelli units (U.CARR), were significantly reduced at 1 month of treatment (from 335.6 ± 40.3 U.CARR to 224.7 ± 61.6 U.CARR, P<0.001). Bullous Pemphigoid Disease Area Index (erosions/blisters) scores correlated with d-ROMs levels (r=0.51), suggesting that those levels reflect the disease severity. We also performed staining of 3,5-dibromotyrosine (DiBrY) in skin tissues. DiBrY is expected to be a marker of tissue damage related to inflammation and allergies. The DiBrY was stained in infiltrated cells around the dermis, throughout the blister fluid, and at the basement membrane within the blister. It is considered that tissue destruction caused by the myeloperoxidase released from neutrophils and by eosinophil peroxidase released from eosinophils is involved in blister formation. The results suggest that ROS play a role in BP.