Pemphigus is one of such autoantibody-mediated disorders, which is caused by pathogenic autoantibodies against epidermal desmosomal cadherins, desmoglein (Dsg) 1 and Dsg3. Because these autoantibodies can directly disrupt epidermal cell-cell adhesion,1 their concentration in the epidermis would be linked to the disease severity. ...we irradiated mouse ears with ultraviolet B and demonstrated a positive correlation of IgG1-MFI with the ultraviolet B irradiation dose (r = 1.00) (Fig 2, C) and with the intensity of skin inflammation as evaluated by ear swelling (r = 0.90) (Fig 2, D). ...to confirm that local inflammation predisposes to the development of the pemphigus phenotype, we used a pathogenic antimouse Dsg3 antibody, AK23. In summary, our results in mice suggest that local inflammation might also enhance anti-Dsg3 antibody deposition in the skin in patients with pemphigus. ...taking skin biopsies from perilesional erythematous (presumably inflammable) areas in autoimmune blistering diseases might be beneficial to increase the DIF sensitivity. NS indicates not significant. 1 M. Amagai, S. Karpati, R. Prussick, V. Klaus-Kovtun, J.R. Stanley, Autoantibodies against the amino-terminal cadherin-like binding domain of pemphigus vulgaris antigen are pathogenic, J Clin Invest, Vol. 90, 1992, 919-926 2 Y. Kano, M. Shimosegawa, Y. Mizukawa, T. Shiohara, Pemphigus foliaceus induced by exposure to sunlight: report of a case and analysis of photochallenge-induced lesions, Dermatology, Vol. 201, 2000, 132-138 3 D.R. Mehregan, R.K. Roenigk, L.E. Gibson, Postsurgical pemphigus, Arch Dermatol, Vol. 128, 1992, 414-415 4 G. Egawa, S. Nakamizo, Y. Natsuaki, H. Doi, Y. Miyachi, K. Kabashima, Intravital analysis of vascular permeability...