Funding sources This work was supported by a grant from the Ministry of Health, Labour and Welfare (Research for Intractable Diseases), and from the Ministry of Education, Culture, Sports, Science and Technology.
CLINICAL AND LABORATORY INVESTIGATIONS
Detection of antibodies against the non-calcium-dependent epitopes of desmoglein 3 in pemphigus vulgaris and their pathogenic significance
Article first published online: 11 JUN 2012
© 2012 The Authors. BJD © 2012 British Association of Dermatologists
British Journal of Dermatology
Volume 167, Issue 2, pages 252–261, August 2012
How to Cite
Kamiya, K., Aoyama, Y., Shirafuji, Y., Hamada, T., Morizane, S., Fujii, K., Hisata, K. and Iwatsuki, K. (2012), Detection of antibodies against the non-calcium-dependent epitopes of desmoglein 3 in pemphigus vulgaris and their pathogenic significance. British Journal of Dermatology, 167: 252–261. doi: 10.1111/j.1365-2133.2012.10929.x
Conflicts of interest None declared.
- Issue published online: 26 JUL 2012
- Article first published online: 11 JUN 2012
- Accepted manuscript online: 8 MAR 2012 02:41PM EST
- Accepted for publication 27 February 2012
Background Antidesmoglein (anti-Dsg) 3 serum antibody titres are usually correlated with the disease activity of pemphigus vulgaris (PV), but some patients retain high titres even in remission.
Objectives The aim of our study was to determine whether anti-Dsg3 antibodies in PV sera recognized calcium (Ca2+)-dependent or non-Ca2+-dependent epitopes, and to evaluate their pathogenicity.
Methods Dsg3 baculoprotein-coated enzyme-linked immunosorbent assay (ELISA) plates were treated with 0·5 mmol L−1 ethylenediaminetetraacetic acid (EDTA). The binding ability of anti-Dsg3 monoclonal antibodies (mAbs) was analysed. Eight of the 83 patients with PV who were screened had elevated Dsg3 ELISA index values > 100 in remission. The binding ability of these PV sera was analysed. We evaluated the pathogenicity of anti-Dsg3 serum antibodies against the non-Ca2+-dependent epitopes using a dissociation assay.
Results The reactivity of pathogenic anti-Dsg3 mAbs against the Ca2+-dependent epitopes diminished markedly in the EDTA-treated ELISA, whereas no such reduction was observed in mAbs against the non-Ca2+-dependent epitopes. The sera of all the patients contained antibodies against both Ca2+-dependent and non-Ca2+-dependent epitopes. In six out of the eight patients, the ratio of antibodies against Ca2+-dependent to non-Ca2+-dependent epitopes decreased in remission. EDTA-treated Dsg3 baculoproteins adsorbed anti-Dsg3 serum antibodies against the non-Ca2+-dependent epitopes, but the remnant PV antibodies retained the ability to induce acantholysis in the dissociation assay.
Conclusions We have established an assay to measure indirectly the titres of anti-Dsg3 serum antibodies against the Ca2+-dependent epitopes, based on the differences between EDTA-untreated and EDTA-treated ELISA index values, as a routine laboratory test to reflect the pathogenic anti-Dsg3 serum antibody titres more accurately.