Autoantibodies against the epidermal desmosomal cadherins desmoglein 1 (Dsg1) and Dsg3 have been shown to cause severe to lethal skin blistering clinically defined as pemphigus foliaceus (PF) and pemphigus vulgaris (PV). It is unknown whether antibody-induced dissociation of keratinocytes is caused by direct inhibition of Dsg1 transinteraction or by secondary cellular responses. Here we show in an in vitro system that IgGs purified from PF patient sera caused cellular dissociation of cultured human keratinocytes as well as significant release of Dsg1-coated microbeads attached to Dsg-containing sites on the keratinocyte cellular surface. However, cell dissociation and bead release induced by PF-IgGs was not caused by direct steric hindrance of Dsg1 transinteraction, as demonstrated by single molecule atomic force measurements and by laser trapping of surface-bound Dsg1-coated microbeads. Rather, our experiments strongly indicate that PF-IgG–mediated dissociation events must involve autoantibody-triggered cellular signaling pathways, resulting in destabilization of Dsg1-based adhesive sites and desmosomes.
Jens Waschke, Paola Bruggeman, Werner Baumgartner, Detlef Zillikens, Detlev Drenckhahn
Guidelines: The Editorial Board will only consider letters that we deem relevant and of interest to our readers. We will not post data that have not been subjected to peer review, nor will we post letters that are essentially a reiteration of another letter. We reserve the right to edit any letter for length, content, and clarity. Authors will be notified by e-mail if their letters were accepted. No appeals will be considered.
Specific requirements: All letters must be 400 words or fewer. You may enter the letter as plain text or HTML. The author's name and e-mail address are required, and will be posted with the letter. All possible conflicts of interest must be noted, even if they are not posted. If you wish to include a figure (keep in mind that non-peer-reviewed data will not be posted), please contact the editors directly at editors@the-jci.org.