Desmocollin 3-mediated binding is crucial for keratinocyte cohesion and is impaired in pemphigus.
Desmocollin (Dsc) 1-3 and desmoglein (Dsg) 1-4, transmembrane proteins of the cadherin family, form the adhesive core of desmosomes. Here we provide evidence that Dsc3 homo- and heterophilic trans-interaction is crucial for epidermal integrity. Single molecule atomic force microscopy (AFM) revealed homophilic trans-interaction of Dsc3. Dsc3 displayed heterophilic interaction with Dsg1 but not with Dsg3. A monoclonal antibody targeted against the extracellular domain reduced homophilic and heterophilic binding as measured by AFM, caused intraepidermal blistering in a model of human skin, and a loss of intercellular adhesion in cultured keratinocytes. Because autoantibodies against Dsg1 are associated with skin blistering in pemphigus, we characterized the role of Dsc3 binding for pemphigus pathogenesis. In contrast to AFM experiments, laser tweezer trapping revealed that pemphigus autoantibodies reduced binding of Dsc3-coated beads to the keratinocyte cell surface. These data indicate that loss of heterophilic Dsc3/Dsg1 binding may contribute to pemphigus skin blistering.
Spindler
Volker
V
Institute of Anatomy and Cell Biology, University of Wuerzburg, Koellikerstrasse 6, D-97070 Wuerzburg, Germany.
Heupel
Wolfgang-Moritz
WM
Efthymiadis
Athina
A
Schmidt
Enno
E
Eming
Rüdiger
R
Rankl
Christian
C
Hinterdorfer
Peter
P
Müller
Thomas
T
Drenckhahn
Detlev
D
Waschke
Jens
J
D000911:Antibodies, Monoclonal / Q000494:pharmacology; D001323:Autoantibodies / Q000494:pharmacology; D002448:Cell Adhesion / Q000276:immunology; D002478:Cells, Cultured; D051187:Desmocollins / Q000378:metabolism* / Q000502:physiology; D051183:Desmoglein 1 / Q000378:metabolism; D006801:Humans; D015603:Keratinocytes / Q000473:pathology*; D018625:Microscopy, Atomic Force; D052898:Optical Tweezers; D010392:Pemphigus / Q000276:immunology / Q000473:pathology*; D011485:Protein Binding
D000911:Antibodies, Monoclonal; D001323:Autoantibodies; C490356:DSC3 protein, human; C495297:DSG1 protein, human; D051187:Desmocollins; D051183:Desmoglein 1