Abstract
There remain major gaps in our knowledge regarding the detailed mechanisms by which autoantibodies mediate damage at the tissue level. We have undertaken novel strategies at the interface of engineering and clinical medicine to integrate nanoscale visual and structural data using nanorobotic atomic force microscopy with cell functional analyses to reveal previously unattainable details of autoimmune processes in real-time. Pemphigus vulgaris is a life-threatening autoimmune blistering skin condition in which there is disruption of desmosomal cell-cell adhesion structures that are associated with the presence of antibodies directed against specific epithelial proteins including Desmoglein (Dsg) 3. We demonstrate that pathogenic (blister-forming) anti-Dsg3 antibodies, distinct from non-pathogenic (non-blister forming) anti-Dsg3 antibodies, alter the structural and functional properties of keratinocytes in two sequential steps - an initial loss of cell adhesion and a later induction of apoptosis-related signaling pathways, but not full apoptotic cell death. We propose a “2-Hit” model for autoimmune disruption associated with skin-specific pathogenic autoantibodies. These data provide unprecedented details of autoimmune processes at the tissue level and offer a novel conceptual framework for understanding the action of self-reactive antibodies.
Highlights
Desmosomal junctions are specialized structures critical to cellular adhesion within epithelial tissues
Functional correlates of nanostructural alteration associated with autoantibody binding To define the physiological correlates of the increase in cell stiffness induced by pathogenic, but not non-pathogenic antibody binding after the initial decrease in cell stiffness described above, we investigated whether the internal remodeling of the cytoskeleton in cells undergoing apoptosis is reflected in dynamic changes in cell structural properties measurable by Atomic force microscopy (AFM), as has been suggested [21]
In addition to visually tracking the effects of Pemphigus vulgaris (PV)-associated anti-Dsg3 autoantibody binding on cellular adhesion in high resolution and real-time, AFM can reliably detect nanostuctural changes at the intact cell surface in response to pathogenic and non-pathogenic antibody binding and downstream signaling events that allow conclusions regarding disease pathomechanisms relevant to autoimmunity
Summary
Desmosomal junctions are specialized structures critical to cellular adhesion within epithelial tissues. Of these junctions (acantholysis) can occur following autoimmune attack. Pemphigus vulgaris (PV) is a prototypical organ-specific, potentially life-threatening human autoimmune disease characterized clinically by flaccid blister formation affecting the skin and mucous membranes. Anti-Dsg autoantibodies have been shown to induce acantholysis in cultured keratinocytes [2] and blister formation in vivo in neonatal mice [3]. Anti-Dsg 1 antibodies are found in approximately 40% of PV patients, and have been linked to the development of Pemphigus foliaceus, a closely related but distinct autoimmune blistering skin disease, where they are sufficient to induce blister formation [4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
