Desmosomal Cadherin Tension Loss in Pemphigus Vulgaris Mediated by the Inhibition of Active RhoA at Cell-Cell Adhesions.

Binding of autoantibodies to keratinocyte surface antigens, primarily desmoglein 3 (Dsg3) of the desmosomal complex, leads to the dissociation of cell-cell adhesion in the blistering disorder pemphigus vulgaris (PV). After the initial disassembly of desmosomes, cell-cell adhesions actively remodel in association with the cytoskeleton and focal adhesions. Growing evidence highlights the role of adhesion mechanics and mechanotransduction at cell-cell adhesions in this remodeling process, as their active participation may direct autoimmune pathogenicity. However, a large part of the biophysical transformations after antibody binding remains underexplored. Specifically, it is unclear how tension in desmosomes and cell-cell adhesions changes in response to antibodies, and how the altered tensional states translate to cellular responses. Here, we showed a tension loss at Dsg3 using fluorescence resonance energy transfer (FRET)-based tension sensors, a tension loss at the entire cell-cell adhesion, and a potentially compensatory increase in junctional traction force at cell-extracellular matrix adhesions after PV antibody binding. Further, our data indicate that this tension loss is mediated by the inhibition of RhoA at cell-cell contacts, and the extent of RhoA inhibition may be crucial in determining the severity of pathogenicity among different PV antibodies. More importantly, this tension loss can be partially restored by altering actomyosin based cell contractility. Collectively, these findings provide previously unattainable details in our understanding of the mechanisms that govern cell-cell interactions under physiological and autoimmune conditions, which may open the window to entirely new therapeutics aimed at restoring physiological balance to tension dynamics that regulates the maintenance of cell-cell adhesion.

Inheritance-Specific Dysregulation of Th1- and Th17-Associated Cytokines in Alopecia Areata.

Autoimmune diseases tend to cluster in families, suggesting genetic predisposition to autoimmunity associated with familial background. We have previously reported similarities in gene expression patterns and PTPN22 polymorphisms between alopecia areata (AA) patients and their healthy relatives, but not unrelated healthy controls. However, the spectrum of disease promoting (or preventing) pathways that may be activated in blood relatives of AA patients remains to be defined. Here, we investigated the extent to which cytokines associated with the Th1 and Th17 pathway are differentially expressed in the blood of patients with AA and its clinical subtypes in comparison to both healthy relatives as well as unrelated healthy controls. A comprehensive set of Th1- and Th17-related cytokines were evaluated by ELISA. We found a significant elevation of the Th17 inducer IL-23, the Th17 product IL-17A, the Th1 hallmark cytokine IFNγ, and TNFα, a Th1 cytokine with relevance to the Th17 pathway in AA patients, regardless of disease subtype, compared to healthy individuals. On further examination, we found that healthy family members grouped together with patients in terms of elevated Th1- and Th17-pathway cytokines in an inheritance-specific manner, distinct from unrelated controls. The elevation of Th17-associated cytokines in healthy controls related to AA patients indicates that Th1 and Th17 dysregulation in AA may be genetically based. Of note, one unrelated control displayed elevated levels of IL-17A and IL-23 similar to those detected in patients. One year after initial blood draw, areas of beard hair loss consistent with the diagnosis of AA were reported by this individual, indicating that the elevation in Th17-related cytokines may have predictive value.

Worldwide epidemiologic factors in pemphigus vulgaris and bullous pemphigoid.

Autoimmune blistering diseases such as bullous pemphigoid (BP) and pemphigus vulgaris (PV) are complex, multifactorial, and polygenic diseases, whose exact pathogenesis is difficult to pinpoint. Research aimed at elucidating the associated epidemiologic risk factors of these two diseases has been hampered by their rare disease status. Further, a lack of centralization and standardization of available data makes the practical application of this information challenging. In order to collate and clarify the available literature we comprehensively reviewed 61 PV articles from 37 different countries and 35 BP articles from 16 different countries addressing a range of disease relevant clinical parameters including age of onset, sex, incidence, prevalence, and HLA allele association. The reported incidence of PV ranged from 0.098 to 5 patients per 100,000 people, while BP ranged from 0.21 to 7.63 patients per 100,000. Prevalence of PV ranged from 0.38 to 30 per 100,000 people and BP ranged from 1.46 to 47.99 per 100,000. The mean age of onset in patients ranged from 36.5 to 71 years for PV and 64 to 82.6 years for BP. Female-to-male ratios ranged from 0.46 to 4.4 in PV and 1.01 to 5.1 in BP. Our analysis provides support for the reported linkage disequilibrium of HLA DRB1*0402 (an allele previously shown to be associated with PV) and DQB1*0302 alleles in Europe, North America, and South America. Our data also highlight that HLA DQB1*0503 (also known to be associated with PV) appears in linkage disequilibrium with DRB1*1404 and DRB1*1401, mainly in Europe, the Middle East, and Asian countries. The HLA DRB1*0804 allele was only associated with PV in patients of Brazilian and Egyptian descent. Only two HLA alleles were reported as associated with BP more than twice in our review, DQB1*0301 and DQA1*0505. Collectively, our findings provide detailed insights into the variation of disease parameters relevant to PV and BP that can be expected to inform future work aimed at unraveling the complex pathogenesis of these conditions across the globe.

Desmoglein compensation hypothesis fidelity assessment in Pemphigus.

The pemphigus group of autoimmune blistering diseases encompasses pemphigus vulgaris (PV) and pemphigus foliaceus (PF). Lesion location in pemphigus has been elegantly postulated by the Desmoglein Compensation Hypothesis (DCH), which references the distribution of desmoglein (Dsg) proteins in the epidermis along with a patient's autoantibody profile to describe three different lesion phenotypes: PF is characterized by subcorneal lesions in the presence of anti-Dsg1 antibodies only, while lesions in PV are suprabasilar and accompanied by anti-Dsg3 antibodies only in mucosal PV, or both anti-Dsg3 and anti-Dsg1 in the case of mucocutaneous PV. While the validity of this hypothesis has been supported by several studies and is prominently featured in textbooks of dermatology, a number of logical inconsistencies have been noted and exceptions have been published in several small-scale studies. We sought to comprehensively assess the extent to which patient clinical and autoantibody profiles contradict the DCH, and characterize these contradictions in a large sample size of 266 pemphigus patients. Remarkably, we find that roughly half of active PV and PF patients surveyed present with a combination of lesion morphology and anti-Dsg3/1 levels that contradict the DCH, including: patients with a cutaneous only PV presentation, mucocutaneous disease in the absence of either Dsg3, Dsg1, or both, and mucosal disease in the absence of Dsg3 or presence of Dsg1. We also find stark differences in fidelity to the DCH based on ethnicity and HLA-association, with the lowest proportion of adherence in previously understudied populations. These findings underscore the need to expand our understanding of pemphigus morphology beyond the DCH, in particular for populations that have not been a focus in previous investigation.

Case report: Documentation of cutaneous only pemphigus vulgaris without history of mucosal lesions in North America.

Background: Pemphigus is a group of autoimmune blistering diseases including Pemphigus vulgaris (PV) and Pemphigus foliaceus (PF). These conditions exhibit lesions with mucosal or mucocutaneous (PV) or cutaneous (PF) morphology, as framed by the Desmoglein Compensation Hypothesis (DCH). However, some PV patients present with solely cutaneous disease (cPV), and growing evidence suggests the existence of a cPV subtype without any history of mucosal erosions/blisters (cPVwohm), neither of which are predicted by the DCH. Methods: Participants were recruited from several outpatient clinical settings and patient support group meetings throughout the US. On intake, subjects provided blood samples and completed questionnaires regarding their disease status. Results: We report three cases of clinically and histologically confirmed cPV without history of mucosal lesions (cPVwohm). Of these patients, two do not carry the most common PV associated HLA alleles, DRB1*0402 or DQB1*0503. The same two patients also tested negative for the primary PV associated autoantibodies, anti-desmoglein 3 and anti-desmoglein 1, while in active disease status. Conclusion: We confirm the first documented individual cases of cPVwohm in North America, supporting the existence of PV patients that develop cutaneous disease without a history of mucosal lesions, challenging the fidelity of the DCH. Two of the 3 patients reported did not type for the common PV-associated HLA genes or display anti-desmoglein autoantibodies while in active disease, suggesting cPV patients may develop Pemphigus via genetic and immune mechanisms that differ from typical mucosal or mucocutaneous PV.

Patient genetics shape the autoimmune response in the blistering skin disease pemphigus vulgaris.

Background and aim: Pemphigus vulgaris (PV) is known to have one of the strongest HLA associations among autoimmune diseases. DRB1*0402 and DQB1*0503 in particular are significantly overrepresented in PV patients in certain worldwide populations. Yet, there remain significant gaps in our understanding regarding the precise link between PV-associated HLA molecules, the specificity of the autoimmune response, and clinical expression. In this study we assessed correlations between factors including HLA genotype, ethnicity, autoantibody levels, and lesion distribution in a cohort of 293 patients. Methods and population: Participants were recruited from multiple outpatient dermatology clinic settings and patient support meetings in the USA. On intake, patients provided venous blood samples and answered questionnaires regarding their current disease activity. Results: Eighty-one percent of patients typed as either DRB1*0402 or DQB1*0503 with a high prevalence of DRB1*0402 in patients of Ashkenazi Jewish or Caucasian (non-Jewish) descent (86% and 42%, respectively) and DQB1*0503 in patients of Southeast Asian descent (78%). Patients typing as HLA DRB1*0402 had higher levels of anti-desmoglein (Dsg)3 antibodies (204.6 +/- 340.5 IU/ml) than patients without DRB1*0402 (138.5 +/- 236.4 IU/ml) (p=0.03) and had mucosal only lesions more often than cutaneous only or mucocutaneous lesions. Patients typing as DQB1*0503 had higher levels of anti-Dsg1 antibodies (47.3 +/- 59.8 IU/ml) compared to other groups (27.8 +/- 43.7 IU/ml) (p=0.06) and higher rates of mucocutaneous disease than other lesion types. We also report an unexpected HLA association of DRB1*0804 in PV patients of African descent. Sixty-four percent of this population carried the DRB1*0804 allele, and presented with highly elevated levels of anti-Dsg3 (p=0.02). However, neither African heritage nor the presence of DRB1*0804 correlated with a predilection to any specific lesion morphology. Patients that carried neither DRB1*0402, nor DQB1*0503 or DRB1*0804 had the lowest levels of anti-Dsg3 antibodies (60.0 +/- 80.0 IU/ml) and the highest rate of solely cutaneous disease compared to carriers of these alleles. Conclusion: Our data illuminate the broader impact of genetic factors on disease development by showing that differences in HLA expression among patients and ethnicities play a large role in driving distinct patterns of antibody selection and disease phenotype in PV. These findings provide insights regarding clinical heterogeneity, and are relevant to developing improved, patient tailored management strategies.

Modulation of Mechanical Stress Mitigates Anti-Dsg3 Antibody-Induced Dissociation of Cell-Cell Adhesion.

It is becoming increasingly clear that mechanical stress in adhesive junctions plays a significant role in dictating the fate of cell-cell attachment under physiological conditions. Targeted disruption of cell-cell junctions leads to multiple pathological conditions, among them the life-threatening autoimmune blistering disease pemphigus vulgaris (PV). The dissociation of cell-cell junctions by autoantibodies is the hallmark of PV, however, the detailed mechanisms that result in tissue destruction remain unclear. Thus far, research and therapy in PV have focused primarily on immune mechanisms upstream of autoantibody binding, while the biophysical aspects of the cell-cell dissociation process leading to acantholysis are less well studied. In work aimed at illuminating the cellular consequences of autoantibody attachment, it is reported that externally applied mechanical stress mitigates antibody-induced monolayer fragmentation and inhibits p38 MAPK phosphorylation activated by anti-Dsg3 antibody. Further, it is demonstrated that mechanical stress applied externally to cell monolayers enhances cell contractility via RhoA activation and promotes the strengthening of cortical actin, which ultimately mitigates antibody-induced cell-cell dissociation. The study elevates understanding of the mechanism of acantholysis in PV and shifts the paradigm of PV disease development from a focus solely on immune pathways to highlight the key role of physical transformations at the target cell.

Evolutionary context of psoriatic immune skin response.

The skin is vital for protecting the body and perceiving external stimuli in the environment. Ability to adapt between environments is in part based on skin phenotypic plasticity, indicating evolved homeostasis between skin and environment. This homeostasis reflects the greater relationship between the body and the environment, and disruptions in this balance may lead to accumulation of susceptibility factors for autoimmune conditions like psoriasis. In this study, we examined the relationship between rapid, lineage-specific evolution of human skin and formation of psoriatic skin responses at the transcriptome level. We collected skin tissue biopsies from individuals with psoriasis and compared gene expression in psoriatic plaques to non-plaque psoriatic skin. We then compared these data with non-psoriatic skin transcriptome data from multiple primate species. We found 67 genes showing human-specific skin expression that are also differentially regulated in psoriatic skin; these genes are significantly enriched for skin barrier function, immunity and neuronal development. We identified six gene clusters with differential expression in the context of human evolution and psoriasis, suggesting underlying regulatory mechanisms in these loci. Human and psoriasis-specific enrichment of neuroimmune genes shows the importance of the ongoing evolved homeostatic relationship between skin and external environment. These results have implications for both evolutionary medicine and public health, using transcriptomic data to acknowledge the importance of an individual's surroundings on their overall health.

A Retrospective Study of Patient-Reported Data of Bullous Pemphigoid and Mucous Membrane Pemphigoid From a US-Based Registry.

Bullous pemphigoid (BP) and mucous membrane pemphigoid (MMP) are rare chronic autoimmune disorders characterized by subepidermal blistering. For the United States, there is a limited amount of studies in BP and MMP that address disease demographics and clinical data. In order to more comprehensively examine disease demographics and clinical factors, we performed a retrospective analysis of patient-reported data of 138 BP and 165 MMP patients enrolled in the International Pemphigus & Pemphigoid Foundation (IPPF) disease registry from 2010-2016. Patient-reported data was compared to Physician/Investigator reported data generated in our own local patient population (Western New York; 19 BP and 43 MMP patients). We confirm a female predominance in BP (M:F ratio 1:2.1) and MMP (M:F ratio 1:4.3), and a late onset within the 6th decade of life (average age at diagnosis, 59.1 ± 17.5 years for BP and 54.8 ± 11.2 years for MMP). MMP patients were significantly more likely to have a delay in diagnosis >12 months than BP patients (38 vs. 21%, respectively). Similar to other autoimmune conditions, a large number of BP (34%) and MMP (35%) patients present with other co-existing autoimmune disorders, with the most common being thyroid disease for both groups. Increased illness activity was paralleled by an increase in severe limitations of daily activities. The vast majority of of both BP and MMP patients received high intensity immunosuppression (49%). However, the majority of BP patients reported therapy with prednisone combined with other immunosuppressants (40%), while the majority of MMP patients received immunosuppressants other than prednisone (55%). With the exception of age at diagnosis, the clinical and demographic findings from both the national and local datasets were largely consistent with each other, and support those reported in other countries.

Single-cell membrane drug delivery using porous pen nanodeposition.

Delivering molecules onto the plasma membrane of single cells is still a challenging task in profiling cell signaling pathways with single cell resolution. We demonstrated that a large quantity of molecules could be targeted and released onto the membrane of individual cells to trigger signaling responses. This is achieved by a porous pen nanodeposition (PPN) method, in which a multilayer porous structure, serving as a reservoir for a large amount of molecules, is formed on an atomic force microscope (AFM) tip using layer-by-layer assembly and post processing. To demonstrate its capability for single cell membrane drug delivery, PPN was employed to induce a calcium flux triggered by the binding of released antibodies to membrane antigens in an autoimmune skin disease model. This calcium signal propagates from the target cell to its neighbors in a matter of seconds, proving the theory of intercellular communication through cell-cell junctions. Collectively, these results demonstrated the effectiveness of PPN in membrane drug delivery for single cells; to the best of our knowledge, this is the first technique that can perform the targeted transport and delivery in single cell resolution, paving the way for probing complex signaling interactions in multicellular settings.

Anti-Thyroid Peroxidase Reactivity Is Heightened in Pemphigus Vulgaris and Is Driven by Human Leukocyte Antigen Status and the Absence of Desmoglein Reactivity.

Pemphigus vulgaris (PV) belongs to an autoimmune disease cluster that includes autoimmune thyroid disease (AITD), suggesting common mechanisms driving autoimmune susceptibility. Our group has shown that PV patients exhibit significant reactivity to AITD-related anti-thyroid peroxidase (anti-TPO), and anti-TPO antibodies affect signaling pathways in keratinocytes similar to anti-desmoglein (Dsg) 3 antibodies. To further assess the relevance of anti-TPO reactivity in PV, we analyzed anti-TPO levels in 280 PV and 167 healthy control serum samples across a comprehensive set of variable and static parameters of disease activity and etiopathogenesis. PV patients have significantly higher activity rates (A.R.s) for anti-TPO than healthy controls, but levels do not differ between phases of clinical activity and remission. Patients that carry both the PV-associated human leukocyte antigen (HLA) alleles DRB1*0402 and DQB1*0503, or DQB1*0503 alone show a low prevalence of anti-TPO (A.R. 9.5 and 4.8%, respectively), while patients that lack expression of these alleles or carry DRB1*0402 alone have a much higher prevalence of anti-TPO (A.R. 23.1 and 15.8%, respectively), suggesting that the absence of DQB1*0503 may predispose patients to the development of anti-TPO antibodies. Similarly, anti-Dsg1-/3- patients have a higher anti-TPO A.R. (26.9%) than anti-Dsg1-/3+ (18.8%), anti-Dsg1+/3- (14.3%), and anti-Dsg1+/3+ (3.9%) patients. Our data suggest that anti-TPO reactivity in PV is driven by genetic markers that may be in linkage disequilibrium with the established PV-susceptibility alleles and that this association drives the selection of a combination of anti-Dsg and anti-TPO antibodies, with anti-TPO filling the gap in active patients that do not carry the established PV-associated autoantibodies and/or are lacking the established PV-HLA-susceptibility alleles.

Longitudinal Tracking of Autoantibody Levels in a Pemphigus Vulgaris Patient: Support for a Role of Anti-Desmoglein 1 Autoantibodies as Predictors of Disease Progression.

Anti-desmoglein (Dsg) 1 and -Dsg3 antibody titers have an established role in the diagnosis of the autoimmune blistering skin disease pemphigus vulgaris (PV). However, their usefulness for disease monitoring has been controversial. A recent large-scale immunoprofiling study by our group indicated that anti-Dsg1 levels may be a better predictor of disease activity than anti-Dsg3 levels, with declining levels predicting progression from active phase of disease to early remission, irrespective of lesional subtypes. Here, we report an illustrative case of a PV patient with mucocutaneous disease that was followed longitudinally for >2.5 years clinically and by serum serology. Autoantibody levels directed against both Dsg1 and -3 showed a moderate correlation with PDAI scores, supporting a correlation of Dsg1 and 3 levels with disease severity. However, while both anti-Dsg3 and -Dsg1 antibody levels demonstrated a steady parallel decline after initiation of rituximab therapy, only anti-Dsg1 antibodies fell to levels below detectability with the progression to remission, while anti-Dsg3 levels remained elevated. This case illustrates the potential key role and clinical benefit of tracking anti-Dsg1 levels to monitor and conceivably predict disease activity in patients with PV. J Drugs Dermatol. 2017;16(2):135-139..

Positive correlation of anti-herpes simplex type I virus antibody levels with pemphigus vulgaris disease status and activity in a large patient cohort.

It is well accepted that pemphigus vulgaris (PV) is genetically linked to specific HLA class II subtypes. Environmental factors, including the role of herpes simplex virus (HSV1) in disease manifestation, have also been implicated, but in a limited number of patients and with inconsistent results. To clarify an association between HSV1 and PV in a large data set, including a stratification by dynamic and static clinical parameters, including disease activity, therapy status, HLA association, and gender. Serum HSV1 IgG levels from PV patients and healthy controls were measured by ELISA. Subjects were typed for HLA class II DRB1 and DQB1 alleles, and categorized as HLA-matched if homozygous or heterozygous for either one of the known PV-susceptibility alleles, DRB1*0402 and DQB1*0503. Our data indicate that PV patients carry significantly higher levels of anti-HSV1 antibodies than healthy controls, and that this effect was more pronounced in the active phase of disease when compared to remission. A mild positive association could also be observed for carriers of the PV-associated HLA alleles versus HLA-unmatched controls, as well as for female PV patients when compared to female control subjects. Our data suggest a role of HSV1 in the expression of PV and further show that HLA status and gender may influence HSV1 susceptibility and/or expression of anti-HSV1 antibodies. Additional research with larger datasets is required to determine whether HSV is causally linked to PV pathogenesis and conclusively link HLA status and gender to HSV1 antibody levels.

Increased oxidative stress in pemphigus vulgaris is related to disease activity and HLA-association.

Pemphigus vulgaris (PV) is a rare blistering skin disorder characterized by the disadhesion of keratinocytes due to autoantibody attack against epidermal targets including desmoglein (Dsg) 3, Dsg 1 and possibly other adhesion and non-adhesion molecules. The mechanisms leading to immune-mediated pathology in PV are multifactorial and not fully understood. Recently, oxidative stress (antioxidant/oxidant disequilibrium) has been proposed as a contributory mechanism of autoimmune skin diseases, including PV. In this study, we directly assessed oxidative stress via measurement of total antioxidant capacity (TAC) using ELISA in 47 PV patients, 25 healthy controls and 18 bullous pemphigoid (BP) patients. We also performed microarray gene expression analysis on a separate set of 21 PV patients and 10 healthy controls to evaluate transcriptional dysregulation in oxidative stress-related pathways. Our data indicate that there is a significant reduction in TAC levels in PV patients compared with healthy controls, as well as BP patients. Furthermore, PV patients with active disease have significantly lower TAC levels than PV patients in remission. We also find that HLA allele status has a significant influence on oxidative stress. These findings are corroborated by microarray analysis showing differentially expressed genes involved in oxidative stress between the aforementioned groups. Collectively, our findings provide support for a role of oxidative stress in PV. Whether increased oxidative stress leads to disease manifestation and/or activity, or if disease activity leads to increased oxidative stress remains unknown. Future longitudinal studies may help to further elucidate the relationship between PV and oxidative stress.

Multiplexed autoantigen microarrays identify HLA as a key driver of anti-desmoglein and -non-desmoglein reactivities in pemphigus.

Patients with pemphigus vulgaris (PV) harbor antibodies reactive against self-antigens expressed at the surface of keratinocytes, primarily desmoglein (Dsg) 3 and, to a lesser extent, Dsg1. Conventionally, only antibodies targeting these molecules have been thought to contribute to disease pathogenesis. This notion has been challenged by a growing pool of evidence that suggests that antibodies toward additional targets may play a role in disease. The aims of this study were to (i) establish high-throughput protein microarray technology as a method to investigate traditional and putative autoantibodies (autoAbs) in PV and (ii) use multiplexed protein array technology to define the scope and specificity of the autoAb response in PV. Our analysis demonstrated significant IgG reactivity in patients with PV toward the muscarinic acetylcholine receptor subtypes 3, 4, and 5 as well as thyroid peroxidase. Furthermore, we found that healthy first- and second-degree relatives of patients with PV express autoAbs toward desmoglein and non-Dsg targets. Our analysis also identified genetic elements, particularly HLA, as key drivers of autoAb expression. Finally, we show that patients with PV exhibit significantly reduced IgM reactivity toward disease-associated antigens relative to controls. The use of protein microarrays to profile the autoAb response in PV advanced the current understanding of disease and provided insight into the complex relationship between genetics and disease development.

Evaluation of a Newly Available ELISA for Envoplakin Autoantibodies for the Diagnosis of Paraneoplastic Pemphigus.

IMPORTANCE: Paraneoplastic pemphigus (PNP) is routinely diagnosed by the presence of autoantibodies for desmoplakin by indirect immunofluorescence (IIF) on rat bladder epithelium (RBE). IIF on RBE has recently been found to be positive in select cases of other blistering disorders. A new ELISA that detects envoplakin autoantibodies has recently been developed for the diagnosis of PNP. In this study, we measure the specificity of IIF on RBE and compare it to the new ELISA. OBSERVATIONS: We measured the specificity of IIF on RBE to be 86% which is on the lower end of the previously reported specificity of 83% to 98.9%. The ELISA for envoplakin autoantibodies has a technical sensitivity of 100%, diagnostic sensitivity of 83%, and specificity of 91%. CONCLUSIONS AND RELEVANCE: This ELISA for envoplakin autoantibodies is now commercially available and technically easier to perform then the immunoblot. We recommend that this new ELISA serves as a confirmatory test in cases of a positive IIF on RBE given its higher specificity.

Cellular level robotic surgery: Nanodissection of intermediate filaments in live keratinocytes.

We present the nanosurgery on the cytoskeleton of live cells using AFM based nanorobotics to achieve adhesiolysis and mimic the effect of pathophysiological modulation of intercellular adhesion. Nanosurgery successfully severs the intermediate filament bundles and disrupts cell-cell adhesion similar to the desmosomal protein disassembly in autoimmune disease, or the cationic modulation of desmosome formation. Our nanomechanical analysis revealed that adhesion loss results in a decrease in cellular stiffness in both cases of biochemical modulation of the desmosome junctions and mechanical disruption of intercellular adhesion, supporting the notion that intercellular adhesion through intermediate filaments anchors the cell structure as focal adhesion does and that intermediate filaments are integral components in cell mechanical integrity. The surgical process could potentially help reveal the mechanism of autoimmune pathology-induced cell-cell adhesion loss as well as its related pathways that lead to cell apoptosis.

Development of a disease registry for autoimmune bullous diseases: initial analysis of the pemphigus vulgaris subset.

Pemphigus vulgaris (PV) is a rare, potentially life threatening, autoimmune blistering skin disease. The International Pemphigus and Pemphigoid Foundation (IPPF) has recently developed a disease registry with the aim to enhance our understanding of autoimmune bullous diseases with the long-term goal of acquiring information to improve patient care. Patients were recruited to the IPPF disease registry through direct mail, e-mail, advertisements, and articles in the IPPF-quarterly, -website, -Facebook webpage, and IPPF Peer Health Coaches to complete a 38-question survey. We present here the initial analysis of detailed clinical information collected on 393 PV patients. We report previously unrecognized gender differences in terms of lesion location, autoimmune comorbidity, and delay in diagnosis. The IPPF disease registry serves as a useful resource and guide for future clinical investigation.

Nanorobotic investigation identifies novel visual, structural and functional correlates of autoimmune pathology in a blistering skin disease model.

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.