Cells In Pemphigus Research Articles

Single-Cell Transcriptome Analysis Reveals Interaction between CCL19+ Inflammatory Keratinocytes and CCR7+ Dendritic Cells and B Cells in Pemphigus

Single-Cell Transcriptome Analysis Reveals Interaction between CCL19+ Inflammatory Keratinocytes and CCR7+ Dendritic Cells and B Cells in Pemphigus

108 Deciphering the immune mechanism of autoreactive B cells in pemphigus

108 Deciphering the immune mechanism of autoreactive B cells in pemphigus

T cell autoimmunity and immune regulation to desmoglein 3, a pemphigus autoantigen.

Pemphigus is a life-threatening autoimmune bullous disease mediated by anti-desmoglein IgG autoantibodies. Pemphigus is mainly classified into three subtypes: pemphigus vulgaris, pemphigus foliaceus, and paraneoplastic pemphigus. The pathogenicity of autoantibodies has been extensively studied. Anti-human CD20 antibody therapy targeting B cells emerged as a more effective treatment option compared to conventional therapy for patients with an intractable disease. On the other hand, autoreactive T cells are considered to be involved in the pathogenesis based on the test results of human leukocyte antigen association, autoreactive T cell detection, and cytokine profile analysis. Research on the role of T cells in pemphigus has continued to progress, including that on T follicular helper cells, which initiate molecular mechanisms involved in antibody production in B cells. Autoreactive T cell research in mice has highlighted the crucial roles of cellular autoimmunity and improved the understanding of its pathogenesis, especially in paraneoplastic pemphigus. The mouse research has helped elucidate novel regulatory mechanisms of autoreactive T cells, such as thymic tolerance to desmoglein 3 and the essential roles of regulatory T cells, Langerhans cells, and other molecules in peripheral tissues. This review focuses on the immunological aspects of autoreactive T cells in pemphigus by providing detailed information on various related topics.

Autoreactive T cells in pemphigus: perpetrator and target.

Pemphigus vulgaris (PV) is an autoimmune blistering disease, in which autoantibodies against epidermal cadherins, such as desmoglein (Dsg)1 and Dsg3, lead to the development of blisters and erosions on the skin and mucous membranes. Autoreactive CD4+ T cells are essential for the induction and perpetuation of the disease by interaction with B cells producing autoantibodies. PV has a strong genetic association with certain human leucocyte antigen (HLA) alleles with HLA-DRB1*04:02 and LA-DQB1*05:03 being the most prevalent in patients. Recently, genome-wide association studies have provided a new approach to identify single nucleotide polymorphisms, alongside the known association with HLA alleles. Loss of tolerance against Dsgs and other autoantigens is a critical event in the pathogenesis of PV. Epitope spreading contributes to the progression of PV, leading to an extension of the Dsg-specific autoimmune response to other molecular epitopes of autoantigens, such as desmocollins or muscarinic receptors. Alterations in CD4+CD25+ FoxP3+ regulatory T cells are thought to contribute to the development of PV representing a suitable target for therapeutic interventions. Several CD4+ T-cell subsets and cytokines are involved in the pathogenesis of PV, while Th2 cells are the extensively studied population. Recently, other T cell subsets like T follicular helper cells and Th17 have gained attention as new potential players in PV pathogenesis. The involvement of local autoantibody production in the lesional skin of PV patients in tertiary lymphoid organs is currently discussed but not yet clarified. In this study, we reviewed the current knowledge about the development, characteristics and function of autoreactive T cells in pemphigus and present current new T cell-targeted therapeutic approaches.

Autoreactive T cells in pemphigus: perpetrator and target.

Pemphigus vulgaris (PV) is an autoimmune blistering disease, in which autoantibodies against epidermal cadherins, such as desmoglein (Dsg)1 and Dsg3, lead to the development of blisters and erosions on the skin and mucous membranes. Autoreactive CD4+ T cells are essential for the induction and perpetuation of the disease by interaction with B cells producing autoantibodies. PV has a strong genetic association with certain human leucocyte antigen (HLA) alleles with HLA-DRB1*04:02 and LA-DQB1*05:03 being the most prevalent in patients. Recently, genome-wide association studies have provided a new approach to identify single nucleotide polymorphisms, alongside the known association with HLA alleles. Loss of tolerance against Dsgs and other autoantigens is a critical event in the pathogenesis of PV. Epitope spreading contributes to the progression of PV, leading to an extension of the Dsg-specific autoimmune response to other molecular epitopes of autoantigens, such as desmocollins or muscarinic receptors. Alterations in CD4+CD25+ FoxP3+ regulatory T cells are thought to contribute to the development of PV representing a suitable target for therapeutic interventions. Several CD4+ T-cell subsets and cytokines are involved in the pathogenesis of PV, while Th2 cells are the extensively studied population. Recently, other T cell subsets like T follicular helper cells and Th17 have gained attention as new potential players in PV pathogenesis. The involvement of local autoantibody production in the lesional skin of PV patients in tertiary lymphoid organs is currently discussed but not yet clarified. In this study, we reviewed the current knowledge about the development, characteristics and function of autoreactive T cells in pemphigus and present current new T cell-targeted therapeutic approaches.

To the 150 anniversary of the Military medical academy department of dermatology and venerology

Abstact. Described the stages of the formation of one of the first in Russia departments of skin and venereal diseases of the Military medical academy. S.M. Kirov. The contribution of eminent dermatovenerologists of the department leaders is noted: A.G. Polotebnova, V.M. Tarnovsky, T.P. Pavlova, P.A. Velikanova, M.G. Mgebrova, S.T. Pavlova, О.K. Shaposhnikova, A.N. Rodionov. So, A.G. Polotebnov is considered to be the founder of Russian dermatology and venereology. V.M. Tarnovsky was the initiator of the creation of the first in Europe Russian Syphilidological and Dermatological Society. T.P. Pavlov is known for his works on the histopathology of dermatoses, and also raised a large school of dermatology. S.T. Pavlov described for the first time in the world acantholytic cells in pemphigus, and Academician OK Shaposhnikov was the country’s leading specialist in immunology and histopathology of skin vasculitis. Currently, the department’s priorities are: the study of the molecular genetic basis of psoriasis, lymphoproliferative, bullous skin diseases, the study of foci of chronic infections in various dermatoses, the creation of teledermatology and teledermatohistopathology systems in medical institutions of the Ministry of Defense of the Russian Federation, pathohistology, trichology, psychodermatology, development of new external agents for the prevention and treatment of infectious skin diseases using liposomal yy technologies. It is shown that as a result of the work done, the Department of Skin and Venereal Diseases of the Military medical academy. S.M. Kirov reliably secured the status of Russia’s leading scientific and methodological center for the study and treatment of skin diseases.

The Diagnostic Value of Tzanck Test in Vesiculobullous, Pustular, and Oral Lesions in The Dermatology Clinic

Background: Vesiculobullous disorders represent a heterogeneous group of dermatoses with protean manifestations. The accurate diagnosis of bullous disorders of the skin and mucous membrane requires evaluation of clinical, histological, and immunofluorescence findings. Objective: The aim of this study was to investigate Tzanck smear findings and to determine the diagnostic value of this test in moist (erosive, vesicular, bullous, and pustular) skin and oral lesions. Patients and Methods: This cross sectional study was conducted on one hundred patients presented with vesicular, bullous, and pustular skin lesions and/or oral lesions. All patients were included from Dermatology Outpatient Clinic at Al-Zahraa University Hospital over the period from March 2018 to March 2019. Results: Positivity of multinucleated giant cells in herpetic infection, acantholytic cells in pemphigus, dyskeratotic acantholytic cells and cocci in bullous impetigo were useful landmarks in Tzanck smear. A decrease in viral shedding from herpetic lesions of longer duration may correlate with the lower sensitivity of the Tzanck smear. Therefore, in this study we excluded the lesions older than 3 days. The percentage of positivity in vesicles was much higher than that of pustules. Conclusion: According to this study, Tzanck smear was an inexpensive, simple, and rapid test and did not require any specialized laboratory equipment for evaluation of various vesiculobullous and pustular lesions either skin or mucosal one.

Possible Role for Plasmacytoid Dendritic Cells in Pemphigus.

Possible Role for Plasmacytoid Dendritic Cells in Pemphigus.

Meeting Report of the Pathogenesis of Pemphigus and Pemphigoid Meeting in Munich, September 2016

Autoimmune blistering diseases are a heterogeneous group of about a dozen complex disorders that are characterized by intraepidermal (pemphigus) and subepidermal blistering (pemphigoid diseases and dermatitis herpetiformis). The Pathogenesis of Pemphigus and Pemphigoid Meeting, organized by the Departments of Dermatology in Lübeck and Marburg and the Institute of Anatomy and Cell Biology, Munich, was held in September 2016 in Munich. The meeting brought together basic scientists and clinicians from all continents dedicating their work to autoimmune blistering diseases. Considerable advances have been made in describing incidences and prevalences of these diseases and linking comorbidities with autoantibody reactivities and clinical variants, for example, dipeptidyl peptidase-IV inhibitor-associated noninflammatory bullous pemphigoid. Although new entities are still being described, diagnosis of most autoimmune blistering diseases can now be achieved using standardized and widely available serological test systems. Various experimental mouse models of pemphigus and pemphigoid disease are increasingly being used to understand mechanisms of central and peripheral tolerance and to evaluate more specific treatment approaches for these disorders, such as molecules that target autoreactive T and B cells and anti-inflammatory mediators, that is, dimethyl fumarate, phosphodiesterase 4, and leukotriene B4 inhibitors in pemphigoid disorders, and chimeric antigen receptor T cells in pemphigus. Very recent experimental data about the immunopathology and the determinants of autoantibody formation and keratinocyte susceptibility in pemphigus were discussed. With regard to cellular mechanisms leading to the loss of cell-cell adhesion, new ideas were shared in the field of signal transduction. Major steps were taken to put the various partly contradictory and controversial findings about the effects of pemphigus autoantibodies and other inflammatory mediators into perspective and broaden our view of the complex pathophysiology of this disease. Finally, two investigator-initiated multicenter trials highlighted doxycycline and dapsone as valuable medications in the treatment of bullous pemphigoid.

Mechanisms underlying the reversal of acantholysis in pemphigus by a cholinergic receptor agonist

Objective To evaluate the reversal effect of a cholinergic receptor agonist on acantholysis in pemphigus, and to investigate its mechanism. Methods Human HaCaT keratinocytes were co-cultured with pemphigus vulgaris immunoglobulin G(PV-IgG) to establish a cell model of pemphigus, then classified into two groups to be incubated with the cholinergic receptor agonist carbachol for 12 hours (test group) or remain untreated (control group). Cell dissociation assay was performed to quantitatively estimate the reversal effect of carbachol on acantholysis, and immunofluorescence assay to qualitatively assess the changes of desmosomal proteins. Radio-immunoprecipitation assay (RIPA) lysis buffer and Triton X-100 were used to lyse HaCaT cells to obtain total proteins and cytoplasmic proteins, and Western blot was conducted to determine the expression levels of adhesion-related proteins desmoglein 3(Dsg3) and plakoglobin (PG) on the surface of HaCaT cells, as well as the phosphorylation levels of p38 mitogen activated protein kinase (p38 MAPK) and epidermal growth factor receptor (EGFR) at different time points. Quantitative polymerase chain reaction (qPCR) was performed to detect the mRNA expressions of the above surface proteins, and co-immunoprecipitation assay to qualitatively evaluate the interaction between Dsg3 and PG. Results The number of cell debris was significantly lower in the test group than in the control group (18.67±2.52 vs. 46.67±2.03,t=11.22, P<0.01). Immunofluorescence assay showed that carbachol could reverse the internalization of desmosomal molecules induced by PV-IgG. In the pemphigus cell model, the levels of total Dsg3 and PG as well as non-desmosomal Dsg3 were decreased, while the level of non-desmosomal PG increased, and the interaction between Dsg3 and PG was attenuated. When the pemphigus cell model was co-cultured with carbachol, these above changes were reversed. Carbachol also increased the mRNA levels (expressed as 2-ΔΔCt) of Dsg3 and PG from 1.428±0.215 and 1.563±0.247 in the control group to 4.974±0.948 (t=3.65,P=0.01) and 13.420±1.715 (t=6.85, P<0.01) in the test group respectively. In phosphorylation assay, carbachol inhibited the phosphorylation of EGFR, but had no significant effect on that of p38 MAPK. Conclusions The cholinergic receptor agonist carbachol can reverse acantholysis in pemphigus, likely by inhibiting the internalization of Dsg3 and PG, enhancing their expressions and interaction, and suppressing the phosphorylation of the key signaling molecule for acantholysis, EGFR. Key words: Pemphigus; Cholinergic agonists; Acantholysis; Desmoglein 3; gamma Catenin; HaCaT cells

The final destiny of acantholytic cells in pemphigus is Fas mediated

Pemphigus is an autoimmune disease characterized by the formation of intra-epidermal blisters. Patients develop auto-antibodies against desmoglein 1 and 3 proteins and induce acantholysis. This work addresses the issue of whether the Fas pathway mediates acantholysis. Furthermore, the possible suppliers of the Fas pathway were investigated. Seventeen biopsies of pemphigus patients were studied by haematoxylin and eosin staining, and apoptosis was defined by TUNEL. The expression of Fas, FasL and caspase 3 was studied by in situ hybridization and immunohistochemistry. Cell infiltrates were studied by immunofluorescence with monoclonal anti-CD3, CD4, CD8, CD19 and CD69. All of the biopsies showed intra-epidermal blisters, acantholytic cells and inflammatory infiltrates. The blisters expressed Fas, FasL and caspase 3. Cell infiltrates were composed of CD8 and a few CD4(+)CD69(+) cells. Additionally, CD19(+) cells were detected. Interestingly, the Fas expression was increased in acantholytic cells and perilesional keratinocytes. Incidentally, these cells exhibited apoptotic features. Interestingly, the CD8 cells expressed FasL. This paper presents the morphological evidence that apoptosis and acantholysis are linked. Therefore, the Fas pathway is associated with CD8 cells in pemphigus lesions.

The value of Tzanck smear test in diagnosis of erosive, vesicular, bullous, and pustular skin lesions

Tzanck smear is generally used for the diagnosis of the pemphigus group of autoimmune bullous diseases and mucocutaneous herpesvirus infections. There are only a few studies in the literature investigating its diagnostic value. We aimed to investigate Tzanck smear findings and to determine the diagnostic value of this test in moist (erosive, vesicular, bullous, and pustular) skin lesions. We also aimed to develop an algorithmic approach for the diagnosis of these types of skin lesions according to the Tzanck smear findings. Samples were stained with May-Grünwald-Giemsa and evaluated by the same dermatologist. In some patients, methylene blue and Gram staining or direct immunofluorescence examinations were additionally performed. In all of the study cases, after the evaluation of clinical and laboratory findings (including, when appropriate, potassium hydroxide examination; viral serology; bacterial and fungal cultures; histopathology; direct and indirect immunofluorescence; patch testing), the definite diagnosis was established. We also determined the sensitivity and the specificity of certain Tzanck smear findings. Tzanck smear was performed in a total of 400 patients with moist skin lesions. The sensitivities of multinucleated giant cells and acantholytic cells in herpetic infections, dyskeratotic acantholytic cells and cocci in bullous impetigo, pseudohyphae in candidiasis, acantholytic cells in pemphigus and more than 10 tadpole cells (magnification x100) in spongiotic dermatitis were 84.7%, 92%, 100%, 100%, and 81.5%, respectively. Because Tzanck smears were evaluated by the same dermatologist, no comment could be made regarding the interobserver reliability of this test and how the level of experience with this technique might affect the results. Also, the sensitivity and the specificity of Tzanck smear test findings for certain diseases could not be calculated because of an insufficient number of patients. The Tzanck smear test is an inexpensive, useful, and an easy diagnostic tool for certain skin diseases.

Expression of HLA-DR and OKT6 antigens on keratinocytes and dendritic cells in pemphigus

The expression of HLA-DR and OKT6 antigens by epidermal cells in pemphigus was examined by immunohistochemical methods using skin biopsy specimens from human patients with pemphigus vulgaris. Changes in the distribution and subpopulations of Langerhans cells were observed in lesional (involved) skin. HLA-DR-positive, OKT6-negative dendritic cells were numerous and generally confined to the margins of epidermal clefts. OKT6-positive dendritic cells were rare or absent in lesional skin. The HLA-DR-positive, OKT6-negative dendritic cells associated with intraepidermal clefts are most likely functionally active antigen-presenting cells, which may play a role in lesion development. Aberrant expression of HLA-DR molecules by keratinocytes was observed in both involved and uninvolved skin, and may function to facilitate the recognition of surface-bound pemphigus antigen(s) by immunocompetent cells.

Acantholytic cells in pemphigus. A scanning and transmission electron microscopic study.

Scanning electron microscopy (SEM) was performed on oral scrapings from seven patients with pemphigus vulgaris and one with pemphigus vegetans as well as on skin samples from one of those with pemphigus vulgaris. The unstained, fixed, critical-point dried cells were identified with the aid of a light microscope. On the basis of the surface appearance, three main types of acantholytic cells were identified: smooth-surfaced, wrinkled, and microvillous. The acantholytic cells were rounded to ovoid and some showed either a central bulging or a concavity. Small, rounded to ovoid holes or indentations (diameter 0.1-0.3 mumol) were observed on most cell surfaces. The surfaces of acantholytic cells were occasionally occupied by a few micro-organisms. Neutrophilic polymorphonuclear leucocyte/acantholytic cell rosettes were studied by SEM. No gap between acantholytic cell and surrounding leucocytes could be demonstrated. It is postulated that neutrophils may mediate the cytolysis of antibody-coated acantholytic cells. Oral scrapings from one patient with pemphigus vulgaris were collected for transmission electron microscopy (TEM). The acantholytic cells were rounded or ovoid and usually had centrally placed nuclei. Tonofilaments were either randomly distributed or concentrically arranged around the nucleus. In other acantholytic cells there was a halo containing vesicles of varying size around the nucleus. TEM findings suggest that acantholytic cells represent dead or dying cells. Both TEM and SEM findings suggest that when acantholytic cells first separate they may show variable numbers of microvilli, which are probably lost in older acantholytic cells.