Classic Pemphigus Research Articles

Utility of C4d Immunohistochemistry in the Diagnosis of Esophageal Pemphigus Vulgaris.

Aims. To assess the utility of C4d immunohistochemistry for esophageal pemphigus vulgaris. Methods and results. We searched for patients with a history of esophageal pemphigus vulgaris who had esophageal biopsies for routine hematoxylin and eosin (H&E) staining. A total of 8 biopsies from 7 patients were available. We also identified 18 non-pemphigus esophageal biopsies for controls. C4d immunohistochemistry was performed on each biopsy. Five of 6 (83%) biopsies with classic pemphigus vulgaris histologic findings were positive for intercellular staining at the basal layer. The negative biopsy was in a patient that had recently received high-dose corticosteroid treatment for a flare. Two biopsies with atypical histologic features for pemphigus vulgaris had negative C4d staining but positive direct immunofluorescence (DIF) studies. Various nonspecific C4d staining patterns were observed in the controls, but none showed the intercellular staining pattern that was observed in pemphigus vulgaris. Conclusions. Suprabasal clefting with acantholysis and "tombstone effect" are described histologic features of pemphigus vulgaris on H&E. However, procedural artifact may mimic these findings. Currently, the gold standard for pemphigus vulgaris is DIF, which is not always available because it cannot routinely be performed on formalin-fixed paraffin embedded tissue. Our study shows that C4d immunohistochemistry may be a useful adjunct in evaluating esophageal pemphigus vulgaris.

Significance of anti-desmocollin autoantibodies in pemphigus.

The major autoantigens for pemphigus are desmogleins (Dsgs), cell-cell adhesive structure proteins, one of the desmosomal cadherins. Recent progress in molecular biology has revealed that IgG autoantibodies of classical pemphigus react with Dsg1 or Dsg3. Desmocollins (Dscs) also belong to the cadherin supergene family that provides structure to the desmosomes and play an important role in cell-to-cell adhesion. In addition to the presence of four desmosomal Dsg isoforms, i.e. Dsg1-4, Dsc1, 2 and 3, all of which are derived from different genes, Dsc1 has been previously identified as the target antigen of IgA autoantibodies in the subcorneal pustular dermatosis (SPD)-type of intercellular IgA dermatosis. In addition to the IgA anti-Dsc1 autoantiboides, the presence of IgG anti-Dsc autoantibodies is described in patients of some autoimmune bullous diseases. In particular, the current pemphigus detecting autoantibodies to Dscs has shown a tendency in atypical variants of pemphigus. Therefore, autoantibodies against Dscs alone may cause detachment of cell-cell adhesion in the epidermis in some pemphigus. However, except for the findings of a few in vitro and in vivo studies, there is currently no clear evidence for the pathogenicity of anti-Dsc autoantibodies in pemphigus, whereas significance of anti-Dsg autoantibodies is well established. This article describes the structure and function of the Dscs, and explores the evidence regarding the pathogenic role of anti-Dsc autoantibodies in pemphigus.

A retrospective study on the clinicopathologic features of IgG/IgA pemphigus

A retrospective study on the clinicopathologic features of IgG/IgA pemphigus

Pemphigus vegetans with isolated involvement of the nose and chest: rare variant of pemphigus vulgaris

AbstractPemphigus vulgaris is chronic bullous disease that manifests as bullae and erosions of skin and mucosas, with intraepidermal suprabasal cleft formation seen in the histological examination. It has a rare variant called pemphigus vegetans, where vesicles and bullae are replaced by pustular, verrucous and hyperpigmented lesions, mainly in skin folds. The treatment is similar to that for classic pemphigus vulgaris. The authors present an exuberant case of pemphigus vegetans, covering the nose and chest exclusively, without oral or flexural lesions.

Paraneoplastic pemphigus: Retrospective study of a case series

Paraneoplastic pemphigus (PNP) is a rare condition associated with poor prognosis. It associates polymorphic mucocutaneous manifestations with neoplasia. Diagnosis is difficult because of the various clinical and histological features involved and the lack of specificity of immunological examinations. We retrospectively analyzed the records of patients presenting with PNP in the Poitou-Charentes region between 2000 and 2015. Seven patients were included. They presented 9 neoplasias (1 lymphoma, 1 melanoma, and 7 carcinomas) diagnosed from 4 months before to 25 months after the occurrence of cutaneous (6/7) and/or mucosal (6/7) polymorphic lesions. Histological examination revealed epidermal acantholysis (7/7), keratinocytic necrosis (4/7), and interface lichenoid dermatitis (5/7). Intercellular deposits of IgG and C3 or along the dermo-epidermal junction were detected with direct immunofluorescence (IF) (7/7). Four of 6 patients tested had positive indirect IF on rat bladder epithelium. Follow-up ranged from 1-132 months with a one-year survival of 85.7%. The clinical and histopathological presentations observed in our patients were polymorphic, with overlap between the clinical and histological features of PNP and classical pemphigus. Prognosis and survival appear better in our series than in the literature. It is possible that in some cases, the association of pemphigus with neoplasia was fortuitous, which might account for the better prognosis. A new consensus on the diagnostic criteria for PNP is needed to help practitioners to consensually diagnose it for prognostic or therapeutic trials.

Paraneoplastic autoimmune multiorgan syndrome (PAMS): Beyond the single phenotype of paraneoplastic pemphigus.

Paraneoplastic autoimmune multiorgan syndrome (PAMS) is characterized by a heterogenous group of signs and symptoms including severe desquamative stomatitis, a polymorphous cutaneous eruption, humoral immunity against plakin proteins, contribution of cell-mediated autoimmunity and commonly a progressive respiratory failure. Autoantibodies in PAMS target a wide array of antigens including plakins, cadherins, alpha-2-macroglobulin like 1 (A2ML1), BP180, plakophilin-3, and several neuromuscular antigens. Originally described as paraneoplastic pemphigus in 1990 due to some of its clinical and immunologic similarities to classic pemphigus (pemphigus vulgaris and pemphigus foliaceus), PAMS is a multiorganopathy with several distinct features from these classic forms of pemphigus. Epidemiologically, PAMS is associated with underlying neoplasia and has a differing HLA-II allele predisposition compared to classic forms of pemphigus. Clinically, lesion morphology is polymorphous, and lesion distribution fundamentally differs from that seen in classic pemphigus. PAMS has a significantly higher mortality rate and a poorer response to treatments typically effective in pemphigus. Histologically, PAMS is characterized by the presence of interface dermatitis, vacuolar changes, and dyskeratotic keratinocytes which are not seen in classic pemphigus. PAMS demonstrates not only intercellular IgG as seen in classic pemphigus, but the presence of linear basement membrane zone deposition. Antibodies against desmoglein 3 (Dsg3) map to a broader array of epitopes than in pemphigus vulgaris and there is a higher prevalence of complement binding anti-Dsg3 IgG autoantibodies in PAMS. Autoantibodies can in rare cases be absent in the more cell-mediated form of PAMS. Considering these numerable differences, we review the entity of PAMS, and provide similarities and differences to classic forms of pemphigus.

Desmoglein Compensation Theory: An explanations for Early Appearance of Oral Lesions as Compared to Skin Lesions in Pemphigus Vulgaris

Pemphigus is a life-threatening autoimmune blistering disease targeting skin and mucous membranes. It is clinically characterized by flaccid blisters and erosions, while histologically shows intraepithelial acantholysis. The disruption of desmoglein-dependent cell adhesion by autoantibodies is the basic pathophysiology in blister formation of pemphigus. The clinical and histological spectrum of pemphigus is complex and differs in various variants of pemphigus. This review offers an answer to why the splits associated with pemphigus foliaceus occur in the superficial layer of the epidermis, while those of pemphigus vulgaris occur deep in the epidermis. With the help of desmoglein compensation theory, it logically explains why oral erosions develop in patients with pemphigus vulgaris, but not in patients with pemphigus foliaceus and why some patients with pemphigus vulgaris have only oral involvement, but others have extensive lesions on both skin and mucous membranes. Learning objective: After completing this article, readers shall be familiar with the clinical presentations, histologic findings, immunopathology of classical pemphigus and its variants. It discusses the desmoglein compensation theory of pathogenesis. along with the management of pemphigus.

Anti-desmocollin autoantibodies in nonclassical pemphigus.

Despite the established pathogenic role of anti-desmoglein (Dsg) antibodies in classical pemphigus, the significance of autoantibodies to another desmosomal cadherin, desmocollin (Dsc) is at present unknown. No consistent immunoassay for immunoglobulin (Ig) G autoantibodies to Dscs has been developed. The aim of this study was to develop reliable assays to detect anti-Dsc autoantibodies. We expressed soluble recombinant proteins (RPs) of human Dsc1-3 in mammalian cells and examined sera of various types of pemphigus, including 79 paraneoplastic pemphigus (PNP) sera, by novel enzyme-linked immunosorbent assays (ELISAs) using the RPs. We also performed ELISAs of Dsc baculoproteins and used the complementary DNA (cDNA) transfection method, and compared the results with those of mammalian ELISAs. Through mammalian ELISAs, IgG autoantibodies to Dsc1, Dsc2 and Dsc3 were detected in 16.5%, 36.7% and 59.5% of PNP sera, respectively, and considerable numbers of pemphigus herpetiformis (PH) and pemphigus vegetans (PVeg) sera reacted strongly with Dsc1 and Dsc3. Mammalian ELISAs were highly specific and more sensitive than baculoprotein ELISAs or the cDNA transfection method. Several Dsc-positive sera, particularly PH sera, showed no reactivity with Dsgs. The reactivity of PNP serum and PVeg serum with Dscs was not abolished by pre-absorption with Dsg RPs. The results of these novel ELISAs indicated that IgG anti-Dsc autoantibodies were frequently detected and potentially pathogenic in nonclassical pemphigus.

Five Japanese cases of antidesmoglein 1 antibody‐positive and antidesmoglein 3 antibody‐negative pemphigus with oral lesions

Oral mucosal lesions develop in pemphigus vulgaris, but not in pemphigus foliaceus. This clinical phenomenon is explained by the 'desmoglein (Dsg) compensation theory'. Dsg3 and Dsg1 are major autoantigens for pemphigus vulgaris and pemphigus foliaceus, respectively. Dsg3 is overexpressed and Dsg1 is weakly expressed on the oral mucosa. Thus, on the oral mucosa, suppression of Dsg3 function by anti-Dsg3 autoantibodies is not compensated by weakly expressed Dsg1 in pemphigus vulgaris, while suppression of Dsg1 function by anti-Dsg1 autoantibodies is perfectly compensated by richly expressed Dsg3 in pemphigus foliaceus. We present five Japanese patients with pemphigus who deviate from this theory, i.e. all patients showed oral lesions (three also had cutaneous lesions) and reacted only with Dsg1, but not with Dsg3, by enzyme-linked immunosorbent assay. To confirm whether the unique clinical phenotypes in our patients were due to a different immunological profile from that in classical pemphigus, we examined the reactivity of the patient sera by immunoprecipitation-immunoblotting analysis using five Dsg1/Dsg2 domain-swapped molecules. The sera of two patients who had only oral lesions tended to react with the extracellular (EC) 5 domain of Dsg1, the domain that is considered nonpathogenic in classical pemphigus foliaceus. Sera of three patients with mucocutaneous lesions reacted with EC1 domain or with both EC1 and EC2 domains of Dsg1, like classical pemphigus foliaceus. These results indicate that antigenic diversity of anti-Dsg1 antibodies in these patients may cause the unique oral mucosal and cutaneous lesions, although further studies are required to elucidate the pathomechanisms.

Epitope Spreading Is Rarely Found in Pemphigus Vulgaris by Large-Scale Longitudinal Study Using Desmoglein 2–Based Swapped Molecules

Epitope spreading is involved in inducing and maintaining self-reactivity. Epitope spreading in pemphigus vulgaris (PV), caused by IgG autoantibodies to desmoglein 3 (Dsg3) and Dsg1, was previously analyzed using Dsg3/Dsg1 extracellular domain-swapped molecules. However, precise identification of the responsible epitopes in each molecule by using only this method was problematic. In this study, we studied epitope spreading in PV by a novel immunoprecipitation-immunoblot method using Dsg3 (or Dsg1)/Dsg2 domain-swapped molecules, which overcomes the problems associated with the previous approaches. We analyzed the antigenic epitopes recognized by 212 sera collected from 53 PV patients at multiple disease stages. The major epitopes were present at the N-terminal region of Dsgs and were unchanged over the course of the disease in both anti-Dsg3 mucosal dominant-type PV and anti-Dsg3/Dsg1 mucocutaneous-type PV. These N-terminal epitopes were calcium dependent. Circulating antibodies in paraneoplastic pemphigus and pemphigus herpetiformis had unique epitope distributions, although the Dsg N-termini still contained the major epitopes. These results suggest that, after onset, intramolecular and intermolecular epitope spreading among extracellular domains on Dsg3 and Dsg1 is rare in PV and has no correlation with disease course.

How does acantholysis occur in pemphigus vulgaris: a critical review

Pemphigus vulgaris is a life-threatening autoimmune blistering disease targeting skin and mucous membranes, characterized by disruption of keratinocytes' adhesion termed acantholysis. Today multiple classes of targets are considered to play a role in the genesis of the acantholysis; of these, the classical pemphigus antigens, desmosomal cadherins (desmoglein 1 and 3) are the best characterized and considered as the most important. Additional antigens include the novel epithelial acetylcholine receptors (alpha9 and pemphaxin). Thus, acantholysis in pemphigus seems to result from a cooperative action of antibodies to different keratinocyte self-antigens, but the mechanisms by which epithelial cleft occurs are not yet clearly understood. In fact, the binding of the autoantibodies to these targets generates a plethora of biological effects due, on one hand, to their direct interference with adhesive function and, on the other, to more complex events involving intracellular pathways that modify proteases activity or calcium metabolism, leading to loss of cell-cell adhesion.

Paraneoplastic autoimmune multiorgan syndrome: Review of the literature and support for a cytotoxic role in pathogenesis

Paraneoplastic autoimmune multiorgan syndrome (PAMS), first described as paraneoplastic pemphigus in 1990, is an autoimmune blistering disease associated with neoplasia. Patients with this rare disorder have severe blistering and painful erosions of the oral cavity and various other cutaneous findings ranging from classic pemphigus vulgaris-like erosions to targetoid lesions resembling erythema multiforme and papular to more confluent lichenoid eruptions. This syndrome involves multiple organ systems, and its high rate of mortality often stems from constrictive bronchiolitis obliterans. The histologic findings are as diverse as the clinical presentation, often making diagnosis difficult initially. Immunodermatologic and serologic laboratory findings typically establish the diagnosis. These results can be confirmed with immunoprecipitation profiling of specific molecular weight protein markers. The proposed pathogenesis of PAMS continues to evolve, and recent reports implicate the involvement of cell-mediated, cytotoxic immunity, in addition to humoral autoantibodies. This review characterizes and summarizes the clinical, pathologic, and immunohistologic features of PAMS and outlines the possible role of cytotoxic T lymphocytes in the pathogenesis of this syndrome.

The detection of IgG and IgA autoantibodies to desmocollins 1-3 by enzyme-linked immunosorbent assays using baculovirus-expressed proteins, in atypical pemphigus but not in typical pemphigus.

We have shown previously that human desmocollin (Dsc) 1 is recognized by IgA autoantibodies of subcorneal pustular dermatosis (SPD) type IgA pemphigus. However, the presence of IgG anti-Dsc autoantibodies is still controversial, and antibodies to Dsc2 and Dsc3 have not been clearly identified. To investigate this by producing recombinant proteins consisting of the entire extracellular domains of human Dsc1, 2 and 3 in baculovirus, and to use them to establish an enzyme-linked immunosorbent assay (ELISA). By this ELISA, we examined in total 165 cases of various types of autoimmune bullous diseases, as well as 23 normal controls. None of 45 sera of classical pemphigus showed either IgG or IgA antibodies to any Dsc. In contrast, one atypical pemphigus serum showed both IgG and IgA antibodies to Dsc1, which were adsorbed by incubation with Dsc1 baculoprotein. Furthermore, this ELISA detected both IgA and IgG anti-Dsc3 antibodies in one atypical case, and IgA antibodies to both Dsc2 and Dsc3 in another. This reactivity was confirmed by positive IgA immunofluorescence with Dsc2 and Dsc3 expressed on COS-7 cells. These results show that both IgG and IgA autoantibodies against all of Dsc1-3 are present in the sera of particular cases of nonclassical pemphigus, except for IgG antibodies to Dsc2, but that they are not detected in classical pemphigus. Unexpectedly, although IgA antibodies of all of eight SPD type IgA pemphigus sera reacted with Dsc1 expressed on COS-7 cells, only one serum was positive in Dsc1 ELISA for IgA. This result indicates either that Dscs expressed by baculovirus may not adopt the correct conformation or that Dscs may need association with other molecules to express all the epitopes for autoantibodies.

Human Desmocollin 1 (Dsc1) Is an Autoantigen for the Subcorneal Pustular Dermatosis Type of IgA Pemphigus

IgA pemphigus showing IgA anti-keratinocyte cell surface autoantibodies is divided into subcorneal pustular dermatosis (SPD) and intraepidermal neutrophilic IgA dermatosis (IEN) types. We previously showed by immunoblotting that IgA from some IgA pemphigus patients reacted with bovine desmocollins (Dsc), but not human Dsc. To determine the antigen for IgA pemphigus, we focused on conformation-dependent epitopes of Dsc, because sera of patients with classical pemphigus recognize conformation-sensitive epitopes of desmogleins. We constructed mammalian expression vectors containing the entire coding sequences of human Dsc1, Dsc2, and Dsc3 and transiently transfected them into COS7 cells by lipofection. Immunofluorescence of COS7 cells transfected with single human Dscs showed that IgA antibodies of all six SPD-type IgA pemphigus cases reacted with the surface of cells expressing Dsc1, but not with cells expressing Dsc2 or Dsc3. In contrast, none of seven IEN-type IgA pemphigus cases reacted with cells transfected with any Dscs. These results convincingly indicate that human Dsc1 is an autoantigen for SPD-type IgA pemphigus, suggesting the possibility of an important role for Dsc1 in the pathogenesis of this disease. This study shows that a Dsc can be an autoimmune target in human skin disease.

Pemphigus herpetiformis is a rare clinical expression of nonendemic pemphigus foliaceus, fogo selvagem, and pemphigus vulgaris

Background: Pemphigus herpetiformis is a rare and atypical variant of pemphigus that resembles dermatitis herpetiformis. Most patients show antiepidermal autoantibodies that stain the epidermal intercellular spaces by immunofluorescence, similar to pemphigus autoantibodies, and lack the immunopathologic features of dermatitis herpetiformis. Objective: The study was aimed at characterizing the specificity of the antiepidermal autoantibodies in seven patients with pemphigus herpetiformis. Methods: The antiepidermal autoantibodies were characterized by immunofluorescence, immunoblotting, and immunoprecipitation studies in seven patients who fulfilled the clinical, histologic, and immunofluorescence diagnostic criteria for pemphigus herpetiformis. Results: Five patients with features of pemphigus herpetiformis either had classic pemphigus foliaceus, or their disease evolved into classic pemphigus foliaceus. One of these patients had fogo selvagem. Two of the seven patients showed features of or had disease that evolved into pemphigus vulgaris. The antiepidermal autoantibodies present in all seven patients recognized desmoglein 1. Conclusion: Pemphigus herpetiformis is a rare clinical and histologic expression of nonendemic pemphigus foliaceus, fogo selvagem, and pemphigus vulgaris.

Paraneoplastic pemphigus: a subset of patients with pemphigus and neoplasia

We reviewed the clinical, histologic, and immunofluorescence features of 20 patients with pemphigus and neoplasia and compared them with a control group of 17 patients with pemphigus without neoplasia. Patients with neoplasia were divided according to clinical, histologic, and immunofluorescence findings into those with paraneoplastic pemphigus syndrome (12 patients) and those with classic pemphigus vulgaris or pemphigus foliaceus with neoplasia (8 patients). The histologic findings in patients with paraneoplastic pemphigus included acantholysis, interface dermatitis, spongiosis, and satellite keratinocyte necrosis. Histologic findings in the 8 patients with classic pemphigus and neoplasia included acantholysis and spongiosis. Direct immunofluorescence in both paraneoplastic pemphigus and pemphigus with neoplasia showed IgG staining of cell-surface proteins (intercellular substance) and deposition of immunoglobulin at the basement membrane zone. Indirect immunofluorescence with rat bladder substrate was used to differentiate paraneoplastic pemphigus from classic pemphigus. Circulating IgG anti-cell-surface protein antibodies were detected in 4 patients with paraneoplastic pemphigus syndrome; they were absent in 2 patients with pemphigus and neoplasia. Immunoprecipitation of sera from the 4 patients with epithelial staining showed the complex of bands identified in studies of paraneoplastic pemphigus syndrome. We conclude that paraneoplastic pemphigus syndrome has distinct clinical, histologic, and immunologic features that differentiate it from classic pemphigus with underlying neoplasia.

Production of a human monoclonal anti-epithelial cell surface antibody derived from a patient with pemphigus vulgaris

The production of monoclonal autoantibodies derived from individuals with autoimmune diseases constitutes a powerful tool to analyse an autoimmune process at both the antigen and antibody levels. We established a human anti-epithelial cell surface monoclonal antibody by applying hybridoma technology using peripheral blood lymphocytes from a patient with pemphigus vulgaris using a heteromyeloma as the fusion partner. The F12 monoclonal antibody displays four major characteristics: (1) it belongs to the IgM, kappa class; (2) it binds to the cell surface of stratified squamous and simple epithelia; (3) it recognizes an antigenic determinant associated with the desmosomal complex as demonstrated by indirect immunoelectron microscopy; (4) by immunoblotting analysis, it reacts with a 185 kDa polypeptide which was also recognized by a few pemphigus vulgaris sera. Although the F12 monoclonal antibody does not have the immunochemical properties of classical pemphigus vulgaris autoantibodies, several arguments suggest its relevance to the pemphigus vulgaris autoimmune response and, therefore, the heterogeneity of the antigen/antibody systems involved in this autoimmune disorder.

The clinical and histopathological spectrum of IgA-pemphigus-report of two cases

Two new cases of neutrophilic bullous disease exhibiting bound and circulating intercellular IgA in vivo in both direct and indirect immunofluorescence (IF), for which the term IgA-pemphigus was recently proposed, are presented. The first case showed a unique constellation of clinical and histopathological features not previously described for IgA-pemphigus, resembling both dermatitis herpetiformis and pemphigus, for which the designation IgA-herpetiform pemphigus seems most appropriate. The second case showed clinical and histopathological features mimicking subcorneal pustular dermatosis for which the previously used term IgA-pemphigus foliaceus seems most appropriate. The previously reported 11 cases showing similar direct IF findings, as well as our two patients, illustrate the main differences between IgA-pemphigus and classic forms of this condition: (a) different clinical manifestations with the absence of Nikolsky's sign; (b) scanty acantholysis; an abundance of neutrophils, with occasional neutrophilic spongiosis; (c) absence of C3 on direct IF; (d) the lower sensitivity of indirect IF and low levels of circulating antibodies; (e) the relatively benign course of the disease; (f) the apparent responsiveness to sulphones in many cases. It is suggested that IgA pemphigus should be considered as an entity separate from, but closely related to, classic pemphigus.

Pemphigus induit par la D-pénicillamine

The authors describe a new original observation of a D-penicillamine-induced pemphigus in a patient with rheumatoid polyarthritis. It begins in two steps: the first crisis of blisters having subsided after withdrawal of D-penicillamine, there is a recurrence 7 months later. Clinical and histopathological aspects of pemphigus vulgaris are discussed. Existence of intercellular antisubstance antibody in the serum and in the skin. Evolution identical to that of a classical pemphigus requiring an important corticotherapy. Review of the literature on the previous cases of D-penicillamine-induced pemphigus and other pemphigus attributed to the action of other drugs, namely pyritinol, rifampicine and practolol. Discussion of the pathogenesis.