The nature and pathogenesis of dyskeratosis in Hailey-Hailey's disease and Darier's disease

Hailey–Hailey Disease: Identification of Novel Mutations in ATP2C1 and Effect of Missense Mutation A528P on Protein Expression Levels

ATP2C1, encoding the human secretory pathway Ca(2+)-ATPase (hSPCA1), was recently identified as the defective gene in Hailey-Hailey disease (HHD), an autosomal dominant skin disorder characterized by abnormal keratinocyte adhesion in the suprabasal layers of the epidermis. In this study, we used denaturing high-performance liquid chromatography to screen all 28 exons and flanking intron boundaries of ATP2C1 for mutations in 9 HHD patients. Nine different mutations were identified. Five of these mutations, including one nonsense, one deletion, two splice-site, and one missense mutation, have not been previously reported. Recently, functional analysis of a series of site-specific mutants, designed to mimic missense mutations found in ATP2C1, uncovered specific defects in Ca(2+) and/or Mn(2+) transport and protein expression in mutant hSPCA1 polypeptides. In order to investigate the molecular and physiological basis of HHD in the patient carrying missense mutation A528P, located in the putative nucleotide binding domain of the molecule, site-directed mutagenesis was employed to introduce this mutation into the wild-type ATP2C1 (hSPCA1) sequence. Functional analyses of HHD-mutant A528P demonstrated a low level of protein expression, despite normal levels of mRNA and correct targeting to the Golgi, suggesting instability or abnormal folding of the mutated hSPCA1 polypeptides. Analogous to conclusions drawn from our previous studies, these results further support the theory of haploinsufficiency as a prevalent mechanism for the dominant inheritance of HHD, by suggesting that the level of hSPCA1 in epidermal cells is critical.

The intraepidermal blistering conditions

The intraepidermal vesiculobullous disorders constitute a wide variety of pathogenically unrelated disorders that share in common the formation of cleft or bullae formation within the epithelium. The etiologic, pathogenic, clinical and, in particular, the histopathologic attributes of the most important intraepidermal blistering conditions are described.

Impaired trafficking of the desmoplakins in cultured Darier's disease keratinocytes

Darier's disease is an autosomal dominantly inherited skin disorder characterized by loss of adhesion between epidermal cells, breakdown of desmosome-keratin filaments, and abnormal keratinization. ATP2A2 has been identified as the causative gene of Darier's disease. This gene encodes the sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) isoform 2 pump, which transports Ca2+ from the cytosol into the endoplasmic reticulum lumen to maintain a low cytosolic Ca2+ concentration. Using indirect immunofluorescence and biochemical analysis, we investigated the distribution of key desmosomal proteins in normal human and Darier's disease keratinocytes under various calcium conditions. We show that inhibition of SERCA by thapsigargin in normal human keratinocytes impairs the trafficking of the desmoplakins, desmoglein, and desmocollin to the cell surface; these proteins show a diffuse cytoplasmic distribution and, together with plakoglobin, form detergent-insoluble aggregates. In Darier's disease keratinocytes, only the trafficking of desmoplakin is significantly inhibited; in these cells, desmoplakin forms insoluble aggregates when extracted with mild detergent. In contrast, the transmembrane proteins desmoglein and desmocollin are efficiently transported to the cell surface. These proteins, along with plakoglobin, remain equally distributed between detergent-soluble and -insoluble fractions. We also demonstrate an interaction between SERCA2 and desmoplakin during differentiation. Our results provide further insights into the critical role of calcium ATPases in maintaining epidermal integrity.

Hailey-Hailey disease: molecular and clinical characterization of novel mutations in the ATP2C1 gene

Hailey-Hailey disease is an autosomal dominant skin disorder characterized by suprabasal cell separation (acantholysis) of the epidermis. Mutations in ATP2C1, the gene encoding a novel, P-type Ca2+-transport ATPase, were recently found to cause Hailey-Hailey disease. In this study, we used conformation-sensitive gel electrophoresis to screen all 28 translated exons of ATP2C1 in 24 Hailey-Hailey disease families and three sporadic cases with the disorder. We identified 22 different mutations, 18 of which have not previously been reported, in 25 probands. The novel mutations comprise three nonsense, six insertion/deletion, three splice-site, and six missense mutations and are distributed throughout the ATP2C1 gene. Six mutations were found in multiple families investigated here or in our previous study. Haplotype analysis revealed that two of these are recurrent mutations that have not been inherited from a common ancestor. Comparison between genotype and phenotype in 23 families failed to yield any clear correlation between the nature of the mutation and clinical features of Hailey-Hailey disease. The extensive interfamilial and intrafamilial phenotypic variability observed suggests that modifying genes and/or environmental factors may greatly influence the clinical features of this disease.

Dissociation of intra- and extracellular domains of desmosomal cadherins and E-cadherin in Hailey-Hailey disease and Darier's disease

In order to clarify the pathomechanism of acantholysis in Hailey-Hailey disease (HHD) and Darier's disease (DD), the distribution of desmosomal and adherens junction-associated proteins was studied in the skin of patients with HHD (n = 4) and DD (n = 3). Domain-specific antibodies were used to determine the cellular localization of the desmosomal transmembrane glycoproteins (desmogleins 1 and 3 and desmocollin), desmosomal plaque proteins (desmoplakin, plakophilin and plakoglobin) and adherens junction-associated proteins (E-cadherin, alpha-catenin, beta-catenin and actin). A significant difference in staining patterns between intra- and extracellular domains of desmosomal cadherins and E-cadherin was demonstrated in acantholytic cells in both HHD and DD, but not in those in pemphigus vulgaris and pemphigus foliaceus samples used as controls. In acantholytic cells in HHD and DD, antibodies against attachment plaque proteins and intracellular epitopes of desmosomal cadherins exhibited diffuse cytoplasmic staining, whereas markedly reduced staining was observed with antibodies against extracellular epitopes of the desmogleins. Similarly, membrane staining of an intracellular epitope of E-cadherin was preserved, while immunoreactivity of an extracellular epitope of E-cadherin was destroyed. While the DD gene has been identified as ATP2A2, the gene for HHD has not been clarified. The dissociation of intra- and extracellular domains of desmosomal cadherin and E-cadherin is characteristic of the acantholytic cells in HHD and DD, and not of pemphigus. This common phenomenon in HHD and DD might be closely related to the pathophysiological mechanisms in both conditions.

1alpha,24-dihydroxyvitamin D3 (tacalcitol) is effective against Hailey-Hailey disease both in vivo and in vitro

We report a case of Hailey-Hailey disease (HHD) in which 1alpha, 24-dihydroxyvitamin D3 (tacalcitol) was effective both clinically (in vivo) and in explant cultures (in vitro) of a skin lesion. The patient was a 65-year-old man with HHD lesions in the axillary and inguinal areas bilaterally. We applied ointment containing 1alpha, 24-dihydroxyvitamin D3 (tacalcitol), an analogue of active vitamin D3, to the lesions and assessed its clinical effectiveness. The HHD lesions in both groins disappeared after treatment with the 1alpha, 24-dihydroxyvitamin D3 ointment, and the remission has continued to the present. A punch biopsy specimen of the lesion that had remitted showed no acantholysis. In addition, dissociation of migrating keratinocytes was observed when biopsy specimens of the HHD skin lesion were cultured in medium without 1alpha,24-dihydroxyvitamin D3, but inhibition of keratinocyte dissociation was observed in medium containing it. These results suggest the effectiveness of 1alpha, 24-dihydroxyvitamin D3 against HHD both in vivo and in vitro.

Ultrastructural localization of cell junctional components (desmoglein, plakoglobin, E-cadherin, and beta-catenin) in Hailey-Hailey disease, Darier's disease, and pemphigus vulgaris

The distribution of desmoglein, plakoglobin, E-cadherin, and beta-catenin in the peri-lesional and lesional skin of Hailey-Hailey disease, Darier's disease, and pemphigus vulgaris was examined by immunoelectron microscopy. In the peri-lesional skin, the immunolabeling of these desmosomal components was localized to desmosomes. Adherens junction-associated E-cadherin and beta-catenin were at the cell periphery, excluding desmosomes. The labeling pattern was similar among these diseases, but the labeling intensity particularly that of plakoglobin in Hailey-Hailey disease and Darier's disease, was less than that of normal controls, suggesting that these glycoproteins are quantitatively less concentrated in the normal epidermis of these inherited diseases. In the acantholytic cells of Hailey-Hailey disease and Darier's disease the immunolabeling of the components of desmosomes was diffusely distributed in the cytoplasms, whereas that of adherensjunction was mostly at the cell periphery and partly diffusely in the cytoplasm. In contrast, desmosomes of detaching keratinocytes in pemphigus vulgaris still showed the labeling of desmoglein and plakoglobin. These findings suggest that the inherited acantholytic diseases, i.e., Hailey-Hailey disease and Darier's disease have a different pathogenesis from that of autoimmune acantholysis in pemphigus vulgaris: The intracellular components of desmosomes may primarily be disrupted in the genetic acantholytic diseases in the initial stages of acantholysis. Several unsolved questions in the previous light microscopic immunofluorescence studies using the same antibodies are now answered: 1) the diffusion of desmosomal proteins is not due to the internalization of desmosomes, 2) intracellular components of adherens junction are also finally dissolved, 3) diffuse cytoplasmic immunofluorescence patterns of desmosomal components could be explained by immunoelectron microscopy as those attached to cell membrane and trapped in tonofilament aggregates.

Involvement of the adherens junction-actin filament system in acantholytic dyskeratosis of Hailey-Hailey disease. A histological, ultrastructural, and histochemical study of lesional and non-lesional skin

Hailey-Hailey disease is a blistering genodermatosis that shows acantholytic dyskeratosis throughout the epidermis. The aim of our study was to investigate the involvement of adherens structures and cytofilaments in this particular type of acantholysis. Both lesional and non-lesional skin from 18 patients was studied histologically and ultrastructurally. Additionally, the samples were stained for desmosomes, adherens junctions, keratin filaments, actin filaments, and actin-associated proteins, and finally investigated with an electron and a confocal laser scanning microscope (CLSM), respectively. Acantholytic dyskeratosis was not only confined to lesions, but was also focally detectable in clinically unaffected skin. Despite disruption and internalization of the desmosomes, keratinocytes remained linked together by well-preserved adherens junctions. Staining for actin filaments with fluorochrome-labeled phalloidin showed a remarkable formation of actin stress fibers in these keratinocytes. Thus, incomplete acantholysis, as demonstrable in both lesional and non-lesional skin of Hailey-Hailey patients, may be due to a cohesive function of the adherens junction-actin system succeeding the dissolution of desmosomes. Most remarkably, none of the adnexal epithelia expressed the intrinsic defect of cell adhesion. This finding offers an explanation for the successful treatment of Hailey-Hailey disease by dermabrasion, which after complete removal of the involved epidermis results in reepithelialization from skin appendages.

Desmosomal dissolution in Grover's disease, Hailey-Hailey's disease and Darier's disease

Proteins involved in the formation of desmosomes and simpler adherens junctions were studied in three types of non-immune acantholytic diseases; specifically, four cases of Grover's disease (GD), one case of Hailey-Hailey's disease (HHD) and one case of Darier's disease (DD), and these were compared to two cases of immune-mediated acantholytic disease pemphigus vulgaris (PV). The proteins studied included: 1. The intracellular desmosomal proteins, desmoplakin I and II and plakoglobin; 2. The intercellular desmosomal proteins, desmoglein and CD44; and 3. vinculin, which is a major intracellular protein of the simpler aherens junctions. In GD, HHD and DD, immunostaining showed a loss of desmoplakin I and II and plakoglobin from the desmosomes, and a diffuse staining in the cytoplasm. In contrast, in pemphigus vulgaris, these proteins seemed intact and were localized to dot-like spots on the cell surface. Also, desmoglein, and CD44 were slightly affected in GD, and moderately affected in HHD and DD. Absence of desmosomal attachment plaques, the lack of labeling with desmoglein in the affected desmosomes and a diffusion of the labels into cytoplasm were demonstrated with electron microscopy using an immunogold technique. In PV, desmoglein III is one of the target antigens for the autoantibodies in this disease and was only partially preserved in a small number of lesional cells, while CD44 was mostly preserved. Vinculin was intact in GD, HHD and DD, but was lost in PV. This study, our previous work, and that of others, suggest that: 1. In GD, HHD and DD, the proteins of the desmosomal attachment plaque are primarily affected; 2. In PV, the intercellular glycoproteins are primarily involved; and 3. Simple adherens junctions are intact in GD, HHD and DD, but are damaged in PV.

Hailey-Hailey disease maps to a 5 cM interval on chromosome 3q21-q24

Hailey-Hailey disease (HHD) is a rare autosomal dominant genodermatosis characterized by disturbed keratinocyte adhesion. The disease has recently been mapped to a 14 cM region on chromosome 3q. We have further refined the location of the HHD gene by linkage analysis in six HHD families from Germany and Italy using 11 polymorphic microsatellite markers and found no evidence for genetic heterogeneity. We observed complete cosegregation between HHD and marker D3S1587, with a maximal lod score of 4.54. Detailed haplotype analyses allowed us to narrow the interval containing the HHD locus to 5 cM, flanked by D3S1589 and D3S1290.

Fine mapping of the Darier's disease locus on chromosome 12q

Darier's disease (DD) is an autosomal dominant genodermatosis characterized by epidermal acantholysis and dyskeratosis. We have performed genetic linkage studies in 10 families with DD (34 affected) by analyzing 14 polymorphic microsatellite markers. Our results confirm recent reports mapping the DD gene to chromosome 12q23-q24.1. Haplotype analysis of recombinant chromosomes in our families, along with previously reported data, narrow the location of the DD gene to a 5 cM interval flanked by the loci D12S354 and D12S84/D12S105. This localization allowed exclusion of two known genes, PLA2A and PAH, as candidate loci for DD. Three other gene loci (PPP1C, PMCH, PMCA1), mapping in 12q21-q24, remain potential candidates.

Cantharidin-induced acantholysis in Darier's disease: does acantholysis initiate dyskeratosis?

We have examined the action of cantharidin on the skin of patients with Darier's disease, and used immunohistological techniques to determine the distribution of desmosomal components, keratin intermediate filaments, and proteases in cantharidin-induced blisters. Cantharidin induced acantholysis, but the presence of acantholysis did not trigger the development of the characteristic warty, dyskeratotic papules in patients with Darier's disease. The distribution of desmosomal components, keratins and proteases within the acantholytic keratinocytes in the cantharidin-induced blisters was similar to that previously found in acantholytic cells within lesions of Darier's disease: peripheral staining for extracellular desmosomal components was reduced; some desmosomal components were detected diffusely in the acantholytic cells; basal cell keratin markers were expressed by some suprabasal acantholytic cells, and plasminogen was detected in association with acantholytic cells. Cleavage of desmosomes did not reveal the underlying abnormality in Darier's disease.

Hailey-Hailey disease is not allelic to Darier's disease

Hailey-Hailey (Familial Benign Chronic Pemphigus) Disease is a rare autosomal dominant disorder characterized by blisters caused by suprabasal epidermal acantholysis. Another autosomal dominant skin disease, Darier's disease, has clinical and histologic features which overlap those of Hailey-Hailey disease and recently has been mapped to chromosome 12q23-q24.1. We have used linkage analysis to test whether or not a mutation in this region might also underlie Hailey-Hailey disease. This analysis, using polymorphic loci tightly linked to Darier's disease, excluded this region as the site for the disease-causing mutation in two kindreds affected with Hailey-Hailey disease.

Darier-White disease: a review of the clinical features in 163 patients

BACKGROUND

Darier's disease is a rare, dominantly inherited genodermatosis; there have not been any large clinical studies of patients with this disease.

OBJECTIVE

Our purpose was to document the clinical features in a large group of patients with Darier's disease.

METHODS

Data were collected from 163 affected persons.

RESULTS

The onset usually occurred between the ages of 6 and 20 years. The disease has a predilection for the skin in seborrheic areas; 96% had acral signs; 6% had hypertrophic flexural involvement; and 13% had oral mucosal lesions. There was no remission. Topical therapy sometimes provided relief of symptoms but had no effect on the progress of the disease. Oral retinoids were effective, but long-term therapy was tolerated poorly. Most patients did not have other medical problems.

CONCLUSION

Although Darier's disease is a chronic and unremitting burden, most patients manage to lead a relatively normal life.

Hailey-Hailey disease: the clinical features, response to treatment and prognosis

Fifty-eight individuals with Hailey-Hailey disease were studied to delineate the clinical features, response to treatment and prognosis. The disease generally presented between the second and fourth decades, but the morphology of lesions was varied and a delay in diagnosis was common. Nail changes have not been documented in previous studies of Hailey-Hailey disease, but asymptomatic longitudinal white bands were present in the fingernails in 71% of 38 patients examined and are a helpful physical sign. The disease is predominantly flexural. Friction and heat or sweating exacerbate the lesions and pain may limit physical activities. The prognosis was assessed in 27 patients with longstanding disease and the long-term outlook is generally good. Seventeen patients had improved and the disease was static in seven patients. Three patients deteriorated with age. Topical corticosteroids with or without added antibiotics were an effective treatment.

Cell adhesion in Hailey-Hailey disease and Darier's disease: immunocytological and explant-tissue-culture studies

The pathogenesis of Hailey-Hailey disease and Darier's disease was investigated using immunocytological and explant-tissue-culture techniques. There was breakdown of the intercellular adhesions between keratinocytes in explants from clinically uninvolved skin of patients with Hailey-Hailey disease or Darier's disease. The major desmosomal components were present in the cultures and were expressed in a punctate peripheral pattern at cell-cell contact sites, but there was diffuse staining of acantholytic cells. Plasminogen, which is expressed by basal keratinocytes in normal skin, was detected in association with suprabasal acantholytic cells in skin biopsies from these diseases. Plasminogen was reversibly displaced from the cells by 6-aminohexanoic acid, suggesting that binding is mediated by a reaction with the lysine receptor on the plasminogen molecule. Plasminogen was also detected in separating cells in explant cultures and there was cytoplasmic expression of the plasminogen activator urokinase by these cells. These abnormalities are not unique to either disease and do not account for the phenotypic differences between Darier's disease and Hailey-Hailey disease, but plasmin generation may have a role in perpetuating cell separation.

Effects of steroid, retinoid, and protease inhibitors on the formation of acantholysis induced in organ culture of skins from patients with benign familial chronic pemphigus

Skin explants from two lesional areas and four normal-appearing areas of four patients with benign familial chronic pemphigus (BFCP) were organ cultured with and without various reagents. After 24-h culturing of involved skin with medium only, dissociation of keratinocytes, which was also observed prior to culturing, was exacerbated, and the epidermis became edematous, with a large section detaching from the dermis. These phenomena were not suppressed even when betamethasone, retinol acetate, or camostat mesilate (serine protease inhibitor) was added to the medium. On the other hand, in the cultures of uninvolved skin explants with medium only, widened intercellular spaces were observed 24-48 h after initiation of culture, and dissociation of keratinocytes and acantholytic clefts became apparent after 72 h. Such culture-induced acantholysis was almost completely suppressed by the addition of betamethasone, but not suppressed by the addition of retinol acetate, EDTA, N-ethylmaleimaide, or pepstatin A. Camostat and SBTI incompletely suppressed the acantholysis. These findings suggest the possibility that steroid may reduce blistering and that an organ culture of non-lesional benign familial chronic pemphigus (BFCP) skin may be useful for clarifying the pathogenesis, as well as for discovering new drugs for the treatment of BFCP. Further experiments are required to clarify the role of serine proteases in the acantholysis in this disease.

Immunolocalization of desmoglein I ("band 3" polypeptide) on acantholytic cells in pemphigus vulgaris, Darier's disease, and Hailey-Hailey's disease

Acantholysis is defined as loss of coherence between epithelial cells and is histologically shown in several bullous diseases. It was postulated that desmoglein I, one of the major transmembrane glycoproteins of the desmosome, may adhere to the attachment plaque inside the cell and contribute to desmoglea outside the cell. In this study we used a well characterized antibody against desmoglein I for immunofluorescence and immunoelectron microscopic techniques on 2 cases each of pemphigus vulgaris and Darier's disease and one case of Hailey-Hailey's disease. In the normal epidermis desmosomes were demonstrated in dotted or rim-like patterns along cell periphery on immunofluorescence study. In pemphigus vulgaris dotted or rim-like patterns were still identified in many acantholytic cells, particularly in early phase of acantholysis. In Darier's disease and Hailey-Hailey's disease, dotted or rim-like patterns were already lost in early acantholysis and immunoreactive desmoglein I proteins were observed diffusely in the cytoplasm. Immunoelectron microscopy confirmed these immunofluorescence observations. It was suggested that in pemphigus vulgaris desmoglein I is unlikely to be the primary site of acantholysis because dotted or rim-like patterns of immunoreactive desmoglein I are relatively preserved on lesional cells, whereas in genodermatoses such as Darier's disease and Hailey-Hailey's disease primary abnormalities of desmosomes may be involved in their acantholysis.

An immunohistological study of desmosomes in Darier's disease and Hailey-Hailey disease

The immunocytochemical distribution of desmosomal components was determined in involved skin from eight patients with Darier's disease, five patients with Hailey-Hailey disease and two patients with transient acantholytic dermatosis as well as skin from four normal controls. Sections were stained using monoclonal antibodies to the desmosomal proteins dp1 and dp2 (desmoplakins) and the desmosomal glycoproteins dg1 (desmoglein), and dg2 and dg3 (desmocollins). There was normal expression of desmosomal proteins and glycoproteins at the periphery of the keratinocytes in the perilesional skin in Darier's disease, in Hailey-Hailey disease and in transient acantholytic dermatosis. In the lesional skin there was reduced expression of desmosomal proteins and glycoproteins in the basaloid 'buds' at the base of the lesions, but there was bright diffuse staining of the acantholytic cells. Focal intracellular staining was detected within many of the acantholytic keratinocytes in Hailey-Hailey disease and within some of these cells in Darier's disease. Suction blisters were used to induce fresh acantholysis in lesional skin in Darier's disease and clinically uninvolved skin in Hailey-Hailey disease. The results indicated that acantholysis precedes the development of intracellular staining. Although there are immunopathological abnormalities in the distribution of desmosomal proteins and glycoproteins in both Darier's disease and Hailey-Hailey disease, the changes are probably secondary to internalization of desmosomal components with breakdown and redistribution of antigens rather than a primary deficiency in the synthesis of these proteins. Focal internalization was more widespread in Hailey-Hailey disease than in Darier's disease and the differences in the distribution of desmosomal components in these diseases confirm that they are distinct entities.