Ultrastructural binding site of pemphigus foliaceus autoantibodies: comparison with pemphigus vulgaris

We studied in vivo binding sites of pemphigus foliaceus (PF) auto-antibodies by immuno-gold labelling technique, and compared them with those of pemphigus vulgaris (PV). In early acantholytic lesions of PF, the bound antibodies indicated by 5 nm protein A-colloiclal gold particles were observed on the surface of keratinocytes, with particular affinity for desmosomes and separated attachment plaques. Nondesmosomal cell surfaces were sparsely labeled with the gold particles. A similar binding pattern was seen in the epidermal sheets obtained from a PV patient utilizing the Nikolsky phenomenon. These findings indicate that both PF and PV antigen-antibody complexes are densely located on the desmosomal areas in early pemphigus lesions, suggesting the pathogenic importance of functional impairment of desmosomes by the autoantibodies.     

Evidence-based treatments in pemphigus vulgaris and pemphigus foliaceus

Treatment modalities in pemphigus vulgaris (PV) and pemphigus foliaceus (PF) are many and varied, although level 1 evidence supporting their use is limited. To date, only 2 systematic reviews exist to support the use of different treatment modalities to control this group of conditions. Overall, within the literature, the quality of trials comparing treatment modalities is poor. Cohort sizes are small, methodologies are varied, and standardized outcome measurements are lacking. The authors aim to present a comprehensive view of the level 1 evidence that exists for common treatment modalities used in PV and PF.     

Antigenic specificity of fogo selvagem autoantibodies is similar to North American pemphigus foliaceus and distinct from pemphigus vulgaris autoantibodies

Fogo selvagem (FS) is clinically, histologically, and immunopathologically similar to sporadic pemphigus foliaceus (PF, as seen in North America and Europe), although the epidemiology of these 2 diseases differs markedly. It has been proposed that FS is identical to PF but, for some reason, occurs in an endemic focus in central Brazil. If this hypothesis is correct, the autoantibodies in FS and PF should have similar antigenic specificities. We studied sera from 13 patients with FS from central Brazil, and compared them with 20 sera from patients with PF from the United States. All these sera had circulating antibodies that bound the cell surface of epithelial cells in identical patterns by indirect immunofluorescence on monkey esophagus or normal human skin. In immunoprecipitation studies none of the 13 FS sera precipitated the pemphigus vulgaris (PV) antigen from radiolabeled extracts of cultured human keratinocytes. This is similar to the findings with PF sera of which 19 of 20 sera did not react with PV antigen, but in sharp contrast to the results with PV sera which, as previously reported, all immunoprecipitate the PV antigen. Immunoblotting performed on extracts of normal human epidermis demonstrated that 7 of 20 PF sera specifically and intensely bound an approximately 160 kD polypeptide, previously identified as desmoglein I, a desmosomal glycoprotein. Similarly, 3 of 13 FS sera specifically bound a 160 kD polypeptide. Thirteen normal sera from North America, 8 normal and disease control sera from central Brazil, 11 PV sera, and 12 bullous pemphigoid sera did not specifically bind this polypeptide. Two-dimensional gel electrophoresis confirmed that the 160 kD polypeptides identified by the subgroup of PF and FS sera were identical. These studies demonstrate that, although the exact molecular specificities of the majority of PF and FS sera remain to be determined, FS autoantibodies do not bind the PV antigen and a subgroup of FS autoantibodies have molecular specificity identical to that of a subgroup of PF autoantibodies.     

Comparative study of pemphigus vulgaris and pemphigus foliaceus in Singapore

This is a retrospective study of all patients diagnosed to have pemphigus in our centre over a 3 year period. The case records of all patients with pemphigus from January 1995 to December 1997 were analysed. Fifty patients were diagnosed to have pemphigus during the study period. The diagnoses were pemphigus vulgaris in 31 patients, pemphigus foliaceus in 16, paraneoplastic pemphigus in two and IgA pemphigus in one. The average titre of anti-intercellular antibodies in patients with pemphigus vulgaris (1:96) was higher than the titre in patients with pemphigus foliaceus (1:69). The average initial dose of prednisolone required for disease control in patients with pemphigus vulgaris (62 mg/day) was significantly higher than that required for patients with pemphigus foliaceus (44 mg/day). In our study population, pemphigus vulgaris is a more severe and chronic disease than pemphigus foliaceus, as reflected in the higher titre of anti-intercellular antibodies, higher dose of systemic corticosteroids required for control of the disease, the longer duration to achieve complete remission and longer follow-up period.     

非桥粒芯糖蛋白抗体在寻常型天疱疮中的作用机制

既往发现寻常型天疱疮(pemphigus vulgaris,PV)发病机制与桥粒芯糖蛋白1(desmoglein,Dsg1)和Dsg3抗体有关,目前在PV患者中发现大量非Dsg自身免疫性抗体,包括桥粒胶蛋白1(desmocollin,Dsc1)和Dsc3、斑菲素蛋白1(plakophilin,PKP1)和PKP3、斑珠...     

The location of binding sites of pemphigus vulgaris and pemphigus foliaceus autoantibodies: a post-embedding immunoelectron microscopic study

Pemphigus is a life-threatening autommune blistering discase of skin and mucous membranes that has two major subtypes based on clinical and histolgical features, pemphigus vulgaris (PV) and pemphigus foliaceus (PF). Autoantibodies against the PV antigen (desmoglein 3) and the PF antigen (desmoglein 1) are involved in the pathogenesis of blister formation. In the present study, the location of epitopes recognized by autoantibodies of patients with PV and PF was studied by postembedding immunogold electron microscopy. PV and PF autoantibodies were observed bound predominantly to the intercellular domains of desmosomes, but not to the non-desmosomal keratinocyte cell surface. The relationship between the location of PF antigen and other constitutive desmosomal proteins. desmocollin, desmoplakin and plakoglobin, in normal human skin was investigated using a double immunogold labelling techinique. It was observed that PF antigen and desmocollin co-localize within the intercellular domain of the desmosomes. In contrast, the antibodies against desmoplakin and plakoglobin bound predominantly to the intracellular desmosomal attachment plaque with the binding site of the antibody against plakoglobin closer to the desmosomal cell membrane than that of the antibody to desmoplakin. We show that the LR White postembedded immunogold electronmicroscopy technique is convenient and easily applied to studied to studies of autoimmune bullous skin diseases. We have used it to demonstrated the precise localization of the binding sites of PV and PF autoantibodies and their reltionship with other constitutive desmosomal proteins.     

Treatment of pemphigus vulgaris and pemphigus foliaceus with mycophenolate mofetil

BACKGROUND: Mycophenolate mofetil is increasingly being used as a corticosteroid-sparing agent in immunosuppressive regimens. OBJECTIVE: To elucidate the effectiveness of mycophenolate as adjuvant therapy in the treatment of both pemphigus vulgaris and pemphigus foliaceus. DESIGN: Historical prospective study. SETTING: University hospital. PATIENTS: The study included 42 consecutive patients with pemphigus (31 with pemphigus vulgaris and 11 with pemphigus foliaceus) who had relapses during prednisone taper or had clinically significant adverse effects from previous drug therapy. RESULTS: Remission was achieved in 22 (71%) and 5 (45%) of patients with pemphigus vulgaris and pemphigus foliaceus, respectively. Partial remission was achieved in 1 (3%) and 4 (36%), respectively. The median time to achieve complete remission was 9 months (range, 1-13 months). The treatment was administered for a median of 22 months, and the median follow-up period was 22 months. Seventy-seven percent of patients had no adverse effect. Two patients had side effects severe enough to necessitate discontinuation of treatment, one because of symptomatic but reversible neutropenia and the other because of nausea. CONCLUSION: Mycophenolate is an effective and safe adjuvant in the treatment of both pemphigus vulgaris and pemphigus foliaceus.     

Neonatal pemphigus vulgaris: IgG4 autoantibodies to desmoglein 3 induce skin blisters in newborns

We report a case of neonatal pemphigus vulgaris presenting with skin lesions on the head, genital area, and right foot. Pemphigus vulgaris was diagnosed by the presence of circulating autoantibodies predominantly of the IgG4 subtype by indirect immunofluorescence microscopy and by enzyme-linked immunosorbent assay using recombinant desmoglein 3. This case demonstrates the pathogenic relevance of IgG4 autoantibodies to desmoglein 3 in the skin of neonates.     

Transplacental passage of maternal pemphigus foliaceus autoantibodies induces neonatal pemphigus

The association of maternal pemphigus foliaceus (PF) with neonatal PF is rare and may be secondary to transplacental passage of PF autoantibodies. We describe a 25-year-old patient with PF who was delivered of two consecutive babies, one with classic skin lesions of PF and another that was normal. The neonate with PF was born when the mother had widespread skin disease; the normal newborn was born when the mother was in partial remission. The titers of PF autoantibodies were higher in the mother's serum and the cord serum of the baby with PF than in the mother during partial remission and the unaffected baby. The mother and affected baby had autoantibodies to desmoglein 1. Furthermore, cord blood from the baby with PF induced skin disease when injected into mice. In this case, maternal PF was associated with neonatal PF when the titers of maternal anti-desmoglein 1 autoantibodies were elevated. The cutaneous disease in neonatal PF is due to anti-desmoglein 1 autoantibodies.     

Therapeutic effect of mizoribine on pemphigus vulgaris and pemphigus foliaceus

We evaluated the effectiveness of mizoribine, a newly developed immunosuppressive agent, as an adjuvant therapy in the treatment of both pemphigus vulgaris and pemphigus foliaceus. Eleven pemphigus patients (eight pemphigus vulgaris and three pemphigus foliaceus) received the combination therapy of prednisolone and mizoribine. Complete remission was observed in three of the eight patients with pemphigus vulgaris and in one of the three patients with pemphigus foliaceus. The four patients with complete remission had a rapid clinical response and achieved remission at a median of 11.8 months. Partial remission was achieved in two of the three patients with pemphigus foliaceus. The median time to achieve partial remission was 16.0 months. Six (55.6%) of the 11 patients with pemphigus had complete or partial remission and were able to taper their prednisolone. The cumulative probability of having a complete remission was 64.3% at 19 months of follow-up using Kaplan-Meier analysis. The effectiveness of the additional mizoribine therapy could be attributed to its corticosteroid-sparing properties as well as its immunosuppressive effects. The serum concentration titer of mizoribine was around 1.0?μg/mL 2 hours after administration. Patients who were not improved by the additional mizoribine might require a continuously higher dose of mizoribine to achieve effective therapy.