Molecular analysis of HLA DRB1 and DQB1 in Italian patients with pemphigus vulgaris

HLA class II antigens in Croatian patients with pemphigus vulgaris and their correlation with anti-desmoglein antibodies

Pemphigus vulgaris (PV) is an acquired autoimmune blistering disease characterized by the production of autoantibodies targeting desmosomal cadherins, primarily desmoglein 1 and desmoglein 3, leading to acantholysis. The etiology of PV is multifactorial, including genetic susceptibility. This retrospective study aimed to evaluate the association of HLA class II alleles and PV and to examine the impact of PV-associated HLA class II alleles on the concentration of anti-desmoglein antibodies. The study group included 30 patients in whom the diagnosis of PV was confirmed by histopathological analysis, immunofluorescence findings, and ELISA testing for detecting antibodies against desmoglein 1 and desmoglein 3. HLA class II alleles were typed by polymerase chain reaction with sequence-specific primers (PCR-SSP). The control group consisted of 190 healthy volunteer blood donors. Data analysis revealed a significantly higher frequency of HLA class II alleles in our population of patients with PV, including HLA-DRB1*04:02, HLA-DRB1*14:54, HLA-DQB1*03:02, HLA-DQB1*05:03, HLA- DQA1*03:01, and HLA-DQA1*01:04, as well as a significantly lower frequency of HLA-DQA1*05:01 compared to the control group. We have also investigated the influence of risk alleles for PV, recognized in almost all study populations, HLA-DRB1*04:02 and HLA-DQB1*05:03, on the concentration of antibodies against desmogleins 1 and 3 in relation to the presence of these alleles. The results showed significantly higher levels of antibodies directed against desmoglein 3 among patients with DRB1*04:02 compared to patients without this allele. No difference was found for anti-desmoglein 1 antibodies. Regarding DQB1*05:03 allele, statistical analysis showed no differences in the concentration of anti-desmoglein antibodies in patients carrying this allele versus those without it.

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.

A systematic review and meta-analysis of HLA class II associations in patients with IgG4 autoimmunity

Autoimmune diseases caused by pathogenic IgG4 subclass autoantibodies (IgG4-AID) include diseases like MuSK myasthenia gravis, pemphigus vulgaris or thrombotic thrombocytopenic purpura. Their etiology is still unknown. Polymorphisms in the human leukocyte antigen (HLA) gene locus, particularly in HLA-DRB1, are known genetic susceptibility factors for autoimmune diseases. We hypothesized a similar role for HLA polymorphisms in IgG4-AID and conducted a systematic review and meta-analysis with case-control studies on IgG4-AID based on MOOSE/ HuGENet guidelines. Genotype (G) and allele (A) frequencies of HLA-DQB1*05 (G: OR 3.8; 95% CI 2.44-5.9; p < 0.00001; A: OR 2.54; 95% CI 1.82-3.55; p < 0.00001) and HLA-DRB1*14 (G: OR 4.31; 95% CI 2.82-6.59; p < 0.00001; A: OR 4.78; 95% CI 3.52-6.49; p < 0.00001) and the HLA-DRB1*14-DQB1*05 haplotype (OR 6.3; 95% CI 3.28-12.09; p < 0.00001/OR 4.98; 95% CI 3.8-6.53; p < 0.00001) were increased while HLA-DRB1*13 (G: OR 0.48; 95% CI 0.34-0.68; p < 0.0001; A: OR 0.46; 95% CI 0.34-0.62; p < 0.00001) was decreased in IgG4-AID patients. In conclusion, the HLA-DQB1*05, HLA-DRB1*14 alleles and the HLA-DQB1*05-DRB1*14 haplotype could be genetic risk factors that predispose for the production of pathogenic IgG4 autoantibodies and the HLA-DRB1*13 allele may protect from IgG4 autoimmunity.

Study of the association between human leukocyte antigens (HLA) and pemphigus vulgaris in Brazilian patients

BACKGROUND

Pemphigus vulgaris is a mucocutaneous blistering autoimmune disease that manifests as painful blisters or erosions on the skin and/or mucosal surfaces. IgG autoantibodies target desmoglein, playing a major role in disease pathogenesis. Genetic predisposal to pemphigus vulgaris, especially the HLA DR and DQ alleles, has been known since the 1980s. The unique constitution of the Brazilian population favors exploratory genetic studies.

METHODS

The study group included 51 patients with a confirmed diagnosis of pemphigus vulgaris from a tertiary hospital in Sao Paulo city, Sao Paulo, southeast Brazil. DNA was extracted from peripheral blood, and HLA A, B, C, DR, and DQ typing was performed. The control group was composed of a database of 297 deceased donors from the city of São Paulo typed with the same method. The statistical significance level was adjusted using the Bonferroni correction depending on the phenotypic frequencies evaluated for HLA A, HLA B, HLA C, HLA DRB1, DQA1, and HLA DQB1.

RESULTS

The alleles HLA-B*57, HLA-C*15, HLA-DRB1*04:02, HLA-DRB1*08:04, HLA-DRB1*14:01, DQA1*03:01, DQB1*03:02, and DQB1*05:03 were associated with susceptibility. Alleles HLA DRB1*04:02 and HLA-DRB1*14:01 and their respective haplotypes DRB1*04-DQA1*03:01-DQB1*03:02, and DRB1*14-DQA1*01:01-DQB1*05:03 conferred a risk of the disease.

CONCLUSIONS

The DRB1*04:02 and DQB1*05:03 alleles are associated with pemphigus vulgaris in our study as well as in various populations. The association with HLA-DRB1*08:04 in our study was confirmed to be specific to this allele and not to linkage disequilibrium to any adjacent gene. The association between HLA-B*57 and pemphigus vulgaris is reported for the first time in the present study.

Differential HLA class I and class II associations in pemphigus foliaceus and pemphigus vulgaris patients from a prevalent Southeastern Brazilian region

Genetic factors, particularly those concerning HLA class II, have been associated with the pathogenesis of pemphigus. Taking advantage of an area where pemphigus foliaceus (PF) and pemphigus vulgaris (PV) are prevalent in the northeastern region of the state of São Paulo, Southeastern Brazil, we have studied the HLA class I (A, B and C) and class II (DRB1 and DQA1/DQB1) profiles in 86 and 83 patients with PF and PV, respectively, as compared with 1592 controls from the same region. Among all the HLA alleles described herein, the more prevalent susceptibility alleles for PF were HLA-A*11, 33, -B*14; -DRB1*01:01, *01:02; -DQA1*01:02; and -DQB1*05:01. In PV patients, the HLA-B*38; -C*12; -DRB1*04:02, *08:04, *14:01, *14:04; -DQA1*03:01; and -DQB1*03:02 and *05:03 alleles were associated with susceptibility. The HLA-DRB1*01:02 allele and the HLA-DRB1*01-DQA1*01-DQB1*05 haplotype in PF patients and the HLA-DRB1*04:02 and *14:01 alleles and the HLA-DRB1*14-DQA1*01-DQB1*05 haplotype in PV patients were related with the highest etiologic fraction values. Distinct genetic patterns and not yet described HLA susceptibility/protection alleles/haplotypes profiles have been observed in this series. Our findings corroborate the differential genetic markers in PF and PV in an area where pemphigus is prevalent but not yet reported.

Evidence for pathogenicity of autoreactive T cells in autoimmune bullous diseases shown by animal disease models

Autoimmune bullous diseases (AIBDs) are characterized by blisters and erosions on the skin and/or mucous membranes, which are caused by autoantibodies directed to structural proteins of the epidermis and the epidermal basement membrane zone. This Viewpoint Essay discusses the contribution by autoreactive T cells to the pathogenesis of bullous pemphigoid, pemphigus and epidermolysis bullosa acquisita, with an emphasis on studies using active animal mouse models for these diseases. Previous studies have demonstrated that cytokines produced by autoreactive T cells, the interaction between antigen-specific T cells and B cells and the function of regulatory T cells are likely related to the pathogenesis of AIBDs. In interpreting the experimental results, the limitations of those animal models should be considered. Further understanding of the pathogenicity of autoreactive CD4(+) T cells may lead to disease-specific treatments.

Association between HLA-DRB1 polymorphisms and pemphigus vulgaris: a meta-analysis

Summary

Background Several studies have reported that HLA-DRB1 may be correlated with pemphigus vulgaris (PV), but most have been based on small samples and the results remain inconsistent and unclear.

Objectives To investigate the correlation between DRB1 and PV by a meta-analysis of case–control/nonfamily studies.

Methods PubMed, Wiley Online Library, ScienceDirect, Google Scholar, Cochrane Library, Chinese National Knowledge Infrastructure and Wanfang databases were searched for studies including: (i) ‘pemphigus’; and (ii) ‘human leukocyte antigen’, ‘HLA’, ‘major histocompatibility complex’, ‘MHC’ or ‘DRB1’. Eighteen selected studies were used in meta-analyses to evaluate DRB1 alleles and phenotypes by calculating the respective odds ratios (ORs) and 95% confidence intervals (CIs). Stratified meta-analyses and meta-regression analysis were also conducted.

Results The frequencies of three genotypes (allele and phenotype, respectively) were significantly increased in PV: DRB1*04 [P-value for comparability (Pc) < 0·00001, OR 3·61, 95% CI 2·28–5·71; Pc = 0·0002, OR 4·14, 95% CI 1·98–8·65], DRB1*08 (Pc = 0·03, OR 2·25, 95% CI 1·07–4·70; Pc = 0·0003, OR 2·46, 95% CI 1·51–4·01) and DRB1*14 (Pc < 0·00001, OR 6·47, 95% CI 4·52–9·26; Pc < 0·00001, OR 9·68, 95% CI 4·47–20·98). Three others (allele and phenotype, respectively) were significantly decreased in PV: DRB1*03 (Pc < 0·00001, OR 0·28, 95% CI 0·19–0·41; Pc = 0·0001, OR 0·25, 95% CI 0·12–0·51), DRB1*07 (Pc = 0·004, OR 0·45, 95% CI 0·26–0·78; Pc = 0·0002, OR 0·27, 95% CI 0·14–0·54) and DRB1*15 (Pc = 0·001, OR 0·35, 95% CI 0·18–0·66; Pc = 0·002, OR 0·32, 95% CI 0·16–0·65). Ethnicity partially explained the heterogeneity of DRB1*07, DRB1*08 and DRB1*14 phenotypes.

Conclusions Our findings suggest that DRB1*04, DRB1*08 and DRB1*14 are statistically significant susceptibility factors for PV. Conversely, DRB1*03, DRB1*07 and DRB1*15 may be negatively associated with PV. Specific HLA-DRB1 types may influence the susceptibility or resistance to PV, which needs further investigations.

Low-level laser therapy on the treatment of oral and cutaneous pemphigus vulgaris: case report

Pemphigus vulgaris is a chronic autoimmune mucocutaneous disease that initially is manifested by painful intraoral erosions and ulcers which spread to other mucosa and the skin, generally more than 5 months after oral lesion manifestation. The treatment consists of prednisone alone or in combination with an immunosuppressive agent, and the clinical response is perceived within 2 to 4 weeks. Low-level laser therapy has been effective in accelerating the healing of injured tissue, thus inducing cell proliferation and increasing ATP, nucleic acid, and collagen synthesis. We reported two cases of pemphigus vulgaris that received systemic treatment associated with low-level laser therapy for oral and cutaneous lesions. We observed prompt analgesic effect in oral lesions and accelerated healing of oral and cutaneous wounds. Therefore, the present report suggests LLLT as a noninvasive technique that should be considered as an adjuvant therapy in oral and skin disorders in patients with PV.

Immunogenetics of pemphigus: An update

Pemphigus are rare but informative models of organ-specific autoimmune diseases, resulting from the interplay of environmental, genetic and stochastic factors. There are many arguments to consider that pemphigus have a genetic basis involving, as many other autoimmune diseases, several different genes with additive or synergistic effects. So far, the unique strategy used to identify the contributive loci has been direct analysis of candidate genes through conventional case-control association studies. The major histocompatibility complex in particular the class II locus was demonstrated to be associated with pemphigus with a high rate of replicability. The progresses in the understanding of pemphigus physiopathology and the development of new molecular tools offer new perspectives to unveiled the genetic basis of this group of autoimmune blistering diseases, as shown by recent studies of candidate genes expressed at different levels of the autoimmune process.

Oral mucosal disease: Pemphigus

Pemphigus defines a group of rare mucocutaneous autoimmune diseases of which pemphigus vulgaris (PV) is the most common. The aetiology and pathogenesis of PV are not completely clear, but there is a fairly strong genetic background: ethnic groups such as Ashkenazi Jews and people of Mediterranean and Indian origin are particularly susceptible and there is a link to HLA class II alleles. The initiating event in PV is not clear, but circulating IgG autoantibodies develop, directed particularly against the intercellular cadherin desmoglein 3 (Dsg3) in desmosomes of stratified squamous epithelium. Oral lesions often herald the disease and are initially vesiculobullous, but they rupture readily to leave ulcers. Involvement of other mucosa and skin is almost inevitable and PV is potentially life threatening. The diagnosis is confirmed by biopsy with histological examination and immunostaining. Management is largely by systemic immunosuppression with corticosteroids, usually azathioprine or other agents, but newer treatments with potentially fewer adverse effects look promising.

HLA-DRB1*0402 haplotypes without DQB1*0302 in Venezuelan patients with pemphigus vulgaris

The two basic forms of autoimmune intraepidermal blistering diseases, pemphigus vulgaris (PV) and pemphigus foliaceus (PF), affect different layers of the skin, have different symptoms and target different antigens. We have defined human leukocyte antigen (HLA)-DRB1-DQB1 alleles and haplotypes in a case-control study of 66 non-Jewish patients attending a public reference Hospital over the past 10 years. The control group consisted of 101 matched individuals tested also by medium to high-resolution polymerase chain reaction-sequence-specific oligonucleotide with primers and probes from the 12th and 13th International Histocompatibility Workshop. Patients and controls were descendants of three-generation individuals born in the country. Among the patients, 49 had PV, 50% showed predominantly mucosal involvement, 50% showed predominantly the cutaneous clinical phenotype and 17 had PF. Statistically significant HLA-DR frequency differences between patients with PV and controls were found only for DRB1*0402 and DRB1*1401 [odds ratio (OR) = 27.22, confidence interval (CI) 94.7-7.82, P= 1.1 x 10(-14) and OR = 46.56, CI 801.4-2.70 P= 7.5 x 10(-6), respectively]. Both alleles were also increased in the patients with PF compared with the controls (OR = 7.0, P= 0.038 and OR = 21.64, P= 0.009, respectively), but the significance of the difference did not resist Bonferroni correction. Haplotype analysis showed that DRB1*0402 was always present with DQB1*0302 and DRB1*1401 with DQB1*0503, but no independent effect of the DQB1*0302 in the former haplotype was evident. Our results support the hypothesis that the DRB1*0402 without DQB1*0302 is the most relevant HLA-DRB1 allele responsible for the pathogenesis of pemphigus in Venezuelan patients with PV and discard the DQB1*0302 influence observed in other populations.

Epidemiologic survey of pemphigus vulgaris with oral manifestations in northern Greece: retrospective study of 129 patients

OBJECTIVE

To evaluate the epidemiology of pemphigus vulgaris (PV) in a Greek population and to compare it with other countries.

MATERIALS AND METHODS

A retrospective study was conducted based on the records of 129 patients (41 males and 88 females) with PV who visited the Department of the Oral Medicine and Maxillofacial Pathology, Aristotle University of Thessaloniki, Greece and the State Hospital for Skin and Venereal Diseases of Thessaloniki, Greece, between 1985 and 2004. A group of 73 individuals was used as controls.

RESULTS

The average annual incidence was found to be eight patients per year. The male to female ratio was 1 : 2.25. The difference in the age of onset between the two genders was statistically significant in marginal levels (P = 0.05). In addition, 86.1% of the patients showed oral lesions only, 13.3% oral and skin lesions and 1.3% manifested oral, skin, and ocular lesions. Twenty-eight of the 88 females were in the premenopausal period-of-life. Additionally, 19 males were farmers who had daily contact with organophosphoric pesticides. Co-existing pathologic conditions were present in 75 of the 129 patients, and of these 75 patients six (8%) were diabetics, 15 (20%) presented with hypertension, two (2.6%) faced problems from their thyroid gland, and 10 (13.3%) of the patients complained of allergic reactions.

CONCLUSIONS

The results of this study demonstrated a relatively high incidence of PV in northern Greece compared with that in other countries. The disease most frequently occurred in the sixth decade-of-life and the majority of the patients manifested oral lesions. Further epidemiological studies are needed to elucidate whether this region is constituted from population groups with high susceptibility to PV.

Disease relevant HLA class II alleles isolated by genotypic, haplotypic, and sequence analysis in North American Caucasians with pemphigus vulgaris

Early studies of genetic susceptibility to pemphigus vulgaris (PV) showed associations between human leukocyte antigen (HLA) DR4 and DR6 and disease. The emergence of DNA sequencing techniques has implicated numerous DRB1 and DQB1 loci in various populations, leading to confusion regarding which exact alleles confer susceptibility. The strong linkage disequilibrium among DR and DQ HLA alleles further complicates the investigation of the true susceptibility loci. In this study, we report genotyping data for the largest sampling of North American Caucasian non-Jewish and Ashkenazi Jewish PV patients studied to date and compare our data with other population studies. To pinpoint true susceptibility, alleles among overrepresented sequences, we applied a step-wise reductionist analysis through (1) determination of the degree of linkage disequilibrium (LD) between purportedly associated alleles, (2) haplotype frequencies comparisons, and (3) primary sequence comparisons of disease-associated versus non-disease-associated alleles to identify crucial differences in amino acid residues in putative peptide binding pockets. Collectively, our data provide extended support for the hypothesis that the HLA associations in Caucasian PV patients map to DRB1*0402 and DQB1*0503 alone. Further structure-function studies will be required to define the exact mechanisms of HLA-mediated control of susceptibility and resistance to disease.

Genetic factors in pemphigus

Epidemiological studies performed in different ethnic populations and family studies, notably based on a partial phenotype of the autoimmune process, indicate that genetic factors are involved in the occurrence of pemphigus. However, the precise heritability remains uncertain in the absence of twin concordance rate studies. Among the different strategies available to identify genetic factors participating in autoimmune disease susceptibility, only population studies based on case-control design have been performed in pemphigus. These studies consistently showed that MHC locus, in particular HLA class II alleles, are associated with pemphigus vulgaris and pemphigus foliaceus. Other genes of the MHC locus may also participate in disease susceptibility as shown by studies using microsatellite markers across different regions of the MHC. It is likely that other non-MHC genes are involved in the pathogenesis of pemphigus. In particular, involvement of a polymorphic variant of desmoglein 1 gene was shown to be associated with pemphigus foliaceus and to interact in an epistatic manner with MHC class II genes to contribute to the autoimmune process. Other candidate genes to which a role can be assigned in the disease pathogenesis should be considered to design case-control or family-based association studies. Genome scan studies which require a large number of multiplex families to reach statistical power, should also be considered in the endemic form of pemphigus foliaceus because of the high number of familial cases.

Number II Pemphigus vulgaris

Pemphigus is a group of potentially life-threatening autoimmune diseases characterized by cutaneous and/or mucosal blistering. Pemphigus vulgaris (PV), the most common variant, is characterized by circulating IgG antibodies directed against desmoglein 3 (Dsg3), with about half the patients also having Dsg1 autoantibodies. There is a fairly strong genetic background to pemphigus with linkage to HLA class II alleles and ethnic groups such as Ashkenazi Jews and those of Mediterranean and Indian origin, are especially liable. Oral lesions are initially vesiculobullous but readily rupture, new bullae developing as the older ones rupture and ulcerate. Biopsy of perilesional tissue, with histological and immunostaining examination are essential to the diagnosis. Serum autoantibodies to either Dsg1 or Dsg3 are best detected using both normal human skin and monkey oesophagus or by enzyme-linked immunosorbent assay. Before the introduction of corticosteroids, PV was typically fatal mainly from dehydration or secondary systemic infections. Current treatment is largely based on systemic immunosuppression using corticosteroids, with azathioprine or other adjuvants or alternatives but newer therapies with potentially fewer adverse effects, also appear promising.

Higher prevalence of human herpesvirus 8 DNA sequence and specific IgG antibodies in patients with pemphigus in China

BACKGROUND

Environmental factors, including virus infection, may play a role in the onset and/or development of pemphigus. However, it is controversial whether human herpesvirus (HHV)-8 is involved in pathogenesis of pemphigus.

OBJECTIVE

The possible association of pemphigus with HHV-8 was investigated.

METHODS

A total of 36 lesional skin and 13 peripheral blood mononuclear cell specimens from 58 patients with pemphigus, and 18 normal skin and 230 peripheral blood mononuclear cell specimens from healthy individuals, were tested for HHV-8 DNA sequence by a nested polymerase chain reaction assay. In all, 29 sera from the patients and 109 sera from healthy individuals were tested for HHV-8-specific IgG antibodies by enzyme-linked immunosorbent assays using HHV-8-specific oligopeptides as antigens.

RESULTS

Prevalence of both HHV-8 DNA sequence (36.1% and 30.8% in lesional skin and in peripheral blood mononuclear cells, respectively) and HHV-8-specific IgG antibodies (34.5%) for patients with pemphigus was statistically higher than that of control subjects (<8% in both assays). There was no significant difference in HHV-8 prevalence among different types of pemphigus.

CONCLUSION

HHV-8 infection might be a contributing factor in the development of pemphigus.

Pemphigus vulgaris: update on etiopathogenesis, oral manifestations, and management

Pemphigus is a group of potentially life-threatening diseases characterized by cutaneous and mucosal blistering. There is a fairly strong genetic background to pemphigus with linkage to HLA class II alleles. Certain ethnic groups, such as Ashkenazi Jews and those of Mediterranean origin, are especially liable to pemphigus. Pemphigus vulgaris (PV), the most common and important variant, is an autoimmune blistering disease characterized by circulating pathogenic IgG antibodies against desmoglein 3 (Dsg3), about half the patients also having Dsg1 autoantibodies. Oral lesions are initially vesiculobullous but readily rupture, new bullae developing as the older ones rupture and ulcerate. Biopsy of perilesional tissue, with histological and immunostaining examinations, is essential to the diagnosis. Serum autoantibodies to either Dsg1 or Dsg3 are best detected by both normal human skin and monkey esophagus or by enzyme-linked immunosorbent assay (ELISA). Before the introduction of corticosteroids, pemphigus vulgaris was typically fatal mainly from dehydration or secondary systemic infections. Current treatment is largely based on systemic immunosuppression using systemic corticosteroids, with azathioprine, dapsone, methotrexate, cyclophosphamide, and gold as adjuvants or alternatives, but mycophenolate mofetil and intravenous immunoglobulins also appear promising.

Pemphigus vulgaris with oral involvement: evaluation of two different systemic corticosteroid therapeutic protocols

BACKGROUND

Pemphigus vulgaris is a potentially life-threatening disease characterized by cutaneous and mucosal blistering. Systemic corticosteroids remain the mainstay of therapy, transforming an invariably fatal disease into one with a mortality that is now less than 10%. Nevertheless, oral lesions are often recalcitrant and corticosteroid therapy can provoke adverse effects.

OBJECTIVE

To determine whether two different regimens of systemic corticosteroid therapy based on prednisone gave different benefits.

METHOD

We examined two different regimens of systemic corticosteroid therapy based on prednisone in an open study. Ten patients (group A) were treated with systemic corticosteroids, in a therapeutic protocol made up of orally administered prednisone. Ten matched patients (group B) were treated with systemic corticosteroids alternating a pulse of intravenous betamethasone with orally administered prednisone.

RESULTS AND CONCLUSIONS

The pulse protocol appeared to have some advantages both in a shorter time to resolution of symptoms and oral lesions, and in terms of minor adverse effects.

A study of desmoglein 1 autoantibodies in pemphigus vulgaris: racial differences in frequency and the association with a more severe phenotype

BACKGROUND

Pemphigus vulgaris (PV) is characterized by pathogenic autoantibodies to desmoglein (Dsg) 3, but additional antibodies to Dsg1, the pemphigus foliaceus antigen, are detectable in some cases.

OBJECTIVES

To investigate the clinical significance of the presence of both Dsg 1 and 3 antibodies.

METHODS

In 79 subjects with PV, enzyme-linked immunosorbent assays were used to detect IgG autoantibodies reactive with the ectodomain of Dsg1 and Dsg3.

RESULTS

There was a clear association between the clinical phenotype and the Dsg antibody profile. All subjects had Dsg3 autoantibodies and 61% had coexisting Dsg1 antibodies (Dsg3+/Dsg1+). PV limited entirely to the mucosal surfaces was seen only in Dsg3+/Dsg1- patients, while additional Dsg1 antibodies (Dsg3+/Dsg1+) predicted cutaneous in addition to mucosal involvement. Although minor cutaneous involvement was observed in most Dsg3+/Dsg1- patients, severe cutaneous involvement was seen only in Dsg3+/Dsg1+ patients. Dsg1 antibodies were detectable early in the course of disease and their appearance did not relate to the use of systemic therapy. The proportion of Dsg1+ patients was higher in those of Indian origin compared with white northern Europeans (P < 0.05).

CONCLUSIONS

These data suggest that the presence of Dsg1 antibodies is predictive of a potentially more severe disease and that genetic factors may determine the Dsg antibody profile.

HLA class II polymorphism contributes to specify desmoglein derived peptides in pemphigus vulgaris and pemphigus foliaceus

Susceptibility to Pemphigus, an autoimmune disease of the skin, has been previously linked to DRB1*0402, 1401/04 and DQB1*0503 in pemphigus vulgaris (PV), to DRB1*0102, 0404, 1402/06 in endemic pemphigus foliaceus in Brazil and to DRB1*04 in Italian patients suffering from pemphigus foliaceus (PF). The disease is caused by autoantibodies against desmoglein (Dsg1 in PF, Dsg3 in PV). Molecular typing of 57 French patients suffering from PV (37) and from PF (20) confirmed previous results concerning PV and showed that DRB1*0102 and 0404 are susceptible molecules to PF in France. We have analysed the characteristics of the 'pockets' of the susceptibility-associated molecules to PV and PF and we showed that (i) in PV, two kinds of Dsg3 derived peptides may be presented by HLA-DR according to HLA polymorphism (DRB1*0402 or DRB1*14/0406), (ii) the same Dsg1 peptides may be presented by DRB1*0102, DQB1*0404 or DRB1*14 in PF, (iii) the DRB1*14/0406 PV-related molecules may be able to present Dsg1 and Dsg3 peptides thereby providing an explanation for the cases of PV with combined responses to Dsg1 and to Dsg3 which are typified by a muco-cutaneous clinical phenotype.

Detection of herpesvirus DNA in peripheral blood mononuclear cells and skin lesions of patients with pemphigus by polymerase chain reaction

Pemphigus is an autoimmune disease where both endogenous (genetic) and exogenous (environmental) factors play a part. Viral infections, in particular herpesvirus infections, have been identified as a possible triggering factor for pemphigus. In this study, using the polymerase chain reaction, we studied peripheral blood mononuclear cells (PBMC) and skin biopsies from patients with pemphigus, and in some of these were able to demonstrate the presence of DNA sequences of herpes simplex virus 1/2 (50% in PBMC and 71% in skin biopsies), Epstein-Barr virus (15% in PBMC and 5% in skin biopsies) and human herpesvirus 6 (20% in PBMC only). However, the inability to detect herpesvirus DNA consistently in these cases suggests that viral infection may only be an occasional factor triggering the outbreak or exacerbation of the disease. The possible role of interferons and interleukins in the pathogenesis of virus-induced pemphigus is discussed.

Common human leukocyte antigen alleles in pemphigus vulgaris and pemphigus foliaceus Italian patients

Pemphigus refers to a group of autoimmune blistering skin diseases, mainly identified as pemphigus vulgaris and pemphigus foliaceus, both characterized by the presence of autoantibodies against keratinocyte adhesion molecules, leading to loss of cell-cell adhesion with consequent blister formation. Pemphigus vulgaris is reported to be associated with human leukocyte antigen DR4 and/or DR6 whereas no data are available on pemphigus foliaceus, except for the endemic Brazilian form (fogo selvagem), which is reported to be associated with DR1 and DR4. We here report human leukocyte antigen molecular typing on a total of 87 patients, 61 with pemphigus vulgaris and 26 with pemphigus foliaceus, versus 128 healthy matched controls. Generic typing showed an increase of DRB1*04 and DRB1*14 and a decrease of DRB1*07 in both pemphigus vulgaris and pemphigus foliaceus patients. Molecular subtyping of DR4+ and DR14+ subjects showed a highly significant association between the DRB1*1401 and both pemphigus vulgaris (p < 0.0001) and pemphigus foliaceus patients (p < 0.0001) together with a significant increase of the linked DQB1*0503 (pemphigus vulgaris p < 0.0001; pemphigus foliaceus p < 0.0001). Moreover, whereas the association between DRB1*0402 and pemphigus vulgaris (p < 0.0001) has been confirmed, no significant association between a specific allele of the DR4 group and pemphigus foliaceus, has been found. Therefore, at least in Italian patients, pemphigus vulgaris and pemphigus foliaceus share DRB1*1401 and DQB1*0503, as susceptible human leukocyte antigen alleles, whereas DRB1*0402 is only found associated with pemphigus vulgaris. The observation that both diseases, pemphigus vulgaris and pemphigus foliaceus, carry the same susceptible human leukocyte antigen alleles has been interpreted as a common genetic background predisposing to pemphigus as, like in other autoimmune disorders, it is not sufficient to explain the onset of the disease on the basis of the sole aforementioned alleles. Other linked genes and/or environmental factors should play a facilitating role in the outbreak of pemphigus, either pemphigus vulgaris or pemphigus foliaceus.

Pemphigus vulgaris: the manifestations and long-term management of 55 patients with oral lesions

Perhaps surprisingly, the manifestations and management of patients with pemphigus vulgaris and oral lesions have been detailed only infrequently. The present study has examined the clinical features, diagnosis and management of a cohort of 55 patients, including three adolescents, with pemphigus vulgaris predominantly affecting the oral mucosa. There was about a 6-month delay from the onset of symptoms until presentation for diagnosis, longer in men than in women. Patients typically had multiple lesions affecting mainly the buccal and/or palatal mucosae, and over half the patients had lesions affecting non-oral mucosal sites. Nearly one-quarter (24%) had cutaneous involvement. Most patients were otherwise healthy with no other autoimmune disorders. Classical histopathological features of pemphigus vulgaris were present in all patients, as well as IgG intraepithelial deposits in all patients tested and circulating epithelial antibodies in most. Thirty-two patients were treated in the clinic, four responding to topical immunosuppressive therapy, the remainder needing and responding, at least in part, to systemic immunosuppression. Systemic corticosteroids often with adjunctive immunosuppressives, particularly azathioprine, were required in 87% of patients. In 18% of the patients, the disease resolved in 3 months, but 76% had recalcitrant disease. Adverse effects were seen in 78%, and two patients died, at least one as a consequence of immunosuppressive therapy. It is concluded that pemphigus vulgaris affecting the oral mucosa is still diagnosed only after considerable delay because patients, especially men, present late; it has a chronic course; it is often associated with lesions in other mucosae and/or skin; it can be resistant to currently available therapies; and immunosuppressive therapy frequently produces adverse effects, occasionally lethal.

Distribution of HLA class II alleles among Spanish patients with pemphigus vulgaris

Twenty-six unrelated Spanish Caucasian individuals affected by pemphigus vulgaris (PV) were HLA typed and frequencies compared with those of 200 ethnically matched healthy controls. Twenty-three out of 26 patients were HLA-DR4. The frequency of HLA-DR14 was also increased (31%; controls: 4%). Of the 23 patients positive for HLA-DR4, 21 carried the DRB1*0402 allele. Therefore, the frequency of HLA-DRB1*0402 among patients was 81% (4% in controls; P=4.7x10(-27), OR=100.8). Interestingly, HLA-DR13, a frequent HLA-DR specificity in the Spanish general population (27%), was absent among the PV patients (P=0.009; Pc=0.1; OR=0.05). Taking together these data, we can conclude that, in the Spanish population, PV is preferentially and strongly associated with HLA-DRB1*0402, whereas DRB1*13 seems to confer a protective effect in our population.

Polymorphisms of HLA class II genes in Japanese patients with pemphigus vulgaris

Pemphigus vulgaris (PV) is an autoimmune disease mediated by autoantibodies that bind to a keratinocyte adhesion molecule, desmoglein-3. The purpose of this study was to identify critical amino acid residues of PV-associated HLA class II genes. Haplotype and allele distributions, along with molecular polymorphisms, of HLA class II genes were analyzed based on the polymerase chain reaction-restriction fragment length polymorphism in 17 Japanese PV patients. Each patient had one or two alleles of DRB1*04 (*0403, *0404, *0406) or DRB1*14 (*1401, *1405, *1406) subtypes. All DRB1*04 and DRB1*14 alleles carried by PV patients with different ethnic backgrounds reported to date, including DRB1*0402, which confers strong susceptibility to PV among Jewish populations, have amino acid residues Phe26, Leu67 or Ile67, and Val86, as well as hydrophilic amino acid residues at positions 70 and 71 of the DRB1 beta chain.

Pemphigus vulgaris autoantibody response is linked to HLA-DQB1*0503 in Pakistani patients

Pemphigus vulgaris (PV) is an autoimmune disease of the skin and mucous membranes characterized by an autoantibody response against an epidermal cadherin. We performed high resolution HLA class II typing in 19 patients with PV from Rawalpindi, Pakistan and 19 non-Jewish European PV patients from Boston by sequence-specific oligonucleotide probe hybridization. The results were compared with two separate ethnically matched control populations. WE found that PV patients from Pakistan had significantly increased frequencies of DRB1*1404 (p = 0.01), DQA1*0101 (p = 0.02), and DQB1*0503 (p = 0.01). Among the patients of non-Jewish European ancestry, DRB1*1401 (p < 10(-6)), DQA1*0101 (p < 10(-5)) and DQB1*0503 (p < 10(-6)), were increased in PV patients. Formal linkage analysis between the major histocompatibility complex and the PV antibody was performed in 67 relatives of the 19 Pakistani patients. The results showed strong evidence for linkage of HLA-DRB1*1404, DQA1*0101, DQB1*0503, with the presence of PV antibody in relatives' families with a significant logarithm of the odds score of 6.06. Based on the three dimensional structure of class II molecules, we propose that HLA-DQA1*0101 and DQB1*0503, encode a negatively charged P9 peptide binding pocket of the DQ molecule and are significantly associated with susceptibility to PV in non-Jewish populations.

Identical MHC markers in non-Jewish Iranian and Ashkenazi Jewish patients with pemphigus vulgaris: possible common central Asian ancestral origin

Previous studies showed that almost all Ashkenazi Jewish patients with pemphigus vulgaris carried the extended haplotype [HLA-B38, SC21, DRB1*0402, DQB1*0302] or [HLA-B35, SC31, DRB1*0402, DQB1*0302] or class II fragments of them. Non-Jewish patients carried [HLA-B55, SB45, DRB1*1401, DQB1*0503] or its class II fragments. In the present study of 20 Iranian patients with pemphigus vulgaris, 17 were found to carry DRB1*0402, DQB1*0302 haplotypes, also found among normal Iranian haplotypes and the same as that of the Jews. These findings suggest that the pemphigus MHC susceptibility gene among Iranians derived from the same ancestor as that in the Ashkenazim. The ancient Jews were under Persian domination from 500 B.C. until 300 B.C. and in the 8th century A.D., a Tataric people living in the kingdom of Khazar on the Western shore of the Caspian Sea and the Northern shore of the Black Sea, near Persia, converted to Judaism, providing possible opportunities for gene mixing in two populations that are distinct and separate today.

Development and characterization of desmoglein-3 specific T cells from patients with pemphigus vulgaris

Pemphigus vulgaris (PV) is a cutaneous autoimmune disease characterized by blister formation in the suprabasilar layers of skin and mucosae and anti-desmoglein-3 (Dsg3) autoantibodies bound to the surface of lesional keratinocytes and circulating in the serum of patients. This disease can be reproduced in neonatal mice by passive transfer of patients' IgG, indicating that humoral immunity plays an important role in the pathogenesis of PV. Currently, the role of T lymphocytes in the development of PV is not clear. Here, we report that three immunoreactive segments of the ectodomain of Dsg3 specifically induced proliferation of T cells from PV patients. We found that T lymphocytes from 13 out of 14 patients responded to at least one of three Dsg3 peptides. T cells from controls and other patient groups did not respond to these Dsg3 peptides. The major T cell population stimulated by these Dsg3 peptides was CD4 positive. Dsg3-specific T cell lines and clones were developed and were shown to express a CD4 positive memory T cell phenotype. Upon stimulation, these cell lines and clones secreted a Th2-like cytokine profile. The Dsg3 responses of these T cells were restricted to HLA-DR, and not -DQ and -DP, of the major histocompatibility complex. This information will help to elucidate the cellular immune abnormalities leading to production of pathogenic IgG autoantibodies in patients with PV.

MHC class II alleles and haplotypes in patients with pemphigus vulgaris from India

Pemphigus vulgaris (PV) is a blistering disease of the skin and mucous membranes characterized by an autoantibody response against a keratinocyte adhesion molecule, desmoglein 3, causing acantholysis and blister formation. We compared high resolution MHC class II alleles and haplotype frequencies (HLA-DRB, DQA1 and DQB1) in 37 patients with PV to 89 haplotypes of normal relatives from New Delhi and Ahmedabad. We found that PV patients had significantly increased frequencies of DRB1*1404 (P < 0.0001), DQA1*0101 (P = 0.001), and DQB1*0503 (P < 0.0001). These associations were due to the increased frequencies of the haplotype HLA-DRB1*1404, DRB3*0202, DQA1*0101, DQB1*0503 in patients compared to control haplotypes (p < 0.0001). Also, patients from Ahmedabad had a significant increase in HLA-DQB1*0302 (p = 0.03). An identical amino acid sequence (Leu-Leu-Glu-Arg-Arg-Arg-Ala-Glu), in positions 67-74 of the beta domain of DRB alleles is restricted to some DR14 alleles. Therefore, there are three possible explanations for class II allele involvement in autoantibody in PV patients with class II haplotypes marked by HLA-DR14. First, the class II alleles could be markers for an unidentified susceptibility gene in linkage disequilibrium with them. Second, the primary association could be with DQB1*0503 and the association with HLA-DR14 alleles would be the result of linkage disequilibrium. Third, the HLA-DRB1 locus susceptibility could involve a specific amino acid sequence in the third hypervariable region shared by several HLA-DR14 alleles.