Serum and salivary IgG and IgA antibodies to desmoglein 3 in mucosal pemphigus vulgaris.

BACKGROUND: The use of saliva for the diagnosis of pemphigus vulgaris (PV) by enzyme-linked immunosorbent assay (ELISA) using desmoglein (Dsg)3 antigen has not been extensively documented, nor has the detection of serum IgA antibodies to Dsg3. OBJECTIVES: (i) To establish whether whole saliva might provide a suitable alternative to serum for diagnosing and monitoring PV; (ii) to investigate whether anti-Dsg3 IgA antibodies can be detected in serum and saliva and (iii) to establish whether there is an association between serum or saliva anti-Dsg3 antibodies and disease severity. METHODS: Precoated Dsg3 ELISA plates were used to test serum and/or saliva for IgG and IgA antibodies. Matched serum and whole saliva samples were collected from 23 patients with PV, 17 healthy subjects and 19 disease controls. All patients with PV, disease controls and six healthy controls provided matched parotid saliva. RESULTS: Whole saliva IgG antibodies to Dsg3 were detected in 14 of 23 patients (61%) and serum IgG antibodies were detected in 17 of 23 (74%) with a strong positive correlation. Serum IgA antibodies were detected in 14 of 23 patients with PV (61%) with a combined positivity (IgG and/or IgA antibodies to Dsg3) of 78% (18 of 23). We were unable to show IgA anti-Dsg3 antibodies in either whole or parotid saliva of patients with PV. Sequential samples showed that changes in IgG antibody titres in whole saliva were associated with a change in disease severity scores. CONCLUSIONS: Assay of salivary IgG antibodies to Dsg3 offers a diagnostic alternative to serum in the diagnosis and monitoring of PV. The role of anti-Dsg3 IgA antibodies requires further elucidation in the pathogenesis of PV.

Immunopathological characteristics of patients with bullous pemphigoid and neurological disease.

BACKGROUND: The relationship between bullous pemphigoid (BP) and neurological disease has been the subject of numerous recent studies and BP antigens and their isoforms have been identified in the central nervous system (CNS). Whilst epidemiological data support this association, little is known about the pathomechanism behind this link and the immunological characteristics of patients with BP and neurological disease, other than multiple sclerosis (MS), has not been studied. OBJECTIVE: We aimed to compare the cutaneous immune response in BP patients with and without neurological disease, to investigate whether or not there is a distinctive immunopathological profile in patients with concomitant BP and neurological disease. METHODS: Seventy-two patients with BP were included and divided into two groups; those with neurological disease (BP+N, n = 43) and those without (BP-N, n = 29). Patients in BP+N group had a confirmed neurological disease by a hospital physician, neurologist or psychiatrist with positive neurological imaging where appropriate, or a Karnofsky score of 50 or less due to mental impairment. All sera were analysed with indirect immunofluorescence (IIF) using serial dilutions up to 1:120000, immunoblotting (IB) and Enzyme-linked immunosorbent assay (ELISA) for BP180 and BP230. RESULTS: Median antibody titres by IIF were 1:1600 vs. 1:800 for BP-N and BP+N, respectively, although the difference did not reach statistic significance (P = 0.93, Mann-Whitney U-test). ELISA values for both BP180 and BP230 did not differ significantly between the two groups. Similarly, autoantibodies to specific antigens as identified by ELISA and IB were not related to the presence of neurological disease. CONCLUSION: The results of this study indicate that patients with BP and neurological disease exhibit an immune response to both BP180 and BP230, thus the link between the CNS and the skin is not dependent on a specific antigen, but possibly both antigens or their isoforms may be exposed following a neurological insult, and play a role in generation of an immune response.

Prognostic factors in pemphigus vulgaris and pemphigus foliaceus.

BACKGROUND: Pemphigus typically has a chronic course, although there is great variability in disease duration (DD) and time taken to disease remission (DR) between individuals with the disease. The reasons for this are unclear. OBJECTIVES: To explore the prognostic influence of epidemiological, clinical, immunological and genetic factors on disease course and remission in pemphigus vulgaris (PV) and pemphigus foliaceus (PF). METHODS: This was a retrospective study of patients with PV and PF, recruited from a single UK centre. Direct and indirect immunofluorescence and enzyme-linked immunosorbent assay studies for antidesmoglein (Dsg) antibodies were used to assess immunological factors. Polymerase chain reaction with sequence specific primers (PCR-SSP) was used to assess the Class II human leukocyte antigen status of patients. Prognostic endpoints investigated were time to initial first DR and total DD. RESULTS: Ninety-five patients were recruited (79 PV and 16 PF). Patients of Indo-Asian origin were significantly associated with longer DD than White-British patients (P = 0.029). In addition, younger age at onset was associated with a worse prognosis in terms of DD: the mean age at presentation of patients with DD of < 5 years was 49 years (SEM = 3.4) compared with 40 years (SEM = 1.9) in those with DD > 5 years (P = 0.039). A higher initial intercellular antibody titre on normal human skin substrate was associated with a greater time to initial DR (P = 0.007) and high anti-Dsg 3 levels at baseline were associated with a longer total DD (P = 0.03). CONCLUSIONS: Ethnic group, age at presentation, initial intercellular antibody titre and initial Dsg 3 antibody levels all had a significant impact on prognosis of pemphigus.

Immunobullous dermatosis associated with Waldenström macroglobulinaemia treated with rituximab.

Waldenström macroglobulinaemia (WM) is a chronic lymphoproliferative disorder characterized by the presence of a monoclonal IgM paraprotein. Specific cutaneous features of WM include neoplastic cell infiltrates, IgM storage papules and IgM bullous dermatosis. We report a patient with subepidermal bullous disease associated with WM. Immunofluorescence identified IgM deposition along the basement membrane zone (BMZ) with circulating anti-BMZ IgM antibodies reacting with the dermal side of salt-split skin. The autoantibodies did not react with type VII collagen or laminin 332. Following failed treatment with doxycycline, prednisolone, intravenous immunoglobulin and dapsone, the patient was successfully treated with a modified RCVP regimen (rituximab, cyclophosphamide and prednisolone). To our knowledge, this is the first reported case of IgM bullous disease of WM treated with rituximab.

Antigen identification using skin deficient in basement-membrane protein: a novel tool for the diagnosis of subepidermal immunobullous diseases.

Common unifying features of the subepidermal blistering diseases are the presence of tense blisters clinically and demonstration by immunofluorescence of linear deposition of immunoreactants along the dermoepidermal junction. Further characterization of subtype is possible by identification of the target antigen by immunoblotting. However, immunoblotting is time-consuming and may not be practical for routine use in the laboratory. In this report, we describe a simple technique to identify the target antigen by indirect immunofluorescence, using epidermolysis bullosa skin as substrate.

Bullous pemphigoid in a patient with suspected non-Herlitz junctional epidermolysis bullosa.

A 56-year-old man with lifelong trauma-induced blisters, nail dystrophy and dental enamel hypoplasia presented with a new spontaneous blistering eruption. Clinicopathologically, he had evidence of both an inherited and an acquired blistering disorder: non-Herlitz junctional epidermolysis bullosa (nHJEB) and bullous pemphigoid (BP). HIstological examination of a skin biopsy found reduced (but not absent) collagen XVII in nonlesional skin, in vivo bound anticollagen XVII antibodies in perilesional skin, and prominent eosinophils in perilesional and lesional skin, with subepidermal blistering. Circulating anticollagen XVII antibodies were also present. Treatment with oral corticosteroids and mycophenolate mofetil led to clinical control of the BP but had no effect on the mechanobullous blistering. Our patient is unusual in that his skin retains some labelling for collagen XVII rather than having the complete absence of immunoreactivity expected in patients with generalized nHJEB. Moreover, we were unable to identify any pathogenic mutations in the COL17A1 gene encoding collagen XVII (or in other EB-associated basement membrane genes). It is plausible that the long-term consequences of basement membrane disruption in our patient, perhaps associated with atypical inherited COL17A1 pathology, might result in a conformationally altered and more immunogenic protein with the subsequent development of anticollagen XVII antibodies and BP as a secondary pathology.

Childhood vulval lichen sclerosus: autoimmunity to the basement membrane zone protein BP180 and its relationship to autoimmunity.

Lichen sclerosus (LS) is associated with autoimmune disease in female children and adults. In adult women, there are antibody and T-cell responses to proteins in the basement membrane zone (BMZ). The aim of this study was to investigate reactivity to the BMZ in girls with LS. Nine girls with vulval LS were studied clinically and serologically. The presence of circulating BMZ autoantibodies was investigated. Autoimmunity was assessed by personal and family history of autoimmune diseases and autoantibodies. We detected circulating BMZ antibodies in four of the nine children, all with IgG responses. Three patients were positive by indirect immunofluorescence, one had a positive ELISA reaction to bullous pemphigoid antigen (BP)180, and three had a positive reaction on BP180 immunoblots. There was no association with autoimmune disease or clinical features. To our knowledge, this is the first study to find BMZ autoantibodies in children with vulval LS. The autoantibodies were directed at BP180 and were exclusively of the IgG class.

Pulsed intravenous cyclophosphamide and methylprednisolone therapy in refractory pemphigus.

BACKGROUND: Pemphigus is a rare autoimmune blistering disorder. The mainstay of current treatment is high-dose oral corticosteroid therapy in combination with a steroid-sparing agent. Adjuvant therapy is important for disease control and to reduce the iatrogenic effects of oral prednisolone. Pulsed therapy with intravenous methylprednisolone and cyclophosphamide (PPC) has been shown to be an effective treatment but there are currently few data on its use in patients who have failed to respond to conventional immunosuppression. OBJECTIVES: To report the clinical and immunological responses of 21 patients with pemphigus refractory to prednisolone and azathioprine or mycophenolate mofetil treated in our department with a standard protocol of monthly PPC. METHODS: Patients with pemphigus were identified who had undergone PPC therapy during the period between 1997 and 2006. Initial clinical severity and response to treatment was assessed. In addition, change in intercellular antibody titres and desmoglein 1 and 3 antibodies to PPC therapy was also recorded. RESULTS: Of the 21 patients treated, seven had an excellent response, two a good response, five a moderate response, six a minimal response and one patient had no clinical response. Four patients achieved complete clinical remission and the number of pulses for these patients varied between 11 and 22. We observed significant reductions in indirect immunofluorescence titres for normal human skin substrate (P = 0.0078) and antidesmoglein 1 and 3 autoantibody levels (P = 0.007 and P = 0.0085, respectively) from pre-PPC therapy to 1 year after the last pulse. All patients were able to reduce their prednisolone dose from a pre-pulsing median dose of 40-10 mg at the last pulse with a median dose reduction of 66% (P < 0.001). The most common adverse effect was transient lymphopenia (12 patients); nonlife-threatening sepsis (seven patients) and premature ovarian failure (two patients) also occurred. CONCLUSIONS: PPC can be an effective treatment for refractory pemphigus but its adverse effects should be considered prior to therapy and closely monitored in patients on treatment.

T cells reactive with the NC16A domain of BP180 are present in vulval lichen sclerosus and lichen planus.

BACKGROUND: Lichen sclerosus (LS) is a chronic inflammatory skin condition. The recent demonstration of circulating autoantibodies to extracellular matrix protein 1 and to basement membrane zone (BMZ) components, chiefly BP180, suggests that autoimmunity to these components might contribute to pathogenesis. However, there is no binding of autoantibodies in vivo and as LS is characterized by a lymphocytic infiltrate, it seems likely that LS is mediated, in part, by antigen-specific lymphocytes. Similar mechanisms may apply to vulval lichen planus (LP), an interface dermatitis, with clinical and immunological overlap with LS. OBJECTIVES: This study aims to test the hypothesis that T cells reactive with the NC16A domain of BP180 are present in the peripheral blood of patients with vulval LS and LP. METHODS: Isolated peripheral blood mononuclear cells from 14 patients with vulval LS, 5 with vulval LP and 4 healthy controls were grown in vitro. We examined for immunogenicity of overlapping peptides spanning the NC16A domain of BP180 using interferon-gamma enzyme-linked immunospot assay (ELIspot) on the cultured T-cell lines. BMZ antibodies were assayed, HLA type determined and clinical parameters noted. RESULTS: Significant interferon-gamma production was observed in response to the NC16A peptides in 6 of the 14 vulval LS and 2 of the 5 LP patients, but not in the control subjects. There was an associated autoantibody response to BP180 in 3 LS and 1 LP patient with T-cell responses. These data suggest that in some vulval LS and LP patients, NC16A domain-specific T cells circulate at sufficiently high frequency to be detectable in vitro and show rapid effector function. There was no association with HLA type or clinical parameters. CONCLUSION: We have demonstrated that in > 40% of our vulval LS and LP patients, the NC16A domain of BP180 is a target for circulating T cells, and in vulval LS and LP there are associated autoantibodies to BP180.

Inflammatory epidermolysis bullosa acquisita mimicking toxic epidermal necrolysis and dermatitis herpetiformis.

We report a patient with a spectrum of clinical features simulating toxic epidermal necrolysis, bullous erythema multiforme and later, dermatitis herpetiformis (DH). The histological features were suggestive of DH, bullous pemphigoid (BP) and epidermolysis bullosa acquisita (EBA). Direct immunofluorescence results suggested BP or EBA. Indirect immunofluorescence on salt-split skin and immunoblotting analysis on normal human dermal extracts gave results that were diagnostic for EBA.

Bullous pemphigoid in an infant using complementary medicine.

Bullous pemphigoid (BP) is an acquired immunobullous disorder rarely seen in childhood. We report the case of an infant with BP successfully treated with oral corticosteroids. The onset of BP was associated with use of complementary medications and we speculate that these may have been triggering factors.

Localized bullous pemphigoid in a patient with primary lymphoedema tarda.

We report a case of localized bullous pemphigoid (BP) in a woman patient with primary lymphoedema tarda. There is only one previous case reported of localized pemphigoid in an area of lymphoedema, this being of the cicatricial variant. Slow circulation in the lymphatic vessels, increased capillary permeability with preferential localization of antibodies in the area, and potential cleavage of the epidermal junction due to increased hydrostatic pressure leading to autoimmunity, have all been advocated as possible pathogenic mechanisms. Nevertheless, we consider that the mechanism by which localized pemphigoid arises on lymphoedema remains elusive, based on a previous case of generalized BP sparing an area of postsurgical lymphoedema.

Bullous pemphigoid antigen II (BP180) and its soluble extracellular domains are major autoantigens in mucous membrane pemphigoid: the pathogenic relevance to HLA class II alleles and disease severity.

BACKGROUND: Mucous membrane pemphigoid (MMP), a chronic autoimmune subepithelial blistering disease, is associated with circulating IgG and/or IgA autoantibodies against several basement membrane zone antigens. The heterogeneity of clinical presentation and diversity of target autoantigens have contributed to difficulties in characterizing this condition immunologically. OBJECTIVES: To analyse serum autoantibody profile and HLA class II alleles in MMP patients and to correlate this with the clinical presentation of disease. METHODS: Well-defined subgroups consisting of 124 patients with MMP were examined for IgG and IgA reactivity with immunoblotting using human epidermal, dermal and placental amnion proteins. The results were further analysed on the basis of detailed clinical (sites of involvement and disease severity) and immunopathological criteria (immunofluorescence study and HLA class II alleles). RESULTS: Immunoblot assay revealed that the majority of MMP patients had IgG (93 of 124, 75%) and/or IgA autoantibodies (63 of 124, 51%) to BP180 (including its soluble ectodomains, 120-kDa LAD-1 and 97-kDa LABD97 antigens). Other antigens targeted predominantly by IgG autoantibodies included: BP230 in 34 (27%), beta4 integrin in 26 (21%), and laminin 5 in three (2%). All the BP230+ sera and 23 (88%) beta4 integrin+ sera also reacted with at least one of the BP180 antigens. Over 85% of patients with reactivity to beta4 integrin had ocular involvement. In most cases of MMP, more severe clinical features were associated with antibody reactivity to multiple basement membrane zone antigens, as well as reactivity to multiple BP180 component antigens. Dual BP180/LAD-1 reactivity with IgG and IgA was associated with a more severe phenotype. In addition, the subset-dependent autoantibody reactivity correlated well with specific HLA class II alleles, DQB1*0301, DRB1*04 and DRB1*11. CONCLUSIONS: Our results confirmed that BP180 is a major autoantigen targeted by the sera of patients with MMP. The disease-prevalent HLA class II alleles and humoral autoimmune response against the particular subsets of antigenic epitope(s) within BP180 ectodomain may contribute to the clinicopathological significance and disease severity of MMP.

Discoid lupus erythematosus with secondary amyloidosis.

BACKGROUND: Secondary localized cutaneous amyloidosis is a clinically unapparent phenomenon associated with various cutaneous pathologies, usually tumours of epidermal origin. The amyloid is thought to be derived from keratinocytes. OBJECTIVES: To characterize the amyloid deposition observed incidentally within lesional biopsies from three patients with discoid lupus erythematosus (DLE), and retrospectively to study the phenomenon within DLE skin samples. METHODS: Localized amyloid deposition was observed in three cases of DLE by immunofluorescence studies, and these cases were further studied by histology and immunohistochemistry using a monoclonal anticytokeratin antibody. Retrospective histological review of DLE tissue specimens archived over 12 months was performed to look for evidence of previously undetected amyloid. RESULTS: Amyloid deposition was confirmed histologically in the three index cases by staining with Congo red and thioflavin T. Positive staining with an anticytokeratin antibody demonstrated the epidermal origin of the amyloid protein. Of the 18 archived cases reviewed amyloid was retrospectively detected in one sample. CONCLUSIONS: Secondary cutaneous amyloidosis of keratinocyte origin can be seen in DLE lesions. It may be a not infrequent occurrence and may remain under-reported. We discuss the possible role of disease chronicity and colloid body degradation in the pathogenesis of amyloidosis.

Evaluation of a BP180-NC16a enzyme-linked immunosorbent assay in the initial diagnosis of bullous pemphigoid.

BACKGROUND: Bullous pemphigoid (BP) is the most common subepidermal immunobullous disease, characterized by circulating IgG autoantibodies targeting BP180 and BP230 hemidesmosomal proteins. Several immunological studies have demonstrated that the membrane proximal noncollagenous domain NC16a of BP180 is the immunodominant region targeted by BP autoantibodies. Recently, a commercial BP180 NC16a-specific enzyme-linked immunosorbent assay (ELISA) has become available for detecting pathogenic anti-BP180 autoantibodies in BP sera. However, it remains unclear whether the diagnostic potential of the ELISA is equivalent to that of the 'gold-standard' diagnostic technique of immunofluorescence (IF). OBJECTIVES: To examine the usefulness of a commercially available BP180-NC16a ELISA in the initial serodiagnosis of BP. METHODS: Sera from a large cohort of patients with BP (n = 102) and control subjects (age- and sex-matched normal volunteers, n = 60; pemphigus foliaceus, n = 18; pemphigus vulgaris, n = 16) were assayed by BP180-NC16a ELISA. All BP sera were obtained at presentation before initiation of systemic immunosuppressive therapy. The values of IgG antibody levels measured by ELISA were compared with those measured by indirect IF on salt-split skin. Results Receiver operating characteristic analysis was used to calculate the cut-off value for the ELISA in the diagnosis of BP which maximizes both sensitivity and specificity, and to estimate the diagnostic accuracy of the ELISA as represented by the area under the curve (AUC = 0.965). A cut-off value of 9 was associated with a sensitivity of 89% (91 of 102 BP sera showed a positive result) and a specificity of 98%. Fifty-eight of 60 normal controls and all the pemphigus sera showed a negative result. There was a correlation between the mean ELISA values and indirect IF titres (Spearman rank correlation 0.286; P = 0.004). CONCLUSIONS: Our results suggest that the BP180-NC16a ELISA is a useful tool for the detection of pathogenic anti-BP180 IgG autoantibodies at the initial disease stage of BP. Because it is not only highly sensitive and specific, but is also easy to perform, is objective, and semiquantitative, the ELISA may provide valuable information for the accurate and reliable serodiagnosis of BP.

Paraneoplastic pemphigus secondary to fludarabine evolving into unusual oral pemphigus vegetans.

We report a patient with chronic lymphocytic leukaemia who developed paraneoplastic pemphigus (PNP) soon after the initiation of fludarabine therapy. He presented with severe oral and cutaneous erosions. Initially, he had high titres of circulating autoantibodies as detected by indirect immunofluorescence (IF) on multiple epithelial substrates (normal human skin, monkey oesophagus, and rat bladder) and by desmoglein 1 and 3 enzyme-linked immunosorbent assays (ELISAs). His oral erosions have subsequently progressed into unusual hyperplastic papillomatous lesions affecting the inner aspect of lips and buccal mucosae, histologically consistent with pemphigus vegetans. Desmoglein 1 antibodies and IF on rat bladder substrate have become negative after 18 months of therapy. Several agents had been initiated to bring the disease under control originally, but a partial remission was achieved and maintained with mycophenolate mofetil and low-dose prednisolone.