Binding of wheat gliadin in vitro to reticulum in normal and dermatitis herpetiformis skin

We have demonstrated by indirect immunofluorescence that wheat gliadin binds in vitro to reticulin-like fibrils present in cryostat sections of human skin, and rat liver, kidney and stomach. Gliadin was seen to bind to fibrils throughout the dermis of both normal and dermatitis herpetiformis skin, and this was particularly striking in the dermal papillae. Serum from 2 dermatitis herpetiformis patients who did not have antireticulin antibody gave reticulin staining when retested by immunofluorescence on cryostat sections of rat tissue pretreated with gliadin. Gliadin treated sections may prove useful in screening patients with gluten sensitive enteropathy for anti-gliadin antibody. Binding of gliadin to skin sites in dermatitis herpetiformis patients and subsequent deposition of antigliadin antibody at these sites may be involved in the development of skin lesions.     

Wheat protein antibodies in dermatitis herpetiformis

An enzyme-linked immunosorbent assay was used to detect class-specific antibodies to wheat protein antigens. Antibodies which we detected by this technique reacted indistinguishably with antigens prepared from crude gluten, crude gliadin, alpha-gliadin, Frazer fraction III, and subfraction B and B3 of Frazer fraction III. No sera reacted with a human serum albumin control antigen. The prevalence of IgG antibodies to wheat protein antigens was significantly greater in patients with gluten sensitive enteropathy, 12 of 17, (p = .00011) and in patients with dermatitis herpetiformis, 5 of 14, (p = .046) than in normal control subjects. Strongly positive reactions for IgG antibodies were present only in patients with gluten sensitive enteropathy or dermatitis herpetiformis. IgA antibodies to wheat protein antigens were found only in gluten-sensitive enteropathy patients. We have found this to be a sensitive, precise technique for measurement of antibodies to wheat protein antigens and feel that it will prove useful in evaluation of the role of immune complexes involving wheat protein antigens and their antibodies in the pathogenesis of dermatitis herpetiformis.     

Sensitivity and specificity of IgA-class antiendomysial antibodies for dermatitis herpetiformis and findings relevant to their pathogenic significance

The specificity and sensitivity of the recently reported IgA-class antiendomysial antibody test for gluten-sensitive enteropathy were evaluated in four double-blind studies involving the sera of fifty-seven patients with dermatitis herpetiformis who were not on a gluten-free diet and ninety-seven assorted control sera. The control sera provided by the four centers included the sera of nineteen patients with dermatitis herpetiformis and two with celiac disease who were on a gluten-free diet, the sera of five normal subjects with human lymphocyte antigens (B8 locus), the sera of thirteen patients with linear IgA bullous dermatosis, and fifty-eight other control sera, mostly from patients with other bullous diseases and other dermatoses. The frequency of IgA antiendomysial antibody in these coded studies was zero of ninety-seven control sera and thirty-four of fifty-seven sera (60%) from patients with dermatitis herpetiformis who were not on a gluten-free diet. The pathogenic role of IgA antiendomysial antibodies in dermatitis herpetiformis and celiac disease is suggested not only by their high degree of disease sensitivity and specificity but also by their formation in response to gluten challenge, their appearance before gut changes, and the in vitro binding of gliadin to the antiendomysial antibody antigen sites. These and other findings in this study and in the literature suggest that gluten-sensitive enteropathy is immunologically mediated and that IgA antiendomysial antibodies play a significant pathogenetic role.     

Circulating antibodies to gliadin subfractions in dermatitis herpetiformis and linear IgA dermatoses

Dermatitis herpetiformis (DH) and coeliac disease are associated and the rash of DH is gluten-dependent. The gliadin fraction responsible for the rash is unknown. In linear IgA dermatoses the role of gluten in the skin eruption remains controversial.
Anti-gliadin antibodies (AGA) were measured by an enzyme-linked immunosorbent assay in 10 normal controls; 35 patients with dermatitis herpetiformis (DH); 14 adults with linear IgA disease; and 13 patients with chronic bullous dermatosis of childhood. The presence of enteropathy was assessed by jejunal biopsy and intra-epithelial lymphocyte (IEL) counts.
DH with normal IEL counts on normal diet: IgG and IgA-AGA identical to controls. DH with raised IEL counts on gluten-free diet: slightly elevated IgG and IgA-AGA. DH with raised IEL counts on a normal diet: IgG and IgA were higher, with median IgG 1:2048 (control 1:512) median IgA 1:512 (control 1:128). DH patients with high IgG AGA had elevated titres to α, β, γ, and ω subfractions. The highest levels were for α and the lowest for ω.
For linear IgA disease IgG is normal but adults had raised IgA-AGA compared to controls ( P = 0.005).
In dermatitis herpetiformis the presence of anti-gliadin antibody was dependent on the degree of enteropathy, and, if present, was directed against all gliadin subfractions. The significance of the elevated IgA—AGA in the linear IgA disease is unknown.     

Dermatitis herpetiformis: close to unravelling a disease

Dermatitis herpetiformis is characterised by granular IgA precipitates in the papillary dermis. In contrast to other autoimmune blistering diseases, where tissue-deposited and circulating autoantibodies recognise the same target within the skin, in dermatitis herpetiformis a serum IgA reacting with a component of the healthy papillary dermis has not been detected. Recently, the antigenic specificity of pathognomic skin-bound IgA has been clarified: the immune precipitates contain epidermal transglutaminase, an enzyme not previously detected in the papillary region of normal skin. Furthermore, serum IgA in dermatitis herpetiformis has been found to bind epidermal transglutaminase. These findings may relate to the fact, that dermatitis herpetiformis is associated with gluten sensitive enteropathy, coeliac disease, which is characterised by IgA type autoantibodies to a closely related enzyme, tissue transglutaminase. The two transglutaminases are highly homologous, and therefore, cross reactivity of the two antibodies might explain why patients with gluten sensitive enteropathy, with or without skin disease, generally have serum autoantibodies to both enzymes. There is growing evidence that dermatitis herpetiformis should be considered as the skin manifestation of gluten sensitivity developing in those patients with mild coeliac disease, who produce epidermal transglutaminase autoantibodies of high avidity and affinity. Both the skin and the small bowel diseases are gluten dependent and are strongly associated with HLA DQ with no genetic differences to explain the two phenotypes. The question should be asked whether the rash in dermatitis herpetiformis is a classic autoimmune blistering disease or whether it has an immune complex basis, which is the most likely alternative.     

Class-specific antibodies to gluten in dermatitis herpetiformis

An immune reaction to wheat protein has been previously proposed to explain the pathogenesis of dermatitis herpetiformis. In order to detect and characterize antibodies to gluten in human sera, we developed an enzyme immunoassay for class-specific antibodies. Results of this assay in 49 patients with dermatitis herpetiformis were compared with those of 38 normal control subjects, 11 patients with celiac disease, and 6 small-bowel bypass patients. IgA antibodies to gluten were significantly more frequent in dermatitis herpetiformis sera (28/49) than in normal control sera (4/38). IgG antibodies to gluten were significantly more frequent in both celiac disease (10/11) and dermatitis herpetiformis (16/49) sera than in control (5/38) sera. Dermatitis herpetiformis sera also had an increased prevalence of IgM antibodies to gluten (19/49). Small-bowel bypass patients demonstrated no antibody to gluten. Antibodies to gluten in dermatitis herpetiformis objectively mark a state of immune reactivity to wheat protein and may be involved in the genesis of the cutaneous IgA immune deposits and the skin disease.     

Experience with a gluten free diet in the treatment of linear IgA disease

A study was undertaken to determine whether the skin eruption of linear IgA disease (LAD) was gluten dependent. Six patients with LAD were treated with a gluten free diet (GFD) for an average period of 33 months (range 19-48). Although one patient with LAD had an enteropathy which was clearly gluten sensitive, there was no convincing evidence that the rash of any of the patients responded to a GFD. Four of the six patients showed no significant alteration in their drug requirements. The remaining 2 patients showed a fall in minimum drug requirement but there was no increase after gluten challenge indicating that they were entering spontaneous remission. This contrasts to the situation in dermatitis herpetiformis, where both the rash and the enteropathy are gluten dependent. These data add further to the evidence that LAD and dermatitis herpetiformis are separate entities.     

Juvenile dermatitis herpetiformis: an immunoelectron microscopic study

Three children with persistent maculopapular and urticarial lesions and vesicles at the predilection sites of dermatitis herpetiformis (DH) were shown to exhibit typical granular, papillary IgA and C3 deposits in the tips of the dermal papillae, as demonstrated by direct immunofluorescence. By immunoelectron microscopy, the IgA deposits were associated with the microfibrils of the elastic fibres as has been described in DH of the adult. C3 deposits were scattered throughout the papillary dermis. Despite the similarity of the clinical appearance, history with regard to gluten sensitive enteropathy (GSE) varied in these three cases. In one child, the skin lesions appeared following faults in the gluten free diet on which he was kept for coeliac disease. Another child developed the skin lesions during a gluten free diet which was not strictly followed; no recurrences of gastrointestinal symptoms accompanied the eruption of DH. In the third case, no evidence for GSE in patient's history or in jejunal biopsies was present at the time of onset of DH.     

Two Japanese cases of dermatitis herpetiformis associated each with lung cancer and autoimmune pancreatitis but showing no intestinal symptom or circulating immunoglobulin A antibodies to any known antigens

Dermatitis herpetiformis (DH) is common in some Caucasian populations but extremely rare in Japanese, probably because of different immunogenetic backgrounds. We report two Japanese DH cases with typical clinical, histological and direct immunofluorescence features. However, no symptom of gluten‐sensitive enteropathy was shown. The diagnosis was confirmed by eliminating other autoimmune blistering diseases by indirect immunofluorescence, enzyme‐linked immunosorbent assays and immunoblotting. However, circulating immunoglobulin (Ig)A anti‐endomysium, reticulin and gliadin antibodies were not detected. IgA antibodies to tissue and epidermal transglutaminases were also negative. One case was associated with lung cancer and the other one with autoimmune pancreatitis. On review of 17 cases of DH reported in Japan over the previous 10 years, including our cases, one case was associated with gluten‐sensitive enteropathy, four with malignant neoplasms, two with autoimmune systemic disorders and one with psoriasis. Although our cases were typical of DH in clinical, histopathological and IgA deposit features, they showed different human leukocyte antigen haplotypes, no gluten‐sensitive enteropathy and no DH‐specific IgA antibodies, including those to epidermal and tissue transglutaminases. These results suggest that studies of unique characteristics in Japanese DH patients should facilitate further understanding of pathogenesis in DH.     

Dermatitis Herpetiformis: Should Direct Immunofluorescence Be the Only Diagnostic Criterion?

We describe a 7-year-old boy with dermatitis herpetiformis (DH) diagnosed on clinical and histologic evidence, negative direct immunofluorescence (DIF) findings for junctional IgA deposits in uninvolved skin, positive IgA endomysial and gliadin antibodies, and jejunal biopsy revealing a gluten-sensitive enteropathy. Treatment with dapsone led to the disappearance of cutaneous lesions and pruritus within 48 hours. Demonstration of IgA immune deposits in the dermal papillae has been the only acceptable criterion for the diagnosis of dermatitis herpetiformis. However, considering several reports in the literature of DH with a negative DIF and our own case, we believe that in the absence of the characteristic DIF pattern, one needs the combination of clinical, histologic, and immunologic data to support the diagnosis of DH. We also discuss recent developments in the diagnosis of DH.     

IgA anti‐epidermal transglutaminase autoantibodies: a sensible and sensitive marker for diagnosis of dermatitis herpetiformis in adult patients

Background Dermatitis herpetiformis (DH) is a rare gluten‐sensitive blistering itchy skin disease, strictly related to coeliac disease (CD). Direct immunofluorescence, demonstrating IgA granular deposits localized either in the dermal papillae or along the dermo‐epidermal junction, is currently the gold standard for diagnosis of DH. It has been shown that DH immunocomplexes contain epidermal transglutaminase (eTG) and that sera from patients with DH contain antibodies specifically directed against eTG. Objectives We studied the usefulness of serum eTG antibodies in discriminating between DH, CD and other gastrointestinal and dermatologic diseases. Methods eTG antibodies were tested in 308 adult patients’ sera: 44 patients with untreated dermatitis herpetiformis (UDH), 99 patients with untreated coeliac disease (UCD), 70 dermatological controls and 95 gastrointestinal controls. Results In UDH eTG antibody levels were significantly higher than in DH patients on gluten‐free diet, UCD, gastrointestinal controls and dermatological controls. In UCD eTG antibodies strongly correlated with tissue transglutaminase (tTG) antibodies, whereas in UDH no significant correlation was observed. Conclusion Serum IgA eTG antibody determination can efficiently distinguish UDH from other dermatological itchy diseases and is highly sensitive to gluten‐free diet.     

Familial incidence of dermatitis herpetiformis

Dermatitis herpetiformis and gluten-sensitive enteropathy are diseases in which exposure to gluten results in an inflammatory response. Both diseases are associated with certain human lymphocyte antigen alleles, and gluten-sensitive enteropathy is well known to cluster in families. Gluten-sensitive enteropathy has also been reported in families of patients with dermatitis herpetiformis. Despite this evidence that dermatitis herpetiformis is a genetic disease, reports of the familial occurrence of dermatitis herpetiformis are rare. We have obtained family histories from 92 patients with dermatitis herpetiformis with 740 first-degree relatives. Six of these relatives have dermatitis herpetiformis. Comparison of these data with the expected prevalence of dermatitis herpetiformis shows this incidence to be highly significant (p less than 0.0001), strongly suggesting that dermatitis herpetiformis is a familial disease, presumably because of shared genetic factors but possibly because of a shared environment.     

Antiendomysial antibody — useful serological indicator of dermatitis herpetiformis

Summary Antiendomysial antibodies (EmA) of the IgA class are directed against reticulin components of the primate smooth muscle and are markers of gluten-sensitive enteropathy. These antibodies occur in essentially all active cases of celiac disease and in about 70% of dermatitis herpetiformis (DH) patients. IgA deposits in the dermal papillae of the skin are the hallmark of DH and are employed routinely in establishing its diagnosis. The incidence of IgA deposits in skin varies depending upon the site and type of biopsy specimen taken.We studied sera and skin biopsy specimens for EmA and for IgA deposits in the skin from 11 DH patients. EmA were detected in the sera of 10 of the 11 cases. Of these 11 patients, 9 were positive for IgA deposits in their skin, as revealed by direct immunofluorescence (IF). The immune deposits were detected in the normal, and not in the lesional skin. DH cases that were initially negative on biopsy and serum positive for EmA were found to be positive when a repeat biopsy of the normal skin was performed. Thus, serological studies in conjunction with direct IF studies of the normal skin are useful in making a diagnosis of DH.Presented at the Society for Investigative Dermatology Meeting, Washington, DC, May 2, 1986     

Concordance of dermatitis herpetiformis and celiac disease in monozygous twins

Celiac disease can be defined as the classical manifestation of gluten sensitivity, which primarily affects the small intestine. Gluten sensitivity has also a skin manifestation, i.e., dermatitis herpetiformis. Both diseases have a strong genetic association with HLA DQ on chromosome 6. In this study we tried to estimate how much different clinical expressions of gluten sensitivity are determined by genetic factors, and hence how feasible they are for genetic mapping; therefore, we studied all six monozygous twin pairs found among 1292 prospectively collected patients of dermatitis herpetiformis in Finland. Three of the six twin pairs were concordant for dermatitis herpetiformis and for simultaneous enteropathy, celiac disease. Two other twin pairs were partially discordant, one of each pair had dermatitis herpetiformis and celiac disease, whereas the other had solely the gut manifestation of gluten sensitivity, i.e., celiac disease. Only one pair was found to be discordant for gluten sensitivity. All the pairs had typical risk alleles for gluten sensitivity, i.e., either HLA DQ2 or DQ8. These results demonstrate that the genetic component in gluten sensitivity as broadly defined is very strong (5/6 concordant). Genetically identical individuals can have clearly distinguished phenotypes, either dermatitis herpetiformis or celiac disease, suggesting that environmental factors determine the exact phenotype of this multifactorial disease. These findings are of importance in genetic linkage analyses, which focus to only certain phenotypic properties of a complex trait.     

Circulating antibodies to gliadin subfractions in dermatitis herpetiformis and linear IgA dermatosis of adults and children

Dermatitis herpetiformis (DH) and coeliac disease (CD) are linked but their association with linear IgA dermatosis (LAD) is unclear. Thirty-seven patients with DH and 27 with linear IgA dermatosis were investigated, of which 23/37 DH patients and 1/10 LAD patients had small intestinal enteropathy. Elevated IgG and IgA gliadin antibodies were found in the DH patients with enteropathy (CD). IgG gliadin antibodies in DH patients were directed against alpha, beta, gamma and omega gliadin subfractions. Elevated IgA gliadin antibodies in the adult LAD patients (n= 14) suggests that this condition may be associated with enteropathy or an IgA diathesis.     

Circulating IgA- and IgG-class antigliadin antibodies in dermatitis herpetiformis detected by enzyme-linked immunosorbent assay

Summary A sensitive and technically simple enzymelinked immunosorbent assay (ELISA) was developed to demonstrate circulating IgA- and IgG-class antibodies to gliadin, a component of wheat gluten. Serum samples from 24 patients with dermatitis herpetiformis (DH), 5 with coeliac disease (CD) and 75 normal controls were analysed. Antigliadin antibodies (AGA) of the IgA class were detected in 71% of DH patients, all of the CD patients and 19% of the controls. IgG-AGA was found in over 90% of DH patients and controls and in all of the CD patients. The mean ELISA values of both IgA- and IgG-class AGA were significantly higher in DH patients than in the controls. The occurrence of circulating IgA-class AGA is compatible with the hypothesis that these antibodies can be deposited in the skin, e.g. as immune complexes, or due to cross-reactivity of gliadin and dermal reticulin.Supported by grants from the Foundation for Finnish Chemical Research     

Wheat grain immunofluorescent antibodies as an indication of gluten sensitivity?

An immunofluorescence method using whole sections of wheat grains as the substrate was applied to detect circulating antibodies to wheat gluten in dermatitis herpetiformis patients and in controls. Only IgG class antibodies were detected. From dermatitis herpetiformis patients 22% had these antibodies as had 22% of the atopic dermatitis group. Among the controls who had no skin problems 12% were faintly positive. It is evident that the test as such is non-specific and does not have diagnostic significance in dermatitis herpetiformis.     

TCR Vbeta expression in the small bowel of patients with dermatitis herpetiformis and gluten sensitive enteropathy. Limited expression in dermatitis herpetiformis and treated asymptomatic gluten sensitive enteropathy

Dermatitis herpetiformis (DH) is a blistering skin disease characterized by cutaneous deposits of IgA and an associated, most often asymptomatic, gluten sensitive enteropathy (GSE). Gluten sensitive enteropathy is also seen in patients that do not have skin disease or cutaneous IgA deposits, but do have significant gastrointestinal (GI) complaints. Patients with DH and with GSE without skin disease have similar small bowel morphologic changes and HLA associations and both the skin disease and the GI symptoms can be controlled by a gluten free diet. It is not known what factors allow almost all patients with DH to continue to eat gluten and not develop symptomatic gastrointestinal disease. We have examined the expression of the Vbeta T-cell receptor (TCR) in the small bowel of patients with DH (n=11) and of patients with both symptomatic (n=10) and asymptomatic (n=7) GSE without skin disease to determine if differences in the pattern of TCR Vbeta expression are associated with differences in the clinical manifestations of these diseases. TCR Vbeta expression was analyzed using RT-PCR from small bowel biopsies. Patients with DH and those with GSE without skin disease that were on a gluten free diet and asymptomatic were found to express 6.6 and 5.6 out of 20 Vbeta families respectively, with no single family preference. Examination of peripheral blood lymphocytes from these patients did not reveal any restriction of TCR Vbeta family expression. In contrast, patients with symptomatic GSE expressed 12.6 Vbeta families (P< 0.05), with no consistent preferential expression of any single Vbeta family between patients. Patients with DH, who are continuing to ingest wheat, show a more restricted pattern of TCR Vbeta utilization, similar to that of treated patients with GSE without skin disease, and significantly different from GSE without skin disease patients eating gluten. These findings suggest that the restricted nature of the TCR Vbeta expression may play a role in the different clinical manifestations of dermatitis herpetiformis and isolated gluten sensitive enteropathy.     

IgA antiendomysial antibodies in dermatitis herpetiformis

Sera from 24 patients with dermatitis herpetiformis and 80 control subjects (patients with other bullous diseases, nonbullous dermatoses, and noncutaneous diseases) were studied to determine the usefulness of assay for IgA antiendomysial antibodies (IgA-EMA) in the diagnosis of dermatitis herpetiformis. The overall sensitivity of IgA-EMA for the diagnosis of dermatitis herpetiformis was 79% and the specificity was 96%. When the three patients with dermatitis herpetiformis who were faithfully following gluten-free diets were excluded, the sensitivity was 90% and the specificity was 96%. No patient in the bullous disease control group (including patients with linear IgA bullous dermatosis) had circulating IgA-EMA. One patient, who did not have direct immunofluorescence evidence for dermatitis herpetiformis but had IgA nephropathy, had a positive IgA-EMA result, an interesting association in light of the rare reports of dermatitis herpetiformis in patients with IgA nephropathy and IgA antigliadin antibodies associated with IgA nephropathy. Although direct immunofluorescence testing of skin biopsy specimens remains the most definitive diagnostic test for dermatitis herpetiformis, indirect immunofluorescence assay of serum for IgA-EMA is a minimally invasive study with a high sensitivity and specificity for dermatitis herpetiformis.     

Increased gliadin antibodies in dermatitis herpetiformis and pemphigoid

The mean titres of serum IgG and IgA gliadin antibodies were significantly increased in thirty-four patients with bullous pemphigoid, and in twenty-three patients with dermatitis herpetiformis, compared with twenty-four healthy controls. The patients with pemphigoid also had increased IgG and IgA gliadin antibodies compared with nine patients with pemphigus. The reason for the high titres of gliadin antibodies in pemphigoid is obscure. These patients may have increased intestinal permeability (suggested by the presence of beta-lactoglobulin antibodies in some patients). Alternatively gliadin may somehow precipitate the autoimmune process.