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G Kirtschig

Publications and source records attributed to G Kirtschig.

At least 37 records · Page 2Linked to original sources

Bullous pemphigoid: correlation of mucosal involvement and mucosal expression of autoantigens studied by indirect immunofluorescence and immunoblotting.

Twenty patients with bullous pemphigoid were studied prospectively: sequential sera, in different phases of the disease, were collected over a period of approximately 2 years. The sera were tested using standard immunofluorescence techniques with salt-split and intact human tissue from different sites of the body (thigh, breast, oral mucosa, vagina); an early serum of each patient was tested by Western blotting. The concentration of circulating antibodies detected by the intact skin and intact mucous membranes was similar; split tissue was more sensitive than intact tissue. For eight of 19 patients, split vagina and occasionally split oral mucosa (in the same patients) were much less sensitive than all other tissues. Furthermore, there was a correlation between autoantibody reactivity with split mucous membrane tissues and clinical mucosal involvement. These results strongly suggest heterogeneity of antigens or epitopes expressed between tissues. In both split skin and mucosa all sera consistently detected an antigen on the epidermal side of the split regardless of the stage of the disease. Immunoblotting studies showed no correlation between specific antigens and mucosal expression or skin involvement.

Aged↗

IgA basement membrane zone autoantibodies in bullous pemphigoid detect epidermal antigens of 270-280 kDa, 230 kDa, and 180 kDa molecular weight by immunoblotting.

Bullous pemphigoid (BP) is an acquired subepidermal blistering disease characterized by circulating IgG autoantibodies binding to the 230 and 180 kDa hemidesmosomal proteins. Associated basement membrane zone (BMZ) autoantibodies of the IgA class have been reported in few BP patients. The incidence and clinical relevance of these IgA antibodies, as well as their target antigens are unknown. Sera of 26 patients with BP were analysed for circulating IgG- and IgA-anti-BMZ autoantibodies by indirect immunofluorescence on salt-split human skin. All of the patients had circulating IgG autoantibodies and, in addition, nine (35%) also had circulating anti-BMZ IgA antibodies, that bound to the epidermal side of salt-split skin. By immunoblotting, IgA antibodies in seven of nine sera recognized either the 180 kDa, the 230 kDa, or both BP antigens. Moreover, IgA anti-BMZ antibodies in seven sera also detected an epidermal protein of 270-280 kDa. IgA antibodies did not identify specific bands on immunoblots of dermal extracts. There was no clinical difference between BP patients with or without circulating anti-BMZ-IgA.

Aged↗

[Autoantigens of cicatricial pemphigoid and their pathogenetic significance].

Cicatrical pemphigoid (CP) comprises a group of patients with a chronic subepidermal blistering disease which primarily involves mucous membranes; lesions characteristically heal with scarring. Immunofluorescence investigations typically demonstrate deposits of tissue bound and circulating immunoreactants of the IgG and less frequently of the IgA class in a linear pattern along the basement membrane zone. These autoantibodies are thought to play an important role in the blister formation of CP. Most patients show binding to the bullous pemphigoid antigen 2 (BPag2), collagen type XVII, with a molecular-weight of 180 kD. A smaller group of patients with CP have autoantibodies to laminin 5. Animal models confirm that autoantibodies binding to these two adhesion molecules (BPag2 and laminin 5) are important in blister formation. There are other autoantigens described in CP; however, they are only found in small groups of CP patients and most of them are not further characterised. The described molecules are part of the hemidesmosomal adhesion complex. Impaired function of any component of this complex may lead to a separation of the epidermis from the dermis; better knowledge about the single molecules and the exact localisation of epitopes within these molecules may lead to further understanding of the clinical picture.

Autoantibodies↗

Acquired junctional epidermolysis bullosa associated with IgG autoantibodies to the beta subunit of laminin-5.

We report the case of a 72-year-old man with clinical features resembling those of non-lethal junctional epidermolysis bullosa associated with IgG autoantibodies to the beta chain of laminin-5. The patient presented with a sudden onset of blistering and severe fragility of the skin and mucous membranes resulting in atrophic scars. Electron microscopy showed that the blistering arose in the lamina lucida. Indirect immunofluorescence indicated that the autoantibodies bound to the dermal side of 1 mol/L NaCl-split skin, and both direct and indirect immunoelectron microscopy demonstrated antibody binding to the lamina densa. Postembedding immunogold electron microscopy also revealed labelling in the lamina lucida beneath the hemidesmosomes. On immunoblotting, we found the autoantibodies to comigrate with the beta chain of laminin-5. Following the nomenclature of inherited junctional epidermolysis bullosa with mutations of the laminin-5 gene, we propose the name acquired junctional epidermolysis bullosa for this newly recognized disease.

Aged↗

Desquamative gingivitis and balanitis--linear IgA disease or cicatricial pemphigoid?

A 38-year-old man presented with gingival inflammation together with erosions of the penis. Direct immunofluorescence demonstrated linear deposits of IgA at the basement membrane zone; indirect immunofluorescence and immunoblotting were negative. Linear IgA disease (LAD) was therefore suspected and treatment with dapsone initiated but this was changed to sulfamethoxy-pyridazine and systemic corticosteroids because of methaemoglobinaemia. During 1-year follow-up the lesions continued to wax and wane although they were never as extensive as before. Eighteen months after disease onset there was scarring of the penis together with suspected fibrosis of the inflamed gingival region. In addition the patient was HLA DQ7(3) positive, a haplotype thought to be increased in patients with cicatricial pemphigoid (CP); LAD with scarring or CP with solely linear IgA deposits are possible diagnoses of his condition.

Adult↗

IgA-epidermolysis bullosa acquisita in a child resulting in blindness.

Epidermolysis bullosa acquisita (EBA) is an acquired subepidermal bullous disease characterized by IgG autoantibodies directed against type VII collagen, the major component of anchoring fibrils. The classical phenotype of EBA is a non-inflammatory, mechanobullous disease resembling the dystrophic forms of inherited epidermolysis bullosa. Mucous membrane involvement is frequent but usually mild. We report a 1-year-old girl suffering from IgA-EBA, who presented with an initial eruption of disseminated urticarial lesions and tense blisters of the skin but subsequently developed severe oral and ocular lesions reminiscent of cicatricial pemphigoid. Direct immunofluorescence of the skin and buccal mucosa revealed linear IgA and C3 at the basement membrane zone (BMZ). IgA anti-BMZ autoantibodies stained the dermal side of salt-split skin by indirect immunofluorescence and recognized a dermal protein of 290 kDa co-migrating with type VII collagen by immunoblotting. Direct and indirect immunoelectron microscopy revealed IgA deposits overlying the anchoring fibrils. The ocular involvement led to total blindness in spite of intense treatment. This case of childhood IgA-EBA is particularly striking because of the cicatricial pemphigoid phenotype with severe ocular involvement which resulted in blindness. It reinforces the necessity to use modern immunological methods to classify autoimmune bullous diseases in order to allow early and appropriate treatment.

Autoantibodies↗

Superciliary upsweep or tented eyebrows. A distinct mendelian trait.

Facial appearance is influenced by the anatomic relationship of the eyebrows and eyelids. Anatomic variants may characterize members of a pedigree and thus constitute a family mark. We studied three white families with circumscribed upward slanting eyebrows. In one pedigree the family mark was inherited over four generations, suggesting an autosomal dominant inheritance. In the other two families the eyebrow variation was documented in three members over two generations, compatible with an autosomal dominant mode of transmission. In two families the expression of the trait varied in the form of both bilateral and unilateral involvement. No diseases or malformations were associated with this eyebrow anomaly.

Eyebrows↗

Plectin deficiency results in muscular dystrophy with epidermolysis bullosa.

We report that mutation in the gene for plectin, a cytoskeleton-membrane anchorage protein, is a cause of autosomal recessive muscular dystrophy associated with skin blistering (epidermolysis bullosa simplex). The evidence comes from absence of plectin by antibody staining in affected individuals from four families, supportive genetic analysis (localization of the human plectin gene to chromosome 8q24.13-qter and evidence for disease segregation with markers in this region) and finally the identification of a homozygous frameshift mutation detected in plectin cDNA. Absence of the large multifunctional cytoskeleton protein plectin can simultaneously account for structural failure in both muscle and skin.

Amino Acid Sequence↗

Acquired subepidermal bullous diseases associated with psoriasis: a clinical, immunopathological and immunogenetic study.

Clinical, immunopathological and immunogenetic studies of four patients with a subepidermal bullous disease associated with psoriasis were carried out to determine the true nature of the blistering disease and to investigate further the relationship between psoriasis and acquired subepidermal bullous diseases. Autoantibodies in all four patients bound to the epidermal side of salt-split skin by indirect immunofluorescence and detected the major bullous pemphigoid (BP) antigens by immunoblotting. One had additional IgA autoantibodies binding an epidermal polypeptide of 270/280 kDa and another had circulating IgG autoantibodies which detected both BP and epidermolysis bullosa acquisita (EBA) antigens. All patients had active psoriasis at the onset of the bullous disease. Three patients were being treated with tar when blisters developed; one patient also received UVB radiation and experienced a relapse after exposure to sunlight. HLA phenotypes in three patients were determined. All the patients responded well to methotrexate. These findings demonstrate that BP is the subepidermal bullous disease most associated with psoriasis. Changes at the basement membrane zone in psoriasis may be responsible for the heterogeneous antibody response and may trigger the bullous disease, as may antipsoriatic treatment including tar and UV radiation. However, common immunogenetic mechanisms may play a crucial part in this disease association.

Aged↗

Anti-basement membrane autoantibodies in patients with anti-epiligrin cicatricial pemphigoid bind the alpha subunit of laminin 5.

Recent studies have identified a group of cicatricial pemphigoid patients who have IgG anti-basement membrane autoantibodies that recognize epiligrin, a set of disulfide-linked polypeptides closely related if not identical to laminin 5 (formerly called kalinin, nicein, or BM600). To further understand the pathophysiology of blister formation in these patients, we have sought to identify the specific polypeptide(s) targeted by their autoantibodies. Comparative studies show that sera from these patients (nine of nine), P1E1 monoclonal anti-epiligrin antibody, and polyclonal as well as monoclonal anti-laminin 5 antibodies immunoprecipitate the same set of disulfide-linked polypeptides from media of biosynthetically radiolabeled human keratinocytes. Moreover, sera from eight of nine patients with anti-epiligrin cicatricial pemphigoid immunoblot the alpha subunit of laminin 5 but show no reactivity to its beta or gamma subunits. In addition, circulating IgG from a representative patient was affinity-purified against the alpha subunit of laminin 5 and shown to bind the dermal side of 1 M NaC1 split skin in the same manner as autoantibodies from all patients with anti-epiligrin cicatricial pemphigoid. Sera from patients with bullous pemphigoid (n = 5), other forms of cicatricial pemphigoid (n = 5), epidermolysis bullosa acquisita (n = 4), or bullous systemic lupus erythematosus (n = 1) show no reactivity against any subunit of this laminin isoform in immunoprecipitation or immunoblot experiments. These findings correlate with prior reports showing that a monoclonal antibody directed against the alpha subunit of laminin 5 (i.e., laminin subunit alpha 3) induces detachment of human keratinocytes from extracellular matrix in vitro as well as epidermis from human skin in situ. Together, these studies suggest that laminin subunit alpha 3 mediates attachment of basal keratinocytes to epidermal basement membrane and that autoantibodies directed against it may be pathogenic.

Adult↗

Studies of patients with anti-epiligrin cicatricial pemphigoid.

We have recently identified patients with a form of cicatricial pemphigoid who have IgG anti-basement membrane autoantibodies directed against epiligrin, a laminin isoform closely related if not identical to laminin 5. These patients' autoantibodies bind the lower lamina lucida of human epidermal basement membrane and immunoprecipitate this laminin isoform from extracts and media of biosynthetically radiolabeled human keratinocytes. Immunoblot studies show that these patients' autoantibodies specifically bind the alpha subunit of this laminin (i.e., laminin subunit alpha 3). We have found no evidence of these autoantibodies in normal volunteers or patients with other bullous skin diseases (including those with other forms of CP). These studies have identified a group of patients with an acquired, autoimmune, subepidermal bullous disorder who have disease-specific autoantibodies directed against the alpha subunit of epiligrin/laminin 5. These findings correlate with prior reports showing that a monoclonal antibody directed against this laminin subunit induces detachment of keratinocytes from extracellular matrix in vitro as well as epidermis from human skin in situ. Together, these findings suggest that this laminin mediates attachment of basal keratinocytes to epidermal basement membrane and that autoantibodies directed against it may be pathogenic. Moreover, recent studies showing that subunits of this laminin isoform are mutated in some patients with Herlitz's junctional epidermolysis bullosa indicate that acquired or inherited abnormalities in this adhesion ligand are associated with skin diseases characterized by separation of epidermis from epidermal BM.

Autoantibodies↗

Bullous systemic lupus erythematosus: revised criteria for diagnosis.

Blistering in systemic lupus erythematosus has been divided into three groups. A specific subgroup of 'bullous systemic lupus erythematosus' has been defined by Gammon et al. on the basis of a number of criteria. From our experience of seven patients with bullous systemic lupus erythematosus, and after reviewing the literature, we suggest that the current classification is too narrow. Our patients displayed clinical and immunohistological (based on direct and indirect immunofluorescence and Western immunoblotting) heterogeneity. Sera from two patients bound to epidermal epitopes in sodium chloride-split skin, but immunoblotting was negative. In neither of these patients could the target antigen be type VII collagen, the only antigen identified as pathogenic in this disease. Patients with epidermal binding should not be excluded from a diagnosis of bullous systemic lupus erythematosus. SLE is a disease in which there is a genetic predisposition to form antibodies to type VII collagen, along with other autoantibodies, many of which may be implicated in blistering. We suggest that the criteria for the diagnosis of BSLE should be revised. We define this disease as an acquired subepidermal blistering disease in a patient with SLE, in which immune reactants are present at the basement membrane zone on either direct or indirect immunofluorescence.

Adult↗

Bullous pemphigoid and multiple sclerosis: a report of three cases and review of the literature.

Three patients with longstanding multiple sclerosis (MS) who developed bullous pemphigoid (BP) are reported. All patients had immunological features of typical BP as determined by immunofluorescence and Western immunoblotting studies. The clinical features, however, differed from those observed in typical BP. In two the BP started near an indwelling catheter and two had striking involvement of the soles. None of our patients, or a further nine cases reported in the literature, had mucous membrane involvement. In MS patients BP appears to develop at a younger age. Multiple drugs were taken by the MS patients; these, however, appear not to play a role in triggering their BP. The course of BP in patients with MS is moderate, although the majority require systemic treatment.

Aged↗

Severe case of pemphigoid gestationis with unusual target antigen.

We report a severe case of pemphigoid gestationis (PG) with an unusual target antigen. The patient developed a severe itchy macular rash on the abdomen during her fifth pregnancy, at 38 weeks' gestation. The disease persisted for 8 months post-partum, and could only be controlled with high doses of systemic corticosteroids and dapsone. The diagnosis of PG was confirmed by direct and indirect immunofluorescence. A linear band of IgG and C3 was detected at the epidermal aspect of salt-split skin. Immunoblotting studies revealed circulating IgG antibodies binding to a single 200-kDa protein in epidermal extracts. Immunofluorescence studies using trypsinized human keratinocytes demonstrated uniform staining around the cell peripheries, suggesting that the target antigen was not associated with hemidesmosomes. These findings differ from the usual immunological features seen in PG, and suggest further heterogeneity of the antigens involved in PG.

Adult↗

Acquired bullous diseases of childhood: re-evaluation of diagnosis by indirect immunofluorescence examination on 1 M NaCl split skin and immunoblotting.

Acquired autoimmune bullous diseases of childhood are rare, and can be difficult to distinguish clinically. We have studied 12 children, with an initial diagnosis of bullous pemphigoid (BP) in eight patients, cicatricial pemphigoid (CP) in one, chronic bullous disease of childhood (CBDC) in one, and epidermolysis bullosa acquisita (EBA) in two. All patients had positive indirect immunofluorescence (IIF) of the BMZ with IgG. Using 1 M NaCl split skin, six patients showed epidermal binding of IgG, with additional IgA in three cases, and in five patients IgG antibodies bound a dermal protein. Immunoblotting studies revealed an antibody to type VII collagen (EBA antigen) in three patients who had a dermal pattern on IIF. Six sera reacted with an epidermal protein of 180 and/or 220 kDa, characteristic of BP and CP. One of the three IgA-positive sera detected 220- and 180-kDa epidermal proteins using anti-IgA antibody. Following these studies the diagnosis was changed in three of the children. The diagnosis of CBDC was changed to either BP or EBA because of the presence of circulating IgG autoantibodies. In two children with an initial diagnosis of BP the diagnosis was changed to EBA. We conclude that the clinical picture in bullous disorders of childhood shows considerable overlap, and is often misleading. Additional circulating IgA autoantibodies seem to be more common in BP than has been recognized previously. Indirect immunofluorescence investigation on 1 M NaCl split skin may be helpful in differentiating between BP and EBA, but does not replace immunoblotting studies. EBA is apparently more common in children than in adults. No difference was found between the children with BP and EBA with regard to the duration of disease. The long-term outlook is good, although the course may be protracted.

Adolescent↗