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1.
IgG antibodies from the sera of some patients with bullous pemphigoid (BP) react with a 180 kDa protein termed BPAg2. Antibodies in BP are directed to an extracellular noncollagenous domain of this protein termed NC16A. Our group has recently shown that a portion of the extracellular domain of BPAg2 is identical to LABD97 on the basis of amino acid sequencing. We evaluated sera from 33 patients with BP with circulating IgG antibodies on indirect immunofluorescence, which stained the epidermal side of split skin with titers ranging from 1:40 to 1:640. Immunoblotting was performed against (i) two preparations of proteins from epidermal extract, one containing BPAg2 and one containing LABD97, and (ii) the recombinant NC16A domain of the BPAg2 protein. Twelve sera reacted with the BPAg2 protein. Ten of these also reacted strongly with the NC16A domain. Nine of the 12 sera also reacted with the LABD97 antigen. Bound antibodies were eluted from the 97 kDa band and reapplied to split skin where they bound to the epidermal side. The eluted antibodies also reacted to the BPAg2 protein from the epidermal extract, but did not react with the NC16A domain on immunoblot. We conclude that these nine sera react with an epitope present within BPAg2 and LABD97 but not within the NC16A domain. This epitope is therefore distal to the previously described epitopes in BP. In BP, epitope spreading may occur and antibodies may be produced that recognize the distal portion of the BPAg2 molecule identical to LABD97 but that do not involve the NC16A domain.  相似文献   

2.
OBJECTIVE: To determine the diagnostic value of indirect immunofluorescence on sodium chloride-split skin (SSS) in differentiating the pemphigoid group of subepidermal autoimmune bullous dermatoses, including bullous pemphigoid (BP), cicatricial pemphigoid, and pemphigoid gestationis, from epidermolysis bullosa acquisita (EBA). DESIGN: Serum samples were tested using immunofluorescence on SSS and immunoblot assay on epidermal and dermal extracts, a recombinant protein corresponding to the C-terminal end of the 230-kd BP antigen, and purified laminin-5. SETTING: An immunodermatology laboratory. PATIENTS: One hundred forty-two serum samples from patients with BP (n = 98), cicatricial pemphigoid (n = 23), pemphigoid gestationis (n = 10), EBA (n = 10), and anti-type IV collagen (n = 1). MAIN OUTCOME MEASURES: Binding sites of serum to the epidermal and/or dermal sides of SSS were correlated with their antigenic specificities. RESULTS: Epidermal staining on SSS was highly specific for pemphigoid. Alternatively, a poor correlation was found for the dermal-reacting serum samples and the diagnosis of EBA; of the 19 serum samples with dermal staining on SSS, only 10 reacted with the EBA antigen. The remaining serum samples were from patients with cicatricial pemphigoid having antibodies to the alpha 3 or beta 3 chains of laminin-5 (n = 5) or patients with BP having antibodies to the 180-kd BP antigen (n = 2). One sample recognized exclusively a 185-kd dermal antigen corresponding to type IV collagen. One more BP serum sample with dermal staining did not recognize any dermal or epidermal antigen. CONCLUSION: In case of immunofluorescent dermal staining, the precise diagnosis should be confirmed by identification of the involved antigen, since it may reveal antibodies to laminin-5 or type XVII or IV collagen, in addition to the EBA antigen.  相似文献   

3.
Bullous pemphigoid (BP) is an autoimmune blistering disease of the skin. Several variants of BP have been described but until recently the relationship of these variants to generalized BP was unclear. Several studies have shown that pemphigoid nodularis, pemphigoid vegetans, localized BP and vesicular pemphigoid are true variants of BP as the circulating antibodies in these patients recognize the same 230 kDa BP antigen as found in patients with generalized BP. Erythrodermic BP is a very unusual variant characterized by an erythroderma along with blister formation. We describe the third known patient to develop erythrodermic BP and characterize the antigenic specificity of the circulating antibodies in both our newly reported patient with erythrodermic BP and in one of the two other previously reported cases of erythrodermic BP. Both patients with erythrodermic BP had circulating IgG antibodies which bound to the epidermal side of salt-split human skin in a pattern identical to two patients with immunopathologically proven generalized BP. Sera from four erythrodermic patients without blisters and from a healthy normal volunteer, as controls, failed to demonstrate detectable circulating IgF autoantibodies. Immunoprecipitation studies revealed that both patients with erythrodermic BP had circulating IgG autoantibodies which recognized, to varying degrees, the same 230 and 180 kDa BP antigens as recognized by sera from two patients with immunopathologically proven generalized BP. Sera from four erythrodermic patients without blisters and from a healthy normal volunteer, as controls, failed to recognize any specific polypeptides. These observations demonstrate that erythrodermic BP is a distinct clinical variant of BP.  相似文献   

4.
Sera from patients with bullous pemphigoid (BP) from the United States (US), Japan, and Britain demonstrate similar reactivity to the major target antigens BPAG1 and BPAG2. The purpose of the present study was to determine if the epitope specificity of circulating autoantibodies in patients with BP from the US and Japan is similar as mapped by binding to fusion proteins encoded by BPAG1. Sera from patients and controls with BP from the US and Japan were assayed for reactivity to intact BPAG1 and BPAG2 by immunoblot, and to fusion proteins encoded by BPAG1 by immunoblot and enzyme-linked immunosorbant assay (ELISA). Significant reactivity to fusion proteins encoded by the carboxyl region (FP 16-8) and coiled-coil region (FP3) was seen in sera from the US and Japanese patients, but not from normal controls from the US or Japan. Sera from US and Japanese patients differed in their response to FP7; namely, the reactivity of sera from US patients but not from Japanese patients to FP7 was significantly different from the reactivity of their respective control sera. The reasons for this difference in reactivity are unknown but may reflect genetic or environmental factors relevant in the generation of an autoantibody response to these target antigens.  相似文献   

5.
Immunoblotting studies with salt-split human epidermis were performed on sera from 15 patients with pemphigus vulgaris and 20 patients with bullous pemphigoid by using peroxidase-labelled antihuman IgG and IgA. Eleven sera of pemphigus vulgaris antigen. Most of the sera gave additional specific bands at 210 and 80 kD, with lower intensity. The sera of 4 patients, 3 of them were in clinical remission, did not yield specific bands. Seventeen sera of the 20 bullous pemphigoid patients yielded a 220-230 kD protein band against the major bullous pemphigoid antigen and 4 of them gave another specific band at 160-180 kD. Five sera produced multiple bands (220, 130, 100 and 75 kD). IgA antibodies against the major bullous pemphigoid antigen were demonstrated in 2 cases with IgA deposits along their basement membrane, as revealed by direct immunofluorescence. The immunoblot patterns correlated only weakly with the clinical findings in bullous pemphigoid. There was a considerable diversity in both clinical findings and immunoblot patterns.  相似文献   

6.
Paraneoplastic pemphigus (PNP) is an autoimmune blistering disease that occurs in association with underlying neoplasms. PNP patients develop characteristic autoantibodies directed against multiple antigens, mostly identified as members of the plakin family of cytoplasmic proteins (desmoplakin I and II, bullous pemphigoid antigen I, envoplakin, and periplakin). HD1/plectin, another member of the plakin family, has not previously been detected in the characteristic PNP antigen complex, which may relate to practical difficulties associated with its large size (molecular weight approximately 500 kDa). In this study, a combination of immunoprecipitation and immunoblot is used to demonstrate that HD1/plectin is also recognized by sera from PNP patients. Thirteen of 16 PNP sera tested were positive for HD1/plectin compared with none of 43 control sera (11 pemphigus vulgaris, 11 pemphigus foliaceus, 11 bullous pemphigoid, and 10 normal individuals). Combined with our recent finding that desmoglein 3 and desmoglein 1 are cell surface target antigens in PNP, this demonstration of plectin/HD1 as another component of the antigen complex in PNP confirms that PNP is an autoimmune disease against desmoglein and plakin family molecules.  相似文献   

7.
Hyperglycemia is observed in some patients with autoimmune bullous diseases complicated by diabetes mellitus or treated with systemic corticosteroids. High concentrations of glucose can react with various proteins and change their structural and functional properties. We previously reported that nonenzymatic glycosylation of antibody can impair antigen-antibody binding. We ascertained whether glycosylation of autoantibody decreases the autoantibody titer by examining 30 sera from patients with pemphigus and pemphigoid. Nonenzymatic glycosylation in the physiological range was induced by incubation of sera with 1650 mM D-glucose at 4 degrees C for 7 days. The titers of sera were determined by indirect immunofluorescence (IIF). In all cases, the immunofluorescence intensity of glycosylated sera was weaker than that of nonglycosylated sera. Glycosylated sera showed a lower antibody titer by 1 doubling dilution in 18 out of 30 cases, compared with nonglycosylated sera. The ten BP patients' sera were also analyzed by immunoblotting for reactivity with the BP180-GST fusion proteins, S delta 1 and 4575. All BP sera reacted with S delta 1, and 5 out of 10 BP sera reacted with both S delta 1 and 4575. In all the sera that reacted only with S delta 1, the glycosylated sera showed a 1 doubling dilution decrease in autoantibody titer. Interestingly, in 4 out of 5 sera that reacted with both S delta 1 and 4575, there were no differences in the antibody titer between glycosylated and nonglycosylated sera. These results indicate the possibility of a false decrease in autoantibody titers of sera from patients with autoimmune bullous diseases complicated with hyperglycemia. Although the false decrease in titers of autoantibodies induced by nonenzymatic glycosylation is not dramatic, it must be considered in order not to underestimate the disease activity of pemphigus in such cases.  相似文献   

8.
Epidermolysis bullosa acquisita and bullous systemic lupus erythematosus are autoimmune bullous disorders, with tissue-bound and circulating autoantibodies reactive with the noncollagenous NC1 domain of type VII collagen (C-VII). Here, we describe a novel acquired bullous dermatosis with autoantibodies against the triple-helical domain of C-VII. Three patients, all Japanese children, presented with widespread inflammatory tense blisters. Histologically, subepidermal tissue separation was noted with inflammatory infiltrate in the superficial dermis. Direct immunofluorescence staining revealed linear IgG/C3 deposits along the dermal-epidermal junction. Circulating IgG anti-basement membrane zone autoantibodies stained the dermal side of normal skin separated with 1 M NaCl. Direct and indirect immunoelectron microscopy using colloidal gold labeling showed that patient sera reacted with anchoring fibrils. The gold particles were localized both near the lamina densa and on the central banded portion of the fibrils. The sera reacted with C-VII in immunoblots. Epitope analyses with natural and recombinant fragments of C-VII disclosed that the sera did not recognize the NC1 domain of C-VII, but the central triple-helical domain of this anchoring fibril protein. Thus, the present probands show a hitherto unrecognized variant of epidermolysis bullosa acquisita, with autoantibodies against epitopes in the collagenous domain of C-VII.  相似文献   

9.
Generalized atrophic benign epidermolysis bullosa (GABEB) is a rare variant of non-lethal junctional epidermolysis bullosa characterized by generalized skin blistering healing with atrophy and by atrophic alopecia with onset in childhood. Other features include mild mucosal blistering, dental abnormalities and nail dystrophy. We report four additional cases of GABEB from two families originating from the same isolated village. The patients shared an unusually mild clinical phenotype with cutaneous blisters strictly limited to trauma sites and rare occurrence of oral mucosal lesions. Scalp, eyelash and eyebrow alopecia was present in only two cases. Immunofluorescence studies showed a markedly reduced expression of the 180-kDa bullous pemphigoid antigen (BP180), and northern analysis of cultured keratinocytes indicated that the gene encoding for BP180 is affected in these GABEB patients.  相似文献   

10.
Bullous pemphigoid (BP) is an autoimmune subepidermal blistering disease characterized by deposition of autoantibodies at the basement membrane zone. In an experimental BP model in mice, the subepidermal blistering is mediated by antibodies directed against the hemidesmosomal protein BP180 (collagen XVII, BPAG2), and depends on complement activation and neutrophil infiltration. Gelatinase B is present in BP blister fluid and can cleave BP180. In this study we investigated the role of gelatinase B in the immunopathogenesis of experimental BP using mice containing targeted disruption of the gelatinase B (MMP-9, 92 kD gelatinase) gene. Gelatinase B-deficient mice were resistant to the blistering effect of intracutaneous anti-mBP180 antibodies, although these mice showed deposition of autoantibodies at the basement membrane zone and neutrophil recruitment to the skin comparable to that observed in the control mice. Interleukin 8 given intradermally concomitantly with pathogenic anti-mBP180 elicited a significant neutrophil recruitment into the skin in gelatinase B-deficient mice, but blistering did not occur. However, gelatinase B-deficient mice reconstituted with neutrophils from normal mice developed blistering in response to anti-mBP180 antibodies. These results implicate neutrophil-derived gelatinase B in the pathogenesis of experimental BP and might lead to novel therapeutic strategies for BP.  相似文献   

11.
OBJECTIVE: Epitopes on Ki antigen were analyzed using synthetic peptides, including KILT, a 16-mer peptide with an amino acid sequence homologous to the SV40 large T antigen nuclear localization signal (SV40 T NLS). METHODS: In addition to KILT, 4 synthetic peptides, all potential epitopes on Ki antigen according to computer analysis, were prepared and tested for reactivity with 49 anti-Ki-positive lupus sera by enzyme-linked immunosorbent assay. RESULTS: Eighteen sera reacted with KILT, but not with other peptides. The reaction of anit-Ki sera with KILT was specifically inhibited by recombinant Ki antigen. Eight of 49 anti-Ki sera reacted with a 7-mer synthetic peptide of SV40 T NLS, and the reaction was specifically inhibited by KILT. CONCLUSION: The 16-mer Ki peptide containing the sequence homologous to the SV40 T NLS is one of the antigenic epitopes recognized by anti-Ki antibodies in lupus sera.  相似文献   

12.
The classification of linear IgA bullous dermatosis in the group of subepidermal blistering diseases is still a matter of controversy. This situation is due partly to the considerable clinical heterogeneity of the disease but also results from the difficulties in characterization and localization of the specific basement membrane zone antigen(s) recognized by immunoglobulin (Ig)A antibodies. In the present study, we have combined the Western blot detection of circulating autoantibodies with an ultrastructural immunogold labeling of human skin antigens using the same patients' sera. Our results, obtained with a short series of sera showing exclusive IgA class reactivity with the epidermal portion of salt-split skin, indicate that the antibodies recognizing the 97-kD antigen on immunoblot bind to the hemidesmosomal plaques of basal keratinocytes and the adjacent lamina lucida. These homogeneous laboratory results remain in striking contrast to the heterogeneity of clinical pictures in the patients studied, suggesting a participation of complementary, possibly not humoral, phenomena in the pathogenesis of linear IgA bullous dermatosis.  相似文献   

13.
Bullous pemphigoid (BP) is an autoimmune blistering disease characterized in part by the presence of tissue-bound and circulating antibodies (mostly of IgG) to the basement membrane zone (BMZ). We previously reported that IgG subclasses of BP antibodies were IgG1, IgG2 and IgG4, and that only BP IgG1 fixed complements. In this study, we examined whether BP IgG sub-classes bound to the same epitope of BP antigen or a different epitope. In an inhibition immunofluorescence studies, the complement fixing capability of IgG1 was inhibited by the pretreatment with IgG4 and partially inhibited by IgG2. On immunoblot analysis, IgG1 and IgG4 were bound to the same MW of BP antigen. In enzyme-linked immunosorbent assay (ELISA), the binding capability of IgG subclass fractions from patients with BP to synthetic peptide P1-2, exceeding normal IgG subclass fractions was seen in five IgG1, one IgG2 and two IgG4, from eight BP patients. The binding capability of IgG subclass fractions from the patients with BP to P1-1, exceeding the normal IgG fractions was seen in two IgG1, three IgG2 and one IgG4 from ten BP patients. On inhibition ELISA, the binding activity to P1-2 of IgG4 was partially inhibited by the pretreatment of IgG1 and IgG2. These findings suggest that BP IgG1, IgG2 and IgG4 could bind to the same epitope though considerable variation occurred between patients.  相似文献   

14.
We report a patient with Shy-Drager syndrome who developed multiple tense blisters mainly on the extremities. Circulating anti-basement membrane zone autoantibodies were detected by the indirect immunofluorescence method. Immunoblot analysis using normal human epidermal extracts demonstrated that this patient's serum reacted only with 230 kD bullous pemphigoid antigen (BPAG1). Concerning the pathoetiology of the association of bullous pemphigoid and Shy-Drager syndrome, we discuss a sequence similarity between BPAG1 and dystonin, a candidate gene for dystonia musculorum.  相似文献   

15.
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.  相似文献   

16.
We describe a 31-year-old Japanese woman with generalized pustular psoriasis treated with PUVA who subsequently developed a bullous disease. Throughout the disease course, there was no phase of psoriasis vulgaris. Although several reports describe coexistence of psoriasis vulgaris and bullous disease such as bullous periphigoid, coexistence of generalized pustular psoriasis without any phase of psoriasis vulgaris and bullous disease is rare. As for the bullous disease, direct immunofluorescence study showed IgG and C3 deposition along the basement membrane zone. Indirect immunofluorescence disclosed IgG antibasement membrane zone antibodies. Indirect immunofluorescence on 1 mol/l sodium chloride-split skin demonstrated linear IgG staining almost exclusively on the dermal side of the split. Western immunoblot analysis revealed that the antibody was directed to neither epidermolysis bullosa acquisita antigen nor bullous pemphigoid antigens. Considering the unusual clinical course, we suspect the possibility of a novel autoimmune blistering disease.  相似文献   

17.
Three siblings of Swiss origin with epidermolysis bullosa junctionalis progressiva are described. The following clinical features were present from school age: dystrophy of the nails, non-scarring blistering of the skin, mild skin atrophy, hypodontia and dental caries. Light microscopy showed subepidermal blistering. Direct immunofluorescence was negative. On indirect immunofluorescence staining of a fresh spontaneous blister, bullous pemphigoid antigen and laminin were localized to the blister roof, and collagen IV and collagen VII to the blister base, indicating junctional splitting. Electron microscopy revealed a normal dermo-epidermal junction zone, including normal hemidesmosomes. There were no deposits of electron-dense amorphous material.  相似文献   

18.
19.
BACKGROUND: Sera from patients with atrophic corpus gastritis with pernicious anemia frequently contain parietal cell autoantibodies. We have previously demonstrated that the human H,K-adenosine triphosphatase (H,K-ATPase) alpha-subunit constitutes a major autoantigen. The present study investigates whether the human H,K-ATPase beta-subunit is an autoantigen, too, METHODS: The gene of the human beta-subunit was expressed in insect cells by a baculovirus expression system. The reactivity of sera from 42 patients towards the recombinant glycoprotein was analyzed by means of an enzyme-linked immunosorbent assay. RESULTS: Thirty-nine of the 42 sera (93%) scored positive. Autoantibody binding in 41 sera (98%) was eliminated when unglycosylated beta-subunit was used as antigen, and antibody binding in the last serum was decreased by 30%. CONCLUSIONS: The results indicate that the beta-subunit is indeed a major autoantigen and that carbohydrates are involved in binding of the autoantibodies.  相似文献   

20.
We have previously shown that the 180 kDa bullous pemphigoid antigen (BPAG2) is distributed on the lateral-apical (as a pool) and ventral (as hemidesmosomes) cell membranes of monolayer cultured keratinocytes and that addition of IgG purified from bullous pemphigoid (BP) patients (BP-IgG) causes the internalization of immune complexes of BPAG2 and BP-IgG from the lateral-apical cell membrane. This internalization of BPAG2 is believed to inhibit the Ca2+ induced reformation of hemidesmosomes on the ventral cell membrane, possibly by inhibiting the supply of the antigen from the lateral-apical to the ventral membranes to form hemidesmosomes. The purpose of this paper is to examine, by using biopsy specimens from BP patients (12 cases), whether or not this internalization of BPAG2 is generated in situ. The fates of BPAG2, 230 kDa BPA (BPAG1) and bound BP-IgG were traced by immunofluorescence microscopy using monoclonal antibodies to BPAG1, BPAG2 and human IgG. In more than half of the lesional and perilesional biopsy specimens, internalization of BPAG2 into the basal cells was observed, while in normal skin BPAG2 was detected on the whole surface of the basal cells without its internalization. No internalization of BPAG1 was detected in BP and normal epidermis. These results suggest that binding of BP-IgG on the lateral-apical cell surface of basal cells causes internalization of BPAG2 in situ in the epidermis of BP patients similar to that seen in cultured cell systems, and that this internalization of immune complexes of BPAG2 and BP-IgG may play an important part in blister formation in BP.  相似文献   

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