Characterization of an autoantigen associated with chronic ulcerative stomatitis: the CUSP autoantigen is a member of the p53 family.

A unique clinical syndrome has been described in which patients have chronic oral ulceration and autoantibodies to nuclei of stratified squamous epithelium. We have characterized the autoantibodies from patients sera and found that the major autoantigen is a 70 kDa epithelial nuclear protein. Sequencing of the cDNA for this protein, chronic ulcerative stomatitis protein, revealed it to be homologous to the p53 tumor suppressor and to the p73 putative tumor suppressor, and to be a splicing variant of the KET gene. The p53-like genes, p73 and the several KET splicing variants, are recently described genes of uncertain biologic and pathologic significance. This study provides the first clear association of a p53-like protein with a disease process.

Desmoglein 1 and desmoglein 3 are the target autoantigens in herpetiform pemphigus.

OBJECTIVE: To determine the cell surface autoimmune target of herpetiform pemphigus (HP). DESIGN: Serum samples of HP were examined by immunoblot studies with human epidermal extracts, enzyme-linked immunosorbent assay with baculovirus-expressed recombinant desmoglein (rDsg) 1 and rDsg3, and immunoadsorption assay with rDsg. PATIENTS: Twenty serum samples were obtained from patients with HP who have typical clinical and histological features. All serum samples showed positive staining against keratinocyte cell surfaces by indirect immunofluorescence studies with healthy human skin. RESULTS: Immunoblot results showed that of 17 HP serum samples, only 5 reacted with a 160-kd band and 1 reacted with a 130-kd band. Results of enzyme-linked immunosorbent assays with rDsg1 and rDsg3 demonstrated that of 20 HP serum samples, 16 were positive against Dsg1 and 4 were positive against Dsg3. No serum samples reacted with both. Furthermore, in 19 of 20 HP serum samples, immunoreactivity against keratinocyte cell surfaces was completely removed by preincubation with rDsg1 and rDsg3 as shown by indirect immunofluorescence, excluding a possibility that these HP sera contain autoantibodies against other cell surface molecules. CONCLUSIONS: Dsg1 and Dsg3 are the major cell surface target molecules of HP, suggesting that most cases of HP are clinical variants of pemphigus foliaceus and that the rest might be variants of pemphigus vulgaris.

Novel non-radioisotope immunoprecipitation studies indicate involvement of pemphigus vulgaris antigen in paraneoplastic pemphigus.

We have developed two different novel immunoprecipitation assays in which radioisotopes are not used, and have examined antigens for four cases of paraneoplastic pemphigus (PNP) including three new patients. The PNP sera showed a clear reactivity with transitional epithelia of rat urinary bladder by immunofluorescence, and reacted with a characteristic doublet of the 210 and 190 kD proteins by immunoblotting of normal human epidermal extract, confirming the diagnosis of PNP. In addition, by immunoprecipitation using silver-stain to detect immunoprecipitated proteins, the PNP sera detected the 250, 210 and 190 kD proteins, while control bullous pemphigoid sera detected only the 230 kD bullous pemphigoid antigen. Furthermore, with another immunoprecipitation using cell surface biotinylation, three of the four PNP sera specifically reacted with the 130 kD pemphigus vulgaris antigen (Dsg3), indicating that pemphigus vulgaris antigen may be involved in PNP. This reactivity was further suggested by the immunoblot analysis using recombinant pemphigus vulgaris antigen. In future, these non-radioisotope immunoprecipitation assays should become a useful tool not only to unravel the complex situation for the PNP antigens, but also to study antigens in other autoimmune bullous skin diseases.

Is chronic ulcerative stomatitis an entity? Clinical and immunological findings in 18 cases.

Chronic ulcerative stomatitis (CUS), a rare disease of oral mucosa found to be associated with unusual antinuclear antibodies reactive exclusively with squamous epithelia (squamous epithelium-specific antinuclear antibodies - SES-ANA), has been reported to occur almost exclusively in older females and to respond dramatically to antimalarials. We report on a large series of 18 cases positive for SES-ANA, 15 of them with active CUS, followed-up for several years. We found that the disease may occur, although rarely, in men and younger females. The antibodies persist after clearance of mucosal lesions, are fixed in vivo and also in uninvolved skin and other mucosa, and may occur in patients without CUS. Thus their pathogenic potential remains to be established. We also describe some unusual cases of CUS, one associated with cicatricial conjunctivitis, another associated with gluten-sensitive enteropathy and bizarre skin lesions, and 3 cases associated with lichen planus (LP) or LP-like lesions. The antimalarials, initially highly effective, even for several months or years, not infrequently proved to be insufficient and the relapses responded usually only to combined therapy with chloroquine and small doses of corticosteroids. SES-ANA antibodies are quite specific and present an immunologic marker of this unusual autoimmune disease.

Familial pemphigus vulgaris in mother and daughter.

BACKGROUND: Pemphigus vulgaris is an autoimmune disease in which genetics appears to be of basic importance. Although association with certain human leukocyte antigen (HLA) alleles has been found in some ethnic groups and individuals, no true disease susceptibility genes have been established, and familial cases are very unusual. METHODS: We report a Polish family with pemphigus vulgaris in the mother and daughter. The diagnosis was confirmed by cytologic, histologic, and immunofluorescence studies. RESULTS: The course was severe and the disease long-lasting in the mother, probably due to treatment with small doses of corticosteroids without immunosuppressive drugs. In the daughter, treated with larger doses of corticosteroids and azathioprine, the lesions regressed within 4 months, after which maintenance therapy was instituted with 10 mg of prednisone daily. The HLA studies performed in the daughter and her three children after the mother had died showed identical haplotypes in both the patient and the healthy children. The patient has given birth to a healthy child while still having a high titer of intercellular (IC) antibodies. CONCLUSIONS: The familial occurrence of pemphigus in first-degree relatives is suggestive of inherited susceptibility to the disease, transmitted as a dominant trait. The identical haplotypes in the healthy children of the patient favor the role of other, unknown factors required for the development of the disease in predisposed individuals.

Analysis of antigens recognized by autoantibodies in herpes gestationis. Usefulness of immunoblotting using a fusion protein representing an extracellular domain of the 180 kD bullous pemphigoid antigen.

Herpes gestationis (HG) is a rare pregnancy-associated disease. The aim of this study was to compare various immunohistochemical and immunobiochemical techniques with respect to their diagnostic sensitivity for HG. We studied 43 HG sera; only half of these reacted with the basement membrane zone (BMZ) with both indirect immunofluorescence (IF) and complement IF of normal human skin. 81% of the sera reacted with the epidermal side of 1 M NaCl-split skin. In general, titers of anti-BMZ antibodies in HG sera were lower than those in bullous pemphigoid (BP) sera. Immunoblot analysis of human epidermal extracts showed that 51% of HG sera recognized the 180 kD BP antigen (BP180) and 26% recognized the 230 kD BP antigen (BP230). We also studied the reactivity of HG sera with fusion proteins representing either the NC16a domain of human BP180 or the C-terminal region of mouse BP230. Whereas 79% of HG sera reacted with the BP180 fusion protein, only 5% recognized the BP230 fusion protein. Our results suggest that indirect IF of 1 M NaCl-split skin and immunoblotting of a fusion protein representing the BP180 NC16a domain are more sensitive techniques for the diagnosis of HG than conventional and complement IF or immunoblotting of crude epidermal extracts.

IgA antibodies in chronic bullous disease of childhood react with 97 kDa basement membrane zone protein.

Chronic bullous disease of childhood (CBDC) is an autoimmune blistering disease occurring in prepubertal children. Both CBDC and its adult counter-part, linear IgA bullous dermatosis (LABD), are characterized by linear deposition of IgA along the cutaneous basement membrane zone (BMZ). Circulating IgA antibody in LABD has been found to bind to a 97-kDa BMZ antigen, whereas the antigen in CBDC has not been well characterized. The purpose of this study was to evaluate the immunoreactivity of BMZ IgA antibodies in a series of CBDC patients. We evaluated 12 sera from patients with CBDC with circulating IgA anti-BMZ antibodies on indirect immunofluorescence (IIF), which stained the epidermal side of split skin with titers ranging from 1:20 to 1:640. Immunoblotting was performed against two preparations of BMZ proteins: one enriched with the two bullous pemphigoid antigens (BP230, BP180) and one enriched with the LABD antigen (LABD97). Eight of the twelve sera reacted with a 97-kDa protein that co-migrated with the protein detected in many LABD sera. The intensity of the reaction on immunoblot correlated with serum antibody titers. There was no consistent pattern of reactivity of the IgA anti-BMZ antibodies with either the BP230 or BP180 antigens, although two sera reacted with several higher molecular mass proteins (160-200 kDa). The significance of this reactivity was examined with immunoblotting using BMZ-affinity-purified antibodies, and ELF using nitrocellulose-eluted antibodies. One serum also contained anti-BMZ IgA antibodies that reacted with a 180-kDa protein, corresponding to BP180. We conclude that IgA antibodies in CBDC sera recognize a 97-kDa BMZ antigen present on the epidermal side of BMZ split skin that co-migrates with the antigen previously identified in LABD. These findings suggest that CBDC and LABD are the immunologically related disorders occurring in different age groups.

Chronic ulcerative stomatitis with stratified epithelium-specific antinuclear antibodies.

BACKGROUND: In 1990 a new disease-associated antinuclear antibody was first recognized as a specific immunologic marker for a chronic form of ulcerative stomatitis (CUS). METHODS: Another case is reported herein and the subject of chronic ulcerative stomatitis with stratified epithelium-specific antinuclear antibodies (SES-ANA) is reviewed. Intraoral biopsies from this patient were submitted for microscopic examination and direct immunofluorescence. Indirect immunofluorescence studies were also performed. Serial SES-ANA titers were obtained with the patient on maintenance treatment with hydroxychloroquine. A skin biopsy of a recent lichenoid eruption was obtained and skin explants grown in the serum of this patient were studied in tissue culture with reference to SES-ANA binding and complement fixation. RESULTS: Biopsy and serum studies confirmed a diagnosis of CUS with SES-ANA in the patient reported. Skin biopsy showed lichen planus. The patient was treated with hydroxychloroquine with a favorable response. Serial SES-ANA titers did not parallel the disease activity. Among the substantive observations made from skin explants cultured in the serum of this patient was widespread fixation of C3 to the nuclei of basal cells. CONCLUSIONS: The case described herein extends the findings in CUS to include lichenoid skin lesions. Records show that at least four of 11 cases of CUS had skin lesions, whereas all had oral lesions. Stratified epithelium-specific antinuclear antibodies serve as the key marker of CUS. Skin explants grown in the serum of this CUS patient bind SES-ANA in tissue culture. Sections of explants fix complement. Titers of SES-ANA have been reported to parallel disease activity in one case, but not in the present case. Thus, there appears to be case-to-case variation. The treatment of choice for CUS is hydroxychloroquine.

Significance of IgG-subclass antibody determinations in bullous pemphigoid.

The presence of circulating basement membrane zone (BMZ) antibodies is characteristic of patients with bullous pemphigoid (BP) and are routinely employed in making the diagnosis. The positive tests, however, occur in 50-70% of patients with BP, thus necessitating consideration of other tests in a significant number of patients. The purpose of this study was to examine the efficacy of indirect immunofluorescence (IF) tests specific for various IgG subclasses antibodies to BMZ in BP, especially in patients who are seronegative on routine indirect IF tests with fluorescein-conjugated antibodies to IgG. BMZ antibodies primarily are of IgG4 subclass and are present in all BMZ antibody positive BP cases. Of BP patients negative for BMZ antibodies, 72% were found positive when tested for IgG4 subclass antibodies. In conclusion, testing for IgG4 subclass BMZ antibodies enhances the sensitivity of serum tests from 68.5% to 91%. This may be due in part to the inherent increased sensitivity of the assay and for detecting subclasses of IgG and in part, due to the subclass distribution of the BP antibodies.

Characterization of paraneoplastic pemphigus autoantigens by immunoblot analysis.

We investigated the antigen molecules for six clinically typical cases of paraneoplastic pemphigus (PNP) using immunofluorescence, immunoprecipitation, and immunoblotting. All the PNP sera showed a clear reactivity with transitional epithelia of rat urinary bladder and immunoprecipitated the 250-kD, 230-kD, 210-kD, 190-kD, and 170-kD proteins in various combinations, confirming the diagnosis of PNP. Immunoblot analysis demonstrated slightly different reactivity from that of immunoprecipitation. With immunoblotting of normal human epidermal extract, bovine desmosome preparation, and extract of cultured squamous cell carcinoma cells, all the PNP sera reacted with a characteristic doublet of the 210-kD and 190-kD proteins. However, immunoblotting detected the 250-kD desmoplakin I and the 230-kD bullous pemphigoid antigen less frequently and did not detect the 170-kD protein. Further immunoblot studies indicated that the 210-kD protein is different from desmoplakin II and that the 190-kD protein is most frequently detected by PNP sera. Two of the six PNP sera specifically reacted with the extracellular domain of recombinant pemphigus vulgaris antigen protein, indicating that pemphigus vulgaris antigen may be involved in PNP. In future studies to unravel the complex mechanisms of the PNP antigens, the immunoblot technique may be a useful tool.

Immunogold localization of the 97-kD antigen of linear IgA bullous dermatosis (LABD) detected with patients' sera.

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.

Unusual acantholytic bullous dermatosis associated with neoplasia and IgG and IgA antibodies against bovine desmocollins I and II.

There are unusual cases of pemphigus that have antibodies nonreactive with either pemphigus vulgaris or pemphigus foliaceus antigens. We describe a patient with an acantholytic bullous dermatosis and lung cancer with intercellular IgG and IgA antibodies that differed in specificity from those of pemphigus vulgaris and pemphigus foliaceus and reacted with bovine desmocollins I and II and recombinant desmocollin protein.

Preliminary, dermatologic first step criteria for lupus erythematosus and second step criteria for systemic lupus erythematosus.

BACKGROUND: Comparisons of cases of systemic lupus erythematosus (SLE) with cases of rheumatoid arthritis and other rheumatologic disorders affords the basis of the 1982 revised criteria of the American Rheumatism Association (ARA) for classifying SLE cases. We address three questions: Do comparisons of LE cases with non-LE cases that have suggestive skin lesions yield criteria for use in dermatology clinics for primary classification of cases with photo distributions of skin lesions? Do comparisons of SLE with cutaneous LE cases yield the same or similar criteria to the revised ARA criteria for SLE? How should subacute cutaneous LE cases be evaluated for signs of significant systemic involvement? METHODS: Discriminant analyses on 168 cases with skin lesions suggestive of LE were performed using data based on the ARA criteria for SLE and study factors for cutaneous LE suggested by the European Academy of Dermatology and Venereology. RESULTS: These yielded two sets of criteria: (1) The 11 preliminary, dermatologic first step criteria (10 plus 1 for discoid lesions and histology) serve to classify cases as LE or non-LE. (2) The 11 preliminary, dermatologic second step criteria classify LE cases as cutaneous LE or systemic LE. Interestingly, 5 of 11 of these second step criteria differ from the 11 ARA criteria for systemic LE. These second step criteria afford a useful means of distinguishing between subacute cutaneous LE cases with or without significant systemic involvement. CONCLUSIONS: The study factors included in both the first and the second step criteria fall into three groups, notably clinical criteria, laboratory criteria, and "added study factors." The latter factors distinguish between the groups compared (LE vs. non-LE and cutaneous vs. systemic LE) but not as well as the study factors included as "criteria."

Erythema annulare-like acantholytic dermatosis (EAAD): nonbullous pemphigus or a new entity?

This article describes a case of unusual annular erythema-like dermatosis, with histological features of pemphigus foliaceus (subcorneal acantholysis) and IgG antibodies in circulation and bound in vivo to the keratinocyte surface. The reactivity of the antibodies, restricted to human squamous epithelium, was unique, differing from that of all known forms of pemphigus. This also was confirmed by immunoprecipitation. The problem is that these circulating antibodies could be missed if not determined on human substrate. It is to be established whether such cases present a new type of pemphigus or a unknown dermatosis with an autoimmune response of a pemphigus type.