外用0．1％氨甲蝶呤霜治疗银屑病54例

５４例顽固性斑块型银屑病患者外用０．１％氨甲蝶呤霜随机自体双盲对照治疗６周，同时用高效液相色谱法作血清ＭＴＸ浓度监测。结果：ＭＴＸ霜组有效率８３．３％（对照组３７．０％）、显效率４８．１％（对照组９．３％）、治愈率７．４％（对照组０）。血清中未测得ＭＴＸ。未见明显全身副作用。结果表明外用０．１％氨甲蝶呤霜治疗银屑病有效。     

Serological tests for syphilis in Saudi Arabia.

A total of 6684 sera were initially screened for syphilis by the Venereal Disease Research Laboratory (VDRL) test and the Treponema pallidum haemagglutination assay (TPHA). Reactive sera from either or both these tests were tested for confirmation by the fluorescent treponemal antibody-absorbed (FTA-ABS) test. VDRL biological false positive reactors were detected in 0.5% of the total sera examined, with 0.4% and 0.8%, respectively, obtained in pregnant women and blood donors. Eight sera (0.1%) were found to be positive in the TPHA test alone. An overall positivity of 2.7% for syphilis was detected, with a 0.85% positivity in antenatal patients. Infection with T pallidum seemed to be more common in men than in women (1.6:1) and predominated in the age group 20-39 years. Serological testing of sera from 26 mother and infant pairs allowed one case of congenital syphilis to be detected by FTA-ABS (IgM) and identified VDRL biological false positivity in seven infants.     

Cicatricial pemphigoid antigen differs from bullous pemphigoid antigen by its exclusive extracellular localization: a study by indirect immunoelectronmicroscopy

Several components of the dermal-epidermal junction (DEJ) bear the name of the autoimmune bullous disease in which they are involved. The epidermolysis bullosa acquisita (EBA) antigen, a component of anchoring fibrils, and the bullous pemphigoid (BP) antigen, a component of hemidesmosomes (HD) with a molecular weight of 220-240 kD, have been well characterized. In contrast, there is little data known about the cicatricial pemphigoid (CP) antigen. No differences between CP and BP have been reported when sera of patients were studied by Western immunoblotting. Findings of a study of sera from 8 patients with CP by indirect immunoelectron microscopy (IEM) on normal human skin are reported. Saponin (0.1% 10 mn) was used as a permeabilizing agent of cytomembranes and saponin-treated skin samples were compared to saponin-untreated skin samples. Four sera from patients with BP, one from a patient with EBA, and three from healthy donors served as controls. The CP sera produced a similar staining of DEJ on both saponin-treated and saponin-untreated skin samples: immune deposits were localized over the lamina densa and the lower part of the lamina lucida clearly separated from the cytoplasmic membrane of keratinocytes, in regularly spaced clumps. The BP sera produced an intense staining of DEJ only on saponin-treated skin samples: immune deposits were observed on the cytoplasmic attachment plaque of the HD; on saponin-untreated skin samples, BP sera produced only a faint staining of the extracellular part of HD. Finally, as expected the EBA serum appeared on the lower part of the lamina densa and anchoring fibrils, and no DAB deposits were observed with the serum of healthy donors. This data indicated that CP antigen is different than BP antigen by its exclusive extracellular localization. It may be a component of anchoring filaments.     

CH50 and C3 Component of Complement in Hansen''s Disease

Although a variety of complement values have been reported in leprosy, we found no difference in the CH50 and C3 in the sera of 30 normal persons and 233 lepromatous patients. No statistically significant difference was observed in CH50 and C3 values between healthy controls and lepromatous patients taken as a whole or separated into the different types of the disease spectrum (P greater than 0.1). A statistical difference in C3 titers was found between health controls and borderline patients (P less than 0.05 greater than 0.01) but the sample number is too small to be valid. An important number of sera tested had low and an equally important number had high complement values. Sera with high and low values are important because high values are found in acute inflammatory reactions and low values demonstrate complement activation. Discrepancies in reported results are probably due not only to differences in the methods used, storage and limited number of sera tested, but mainly to the stage of the disease and the drug's administration.     

Isolation of an acidic polysaccharide antigen from Propionibacterium acnes

Summary An acidic polysaccharide antigen is released from Propionibacterium acnes I and II during growth. The molecular weight of the antigen was heterogeneous and when fractionated on a Sepharose CL-6B column, the antigen was detected at K _av values of between 0.1 and 1.0. The pI of the antigen was below 3.5. Rabbit antiserum raised against purified acidic-polysaccharide agglutinated P. acnes showing that the polysaccharide was a surface antigen. Human antibodies towards whole P. acnes-II organisms were quantitated by an agglutination technique, and antibodies towards purified acidic polysaccharide were quantitated by single radial immunodiffusion. A high prevalence of antibodies against whole bacteria and the acidic polysaccharide was found in sera from healthy individuals. The antibody titre in sera from acne patients was significantly higher than that in sera from blood donors.     

IgA class antibodies in dermatitis herpetiformis: reaction with tissue antigens

The mechanism for deposition of IgA in dermatitis herpetiformis (DH) remains unclear. To test the hypothesis that a circulating IgA class antibody in DH patients binds to constituents of normal human skin, we employed the highly sensitive methods of immunoblotting and indirect immunofluorescence. Sera from 64 DH patients, 67 randomly selected normal control subjects, 29 histocompatibility locus antigen (HLA) B8/DR3/DQw2 controls, and 12 psoriatic patients were tested for IgA binding to various substrates, including dermal and epidermal extracts, fibroblast and keratinocyte supernatants, monkey esophagus sections, and whole and saline-split normal human skin sections. Significant differences observed among the groups in the frequency of detectable IgA antibodies reacting with various substrates were as follows: 1) IgA antibodies in 30% of both DH and HLA B8/DR3/DQw2 sera bound to a 60-Kd protein in dermal extracts (p less than 0.25 versus non-HLA matched controls); 2) IgA antiendomysial antibodies were present in 38% of DH patients (predominantly those not on gluten-free diets), whereas both normal control groups had frequencies of 5-10% (p less than 0.025); 3) there was more nonspecific IgA antibody-binding to dermal, epidermal, and bovine proteins in DH and HLA control sera than in normal sera; and 4) IgA antibodies directed against the basement membrane were present with an increased frequency of 25% in both DH and HLA B8/DR3/DQw2 sera (p less than 0.1 versus non-HLA matched controls). Therefore, these results do not support the hypothesis that there is an unique antigen within normal human skin to which IgA antibodies from DH sera bind.     

Skin fibroblast activity in pretibial myxoedema and the effect of octreotide (Sandostatin®) in vitro

The accumulation of glycosaminoglycans in the skin in pretibial myxoedema appears to be a response by local fibroblasts to a stimulating factor in the patient's serum, but the identity of the factor, its ability to stimulate skin fibroblasts as opposed to cultured thyroid cells, and the specificity of its effect to pretibial skin fibroblasts, are all controversial. We have studied fibroblasts cultured from the lesional skin of two women with pretibial myxoedema, and compared their proliferation and secretion of glycosaminoglycans with those of fibroblasts from the patients' forearms and from the forearm skin of two normal subjects. We found that in the presence of the patients' sera all six lines of fibroblasts secreted more glycosaminoglycans [205±21% (SD)] than with normal human sera (147±19%), or fetal calf serum (100%). Fibroblast proliferation showed the same pattern of differences: patients' sera 142±22%; normal human sera 116±9%, and fetal calf serum 100%. These experiments confirm the presence of a serum factor in pretibial myxoedema which is capable of stimulating the activity of skin fibroblasts in vitro, and show that its effects are not restricted to fibroblasts from pretibial skin or to those grown from the skin of the patients. Proliferation of normal fibroblasts cultured in medium supplemented with fetal calf serum was reduced by Sandostatin® (octreotide), but it failed to inhibit their secretion of glycosaminoglycans. In contrast, secretion of glycosaminoglycans by a patient's pretibial skin fibroblasts was almost completely inhibited by 1 mM minoxidil. In the presence of patients' sera Sandostatin® (0.1–10 μg/ml) reduced secretion of glycosaminoglycans by about 50%. Our data support the use of Sandostatin® in pretibial myxoedema, and suggest that it may suppress fibroblast glycosaminogly- can secretion within the skin via depletion of insulin-like growth factor or the blocking of its effect.     

Antibody titers to Propionibacterium acnes cell wall carbohydrate in nodulocystic acne patients

In order to determine which structures in Propionibacterium acnes are most antigenic to severe acne patients, we studied the specificity of anti-P. acnes antibodies in serum from 15 nodulocystic acne patients and 5 normals. Complement fixation titers to P. acnes cell wall fractions were determined using guinea pig serum as a complement source. The mean titers of patients and normals to whole cells were 39.6 and 3 (p less than 0.1); to crude cell wall, 138 and 8 (p less than 0.01); and to protein and nucleic acid-free cell wall, 225 and 9.33 (p less than 0.001), respectively. The mean precipitin titer to P. acnes cytosol was 12.7 for patients and 0 for normals. Immunoelectrophoresis of cytosol from 8 P. acnes strains were developed with each of the 15 patient sera. A single broadly migrating anionic antigen was detected. The antigen was also present in P. acnes culture supernatants. Sephadex G-100 chromatography of cytosol revealed a single peak of antigenic reactivity at Mr = 100,000. Three patients' sera revealed a second weakly reacting antigen in the cytosol preparation. Twentyfold concentration of immunoglobulin from patient sera failed to reveal any other antigenic reactivities. The antigen was found to be resistant to nuclease, pronase, and lysozyme treatment; was precipitable with 70% ethanol; and was destroyed by sodium m-periodate--findings that are consistent with a carbohydrate structure.     

Effect of Nonenzymatic Glycosylation on the Titers of Circulating Autoantibodies in Pemphigus and Pemphigoid

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°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, SΔ1 and 4575. All BP sera reacted with SΔ1, and 5 out of 10 BP sera reacted with both SΔ1 and 4575. In all the sera that reacted only with SΔ1, the glycosylated sera showed a 1 doubling dilution decrease in autoantibody titer. Interestingly, in 4 out of 5 sera that reacted with both SΔ1 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.     

Antigenic specificity of fogo selvagem autoantibodies is similar to North American pemphigus foliaceus and distinct from pemphigus vulgaris autoantibodies

Fogo selvagem (FS) is clinically, histologically, and immunopathologically similar to sporadic pemphigus foliaceus (PF, as seen in North America and Europe), although the epidemiology of these 2 diseases differs markedly. It has been proposed that FS is identical to PF but, for some reason, occurs in an endemic focus in central Brazil. If this hypothesis is correct, the autoantibodies in FS and PF should have similar antigenic specificities. We studied sera from 13 patients with FS from central Brazil, and compared them with 20 sera from patients with PF from the United States. All these sera had circulating antibodies that bound the cell surface of epithelial cells in identical patterns by indirect immunofluorescence on monkey esophagus or normal human skin. In immunoprecipitation studies none of the 13 FS sera precipitated the pemphigus vulgaris (PV) antigen from radiolabeled extracts of cultured human keratinocytes. This is similar to the findings with PF sera of which 19 of 20 sera did not react with PV antigen, but in sharp contrast to the results with PV sera which, as previously reported, all immunoprecipitate the PV antigen. Immunoblotting performed on extracts of normal human epidermis demonstrated that 7 of 20 PF sera specifically and intensely bound an approximately 160 kD polypeptide, previously identified as desmoglein I, a desmosomal glycoprotein. Similarly, 3 of 13 FS sera specifically bound a 160 kD polypeptide. Thirteen normal sera from North America, 8 normal and disease control sera from central Brazil, 11 PV sera, and 12 bullous pemphigoid sera did not specifically bind this polypeptide. Two-dimensional gel electrophoresis confirmed that the 160 kD polypeptides identified by the subgroup of PF and FS sera were identical. These studies demonstrate that, although the exact molecular specificities of the majority of PF and FS sera remain to be determined, FS autoantibodies do not bind the PV antigen and a subgroup of FS autoantibodies have molecular specificity identical to that of a subgroup of PF autoantibodies.     

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.     

Interferon in rabbit sera after inoculation with Treponema pallidum suspensions contaminated with PED virus

Paired rabbits sera were examined for the presence of interferon and pathogenicity for rabbits. The sera were obtained before and 48 hours after inoculation with Treponema pallidum suspensions of rabbit origin in 12 selected laboratories. Classical interferon, detectable in dilutions from 1/9 to 1/81, were found in 27 out of 39 postinoculation sera from which the pleural effusion disease (PED) virus was isolated. Serum interferon was not detectable in dilutions greater than or equal to 1/9 in 16 virus-negative postinoculation sera or in any of the 55 preinoculation sera. Interferon was found more often in sera from which highly virulent strains of PED virus were isolated than in sera from which strains of low virulence were isolated. The serum interferon assay provides useful presumptive evidence of contamination of rabbit-passaged treponemes with PED virus, but the assay is least useful when PED virus is present subclinically.     

Interferon in rabbit sera after inoculation with Treponema pallidum suspensions contaminated with PED virus.

Paired rabbits sera were examined for the presence of interferon and pathogenicity for rabbits. The sera were obtained before and 48 hours after inoculation with Treponema pallidum suspensions of rabbit origin in 12 selected laboratories. Classical interferon, detectable in dilutions from 1/9 to 1/81, were found in 27 out of 39 postinoculation sera from which the pleural effusion disease (PED) virus was isolated. Serum interferon was not detectable in dilutions greater than or equal to 1/9 in 16 virus-negative postinoculation sera or in any of the 55 preinoculation sera. Interferon was found more often in sera from which highly virulent strains of PED virus were isolated than in sera from which strains of low virulence were isolated. The serum interferon assay provides useful presumptive evidence of contamination of rabbit-passaged treponemes with PED virus, but the assay is least useful when PED virus is present subclinically.     

Comparative study of autoantigens for various bullous skin diseases by immunoblotting using different dermo-epidermal separation techniques

We investigaged the reactivity of pemphigus vulgaris (PV), pemphigus vegetans, pemphigus foliaceus (Pf), Brazilian Pf, bullous pemphigoid (BP), and epidermolysis bullosa acquisita (EBA) sera with an immunoblot analysis using human epidermal and dermal extracts as a source of antigen. To obtain epidermal and dermal extracts three different dermo-epidermal separation methods were used: namely, ethylenediaminetetraacetic acid (EDTA) separation, heat separation, and dispase separation. All the 15PV and the seven pemphigus vegetans sera demonstrated a 130-kDa PV antigen in epidermal extracts obtained by all the three methods. Furthermore, three PV sera also showed a 160-kDa Pf antigen, desmoglein. Ten of 14 Pf sera and six of 15 Brazilian Pf sera reacted with desmoglein in the same pattern in all the three epidermal extracts. Fifteen of the 22 BP sera showed reactivity with 230-kDa BP antigen in the same pattern in all the three epidermal extracts, whereas 14 BP sera delected the 180-kDa BP antigen in extracts of EDTA-and heat-separated epidermis but not in dispase-separated epidermal extract. Dermal extracts were obtained by EDTA- and heat-separated dermis, and all six EBA sera labelled a 290-kDa EBA antigen in both samples. These results suggest that heat-separated skin is as useful as EDTA-separated skin for detecting various autoantigens, but heat separation is preferable because the preparation time is shorter.     

Evidence for immunologic mechanisms in human vitiligo: patients' sera induce damage to human melanocytes in vitro by complement-mediated damage and antibody-dependent cellular cytotoxicity

Human vitiligo is a common depigmenting disorder that is often associated with polyendocrinopathies. The etiology of vitiligo is unknown although there is indirect evidence of a strong association between antimelanocyte antibodies in animal and human vitiligo. We report direct evidence that vitiligo patients' sera containing antimelanocyte antibodies can lyse cultured human melanocytes by both complement activation and antibody-dependent cellular cytotoxicity (ADCC). Melanocyte cytotoxicity was measured using an ethidium bromide/acridine orange viability assay, after 4 and 16 h incubation with sera from vitiligo patients and from normal controls. Significant melanocyte cytotoxicity was seen with vitiligo patients' sera as an antibody source with both complement-mediated cytotoxicity (p less than 0.01) and ADCC (p less than 0.05) as effector mechanisms. Nine of 11 vitiligo patients' sera produced cytotoxicity by complement-mediated lysis or ADCC. No cytotoxicity was seen using fibroblast targets and vitiligo patients' sera. The lysis of human melanocytes by vitiligo patients' sera by two different effector mechanisms provides direct support for the autoimmune hypothesis of human vitiligo.     

DNA-binding proteins in the sera of patients with malignant melanoma

Sera of patients with various malignancies are known to contain DNA-binding proteins (DBP) which are not present in sera of normal individuals. In this paper sera of patients with malignant melanoma (MM) were examined as to whether characteristic DBP are present, too. DBP are isolated by DNA-affinity chromatography and represent 0.5-0.9% of all serum proteins. After separation of the DBP by SDS slab gel electrophoresis no typical DBP is detectable in sera of MM-patients. However, quantitative differences are found in sera of patients in the clinical stages I-III and/or tumor level 3-5: 1. All 9 sera of patients who had clinical signs of MM contain more DBP with molecular weight (mw) of 20,000-24,000 dalton than control sera. However, these DBP are only increased in 30% of the 22 sera from MM-patients who had clinical signs for 13-73 months after tumor excision. 2. All sera of the 10 MM-patients of whom sera were drawn twice after tumor excision at an interval of 7-46 months without clinical signs, showed a reduction of DBP with mw 30,000, 68,000, and 165,000.     

The major cicatricial pemphigoid antigen is a 180-kD protein that shows immunologic cross-reactivities with the bullous pemphigoid antigen.

Recent studies have shown that sera from patients with cicatricial pemphigoid (CP) contained autoantibodies against epidermal antigens of molecular weight 230 kD and/or 180 kD by immunoblotting, similar to those recognized by bullous pemphigoid (BP) sera. Previous immunoprecipitation studies have shown that BP sera only precipitated the 230-kD antigen. To characterize the CP antigen(s) we tested 10 CP sera, 10 BP sera, and four controls by both immunoprecipitation of radiolabeled cells and immunoblotting of epidermal extracts. For immunoprecipitation, we used 0.5% NP-40 extracts of both normal human keratinocytes and Pam cells. All CP sera precipitated a 180-kD protein that co-migrated with the BP180 antigen precipitated by some individual BP sera. Two of these CP sera also faintly bound a 230-kD protein of similar molecular weight as the major BP230 antigen. CP and BP sera with an immunoblotting pattern of 180 kD immunoprecipitated a co-migrating 180-kD protein. CP sera reacting by immunoblotting with the 230-kD antigen precipitated the 180-kD and/or the 230-kD antigen. In contrast, BP sera reacting with the 230-kD antigen only precipitated this antigen. In further experiments, labeled 0.5% NP-40 extracts from Pam cells were first preabsorbed with a reference BP serum and then immunoprecipitated with CP sera. Under these conditions, CP sera that immunoprecipitated both 180-kD and 230-kD proteins with the standard procedure no longer precipitated these proteins. Our results suggest that a 180-kD protein is the major CP target-antigen that demonstrated immunologic cross-reactivities with the BP180 and the BP230 antigens.     

Antigen specificity in subsets of mucous membrane pemphigoid

Mucous membrane pemphigoid (MMP) has several subsets based on target antigens recognized by their sera. MMP and ocular cicatricial pemphigoid (OCP) sera recognize beta4 integrin subunit, oral pemphigoid sera recognize alpha6 integrin subunit, and anti-epiligrin cicatricial pemphigoid sera recognize laminin 5. Our aim is to determine if autoantibodies in the sera of patients with MMP, OCP, and oral pemphigoid (OP) recognize only their target antigens, and to see if this specificity is maintained throughout the clinical course. An immunoblot assay using bovine gingival lysate was used as substrate. Fifteen MMP patients, eight with OCP, and 15 OP patients were studied before therapy and at multiple intervals during the clinical course. Absorption and blocking studies were performed to determine binding specificity. Sera of patients with MMP and OCP recognize only beta4 integrin subunit, and sera of OP patients recognize alpha6 integrin throughout the clinical course. The sera of patients in the subsets of MMP described in this report show adherence and selectivity to target antigen during the entire clinical course, without crossover, interaction, or change. Hence, these subsets of MMP provide an excellent model to study clinical correlation with antigen and antibody specificity, in autoimmunity.     

Usefulness of enzyme-linked immunosorbent assay using recombinant desmogleins 1 and 3 for serodiagnosis of pemphigus

Pemphigus is an autoimmune blistering disease with two major subtypes, pemphigus vulgaris (PV) and pemphigus foliaceus (PF). Patients with pemphigus have circulating antidesmoglein (Dsg)1 and/or anti-Dsg3 IgG autoantibodies. We have previously developed enzyme-linked immunosorbent assays (ELISAs) using recombinant Dsg1 and Dsg3 expressed by baculovirus as a diagnostic tool for pemphigus. The purpose of this study was to evaluate the practical application of these ELISAs for clinical use with a large number of serum samples. We used 81 PV sera, 48 PF sera, 114 bullous pemphigoid (BP) sera, 124 collagen disease sera, nine sera of other non-pemphigus bullous diseases and 179 normal control sera. A cut-off value was determined by receiver-operating-characteristic plots. Forty-seven of 48 PF sera (97.9%) were positive in the Dsg1 ELISA and 79 of 81 PV sera (97.5%) were positive in the Dsg3 ELISA, while only two (1. 1%) and four (2.2%) of 179 normal sera were positive in Dsg1 and Dsg3 ELISAs, respectively. However, some disease control sera of BP and collagen diseases exceeded the cut-off value. Introduction of a grey zone helped to decrease the number of these false-positive sera. Furthermore, in three patients studied, the respective Dsg1 and Dsg3 ELISA scores showed parallel fluctuation with the disease activity along the time course. We conclude that Dsg1 and Dsg3 ELISAs provide a simple, sensitive and highly specific assay for the diagnosis of patients with PV and PF and that these ELISAs may be a valuable tool to monitor the disease activity. We also propose diagnostic criteria for pemphigus based on ELISA reactivity: if a serum is positive against Dsg3 it indicates a diagnosis of PV, regardless of reactivity against Dsg1; if a serum is negative for Dsg3 and positive for Dsg1, it indicates a diagnosis of PF.     

Characterization of bullous pemphigoid antigen synthesized by cultured human squamous cell carcinoma cells

This report concerns the characterization of bullous pemphigoid antigen (BPA) in cultured cells derived from a human squamous cell carcinoma (SCC cells) as identified by sera of 9 patients with bullous pemphigoid (BP). Immunoglobulin G from 5 of 9 BP sera bound the cell surfaces of SCC cells with a punctate staining pattern by immunofluorescence. The other four BP sera and all 12 controls sera showed no specific staining. To characterize the antigen for pemphigoid antibody, we immunoprecipitated NP-40 extracts of cells labeled with [14C] amino acids using nine BP sera and 12 controls sera. These immunoprecipitates were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis and by fluorography. The five BP sera that gave positive immunofluorescence results also precipitated a protein with molecular weight (mol wt) of 110 kD, whereas the other four BP sera negative by immunofluorescence and all 12 controls sera did not precipitate this protein. These results indicate that the sera of patients with BP contain antibodies against the protein with mol wt 110 kD in the SCC cells used in this study. With use of four BP sera, two of which were positive to this mol wt 110 kD BPA and two of which were negative, immunoprecipitation was carried out in Pam cells. One 110 kD-positive serum and two 110 kD-negative sera, precipitated a BPA of mol wt 220 kD from Pam cells labeled with [35S] methionine. These results suggest that BP sera may recognize more than one antigen, in addition to possible BPA heterogeneity in different individuals.