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In psoriatic skin, laminin integrity is altered, which could lead to insufficient laminin integrin interactions, leaving the α6-integrin exposed and possibly accessible for autoantibody production. Therefore we investigated the presence of anti-α6-integrin autoantibodies in the serum of patients with psoriasis vulgaris (Ps), psoriatic arthritis (PsA) and rheumatoid arthritis (RA) in comparison with healthy donors. The level of circulating anti-α6-integrin antibodies was determined by enzyme-linked immunoassay using α6-integrin fragments. Antibodies against at least one recombinant fragment were found in approximately 30% of Ps and PsA patients. In contrast, in RA patients, the frequency of antibodies was similar to healthy controls. Our study shows the presence of anti-α6-integrin antibodies in Ps and PsA but not in RA, which could indicate ongoing abnormal processes in the skin. Anti-α6-integrin autoantibodies may contribute to the formation of micro-wounds in the skin and to the characteristic wound-healing phenotype in psoriasis., (© 2016 Japanese Dermatological Association.)

Objectives: Antimuscarinic acetylcholine receptor-3 (m3AChR) autoantibodies have been described in primary Sjögren's syndrome (pSS). The aim of this study was to compare various methods for their detection and to assess the contributions of anti-m3AChR and other immunological and psychosocial factors to the pathomechanism of secondary SS (sSS)., Methods: Sixty-five rheumatoid arthritis (RA) patients, 103 systemic lupus erythematosus (SLE) patients, 76 pSS patients and 50 controls were compared. Three immunodominant epitopes of m3AChR were synthesized and used in ELISA. Two extracellular epitopes were also prepared in fusion with glutathione-S-transferase and one in conjugation with bovine serum albumin. Mental health status was assessed with the 36-item Short-Form Health Survey and Functional Assessment of Chronic Illness Therapy fatigue scale. Correlations were evaluated between glandular function and anti-m3AChR positivities and specificities, features of SLE and RA, and mental health parameters., Results: Fourteen RA and 27 SLE patients had sSS. The autoantibody levels to all epitopes of m3AChR were significantly higher in pSS and SLE patients than in the controls. The fusion protein forms discriminated RA from pSS and SLE; furthermore, the YNIP fusion protein also distinguished pSS from SLE. The prevalence and the mean levels of all autoantibodies did not differ statistically between sicca and non-sicca SLE or RA patients. Glandular dysfunction correlated with higher age in SLE and RA and an impaired health-related quality of life in SLE., Conclusions: The second and third extracellular loops of m3AChR are antigenic in pSS. Immunoassays with antigens as fusion peptides demonstrate the best performance. Sicca SLE patients have worse mental health status. Anti-m3AChR antibodies represent a peculiar example of neuroimmune interactions., (Copyright © 2012 S. Karger AG, Basel.)

Antibodies against citrullinated proteins/peptides (ACPAs), and especially antibodies targeting mutated citrullinated vimentin (anti-MCVs), are novel biomarkers of rheumatoid arthritis (RA). Whereas ACPAs are specific and sensitive markers for RA, there have hardly been any reports relating to ACPAs in psoriatic arthritis (PsA) or in psoriasis without joint symptoms (PsO). The aim of the present study was to investigate the prevalence of anti-MCVs in PsA and PsO. Serum anti-MCV titers were measured in 46 PsA and 42 PsO patients and in 40 healthy controls by means of a commercial enzyme-linked immunosorbent assay. The potential correlations of the serum autoantibody levels with several clinical and laboratory parameters were examined. The anti-MCV levels in the PsA patients were significantly higher than those in the PsO group. Among the clinical variables, the presence of tender knee joints and nail psoriasis was significantly associated with anti-MCV positivity in the PsA patients. Higher anti-MCV titers in the PsO patients were associated with a more severe disease course and with the early onset of psoriatic skin symptoms. Our results suggest that anti-MCVs can be used as novel markers in the diagnosis of PsA and in a subset of PsO patients.

The authors present their experience related to the diagnosis, treatment, and followup of 431 patients with bullous pemphigoid, 14 patients with juvenile bullous pemphigoid, and 273 patients with pemphigus. The detection of autoantibodies plays an outstanding role in the diagnosis and differential diagnosis. Paraneoplastic pemphigoid is suggested to be a distinct entity from the group of bullous pemphigoid in view of the linear C3 deposits along the basement membrane of the perilesional skin and the "ladder" configuration of autoantibodies demonstrated by western blot analysis. It is proposed that IgA pemphigoid should be differentiated from the linear IgA dermatoses. Immunosuppressive therapy is recommended in which the maintenance dose of corticosteroid is administered every second day, thereby reducing the side effects of the corticosteroids. Following the detection of IgA antibodies (IgA pemphigoid, linear IgA bullous dermatosis, and IgA pemphigus), diamino diphenyl sulfone (dapsone) therapy is preferred alone or in combination. The clinical relevance of autoantibodies in patients with autoimmune bullous dermatosis is stressed.

Bullous pemphigoid (BP) is characterized immunologically by tissue-bound and circulating autoantibodies targeting the hemidesmosomal proteins BP230 and BP180. Recent evidence suggests a pathophysiological role for autoantibodies against alpha6 integrin in the subepidermal blister formation of oral pemphigoid. The objective of our study was to investigate the presence of anti-alpha6 integrin antibodies in patients with classical BP. The autoantibody profiles of 30 patients with BP, 10 patients with pemphigus vulgaris, and 20 healthy persons were identified. With the use of PeptideStructure and PlotStructure software, four different antigenic epitopes for alpha6 integrin were predicted, and their fusion recombinant constructs were prepared in an E. coli expression system. Sera were tested for alpha6 integrin autoantibodies by an ELISA technique. Altogether, 52% of the patients with BP displayed circulating antibodies against at least one recombinant protein. Our findings provide the first evidence for the presence of anti-alpha6 integrin antibodies in patients with classical BP.

Background: Some cases of Tourette's syndrome (TS) are hypothesized to be caused by autoantibodies that develop in response to a preceding group A beta hemolytic streptococcal infection., Methods: To test this hypothesis, we looked for the presence ot total and IgG antibodies against neural, nuclear, cytoskeletal and streptococcal epitopes using indirect immunofluorescent assays and Western blot techniques in three patient groups: TS (n = 81), SC (n = 27), and a group of autoimmune disorders (n = 52) and in normal controls (n = 67). Subjects were ranked after titrations of autoantibodies from 0 to 227 according to their level of immunoreactivity., Results: TS patients had a significantly higher mean rank for total antineural and antinuclear antibodies, as well as antistreptolysin O titers. However, among children and adolescents, only the total antinuclear antibodies were increased in TS patients compared to age matched controls. Compared to SC patients, TS patients had a significantly lower mean rank for total and IgG class antineural antibodies, significantly lower IgG class anticytoskeletal antibodies, and a significantly higher rank for total antinuclear antibodies. Compared to a mixed group of autoimmune disorders, the TS patients had a significantly lower mean rank for total and IgG class antineural antibodies, total and IgG class antinuclear antibodies, IgG class anticytoskeletal antibodies, and a significantly higher rank for antistreptococcal antibodies., Conclusions: TS patients had significantly higher levels of total antineural and antinuclear antibodies than did controls. Their relation to IgG class antineural and antinuclear antibodies, markers for prior streptococcal infection, and other clinical characteristics, especially chronological age, was equivocal.

Specific antibodies directed against special hemidesmosomal proteins are involved in the pathogenesis of bullous pemphigoid (BP), and detection of these antibodies is crucial for a correct diagnosis. As the BP autoantigen primary structures are known, the question was addressed as to whether it is possible to demonstrate circulating antibodies against BP autoantigens (BPAG1 and BPAG2) by means of an ELISA system, using antigenic epitopes. With the help of the programs Peptidestructure and Plotstructure, antigenic epitopes of BP antigens were predicted, chemically synthesized and screened using serum from 43 proven BP patients. The coding sequences of the best antigenic epitopes were then chemically synthesized and inserted as monomer and homo- or hetero-oligomer forms into fusion-expression plasmids (PGEX-4T, Pharmacia) in-frame to the C-terminus of glutathione-S-transferase. Fusion products were expressed and purified from Escherichia coli cells by affinity chromatography. The recombinant proteins were used for the detection of antibodies in the serum of 43 BP patients and of 60 controls (including 30 healthy persons, 22 patients with pemphigus vulgaris and 8 patients with other bullous dermatoses). Use of the homo- and hetero-oligomers of the recombinant fusion peptides increased the sensitivity of the disease-specific antibody detection. When a mixture of the best recombinant fusion proteins was used, the sensitivity of the ELISA assays in the case of the BP patients' serum was 0.90. This system could form the basis of a rapid and simple system for the diagnosis of BP.

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.

In an earlier study, the circulating autoantibodies in patients with bullous pemphigoid (BP) were demonstrated in higher frequencies by means of an immunoblot technique then via indirect immunofluorescence. In the present work with the help of Peptide Structure software, two matched antigenic epitopes were chosen and synthesized. The sera of 34 patients with BP were investigated in parallel by an immunoblot technique using a human epidermal extract, and by an ELISA technique with synthetic peptides. The sera of 16 healthy persons and 10 patients with other bullous diseases served as controls. Among the 34 patients with BP, 23 sera proved positive for at least one synthetic peptide. Positive reactions with the major BP antigen (230 kD) were found in 22 patients by immunoblot technique and in 16 patients by the ELISA technique with the synthetic peptide, whereas with the minor BP antigen (180 kD), positive reactions were found in 9 patients by the immunoblot technique and 18 patients by the ELISA technique using the synthetic antigenic epitope of the minor BP antigen. All control sera were negative for both antigens in ELISA investigations. In 3 patients with pemphigus vulgaris, characteristic bands against pemphigus vulgaris antigen were identified by means of the immunoblot technique, but all other cases were negative. It is suggested that the development of this technique may lead to an opportunity for the rapid and simple diagnosis of BP.

Antibodies against ENA (Extractable Nuclear Antigens), SSA/Ro and SSB/La were investigated in parallel in the serum and the immune complex precipitates of 41 patients with autoimmune disease (10 systemic lupus erythematosus, 23 discoid lupus erythematosus, 3 subacute cutaneous lupus erythematosus, and 5 progressive systemic sclerosis). It was demonstrated that in some cases the autoantibody spectrum of the serum did not coincide with that of the immune complex precipitate. In the majority of patients the protein content of isolated immune complexes was increased and the increase was attributed to IgG solely. In some patients antibodies appeared not only in the serum but also in immune complex, even in 4 patients (2 systemic lupus erythematosus, 1 subacute cutaneous lupus erythematosus, and 1 progressive systemic sclerosis) antibodies were detected only in the immune complex precipitate.