Immunoserological area--with special reference to the current topics on antinuclear antibodies

In 1948, Hargraves described the phenomenon of the LE cells and equated it with systemic lupus erythematosus (SLE). Kunkel and his colleagues elucidated the immunochemical basis of this phenomenon, showing that it was related to the circulating autoantibodies to deoxyribonucleoprotein (DNP). Their pioneering studies led to the continuing discoveries of antinuclear antibodies (ANA) and today's considerable knowledge concerning the molecular identity of antigens and further consolidation of ANA. In addition to the role of diagnostic markers, spontaneously occurring autoantibodies, including anti-PCNA (proliferating cell nuclear antigen) antibody and anticentromere antibody (ACA), turned out to be useful as powerful probes for cell biology. In this study, the sera of patients with primary biliary cirrhosis (PBC) along with collagen diseases were examined for the presence of antinuclear antibodies. In using HEp-2 cells and chromosomes derived from K 562 as the substrates for the immunofluorescence method, the frequency of ANA and ACA in PBC sera were 84% and 44% respectively. Anti-DNA, antiSS-A and antiSS-B antibodies were found in one, 4 and one sera respectively. On the other hand, antibodies to nRNP, Sm and Scl-70 were not found in PBC sera. In some PBC patients with ACA, various complications related to collagen diseases were found to coexist. Our results indicated that there might be common serological abnormalities among patients with PBC, CREST syndrome and Sj?gren's syndrome.     

Induction of anticentromere antibody in patients receiving treatment with D-penicillamine

Summary Anticentromere antibody (ACA) was previously described as a specific marker for CREST, progressive systemic sclerosis (PSS), scleroderma (SCL), Raynaud's phenomenon (RP) and primary biliary cirrhosis (PBC). In this present investigation ACA was observed appearing and disappearing due to D-penicillamine (DPA) treatment in 7 patients without any features of CREST, PSS, SCL, RP or PBC. HLA-DR3 was found in 5/7 of these patients. DPA induced ACA should be added to adverse immunologic drug reactions.Abbreviations ab antibody - ACA Anticentromere ab - CREST Calcinosis-Raynaud's phenomenon-esophageal dysmotility-sclerodactyly-telangiectasias-syndrome - DPA D-penicillamine - HLA Human leukocyte antigen - PBC Primary biliary cirrhosis - PSS Progressive systemic sclerosis - RA Rheumatoid arthritis - RP Raynaud's phenomenon - SCL Scleroderma - SNP Seronegative Polyarthritis     

Immunological characterization of heterochromatin protein p25β autoantibodies and relationship with centromere autoantibodies and pulmonary fibrosis in systemic scleroderma

 Anticentromere antibodies (ACA) are immunological markers for the subset of systemic scleroderma with the symptoms calcinosis cutis, Raynaud’s phenomenon, esophageal dysfunction, sclerodactyly, and telangiectasia (CREST). In western blotting, some ACA-positive sera also recognize a doublet of 23 kDa (p23) and 25 kDa (p25) in addition to centromere protein antigens A (17 kDa), B (80 kDa), and C (140 kDa). Two forms of p25 have been shown to be human homologues of Drosophila heterochromatin-associated protein HP1. One form of p25 (p25β) which was recently cloned in this laboratory was used to evaluate anti-p25β antibody response in scleroderma sera. Of 318 scleroderma sera 42 had ACA (13.2%), and 16 of the 42 sera (38%) had anti-p25β antibodies. On the other hand, 5 of 276 ACA-negative sera (1.8%) showed anti-p25β antibody response, demonstrating that anti-p25β antibody is significantly associated with the ACA response (P<10^–8). Clinically the anti-p25β response was significantly associated with the CREST syndrome. Fourteen (36.8%) of 38 CREST patients compared to seven (2.5%) of 280 patients with other forms of scleroderma were anti-p25β antibody positive (P<10^–8). The 14 CREST patients with anti-p25β antibodies had significantly more interstitial lung disease than those without anti-p25β antibodies (P<0.003). There was also a tendency to increased liver involvement. Two dominant autoepitopes in p25β were determined by western blotting using p25β recombinant fragments. In immunofluorescence C-terminal specific antibodies showed staining of heterochromatin, but N-terminal specific antibodies showed no staining. Interestingly, the majority of sera reacted preferentially with one or the other of the two dominant autoepitopes. Received: 6 March 1997 / Accepted: 21 July 1997     

Anti-M4 antibodies measured by a sulphite oxidase ELISA in patients with both anti-centromere and anti-M2 antibodies.

In this study the clinical features of patients with a serological overlap between scleroderma and primary biliary cirrhosis (PBC) were analysed. The entity was defined by the presence of both anti-centromere antibody (ACA) and anti-mitochondrial antibodies to the M2 antigen, pyruvate dehydrogenase. In addition the sera were assayed for anti-mitochondrial antibodies to the M4 antigen measured by an ELISA to sulphite oxidase (SO). First, anti-M2 was detected, not only in 58 out of 60 patients with PBC but also in eight out of 61 patients with ACA. These sera, together with sera from 53 normals and 99 from patients with various connective tissue diseases were then evaluated for anti-SO, which has been proposed by Klein and Berg to be a marker of progressive liver disease. Again, a high proportion (62%) of sera from patients with PBC were positive for anti-SO, and three of the eight patients who had ACA and anti-M2 also reacted with SO. We subsequently identified and included for study a further 10 patients positive for ACA and anti-M2, making a total of 18 patients with this profile. Features of limited cutaneous scleroderma were present in 94% and evidence of liver disease in 56%. Eight out of the 18 patients had anti-SO, and of these four had PBC, two had abnormal biochemical liver function tests but two had no evidence of liver disease. These data confirm that detection of anti-SO is limited to an anti-M2 subpopulation, and may be a marker for liver involvement with prognostic significance in scleroderma patients with ACA.     

Primary biliary cirrhosis and Sjögren's syndrome: autoimmune epithelitis

Primary biliary cirrhosis (PBC) has been often coined a model autoimmune disease based on the homogeneity amongst patients, the frequency and similarity of antimitochondrial antibodies, including the highly directed immune response to pyruvate dehydrogenase (PDC-E2). A significant number of patients with PBC suffer from sicca and amongst these, there are patients who also have classic Sj?gren's syndrome. Indeed, both PBC and Sj?gren's syndrome are characterized by inflammation of target epithelial elements. Both diseases can be considered on the basis of a number of other related clinical aspects, including proposed unique apoptotic features of the target tissue, the role of secretory IgA, and the frequency with which both diseases overlap with each other. Indeed, PBC may be considered a Sj?gren's syndrome of the liver, whereas Sj?gren's syndrome can be equally discussed as PBC of the salivary glands. Dissection of the genetic predispositions for both diseases and especially the molecular basis of effector mechanisms, will become critical elements in developing new therapies.     

Identification of antigenic regions of the human Ro 60 kDa protein using recombinant antigen and synthetic peptides.

Autoantibodies reacting with the human Ro 60 kDa protein are present in anti-Ro/SS-A positive sera from patients with several different connective tissue diseases including Sj?gren's syndrome and systemic lupus erythematosus. To investigate the humoral immune response to this protein, the pattern of antibody recognition of recombinant Ro 60 kDa proteins encoded by both full-length and deletion clones was analysed by immunoblotting. An antigenic region recognized by nearly all anti-Ro 60 kDa positive sera was found to reside in the middle part of the protein. In addition, some sera reacted with two other antigenic regions located in the amino-terminal and carboxyl-terminal part of the protein. For further mapping, overlapping peptides covering the most frequently recognized region of the protein were synthesized by solid-phase methods and used as antigens in ELISA. Three major patterns of reactivity to Ro 60 kDa peptides were found. These results not only indicate the presence of an immunodominant region but also heterogeneity in the autoimmune human response to the Ro 60 kDa antigen.     

Detection of anti-early endosome antigen 1 antibody in sera showing cytoplasmic vesicular staining,taken from patients with connective tissue diseases

An early endosome antigen previously reported by F.T. Mu could be stained on cytoplasmic vesicles of HEp-2 cells. Here, we have investigated autoantibodies against cytoplasmic vesicular antigens, especially against early endosome antigen 1. Twelve sera were selected on the basis of cytoplasmic vesicular staining patterns of HEp-2 cells. Protein-immunoprecipitation using 35S-methionine labeled HeLa lysates, and RNA immunoprecipitation using 32P-labeled HeLa lysates were conducted to characterize the cognate antigens. Nine of 12 sera reacted with proteins in the range of 162-180 kDa, three of which were found to react specifically with the 162 kDa 35S methionine labeled recombinant early endosome antigen 1. These proteins were not associated with common RNA. Although complete clinical information was not available, some of the patients had rheumatoid arthritis(RA). In addition, the RNA-IPP results suggest that other patients included one each with SLE, SSc, polymyositis, and Sj?gren's syndrome. Anti-early endosome antigen 1 antibody was found in 25%(3 of 12) of sera known to stain cytoplasmic vesicles. The reactive sera came mostly from patients with RA. The sera was from one case each of clinical-confirmed RA, SLE and Sj?gren's syndrome.     

Autoimmune diseases other than lupus share common anti-DNA idiotypes

We examined the sera of 170 patients with various autoimmune diseases other than systemic lupus erythematosus (SLE) for the presence of an anti-DNA antibody idiotype termed 16/6 and known to occur with high frequency in sera of patients with SLE. The idiotype was found in 6/15 sera from patients with polymyositis (49%), 3/18 with multiple sclerosis (17%), 3/18 with primary Sj?gren's syndrome (18%), 9/40 with autoimmune thyroid diseases (23%), 2/35 with myasthenia gravis (6%), and 3/42 patients with rheumatoid arthritis (7%). The idiotype was not detected among 12 patients with scleroderma or 77 normal controls. The presence of the 16/6 idiotype was associated with the presence of another anti-DNA idiotype termed 134-Id. Serum samples were also tested for activity against DNA, various synthetic polynucleotides, and cardiolipin. The serum activity against these antigens was found to be polyspecific, though overlap in reaction against the various polynucleotides was not absolute. The 16/6 idiotype is thought to be coded by a germline gene. The presence of this idiotype in various autoimmune diseases points to a pathophysiologic link between the diseases.     

Antimitochondrial (pyruvate dehydrogenase) autoantibodies in autoimmune rheumatic diseases

Anti-pyruvate dehydrogenase (PDH) antibodies were determined in 1451 sera of patients with primary biliary cirrhosis (PBC) and several autoimmune rheumatic conditions by ELISA and immunoblotting. They were detected in sera of 93% of the patients with PBC (179 of 192 patients) in 60 of 277 (22%) patients with Sjogren's syndrome (SjS), 34 of 437 (8%) patients with scleroderma, 33 of 191 patients with SLE (17%), and 5 of 55 (10%) patients with rheumatoid arthritis (RA) but in none of the patients with polymyositis or the antiphospholipid syndrome. The ELISA studies were confirmed by immunoblots showing binding of autoimmune rheumatic sera to the same epitope (74 kd) of mitochondria that the PBC sera reacted with. The identical binding characteristics were also confirmed by protein competition assays with purified PDH. In 4 of 53 patients with SjS who were positive for anti-PDH, high titers as in PBC were detected. The anti-PDH antibodies in Sjogren's patients were associated with deranged liver function tests and extraglandular features but did not correlate with any other non-organ-specific antibody. Follow-up studies confirmed the association of the emergence of anti-PDH antibodies with defects in liver function tests. The antibodies were more prevalent in SLE and RA when they were associated with Sjogren's syndrome (30 and 18.8%, respectively). Among patients with different forms of scleroderma, anti-PDH antibodies were noted in subjects with systemic sclerosis, morphea, and Raynaud's phenomenon. The incidence was much more significant among patients with calcinosis, Raynaud's, esophageal dysmotility, sclerosis, and telangiectasia (CREST) (8/34), in whom antibodies were detected in 5 who had already developed PBC. The relationship among anti-PDH antibodies, PBC, and development of other autoimmune rheumatic conditions is discussed. It is proposed that the early detection of anti-PDH antibodies in patients with rheumatic conditions may predict the future development of PBC. This observation may have therapeutic implications.     

Detection of anti-SS-A/Ro and anti-SS-B/La antibodies of IgA and IgG isotypes in saliva and sera of patients with Sj?gren's syndrome.

To assess the frequency and the possibility of local production of autoantibodies against SS-A/Ro and SS-B/La in patients with primary Sj?gren's syndrome (SS), serum and saliva samples were obtained from 42 patients with SS, 10 with rheumatoid arthritis without sicca syndrome, and 12 healthy volunteers. Autoantibodies were detected using enzyme-linked immunosorbent assay and immunoblotting. The frequencies of IgA anti-SS-A antibody, IgA anti-SS-B antibody, IgG anti-SS-A antibody and IgG anti-SS-B antibody in serum from SS patients were 45%, 50%, 43% and 21%, respectively. The frequencies of IgA anti-SS-A antibody, IgA anti-SS-B antibody, IgG anti-SS-A antibody and IgG anti-SS-B antibody in saliva from SS patients were 31%, 33%, 40%, and 19%, respectively. We also found secretory IgA anti-SS-A and anti-SS-B antibodies accompanying secretory components in saliva and sera in representative SS patients. Significant correlations were found between serum and salivary levels of IgA anti-SS-A antibodies, and between serum and salivary levels of IgA anti-SS-B antibodies in SS patients. Significant correlations were also found between serum and salivary levels of IgG anti-SS-A antibodies, and between serum and salivary levels of IgG anti-SS-B antibodies in SS patients. Immunoblot analysis confirmed the presence of IgA-class autoantibodies against SS-A and SS-B in saliva and serum from representative patients. The presence of IgA- and IgG-class autoantibodies against SS-A and SS-B and those accompanying secretory components in saliva from SS patients suggests the local production of these antibodies and the relationship between local and systemic antibody responses.     

The development of a quantitative assay for the detection of anti-Ro/SS-A and anti-LA/SS-B autoantibodies using purified recombinant proteins.

A characteristic of patients with autoimmune diseases such as Sj?gren's syndrome and systemic lupus erythematosus is the presence of anti-Ro/SS-A and anti-La/SS-B autoantibodies in their circulation. In order to investigate specific autoantibody levels in the sera of these patients quantitative assays for the detection of both anti-Ro/SS-A and anti-La/SS-B reactivity were developed. Ro/SS-A (60 kDa) and La-SS-B (50 kDa) cDNAs were cloned and expressed in E. coli as non-fusion proteins. These were purified to homogeneity using two different purification protocols. With these recombinant antigens, specific enzyme-linked immunosorbent assays (ELISAs) were developed. 40 sera positive for anti-Ro/SS-A autoantibodies in counterimmunoelectrophoresis (CIE) were tested in both the Ro/SS-A and La/SS-B ELISA. Activity values reproducibly ranged from 1536 to 120,000 U in the Ro/SS-A ELISA and from 763 to 2,500,000 U in the La/SS-B ELISA. The suitability of these ELISAs as screening assays was further investigated by testing 200 sera sent to our laboratory for routine detection of autoantibodies to extractable nuclear antigen (ENA: anti-Sm, anti-RNP, anti-Ro/SS-A and anti-La/SS-B). Both ELISAs showed a high sensitivity and specificity (Ro/SS-A ELISA 85% and 94%, La/SS-B ELISA 100% and 98% respectively), when compared to the standard assays, the RNA-precipitation assay and the HeLa immunoblotting test. From these data we conclude that a quantitative analysis of both anti-Ro/SS-A and anti-La/SS-B autoantibodies is now possible using purified recombinant non-fusion proteins. For screening purposes the La/SS-B ELISA showed a great improvement in sensitivity for the detection of anti-La/SS-B activity in comparison to the La/SS-B CIE, while the Ro/SS-A ELISA almost equalled the performance of the Ro/SS-A CIE.     

Proteins responsible for anticentromere activity found in the sera of patients with CREST-associated Raynaud''s phenomenon.

Anticentromere antibodies (ACA) present in a high percentage of patients with complete or incomplete CREST scleroderma, and which are presently used in the diagnosis of this disease, also appear in some primary Raynaud's phenomenon patients. Three principal centromeric antigens, CENP-A, CENP-B and CENP-C, have been described as reacting with the sera of these individuals. We attempt to determine whether or not a correlation between the presence of ACA and serum reactivity against one or more of these peptides could be established, and have observed that CENP-A, but not CENP-B or CENP-C, is specifically recognized by all patients sera tested. The fact that this reactivity is clearly detectable at very high serum dilutions, thus eliminating other non-specific interference, suggests that anti-CENP-A activity might be useful in the diagnosis of patients with CREST-associated Raynaud's phenomenon.     

Demonstration of high prevalence of SS-A antibodies in a general population: association with HLA-DR and enterovirus antibodies

Autoantibodies are helpful markers for diagnosing autoimmune diseases and there is a link between HLA-DR3 and the prevalence of SS-A antibodies in clinical groups. We aimed to study this association at the level of general adult population and to verify whether these antibodies are more common in persons with antibodies against enteroviruses as possible associates of Sj?gren syndrome. The studied material included sera from 200 persons, randomly selected from a general population sample. The IgG type of SS-A/SS-B autoantibodies were measured by nuclear immunoblot, developed by us, and the results were compared to other results obtained by anti-SS-A immunoblot and ELISA. Enterovirus antibodies were detected by ELISA using common enterovirus antigenic peptide KEVPALTAVETGAT. Altogether 33 out of 200 sera showed SS-A and/or SS-B bands in immunoblot, including all seven ANA Profile 3 (Euroimmune) positive sera. One of the persons positive in these two tests showed also positive reaction on anti-SS-A ELISA (Euroimmune). None of the antibody-positive persons had Sj?gren's syndrome or other rheumatic disease. Among 82 HLA typed persons, selected at random, the HLA-DRB1*03 and HLA-DRB1*11 allele carriers included significantly more persons with SS-A antibodies than the non-carries (p = 0.008). Antibodies against enterovirus peptide were present more frequently in persons with SS-A autoantibodies than in age- and sex-matched controls (p = 0.009). Summing up, our study showed that the prevalence of SS-A/SS-B antibodies in a general random population might be higher than thought previously being detected in up to 16.5% of persons including a significant number of those with HLA-DR3 or/and DR11 alleles and with antibodies against enteroviruses. Whether all these persons have the risk of developing rheumatic diseases should be evaluated by follow up studies.     

Detection of autoantibody to mitotic spindle associated antigen (MSA) in sera from patients with positive mycoplasma pneumoniae particle agglutination (PA) test]

Autoantibody to mitotic spindle associated antigen (MSA) was examined in sera from patients with positive mycoplasma pneumoniae particle agglutination (PA) test along with various autoimmune diseases and healthy subjects by means of indirect immunofluorescence (IF) using HEp-2 cells as substrates. Anti-MSA antibody was identified in 9 patients sera including 7 out of 180 sera with positive mycoplasma pneumoniae PA test, one with systemic lupus erythematosus (SLE) and one with scleroderma (PSS) respectively. Five of 9 sera with positive anti-MSA antibody contained anti-nuclear antibody (ANA) including 4 with speckled staining ANA and one with homogeneous + nucleolar staining ANA. Two collagen diseases sera positive for anti-MSA antibody showed negative mycoplasma pneumoniae PA test. In addition, there was no correlation between the presence of anti-MSA antibody and the titers of mycoplasma pneumoniae PA test. Our results indicated that anti-MSA antibody was not limited to such connective tissue diseases as previously described by other workers. It would be speculated that mycoplasma pneumoniae infection might induce anti-MSA antibody production.     

A major autoepitope is present on the amino terminus of a human SS-A/Ro polypeptide

A human SS-A/Ro antigen is present on the polypeptide component of a particle composed of hyRNA and a 60 kD protein. We have now purified the Wil-2 cell 60 kilo dalton (kD) SS-A/Ro protein and determined its amino-terminal amino acid sequence. A synthetic peptide corresponding to residues 7 to 24 of this sequence (RoSP7-24) exhibited enzyme-linked immunosorbent assay (ELISA) binding activity with immunodiffusion-defined, monospecific anti-SS-A/Ro sera. In addition, ELISA binding of monospecific anti-SS-A/Ro sera to native SS-A/Ro antigen was partially inhibited (35%) by KLH-RoSP7-24. Sera from patients known to frequently produce precipitating anti-SS-A/Ro antibody (subacute cutaneous lupus erythematosus [SCLE], 56 patients; Sj?gren's syndrome [SS], 41 patients; mothers of infants with neonatal LE [NLE], 10 individuals; infants with congenital heart block [CHB], 5 patients) were tested for reactivity to RoSP7-24 in ELISA. Overall, 38% of SCLE sera, 36% of SS sera, 50% of maternal NLE sera and 20% of CHB infant sera had anti-RoSP7-24 binding levels greater than 2 standard deviations above the mean of that of normal individuals. Of the sera which had anti-SS-A/Ro detected by double immunodiffusion and/or counterimmunoelectrophoresis, 68% of SCLE patients, 71% of SS patients, 55% of NLE mothers and 20% of CHB infants had significantly elevated RoSP7-24 ELISA binding levels. These findings strongly suggest that a major autoepitope of native human SS-A/Ro resides on the amino terminal portion of the Wil-2 SS-A/Ro 60 kD polypeptide.(ABSTRACT TRUNCATED AT 250 WORDS)     

Antibodies to La, Jo-1, nRNP and Sm detected by multi-track immunoblotting using a novel filter holder: a comparative study with counterimmunoelectrophoresis and immunodiffusion using sera from patients with systemic lupus erythematosus and Sj?gren's syndrome

The use of Western blotting or immunoblotting to detect autoantibodies in the serum of patients with autoimmune connective tissue diseases was investigated. An apparatus suitable for simultaneously screening 16 sera on immunoblots was used to show that a complex pattern of antibody binding polypeptides was present in whole HeLa cells. A simpler and readily interpreted pattern of binding was achieved using affinity-purified rabbit thymus antigens. Seventy-seven patients with systemic lupus erythematosus, 44 with primary Sj?gren's syndrome and 50 normals were screened for anti-Sm, anti-La, anti-nRNP and anti-Jo-1 by immunoblotting and the results compared with those obtained by counterimmunoelectrophoresis and immunodiffusion. It was shown that both IgG and IgM antibodies must be analysed on immunoblots to detect the maximum number of positive sera, and that the immunoblot detects many anti-La sera which do not form precipitins.     

An antibody reacting with splenic red pulp macrophages in the sera of patients with rheumatic diseases

An antibody was detected in the sera of patients with certain rheumatic diseases that reacted with the cytoplasm of the splenic red pulp (SRP) cells of adult mice. This antibody was detected in the sera of all patients with mixed connective tissue disease (MCTD), 53% of patients with systemic lupus erythematosus (SLE), 42% with Sj?gren's syndrome (SS), and 10% with rheumatoid arthritis (RA). However, this antibody was found neither in the sera from patients with other types of rheumatic diseases nor in healthy volunteers. The screening of this antibody may be useful in diagnoses of MCTD, SLE, and SS. In the present study, we also performed the characterization of the cells reacting with this antibody. The cells proved to be acid phosphatase positive phagocytes in the SRP, that is, red pulp macrophages. Moreover, a histochemical analysis of the reacting antigen in these cells has demonstrated that its antigenic activity is NaIO4 and RNase sensitive, suggesting that the antigen may be associated with RNA.     

Clinical evaluation of serum cytokine from patients with collagen diseases]

PURPOSE: Systemic autoimmune diseases such as systemic lupus erythematosus (SLE) and Sj?gren's syndrome (SS) are characterized by an imbalance of cytokine production. To clarify the relationship between the profile of cytokines and the pathophysiology of systemic autoimmune diseases, we estimated the cytokine levels in sera from patients with several systemic autoimmune diseases. METHOD: Serum cytokine levels in patients with unclassified connective tissue diseases were measured using ultrasensitive specific enzyme-linked immunosorbent assay (ELISA). RESULT: These patients were diagnosed using the established category by further examinations within a 2-year period. Sera from patients with SLE contained higher titers of IL-10, and equal levels of IFN gamma and TNF alpha compared with those of normal controls. Patients with progressive systemic sclerosis (PSS) showed lower titers of IL-10 and higher titers of IFN gamma and TNF alpha in their sera than those of healthy controls. Seronegative rheumatoid arthritis (snRA) patients had a higher amount of IL-10 and TNF alpha, equivalent level of IFN gamma in their sera compared to those of controls. Moreover, patients with Sj?gren's syndrome (SS) showed higher titers of IL-10 and TNF alpha, and an equivalent level of IFN gamma in their sera compared to healthy volunteers. CONCLUSION: Based on these findings, for the differential diagnosis of patients with systemic autoimmune diseases such as SLE, PSS, snRA and SS, it may be useful to measure the levels of cytokines such as IL-10, IFN gamma, and TNF alpha in their sera.     

The comparison in double immunodiffusion and western blotting methods of anti-SS-A/B antibodies in patients with Sj?gren's syndrome]

OBJECTIVE: To investigate the autoimmune responses against SS-A/B antigens by double immunodiffusion (DID) and western blotting (WB) in primary and secondary Sj?gren's syndrome (SS). PATIENTS: Forty-nine patients with primary SS (PSS), 28 patients with secondary SS (SSS) and control group that couldn't be diagnosed as SS were included in this study. RESULTS: In DID analysis, Anti-SS-A antibody was detected in 69% of PSS and 86% of SSS, and anti-SS-B antibody was found in 22% of PSS and 39% of SSS. No significant difference could be demonstrated between PSS and SSS concerning anti-SS-A/B antibodies. Conversely, WB studies disclosed evidences that 18% of PSS and no SSS reacted only with the 52 kD protein, and there was significantly increased in PSS. Sera reacting with the 60 kD antigen were found in 37% of PSS, 71% of SSS, and 75% of SSS with SLE, 63% of SSS with RA. The ratio of SSS, and SSS with SLE were particularly significantly higher than PSS. CONCLUSION: Our results revealed data that there are the difference of reactivity against SS-A/B antigens in WB between PSS and SSS.     

Clinical and immunological features of Sj?gren's syndrome in patients with primary biliary cirrhosis with emphasis on focal sialadenitis

Serological and pathological findings in 21 patients with primary Sj?gren's syndrome (primary SS) were compared with those in 32 patients with primary biliary cirrhosis (PBC). In ELISA, anti-SS-B/La antibodies were detected in sera from 14 (67%) of the patients with primary SS, but only from 12 (38%) of those with PBC. With the Ouchterlony test, anti-SS-A/Ro antibodies were found in sera from 15 (71%) of the primary SS patients, but in no PBC patient. Of those PBC patients investigated prospectively with objective tests, four of 11 (36%) had keratoconjunctivitis sicca, and five of 15 (33%) had pathological sialometry results. In contrast, all PBC patients but one (i.e., 14 of 15 or 93%) showed evidence of focal sialadenitis. In immunochemical study of PBC patients, IgM immunoreactivity was found in the stroma, particularly adjacent to excretory ducts and acini in salivary glands (5 of 5), whereas no such IgM deposits were observed in patients with primary SS (3 of 3), nor in healthy controls (n = 20). We conclude that the frequency of anti-SS-A/Ro and anti-SS-B/La antibodies in serum is lower in PBC patients than in patients with primary SS. The incidence of focal sialadenitis is high in PBC, though only one third of the PBC patients studied here showed clinical evidence of glandular dysfunction. With immunochemical techniques, sialadenitis associated with PBC is distinguishable by its significant IgM reaction from sialadenitis in primary SS.