Antibodies reacting with ribosomal ribonucleoprotein in connective tissue diseases.

Precipitating antibody to an antigen present in cytoplasm was detected in the sera of 7 patients with systemic lupus erythematosus, 1 patient with an overlap toid arthritis, and 1 patient with mixed connective tissue disease. By physicochemical and enzymatic studies, the antigen was shown to have the properties of ribosomal ribonucleoprotein (gamma-RNP). Cytoplasmic staining in immunofluorescence was observed with all the 9 sera containing antibodies to gamma-RNP. In certain cases, cytoplasmic staining was associated with nucleolar staining. Antibody to gamma-RNP is different in immunologic specificity and clinical significance from antibody to nuclear RNP and is present primarily in patients with systemic lupus erythematosus.     

Auto antibodies in the cerebrospinal fluid of patients with systemic lupus erythematosus

Autoantibodies may play an important role in the pathogenesis of central nervous system (CNS) disease in systemic lupus erythematosus (SLE). We obtained cerebrospinal fluid (CSF) and, in some cases, sera from 19 SLE patients with CNS lupus and from 12 SLE patients without CNS lupus. Autoantibodies to saline soluble cellular antigens were detected in the CSF of lupus patients and reflected those present in the serum. These antibodies were distinct from the previously described antineuronal antibodies. Analysis of the fine specificities of the anti-saline soluble cellular antigen antibodies revealed that the antiribosomal P protein antibody was present in 4 of 4 patients with lupus psychosis and was enriched in the CSF of 1 patient. Sera containing antiribosomal P protein showed prominent cytoplasmic staining of human cortical neurons, as well as an epithelial cell substrate. These observations, together with the increase in intrathecal IgG synthesis detected in 71% of patients tested, suggest that several populations of antibodies may contribute to the enhanced immunologic activity in the CSF of CNS lupus patients.     

Autoantibodies in the cerebrospinal fluid of patients with systemic lupus erythematosus

Autoantibodies may play an important role in the pathogenesis of central nervous system (CNS) disease in systemic lupus erythematosus (SLE). We obtained cerebrospinal fluid (CSF) and, in some cases, sera from 19 SLE patients with CNS lupus and from 12 SLE patients without CNS lupus. Autoantibodies to saline soluble cellular antigens were detected in the CSF of lupus patients and reflected those present in the serum. These antibodies were distinct from the previously described antineuronal antibodies. Analysis of the fine specificities of the anti-saline soluble cellular antigen antibodies revealed that the antiribosomal P protein antibody was present in 4 of 4 patients with lupus psychosis and was enriched in the CSF of 1 patient. Sera containing antiribosomal P protein showed prominent cytoplasmic staining of human cortical neurons, as well as an epithelial cell substrate. These observations, together with the increase in intrathecal IgG synthesis detected in 71% of patients tested, suggest that several populations of antibodies may contribute to the enhanced immunologic activity in the CSF of CNS lupus patients.     

Antibodies to nucleic acids in human and murine lupus.

Antibodies to nucleic acid are present in the sera of patients with systemic lupus erythematosus and in the sera of NZB/NZW F1 mice, an animal model for human systemic lupus erythematosus. Sera can be fractionated by sucrose-density gradient ultra-centrifugation and individual fractions assayed for binding of radioactive DNA, RNA or DNA: RNA hydridsive DNA, RNA or DNA: RNA hybrids. Immunoglobulin determinations can also be performed on these fractions. Antinucleic acid antibody activity can be recovered both in the 19S IgM and 7S IgG fractions. Individual variations from patient to patient suggest that more detailed analysis of immunoglobulin classes may provide insights into the pathogenesis of lupus.     

Determination of autoantibodies to annexin XI in systemic autoimmune diseases

Annexin XI, a calcyclin-associated protein, has been shown to be identical to a 56,000 Da antigen recognized by antibodies found in sera from patients suffering from systemic autoimmune diseases. In this work hexahistidine-tagged recombinant annexin XI (His6- rAnn XI) was used as antigen in ELISA experiments for determination of autoantibodies to annexin XI in sera of patients with systemic rheumatic autoimmune diseases. Immunoblotting with HeLa cell extract and with His6-rAnn XI as antigen was used for confirmation of positive ELISA results. We found eleven anti-annexin XI positive sera (3.9%) out of 282 sera from patients with systemic rheumatic diseases. The highest number of annexin XI positive sera were found in primary antiphospholipid syndrome (3/17), and in subacute lupus erythematosus (1/6), while lower frequencies of positive sera were found in patients with systemic sclerosis (5/137), rheumatoid arthritis (1/21), and systemic lupus erythematosus (1/58). Sera from healthy donors and patients with chronic infections were negative, except for one Salmonella typhimurium antibody positive serum. Autoantibodies to annexin XI were found to relate to thrombosis, but not to other clinical or laboratory features. A relation between antibodies to annexins and thrombosis has so far only been known for annexin V.     

The immunologic diagnosis of chronic active "autoimmune" hepatitis: distinction from systemic lupus erythematosus

We have evaluated the immunologic characteristics often associated with systemic lupus erythematosus in a series of patients with a variety of different liver diseases. Antibody to double-stranded DNA as measured by the Farr assay was detected frequently in patients with various forms of liver disease. No patient with liver disease, including those with a presumed immunologic etiology, was found to have antibody to double-stranded DNA using more specific assays. Other immunologic phenomena such as the presence of immunofluorescent staining at the dermal-epidermal junction in the lupus band test, circulating immune complexes and the presence of antinuclear antibody were present in a number of patients with different forms of liver disease. The absence of antibody to double-stranded DNA in patients with liver disease suggests that there may be a true immunologic distinction between systemic lupus erythematosus and chronic active ("lupoid") hepatitis.     

Anticytoskeletal autoantibodies in the connective tissue diseases

The sera of 103 patients with connective tissue diseases were studied for the presence of anticytoskeletal antibodies by using an indirect immunofluorescence method. PTK2 cells fixed with paraformaldehyde and digitonin were used as substrate. Antibodies to intermediate filaments were detected in sera of 85.7% of polymyositis/dermatomyositis (PM/DM), 62.8% of systemic sclerosis, 54.5% of rheumatoid arthritis, and 37.5% of systemic lupus erythematosus patients, and in 42.5% of normal sera. High titers of these antibodies, which were IgM, were present in 30% of patients' and 5% of normal sera. Antibodies to microfilaments were present in 11.6% of patients' sera and absent in all control sera. These antibodies were IgM or IgG. The switch from an IgM to an IgG antibody was observed in 1 patient. An IgG antibody to the spindle poles and midbody of mitotic cells was present in the serum of 1 patient with the CREST syndrome (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, telangiectasias). Antibodies to intermediate filaments and to microfilaments occur commonly in the connective tissue diseases, particularly in PM/DM, and are not detected with substrates or fixation methods used in routine antinuclear antibody testing.     

High titer of antibody to the Epstein-Barr virus membrane antigen in sera from patients with rheumatoid arthritis and systemic lupus erythematosus

Sera from patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) contained more antibody to the Epstein-Barr virus membrane antigen (EBV MA) than sera from healthy controls. Since antibody titer to EBV MA closely correlates with viral neutralization, it was inferred that these patients were frequently exposed to infectious EBV, producing high titers of neutralizing antibody.     

Prospective analysis of antiribonucleoprotein antibodies in systemic lupus erythematosus.

A prospective analysis of 50 successive patients with systemic lupus erythematosus, seen over a 4-year period, has been completed. 336 sera were examined for the presence of antibody to ribonucleoprotein using a counterimmunoelectrophoresis assay. Antibody was present in the sera of 16% of patients and was detectable in about the same titre throughout the course of the disease. The presence of the antibody did not appear to identify a subgroup of lupus patients with individual clinical characteristics.     

The binding of antihistone antibodies to Crithidia luciliae kinetoplasts is growth cycle-dependent

The Crithidia luciliae immunofluorescence (CLIF) assay is widely used to test for native DNA (nDNA) antibodies in the diagnosis and management of systemic lupus erythematosus. However, sera from patients with drug-induced lupus erythematosus or rheumatoid arthritis, which should not contain nDNA antibodies, occasionally react with the CL kinetoplast. We examined 36 sera from patients with systemic lupus erythematosus, rheumatoid arthritis, Sj?gren's syndrome, and drug-induced lupus erythematosus, who had positive CLIF tests. All 36 sera were also antinuclear antibody-positive with homogeneous and/or peripheral staining patterns on mouse kidney substrates. After hydrochloric acid extraction of the CL smears to remove histone and other nuclear protein antigens, 14 of the 36 sera no longer produced a positive result on the CLIF test. Ten of these 14 sera again gave a positive CLIF result after the hydrochloric acid-extracted Crithidia substrate had been reconstituted with purified histone. These studies demonstrated that kinetoplast binding was due to antihistone antibodies in at least 10 of 36 initially CLIF-positive sera. Antihistone antibodies were then purified with a histone-affinity column, and these purified antibodies were reactive with CL kinetoplasts. Thus, the CLIF test is not specific for nDNA antibodies. Additional studies using CL from different days of culture indicated that histone antigen expression in the CL kinetoplast was a function of the life cycle of this organism and is most readily detected 2 days after initiation of culture.     

Survivorship in systemic lupus erythematosus. effect of antibody to extractable nuclear antigen

The course of 81 patients with systemic lupus erythematosus (SLE) who had sera tested for antibody to extractable nuclear antigen (ENA) was studied to determine the effect of the presence of antiENA antibody on survivorship. There were no differences in percent survival between the patients with and without antibody to ENA or those with and without antibody to the ribonucleoprotein (RNP) component of ENA. We conclude that there is no prognostic advantage to the presence of either antiENA or antiRNP antibody in patients with SLE.     

A novel antinuclear antibody associated with a lupus-like paraneoplastic syndrome

The association of malignancy with lupus-like syndromes is rare, and the relation between these two processes is uncertain. A 71-year-old woman who presented with serositis, Raynaud phenomenon, and positive results on an antinuclear antibody test was initially thought to have systemic lupus erythematosus but was found to have ovarian adenocarcinoma. A unique sparsely speckled antinuclear antibody pattern was seen. The patient's sera reacted to novel antigens with six bands of 100, 80-78, 48, and 17 kD on Western blots not typical of reactivity for sera from patients with systemic lupus erythematosus.     

Protein losing enteropathy due to systemic lupus erythematosus.

We report the case of a 29 year old woman with a protein losing enteropathy caused by systemic lupus erythematosus presenting with periorbital oedema. Only three other cases of protein losing enteropathy due to systemic lupus erythematosus have been described, two of which were thought to be because of a primary enteropathy, although the exact pathogenesis was unknown. We suggest that both the protein losing enteropathy and periorbital oedema in this patient were because of increased capillary permeability to serum albumin, as a result of products of plasma C3 conversion which were present in large amounts. It is also of interest that the antigen/antibody system in this patient was RNP/anti-RNP and that DNA antibodies were not detected. This patient falls into a subset of systemic lupus erythematosus in which anti-DNA antibodies are not present, some of which appear to have a more favourable prognosis.     

Altered immune response to glycine-rich sequences of Epstein-Barr nuclear antigen-1 in patients with rheumatoid arthritis and systemic lupus erythematosus

Prior studies have shown that patients with rheumatoid arthritis (RA) have an increased number of circulating Epstein-Barr virus-infected B lymphocytes and elevated titers of antibody to Epstein-Barr nuclear antigen-1 (EBNA-1), the major nuclear antigen expressed in latently infected B cells. However, it is not known whether antibodies from RA patients recognize the same epitopes as antibodies from normal subjects. are directed at the glycine-alanine repeating region of the molecule. Antibodies specific for this region are also somewhat more prevalent in RA patients than in normal subjects. A panel of synthetic peptides derived from EBNA-1 was used to analyze the immune response to antigenic epitopes outside the glycine-alanine region, using the peptides as solid-phase antigen. Sera from RA patients and from systemic lupus erythematosus patients contained elevated levels of IgG antibodies to 2 non-glycine-alanine peptide and to 3 non-glycine-alanine peptides, respectively. Two of the 3 peptides are glycine-rich, but antibodies that react with them are distinct from each other, as well as from those that react with the glycine-alanine epitope. Eight other peptides from the C-terminal portion of EBNA-1 either do not react with sera or show no difference between normal subjects and patient groups. The antibodies to the glycine-alanine peptide are enriched with kappa light chains, whereas antibodies to epitopes outside the glycine-alanine region are not so restricted among kappa and lambda light chains. Thus, RA patients and systemic lupus erythematosus patients have different antibody responses than do normal subjects, both quantitatively and qualitatively.     

Anti-alpha-fodrin autoantibody is an early diagnostic marker for childhood primary Sjögren's syndrome

OBJECTIVE: alpha-fodrin is a recently identified autoantigen associated with adult primary Sj?gren's syndrome (SS). We tested whether anti-alpha-fodrin antibody could also be used as a diagnostic marker for childhood SS. METHODS: We performed immunoblot analysis of sera from 7 patients with childhood primary SS using glutathione-S-transferase alpha-fodrin fusion protein as an antigen. RESULTS: Anti-alpha-fodrin antibody was detected in sera from all 7 patients with childhood primary SS, 2 of 4 with secondary SS, and one of 7 with systemic lupus erythematosus, but in no other healthy controls. CONCLUSION: The anti-alpha-fodrin autoantibody was detected before anti-SSA or SSB antibody became positive; thus anti-alpha-fodrin antibody could be a useful marker for the early diagnosis of SS.     

Occlusion of small hepatic veins associated with systemic lupus erythematosus with the lupus anticoagulant and anti-cardiolipin antibody

We report the case of a woman with lupus anticoagulant-positive systemic lupus erythematosus who developed small hepatic vein occlusion. Since the age of 34, she had been known to have hepatomegaly. A definitive diagnosis of systematic lupus erythematosus was made eight years later. Histological evaluation of the liver biopsy specimen was not fully diagnostic of prominent hepatomegaly during this period. Occlusion of the small hepatic veins was confirmed by hepatic venography, but the lumen of the large hepatic veins showed a smooth appearance. The lupus anticoagulant and anti-cardiolipin antibody were both positive. Since a high incidence of thromboembolic diseases in patients with the lupus anticoagulant or anti-cardiolipin antibody has been reported, the presence of this type of anticoagulant may provide an explanation for hypercoagulability and subsequent development of hepatic vein thrombosis in this patient. This is the first report of a patient with systemic lupus erythematosus who developed an occlusion of small hepatic veins attributable to the lupus anticoagulant and anticardiolipin antibody. This case suggested that a systematic search for hepatic vein occlusion should be made in patients with systemic lupus erythematosus who have developed inexplicable hepatomegaly, especially in those with positive tests for the lupus anticoagulant and/or anti-cardiolipin antibody.     

Influenza immunization in systemic lupus eruthematosus. A double-blind trial.

Forty patients with systemic lupus erythematosus randomly received inactivated bivalent (A/NJ and A/Victoria) influenza vaccine or saline in a double-blind study. During 20 weeks of follow-up, no deterioration in major organ function or increase in disease flares was observed in the immunized group as compared with the group that received saline. Preimmunization antibody titers to A/Victoria were lower in the 40 patients with lupus erythematosus than in age-matched control subjects. Response to immunization, as measured by serum antibody titers, was also lower in the patients with lupus erythematosus, indicating that immune responses must be evaluated on an individual patient basis. Nevertheless, influenza vaccination can be safely carried out in patients with systemic lupus erythematosus.     

Presentation of autoantibody to proliferating cell nuclear antigen in patients with chronic hepatitis B and C virus infection

OBJECTIVES: To study the association of antibodies to proliferating cell nuclear antigen (PCNA) in patients with chronic hepatitis B (HBV) and C (HCV) virus infection. METHODS: Sera from 243 patients with chronic HBV infection; 379 patients with chronic HCV infection; 80 patients with systemic lupus erythematosus (SLE); 28 patients with rheumatoid arthritis; 15 patients with Sjogren's syndrome; eight with polymyositis; eight with primary biliary cirrhosis; and 33 healthy control subjects were tested for the presentation of anti-PCNA antibodies by enzyme linked immunosorbent assay (ELISA) and immunoblotting using recombinant PCNA as antigen. The distribution of immunoglobulin isotypes of anti-PCNA antibody was measured by ELISA assay. RESULTS: By ELISA, anti-PCNA antibodies were detected in 30 (12.3%) patients with chronic HBV infection, 71 (18.7%) patients with chronic HCV infection, and five (6.3%) patients with SLE. The inhibition of binding with these sera by purified PCNA was shown to exceed 71%. By immunoblotting, the frequency of anti-PCNA in patients with chronic HBV and HCV infection was 17 of 243 (7%) and 41 of 379 (11%), respectively. Absorption studies on indirect immunofluorescence showed the typical nuclear speckled staining pattern by anti-PCNA sera was abolished by preincubation of sera with PCNA. Anti-PCNA antibody was not detected in sera from patients with autoimmune diseases except SLE. Anti-PCNA antibodies in patients with chronic HBV and HCV infection were predominantly IgG. CONCLUSION: These data suggest that anti-PCNA antibody are also present in patients with chronic HBV and HCV infection. Anti-PCNA antibody may not be specific for SLE.     

Functional asplenia in systemic lupus erythematosus

A patient with inactive systemic lupus erythematosus was successfully treated for pneumococcal sepsis complicated by disseminated intravascular coagulation, shock, renal failure, and functional asplenia. Functional asplenia was diagnosed from the total absence of uptake of intravenously administered 99mtechnetium-labeled sulfur colloid. Ten similar cases of functional asplenia occurring in patients with systemic lupus erythematosus were noted in a review of the literature. Six of these cases, including the current report, were complicated by pneumococcal (5) or salmonella (1) sepsis. The patient presented here had an excellent antibody response to pneumococcal vaccination. Spleen scan abnormalities fully reversed at 1 year. Although functional asplenia is a rare event in systemic lupus erythematosus, it appears to predispose to severe septic complications.