Heterogeneity of RNP and Sm autoantigens in relation to the cell sources and the activated state of the cells

Serologic characteristics in primary biliary cirrhosis associated with sicca syndrome

BACKGROUND

Patients with primary biliary cirrhosis (PBC) may have coincidental sicca syndrome (SS). The frequencies of SS and the occurrence of the Sjögren's-associated anti-Ro and -La antibodies in PBC patients have been reported at widely varying prevalences. This study investigated whether distinctive serologic characteristics are associated with SS in PBC.

METHODS

Forty PBC patients and thirty patients with other types of liver cirrhosis were tested for SS and associated autoantibodies (ANA, AMA 2, anti-Ro, anti-La, anti-U1RNP-A, -C, -68 kD, and rheumatoid factors).

RESULTS

Fourteen PBC patients (35%) complained of sicca symptoms, of whom 10 (25%) had a positive Schirmer-I test, and 7 (17.5%) had serologic characteristics similar to those of Sjögren's syndrome. Anti-52-kD Ro antibodies were positive in seven PBC/SS cases (p < 0.025). There was no anti-Ro positive PBC patient without SS. Three patients with PBC/SS with anti-52-kD Ro and anti-smooth-muscle antibodies developed lung fibrosis. No patient in the other cirrhosis group had SS or its characteristic autoantibody findings.

CONCLUSIONS

It was suggested that PBC and SS are frequently associated. Anti-52-kD Ro antibodies seem to be a characteristic serologic finding for SS in PBC, suggesting their pathogenic role in autoimmune sialadenitis.

Widespread vasculopathy with hemolytic uremic syndrome, perimyocarditis and cystic pancreatitis in a young woman with mixed connective tissue disease. Case report and review of the literature

A 15-year-old girl had severe Raynaud's phenomenon and arthralgias. A high ANA-IF titer was found and undifferentiated connective tissue disease was diagnosed. After 7 years of moderately flaring disease the patient deteriorated and presented with congestive heart failure, pleuropericardial effusion, hemolytic uremic syndrome, proteinuria and moderate hypertension. Autoantibodies against DNA, Sm-protein, and very high titers against U1RNP were detected. Therapy with high steroid doses, a cyclophosphamide pulse and 4 weeks of plasmaphresis with plasma exchange improved the heart, but not the renal condition. Symptomatic pancreatitis became the dominant problem of a progressively consuming process that resulted in the death of the patient. Post-mortem examination revealed widespread vasculopathy with intima proliferation and only minimal fibrosis involving the kidneys, heart and other main organs, including the pancreas. Taken together, the clinical picture was of an overlap between scleroderma and systemic lupus erythemathosus; the serologic and histopathologic findings suggest a diagnosis of a severe form of mixed connective tissue disease (MCTD).

Investigations into Ro-specific antibody-associated congenital cardiac conduction defects

Forty-two babies with different congenital cardiac conduction defects, and in 12 cases the mothers, were tested for autoantibodies to Ro, La, U1RNP and Sm. Ro-specific antibodies were detected most frequently. They were to be found in 16 sera from infants and in 8 maternal serum samples. The occurrence of anti-Ro was associated preferentially with several atrioventricular conduction blocks. The sex relation of anti-Ro associated congenital heart block did not show a typical preference (6 male/10 female). At the time of giving birth, 5 anti-Ro-positive mothers did not have any clinical symptoms of rheumatic autoimmune diseases. Three of them had a first degree atrioventricular block. Our findings indicate that all pregnant women at risk for anti-Ro like connective tissue disease or cardiac conduction defects should be tested for these autoantibodies because of the suspicion of cardiac conduction abnormalities in the offspring. Anti-Ro-positive infants should be examined for structural heart disease by echocardiography.

Development of a solid phase enzyme immunoassay for the detection of anti-Ro autoantibodies

An enzyme immunoassay was developed to detect anti-Ro(SS-A) autoantibodies. Both Ro-antigen components (52 and 60 kD) were purified from a pig spleen extract, using fast protein liquid chromatography (FPLC). Anti-La, anti-RNP, anti-DNA and anti-Sm antibodies do not react to the purified antigen. There was a strong correlation between anti-Ro activity in EIA and the titers in counter immunoelectrophoresis (rs = 0.893). Anti-Ro antibodies were found in 54 (69.2%) of 78 SLE sera by the developed EIA.