THE MOLECULAR BASIS OF THE SSA/Ro ANTIGENS AND THE CLINICAL SIGNIFICANCE OF THEIR AUTOANTIBODIES

The SSA/Ro antigens are nuclear and cytoplasmic polypeptideswhich serve as autoantigens in systemic lupus erythemato-sus(SLE) and Sjögren's syndrome (SS). They contain two majorisoforms of 60 and 52 kD. The former is the native antigen whilethe latter is a major autoantigen in its denatured form. A thirdprotein of 46 kD termed ‘calreticulin-Ro’ is anautoantigen found in the sera of some patients with SLE. However,it is probably unrelated to the SSA/Ro system. The clinicalrelevance of anti SSA/Ro antibodies in rheumatic diseases hasalso been considered. Initially these antibodies were thoughtto be an epiphenomenon of autoimmune diseases. Recent studieshave shown that they are associated with specific clinical manifestationsand disease subsets. Furthermore, animal models have demonstratedthat they may enhance tissue damage. It seems that anti-SSA/Roantibodies may play a role in the pathogenicity of SLE and SS. KEY WORDS: SSA/Ro antigen, Autoantibodies, Systemic lupus erythematosus, Sjögren's syndrome     

The usefulness of immunofluorescent tests in pemphigus patients in clinical remission

Direct and indirect immunofluorescent studies (DIF, IIF) were performed on 24 pemphigus vulgaris patients who were in a state of clinical remission. The tests were repeated after an interval of 6 months. All the patients were on maintenance therapy with oral prednisone. The DIF in eight patients showed negative results among whom seven remained negative. Six patients out of 24 showed weakly positive fluorescence and ten patients showed strong positive fluorescence. The IIF was negative in 17 patients and positive in seven patients who also showed positive DIF. During a follow-up period of 20 months, one of eight patients with negative DIF relapsed compared with two of six patients with weak positive DIF and five of 10 patients with strong DIF. Five patients with strong DIF for IgG also had C3, of whom three relapsed, compared with five of 19 patients who were negative for C3. Four of seven patients with positive IIF relapsed compared with four of 17 with negative IIF. It is suggested that repeated DIF tests in pemphigus patients, who are in clinical remission, may serve as an indicator for the immunological activity and be of help in the management of these cases.     

AUTOANTIBODIES IN FAMILIAL MEDITERRANEAN FEVER (RECURRENT POLYSEROSITIS)

The presence of autoantibodies in our familial Mediterraneanfever (FMF) patients was investigated using various immunologicaltechniques. Immunofluorescence screening of 50 FMF sera revealedonly one positive for antinuclear antibodies. ELISA assay andnitrocellulose filter assay revealed no difference between FMFsera and healthy controls with regard to the presence of anti-dsDNAantibodies. In Western blotting using HeLa cell extract, FMFpatients' sera neither detected anti-Sm, RNP, SSA/Ro, SSB/Laantibodies nor any new common band. These findings suggest thatit is unlikely that FMF belongs to the family of the autoimmune‘collagen’ diseases. KEY WORDS: Immunofluorescence, ELISA, Western blotting, Antinuclear antibodies, FMF     

MALIGNANT MELANOMA IN TURNER'S SYNDROME

A 45-year-old woman presented with a 2-week history of weakness with rapidly progressing abdominal distention. Two weeks previously she had an abdominal ultrasound that showed no evidence of ascites or malignant changes.
The patient was known to suffer from Turner's syn-drome 45XO/46XX and Hashimoto's thyroiditis for which she was treated with L-thyroxine. She also had numerous nevi, some of which were biopsied recently and interpreted as having no malignant features.
On admission, the patient complained of weakness and abdominal discomfort. She was of short stature and was pale. Her secondary sexual characteristics were fully devel-oped. Many pigmented nevi were scattered over her skin, without clinical signs of malignant transformation. Fundo-scopy showed no signs of malignancy in the choroid layer. The abdomen was tense and edematous. Breast examina-tion was normal. An ECG and chest x-rays were also within normal limits. Computerized tomography showed a large amount of fluid with small masses spreading in the peri-toneal cavity. Aspiration of the abdominal fluid revealed ma-lignant cells that stained positively with S-100, melanoma-specific antigens, and with Masson-Fontana (Fig. 1).