Antibodies to new cytoplasmic autoantigens: anti-ja, a potential marker for disease activity in systemic lupus erythematosus

We describe new autoantibodies which recognize two cytoplasmic proteins of 30 and 26 kDa. They were detected by Western blot analysis in the sera of 6 of 79 randomly selected systemic lupus erithematosus (SLE) patients and are denoted anti-JA antibodies. This antibody specificity is different from the previously described lupus autoantibodies, anti-P and anti-S10. The targeted autoantigens are trypsin sensitive, and resistant to RNase and DNase treatment. The binding to the antigens was not modified when reticulocyte ribosomes were prepared with protease inhibitors indicating that these are primary antigen and not degradation products. Several lines of evidence suggest that these proteins are almost certainly part of the ribosome. Anti-JA reactivity was not observed in the sera from 60 patients with other autoimmune diseases or from normal individulas. In contrast, 55% of lupus sera selected for a high titer of anti-ds DNA (double stranded DNA) and LE cells were also anti-JA positive. Anti-JA antibodies may be useful as a specific serological marker for disease activity in SLE. The strong association with anbti-ds-DNA antibodies and LE cell in the sera of SLE patients requires further study

Antyphospholipid antibodies in syphilis

1. An enzyme-linked immunosorbent assay was used to determine the phospholipid specificity of antibodies in sera from 35 syphilis patients. 2. Based on the cross-reaction obtained aginst a mixture of cardiolipin, phosphatidylcholine and holesterol that is standard for flocculation tests according to the Venereal Disease Research Laboratory (CECON, Säo Paulo, Brazil), all 35 patients tested positive for antibodies of the IgG class whereas 13 (37%) also had IgM antibodies for the same mixture of lipids. IgG antibodies to cardiolipin were demonstrated in 2 patients (6%) and IgM antibodies in 5 (15%). Significant levels of IgG anti-phosphatidylcholine were detected in 3 patients (9%) and IgM antibodies in 4(11%). IgG anti-phosphatidylethanolamine antibodies were found in 1 patient (3%) and IgM antibodies in 3(9%). Antibody binding to cardiolipin plus cholesterol or cardiolipin plus phosphatidycholine was as effective as when the standard mixture of all 3 lipids was used. 3. A comparison with serum from systemic lupus erythematosus patients and inhibition studies using liposomes o cardiolipin or the mixture of 3 lipids suggests that there are at least 3 groups of anticardiolipin antibodies