SUMMARYThis report contains a description of the cellular localization and kinetics of proinflammatory cytokine expression in murine CIA, a model for rheumatoid arthritis. Tissue cryostat sections of undecalcified paws from type II collagen-immunized DBA/1 mice, taken 1-10 days after the onset of clinical arthritis, were examined for the presence of tumour necrosis factor-alpha (TNF-a), IL-1b and IL-6 using an indirect immunoperoxidase technique. In parallel, interferon-gamma (IFN-g) production by lymph node cells, stimulated in vitro with type II collagen, was assessed as a marker of T cell activity. The main areas of TNF-a, IL-1b and IL-6 expression were in the synovial lining layer and in tissue contiguous with cartilage and bone (the marginal zone), in particular at sites of pannus formation and joint erosion. There was a progressive increase in the number of TNF-a-, IL-1b-and IL-6-positive cells from day 1 to day 10 of arthritis, during which time IFN-g production by CD4+ T cells from draining lymph nodes declined sharply. A further finding of potential significance was that TNF-a was consistently detected at day 1 of arthritis, whereas IL-1b-positive cells were not found until day 3, suggesting that the expression of TNF-a precedes that of IL-1b.

Anti-CD4 ttmet is reported to prevent

Objective. Following recent reports that pathogenic murine anti-DNA antibodies bind to ␣-actinin, it was obviously of interest to assess the ability of human pathogenic anti-double-stranded DNA (anti-dsDNA) antibodies to bind this antigen. Both human monoclonal anti-DNA antibodies and antibodies affinity purified from the sera of patients with systemic lupus erythematosus (SLE) were investigated.Methods. An enzyme-linked immunosorbent assay was established to measure immunoglobulin binding to ␣-actinin. Antibodies binding dsDNA were purified from the sera of SLE patients who either had active renal disease or had never had renal disease. Serum samples were selected at times when the patients' sera exhibited high IgG binding to dsDNA. The binding of supernatants from 3 high-affinity human anti-dsDNA IgG hybridomas (RH14, B3, and DIL-6) and 7 human IgM anti-DNA hybridomas was also investigated.Results. A greater proportion of anti-dsDNA IgGbinding antibodies purified from patients with renal disease bound to ␣-actinin than did those purified from the sera of patients without renal disease. The specificity of binding to the 100-kd ␣-actinin molecule was confirmed by Western blotting. The pathogenic human antibodies RH14 and B3 bound strongly to ␣-actinin, while nonpathogenic DIL-6 bound very weakly. RT84, the IgM antibody that binds dsDNA with the highest affinity, exhibited the greatest binding to ␣-actinin.Conclusion. The results of our study support the findings of previous studies using murine anti-DNA monoclonal antibodies, which suggest that pathogenic anti-dsDNA antibodies cross-react with ␣-actinin.

IntroductionGlomerulonephritis is a major cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Deposition of autoantibodies in the glomeruli plays a key role in the development of lupus nephritis (LN). Different groups have proposed that either anti-nucleosome antibodies or antibodies that bind the intrinsic renal antigen, α-actinin, are central to the pathogenesis of LN. These theories have been based mainly on cross-sectional studies in patients and on experiments in animal models. No previous longitudinal studies have compared the relationships between levels of these antibodies and markers of renal function. We assessed how well anti-α-actinin, anti-nucleosome and anti-double-stranded DNA (anti-dsDNA) antibodies reflected renal outcome measures in patients with new-onset LN followed for up to 2 years.MethodsRenal disease activity was monitored by measuring urine protein/creatinine ratio (PCR), serum albumin and a composite outcome of renal remission. At each time point, anti-nucleosome and anti-α-actinin antibodies were measured by enzyme-linked immunosorbent assay. High-avidity anti-dsDNA antibodies were measured using the Farrzyme assay. We analysed relationships between levels of the three antibodies and between antibody levels and renal outcome measures over time.ResultsLevels of anti-nucleosome and anti-dsDNA were positively correlated with each other (r = 0.6, P = 0.0001) but neither correlated with anti-α-actinin level. At baseline, mean anti-nucleosome levels were higher in patients with LN than in healthy controls (0.32 versus 0.01, P < 0.001). The same was true for anti-dsDNA antibodies (0.50 versus 0.07, P < 0.001) but not for anti-α-actinin (0.33 versus 0.29). Over the follow-up period, anti-nucleosome and anti-dsDNA levels associated positively with urine PCR (P = 0.041 and 0.051, respectively) and negatively with serum albumin (P = 0.027 and 0.032, respectively). Both anti-nucleosome and anti-dsDNA levels were significantly lower during renal remission than when renal disease was active (P = 0.002 and 0.003, respectively). However, there was no relationship between anti-α-actinin levels and urine PCR, serum albumin or remission status.ConclusionsThis prospective longitudinal clinical study is the first to compare levels of anti-nucleosome, anti-dsDNA and anti-α-actinin antibodies in the same patients with SLE. Our results support the concept that, in the majority of patients, anti-nucleosome antibodies play a major role in pathogenesis of LN, in contrast to anti-α-actinin antibodies.

aCL antibodies are associated with the decreased PON activity and reduced NO that may occur in the preclinical phase of APS.