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Objective: To investigate the validity of the global APS score (GAPSS) to predict thrombosis in patients with autoimmune diseases., Methods: This prospective cohort study included consecutive patients with aPL or SLE. aPL, aPS-PT and GAPSS were determined. A Cox proportional hazards model assessed the validity of GAPSS and identified other potential independent predictors of thrombosis., Results: One hundred and thirty-seven patients [43.5 (s.d. 15.4) years old; 107 women] were followed up for a mean duration of 43.1 (s.d. 20.7) months. Mean GAPSS was significantly higher in patients who experienced a thrombotic event compared with those without [10.88 (s.d. 5.06) vs 8.15 (s.d. 5.31), respectively, P = 0.038]. In univariate analysis, age [hazard ratio (HR) = 1.04 (95% CI 1.01, 1.08)] and GAPSS above 16 [HR = 6.86 (95% CI 1.90, 24.77)] were each significantly associated with thrombosis during follow-up, while history of arterial thrombosis [HR = 2.61 (95% CI 0.87, 7.82)] failed to reach significance. Among aPL assays, IgG aPS/PT--a component of the GAPSS--was significantly associated with thrombosis [HR = 2.95 (95% CI 1.02, 8.51)]. In multivariate analysis, GAPSS above 16 remained the only significant predictor of thrombosis [HR = 6.17 (95% CI 1.70, 22.40)]., Conclusion: This first external validation study confirmed that GAPSS can predict thrombosis in patients with aPL and associated autoimmune diseases., (© The Author 2015. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Objectives: This study aimed to estimate the responsiveness to change of a generic [the 36-item Short Form Health Survey (SF-36)] and a specific health-related quality of life questionnaire [the Lupus Quality if Life questionnaire (LupusQoL)] according to SLE patients' self-reported changes in health status., Methods: In a cohort of 185 SLE patients, quality of life (QoL) was measured three times at 3 month intervals by the LupusQoL and SF-36 questionnaires. Anchors for responsiveness were defined by patients' global assessment of disease impact according to changes in a visual analogue scale (VAS), a 7-point Likert scale and a 0-3 scale of five patient-reported symptoms. Mean change and s.d. in worsening and improving patients according to anchors were estimated using mixed models for repeated measures. Standardized response means (SRMs) were calculated in each group., Results: Patients [mean age 39.6 years (s.d. 10.5), mean Safety of Estrogen in Lupus Erythematosus National Assessment-SLEDAI score 2.6 (s.d. 3.5)] answered a total of 515 questionnaires. For the VAS and Likert global anchors, worsening patients showed a significant decrease in all LupusQoL domains except for burden to others, body image and fatigue and all SF-36 domains with low to moderate responsiveness. Improving patients had a significant increase in all LupusQoL domains except for intimate relationship and all SF-36 domains except for physical functioning and global health with low to moderate responsiveness. Regarding similar domains in the SF-36 and LupusQoL, SRMs were higher in LupusQoL domains in improving patients, while SF-36 domains had larger SRMs in worsening patients., Conclusion: Both the SF-36 and LupusQoL were responsive to changes in QoL in SLE patients over a 3 month interval. LupusQoL seems to be more appropriate to measure improvements in QoL., (© The Author 2014. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Objective: To cross-culturally adapt the LupusQoL into French, to test its measurement properties and to further investigate its domain structure., Methods: The cultural adaptation process according to guidelines and pre-testing resulted in the LupusQoL-FR. SLE patients completed the LupusQoL-FR at baseline, 15 days, 3 months and 6 months. Validity was studied through content and construct validity (factorial and Rasch analysis for structural validity, Spearman's correlation and Mann-Whitney tests for external validity). Cronbach's α and intra-class correlation coefficients were computed for reliability. The standardized response mean was computed to evaluate responsiveness., Results: In all, 182 patients, age 39.6 (10.6) years, mostly outpatients [mean SELENA-SLEDAI 2.6 (3.5)] were recruited. Factor analysis with eight imposed factors was very close to the original LupusQoL. A screeplot with parallel analysis showed that LupusQoL domains could be aggregated in two physical and mental scales. Both eight- and two-factor structures showed a good Rasch fit, internal consistency (Cronbach's α: 0.85-0.95), and test-retest reliability (intra-class correlation coefficient 0.79-0.95). External convergent (correlation with SF-36, r=0.59-0.78) and divergent validity (according to SELENA-SLEDAI) were also satisfactory., Conclusion: The LupusQoL-FR is valid to assess quality of life in SLE patients. A two-factor structure of physical and mental aggregated scales is a valid alternative to the original eight-domain structure.

Antiphospholipid antibodies (APL) are usually detected using solid-phase immunoassays, where cardiolipin is the most common capture antigen. Phosholipids are believed to adopt a monolayer organization when coated onto polystyrene after evaporation of the solvent. However, bilayer phospholipids are probably those evidenced as microparticles or cell fragments circulating in vivo under various pathological circumstances. The surface density of monolayer phospholipids on polystyrene is six times lower than that of bilayer phospholipids. In order to assess the influence of phospholipid organization on the detection of APL, we prepared glass microspheres coated with bilayer phospholipids (cardiolipin, phosphatidylcholine, cholesterol). Such lipospheres enabled us to study the binding of antibodies in 1:100 diluted plasma samples from patients with anticardiolipin antibodies of IgG isotype previously diagnosed by ELISA. Among the 39 plasma samples analysed by flow cytometry, 17 showed positive IgG binding to lipospheres. Only four additional samples became positive when adding 20 micrograms/ml apolipoprotein H. The specificity of the binding was demonstrated by complete reversibility with 1.4 microM annexin V and with a large excess of liposomes of the same composition. The absence of correlation between liposphere and ELISA results suggests that different subgroups of antibodies are detected depending on the method. The detection of APL using bilayer phospholipids is an original assay and may represent a more physiopathological approach to the specificity of APL.

Using dithiothreitol (DTT) technique, IgM anti-HLA anti-idiotypic antibodies were detected in a multiparous multitransfused woman. These antibodies were able to inhibit the binding of specific IgG anti-HLA antibodies on their corresponding antigen. The recognized determinants were cross-reactive determinants since they were partially found on anti-HLA antibodies from unrelated individuals. By studying the patient's sera over a period of 2 years, no IgM-IgG switch was observed but the presence of these antibodies was stable in time, despite the disappearance of the idiotypes (anti-HLA antibodies). However, when looking at the patient's earlier serum, it was shown that these IgM anti-idiotypic antibodies were absent from the first available serum. Thus, these anti-idiotypic antibodies seem to behave both like natural and immune antibodies. The incidence of such antibodies in pretransplant patients is discussed.

(2R,5R)-6-heptyne-2,5-diamine (MAP; MDL 72175), a potent irreversible inhibitor of L-ornithine decarboxylase (ODC), possesses immunosuppressive activities in vitro as the result of inhibition of lymphocyte polyamine biosynthesis. The effects of MAP were now studied in vivo in MRL-lpr/lpr female mice, an animal model for human systemic lupus erythematosus (SLE). Administration of MAP (0.2% in drinking water; drug intake: 0.25-0.35 g/kg body weight/day) to female mice for 15 weeks, starting 8 weeks after birth, reduced by 47% the number of spleen cells, retarded development of lymphadenopathy and, at that time, markedly prolonged the survival of the mice. At week 23, MAP reduced plasma IgG concentrations by 50% whereas, in contrast, those of IgM were elevated 1.5-fold. No statistically significant effects of MAP were observed on plasma levels of anti-DNA autoantibodies although serum anti-RNP and anti-Sm titres tended downwards during treatment. Neither glomerular lesions nor proteinuria were improved by MAP administration. Finally chronic administration of MAP for 45 weeks prolonged the median survival time from 29.75 to 35.5 weeks.

The consequences of specific inhibition of polyamine biosynthesis by (2R,5R)-6-heptyne-2,5-diamine (MAP) a potent inhibitor of L-ornithine decarboxylase (ODC), on immunoglobulin (Ig) production were studied in cultured human peripheral blood lymphocytes stimulated with pokeweed mitogen (PWM). MAP inhibits the usual PWM-induced increase of polyamine (putrescine, spermidine and spermine) concentrations and reduces concomitantly cell replication. In parallel with these biochemical effects, IgG and IgM production are diminished, a 95% decrease being observed at 100 microM MAP concentration. That the suppressive effects of the ODC inhibitor result from polyamine deficiency, and not from unrelated pharmacological effects, is demonstrated by the restoration of normal Ig production when 10 microM putrescine or spermidine are added to the culture medium. These findings established that the cellular immunological response can be affected by specific inhibition of polyamine biosynthesis and deserve further consideration both under in vitro and in vivo conditions.

In order to explain long term seronegativity in certain patients with rheumatoid arthritis (RA), we looked for the presence of anti-idiotypic antibodies against rheumatoid factors (RFs). From a patient's serum with classical but seronegative RA, we isolated a low quantity of the IgG fraction which partially recognized polyclonal RF idiotypes. The purified Fab'2 anti-idiotypic antibodies were able to inhibit up to 48% of in vitro RF production by pokeweed mitogen stimulated lymphocytes from a patient's peripheral blood with seropositive RA. The two main conclusions of this study are: (1) this single patient with seronegative RA has serum antibodies directed against RF idiotypes and (2) these anti-idiotypic antibodies could be implicated in the generation of seronegativity.