Both prolonged remission and Lupus Low Disease Activity State are associated with reduced damage accrual in systemic lupus erythematosus

OBJECTIVES: To identify predictors of organ damage and specifically the relationship between prolonged disease remission or low disease activity and damage accrual in a longitudinal cohort of SLE patients. METHODS: Data were prospectively assessed including the occurrence of minor/major flares. Once a year remission and Lupus Low Disease Activity State (LLDAS) were determined retrospectively. A prediction model for damage accrual during follow-up was constructed with backward logistic regression analyses. Secondly, odds ratios (ORs) for damage accrual (SLICC damage index increase of ⩾ 1 during follow-up) were calculated for patients with or without prolonged remission during 5 years, and with or without LLDAS in ⩾ 50% of observations. RESULTS: Data from 183 patients with a median follow-up duration of 5.0 years were analysed. The most significant predictors for damage accrual were: occurrence of ⩾ 1 major flare, mean daily prednisone dose during follow-up and nephrological manifestations at baseline. Prolonged remission was present in 32.5% (38/117) and LLDAS in ⩾ 50% of observations in 64.5% (118/183) of patients. Both the presence of prolonged remission during 5 years and LLDAS in ⩾ 50% of observations were associated with a reduced risk of damage accrual (OR = 0.20, 95% CI: 0.07, 0.53, P = 0.001 and OR = 0.52, 95% CI: 0.28, 0.99, P = 0.046, respectively). CONCLUSION: This cohort study shows that prolonged remission and LLDAS were associated with an improved outcome, as determined by yearly assessments. In order to improve the outcome in SLE patients, future studies should investigate whether these targets can be reached actively with therapeutic strategies

Anti-hinge antibodies recognize IgG subclass- and protease-restricted neoepitopes

Anti-hinge Abs (AHAs) target neoepitopes exposed after proteolytic cleavage of IgG. In this study, we explored the diversity of protease- and IgG subclass-restricted AHAs and their potential as immunological markers in healthy donors (HDs) and patients with rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE). AHA reactivity against IgG-degrading enzyme of Streptococcus pyogenes (IdeS)- or pepsin-generated F(ab′)2 fragments of all four human IgG subclasses was determined. AHA reactivity against one or more out of eight F(ab′)2 targets was found in 68% (68 of 100) of HDs, 69% (68 of 99) of SLE patients, and 81% (79 of 97) of RA patients. Specific recognition of hinge epitopes was dependent on IgG subclass and protease used to create the F(ab′)2 targets, as confirmed by inhibition experiments with F(ab′)2 fragments and hinge peptides. Reactivity against IdeS-generated F(ab′)2 targets was found most frequently, whereas reactivity against pepsin-generated F(ab′)2 targets better discriminated between RA and HDs or SLE, with significantly higher AHA levels against IgG1/3/4. In contrast, AHA levels against pepsin-cleaved IgG2 were comparable. No reactivity against IdeS-generated IgG2-F(ab′)2s was detected. The most discriminatory AHA reactivity in RA was against pepsin-cleaved IgG4, with a 35% prevalence, ≥5.8-fold higher than in HDs/SLE, and significantly higher levels (p < 0.0001). Cross-reactivity for F(ab′)2s generated from different IgG subclasses was only observed for subclasses having homologous F(ab′)2 C termini (IgG1/3/4). For IgG2, two pepsin cleavage sites were identified; anti-hinge reactivity was restricted to only one of these. In conclusion, AHAs specifically recognize IgG subclass- and protease-restricted hinge neoepitopes. Their protease-restricted specificity suggests that different AHA responses developed under distinct inflammatory or infectious conditions and may be markers of, and participants in, such processes