Jacques Tebib

Retraction: Interleukin 17 acts in synergy with B cell-activating factor to influence B cell biology and the pathophysiology of systemic lupus erythematosus

Nicole Boucheron, Roland Tschismarov, Lisa Goeschl, Mirjam A Moser, Sabine Lagger, Shinya Sakaguchi, Mircea Winter, Florian Lenz, Dijana Vitko, Florian P Breitwieser, Lena Müller, Hammad Hassan, Keiryn L Bennett, Jacques Colinge, Wolfgang Schreiner, Takeshi Egawa, Ichiro Taniuchi, Patrick Matthias, Christian Seiser& Wilfried Ellmeier Nat. Immunol. 15, 439–448 (2014); published online 30 March 2014; corrected after print 6 June 2014

Langerhans cell histiocytosis reveals a new IL-17A- dependent pathway of dendritic cell fusion

IL-17A is a T cell–specific cytokine that is involved in chronic inflammations, such as Mycobacterium infection, Crohns disease, rheumatoid arthritis and multiple sclerosis. Mouse models have explained the molecular basis of IL-17A production and have shown that IL-17A has a positive effect not only on granuloma formation and neurodegeneration through unknown mechanisms, but also on bone resorption through Receptor activator of NF-κB ligand (RANKL) induction in osteoblasts. Langerhans cell histiocytosis (LCH) is a rare disease of unknown etiology, lacking an animal model, that cumulates symptoms that are found separately in various IL-17A–related diseases, such as aggressive chronic granuloma formation, bone resorption and soft tissue lesions with occasional neurodegeneration. We examined IL-17A in the context of LCH and found that there were high serum levels of IL-17A during active LCH and unexpected IL-17A synthesis by dendritic cells (DCs), the major cell type in LCH lesions. We also found an IL-17A–dependent pathway for DC fusion, which was highly potentiated by IFN-γ and led to giant cells expressing three major tissue-destructive enzymes: tartrate resistant acidic phosphatase and matrix metalloproteinases 9 and 12. IFN-γ expression has been previously documented in LCH and observed in IL-17A–related diseases. Notably, serum IL-17A–dependent fusion activity correlates with LCH activity. Thus, IL-17A and IL-17A–stimulated DCs represent targets that may have clinical value in the treatment of LCH and other IL-17A–related inflammatory disorders.

Infliximab therapy in rheumatoid arthritis and ankylosing spondylitis-induced specific antinuclear and antiphospholipid autoantibodies without autoimmune clinical manifestations: a two-year prospective study

Treatment of rheumatoid arthritis (RA) with infliximab (Remicade®) has been associated with the induction of antinuclear autoantibodies (ANA) and anti-double-stranded DNA (anti-dsDNA) autoantibodies. In the present study we investigated the humoral immune response induced by infliximab against organ-specific or non-organ-specific antigens not only in RA patients but also in patients with ankylosing spondylitis (AS) during a two-year followup. The association between the presence of autoantibodies and clinical manifestations was then examined. The occurrence of the various autoantibodies was analyzed in 24 RA and 15 AS patients all treated with infliximab and in 30 RA patients receiving methotrexate but not infliximab, using the appropriate methods of detection. Infliximab led to a significant induction of ANA and anti-dsDNA autoantibodies in 86.7% and 57% of RA patients and in 85% and 31% of AS patients, respectively. The incidence of antiphospholipid (aPL) autoantibodies was significantly higher in both RA patients (21%) and AS patients (27%) than in the control group. Most anti-dsDNA and aPL autoantibodies were of IgM isotype and were not associated with infusion side effects, lupus-like manifestations or infectious disease. No other autoantibodies were shown to be induced by the treatment. Our results confirmed the occurrence of ANA and anti-dsDNA autoantibodies and demonstrated that the induction of ANA, anti-dsDNA and aPL autoantibodies is related to infliximab treatment in both RA and AS, with no significant relationship to clinical manifestations.

B cell activation biomarkers as predictive factors for the response to rituximab in rheumatoid arthritis: A six-month, national, multicenter, open-label study†

OBJECTIVE To examine whether serum B cell markers can predict response to rituximab, a B cell-depleting monoclonal antibody, in patients with refractory rheumatoid arthritis (RA). METHODS This rituximab re-treatment dose study (SMART [eSsai MAbthera sur la dose de Re-Traitement]) involved 208 patients with refractory RA. Serum markers of B cell activation (anti-cyclic citrullinated peptide [anti-CCP] antibodies, rheumatoid factor [RF], serum IgG, IgA, and IgM levels, serum κ and λ free light chains, and serum BAFF) were assessed before the first rituximab cycle (1,000 mg on days 1 and 15). Univariate and multivariate analyses were performed to identify factors associated with a European League Against Rheumatism (EULAR) response at 24 weeks. RESULTS There were 149 responders (72%). Two baseline factors were associated with a EULAR response at 24 weeks in multivariate analysis: the presence of anti-CCP antibodies or RF (odds ratio 3.5 [95% confidence interval 1.6-7.6]) and a serum IgG concentration above normal (odds ratio 2.11 [95% confidence interval 1.02-4.33]), with synergy between them (odds ratio 6.0 [95% confidence interval 2.2-16.2]). CONCLUSION The presence of RF or anti-CCP antibodies and elevated IgG are 2 simple biomarkers that can be used routinely before therapy to predict response to rituximab in patients with refractory RA.

The shared epitope is a marker of severity associated with selection for, but not with response to, infliximab in a large rheumatoid arthritis population

Objective: To determine whether joint destruction, indication for, and response to infliximab in rheumatoid arthritis are associated with the shared epitope (SE) or selected cytokine gene polymorphisms (interleukin (IL) 1B, IL1-RN, and tumour necrosis α). Methods: In a large rheumatoid arthritis population of 930 patients from the same area (Rhône-Alpes, France), patients with (n = 198) or without infliximab treatment (n = 732) were compared according to their genetic status. Clinical, biological, and radiological data were collected. Typing for SE status and cytokine polymorphisms was carried out using enzyme linked oligosorbent assay. Statistical analysis was by χ2 testing and calculation of odds ratios (OR). Results: A dose relation was observed between the number of SE copies and joint damage in the whole rheumatoid population (OR, 1 v 0 SE copy = 2.38 (95% confidence interval, 1.77 to 3.19), p<0.001; OR 2 v 0 SE copy = 3.92 (2.65 to 5.80), p<0.001. The SE effect increased with disease duration but was not significant before two years. Selection for infliximab treatment (n = 198) was associated with increased disease activity, joint damage, and the presence of the SE with a dose effect. In all, 66.2% patients achieved an ACR20 improvement. No clinical or genetic factors were able to predict the clinical response to infliximab. Conclusions: This post-marketing study in a large cohort of rheumatoid arthritis patients indicates a linkage between rheumatoid arthritis severity, selection for treatment with infliximab, and the presence and dose of the SE.

Blood Memory B Cells Are Disturbed and Predict the Response to Rituximab in Patients With Rheumatoid Arthritis

OBJECTIVE To examine blood B cell subsets in patients with rheumatoid arthritis (RA) prior to B cell depletion therapy and to assess their potential as predictors of clinical response to rituximab (RTX). METHODS Blood B cell subsets were assessed by flow cytometry in 208 RA patients included in an RTX retreatment study (assessed prior to RTX treatment) and in 47 age-matched controls. Expression of BAFF receptor (BAFF-R) on B cells and serum B cell biomarkers was also measured. B cell subsets and BAFF-R expression were compared between RA patient and control populations. Univariate and multivariate analyses were performed to identify baseline factors associated with a European League Against Rheumatism response 24 weeks after 1 cycle of RTX. RESULTS Mean ± SD counts of both CD27- naive and CD27+ memory B cells were decreased in RA patients (188.6 ± 121.4/mm(3)) compared with controls (257.3 ± 154.1/mm(3)) (P = 0.001) and were partially restored in patients treated with methotrexate (MTX) plus anti-tumor necrosis factor compared with patients treated with MTX alone. Within the CD27+ memory B cells, the CD27+IgD- switched memory subtype was selectively decreased, irrespective of treatment. The frequency of CD27+ memory B cells correlated inversely with levels of several B cell activation biomarkers in RA. Serum BAFF level and BAFF-R expression was comparable in RA patients and controls. A low baseline CD27+ memory B cell frequency was associated with a greater clinical response to RTX (odds ratio 0.97 [95% confidence interval 0.95-0.99], P = 0.0015). CONCLUSION In B cell depletion therapy-naive RA patients, a low frequency of CD27+ memory B cells correlated with levels of serum B cell activation biomarkers and may predict response to RTX. These results suggest that low memory B cell frequency may be indicative of a B cell-driven RA subtype that is more sensitive to B cell depletion therapy.

Apolipoprotein A-I and platelet factor 4 are biomarkers for Infliximab response in rheumatoid arthritis

Objectives: The use of biologicals such as infliximab has dramatically improved the treatment of rheumatoid arthritis (RA). However, factors predictive of therapeutic response need to be identified. A proteomic study was performed prior to infliximab therapy to identify a panel of candidate protein biomarkers of RA predictive of treatment response. Methods: Plasma profiles of 60 patients with RA (28 non-responders (as defined by the American College of Rheumatology 20% improvement criteria (ACR20)) negative and 32 responders (ACR70 positive) to infliximab) were studied by surface enhanced laser desorption/ionisation time-of-flight mass spectrometry (SELDI-TOF MS) technology on two types of arrays, an anion exchange array (SAX2) and a nickel affinity array (IMAC3-Ni). Biomarker characterisation was carried out using classical biochemical methods (purification by ammonium sulfate precipitation or metal affinity chromatography) and identification by matrix assisted laser desorption/ionisation time-of-flight (MALDI-TOF) MS analysis. Results: Two distinct protein profiles were observed on both arrays and several proteins were differentially expressed in both patient populations. Five proteins at 3.86, 7.77, 7.97, 8.14 and 74.07 kDa were overexpressed in the non-responder group, whereas one at 28 kDa was increased in the responder population (sensitivity>56%, specificity>77.5%). Moreover, combination of several biomarkers improved the sensitivity and specificity of the detection of patient response to over 97%. The 28 kDa protein was characterised as apolipoprotein A-I and the 7.77 kDa biomarker was identified as platelet factor 4. Conclusions: Six plasma biomarkers are characterised, enabling the detection of patient response to infliximab with high sensitivity and specificity. Apolipoprotein A-1 was predictive of a good response to infliximab, whereas platelet factor 4 was associated with non-responders.

Rheumatoid Arthritis and Fibromyalgia: A Frequent Unrelated Association Complicating Disease Management

Objective To assess the value of the 28-joint Disease Activity Score (DAS28) in evaluating disease activity in rheumatoid arthritis (RA) associated with fibromyalgia (FM). In this situation, because of the weight of the subjective measures included in the DAS28 equation, the patient’s status may be overestimated, leading to inappropriate treatment. We analyze the relationship between RA and FM and discuss whether the association is random or a marker of poor prognosis. Methods A questionnaire, developed when biologic therapies were introduced, was administered and the results analyzed in a consecutive, female outpatient population including 105 patients with RA, 49 with RA and FM (RAF), and 28 with FM. Psychosocial characteristics, disease presentation, and radiographic joint destruction evaluation were compared in the 3 populations. Results The presentation of RA was the same in patients with RA and RAF, but the 2 populations differed by socioprofessional characteristics, significantly higher disease activity in patients with RAF, and significantly more severe joint destruction in patients with RA. The RAF group was similar to the FM control population in socioprofessional and some physical characteristics. Regression analysis using the DAS28 measures differed significantly in the weight allowed to 28-joint counts for pain and swelling, but the constant factor was higher in patients with RAF. Conclusion DAS28 overestimated objective RA severity in patients who also had FM. The association between RA and FM does not appear to be a marker of worse prognosis, but rather a fortuitous association between the 2 diseases and one that may afford these patients some protection against joint destruction.

Fcγ receptor type IIIA polymorphism influences treatment outcomes in patients with rheumatoid arthritis treated with rituximab

Objective To assess the association between a single nucleotide polymorphism in the gene of FCGR3A and the response to treatment with rituximab (RTX) in rheumatoid arthritis (RA). Methods SMART is a randomised open trial assessing two strategies of re-treatment in patients responding to 1 g infusion of RTX with methotrexate on days 1 and 15 after failure, intolerance or contraindication to tumour necrosis factor (TNF) blockers. Among the 224 patients included, 111 could be genotyped and were included in an ancillary study of SMART. Univariate and multivariate analyses adjusted on disease activity score on 28 joints were performed to assess whether FCGR3A-158V/F polymorphism was associated with European League Against Rheumatism response at week 24. Results Among the 111 patients, 90 (81%) were responders of whom 30 (27%) were good responders. V allele carriage was significantly associated with a higher response rate (91% of responders vs 70%, OR 4.6 (95% CI 1.5 to 13.6), p=0.006). These results were also confirmed in rheumatoid factor-positive patients (93% vs 74%, p=0.025). In multivariate analysis, V allele carriage was independently associated with response to RTX (OR 3.8 (95% CI 1.2 to 11.7), p=0.023). Conclusion The 158V/F polymorphism of FCGR3A seems to influence the response to RTX in patients with RA after failure, intolerance or contraindication to TNF blockers.

Murine dendritic cell transdifferentiation into osteoclasts is differentially regulated by innate and adaptive cytokines

Dendritic cells (DC) are the mononuclear cells that initiate adaptive immune responses. Osteoclasts (OC) are the multinucleated giant cells that resorb bone. As previously described for human conventional DC (cDC), we demonstrate that murine cDC, either in vitro generated from Fms‐like tyrosine kinase 3 (Flt3)+ bone marrow progenitors or ex vivo purified from spleen, are able to develop into OC in response to M‐CSF and receptor activator of NF‐κB ligand (RANKL) in vitro. This transdifferentiation is driven by the immune environment that controls cDC maturation, cell fusion, tartrate‐resistant acid phosphatase (TRAP) and bone resorption activities. Only immature cDC have the capacity to become OC since mature cDC or plasmacytoid DC do not. Additions of the pro‐inflammatory cytokines, such as IL‐1β and TNF‐α, or human rheumatoid synovial fluid, increase murine cDC transdifferentiation into OC, whereas IFN‐α inhibits it. The adaptive cytokine, IFN‐γ, inhibits cDC fusion while IL‐4 increases it. IL‐2, IFN‐γ and IL‐4 inhibit TRAP and bone resorption activities contrary to IL‐10, which enhances both activities. A putative new “immune multinucleated giant cell” unable to resorb bone, which is formed owing to IL‐4, is underlined. The future analysis of cDC transdifferentiation into OC in murine models of inflammatory arthritis will give us the quantitative importance of this phenomenon in vivo.