Impact of immunogenicity on efficacy and tolerability of tumour necrosis factor inhibitors: pooled analysis of biosimilar studies in rheumatoid arthritis.

Objective: SB4, SB2, and SB5 are biosimilars of etanercept (ETN), infliximab (INF), and adalimumab (ADA), respectively. This pooled analysis evaluated the immunogenicity of these treatments across three phase III randomized controlled trials of patients with rheumatoid arthritis (RA). Methods: Patients had to have at least one anti-drug antibody (ADAb) assessment up to the time of the primary endpoint from each study (week 24 in SB4 and SB5 studies; week 30 in SB2 study). The effect of ADAbs on American College of Rheumatology 20% (ACR20) response and the incidences of injection-site reactions (ISRs)/infusion-related reactions (IRRs) were evaluated. Results: The study included 1709 patients. The cumulative incidences of ADAbs were 30.3% in the all-treatments-combined group, 29.1% in the biosimilars combined group, and 31.5% in the reference products combined group. ACR20 response rates were significantly lower in ADAb-positive patients in the all-treatments-combined [odds ratio (95% confidence interval) 1.77 (1.37, 2.27), p < 0.0001], biosimilars combined [2.24 (1.53, 3.30), p < 0.0001], and reference products combined [1.49 (1.06, 2.09), p = 0.0225] groups. ADAb-positive patients also had a higher likelihood of developing ISRs/IRRs in the all-treatments-combined group [0.56 (0.31, 1.01), p = 0.0550], predominantly due to the results observed with SB2 + INF combined rather than with SB4 + ETN or SB5 + ADA combined. Conclusion: In this pooled analysis, ADAbs were associated with reduced efficacy in patients with RA treated with biosimilars (SB4, SB2, and SB5) or their reference products (ETN, INF, and ADA). ADAbs were associated with an increased incidence of ISRs/IRRs in those treated with SB2 + INF. Clinical trial registration numbers: NCT01936181 (SB2 study), NCT01895309 (SB4 study), and NCT02167139 (SB5 study).

ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document on the safety of targeted and biological therapies: an infectious diseases perspective (Soluble immune effector molecules [II]: agents targeting interleukins, immunoglobulins and complement factors).

BACKGROUND: The present review is part of the ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document on the safety of targeted and biological therapies. AIMS: To review, from an Infectious Diseases perspective, the safety profile of agents targeting interleukins, immunoglobulins and complement factors and to suggest preventive recommendations. SOURCES: Computer-based MEDLINE searches with MeSH terms pertaining to each agent or therapeutic family. CONTENT: Patients receiving interleukin-1 (IL-1) -targeted (anakinra, canakinumab or rilonacept) or IL-5-targeted (mepolizumab) agents have a moderate risk of infection and no specific prevention strategies are recommended. The use of IL-6/IL-6 receptor-targeted agents (tocilizumab and siltuximab) is associated with a risk increase similar to that observed with anti-tumour necrosis factor-α agents. IL-12/23-targeted agents (ustekinumab) do not seem to pose a meaningful risk of infection, although screening for latent tuberculosis infection may be considered and antiviral prophylaxis should be given to hepatitis B surface antigen-positive patients. Therapy with IL-17-targeted agents (secukinumab, brodalumab and ixekizumab) may result in the development of mild-to-moderate mucocutaneous candidiasis. Pre-treatment screening for Strongyloides stercoralis and other geohelminths should be considered in patients who come from areas where these are endemic who are receiving IgE-targeted agents (omalizumab). C5-targeted agents (eculizumab) are associated with a markedly increased risk of infection due to encapsulated bacteria, particularly Neisseria spp. Meningococcal vaccination and chemoprophylaxis must be administered 2-4 weeks before initiating eculizumab. Patients with high-risk behaviours and their partners should also be screened for gonococcal infection. IMPLICATIONS: Preventive strategies are particularly encouraged to minimize the occurrence of neisserial infection associated with eculizumab.

Evaluation of newly proposed remission cut-points for disease activity score in 28 joints (DAS28) in rheumatoid arthritis patients upon IL-6 pathway inhibition.

BACKGROUND: Stringent remission criteria are crucial in rheumatoid arthritis (RA) assessment. Disease activity score in 28 joints (DAS28)-remission has not been included among American College of Rheumatology/European League Against Rheumatism definitions, because of its association with significant residual disease activity, partly due to high weighting of acute-phase reactants (APR). New, more stringent cut-points for DAS28-remission have recently been proposed that are suggested to reflect remission by clinical and simplified disease activity indices (clinical disease activity index (CDAI), simple disease activity index (SDAI)). However, their stringency in therapies directly influencing APR, like IL-6-blockers, has not been tested. We tested the new cut-points in patients with RA receiving tocilizumab. METHODS: We used data from randomised controlled trials of tocilizumab and evaluated patients in remission according to new DAS28-C-reactive protein (DAS-CRP) and DAS-erythrocyte sedimentation rate (DAS-ESR) cut-points (1.9 and 2.2). We assessed their disease activity state using the CDAI, SDAI and Boolean criteria and analysed their individual residual core set variables, like swollen joint counts (SJC28). RESULTS: About 50% of patients in DAS28-CRP-remission (<1.9) fell into higher disease activity states when assessed with CDAI, SDAI or Boolean criteria. Also, 15% had three or more (up to eight) SJC. Even higher disease activity was seen in patients classified as being in DAS28-ESR-remission (<2.2). CONCLUSIONS: Even with new, more stringent cut-points, DAS28-remission is frequently associated with considerable residual clinical disease activity, indicating that this limitation of the DAS28 is related to score construction rather than the choice of cut-points.

Disease activity states of the DAPSA, a psoriatic arthritis specific instrument, are valid against functional status and structural progression.

BACKGROUND: Recently, disease activity states were developed for the Disease Activity index for PSoriatic Arthritis (DAPSA). Here, we assess if different DAPSA disease activity states are associated with different degrees of functional impairment and different extents of joint damage progression in patients with psoriatic arthritis (PsA). METHODS: We used data from two pivotal trials of tumour necrosis factor (TNF) inhibitors in PsA (IMPACT II and GO-REVEAL) and identified patients in DAPSA remission (REM, ≤4), and low, moderate or high disease activity (LDA, ≤14; MDA, ≤28; HDA, >28) at 6 months. Across these groups we compared the functional scores (Health Assessment Questionnaire Disability Index, HAQ and physical component scale of the Short Form-36, PCS), and 1-year structural progression (PsA-modified Sharp/van der Heijde Score). RESULTS: We identified 310 from GO-REVEAL and 130 from IMPACT II, with a mean (SD) baseline DAPSA of 48.8 (26.4) and 44.6 (17.9), respectively. HAQ scores increased across patients groups in the four DAPSA disease activity states, while PCS decreased (p<0.001 for both). The mean progression in the combined cohort was -0.47 for REM, -0.28 for LDA, -0.14 for MDA and 0.51 for HDA (p<0.001). This association was also significant in the individual trial cohorts, and in the subgroups of patients treated with TNF inhibitors or placebo. Higher DAPSA scores were significantly and independently associated with probability of structural progression in multiple analyses. CONCLUSIONS: Disease activity states of the PsA specific DAPSA score are highly valid for future use as endpoints in clinical trials or as targets in clinical practice. TRIAL REGISTRATION NUMBERS: IMPACT 2: NCT02152254; GO-REVEAL: NCT00265096.

Clinical joint inactivity predicts structural stability in patients with established rheumatoid arthritis.

OBJECTIVES: Clinical joint activity is a strong predictor of joint damage in rheumatoid arthritis (RA), but progression of damage might increase despite clinical inactivity of the respective joint (silent progression). The aim of this study was to evaluate the prevalence of silent joint progression, but particularly on the patient level and to investigate the duration of clinical inactivity as a marker for non-progression on the joint level. METHODS: 279 patients with RA with any radiographic progression over an observational period of 3-5 years were included. We obtained radiographic and clinical data of 22 hand/finger joints over a period of at least 3 years. Prevalence of silent progression and associations of clinical joint activity and radiographic progression were evaluated. RESULTS: 120 (43.0%) of the patients showed radiographic progression in at least one of their joints without any signs of clinical activity in that respective joint. In only 7 (5.8%) patients, such silent joint progression would go undetected, as the remainder had other joints with clinical activity, either with (n=84; 70.0%) or without (n=29; 24.2%) accompanying radiographic progression. Also, the risk of silent progression decreases with duration of clinical activity. CONCLUSIONS: Silent progression of a joint without accompanying apparent clinical activity in any other joint of a patient was very rare, and would therefore be most likely detected by the assessment of the patient. Thus, full clinical remission is an excellent marker of structural stability in patients with RA, and the maintenance of this state reduces the risk of progression even further.

European League Against Rheumatism (EULAR) recommendations for the management of psoriatic arthritis with pharmacological therapies: 2015 update.

BACKGROUND: Since the publication of the European League Against Rheumatism recommendations for the pharmacological treatment of psoriatic arthritis (PsA) in 2012, new evidence and new therapeutic agents have emerged. The objective was to update these recommendations. METHODS: A systematic literature review was performed regarding pharmacological treatment in PsA. Subsequently, recommendations were formulated based on the evidence and the expert opinion of the 34 Task Force members. Levels of evidence and strengths of recommendations were allocated. RESULTS: The updated recommendations comprise 5 overarching principles and 10 recommendations, covering pharmacological therapies for PsA from non-steroidal anti-inflammatory drugs (NSAIDs), to conventional synthetic (csDMARD) and biological (bDMARD) disease-modifying antirheumatic drugs, whatever their mode of action, taking articular and extra-articular manifestations of PsA into account, but focusing on musculoskeletal involvement. The overarching principles address the need for shared decision-making and treatment objectives. The recommendations address csDMARDs as an initial therapy after failure of NSAIDs and local therapy for active disease, followed, if necessary, by a bDMARD or a targeted synthetic DMARD (tsDMARD). The first bDMARD would usually be a tumour necrosis factor (TNF) inhibitor. bDMARDs targeting interleukin (IL)12/23 (ustekinumab) or IL-17 pathways (secukinumab) may be used in patients for whom TNF inhibitors are inappropriate and a tsDMARD such as a phosphodiesterase 4-inhibitor (apremilast) if bDMARDs are inappropriate. If the first bDMARD strategy fails, any other bDMARD or tsDMARD may be used. CONCLUSIONS: These recommendations provide stakeholders with an updated consensus on the pharmacological treatment of PsA and strategies to reach optimal outcomes in PsA, based on a combination of evidence and expert opinion.

Persistence of subclinical sonographic joint activity in rheumatoid arthritis in sustained clinical remission.

BACKGROUND: Sonographic assessment, measuring grey scale (GS) and power Doppler (PD) signals, is a sensitive tool for the evaluation of inflammatory joint activity in patients with rheumatoid arthritis (RA). We evaluated the persistence of PD and GS signals in previously clinically active RA joints that have reached a state of continuous clinical inactivity. METHODS: We performed sonographic imaging of 22 joints of the hands of patients with RA, selected all joints without clinical activity but showing ongoing sonographic signs of inflammation, and evaluated the time from last clinical joint activity. RESULTS: A total of 90 patients with RA with 1980 assessed joints were included in this study. When comparing the mean time from clinical swelling, we found a significantly longer period of clinical inactivity in joints showing low sonographic activity (mean±SD time from swelling of 4.1±3.2 vs 3.1±2.9 years for PD1 vs PD≥2, p=0.031 and 4.5±3.4 vs 3.3±3.2 years for GS1 vs GS≥2, p≤0.0001). CONCLUSIONS: We conclude that subclinical joint activity is long-lasting in RA joints in clinical remission, but attenuates over time. The latter conclusion is based on the observed shorter time duration from last clinical activity for strong compared with weaker sonographic signals.

Personal factors in systemic sclerosis and their coverage by patient-reported outcome measures. A multicentre European qualitative study and literature review.

BACKGROUND: Systemic sclerosis (SSc) is an autoimmune disease where thickening of the skin can lead to reduced body function and limitations in activities. Severe forms can also affect and seriously damage inner organs. Patient-centred rehabilitation emphasises considerations of patients' background, experience and behavior which highlights the need to know if patient-reported outcome measures (PROMs) include such personal factors. AIM: To identify and describe personal factors in the experiences of functioning and health of persons with SSc and to examine if and to what extent PROMs in SSc research cover these factors. DESIGN: Data from a qualitative study with focus group interviews were analysed. PROMs in SSc research were identified in a literature review between 2008-2013. SETTING: Participants were recruited from outpatient clinics at rheumatology department. POPULATION: Sixty-three patients with SSc from four European countries participated. METHODS: Data from interviews were analysed using a structure of personal factors developed by Geyh et al. Identified PROMs were analysed and linked to main concepts, related to the personal factors, found in the interview data. RESULTS: Nineteen main concepts were related to the area "patterns of experience and behaviour" in the personal factor structure, 16 to "thoughts and beliefs", nine to "feelings", one to "motives" and one to "personal history and biography", respectively. Among the 35 PROMs identified, 15 did not cover any of the identified concepts. Concepts within the area "feelings" were mostly covered by the PROMs. Five of the PROMs covered "patterns of experience and behaviour", while "motives" and "personal history and biography" were not covered at all. Four of the identified PROMs covered concepts within the areas "feelings", "thoughts and beliefs" and "patterns of experience and behaviour" in the same instrument. The Illness Cognition Questionnaire and Illness Behaviour Questionnaire were such PROMs. CONCLUSION: Patterns of experience and behaviour had the highest number of concepts related to personal factors, but few of the PROMs in SSc research covered these factors. Only a few PROMs covered several personal factors areas in the same instrument. CLINICAL REHABILITATION IMPACT: The results would be of value when developing core sets for outcome measurements in SSc.

Certolizumab pegol in rheumatoid arthritis patients with low to moderate activity: the CERTAIN double-blind, randomised, placebo-controlled trial.

OBJECTIVES: This 52-week, randomised, double-blind phase IIIb study assessed efficacy and safety of certolizumab pegol (CZP) as add-on therapy to non-biologic disease-modifying antirheumatic drugs (DMARDs) in rheumatoid arthritis (RA) patients with low to moderate disease activity, and stopping therapy in patients in sustained remission. METHODS: Patients were randomised 1:1 to CZP (400 mg at weeks 0, 2 and 4, then 200 mg every 2 weeks) or placebo (every 2 weeks) plus current non-biologic DMARDs. At week 24, patients who achieved the primary endpoint of Clinical Disease Activity Index (CDAI) remission at both weeks 20 and 24 stopped study treatment and continued in the study until week 52. RESULTS: Of 194 patients (CZP=96; placebo=98), >90% had moderate disease activity at baseline. Significantly more CZP patients met the primary endpoint than placebo patients (week 20 and 24 CDAI remission rates: 18.8% vs 6.1%; p≤0.05). At week 24, 63.0% vs 29.7% of CZP versus placebo patients (p<0.001) achieved LDA. Disease activity score (ESR) based on 28-joint count and Simplified Disease Activity Index remission rates were also significantly higher with CZP versus placebo (19.8% vs 3.1%; p≤0.01 and 14.6% vs 4.1%; p≤0.05). CZP patients reported improvements in physical function versus placebo (mean Health Assessment Questionnaire-Disability-Index change from baseline: CZP, -0.25 vs placebo, -0.03; p≤0.01). During the period following withdrawal of CZP or placebo, only 3/17 prior CZP patients and 2/6 prior placebo patients maintained CDAI remission until week 52, but CZP reinstitution allowed renewed improvement. Adverse and serious adverse event rates were comparable between CZP and placebo groups. CONCLUSIONS: Addition of CZP to non-biologic DMARDs is an effective treatment in RA patients with predominantly moderate disease activity, allowing low-disease activity or remission to be reached in a majority of the patients. However, the data suggest that CZP cannot be withdrawn in patients achieving remission. TRIAL REGISTRATION NUMBER: NCT00674362.

Relationship between radiographic joint space narrowing, sonographic cartilage thickness and anatomy in rheumatoid arthritis and control joints.

OBJECTIVE: To validate ultrasound (US) for measuring metacarpal cartilage thickness (MCT), by comparing it with anatomical measurement using cadaver specimens. To correlate US MCT with radiographic joint space narrowing (JSN) or width (JSW) in patients with rheumatoid arthritis (RA). METHODS: Bilateral metacarpophalangeal (MCP) joints of 35 consecutive outpatients, with recent hand X-rays, were included in the analysis. Metacarpal and phalangeal cartilage of MCP 2-5 was assessed bilaterally by US. JSW and JSN were evaluated on X-rays by the van der Heijde modified Sharp method (vdHS). In addition, cadaver specimens of MCP 2-5 joints (n=19) were evaluated by anatomical measurement and US. RESULTS: The agreement (intraclass correlation coefficient) between sonographic and anatomical MCT on cadaver specimens of MCP joints was 0.61. MCT of individual MCP joints correlated with individual MCP JSN (r=-0.32, p<0.001) and individual MCP JSW (r=0.72, p<0.001). No correlation was found between phalangeal cartilage thickness and JSN in individual MCP joints. The US MCT summary score for MCP joints 2-5 correlated with summary scores for JSW (r=0.78, p<0.001), JSN (r=-0.5, p<0.001), erosion score of the vdHS (r=-0.39, p<0.001) and total vdHS (r=-0.47, p<0.001). CONCLUSIONS: Sonographic cartilage assessment in MCPs is closely related to anatomical cartilage thickness. Both JSW and JSN by radiography represent cartilage thickness in the MCP joints of patients with RA quite well. Thus, US is a valid tool for measuring MCT if radiographs are not available or in case of joint malalignment.

Scores for all seasons: SDAI and CDAI.

Disease activity assessment is one of the most pivotal aspects in the care of RA patients. Composite measures of disease activity are superior to individual measures, since they capture the multiple facets of the disease. Since swollen joint counts correlate with joint damage progression and tender joint counts with physical function, composite scores that include joint counts are preferable. The simplified and clinical disease activity indices (SDAI, CDAI) are easy to calculate and correlate well with joint damage and physical function. Cutpoints for disease activity states have been established and improvement criteria likewise. The SDAI and CDAI remission criteria (ACR-EULAR index-based remission) are stringent, usually associated with a halt of progression of damage and optimisation of physical function and can still be achieved in 1 of 4 clinic patients and up to one third of patients in trials of early arthritis.

The early clinical course of infliximab treatment in rheumatoid arthritis: results from the REMARK observational study.

OBJECTIVES: We aimed to describe patterns of disease activity during infliximab plus methotrexate (MTX) treatment and explore C-reactive protein (CRP) as a potential marker of early response. METHODS: REMARK was a phase IV, open-label, observational study of infliximab-naïve adults with rheumatoid arthritis (RA) who received infliximab 3 mg/kg plus MTX for 14 weeks. Treatment response was evaluated in 3 subgroups: patients with <1 year disease duration who were TNF-inhibitor (TNFi)-naïve, patients with ≥ 1 year disease duration who were TNFi-naïve, and patients who had previous TNFi failure or intolerance. In post hoc analyses, CRP kinetic profiles were analysed by EULAR response (good, moderate, non-response) in REMARK and in an independent replication with data from the ASPIRE study. RESULTS: In the efficacy-evaluable population (n=662), median 28-joint disease activity score (DAS28) improved from baseline to Week 14 (5.2 vs. 3.6, p<0.0001). Regardless of disease history subgroup, most patients had good or moderate EULAR responses at Weeks 2 (64.9%), 6 (74.1%), and 14 (73.6%). DAS28 and its components did not differ across patient subgroups. Disease flare occurred in 16.2% of patients. CRP levels declined markedly at Week 2, but patients who were EULAR non-responders at Week 14 showed a CRP rebound at Weeks 6 and 14. This CRP pattern was independently replicated in data from ASPIRE. Adverse events were consistent with the known risk profile of infliximab. CONCLUSIONS: Infliximab plus MTX treatment in patients with RA rapidly diminished disease activity. A unique pattern of CRP rebound was found in non-responders early in treatment.

Associations of nailfold capillary abnormalities and immunological markers in early Raynaud's phenomenon.

OBJECTIVES: Nailfold capillaroscopy (NC) and laboratory tests for antinuclear antibodies (ANA) are routinely used in parallel for detection of emerging connective tissue disease (CTD) in patients with Raynaud's phenomenon (RP). The aim of this study was to assess the associations between distinct nailfold capillary abnormalities and concomitant autoantibodies in patients with incipient RP without previously known CTD. METHOD: Patients with incipient RP without previously known CTD were included in this retrospective analysis. We analysed the association of particular capillary abnormalities (reduced density, avascular fields, dilations, giant capillaries, haemorrhages, tortuosity, ramifications, oedema) with ANA and ANA subsets (anti-Scl-70, anti-CENP-B, anti-U1-RNP, anti-dsDNA, anti-SSA(Ro), anti-SSB(La), anti-Sm, and anti-Jo-1 antibodies). We also developed a score that allows the estimation of each patient's individual probability for the presence of an ANA titre ≥ 1:160. RESULTS: The final analysis comprised 2971 patients. Avascular fields, giant capillaries, reduced capillary density, and capillary oedema were closely related to an ANA titre ≥ 1:160. Both giant capillaries and avascular fields were associated with anti-Scl-70 and anti-CENP-B antibodies. Only a weak association was found between giant capillaries and anti-U1-RNP antibodies. Each patient's individual probability for the presence of an ANA titre ≥ 1:160 can be represented by a sum score comprising giant capillaries, reduced density, avascular fields, ramifications, and oedema as well as patients' sex and age. CONCLUSION: In patients with incipient RP, anti-Scl-70 and anti-CENP-B antibodies are related most specifically to distinct capillary alterations. Although a sum score can represent the patient's probability for elevated ANA titres, NC cannot substitute for immunological tests in patients with incipient RP.

Treating axial and peripheral spondyloarthritis, including psoriatic arthritis, to target: results of a systematic literature search to support an international treat-to-target recommendation in spondyloarthritis.

BACKGROUND: Current recommendations for the management of axial spondyloarthritis (SpA) and psoriatic arthritis are to monitor disease activity and adjust therapy accordingly. However, treatment targets and timeframes of change have not been defined. An international expert panel has been convened to develop 'treat-to-target' recommendations, based on published evidence and expert opinion. OBJECTIVE: To review evidence on targeted treatment for axial and peripheral SpA, as well as for psoriatic skin disease. METHODS: We performed a systematic literature search covering Medline, Embase and Cochrane, conference abstracts and studies in http://www.clinicaltrials.gov. RESULTS: Randomised comparisons of targeted versus routine treatment are lacking. Some studies implemented treatment targets before escalating therapy: in ankylosing spondylitis, most trials used a decrease in Bath Ankylosing Spondylitis Disease Activity Index; in psoriatic arthritis, protocols primarily considered a reduction in swollen and tender joints; in psoriasis, the Modified Psoriasis Severity Score and the Psoriasis Area and Severity Index were used. Complementary evidence correlating these factors with function and radiographic damage at follow-up is sparse and equivocal. CONCLUSIONS: There is a need for randomised trials that investigate the value of treat-to-target recommendations in SpA and psoriasis. Several trials have used thresholds of disease activity measures to guide treatment decisions. However, evidence on the effect of these data on long-term outcome is scarce. The search data informed the expert committee regarding the formulation of recommendations and a research agenda.

Pristane-induced lupus as a model of human lupus arthritis: evolvement of autoantibodies, internal organ and joint inflammation.

OBJECTIVE: Arthritis is frequently seen in human lupus, but rarely in lupus models. Pristane-induced lupus (PIL) can be induced in various mouse strains such as BALB/c and C57BL/6. We herein characterize clinical and histological features of arthritis in the context of systemic lupus and provide a prudent comparison with models of rheumatoid arthritis (RA). METHODS: A total of 57 BALB/c mice received pristane (PIL group) and were analyzed for serum autoantibodies (anti-chromatin-, -histone, -Sm, -dsDNA), as well as for clinical features and histopathology of joints, lungs and kidneys. Joint pathology was quantified by image analysis and tissue cytometry. Ten C57BL/6 mice (Bl/6-PIL) and historical groups of two different RA models were analyzed accordingly. RESULTS: In BALB/c PIL, clinical arthritis started at three months, occurred finally in 79% of PIL (but not in controls, p<0.001) and correlated with areas of inflammation, erosion, cartilage damage, osteoclast numbers and total severity score (for all: r>0.7, p<0.001). After eight months, 58% of PIL (but no controls, p<0.001) had mild-erosive arthritis. In contrast to RA, the most frequent inflammatory cell type of the pannus was granulocytes (17.7%), PIL had lower numbers of osteoclasts, erosions rarely affected both layers of the cortical bone and there was no progression to complete joint destruction (even after one year of observation). Serum autoantibodies (auto-abs) preceded arthritis and became significantly elevated in all PIL; affected joints showed increased deposits of IgG (and IgM) within the inflammatory tissue, indicative of an ab-mediated process. PIL mice with arthritis also showed signs of pulmonary (100%) and renal (46%) lupus. In contrast to BALB/c, Bl/6-PIL mice did not develop any signs of arthritis. CONCLUSION: PIL in BALB/c mice is characterized by severe organ involvement, typical autoabs and by a mild-erosive arthritis with similarities to, but also with distinct differences from, RA. PIL may help to study arthritis along with other key features of systemic lupus erythematosus after therapeutic interventions or in knock-out models based on a BALB/c but not on a C57BL/6 background.

Abatacept (CTLA-4IG) treatment reduces the migratory capacity of monocytes in patients with rheumatoid arthritis.

OBJECTIVE: The binding of abatacept (CTLA-4Ig) to the B7 ligands CD80 and CD86 prevents the engagement of CD28 on T cells and thereby prevents effector T cell activation. In addition, a direct effect of CTLA-4Ig on antigen-presenting cells (APCs) could contribute to the therapeutic effect. To further elucidate the mechanism of CTLA-4Ig, we performed phenotype and functional analyses of APCs in patients with rheumatoid arthritis (RA) before and after the initiation of CTLA-4Ig therapy. METHODS: Peripheral blood mononuclear cells were analyzed before and at 2 and 4 weeks after the initiation of CTLA-4Ig therapy. Proportions of APCs were determined by flow cytometry. CD14+ monocytes were further analyzed for the expression of costimulatory and adhesion molecules and for their transendothelial migratory capacity in vitro. In addition, CD14+ monocytes from healthy controls were analyzed for their migratory and spreading capacity. RESULTS: Proportions and absolute numbers of monocytes were significantly increased in RA patients treated with CTLA-4Ig. The expression of several adhesion molecules was significantly diminished. In addition, monocytes displayed a significant reduction in their endothelial adhesion and transendothelial migratory capacity upon treatment with CTLA-4Ig. Likewise, isolated monocytes from healthy controls revealed a significant reduction in their migratory and spreading activity after preincubation with CTLA-4Ig or anti-CD80 and anti-CD86 antibodies. CONCLUSION: We describe direct effects of CTLA-4Ig therapy on phenotype and functional characteristics of monocytes in RA patients that might interfere with the migration of monocytes to the synovial tissue. This additional mechanism of CTLA-4Ig might contribute to the beneficial effects of CTLA-4Ig treatment in RA patients.