Deconstruction of rheumatoid arthritis synovium defines inflammatory subtypes.

Rheumatoid arthritis is a prototypical autoimmune disease that causes joint inflammation and destruction1. There is currently no cure for rheumatoid arthritis, and the effectiveness of treatments varies across patients, suggesting an undefined pathogenic diversity1,2. Here, to deconstruct the cell states and pathways that characterize this pathogenic heterogeneity, we profiled the full spectrum of cells in inflamed synovium from patients with rheumatoid arthritis. We used multi-modal single-cell RNA-sequencing and surface protein data coupled with histology of synovial tissue from 79 donors to build single-cell atlas of rheumatoid arthritis synovial tissue that includes more than 314,000 cells. We stratified tissues into six groups, referred to as cell-type abundance phenotypes (CTAPs), each characterized by selectively enriched cell states. These CTAPs demonstrate the diversity of synovial inflammation in rheumatoid arthritis, ranging from samples enriched for T and B cells to those largely lacking lymphocytes. Disease-relevant cell states, cytokines, risk genes, histology and serology metrics are associated with particular CTAPs. CTAPs are dynamic and can predict treatment response, highlighting the clinical utility of classifying rheumatoid arthritis synovial phenotypes. This comprehensive atlas and molecular, tissue-based stratification of rheumatoid arthritis synovial tissue reveal new insights into rheumatoid arthritis pathology and heterogeneity that could inform novel targeted treatments.

Analysis of Complement Gene Expression, Clinical Associations, and Biodistribution of Complement Proteins in the Synovium of Early Rheumatoid Arthritis Patients Reveals Unique Pathophysiologic Features.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial hyperplasia and inflammation. The finding of autoantibodies in seropositive RA suggests that complement system activation might play a pathophysiologic role due to the local presence of immune complexes in the joints. Our first objective was to explore the Pathobiology of Early Arthritis Cohort (PEAC) mRNA sequencing data for correlations between clinical disease severity as measured by DAS28-ESR (disease activity score in 28 joints for erythrocyte sedimentation rate) and complement system gene expression, both in the synovium and in blood. Our second objective was to determine the biodistribution using multiplex immunohistochemical staining of specific complement activation proteins and inhibitors from subjects in the Accelerating Medicines Partnership (AMP) RA/SLE study. In the PEAC study, there were significant positive correlations between specific complement gene mRNA expression levels in the synovium and DAS28-ESR for the following complement genes: C2, FCN1, FCN3, CFB, CFP, C3AR1, C5AR1, and CR1 Additionally, there were significant negative correlations between DAS28-ESR and Colec12, C5, C6, MASP-1, CFH, and MCP In the synovium there were also significant positive correlations between DAS28-ESR and FcγR1A, FcγR1B, FcγR2A, and FcγR3A Notably, CFHR4 synovial expression was positively correlated following treatment with the DAS28-ESR at 6 mo, suggesting a role in worse therapeutic responses. The inverse correlation of C5 RNA expression in the synovium may underlie the failure of significant benefit from C5/C5aR inhibitors in clinical trials performed in patients with RA. Multiplex immunohistochemical analyses of early RA synovium reveal significant evidence of regional alterations of activation and inhibitory factors that likely promote local complement activation.

Mitochondrial-mediated inflammation and platelet activation in giant cell arteritis.

Markers of extracellular mitochondria are present in giant cell arteritis (GCA) patients. However, their role in promoting inflammation and platelet activation is no known. To investigate this, isolated mitochondria were opsonized with plasma from GCA patients or healthy individuals and incubated with peripheral blood mononuclear cells (PBMCs) or platelets and assessed for inflammatory cytokine production and platelet activation. Plasma from GCA patients promoted increased mitochondrial-mediated cytokine production by PBMCs as compared to healthy controls (p < 0.05). Mitochondria opsonized with plasma factors from patients with GCA induced higher platelet activation as compared to mitochondria opsonized with plasma factors from healthy individuals (p = 0.0015). Platelet levels of P-selectin were associated with disease activity in GCA (r = 0.34, p = 0.01). GCA patients have impaired ability to regulate the clearance of extracellular mitochondria, possibly contributing to excessive inflammation and platelet activation. Targeting key drivers of mitochondrial extrusion and/or their clearance could lead to new therapeutic interventions in GCA.

Neutrophil extracellular trap formation in anti-neutrophil cytoplasmic antibody-associated and large-vessel vasculitis.

Levels of neutrophil extracellular traps (NETs) were measured in plasma of healthy controls (HC, n = 30) and patients with granulomatosis with polyangiitis (GPA, n = 123), microscopic polyangiitis (MPA, n = 61), Takayasu's arteritis (TAK, n = 58), and giant cell arteritis (GCA, n = 68), at times of remission or activity and correlated with levels of the platelet-derived thrombospondin-1 (TSP-1). Levels of NETs were elevated during active disease in patients with GPA (p < 0.0001), MPA (p = 0.0038), TAK (p < 0.0001), and GCA (p < 0.0001), and in remission for GPA, p < 0.0001, MPA, p = 0.005, TAK, p = 0.03, and GCA, p = 0.0009. All cohorts demonstrated impaired NET degradation. Patients with GPA (p = 0.0045) and MPA (p = 0.005) had anti-NET IgG antibodies. Patients with TAK had anti-histone antibodies (p < 0.01), correlating with presence of NETs. Levels of TSP-1 were increased in all patients with vasculitis, and associated with NET formation. NET formation is a common process in vasculitides. Targeting NET formation or degradation could be potential therapeutic approaches for vasculitides.

Rituximab versus azathioprine for maintenance of remission for patients with ANCA-associated vasculitis and relapsing disease: an international randomised controlled trial.

OBJECTIVE: Following induction of remission with rituximab in anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) relapse rates are high, especially in patients with history of relapse. Relapses are associated with increased exposure to immunosuppressive medications, the accrual of damage and increased morbidity and mortality. The RITAZAREM trial compared the efficacy of repeat-dose rituximab to daily oral azathioprine for prevention of relapse in patients with relapsing AAV in whom remission was reinduced with rituximab. METHODS: RITAZAREM was an international randomised controlled, open-label, superiority trial that recruited 188 patients at the time of an AAV relapse from 29 centres in seven countries between April 2013 and November 2016. All patients received rituximab and glucocorticoids to reinduce remission. Patients achieving remission by 4 months were randomised to receive rituximab intravenously (1000 mg every 4 months, through month 20) (85 patients) or azathioprine (2 mg/kg/day, tapered after month 24) (85 patients) and followed for a minimum of 36 months. The primary outcome was time to disease relapse (either major or minor relapse). RESULTS: Rituximab was superior to azathioprine in preventing relapse: HR 0.41; 95% CI 0.27 to 0.61, p<0.001. 19/85 (22%) patients in the rituximab group and 31/85 (36%) in the azathioprine group experienced at least one serious adverse event during the treatment period. There were no differences in rates of hypogammaglobulinaemia or infection between groups. CONCLUSIONS: Following induction of remission with rituximab, fixed-interval, repeat-dose rituximab was superior to azathioprine for preventing disease relapse in patients with AAV with a prior history of relapse. TRIAL REGISTRATION NUMBER: NCT01697267; ClinicalTrials.gov identifier.

Ocular manifestations of ANCA-associated vasculitis.

OBJECTIVES: ANCA-associated vasculitis (AAV) is a group of multisystem diseases that can have several ocular manifestations. There are published data on ocular manifestations of granulomatosis with polyangiitis (GPA), but few for eosinophilic granulomatosis with polyangiitis (EGPA) or microscopic polyangiitis (MPA). There is little information concerning chronicity, complications, and association with other cranial manifestations of AAV. METHODS: This study retrospectively analysed longitudinal multicentre cohorts of individuals with AAV followed between 2006 and 2022. Data included diagnosis, demographics, cranial manifestations of disease, presence of manifestations at onset of disease and/or follow-up, and ocular complications of disease. Univariate and multivariable logistic regression analysis assessed associations across disease manifestations. RESULTS: Data from 1441 patients were analysed, including 395 with EGPA, 876 with GPA, and 170 with MPA. Ocular manifestations were seen within 23.1% of patients: 39 (9.9%) with EGPA, 287 (32.7%) with GPA, and 12 (7.1%) with MPA at any time in the disease course. There were more ocular manifestations at onset (n = 224) than during follow-up (n = 120). The most common disease-related manifestations were conjunctivitis/episcleritis and scleritis. In multivariable analysis, dacryocystitis, lacrimal duct obstruction, and retro-orbital disease were associated with sinonasal manifestations of GPA; ocular manifestations were associated with hearing loss in MPA. The most common ocular complications and/or damage seen were cataracts (n = 168) and visual impairment (n = 195). CONCLUSION: Ocular manifestations occur in all forms of AAV, especially in GPA. Clinicians should be mindful of the wide spectrum of ocular disease in AAV, caused by active vasculitis, disease-associated damage, and toxicities of therapy.

2023 American College of Rheumatology and American Association of Hip and Knee Surgeons Clinical Practice Guideline for the Optimal Timing of Elective Hip or Knee Arthroplasty for Patients With Symptomatic Moderate-to-Severe Osteoarthritis or Advanced Symptomatic Osteonecrosis With Secondary Arthritis for Whom Nonoperative Therapy Is Ineffective.

OBJECTIVE: To develop evidence-based consensus recommendations for the optimal timing of hip and knee arthroplasty to improve patient-important outcomes including, but not limited to, pain, function, infection, hospitalization, and death at 1 year for patients with symptomatic and radiographic moderate-to-severe osteoarthritis or advanced symptomatic osteonecrosis with secondary arthritis of the hip or knee who have previously attempted nonoperative therapy, and for whom nonoperative therapy was ineffective, and who have chosen to undergo elective hip or knee arthroplasty (collectively referred to as TJA). METHODS: We developed 13 clinically relevant population, intervention, comparator, outcomes (PICO) questions. After a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to rate the quality of evidence (high, moderate, low, or very low), and evidence tables were created. A Voting Panel, including 13 physicians and patients, discussed the PICO questions until consensus was achieved on the direction (for/against) and strength (strong/conditional) of the recommendations. RESULTS: The panel conditionally recommended against delaying TJA to pursue additional nonoperative treatment including physical therapy, nonsteroidal antiinflammatory drugs, ambulatory aids, and intraarticular injections. It conditionally recommended delaying TJA for nicotine reduction or cessation. The panel conditionally recommended delay for better glycemic control for patients who have diabetes mellitus, although no specific measure or level was identified. There was consensus that obesity by itself was not a reason for delay, but that weight loss should be strongly encouraged, and the increase in operative risk should be discussed. The panel conditionally recommended against delay in patients who have severe deformity or bone loss, or in patients who have a neuropathic joint. Evidence for all recommendations was graded as low or very low quality. CONCLUSION: This guideline provides evidence-based recommendations regarding the optimal timing of TJA in patients who have symptomatic and radiographic moderate-to-severe osteoarthritis or advanced symptomatic osteonecrosis with secondary arthritis for whom nonoperative therapy was ineffective to improve patient-important outcomes, including pain, function, infection, hospitalization, and death at 1 year. We acknowledge that the evidence is of low quality primarily due to indirectness and hope future research will allow for further refinement of the recommendations.

Efficacy of leflunomide in the treatment of vasculitis.

OBJECTIVES: Only a few small case series, case reports, and one small clinical trial suggested some benefit of leflunomide (LEF) in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis and other vasculitides. We analysed the clinical efficacy and tolerability of LEF in a large cohort of patients with various vasculitides. METHODS: This was a retrospective analysis of patients who received LEF for treatment of their vasculitis enrolled in the Vasculitis Clinical Research Consortium (VCRC) Longitudinal Study and in 3 additional centres from the Canadian vasculitis research network (CanVasc). RESULTS: Data for 93 patients were analysed: 45 had granulomatosis with polyangiitis (GPA), 8 microscopic polyangiitis (MPA), 12 eosinophilic granulomatosis with polyangiitis (EGPA), 14 giant-cell arteritis (GCA), 9 Takayasu's arteritis (TAK), and 5 polyarteritis nodosa (PAN). The main reason for initiation of LEF was active disease (89%). LEF was efficacious for remission induction or maintenance at 6 months for 62 (67%) patients (64% with GCA, 89% with TAK, 80% with PAN, 69% with GPA, 75% with MPA, 33% with EGPA); 20% discontinued LEF before achieving remission because of persistent disease activity. Overall, 22 adverse events (gastrointestinal symptoms being the most common) led to drug discontinuation in 18 (19%) patients, of which 12 stopped LEF before month 6, before showing any benefit in 8/12 of these patients. CONCLUSIONS: Leflunomide can be an effective therapeutic option for various vasculitides, especially for non-severe refractory or relapsing ANCA-associated vasculitis or large-vessel vasculitis. No new safety signals for LEF were identified in this population.

B cells in rheumatoid arthritis synovial tissues encode focused antibody repertoires that include antibodies that stimulate macrophage TNF-α production.

Rheumatoid arthritis (RA) is characterized by the production of anti-citrullinated protein antibodies (ACPAs). To gain insights into the relationship between ACPA-expressing B cells in peripheral blood (PB) and synovial tissue (ST), we sequenced the B cell repertoire in paired PB and ST samples from five individuals with established, ACPA+ RA. Bioinformatics analysis of paired heavy- and light-chain sequences revealed clonally-related family members shared between PB and ST. ST-derived antibody repertoires exhibited reduced diversity and increased normalized clonal family size compared to PB-derived repertoires. Functional characterization showed that seven recombinant antibodies (rAbs) expressed from subject-derived sequences from both compartments bound citrullinated antigens and immune complexes (ICs) formed using one ST-derived rAb stimulated macrophage TNF-α production. Our findings demonstrate B cell trafficking between PB and ST in subjects with RA and ST repertoires include B cells that encode ACPA capable of forming ICs that stimulate cellular responses implicated in RA pathogenesis.

Adalimumab Immunogenicity Is Negatively Correlated with Anti-Hinge Antibody Levels in Patients with Rheumatoid Arthritis.

Patients with rheumatoid arthritis (RA) are frequently treated with anti-tumor necrosis factor-α immunoglobulin therapy but develop neutralizing antibodies against these drugs, necessitating therapeutic monitoring of drug concentrations and anti-drug antibodies. Patients with RA have multiple factors related to their autoimmune disposition that interfere with conventionally used methods to detect anti-drug antibodies. Currently deployed analytical methods have significant limitations that hinder clinical interpretation and/or routine use, and no method can detect immunogenicity and drug levels simultaneously to provide clinically meaningful recommendations. Given these limitations, the objective of this study was to identify sources of and associations with assay interference in patients with RA. We designed a modular immunogenicity and drug concentration detection technology to identify the factors that interfere with the detection of adalimumab and anti-adalimumab antibodies in a cohort of 206 patients with RA. Patients were included from the University of Pittsburgh Rheumatoid Arthritis Comparative Effectiveness Research registry. In this cohort, we analyzed clinical and plasma factors associated with anti-adalimumab and anti-hinge antibodies. A novel flow cytometry-based assay was developed and validated that simultaneously measures adalimumab and anti-adalimumab antibody concentrations, overcoming many of the interference factors that are limitations of conventional assays, including anti-fragment crystallizable (Fc) and anti-hinge antibodies. C-reactive protein (P = 0.035), Disease Activity Score-28 (DAS28) score (P = 0.002), and disease activity category (P = 0.009) were significantly associated with anti-adalimumab antibodies but not with anti-hinge antibodies (P > 0.05). Anti-hinge antibodies were inversely associated with drug-neutralizing antibodies (P = 0.002). In patients with RA, anti-hinge antibodies may have a potential protective effect against the development of anti-adalimumab antibodies. SIGNIFICANCE STATEMENT: Using a novel cytometric assay that simultaneously measures drug and anti-drug antibodies, we overcame many interferences that hinder the clinical interpretation of adalimumab immunogenicity testing. Our investigation in patients with RA demonstrated that immunogenicity impaired the pharmacological action of adalimumab via analysis of RA disease severity markers. We also demonstrate that patients with anti-hinge antibodies had lower anti-adalimumab antibody levels and decreased drug neutralization. Our results suggest that anti-hinge antibodies can predict adalimumab immunogenicity before the start of therapy.

Rituximab as therapy to induce remission after relapse in ANCA-associated vasculitis.

OBJECTIVES: Evaluation of rituximab and glucocorticoids as therapy to induce remission after relapse in ANCA-associated vasculitis (AAV) in a prospective observational cohort of patients enrolled into the induction phase of the RITAZAREM trial. METHODS: Patients relapsing with granulomatosis with polyangiitis or microscopic polyangiitis were prospectively enrolled and received remission-induction therapy with rituximab (4×375 mg/m2) and a higher or lower dose glucocorticoid regimen, depending on physician choice: reducing from either 1 mg/kg/day or 0.5 mg/kg/day to 10 mg/day by 4 months. Patients in this cohort achieving remission were subsequently randomised to receive one of two regimens to prevent relapse. RESULTS: 188 patients were studied: 95/188 (51%) men, median age 59 years (range 19-89), prior disease duration 5.0 years (range 0.4-34.5). 149/188 (79%) had previously received cyclophosphamide and 67/188 (36%) rituximab. 119/188 (63%) of relapses had at least one major disease activity item, and 54/188 (29%) received the higher dose glucocorticoid regimen. 171/188 (90%) patients achieved remission by 4 months. Only six patients (3.2% of the study population) did not achieve disease control at month 4. Four patients died in the induction phase due to pneumonia (2), cerebrovascular accident (1), and active vasculitis (1). 41 severe adverse events occurred in 27 patients, including 13 severe infections. CONCLUSIONS: This large prospective cohort of patients with relapsing AAV treated with rituximab in conjunction with glucocorticoids demonstrated a high level of efficacy for the reinduction of remission in patients with AAV who have relapsed, with a similar safety profile to previous studies.

Derivation of an angiographically based classification system in Takayasu's arteritis: an observational study from India and North America.

OBJECTIVES: To develop and replicate, using data-driven methods, a novel classification system in Takayasu's arteritis based on distribution of arterial lesions. METHODS: Patients were included from four international cohorts at major academic centres: India (Christian Medical College Vellore); North America (National Institutes of Health, Vasculitis Clinical Research Consortium and Cleveland Clinic Foundation). All patients underwent whole-body angiography of the aorta and branch vessels, with categorization of arterial damage (stenosis, occlusion or aneurysm) in 13 territories. K-means cluster analysis was performed to identify subgroups of patients based on pattern of angiographic involvement. Cluster groups were identified in the Indian cohort and independently replicated in the North American cohorts. RESULTS: A total of 806 patients with Takayasu's arteritis from India (n = 581) and North America (n = 225) were included. Three distinct clusters defined by arterial damage were identified in the Indian cohort and replicated in each of the North American cohorts. Patients in cluster one had significantly more disease in the abdominal aorta, renal and mesenteric arteries (P < 0.01). Patients in cluster two had significantly more bilateral disease in the carotid and subclavian arteries (P < 0.01). Compared with clusters one and two, patients in cluster three had asymmetric disease with fewer involved territories (P < 0.01). Demographics, clinical symptoms and clinical outcomes differed by cluster. CONCLUSION: This large study in Takayasu's arteritis identified and replicated three novel subsets of patients based on patterns of arterial damage. Angiographic-based disease classification requires validation by demonstrating potential aetiological or prognostic implications.

Inflammatory joint diseases and atherosclerosis: time to look beyond the 'lipid paradox'.

PURPOSE OF REVIEW: Uncertainty persists about the contribution of lipids to the increased risk of cardiovascular disease (CVD) among rheumatoid arthritis and other inflammatory joint disease (IJD) patients. In reviewing recent research, we consider potential insights gained by quantifying lipoprotein particles directly, rather than by their lipid content. RECENT FINDINGS: Although inflammation often decreases LDL cholesterol (LDL-C), and anti-inflammatory medications often increase LDL-C, both inflammation and anti-inflammatory medications can increase atherogenic Apolipoprotein B (ApoB)-containing lipoprotein particles, attenuated by statins. CVD risk factors, that is, smoking, obesity, ApoB, may increase years prior to IJD diagnosis. Increased risks of nonatherosclerotic myocardial and pulmonary disease, heart failure and mortality may be directly related to disease activity, inflammation, and possibly to HDL particles and function. SUMMARY: For IJD patients, higher cumulative lifetime exposure to CVD risk factors accelerates atherosclerosis and subsequent CVD risk that is underestimated by current risk factor levels. CVD risk reduction in IJD requires aggressive and earlier reduction in CVD risk factors (ApoB lipoproteins, smoking, hypertension, diabetes, lack of physical activity), in addition to control of disease activity and inflammation. Lipid-lowering medications can attenuate anti-inflammatory medication-induced increases in ApoB and LDL-C, but can also reduce CVD risk due to cumulative lifetime exposure.

Subglottic stenosis and endobronchial disease in granulomatosis with polyangiitis.

OBJECTIVES: To describe tracheobronchial disease in patients with granulomatosis with polyangiitis (GPA) and evaluate the utility of dynamic expiratory CT to detect large-airway disease. METHODS: Demographic and clinical features associated with the presence of subglottic stenosis (SGS) or endobronchial involvement were assessed in a multicentre, observational cohort of patients with GPA. A subset of patients with GPA from a single-centre cohort underwent dynamic chest CT to evaluate the airways. RESULTS: Among 962 patients with GPA, SGS and endobronchial disease were identified in 95 (10%) and 59 (6%) patients, respectively. Patients with SGS were more likely to be female (72% vs 53%, P < 0.01), younger at time of diagnosis (36 vs 49 years, P < 0.01), and have saddle-nose deformities (28% vs 10%, P < 0.01), but were less likely to have renal involvement (39% vs 62%, P < 0.01). Patients with endobronchial disease were more likely to be PR3-ANCA positive (85% vs 66%, P < 0.01), with more ENT involvement (97% vs 77%, P < 0.01) and less renal involvement (42% vs 62%, P < 0.01). Disease activity in patients with large-airway disease was commonly isolated to the subglottis/upper airway (57%) or bronchi (32%). Seven of 23 patients screened by dynamic chest CT had large-airway pathology, including four patients with chronic, unexplained cough, discovered to have tracheobronchomalacia. CONCLUSION: SGS and endobronchial disease occur in 10% and 6% of patients with GPA, respectively, and may occur without disease activity in other organs. Dynamic expiratory chest CT is a potential non-invasive screening test for large-airway involvement in GPA.

Serum cytokine and chemokine levels in patients with eosinophilic granulomatosis with polyangiitis, hypereosinophilic syndrome, or eosinophilic asthma.

OBJECTIVES: The pathogenesis of eosinophilic granulomatosis with polyangiitis (EGPA) remains poorly understood, and may overlap with eosinophilic asthma and primary hypereosinophilic syndrome (HES). The aim of this study was to analyse a panel of serum cytokines and chemokines as markers of disease activity in patients with these conditions. METHODS: The levels of 54 cytokines and chemokines were measured in the sera of 40 patients with active EGPA, 10 of these patients during inactive disease, 6 patients with HES, 8 with asthma, and 10 healthy controls. Serum cytokine/chemokines measured included interleukin (IL)-1α, 1ß, 3, 4, 5, 6, 8, 13, 15, 17A, 17E(25), 18, 23 and 33, soluble IL-2 receptor alpha, eotaxin-1 (CCL11), -2 (CCL24) and -3 (CCL26), macrophage-derived chemokine (MDC/CCL22), macrophage inflammatory protein (MIP)-1a and -1b, and tumour necrosis factor (TNF)-α. Results were compared between disease and control groups using regression analysis, with Bonferroni correction for multiple comparisons (significant p value ≤0.00093). RESULTS: Significant differences were observed only in serum levels of MDC, IL-8, MIP-1a and -1b, TNF-α, each of which were lower in patients with active EGPA than in healthy controls (p<0.0001). Differences between patients with active disease and other disease groups did not reach significance. Paired comparisons between sera from patients with active or inactive EGPA showed no significant difference for any of the studied cytokines or chemokines. CONCLUSIONS: No clear difference in the serum levels of measured cytokines and chemokines helped distinguish between active EGPA or inactive EGPA, or other disease or control groups.

14-3-3z sequesters cytosolic T-bet, upregulating IL-13 levels in TC2 and CD8+ lymphocytes from patients with scleroderma.

BACKGROUND: IL-13-producing CD8+ T cells have been implicated in the pathogenesis of type 2-driven inflammatory human conditions. We have shown that CD8+IL-13+ cells play a critical role in cutaneous fibrosis, the most characteristic feature of systemic sclerosis (SSc; scleroderma). However, the molecular mechanisms underlying production of IL-13 and other type 2 cytokines by CD8+ T cells remain unclear. OBJECTIVE: We sought to establish the molecular basis of IL-13 overproduction by CD8+ T cells from patients with SSc, focusing on T-bet modulation of GATA-3 activity, which we showed to underlie IL-13 overproduction in CD8+IL-13+ cells from patients with SSc. METHODS: Biochemical and biophysical methods were used to determine the expression and association of T-bet, GATA-3, and regulatory factors in CD8+ T cells isolated from the blood and lesional skin of patients with SSc with severe skin thickening. Chromatin immunoprecipitation analysis determined GATA-3 binding to the IL-13 promoter. ImageStream analysis and confocal microscopy visualized the subcellular localization of T-bet and GATA-3. Transcript levels were decreased by small interfering RNAs. RESULTS: Interaction of T-bet with the adaptor protein 14-3-3z in the cytosol of CD8+ T cells from patients with SSc reduces T-bet translocation into the nucleus and its ability to associate with GATA-3, allowing more GATA-3 to bind to the IL-13 promoter and inducing IL-13 upregulation. Strikingly, we show that this mechanism is also found during type 2 polarization of CD8+ T cells (TC2) from healthy donors. CONCLUSIONS: We identified a novel molecular mechanism underlying type 2 cytokine production by CD8+ T cells, revealing a more complete picture of the complex pathway leading to SSc disease pathogenesis.

Pain and Catastrophizing in Patients With Rheumatoid Arthritis: An Observational Cohort Study.

BACKGROUND: The aims of this study were to define changes in catastrophizing that occur with initiation of a new disease-modifying antirheumatic drug (DMARD) and to examine the relationship between changes in Clinical Disease Activity Index (CDAI) and changes in catastrophizing. METHODS: Participants in an ongoing multisite, observational study completed the Pain Catastrophizing Scale (PCS) before and 12 weeks after DMARD initiation. We used multivariable linear regression models to examine the association between changes in CDAI as the exposure and change in pain catastrophizing as the outcome. We also assessed the relationship between changes in each component of CDAI and change in PCS, using multivariable linear regression models. RESULTS: Among the 165 rheumatoid arthritis patients with data on CDAI at both time points, CDAI decreased from 22 to 11.5 on a 76-point scale (p < 0.0001) after 12 weeks. Pain intensity decreased from a median of 5 to 3 on a 10-point numeric rating scale (p < 0.0001), and catastrophizing decreased, from 16.0 to 12.0 on the 52-point PCS (p = 0.0005). Among the 163 with complete data for the regression analysis, changes in CDAI were positively correlated with changes in catastrophizing (standardized ß = 0.19, p = 0.01). Of the components of the CDAI, change in assessor global score was most strongly associated with changes in catastrophizing (standardized ß = 0.24, p = 0.003). CONCLUSIONS: Pain catastrophizing decreases, in conjunction with disease activity, after initiation of a new DMARD. These findings provide support for catastrophizing as a dynamic construct that can be altered with treatment directed at decreasing inflammatory disease activity and pain.

Human Leukocyte Antigen Shared Epitope and Inflammation, Cardiovascular Disease, Cancer, and Mortality Among Postmenopausal Women in the Women's Health Initiative Rheumatoid Arthritis Study.

Specific alleles of the human leukocyte antigen (HLA)-DRB1 gene (HLA-DRB1) encode a "shared epitope" (SE) associated with rheumatoid arthritis (RA), especially more severe cyclic-citrullinated peptide antibody-positive (anti-CCP+) RA. We evaluated associations of number of SE alleles (0, 1, or 2) with total and cardiovascular disease (CVD) mortality and incident coronary heart disease (CHD), CVD, and cancer over a mean 8.9 (standard deviation, 3.5) years of follow-up, stratifying by baseline anti-CCP status (positive (+) vs. negative (-)). A longitudinal study, the Women's Health Initiative RA Study (1993-2010), sampled postmenopausal women who reported RA at baseline (1993-1998) or follow-up in the Women's Health Initiative, classified as anti-CCP+ RA (n = 556) or anti-CCP- non-RA (n = 1,070). Among anti-CCP+ RA women, SE alleles were not related to age-adjusted risks of CHD, CVD, or cancer or to total or CVD mortality. Among anti-CCP- non-RA women, age-adjusted hazard ratios for 1 and 2 SE alleles versus 0 SE alleles were 0.41 (95% confidence interval (CI): 0.34, 0.50) and 0.44 (95% CI: 0.27, 0.72), respectively, for CVD; 0.43 (95% CI: 0.37, 0.53) and 0.30 (95% CI: 0.16, 0.64), respectively, for CHD; and 0.62 (95% CI: 0.53, 0.73) and 0.52 (95% CI: 0.33, 0.83), respectively, for cancer. Associations persisted after adjustment for CVD risk factors, joint pain, rheumatoid factor positivity, and inflammatory markers (white blood cell count or cytokine level). In future studies, investigators should evaluate SE associations among anti-CCP- adults without RA and potential mechanisms.

Increased pretreatment serum IFN-ß/α ratio predicts non-response to tumour necrosis factor α inhibition in rheumatoid arthritis.

OBJECTIVE: Studies suggest that circulating type I interferon (IFN) may predict response to biological agents in rheumatoid arthritis (RA). Prediction of response prior to initiating therapy would represent a major advancement. METHODS: We studied sera from a test set of 32 patients with RA from the Auto-immune Biomarkers Collaborative Network Consortium and a validation set of 92 patients with RA from the Treatment Efficacy and Toxicity in Rheumatoid Arthritis Database and Repository registry. The test set included those with good response or no response to tumour necrosis factor (TNF) inhibitors at 14 weeks by European League Against Rheumatism criteria. The validation set included subjects with good, moderate or no response at 12 weeks. Total serum type I IFN activity, IFN-α and IFN-ß activity were measured using a functional reporter cell assay. RESULTS: In the test set, an increased ratio of IFN-ß to IFN-α (IFN-ß/α activity ratio) in pretreatment serum associated with lack of response to TNF inhibition (p=0.013). Anti-cyclic citrullinated peptide antibody titre and class of TNF inhibitor did not influence this relationship. A receiver-operator curve supported a ratio of 1.3 as the optimal cut-off. In the validation set, subjects with an IFN-ß/α activity ratio >1.3 were significantly more likely to have non-response than good response (OR=6.67, p=0.018). The test had 77% specificity and 45% sensitivity for prediction of non-response compared with moderate or good response. Meta-analysis of test and validation sets confirmed strong predictive capacity of IFN-ß/α activity ratio (p=0.005). CONCLUSIONS: Increased pretreatment serum IFN-ß/α ratio strongly associated with non-response to TNF inhibition. This study supports further investigation of serum type I IFN in predicting outcome of TNF inhibition in RA.