IL11-mediated stromal cell activation may not be the master regulator of pro-fibrotic signaling downstream of TGFß.

Fibrotic diseases, such as idiopathic pulmonary fibrosis (IPF) and systemic scleroderma (SSc), are commonly associated with high morbidity and mortality, thereby representing a significant unmet medical need. Interleukin 11 (IL11)-mediated cell activation has been identified as a central mechanism for promoting fibrosis downstream of TGFß. IL11 signaling has recently been reported to promote fibroblast-to-myofibroblast transition, thus leading to various pro-fibrotic phenotypic changes. We confirmed increased mRNA expression of IL11 and IL11Rα in fibrotic diseases by OMICs approaches and in situ hybridization. However, the vital role of IL11 as a driver for fibrosis was not recapitulated. While induction of IL11 secretion was observed downstream of TGFß signaling in human lung fibroblasts and epithelial cells, the cellular responses induced by IL11 was quantitatively and qualitatively inferior to that of TGFß at the transcriptional and translational levels. IL11 blocking antibodies inhibited IL11Rα-proximal STAT3 activation but failed to block TGFß-induced profibrotic signals. In summary, our results challenge the concept of IL11 blockade as a strategy for providing transformative treatment for fibrosis.

The Clinical Response of Upadacitinib and Risankizumab Is Associated With Reduced Inflammatory Bowel Disease Anti-TNF-α Inadequate Response Mechanisms.

BACKGROUND: Janus kinase (JAK) 1 inhibitor upadacitinib and IL-23 inhibitor risankizumab are efficacious in inflammatory bowel disease (IBD) patients who are antitumor necrosis factor (anti-TNF)-α inadequate responders (TNF-IRs). We aimed to understand the mechanisms mediating the response of upadacitinib and risankizumab. METHODS: Eight tissue transcriptomic data sets from IBD patients treated with anti-TNF-α therapies along with single-cell RNAseq data from ulcerative colitis were integrated to identify TNF-IR mechanisms. The RNAseq colon tissue data from clinical studies of TNF-IR Crohn's disease patients treated with upadacitinib or risankizumab were used to identify TNF-IR mechanisms that were favorably modified by upadacitinib and risankizumab. RESULTS: We found 7 TNF-IR upregulated modules related to innate/adaptive immune responses, interferon signaling, and tissue remodeling and 6 TNF-IR upregulated cell types related to inflammatory fibroblasts, postcapillary venules, inflammatory monocytes, macrophages, dendritic cells, and cycling B cells. Upadacitinib was associated with a significant decrease in the expression of most TNF-IR upregulated modules in JAK1 responders (JAK1-R); in contrast, there was no change in these modules among TNF-IR patients treated with a placebo or among JAK1 inadequate responders (JAK1-IR). In addition, 4 of the 6 TNF-IR upregulated cell types were significantly decreased after upadacitinib treatment in JAK1-R but not among subjects treated with a placebo or among JAK1-IR patients. We observed similar findings from colon biopsy samples from TNF-IR patients treated with risankizumab. CONCLUSIONS: Collectively, these data suggest that upadacitinib and risankizumab affect TNF-IR upregulated mechanisms, which may account for their clinical response among TNF-IR IBD patients.

We identified molecular and cellular mechanisms associated with and potentially mediating the response of upadacitinib and risankizumab for IBD patients that inadequately responded to anti-TNF-α treatment.

Epithelial dysfunction is prevented by IL-22 treatment in a Citrobacter rodentium-induced colitis model that shares similarities with inflammatory bowel disease.

Inflammatory bowel disease (IBD) is characterized by a dysregulated intestinal epithelial barrier leading to breach of barrier immunity. Here we identified similar protein expression changes between IBD and Citrobacter rodentium-infected FVB mice with respect to dysregulation of solute transporters as well as components critical for intestinal barrier integrity. We attribute the disease associated changes in the model to the emergence of undifferentiated intermediate intestinal epithelial cells. Prophylactic treatment with IL-22.Fc in C. rodentium-infected FVB mice reduced disease severity and rescued the mice from lethality. Multi-omics and solute analyses revealed that IL-22.Fc treatment prevented disease-associated changes including disruption of the solute transporter machinery and restored proper physiological functions of the intestine, respectively. Taken together, we established the disease relevance of the C. rodentium-induced colitis model to IBD, demonstrated the protective role of IL-22 in amelioration of epithelial dysfunction and elucidated the molecular mechanisms with IL-22's effect on intestinal epithelial cells.

Synovial Inflammatory Pathways Characterize Anti-TNF-Responsive Rheumatoid Arthritis Patients.

OBJECTIVE: This study was undertaken to understand the mechanistic basis of response to anti-tumor necrosis factor (anti-TNF) therapies and to determine whether transcriptomic changes in the synovium are reflected in peripheral protein markers. METHODS: Synovial tissue from 46 rheumatoid arthritis (RA) patients was profiled with RNA sequencing before and 12 weeks after treatment with anti-TNF therapies. Pathway and gene signature analyses were performed on RNA expression profiles of synovial biopsies to identify mechanisms that could discriminate among patients with a good response, a moderate response, or no response, according to the American College of Rheumatology (ACR)/EULAR response criteria. Serum proteins encoded by synovial genes that were differentially expressed between ACR/EULAR response groups were measured in the same patients. RESULTS: Gene signatures predicted which patients would have good responses, and pathway analysis identified elevated immune pathways, including chemokine signaling, Th1/Th2 cell differentiation, and Toll-like receptor signaling, uniquely in good responders. These inflammatory pathways were correspondingly down-modulated by anti-TNF therapy only in good responders. Based on cell signature analysis, lymphocyte, myeloid, and fibroblast cell populations were elevated in good responders relative to nonresponders, consistent with the increased inflammatory pathways. Cell signatures that decreased following anti-TNF treatment were predominately associated with lymphocytes, and fewer were associated with myeloid and fibroblast populations. Following anti-TNF treatment, and only in good responders, several peripheral inflammatory proteins decreased in a manner that was consistent with corresponding synovial gene changes. CONCLUSION: Collectively, these data suggest that RA patients with robust responses to anti-TNF therapies are characterized at baseline by immune pathway activation, which decreases following anti-TNF treatment. Understanding mechanisms that define patient responsiveness to anti-TNF treatment may assist in development of predictive markers of patient response and earlier treatment options.

Lung gene expression and single cell analyses reveal two subsets of idiopathic pulmonary fibrosis (IPF) patients associated with different pathogenic mechanisms.

Idiopathic pulmonary fibrosis is a progressive and debilitating lung disease with large unmet medical need and few treatment options. We describe an analysis connecting single cell gene expression with bulk gene expression-based subsetting of patient cohorts to identify IPF patient subsets with different underlying pathogenesis and cellular changes. We reproduced earlier findings indicating the existence of two major subsets in IPF and showed that these subsets display different alterations in cellular composition of the lung. We developed classifiers based on the cellular changes in disease to distinguish subsets. Specifically, we showed that one subset of IPF patients had significant increases in gene signature scores for myeloid cells versus a second subset that had significantly increased gene signature scores for ciliated epithelial cells, suggesting a differential pathogenesis among IPF subsets. Ligand-receptor analyses suggested there was a monocyte-macrophage chemoattractant axis (including potentially CCL2-CCR2 and CCL17-CCR4) among the myeloid-enriched IPF subset and a ciliated epithelium-derived chemokine axis (e.g. CCL15) among the ciliated epithelium-enriched IPF subset. We also found that these IPF subsets had differential expression of pirfenidone-responsive genes suggesting that our findings may provide an approach to identify patients with differential responses to pirfenidone and other drugs. We believe this work is an important step towards targeted therapies and biomarkers of response.

Diminished cytokine-induced Jak/STAT signaling is associated with rheumatoid arthritis and disease activity.

Rheumatoid arthritis (RA) is a systemic and incurable autoimmune disease characterized by chronic inflammation in synovial lining of joints. To identify the signaling pathways involved in RA, its disease activity, and treatment response, we adapted a systems immunology approach to simultaneously quantify 42 signaling nodes in 21 immune cell subsets (e.g., IFNα→p-STAT5 in B cells) in peripheral blood mononuclear cells (PBMC) from 194 patients with longstanding RA (including 98 patients before and after treatment), and 41 healthy controls (HC). We found multiple differences between patients with RA compared to HC, predominantly in cytokine-induced Jak/STAT signaling in many immune cell subsets, suggesting pathways that may be associated with susceptibility to RA. We also found that high RA disease activity, compared to low disease activity, was associated with decreased (e.g., IFNα→p-STAT5, IL-10→p-STAT1) or increased (e.g., IL-6→STAT3) response to stimuli in multiple cell subsets. Finally, we compared signaling in patients with established, refractory RA before and six months after initiation of methotrexate (MTX) or TNF inhibitors (TNFi). We noted significant changes from pre-treatment to post-treatment in IFNα→p-STAT5 signaling and IL-10→p-STAT1 signaling in multiple cell subsets; these changes brought the aberrant RA signaling profiles toward those of HC. This large, comprehensive functional signaling pathway study provides novel insights into the pathogenesis of RA and shows the potential of quantification of cytokine-induced signaling as a biomarker of disease activity or treatment response.

Editing the immune system in vivo in mice using CRISPR/Cas9 ribonucleoprotein (RNP)-mediated gene editing of transplanted hematopoietic stem cells.

CRISPR/Cas9-based genome editing has been widely used to evaluate target gene function in biomedical research. The CRISPR/Cas9 system can introduce gene knockout, knock-in and mutations with more ease than earlier generations of genome editing tools. Using CRISPR/Cas9-based genome editing, researchers have successfully modified the DNA of different immune components, including primary T cells, B cells, macrophages, and immune system progenitors, i.e. hematopoietic stem cells (HSCs), which are also known as Lin-Sca1 + Kit + cells (LSKs) in mice. We previously reported that the transplantation of HSCs with lentivirus-mediated CRISPR/Cas9-based genetic modifications into lethally irradiated congenic mice repopulated the ablated recipient immune system with the donor immune system. In this report, we efficiently manipulated CD40 expression in LSK cells using Cas9 RNP and demonstrated the functional impact in a colitis model. Compared to a virus-based strategy, the RNP approach has the potential to enable investigation of target gene biology in any mouse strain and eliminates the time and effort associated with virus production and infection. Therefore, in vivo RNP-based CRISPR/Cas9 gene editing of transplanted HSCs represents a promising new strategy for exploring gene function in the immune system of mice.

A Phase II Trial of Lutikizumab, an Anti-Interleukin-1α/ß Dual Variable Domain Immunoglobulin, in Knee Osteoarthritis Patients With Synovitis.

OBJECTIVE: To assess the efficacy and safety of the anti-interleukin-1α/ß (anti-IL-1α/ß) dual variable domain immunoglobulin lutikizumab (ABT-981) in patients with knee osteoarthritis (OA) and evidence of synovitis. METHODS: Patients (n = 350; 347 analyzed) with Kellgren/Lawrence grade 2-3 knee OA and synovitis (determined by magnetic resonance imaging [MRI] or ultrasound) were randomized to receive placebo or lutikizumab 25, 100, or 200 mg subcutaneously every 2 weeks for 50 weeks. The coprimary end points were change from baseline in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score at week 16 and change from baseline in MRI-assessed synovitis at week 26. RESULTS: The WOMAC pain score at week 16 had improved significantly versus placebo with lutikizumab 100 mg (P = 0.050) but not with the 25 mg or 200 mg doses. Beyond week 16, the WOMAC pain score was reduced in all groups but was not significantly different between lutikizumab-treated and placebo-treated patients. Changes from baseline in MRI-assessed synovitis at week 26 and other key symptom- and most structure-related end points at weeks 26 and 52 were not significantly different between the lutikizumab and placebo groups. Injection site reactions, neutropenia, and discontinuations due to neutropenia were more frequent with lutikizumab versus placebo. Reductions in neutrophil and high-sensitivity C-reactive protein levels plateaued with lutikizumab 100 mg, with further reductions not observed with the 200 mg dose. Immunogenic response to lutikizumab did not meaningfully affect systemic lutikizumab concentrations. CONCLUSION: The limited improvement in the WOMAC pain score and the lack of synovitis improvement with lutikizumab, together with published results from trials of other IL-1 inhibitors, suggest that IL-1 inhibition is not an effective analgesic/antiinflammatory therapy in most patients with knee OA and associated synovitis.

Molecular taxonomy of osteoarthritis for patient stratification, disease management and drug development: biochemical markers associated with emerging clinical phenotypes and molecular endotypes.

PURPOSE OF REVIEW: This review focuses on the molecular taxonomy of osteoarthritis from the perspective of molecular biomarkers. We discuss how wet biochemical markers may be used to understand disease pathogenesis and progression and define molecular endotypes of osteoarthritis and how these correspond to clinical phenotypes. RECENT FINDINGS: Emerging evidence suggests that osteoarthritis is a heterogeneous and multifaceted disease with multiple causes, molecular endotypes and corresponding clinical phenotypes. Biomarkers may be employed as tools for patient stratification in clinical trials, enhanced disease management in the primary care centres of the future and for directing more rational and targeted osteoarthritis drug development. Proximal molecular biomarkers (e.g synovial fluid) are more likely to distinguish between molecular endotypes because there is less interference from systemic sources of biomarker noise, including comorbidities. SUMMARY: In this review, we have focused on the molecular biomarkers of four distinct osteoarthritis subtypes including inflammatory, subchondral bone remodelling, metabolic syndrome and senescent age-related endotypes, which have corresponding phenotypes. Progress in the field of osteoarthritis endotype and phenotype research requires a better understanding of molecular biomarkers that may be used in conjunction with imaging, pain and functional assessments for the design of more effective, stratified and individualized osteoarthritis treatments.

Phase IIa, placebo-controlled, randomised study of lutikizumab, an anti-interleukin-1α and anti-interleukin-1ß dual variable domain immunoglobulin, in patients with erosive hand osteoarthritis.

OBJECTIVE: To assess the efficacy, safety, pharmacokinetics and pharmacodynamics of the anti-interleukin (IL)-1α/ß dual variable domain immunoglobulin lutikizumab (ABT-981) in erosive hand osteoarthritis (HOA). METHODS: Patients with ≥1 erosive and ≥3 tender and/or swollen hand joints were randomised to placebo or lutikizumab 200 mg subcutaneously every 2 weeks for 24 weeks. The primary endpoint was change in Australian/Canadian Osteoarthritis Hand Index (AUSCAN) pain subdomain score from baseline to 16 weeks. At baseline and week 26, subjects had bilateral hand radiographs and MRI of the hand with the greatest number of baseline tender and/or swollen joints. Continuous endpoints were assessed using analysis of covariance models, with treatment and country as main factors and baseline measurements as covariates. RESULTS: Of 132 randomised subjects, 1 received no study drug and 110 completed the study (placebo, 61/67 (91%); lutikizumab, 49/64 (77%)). AUSCAN pain was not different among subjects treated with lutikizumab versus placebo at week 16 (least squares mean difference, 1.5 (95% CI -1.9 to 5.0)). Other clinical and imaging endpoints were not different between lutikizumab and placebo. Lutikizumab significantly decreased serum high-sensitivity C reactive protein levels, IL-1α and IL-1ß levels, and blood neutrophils. Lutikizumab pharmacokinetics were consistent with phase I studies and not affected by antidrug antibodies. Injection site reactions and neutropaenia were more common in the lutikizumab group; discontinuations because of adverse events occurred more frequently with lutikizumab (4/64) versus placebo (1/67). CONCLUSION: Despite adequate blockade of IL-1, lutikizumab did not improve pain or imaging outcomes in erosive HOA compared with placebo.

Longitudinal Reliability of the OMERACT Thumb Base Osteoarthritis Magnetic Resonance Imaging Scoring System (TOMS).

OBJECTIVE: To assess the longitudinal reliability of the Outcome Measures in Rheumatology (OMERACT) Thumb base Osteoarthritis Magnetic resonance imaging (MRI) Scoring system (TOMS). METHODS: Paired MRI of patients with hand osteoarthritis were scored in 2 exercises (6-mo and 2-yr followup) for synovitis, subchondral bone defects (SBD), osteophytes, cartilage assessment, bone marrow lesions (BML), and subluxation. Interreader reliability of delta scores was assessed. RESULTS: Little change occurred. Average-measure intraclass correlation coefficients were good-excellent (≥ 0.71), except synovitis (0.55-0.83) and carpometacarpal-1 osteophytes/cartilage assessment (0.47/0.39). Percentage exact/close agreement was 52-92%/68-100%, except BML in 2 years (28%/64-76%). Smallest detectable change was below the scoring increment, except in SBD and BML. CONCLUSION: TOMS longitudinal reliability was moderate-good. Limited change hampered assessment.

Corrigendum: The RA-MAP Consortium: a working model for academia-industry collaboration.

This corrects the article DOI: 10.1038/nrrheum.2017.200.

Timing and Impact of Decisions to Adjust Disease-Modifying Antirheumatic Drug Therapy for Rheumatoid Arthritis Patients With Active Disease.

OBJECTIVE: Guidelines recommend that rheumatoid arthritis (RA) patients with moderate-to-high disease activity (MHDAS) adjust disease-modifying antirheumatic drug (DMARD) therapy at least every 3 months until reaching low disease activity or remission (LDAS). We examined how quickly RA patients with MHDAS adjust DMARD therapy in clinical practice, and whether those who adjust DMARDs within 90 days in response to MHDAS reach LDAS sooner. METHODS: We identified RA patients with MHDAS in the University of Pittsburgh Rheumatoid Arthritis Comparative Effectiveness Research registry, and conducted a competing risks regression on time to DMARD therapy adjustment and a Cox regression on time to LDAS. RESULTS: We identified 538 eligible subjects with 943.5 patient-years of followup. Sixty percent of patients with persistent MHDAS adjusted DMARDs within 90 days. Among all subjects, median times to DMARD adjustment and LDAS were 154 (interquartile range [IQR] 1-706) days and 301 (IQR 140-706) days, respectively. Being elderly (subdistribution hazard ratio [SHR] 0.61, P = 0.02), lower baseline disease activity (SHR 0.72, P < 0.01), longer duration of RA (SHR 0.98, P < 0.01), and biologic use (SHR 0.71, P < 0.01) were significantly associated with longer times to therapy adjustment. African American race (hazard ratio [HR] 0.63, P = 0.01), higher baseline disease activity (HR 0.75, P < 0.01), and not adjusting DMARD therapy within 90 days (HR 0.76, P = 0.01) were associated with longer times to LDAS. CONCLUSION: Adjusting DMARDs within 90 days was associated with shorter times to LDAS, but many patients with persistent MHDAS waited >90 days to adjust DMARDs. Interventions are needed to address the timeliness of DMARD adjustments for RA patients with MHDAS.

Rheumatoid Arthritis Patients' Motivations for Accepting or Resisting Disease-Modifying Antirheumatic Drug Treatment Regimens.

OBJECTIVE: Patient refusal of and nonadherence to treatment with disease-modifying antirheumatic drugs (DMARDs) can adversely affect disease outcomes in rheumatoid arthritis (RA). This qualitative study describes how RA patients' feelings in response to experiences and information affected their decisions to accept (agree to adopt, initiate, and implement) or resist (refuse, avoid, and discontinue) DMARD treatment regimens. METHODS: A total of 48 RA patients were interviewed about their experiences making decisions about DMARDs. The interviews were transcribed, coded, and analyzed for themes related to their internal motivations for accepting or resisting treatment regimens, using a narrative analysis approach. RESULTS: In addition to feelings about the necessity and dangers of medications, patients' feelings towards their identity as an ill person, the act of taking medication, and the decision process itself were important drivers of patient's decisions. For patients' motivations to accept treatment regimens, 2 themes emerged: a desire to return to a normal life, and fear of future disability due to RA. For motivations to resist treatment regimens, 5 themes emerged: fear of medications, maintaining control over health, denial of sick identity, disappointment with treatment, and feeling overwhelmed by the cognitive burden of deciding. CONCLUSION: Feelings in response to experiences and information played a major role in how patients weighed the benefits and costs of treatment options, suggesting that addressing patients' feelings may be important when rheumatologists counsel about therapeutic options. Further research is needed to learn how best to address patients' feelings throughout the treatment decision-making process.

The RA-MAP Consortium: a working model for academia-industry collaboration.

Collaboration can be challenging; nevertheless, the emerging successes of large, multi-partner, multi-national cooperatives and research networks in the biomedical sector have sustained the appetite of academics and industry partners for developing and fostering new research consortia. This model has percolated down to national funding agencies across the globe, leading to funding for projects that aim to realise the true potential of genomic medicine in the 21st century and to reap the rewards of 'big data'. In this Perspectives article, the experiences of the RA-MAP consortium, a group of more than 140 individuals affiliated with 21 academic and industry organizations that are focused on making genomic medicine in rheumatoid arthritis a reality are described. The challenges of multi-partner collaboration in the UK are highlighted and wide-ranging solutions are offered that might benefit large research consortia around the world.

Soluble biochemical markers of osteoarthritis: Are we close to using them in clinical practice?

Osteoarthritis (OA) is the most common form of arthritis and a major cause of pain and disability. Recent work suggests that the global burden of OA is increasing, and costs associated with treatment are expected to increase dramatically as the aging human population expands. OA is currently diagnosed using radiography, but this technique is an indirect and insensitive measure of alterations in articular cartilage and fails to measure dynamic inflammatory processes in the joint. Radiographic changes detected overtime are small and occur in only a subset (progressors) of patients with OA. Therefore, we diagnose patients with OA on the basis of a diagnostic classification that is outdated. We also use the same tools and approaches for assessing the efficacy of new pharmacological and nonpharmacological interventions. In this review, we discuss the utility of soluble biochemical markers as biomarkers of OA and discuss whether we are close to using them in clinical practice. Combining patient information, functional imaging and carefully selected panels of biomarkers can help in achieving enhanced patient stratification and lead to better designed clinical trials. Biomarkers can be used for molecular endotyping and for developing more effective and more personalized treatments that will enhance clinical care for patients with OA.

Differential response of serum amyloid A to different therapies in early rheumatoid arthritis and its potential value as a disease activity biomarker.

BACKGROUND: The aim was to compare the effect of etanercept (ETN) and conventional synthetic disease-modifying anti-rheumatic drug (DMARD) therapy on serum amyloid A (SAA) levels and to determine whether SAA reflects rheumatoid arthritis (RA) disease activity better than C-reactive protein (CRP). METHODS: We measured SAA and CRP at baseline, 24, 48, and 102 week follow-up visits in 594 patients participating in the Treatment of early RA (TEAR) study. We used Spearman correlation coefficients (rho) to evaluate the relationship between SAA and CRP and mixed effects models to determine whether ETN and methotrexate (MTX) treatment compared to triple DMARD therapy differentially lowered SAA. Akaike information criteria (AIC) were used to determine model fits. RESULTS: SAA levels were only moderately correlated with CRP levels (rho = 0.58, p < 0.0001). There were significant differences in SAA by both visit (p = 0.0197) and treatment arm (p = 0.0130). RA patients treated with ETN plus MTX had a larger reduction in SAA than patients treated with traditional DMARD therapy. Similar results were found for serum CRP by visit (p = 0.0254) and by treatment (p < 0.0001), with a more pronounced difference than for SAA. Across all patients and time points, models of the disease activity score of 28 joints (DAS28)-erythrocyte sedimentation rate (ESR) using SAA levels were better than models using CRP; the ΔAIC between the SAA and CRP models was 305. CONCLUSIONS: SAA may be a better biomarker of RA disease activity than CRP, especially during treatment with tumor necrosis factor (TNF) antagonists. This warrants additional studies in other cohorts of patients on treatment for RA. TRIAL REGISTRATION: (ClinicalTrials.gov identifier: NCT00259610 , Date of registration: 28 November 2005).