Tofacitinib facilitates the expansion of myeloid-derived suppressor cells and ameliorates interstitial lung disease in SKG mice

Therapeutic single-cell landscape: methotrexate exacerbates interstitial lung disease by compromising the stemness of alveolar epithelial cells under systemic inflammation

BACKGROUND

Interstitial lung disease (ILD) poses a serious threat in patients with rheumatoid arthritis (RA). However, the impact of cornerstone drugs, including methotrexate (MTX) and TNF inhibitor, on RA-associated ILD (RA-ILD) remains controversial.

METHODS

Using an SKG mouse model and single-cell transcriptomics, we investigated the effects of MTX and TNF blockade on ILD.

FINDINGS

Our study revealed that MTX exacerbates pulmonary inflammation by promoting immune cell infiltration, Th17 activation, and fibrosis. In contrast, TNF inhibitor ameliorates these features and inhibits ILD progression. Analysis of data from a human RA-ILD cohort revealed that patients with ILD progression had persistently higher systemic inflammation than those without progression, particularly among the subgroup undergoing MTX treatment.

INTERPRETATION

These findings highlight the need for personalized therapeutic approaches in RA-ILD, given the divergent outcomes of MTX and TNF inhibitor.

FUNDING

This work was funded by GENINUS Inc., and the National Research Foundation of Korea, and Seoul National University Hospital.

CD206+ macrophages are relevant non-invasive imaging biomarkers and therapeutic targets in experimental lung fibrosis

BACKGROUND

Interstitial lung diseases (ILDs) include a large number of diseases associated with progressive pulmonary fibrosis (PPF), including idiopathic pulmonary fibrosis (IPF). Despite the rarity of each of the fibrotic ILDs individually, they cumulatively affect a considerable number of patients. PPF is characterised by an excessive collagen deposition leading to functional decline.

OBJECTIVES

Therapeutic options are limited to nintedanib and pirfenidone which are only able to reduce fibrosis progression. CD206-expressing M2 macrophages are involved in fibrosis progression, and whether they may be relevant therapeutic targets or biomarkers remains an open question.

RESULTS

In our study, CD206+ lung macrophages were monitored in bleomycin-induced lung fibrosis in mice by combining flow cytometry, scRNAseq and in vivo molecular imaging using a single photon emission computed tomography (SPECT) radiopharmaceutical, 99mTc-tilmanocept. The antifibrotic effect of the inhibition of M2 macrophage polarisation with a JAK inhibitor, tofacitinib, was assessed in vivo. We demonstrate that CD206-targeted in vivo SPECT imaging with 99mTc-tilmanocept was able to accurately detect and quantify the increase in CD206+ macrophages from early to advanced stages of experimental fibrosis and ex vivo in lung biopsies from patients with IPF. CD206-targeted imaging also specifically detected a decrease in CD206+ lung macrophages on nintedanib and tofacitinib treatment. Importantly, early in vivo imaging of CD206+ macrophages allowed the prediction of experimental lung fibrosis progression as well as nintedanib and tofacitinib efficacy.

CONCLUSIONS

These findings indicate that M2 macrophages may be relevant theranostic targets for personalised medicine for patients with PPF.

Cognitive improving actions of tofacitinib in a mouse model of Alzheimer disease involving TNF-α, IL-6, PI3K-Akt and GSK-3β signalling pathway

Aim and Objective: This current study investigated the significance of tofactinib in improving memory functions in a memory model of β-amyloid (Aβ)-induced dementia.Material and Methods: Aβ1-42 was injected in the brain of mice using intracerebroventricular injection and after 14 days, the learning and memory was assessed on the Morris Water maze test. Mice were treated with tofactinib (10, 20, 30 mg/kg) two days prior to Aβ1-42 injection and 14 days after Aβ injection.Results: Treatment of tofactinib significantly improved the learning (decrease in day escape latency time [ELT]) and memory (increase in time spent in target quadrant). This drug also decreased the levels of T NF-α and IL-6 along with the rise in expression of p-Akt and p-GSK-3β/GSK-3β ratio in mice brain. Co-administration of LY294002 (P I3K inhibitor) or MK-2206 2HCl (Akt inhibitor) with tofactinib (30 mg/kg) obliterated the beneficial effects of the latter by increasing T NF-α and IL-6 levels along with decreasing the p-Akt expression and p-GSK-3β/GSK-3β ratio.Conclusion: It is concluded that tofactinib improves the condition of dementia of Alzheimer's type, possibly through down regulation of T NF-α and IL-6 and instigation of P I3K-Akt-p-GSK-3β signalling system in the hippocampus of Aβ-treated mice.

JAK inhibition enhances checkpoint blockade immunotherapy in patients with Hodgkin lymphoma

Unleashing antitumor T cell activity by checkpoint inhibitor immunotherapy is effective in cancer patients, but clinical responses are limited. Cytokine signaling through the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway correlates with checkpoint immunotherapy resistance. We report a phase I clinical trial of the JAK inhibitor ruxolitinib with anti-PD-1 antibody nivolumab in Hodgkin lymphoma patients relapsed or refractory following checkpoint inhibitor immunotherapy. The combination yielded a best overall response rate of 53% (10/19). Ruxolitinib significantly reduced neutrophil-to-lymphocyte ratios and percentages of myeloid suppressor cells but increased numbers of cytokine-producing T cells. Ruxolitinib rescued the function of exhausted T cells and enhanced the efficacy of immune checkpoint blockade in preclinical solid tumor and lymphoma models. This synergy was characterized by a switch from suppressive to immunostimulatory myeloid cells, which enhanced T cell division.

Local administration of myeloid-derived suppressor cells prevents progression of immune-mediated dry eye disease

Myeloid derived suppressor cells (MDSCs) are a heterogenous population of immature hematopoietic precursors with known immunoregulatory functions. The immunosuppressive role of MDSCs has been highlighted in several inflammatory ophthalmic disorders; however, their therapeutic application in suppressing the immune-mediated changes in dry eye disease (DED) has not been studied. We observed significant reduction in antigen presenting cell (APC) frequencies and their maturation in the presence of MDSCs. Moreover, co-culturing MDSCs with T helper 17 cells (Th17) resulted in reduced Th17 frequencies and their IL-17 expression. On the contrary, MDSCs maintained regulatory T cell frequencies and enhanced their function in-vitro. Furthermore, we delineated the role of interleukin-10 (IL-10) secreted by MDSCs in their immunoregulatory functions. We confirmed these results by flow cytometry analysis and observed that treatment with MDSCs in DED mice effectively suppressed the maturation of APCs, pathogenic Th17 response, and maintained Treg function and significantly ameliorated the disease. The results in this study highlight the potential therapeutic application of MDSCs in treating refractory DED.

Myeloid-derived suppressor cell-derived osteoclasts with bone resorption capacity in the joints of arthritic SKG mice

Background

Myeloid-derived suppressor cells (MDSCs) are heterogeneous immature myeloid cells with immunosuppressive functions. It is known that MDSCs are expanded at inflammatory sites after migrating from bone marrow (BM) or spleen (Sp). In chronic inflammatory diseases such as rheumatoid arthritis (RA), previous reports indicate that MDSCs are increased in BM and Sp, but detailed analysis of MDSCs in inflamed joints is very limited.

Objective

The purpose of this study is to characterize the MDSCs in the joints of mice with autoimmune arthritis.

Methods

We sorted CD11b+Gr1+ cells from joints (Jo), bone marrow (BM) and spleen (Sp) of SKG mice with zymosan (Zym)-induced arthritis and investigated differentially expressed genes (DEGs) by microarray analysis. Based on the identified DEGs, we assessed the suppressive function of CD11b+Gr1+ cells from each organ and their ability to differentiate into osteoclasts.

Results

We identified MDSCs as CD11b+Gr1+ cells by flow cytometry and morphological analysis. Microarray analysis revealed that Jo-CD11b+Gr1+ cells had different characteristics compared with BM-CD11b+Gr1+ cells or Sp-CD11b+Gr1+ cells. Microarray and qPCR analysis showed that Jo-CD11b+Gr1+ cells strongly expressed immunosuppressive DEGs (Pdl1, Arg1, Egr2 and Egr3). Jo-CD11b+Gr1+ cells significantly suppressed CD4+ T cell proliferation and differentiation in vitro, which confirmed Jo-CD11b+Gr1+ cells as MDSCs. Microarray analysis also revealed that Jo-MDSCs strongly expressed DEGs of the NF-κB non-canonical pathway (Nfkb2 and Relb), which is relevant for osteoclast differentiation. In fact, Jo-MDSCs differentiated into osteoclasts in vitro and they had bone resorptive function. In addition, intra-articular injection of Jo-MDSCs promoted bone destruction.

Conclusions

Jo-MDSCs possess a potential to differentiate into osteoclasts which promote bone resorption in inflamed joints, while they are immunosuppressive in vitro.

Potential Rheumatoid Arthritis-Associated Interstitial Lung Disease Treatment and Computational Approach for Future Drug Development

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by swelling in at least one joint. Owing to an overactive immune response, extra-articular manifestations are observed in certain cases, with interstitial lung disease (ILD) being the most common. Rheumatoid arthritis-associated interstitial lung disease (RA-ILD) is characterized by chronic inflammation of the interstitial space, which causes fibrosis and the scarring of lung tissue. Controlling inflammation and pulmonary fibrosis in RA-ILD is important because they are associated with high morbidity and mortality. Pirfenidone and nintedanib are specific drugs against idiopathic pulmonary fibrosis and showed efficacy against RA-ILD in several clinical trials. Immunosuppressants and disease-modifying antirheumatic drugs (DMARDs) with anti-fibrotic effects have also been used to treat RA-ILD. Immunosuppressants moderate the overexpression of cytokines and immune cells to reduce pulmonary damage and slow the progression of fibrosis. DMARDs with mild anti-fibrotic effects target specific fibrotic pathways to regulate fibrogenic cellular activity, extracellular matrix homeostasis, and oxidative stress levels. Therefore, specific medications are required to effectively treat RA-ILD. In this review, the commonly used RA-ILD treatments are discussed based on their molecular mechanisms and clinical trial results. In addition, a computational approach is proposed to develop specific drugs for RA-ILD.

Diverse functions of myeloid-derived suppressor cells in autoimmune diseases

Since myeloid-derived suppressor cells (MDSCs) were found suppressing immune responses in cancer and other pathological conditions, subsequent researchers have pinned their hopes on the suppressive function against immune damage in autoimmune diseases. However, recent studies have found key distinctions of MDSC immune effects in cancer and autoimmunity. These include not only suppression and immune tolerance, but MDSCs also possess pro-inflammatory effects and exacerbate immune disorders during autoimmunity, while promoting T cell proliferation, inducing Th17 cell differentiation, releasing pro-inflammatory cytokines, and causing direct tissue damage. Additionally, MDSCs could interact with surrounding cells to directly cause tissue damage or repair, sometimes even as an inflammatory indicator in line with disease severity. These diverse manifestations could be partially attributed to the heterogeneity of MDSCs, but not all. The different disease types, disease states, and cytokine profiles alter the diverse phenotypes and functions of MDSCs, thus leading to the impairment or obversion of MDSC suppression. In this review, we summarize the functions of MDSCs in several autoimmune diseases and attempt to elucidate the mechanisms behind their actions.

Janus kinase inhibitors vs. abatacept about safety and efficacy for patients with rheumatoid arthritis-associated interstitial lung disease: a retrospective nested case-control study

BACKGROUND

Interstitial lung disease (ILD) related to rheumatoid arthritis (RA) is among the leading causes of death and an essential prognostic factor. There is only limited evidence for the safety of anti-rheumatic drugs for patients with RA-ILD. The aim of this study is to investigate the safety and efficacy of Janus kinase inhibitors (JAKis) by comparing it with abatacept (ABT) in patients with RA-ILD.

METHODS

This single centre, retrospective nested case-control study enrolled patients with RA-ILD treated with JAKi or ABT. To determine the safety of the two drugs for existing ILD, we compared their drug persistency, incidence rates of pulmonary complications, and change of chest computed tomography (CT) image. For their efficacy as RA treatment, disease activity scores and prednisolone (PSL)-sparing effect were compared. We performed propensity score matching to match the groups' patient characteristics.

RESULTS

We studied 71 patients with RA-ILD (ABT, n = 45; JAKi, n = 26). At baseline, the JAKi group had longer disease duration, longer duration of past bDMARD or JAKi use and higher usual interstitial pneumonia rate. After propensity score matching, no significant differences in patient characteristics were found between the two groups. No significant difference in the drug persistency rate for the first 2 years (ABT, 61.9%; JAKi, 42.8%; P = 0.256) was observed between the two matched groups. The incidence rate of pulmonary complications did not differ significantly between the two groups (P = 0.683). The CT score did not change after the treatment for the ABT group (Ground-glass opacities (GGO): P = 0.87; fibrosis: P = 0.78), while the GGO score significantly improved for the JAKi group (P = 0.03), although the number was limited (ABT: n = 7; JAKi: n = 8). The fibrosis score of the JAKi group did not change significantly.(P = 0.82). Regarding the efficacy for RA, a significant decrease in disease activity scores after the 1-year treatment was observed in both groups, and PSL dose was successfully tapered, although no significant differences were observed between the two drugs.

CONCLUSIONS

JAKi is as safe and effective as ABT for patients with RA-ILD. JAKi can be a good treatment option for such patients.

Tofacitinib in the treatment of primary Sjögren's syndrome-associated interstitial lung disease: study protocol for a prospective, randomized, controlled and open-label trial

INTRODUCTION

Tofacitinib, a selective inhibitor of JAK1 and/or JAK3, is considered to alleviate the pulmonary condition of primary Sjögren's syndrome (pSS)-associated interstitial lung disease (ILD) through its anti-inflammatory and antifibrotic effects.

METHODS AND ANALYSIS

This is a single-center, prospective, randomized, open-label trial. The trial will compare a 52-week course of oral tofacitinib with traditional therapy cyclophosphamide (CYC) combined with azathioprine (AZA) in the treatment of pSS-ILD. A total of 120 patients will be randomly assigned into two treatment groups with a 1:1 ratio and followed for 52 weeks from the first dose. The primary endpoint of the study is the increase of forced vital capacity (FVC) at 52 weeks. Secondary endpoints include high-resolution computed tomography (HRCT), diffusion capacity for carbon monoxide of the lung (DLCO), the Mahler dyspnea index, the health-related quality of life (HARQoL) score, the cough symptom score, EULAR Sjögren's syndrome disease activity index (ESSDAI), and safety.

DISCUSSION

This study will be the first randomized controlled trial to investigate tofacitinib compared to the traditional regimen of CYC in combination with AZA in the treatment of pSS-ILD, which will provide data on efficacy and safety and further elucidate the role of the JAK-STAT signaling pathway in the development of pSS-ILD.

ETHICS AND DISSEMINATION

Before starting the experiment, the research proposal, informed consent (ICF) and relevant documents in accordance with the ethical principles of the Helsinki Declaration and the relevant requirements of the local GCP rules for ethical approval shall be submitted to the ethics committee of the hospital. The ethical approval of this study is reviewed by the Ethics Committee of Tongji Hospital and the ethical approval number is 2021-LCYJ-007. When the experiment is completed, the results will also be disseminated to patients and the public through publishing papers in international medical journals.

TRIAL REGISTRATION

The study was registered on the Chinese Clinical Trial Registry, www.chictr.org.cn ; ID ChiCTR2000031389.

Successful Treatment of a Patient with Drug-Refractory Rheumatoid Arthritis-Associated Interstitial Lung Disease with Upadacitinib: A Case Report

Insufficient evidence exists regarding the efficacy of Janus kinase inhibitors (JAKis), a class of targeted synthetic disease-modifying anti-rheumatic drugs (tsDMARDs), in the treatment of rheumatoid arthritis (RA)-associated interstitial lung disease (ILD). Herein, we present a case of RA-ILD refractory to previous treatments that exhibited favorable response to upadacitinib. A 69-year-old man, former smoker, was diagnosed with RA-ILD based on persistent symmetric polyarthritis, elevated C-reactive protein levels and erythrocyte sedimentation rate, reduced diffusing capacity for carbon monoxide/alveolar volume (DLCO 69.9%), and bilateral ground-glass attenuation with traction bronchiectasis, predominantly in the lower lung lobe. Initial treatment with oral prednisolone and methotrexate was started; however, the patient showed worsening dyspnea, chest high-resolution computed tomography abnormalities, and decreased pulmonary function. The dose of prednisolone was increased, and methotrexate was shifted to tacrolimus; however, tacrolimus was eventually discontinued because of renal dysfunction. Subsequent treatment changes included abatacept followed by intravenous cyclophosphamide, but ILD activity continued to worsen and met the criteria of progressive pulmonary fibrosis. Approximately 4.5 years after the RA diagnosis, dyspnea, radiological abnormalities, and DLCO improved following treatment switch to upadacitinib, one of JAKis. JAKi therapy may have potential as a treatment option for refractory RA-ILD.

Etiology and Pathogenesis of Rheumatoid Arthritis-Interstitial Lung Disease

Interstitial lung disease (ILD) is one of the most serious extra-articular complications of rheumatoid arthritis (RA), which increases the mortality of RA. Because the pathogenesis of RA-ILD remains poorly understood, appropriate therapeutic strategies and biomarkers have not yet been identified. Thus, the goal of this review was to summarize and analyze the reported data on the etiology and pathogenesis of RA-ILD. The incidence of RA-ILD increases with age, and is also generally higher in men than in women and in patients with specific genetic variations and ethnicity. Lifestyle factors associated with an increased risk of RA-ILD include smoking and exposure to pollutants. The presence of an anti-cyclic citrullinated peptide antibody, high RA disease activity, and rheumatoid factor positivity also increase the risk of RA-ILD. We also explored the roles of biological processes (e.g., fibroblast-myofibroblast transition, epithelial-mesenchymal transition, and immunological processes), signaling pathways (e.g., JAK/STAT and PI3K/Akt), and the histopathology of RA involved in RA-ILD pathogenesis based on published preclinical and clinical models of RA-ILD in animal and human studies.

Inflammatory and tolerogenic myeloid cells determine outcome following human allergen challenge

Innate mononuclear phagocytic system (MPS) cells preserve mucosal immune homeostasis. We investigated their role at nasal mucosa following allergen challenge with house dust mite. We combined single-cell proteome and transcriptome profiling on nasal immune cells from nasal biopsies cells from 30 allergic rhinitis and 27 non-allergic subjects before and after repeated nasal allergen challenge. Biopsies of patients showed infiltrating inflammatory HLA-DRhi/CD14+ and CD16+ monocytes and proallergic transcriptional changes in resident CD1C+/CD1A+ conventional dendritic cells (cDC)2 following challenge. In contrast, non-allergic individuals displayed distinct innate MPS responses to allergen challenge: predominant infiltration of myeloid-derived suppressor cells (MDSC: HLA-DRlow/CD14+ monocytes) and cDC2 expressing inhibitory/tolerogenic transcripts. These divergent patterns were confirmed in ex vivo stimulated MPS nasal biopsy cells. Thus, we identified not only MPS cell clusters involved in airway allergic inflammation but also highlight novel roles for non-inflammatory innate MPS responses by MDSC to allergens in non-allergic individuals. Future therapies should address MDSC activity as treatment for inflammatory airway diseases.

A prospective observational cohort study of the efficacy of tofacitinib plus iguratimod on rheumatoid arthritis with usual interstitial pneumonia

Objectives

This study aims to assess the efficacy of tofacitinib (TOF) plus iguratimod (IGU) in rheumatoid arthritis (RA) with usual interstitial pneumonia (UIP) (RA-UIP).

Methods

This was a prospective observational cohort, single-center study. Data from 78 RA-UIP patients treated with TOF plus IGU, IGU plus conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs), and csDMARDs were analyzed. Clinically relevant responses in RA activity assessment, pulmonary function tests (PFTs), and high-resolution computed tomography (HRCT) assessment at baseline and follow-up were compared between groups to evaluate the efficacy of TOF plus IGU.

Results

A total of 78 patients were followed up for at least 6 months after treatment. There were significant changes in sedimentation rate (ESR), C reactive protein (CRP), and disease activity score (DAS) 28-CRP during the follow-up within each treatment group, but there was no statistically significant difference between the two groups. After 6 months of TOF plus IGU treatment, forced vital capacity (FVC)% (84.7 ± 14.7 vs. 90.7 ± 15.4) and HRCT fibrosis score (7.3 ± 3.4 vs. 7.0 ± 5.6) showed a significant improvement compared to the csDMARDs group (P = 0.031, P = 0.015). The TOF plus IGU-treated patients had a significantly higher regression and lower deterioration than the csDMARDs-treated patients (P = 0.026, P = 0.026) and had a significantly higher response (regression + stability), with overall response rates of 66.7% (16/24) vs. 35.7% (10/28) (P = 0.027), respectively.

Conclusion

Our results indicate that TOF plus IGU can simultaneously relieve RA and RA-UIP and be better than the csDMARDs with a higher response rate in RA-UIP, which may be a potential choice for "dual treat-to-target".

Potential of resveratrol in the treatment of interstitial lung disease

Interstitial lung disease (ILD) is a heterogeneous group of diseases characterized by lung injury caused by lung fibroblast proliferation, interstitial inflammation, and fibrosis. Different cell signal transduction pathways are activated in response to various proinflammatory or fibrotic cytokines, such as IL-6, and these cytokines are increased in different ILDs. The overexpressed cytokines and growth factors in ILD can activate TGF-β/Smad2/3/4, NF-κB, and JAK/STAT signal transduction pathways, promote the activation of immune cells, increase the release of pro-inflammatory and pro-fibrotic factors, differentiate fibroblasts into myofibroblasts, and promote the occurrence and development of ILD. This finding suggests the importance of signal transduction pathways in patients with ILD. Recent evidence suggests that resveratrol (RSV) attenuates excessive inflammation and pulmonary fibrosis by inhibiting the TGF-β/Smad2/3/4, NF-κB, and JAK/STAT signal transduction pathways and overactivation of immune cells. In this review, advances in lung protection and the underlying mechanisms of RSV are summarized, and the potential efficacy of RSV as a promising treatment option for ILD is highlighted.

Unmet needs and perspectives in rheumatoid arthritis-associated interstitial lung disease: A critical review

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by synovitis as the most common clinical manifestation, and interstitial lung disease (RA-ILD) represents one of the most common and potentially severe extra-articular features. Our current understanding of the mechanisms and predictors of RA-ILD is limited despite the demonstration that an early identification of progressive fibrosing forms is crucial to provide timely treatment with antifibrotic therapies. While high resolution computed tomography is the gold standard technique for the diagnosis and follow-up of RA-ILD, it has been hypothesized that serum biomarkers (including novel and rare autoantibodies), new imaging techniques such as ultrasound of the lung, or the application of innovative radiologic algorithms may help towards predicting and detecting early forms of diseases. Further, while new treatments are becoming available for idiopathic and connective tissue disease-associated forms of lung fibrosis, the treatment of RA-ILD remains anecdotal and largely unexplored. We are convinced that a better understanding of the mechanisms connecting RA with ILD in a subgroup of patients as well as the creation of adequate diagnostic pathways will be mandatory steps for a more effective management of this clinically challenging entity.

Tofacitinib fails to prevent T cell transfer colitis in mice but ameliorates disease activity

Tofactinib is a JAK inhibitor approved for ulcerative colitis in humans. Despite of its' proven effectiveness in humans, mechanistic data are scarce on the effectiveness of Tofactinib in experimental colitis in mice. We induced experimental colitis by transfer of CD4+CD25- isolated T cells into RAG2-/- (T and B cell deficient) mice and treated these mice with tofacitinib for 5-6 weeks either with a dosage of 10 or 40 mg/kg body weight immediately after CD4+ transfer or started treatment after first symptoms of disease for several weeks. While treatment with tofacitinib immediately after transfer resulted in an enhanced expansion of CD4+ T cells and did not prevent occurrence of colitis, treatment after start of symptoms of colitis ameliorated disease activity on a clinical basis and in histological analyses. Tofacitinib is effective in the treatment of murine experimental T cell transfer colitis, however does not prevent occurrence of disease.

Evolution of Rheumatoid-Arthritis-Associated Interstitial Lung Disease in Patients Treated with JAK Inhibitors: A Retrospective Exploratory Study

BACKGROUND

The aim of this multicenter retrospective study was to investigate the effectiveness and safety of the available JAK-inhibitors (JAKi) in patients with rheumatoid arthritis (RA) and interstitial lung disease (ILD).

METHODS

We retrospectively analyzed patients with classified RA and RA-ILD undergoing JAKi in 6 Italian tertiary centers from April 2018 to June 2022. We included patients with at least 6 months of active therapy and one high-resolution chest tomography (HRCT) carried out within 3 months of the start of JAKi treatment. The HRCT was then compared to the most recent one carried out within 3 months before the last available follow-up appointment. We also kept track of the pulmonary function tests.

RESULTS

We included 43 patients with RA-ILD and 23 males (53.48%) with a median age (interquartile range, IQR) of 68.87 (61.46-75.78) treated with JAKi. The median follow-up was 19.1 months (11.03-34.43). The forced vital capacity remained stable in 22/28 (78.57%) patients, improved in 3/28 (10.71%) and worsened in 3/28 (10.71%). The diffusing capacity of lung for carbon monoxide showed a similar trend, remaining stable in 18/25 (72%) patients, improving in 2/25 (8%) and worsening in 5/25 (20%). The HRCT remained stable in 37/43 (86.05) cases, worsened in 4/43 (9.30%) and improved in the last 2 (4.65%).

DISCUSSION

This study suggests that JAKi therapy might be a safe therapeutic option for patients with RA-ILD in a short-term follow-up.

Interstitial lung disease in rheumatoid arthritis: A multidisciplinary problem in rheumatology and pulmonology

Rheumatoid arthritis (RA) is an immune-mediated rheumatic disease (IMRDs) characterized by chronic erosive arthritis and systemic damage to internal organs, leading to early disability and reduced life expectancy in patients. A particularly important place among the systemic manifestations of RA is occupied by interstitial lung diseases (ILD) – the most severe form of pulmonary pathology in RA, defined as RA-ILD, which is pathogenetically associated with risk factors (smoking, etc.) and autoimmune mechanisms underlying RA. RA-ILD is a subtype of RA characterized by a severe course and a poor prognosis и неблагоприятным прогнозом. The review presents new data regarding risk factors and biomarkers for RA-ILD; modern diagnostic capabilities based on the use of functional lung tests, high-resolution computed tomography, ultrasound examination of the lungs. Particular attention is paid to the efficacy and safety of pharmacotherapy, including methotrexate, biologics, JAK inhibitors, and antifibrotic therapy. An algorithm for the pharmacotherapy of RA-ILD has been proposed.

Pseudolycorine chloride ameliorates Th17 cell-mediated central nervous system autoimmunity by restraining myeloid-derived suppressor cell expansion

CONTEXT

The alkaloids of Narcissus tazetta L. var. Chinensis Roem (Amaryllidaceae) have antitumor and antiviral activities. However, the immunopharmacological effects of one of its constituents, pseudolycorine chloride (PLY), have not been reported yet.

OBJECTIVE

We evaluated the effect of PLY on myeloid-derived suppressor cells (MDSCs) expansion and differentiation into monocyte-like MDSCs (M-MDSCs) and examined whether PLY alleviates Th17 cell-mediated experimental autoimmune encephalomyelitis (EAE), a murine model of multiple sclerosis (MS).

MATERIALS AND METHODS

In vitro, MDSCs were treated with PLY (0.67, 2 and 6 μM) or solcitinib (10 μM, positive control) for 48 or 96 h, and their proliferation, expansion, and differentiation into M-MDSCs were examined by flow cytometry. Myelin oligodendrocyte glycoprotein (MOG_35-55) was used to induce EAE in female C57BL/6 mice, and the mice were treated with 40 mg/kg/d PLY or 1 mg/kg/d FK-506 (tacrolimus, positive control) for 21 days. Inflammatory infiltration, spinal cord demyelination, and MDSCs and Th17 cells infiltration into the spinal cord were examined using haematoxylin and eosin staining, Luxol fast blue staining, and immunofluorescence, respectively.

RESULTS

In vitro, PLY (IC50/24 h = 6.18 μM) significantly inhibited IL-6 and GM-CSF-induced MDSCs proliferation, expansion and differentiation into M-MDSCs at all concentrations used. However, these concentrations did not show cytotoxicity. In mice, PLY (40 mg/kg) treatment alleviated EAE and inhibited inflammatory infiltration, demyelination, and MDSCs and Th17 cells infiltration into the spinal cord.

DISCUSSION AND CONCLUSIONS

PLY may be an excellent candidate for the treatment of MS and other autoimmune diseases.

Pharmacological modulation of myeloid-derived suppressor cells to dampen inflammation

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous cell population with potent suppressive and regulative properties. MDSCs’ strong immunosuppressive potential creates new possibilities to treat chronic inflammation and autoimmune diseases or induce tolerance towards transplantation. Here, we summarize and critically discuss different pharmacological approaches which modulate the generation, activation, and recruitment of MDSCs in vitro and in vivo, and their potential role in future immunosuppressive therapy.

Pulmonary fibrosis associated with rheumatoid arthritis: from pathophysiology to treatment strategies

INTRODUCTION

Rheumatoid arthritis (RA) is the most common inflammatory autoimmune disease, characterised by symmetric destructive arthritis and synovitis. Lung involvement is frequent, including in the form of interstitial lung disease (ILD). RA-ILD often presents with a radiologic and pathologic pattern of usual interstitial pneumonia, similar to idiopathic pulmonary fibrosis, highlighting the similarities between the two diseases, but other patterns and pathological associations are described.

AREAS COVERED

This article reviews the pathogenesis of pulmonary fibrosis in the setting of rheumatoid arthritis as well as the current and future therapeutic options.

EXPERT OPINION

Pulmonary fibrosis in the setting of RA-ILD is an example of genotype-environment interaction and involves multiple mechanisms including autoimmunity, inflammation and fibrogenesis. Despite that ILD conveys most of the exceeding mortality in RA patients, there are no official guidelines for the management of RA-ILD. Attention should be paid to potential lung toxicity of RA treatment even though some of them might help stabilise the ILD. Current standard of care is often composed of glucocorticoids that may be associated with immunosuppressive therapy. Following the approval of antifibrotic therapy for ILDs with a progressive fibrosing phenotype, current works are evaluating the benefit of such treatment in RA-ILD.

A retrospective study of the efficacy of JAK inhibitors or abatacept on rheumatoid arthritis-interstitial lung disease

Objectives

To examine the effectiveness of Janus-kinase inhibitors (JAKis) or abatacept (ABA) in patients with rheumatoid arthritis-interstitial lung disease (RA-ILD).

Methods

Patients with RA-ILD receiving JAKis or ABA were retrospectively evaluated at baseline and after 18 months of treatment. A computer-aided method (CaM) was used to assess the extent of high-resolution computed tomography (HRCT) fibrosis percentage. According to HRCT fibrosis changes, patients were classified as “worsened” (progression of 15% or more), “stable” (changes within 15%) or “improved” (reduction of 15% or more). Correlations between RA characteristics and JAKis or ABA responses were studied using a multivariate regression model.

Results

Seventy-five patients (69.3% women) were evaluated, 31 received a JAKi while 44 received ABA. In the JAKis group, five patients (16.1%) showed RA-ILD progression, 20 patients (64.5%) were considered stable, and six patients (19.4%) demonstrated RA-ILD improvement. In the ABA group, five patients (11.3%) showed RA-ILD progression, 32 patients (72.7%) were stable, and seven patients (16.0%) demonstrated RA-ILD improvement. In both groups, the percentage of current smokers was different between those classified as "worsened" and those classified as "improved/stable" (p = 0.01). In multivariate regression analysis, current smoking habit (p = 0.0051) and concomitant methotrexate treatment (p = 0.0078) were the two variables related to RA-ILD progression in ABA-treated patients, whereas in JAKis-treated patients, the only RA-ILD progression-related variable was disease duration of RA (p < 0.001).

Conclusions

Treatment with JAKis or ABA was related to stability or improvement of RA-ILD in 83.9% and 88.6% of patients, respectively. RA duration is the only variable associated with worsening RA-ILD in JAKis-treated patients.

Therapeutic Potential of Janus Kinase Inhibitors for the Management of Interstitial Lung Disease

Interstitial lung disease (ILD) refers to a heterogeneous group of diseases characterized by lung fibroblast proliferation, interstitial inflammation, and fibrosis-induced lung damage. The Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway is known to be activated by pro-fibrotic/pro-inflammatory cytokines such as IL-6 and IL-13, whose levels are elevated in ILD. The overexpression of growth factors such as transforming growth factor β1 in ILD activates the JAK/STAT pathway through classical or non-classical pathways, promotes macrophage activation, increases the release of pro-inflammatory and pro-fibrosis factors, and facilitates fibroblast differentiation into myofibroblasts. These findings implicate that the JAK/STAT pathway plays an important role in the course of ILD. Recent evidence also suggests that JAK inhibition alleviates excessive inflammation and pulmonary fibrosis. Accordingly, the JAK inhibitors may serve as promising drugs for the treatment of JAK/STAT-induced ILD.

The role of antifibrotics in the treatment of rheumatoid arthritis-associated interstitial lung disease

The major pulmonary complication of rheumatoid arthritis (RA) is interstitial lung disease (ILD), which causes significant morbidity and mortality and influences the natural course of disease. Recent advances in the management of arthritis have improved patient outcomes. However, exceptionally high medical needs still remain for effective therapies for the patients with ILD in RA. Better understanding of the shared and distinct pathophysiology of fibrotic diseases led to the development of novel antifibrotic agents such as nintedanib and pirfenidone. The further stratification analysis of the phase III INBUILD trial demonstrated beneficial effects of nintedanib in RA-ILD with a progressive phenotype by reducing the rate of decline in forced vital capacity (FVC) over 52 weeks by 60%. Pirfenidone is another antifibrotic agent currently under phase II clinical study (TRAIL1) aiming to evaluate its effects for RA-ILD. This review provides an overview of state-of-the-art pathogenesis and the current therapeutic options for RA-ILD, with a focus on antifibrotic strategies.

Tofacitinib Blocks Entheseal Lymphocyte Activation and Modulates MSC Adipogenesis, but Does Not Directly Affect Chondro- and Osteogenesis

Entheseal spinal inflammation and new bone formation with progressive ankylosis may occur in ankylosing spondylitis (AS) and psoriatic arthritis (PsA). This study evaluated whether JAK inhibition with tofacitinib modulated the key disease associated cytokines, TNF and IL-17A, and whether tofacitinib also modulated bone marrow stromal cell-derived mesenchymal stem cell (MSCs) function, including osteogenesis, since post inflammation new bone formation occurs under these conditions. Methods: Conventional entheseal derived αβ CD4+ and CD8+ T-cells were investigated following anti-CD3/CD28 bead stimulation to determine IL-17A and TNF levels in tofacitinib treated (1000 nM) peri-entheseal bone (PEB) and peripheral blood mononuclear cells (PBMC) using ELISA. Bone marrow stromal cell-derived mesenchymal stem cell (MSC) colony forming units (CFU-F) and multi-lineage potential were evaluated using tofacitinib (dosages ranging between 100, 500, 1000 and 10,000 nM). Results: Induced IL-17A and TNF cytokine production from both entheseal CD4+ T-cells and CD8+ T-cells was effectively inhibited by tofacitinib. Tofacitinib treatment did not impact on CFU-F potential or in vitro chondro- and osteogenesis. However, tofacitinib stimulation increased MSC adipogenic potential with greater Oil Red O stained areas. Conclusion: Inducible IL-17A and TNF production by healthy human entheseal CD4+ and CD8+ T-cells was robustly inhibited in vitro by tofacitinib. However, tofacitinib did not impact MSC osteogenesis, but stimulated in vitro MSC adipogenesis, the relevance of which needs further evaluation given that the adipocytes are associated with new bone formation in SpA.

Myeloid-derived suppressor cells in the era of increasing myeloid cell diversity

Myeloid-derived suppressor cells (MDSCs) are pathologically activated neutrophils and monocytes with potent immunosuppressive activity. They are implicated in the regulation of immune responses in many pathological conditions and are closely associated with poor clinical outcomes in cancer. Recent studies have indicated key distinctions between MDSCs and classical neutrophils and monocytes, and, in this Review, we discuss new data on the major genomic and metabolic characteristics of MDSCs. We explain how these characteristics shape MDSC function and could facilitate therapeutic targeting of these cells, particularly in cancer and in autoimmune diseases. Additionally, we briefly discuss emerging data on MDSC involvement in pregnancy, neonatal biology and COVID-19.

A short course of tofacitinib sustains the immunoregulatory effect of CTLA4-Ig in the presence of inflammatory cytokines and promotes long-term survival of murine cardiac allografts

Costimulation blockade-based regimens are a promising strategy for management of transplant recipients. However, maintenance immunosuppression via CTLA4-Ig monotherapy is characterized by high frequency of rejection episodes. Recent evidence suggests that inflammatory cytokines contribute to alloreactive T cell activation in a CD28-independent manner, a reasonable contributor to the limited efficacy of CTLA4-Ig. In this study, we investigated the possible synergism of a combined short-term inhibition of cytokine signaling and CD28 engagement on the modulation of rejection. Our results demonstrate that the JAK/STAT inhibitor tofacitinib restored the immunomodulatory effect of CTLA4-Ig on mouse alloreactive T cells in the presence of inflammatory cytokines. Tofacitinib exposure conferred dendritic cells with a tolerogenic phenotype reducing their cytokine secretion and costimulatory molecules expression. JAK inhibition also directly affected T cell activation. In vivo, the combination of CTLA4-Ig and tofacitinib induced long-term survival of heart allografts and, importantly, it was equally effective when using grafts subjected to prolonged ischemia. Transplant survival correlated with a reduction in effector T cells and intragraft accumulation of regulatory T cells. Collectively, our studies demonstrate a powerful synergism between CTLA4-Ig and tofacitinib and suggest their combined use is a promising strategy for improved management of transplanted patients.

Role of JAK/STAT in Interstitial Lung Diseases; Molecular and Cellular Mechanisms

Interstitial lung diseases (ILDs) comprise different fibrotic lung disorders characterized by cellular proliferation, interstitial inflammation, and fibrosis. The JAK/STAT molecular pathway is activated under the interaction of a broad number of profibrotic/pro-inflammatory cytokines, such as IL-6, IL-11, and IL-13, among others, which are increased in different ILDs. Similarly, several growth factors over-expressed in ILDs, such as platelet-derived growth factor (PDGF), transforming growth factor β1 (TGF-β1), and fibroblast growth factor (FGF) activate JAK/STAT by canonical or non-canonical pathways, which indicates a predominant role of JAK/STAT in ILDs. Between the different JAK/STAT isoforms, it appears that JAK2/STAT3 are predominant, initiating cellular changes observed in ILDs. This review analyzes the expression and distribution of different JAK/STAT isoforms in ILDs lung tissue and different cell types related to ILDs, such as lung fibroblasts and alveolar epithelial type II cells and analyzes JAK/STAT activation. The effect of JAK/STAT phosphorylation on cellular fibrotic processes, such as proliferation, senescence, autophagy, endoplasmic reticulum stress, or epithelial/fibroblast to mesenchymal transition will be described. The small molecules directed to inhibit JAK/STAT activation were assayed in vitro and in in vivo models of pulmonary fibrosis, and different JAK inhibitors are currently approved for myeloproliferative disorders. Recent evidence indicates that JAK inhibitors or monoclonal antibodies directed to block IL-6 are used as compassionate use to attenuate the excessive inflammation and lung fibrosis related to SARS-CoV-2 virus. These altogether indicate that JAK/STAT pathway is an attractive target to be proven in future clinical trials of lung fibrotic disorders.

Rheumatoid arthritis related interstitial lung disease

INTRODUCTION

Interstitial lung disease (ILD) represents a frequent extra-articular manifestation of rheumatoid arthritis (RA) deeply impacting both quality of life and overall prognosis. Areas covered: A literature search was performed including PubMed, Embase, Scopus, and Web of Science. Many retrospective studies investigated the possible risk factors for RA-related ILD (RA-ILD), aiming to identify patients at risk. Among them, males, smokers, positivity of anti-citrullinated peptide antibodies have been associated with RA-ILD, such as some genetic haplotypes. Usual interstitial pneumonia is the histologic and radiologic pattern most frequently observed, followed by nonspecific interstitial pneumonia. Since lung involvement can represent the RA onset, an early differential diagnosis with idiopathic interstitial pneumonia can be difficult or sometimes impossible. High-resolution computed tomography represents the gold standard for ILD diagnosis, while multidisciplinary discussion should be required to assess disease staging, severity and progression.  Expert opinion: Management of RA-ILD patients is challenging due to the lack of evidence-based data regarding both assessment and treatment. Moreover, the high variability of clinical presentation and evolution makes it difficult to establish the correct therapeutic strategy. Currently, multidisciplinary approach, including at least rheumatologists, pulmonologists, and radiologists, is desirable to define therapy and follow-up strategies.

Tofacitinib for the Treatment of Severe Interstitial Lung Disease Related to Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease characterized by chronic symmetrical erosive synovitis and extra-articular manifestations, including interstitial lung disease (ILD), whose treatment is nowadays challenging due to high infectious risk and possible pulmonary iatrogenic toxicity. Janus kinase inhibitors, namely, tofacitinib, baricitinib, and upadacitinib, are the latest drug class for the treatment of RA with a good safety profile. We present the case of a patient with RA-ILD successfully treated with tofacitinib. A 52-year-old man was referred to our multidisciplinary clinic for rheumatic and pulmonary diseases for an active erosive seropositive RA and progressive ILD. Previous treatments were GC, hydroxychloroquine, methotrexate, etanercept, withdrawn after ILD detection, and tocilizumab, discontinued due to relapsing infections. After our evaluation, we proposed rituximab in addition to low-dose GC and hydroxychloroquine, ineffective on joint involvement. Therefore, we proposed tofacitinib which allowed us to control joint involvement, stabilize ILD improving respiratory symptoms, and manage the frequent infectious episodes that occurred initially. The short half-life and rapid-acting of tofacitinib are two helpful characteristics regarding this aspect. Despite limited data from randomized trials and real-life, tofacitinib could represent a safe therapeutic option for RA-ILD patients. Longitudinal studies are required to confirm this encouraging report.

High-throughput analysis of lung immune cells in a combined murine model of agriculture dust-triggered airway inflammation with rheumatoid arthritis

Rheumatoid arthritis (RA)-associated lung disease is a leading cause of mortality in RA, yet the mechanisms linking lung disease and RA remain unknown. Using an established murine model of RA-associated lung disease combining collagen-induced arthritis (CIA) with organic dust extract (ODE)-induced airway inflammation, differences among lung immune cell populations were analyzed by single cell RNA-sequencing. Additionally, four lung myeloid-derived immune cell populations including macrophages, monocytes/macrophages, monocytes, and neutrophils were isolated by fluorescence cell sorting and gene expression was determined by NanoString analysis. Unsupervised clustering revealed 14 discrete clusters among Sham, CIA, ODE, and CIA+ODE treatment groups: 3 neutrophils (inflammatory, resident/transitional, autoreactive/suppressor), 5 macrophages (airspace, differentiating/recruited, recruited, resident/interstitial, and proliferative airspace), 2 T-cells (differentiating and effector), and a single cluster each of inflammatory monocytes, dendritic cells, B-cells and natural killer cells. Inflammatory monocytes, autoreactive/suppressor neutrophils, and recruited/differentiating macrophages were predominant with arthritis induction (CIA and CIA+ODE). By specific lung cell isolation, several interferon-related and autoimmune genes were disproportionately expressed among CIA and CIA+ODE (e.g. Oasl1, Oas2, Ifit3, Gbp2, Ifi44, and Zbp1), corresponding to RA and RA-associated lung disease. Monocytic myeloid-derived suppressor cells were reduced, while complement genes (e.g. C1s1 and Cfb) were uniquely increased in CIA+ODE mice across cell populations. Recruited and inflammatory macrophages/monocytes and neutrophils expressing interferon-, autoimmune-, and complement-related genes might contribute towards pro-fibrotic inflammatory lung responses following airborne biohazard exposures in setting of autoimmune arthritis and could be predictive and/or targeted to reduce disease burden.

Immunomodulating role of the JAKs inhibitor tofacitinib in a mouse model of bleomycin-induced scleroderma

BACKGROUND

Janus kinase (JAK)-signal transducer and activator of transcription (STAT) was hyperactivated in biopsies from patients with systemic sclerosis (SSc) and in several autoimmune disease models. Tofacitinib, a pan-JAK inhibitor, blocks the downstream signaling of multiple cytokines and has exhibited therapeutic efficacy in various autoimmune diseases, although its immunomodulating property in scleroderma is unclear.

OBJECTIVE

To evaluate the effect of tofacitinib on the modulation of cytokine-producing T and B cells, and proinflammatory cells in a mouse model of SSc.

METHODS

Bleomycin (BLM)-induced SSc was generated by intradermal injection of BLM or PBS for control. Mice received intraperitoneal tofacitinib (20 mg/kg) or vehicle 3 times per week from day 0-28. Mice were sacrificed at day 28 after the last BLM/PBS injection.

RESULTS

Tofacitinib administration significantly alleviated fibrosis of the skin and lungs in scleroderma mouse model. Furthermore, tofacitinib suppressed adaptive and innate immune responses by reducing splenocytes, total lymphocytes, CD4⁺ T helper cells (especially Th2 and Th17 subtypes), IL-6-producing effector B cells, PDCA-1⁺ dendritic cells in the spleen, and infiltration of F4/80⁺, CD206⁺ and CD163⁺ macrophages in the skin and lungs. Conversely, tofacitinib increased the proportions of splenic regulatory T and B cells. The mRNA expression of extracellular matrix proteins and fibrogenic cytokines was downregulated by tofacitinib in both the skin and lungs.

CONCLUSION

These observations suggest JAK inhibition as a therapeutic approach for the treatment of inflammatory and fibrotic diseases, and highlight the potential of tofacitinib as a promising candidate for treating patients with scleroderma.

Air pollutants and development of interstitial lung disease in patients with connective tissue disease: a population-based case-control study in Taiwan

OBJECTIVE

The aim of this study was to assess the association between air pollutant exposure and interstitial lung disease (ILD) in patients with connective tissue diseases (CTDs).

SETTING

A nationwide, population-based, matched case-control study in Taiwan.

PARTICIPANTS

Using the 1997-2013 Taiwanese National Health Insurance Research Database, we identified patients with newly diagnosed CTD during 2001-2013, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), systemic sclerosis (SSc), dermatomyositis (DMtis)/polymyositis (PM) and primary Sjögren's syndrome (pSS).

PRIMARY AND SECONDARY OUTCOME MEASURES

Patients with newly diagnosed ILD during 2012-2013 were identified as ILD cases, and selected patients with CTD without ILD matching (1:4) the CTD cases for CTD diagnosis, age, gender, disease duration and year of ILD diagnosis date were identified as non-ILD controls. Data of hourly level of air pollutants 1 year before the index date were obtained from the Taiwan Environmental Protection Agency. The association between ILD and air pollutant exposure was evaluated using logistic regression analysis shown as adjusted ORs (aORs) with 95% CIs after adjusting for potential confounders.

RESULTS

We identified 505 newly diagnosed CTD-ILD patients, including 82 with SLE, 210 with RA, 47 with SSc, 44 with DMtis/PM and 122 with pSS. Ozone (O₃) exposure (per 10 ppb) was associated with a decreased ILD risk in patients with CTD (aOR, 0.51; 95% CI, 0.33 to 0.79) after adjusting for potential confounders.

CONCLUSIONS

A previously unrecognised inverse correlation was found between O₃ exposure and ILD in patients with RA and SSc. Further studies are warranted to explore the underlying mechanisms.

Histone Deacetylase 3-Mediated Inhibition of microRNA-19a-3p Facilitates the Development of Rheumatoid Arthritis-Associated Interstitial Lung Disease

Histone deacetylase (HDAC) has been implicated in rheumatoid arthritis (RA) progression. We investigated the roles of histone deacetylase 3 (HDAC3) involved in RA-associated interstitial lung disease (ILD) fibrosis. Firstly, we measured the expression of HDAC3 and interleukin 17 receptor A (IL17RA) in lung tissue samples from normal controls, idiopathic pulmonary fibrosis (IPF) patients, and RA-ILD patients. Next, chromatin immunoprecipitation (ChIP) and dual luciferase reporter assay were employed to detect the interaction between HDAC3 and microRNA-19a-3p (miR-19a-3p) and between miR-19a-3p and IL17RA. Further, immunohistochemistry was used to localize HDAC3 and IL17RA expression in lung tissues. Additionally, functional assays were conducted followed by expression determination of HDAC3, miR-19a-3p, and IL17RA with reverse transcription quantitative PCR (RT-qPCR) and Western blot analysis. The effect of HDAC3 on RA-ILD in the constructed RA-ILD mouse model was also studied based on arthritis assessment. We found overexpressed HDAC3 and IL17RA as well as silenced miR-19a-3p in RA-ILD mouse model and RA-ILD patients. In the mouse model, HDAC3 downregulated miR-19a-3p in lung fibroblasts to promote the progression of RA-ILD fibrosis. In lung fibroblasts of RA-ILD mice, IL17RA was a target gene of miR-19a-3p. miR-19a-3p negatively regulated IL17RA, thereby increasing the expression of fibrosis markers, COL1A1, COL3A1, and FN, in lung fibroblasts of mice. Taken together, HDAC3 upregulated IL17RA expression by targeting miR-19a-3p to facilitate the RA-ILD fibrosis development, which sheds light on a new HDAC3/miR-19a-3p/IL17RA axis functioning in RA-ILD fibrosis.

Update on the Safety Profile of Tofacitinib in Rheumatoid Arthritis from Clinical Trials to Real-World Studies: A Narrative Review

Tofacitinib is approved for the treatment of moderate to severe active rheumatoid arthritis (RA) in adult patients who do not respond adequately or are intolerant to one or more disease-modifying anti-rheumatic drugs. The tofacitinib RA clinical development program included randomized controlled trials of 6–24-month duration and long-term extension studies with > 7061 patients and 22,875 patient-years of exposure. To date, there are no data from other randomized studies in patients with cardiovascular risk factors comparing the long-term safety of a JAK inhibitor versus an anti-TNF. Real-world studies are necessary to complete the body of evidence supporting the effectiveness and safety of a therapeutic agent. In the case of tofacitinib, real-world data derive from health insurance claims databases, registries (US Corrona Registry, Swiss Registry, and others), national pharmacovigilance programs, and hospital databases (case series). The present article provides complete and up-to-date information on the safety profile of tofacitinib in RA, from clinical trials to real-world studies. Tofacitinib has demonstrated a consistent safety profile during up to 9.5 years of experience in randomized controlled trials and long-term extension studies. Real-world evidence has not added new safety issues with respect to those found in the clinical program. In general, the safety profile of tofacitinib is consistent with that of biologic disease-modifying anti-rheumatic drugs, with an increased risk of herpes zoster that seems to be a class effect of Janus kinase inhibitors. The continuous follow-up of therapeutic agents to treat rheumatoid arthritis is needed to adequately establish the safety profile for new mechanisms of action and potential risks associated with their longer term use.

The Immunoregulatory Role of Myeloid-Derived Suppressor Cells in the Pathogenesis of Rheumatoid Arthritis

Myeloid-derived suppressor cells (MDSCs) are a group of cells that regulate the immune response and exert immunosuppressive effects on various immune cells. Current studies indicate that MDSCs have both anti-inflammatory effects and proinflammatory effects on rheumatoid arthritis (RA) and RA animal models. MDSCs inhibit CD4+ T cells, which secrete proinflammatory factors such as IFN-γ, IL-2, IL-6, IL-17, and TNF-α, by inhibiting iNOS, ROS, and IFN-γ and promoting the production of the anti-inflammatory factor IL-10. MDSCs can suppress dendritic cells by reducing MHC-II and CD86 expression, expand Treg cells in vitro through the action of IL-10, inhibit B cells through NO and PGE2, and promote Th17 cell responses by secreting IL-1β. As a type of osteoclast precursor cell, MDSCs can differentiate into osteoclasts through activation of the NF-κB pathway via IL-1α. Overall, our study reviews the research progress related to MDSCs in RA, focusing on the effects of MDSCs on various types of cells and aiming to provide ideas to help reveal the important role of MDSCs in RA.

Recent advances in rheumatoid arthritis-associated interstitial lung disease

PURPOSE OF REVIEW

To provide an overview of recent studies that could be helpful in a better understanding of rheumatoid arthritis-associated interstitial lung disease (RA-ILD) and to facilitate the clinical management of this severe complication of RA.

RECENT FINDINGS

The advances in deciphering the genetic architecture of RA-ILD support the hypothesis of RA-ILD as a complex disease with a complex phenotype encompassing at least the usual interstitial pneumonia (UIP) high-resolution CT pattern and non-UIP. Genetics studies have provided evidence for a shared genetic background in idiopathic pulmonary fibrosis (IPF) and RA-ILD, and more specifically RA-UIP, a disease with high morbidity and mortality. These findings support the rationale for common pathogenic pathways opening new avenues for future intervention in RA-ILD, notably with - drugs that proved active in IPF. In agreement, a recent controlled trial suggests efficacy of nintedanib, an antifibrotic drug, in patients with progressive lung fibrosis, including RA-ILD. However, there is a substantial gap in RA-ILD treatment, notably evaluating the effect of the RA treatments on the ILD course because of no controlled trial yet.

SUMMARY

The phenotypical, environmental, and genetic similarities between IPF and RA-ILD have led to a better understanding of the underlying pathogenesis of RA-ILD. Despite the identification of several biomarkers and useful screening tools, several questions remain unanswered regarding the identification of patients with RA at increased risk of ILD and risk of progression. Other substantial gaps are the lack of recommendations for how high-risk patients should be screened and which specific therapeutic strategy should be initiated. International collaborative efforts are needed to address these issues and develop specific recommendations for RA-ILD.

Targeting the Immune System for Pulmonary Inflammation and Cardiovascular Complications in COVID-19 Patients

In December 2019, following a cluster of pneumonia cases in China caused by a novel coronavirus (CoV), named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the infection disseminated worldwide and, on March 11th, 2020, the World Health Organization officially declared the pandemic of the relevant disease named coronavirus disease 2019 (COVID-19). In Europe, Italy was the first country facing a true health policy emergency, and, as at 6.00 p.m. on May 2nd, 2020, there have been more than 209,300 confirmed cases of COVID-19. Due to the increasing number of patients experiencing a severe outcome, global scientific efforts are ongoing to find the most appropriate treatment. The usefulness of specific anti-rheumatic drugs came out as a promising treatment option together with antiviral drugs, anticoagulants, and symptomatic and respiratory support. For this reason, we feel a duty to share our experience and our knowledge on the use of these drugs in the immune-rheumatologic field, providing in this review the rationale for their use in the COVID-19 pandemic.

Combined anti-fibrotic and anti-inflammatory properties of JAK-inhibitors on macrophages in vitro and in vivo: Perspectives for scleroderma-associated interstitial lung disease

Janus kinase (JAK) inhibitors (also termed Jakinibs) constitute a family of small drugs that target various isoforms of JAKs (JAK1, JAK2, JAK3 and/or tyrosine kinase 2 (Tyk2)). They exert anti-inflammatory properties linked, in part, to the modulation of the activation state of pro-inflammatory M1 macrophages. The exact impact of JAK inhibitors on a wider spectrum of activation states of macrophages is however still to be determined, especially in the context of disorders involving concomitant activation of pro-inflammatory M1 macrophages and profibrotic M2 macrophages. This is especially the case in autoimmune pulmonary fibrosis like scleroderma-associated interstitial lung disease (ILD), in which M1 and M2 macrophages play a key pathogenic role. In this study, we directly compared the anti-inflammatory and anti-fibrotic effects of three JAK inhibitors (ruxolitinib (JAK2/1 inhibitor); tofacitinib (JAK3/2 inhibitor) and itacitinib (JAK1 inhibitor)) on five different activation states of primary human monocyte-derived macrophages (MDM). These three JAK inhibitors exert anti-inflammatory properties towards macrophages, as demonstrated by the down-expression of key polarization markers (CD86, MHCII, TLR4) and the limited secretion of key pro-inflammatory cytokines (CXCL10, IL-6 and TNFα) in M1 macrophages activated by IFNγ and LPS or by IFNγ alone. We also highlighted that these JAK inhibitors can limit M2a activation of macrophages induced by IL-4 and IL-13, as notably demonstrated by the down-regulation of the M2a associated surface marker CD206 and of the secretion of CCL18. Moreover, these JAK inhibitors reduced the expression of markers such as CXCL13, MARCO and SOCS3 in alternatively activated macrophages induced by IL-10 and dexamethasone (M2c + dex) or IL-10 alone (M2c MDM). For all polarization states, Jakinibs with inhibitory properties over JAK2 had the highest effects, at both 1 μM or 0.1 μM. Based on these in vitro results, we also explored the effects of JAK2/1 inhibition by ruxolitinib in vivo, on mouse macrophages in a model of HOCl-induced ILD, that mimics scleroderma-associated ILD. In this model, we showed that ruxolitinib significantly prevented the upregulation of pro-inflammatory M1 markers (TNFα, CXCL10, NOS2) and pro-fibrotic M2 markers (Arg1 and Chi3L3). These results were associated with an improvement of skin and pulmonary involvement. Overall, our results suggest that the combined anti-inflammatory and anti-fibrotic properties of JAK2/1 inhibitors could be relevant to target lung macrophages in autoimmune and inflammatory pulmonary disorders that have no efficient disease modifying drugs to date.

Management issues in rheumatoid arthritis-associated interstitial lung disease

PURPOSE OF REVIEW

Summarize recent evidence on the identification and management of rheumatoid arthritis-associated interstitial lung disease (RA-ILD).

RECENT FINDINGS

Clinical and subclinical interstitial lung disease (ILD) are frequent extra-articular manifestations of rheumatoid arthritis (RA). Better means of identifying and treating RA-ILD are needed to improve the prognosis, with a median survival of only 3-7 years after diagnosis. Several serum biomarkers are currently being evaluated for their ability to detect RA-ILD. Thorough evaluation and multidisciplinary discussion remains the gold standard for establishing the diagnosis of RA-ILD. Management is challenging with most RA disease-modifying antirheumatic drugs (DMARDs) linked to pneumonitis. Methotrexate is typically avoided in clinically significant ILD, although alternative therapies including leflunomide and biologic DMARDs also carry risks in RA-ILD. Antifibrotics appear to slow the progression of ILD, and a large phase II trial exclusively in RA-ILD is underway. In addition, smoking cessation, pulmonary rehabilitation, oxygen therapy, managing comorbidities, and lung transplantation evaluation are vital to improving patient outcomes in RA-ILD.

SUMMARY

With little high-quality evidence to guide the management of RA-ILD, multidisciplinary teams with expertise in RA-ILD are highly valuable for diagnosing and treating RA-ILD. Clinical and translational research in RA-ILD is needed to fill the many evidence gaps.

Treatment of Rheumatoid Arthritis-Associated Interstitial Lung Disease: Lights and Shadows

Rheumatoid arthritis (RA) is a chronic and systemic inflammatory disease affecting 0.5–1% of the population worldwide. Interstitial lung disease (ILD) is a serious pulmonary complication of RA and it is responsible for 10–20% of mortality, with a mean survival of 5–8 years. However, nowadays there are no therapeutic recommendations for the treatment of RA-ILD. Therapeutic options for RA-ILD are complicated by the possible pulmonary toxicity of many disease modifying anti-rheumatic drugs (DMARDs) and by their unclear efficacy on pulmonary disease. Therefore, joint and lung involvement should be evaluated independently of each other for treatment purposes. On the other hand, some similarities between RA-ILD and idiopathic pulmonary fibrosis and the results of the recent INBIULD trial suggest a possible future role for antifibrotic agents. From this perspective, we review the current literature describing the pulmonary effects of drugs (immunosuppressants, conventional, biological and target synthetic DMARDs and antifibrotic agents) in patients with RA and ILD. In addition, we suggest a framework for the management of RA-ILD patients and outline a research agenda to fill the gaps in knowledge about this challenging patient cohort.