CXCL9, CXCL10, and CXCL11; biomarkers of pulmonary inflammation associated with autoimmunity in patients with collagen vascular diseases-associated interstitial lung disease and interstitial pneumonia with autoimmune features

Clinically Relevant Biomarkers in Connective Tissue Disease-Associated Interstitial Lung Disease

Interstitial lung disease (ILD) complicates connective tissue disease (CTD) with variable incidence and is a leading cause of death in these patients. To improve CTD-ILD outcomes, early recognition and management of ILD is critical. Blood-based and radiologic biomarkers that assist in the diagnosis CTD-ILD have long been studied. Recent studies, including -omic investigations, have also begun to identify biomarkers that may help prognosticate such patients. This review provides an overview of clinically relevant biomarkers in patients with CTD-ILD, highlighting recent advances to assist in the diagnosis and prognostication of CTD-ILD.

Lycopene Regulates Macrophage Immune Response through the Autophagy Pathway Mediated by RIPK1

The effects of lycopene (LP) on macrophage immune responses were evaluated in this study. Compared with the control treatment, LP treatment significantly increased cell vitality, phagocytic activity, and chemokine production in RAW264.7 cells. Additionally, compared with the control treatment, 4 μM LP treatment significantly activated autophagy, enhanced mitochondrial membrane potential, and upregulated receptor-interacting protein kinase 1 (RIPK1), while necrostatin-1 significantly reversed these effects of LP. Furthermore, compared with that in the control group, RIPK1 was significantly upregulated in the 4 μM LP and 4 μM LP + spautin-1 groups, whereas p-mTOR levels were reduced. More importantly, compared with that in the control group, p62 was significantly downregulated, and Beclin1, LC3-II, and Atg7 were upregulated in the 4 μM LP group, while spautin-1 significantly reversed these effects of LP. These results confirm that LP activates the mTOR/Beclin1/LC3/p62 autophagy signaling pathway through RIPK1, thereby enhancing the immune response of macrophages.

High Interleukin-13 level is associated with disease stability in interstitial Lung disease

Purpose

Cytokines can help predict prognosis in interstitial lung disease (ILD) and to differentiate between ILD subtypes. The objectives of our study were to evaluate association of baseline cytokine levels with time to ILD progression and to compare baseline cytokine levels between ILD subtypes.

Methods

We quantified 27 cytokines using a multiplex assay in peripheral blood samples from 77 patients. Cox proportional hazards regression analysis was performed to evaluate cytokine impact on the time to progression in the total cohort and within each ILD type. We evaluated for significant differences in cytokine levels between ILD types using ANOVA, Wilcoxon signed-rank test and Tukey method.

Results

Higher IL-13 level was associated with longer time to progression (hazard ratio 0.52 [0.33-0.81], p-value 0.004). FGF-β, GM-CSF, and IL-17 levels differed significantly between fibrotic and inflammatory ILD subgroups.

Conclusion

IL-13 may be a useful biomarker predicting ILD stability.

MDA5-autoimmunity and interstitial pneumonitis contemporaneous with the COVID-19 pandemic (MIP-C)

BACKGROUND

Anti-MDA5 (Melanoma differentiation-associated protein-5) positive dermatomyositis (MDA5+-DM) is characterised by rapidly progressive interstitial lung disease (ILD) and high mortality. MDA5 is an RNA sensor and a key pattern recognition receptor for the SARS-CoV-2 virus.

METHODS

This is a retrospective observational study of a surge in MDA5 autoimmunity, as determined using a 15 muscle-specific autoantibodies (MSAs) panel, between Janurary 2018 and December 2022 in Yorkshire, UK. MDA5-positivity was correlated with clinical features and outcome, and regional SARS-CoV-2 positivity and vaccination rates. Gene expression patterns in COVID-19 were compared with autoimmune lung disease and idiopathic pulmonary fibrosis (IPF) to gain clues into the genesis of the observed MDA5+-DM outbreak.

FINDINGS

Sixty new anti-MDA5+, but not other MSAs surged between 2020 and 2022, increasing from 0.4% in 2019 to 2.1% (2020), 4.8% (2021) and 1.7% (2022). Few (8/60) had a prior history of confirmed COVID-19, peak rates overlapped with regional SARS-COV-2 community positivity rates in 2021, and 58% (35/60) had received anti-SARS-CoV-2 vaccines. 25/60 cases developed ILD which rapidly progression with death in 8 cases. Among the 35/60 non-ILD cases, 14 had myositis, 17 Raynaud phenomena and 10 had dermatomyositis spectrum rashes. Transcriptomic studies showed strong IFIH1 (gene encoding for MDA5) induction in COVID-19 and autoimmune-ILD, but not IPF, and IFIH1 strongly correlated with an IL-15-centric type-1 interferon response and an activated CD8+ T cell signature that is an immunologic hallmark of progressive ILD in the setting of systemic autoimmune rheumatic diseases. The IFIH1 rs1990760TT variant blunted such response.

INTERPRETATION

A distinct pattern of MDA5-autoimmunity cases surged contemporaneously with circulation of the SARS-COV-2 virus during COVID-19. Bioinformatic insights suggest a shared immunopathology with known autoimmune lung disease mechanisms.

FUNDING

This work was supported in part by the National Institute for Health Research (NIHR) Leeds Biomedical Research Centre (BRC), and in part by the National Institutes of Health (NIH) grant R01-AI155696 and pilot awards from the UC Office of the President (UCOP)-RGPO (R00RG2628, R00RG2642 and R01RG3780) to P.G. S.S was supported in part by R01-AI141630 (to P.G) and in part through funds from the American Association of Immunologists (AAI) Intersect Fellowship Program for Computational Scientists and Immunologists.

Proteomic profiling of bronchoalveolar lavage fluid uncovers protein clusters linked to survival in idiopathic forms of interstitial lung disease

Background

Idiopathic interstitial pneumonias (IIPs) such as idiopathic pulmonary fibrosis (IPF) and interstitial pneumonia with autoimmune features (IPAF), present diagnostic and therapeutic challenges due to their heterogeneous nature. This study aimed to identify intrinsic molecular signatures within the lung microenvironment of these IIPs through proteomic analysis of bronchoalveolar lavage fluid (BALF).

Methods

Patients with IIP (n=23) underwent comprehensive clinical evaluation including pre-treatment bronchoscopy and were compared to controls without lung disease (n=5). Proteomic profiling of BALF was conducted using label-free quantitative methods. Unsupervised cluster analyses identified protein expression profiles which were then analyzed to predict survival outcomes and investigate associated pathways.

Results

Proteomic profiling successfully differentiated IIP from controls. k-means clustering, based on protein expression revealed three distinct IIP clusters, which were not associated with age, smoking history, or baseline pulmonary function. These clusters had unique survival trajectories and provided more accurate survival predictions than the Gender Age Physiology (GAP) index (C-index 0.794 vs. 0.709). The cluster with the worst prognosis featured decreased inflammatory signaling and complement activation, with pathway analysis highlighting altered immune response pathways related to immunoglobulin production and B cell-mediated immunity.

Conclusions

The unsupervised clustering of BALF proteomics provided a novel stratification of IIP patients, with potential implications for prognostic and therapeutic targeting. The identified molecular phenotypes underscore the diversity within the IIP classification and the potential importance of personalized treatments for these conditions. Future validation in larger, multi-ethnic cohorts is essential to confirm these findings and to explore their utility in clinical decision-making for patients with IIP.

Role of serum B-cell-activating factor and interleukin-17 as biomarkers in the classification of interstitial pneumonia with autoimmune features

Interstitial pneumonia with autoimmune features (IPAF) is a type of interstitial lung disease (ILD) with immune features that do not meet the diagnostic criteria for specific connective tissue diseases (CTDs). This retrospective case-control study investigated the role of serum B-cell-activating factor of the tumor necrosis factor family (BAFF) and interleukin (IL)-17 as biomarkers for IPAF. The differences in serum BAFF, IL-17, and IL-10 were compared among patients with idiopathic pulmonary fibrosis (IPF), IPAF, ILD associated with CTD (CTD-ILD), and healthy controls. The patients were treatment naïve. The correlations of BAFF with IL-10, IL-17, and pulmonary function were analyzed. The classifiable value of BAFF for IPAF was examined. The results showed that the serum levels of BAFF and IL-17 in the IPAF and CTD-ILD groups were higher than in the IPF group. High BAFF levels and high predicted diffusion capacity of the lungs for carbon monoxide (DLCO) were independent predictive factors for IPAF vs IPF. In the IPAF and CTD-ILD groups, serum BAFF levels were negatively correlated with predicted values of forced vital capacity (FVC%) and diffusing capacity of the lungs for carbon monoxide (DLCO%) and positively correlated with serum IL-17 and IL-10 levels. The cutoff value of combined BAFF and IL-17 was 0.704, and the sensitivity and specificity for classifying IPAF were 78.9 and 95.7%, respectively. In conclusion, combining serum BAFF and IL-17 as a biomarker may have classifiable value in differentiating IPAF from other forms of ILD.

CCL18, CHI3L1, ANG2, IL-6 systemic levels are associated with the extent of lung damage and radiomic features in SARS-CoV-2 infection

OBJECTIVE AND DESIGN

We aimed to identify cytokines whose concentrations are related to lung damage, radiomic features, and clinical outcomes in COVID-19 patients.

MATERIAL OR SUBJECTS

Two hundred twenty-six patients with SARS-CoV-2 infection and chest computed tomography (CT) images were enrolled.

METHODS

CCL18, CHI3L1/YKL-40, GAL3, ANG2, IP-10, IL-10, TNFα, IL-6, soluble gp130, soluble IL-6R were quantified in plasma samples using Luminex assays. The Mann-Whitney U test, the Kruskal-Wallis test, correlation and regression analyses were performed. Mediation analyses were used to investigate the possible causal relationships between cytokines, lung damage, and outcomes. AVIEW lung cancer screening software, pyradiomics, and XGBoost classifier were used for radiomic feature analyses.

RESULTS

CCL18, CHI3L1, and ANG2 systemic levels mainly reflected the extent of lung injury. Increased levels of every cytokine, but particularly of IL-6, were associated with the three outcomes: hospitalization, mechanical ventilation, and death. Soluble IL-6R showed a slight protective effect on death. The effect of age on COVID-19 outcomes was partially mediated by cytokine levels, while CT scores considerably mediated the effect of cytokine levels on outcomes. Radiomic-feature-based models confirmed the association between lung imaging characteristics and CCL18 and CHI3L1.

CONCLUSION

Data suggest a causal link between cytokines (risk factor), lung damage (mediator), and COVID-19 outcomes.

CXCL10 as a biomarker of interstitial lung disease in patients with rheumatoid arthritis

INTRODUCTION

Pulmonary involvement is a frequent and serious rheumatoid arthritis (RA) manifestation that affects 60%-80% of patients. CXCL10 is an inflammatory chemokine that regulates different biological responses, such as chemotaxis, angiogenesis, and inflammation.

AIM

This study aimed to identify the role of CXCL10 as a peripheral blood marker of RA-ILD and its correlation with disease activity.

PATIENTS AND METHODS

This cross-sectional study included 73 patients with RA (33 with ILD and 40 without ILD). Pulmonary function tests and high-resolution computed tomography were performed. Blood samples were taken for complete blood count and blood chemistry analysis, and human interferon-inducible protein 10 (IP-10/CXCL10) level. Statistical Package for the Social Sciences (version 22) was used for all statistical calculations.

RESULTS

The serum CXCL10 level and patient age (r=.393, p=.024), disease duration (r=.756, p<0.001), erythrocyte sedimentation rate (r=.516, p=.002), C-reactive protein (r=.539, p=.001), and rheumatoid factor (r=.663, p<.001) revealed a significant positive correlation. Furthermore, the Modified Health Assessment Questionnaire (r=-.418, p=.015) revealed a significant negative correlation. Patients with RA-ILD show significantly higher CXCL10 than those without ILD (p<.001).

CONCLUSION

CXCL10 is a useful RA disease activity biomarker and is an RA-ILD-sensitive biomarker, also CXCL10 is a significant predictor for development of RA-ILD.

High serum C-X-C motif chemokine ligand 10 (CXCL10) levels may be associated with new onset interstitial lung disease in patients with systemic sclerosis: evidence from observational, clinical, transcriptomic and in vitro studies

BACKGROUND

Systemic sclerosis-interstitial lung disease (SSc-ILD) is the leading cause of death in patients with SSc. There is an unmet need for predictive biomarkers to identify patients with SSc at risk of ILD. Previous studies have shown that interferon (IFN) pathways may play a role in SSc. We assessed the use of C-X-C motif chemokine ligand 10 (CXCL10) as a predictive biomarker for new onset of ILD in patients with SSc.

METHODS

One-hundred-sixty-five (Female, N = 130) patients with SSc (SSc-ILD, N = 41) and 13 (Female, N = 8) healthy controls were investigated retrospectively. CXCL10 protein levels were measured by ELISA. We performed log rank analysis with baseline CXCL10 serum levels. CXCL10 nanoString data from lung tissues obtained from transplanted patients with SSc-ILD were extracted. Fifteen (Female, N = 10) patients with SSc (SSc-ILD, N = 7) were recruited for bronchoalveolar lavage (BAL) procedure. Lung fibroblasts were treated with BAL-fluid or serum from patients with SSc with or without ILD. Inflammatory/fibrotic genes were assessed.

FINDINGS

Serum CXCL10 levels were higher in patients with SSc-ILD compared to SSc patients without ILD [Median (IQR):126 pg/ml (66-282.5) vs. 78.5 pg/ml (50-122), P = 0.029, 95% CI: 1.5 × 10-6 to 0.4284]. Survival analysis showed that baseline CXCL10 levels >78.5 pg/ml have a 2.74-fold increased risk of developing new onset of ILD (Log-rank: P = 0.119) on follow-up. CXCL10 levels in BAL supernatant were not different in patients with SSc-ILD compared to SSc without ILD [76.1 pg/ml (7.2-120.8) vs. 22.3 pg/ml (12.1-43.7), P = 0.24, 95% CI: -19.5 to 100]. NanoString showed that CXCL10 mRNA expression was higher in inflammatory compared to fibrotic lung tissues [4.7 (4.2-5.6) vs. 4.3 (3.6-4.7), P = 0.029]. Fibroblasts treated with SSc-ILD serum or BAL fluids overexpressed CXCL10.

INTERPRETATIONS

Clinical, transcriptomic, and in vitro data showed that CXCL10 is potentially involved in early SSc-ILD. More research is needed to confirm whether CXCL10 can be classified as a prospective biomarker to detect patients with SSc at higher risk of developing new onset ILD.

FUNDING

This collaborative project is co-financed by the Ministry of Economic Affairs and Climate Policy of the Netherlands utilizing the PPP-allowance made available by the Top Sector Life Sciences & Health to stimulate public-private partnerships (PPP-2019_007). Part of this study is financially supported by Sanofi Genzyme (NL8921).

Study on Potential Differentially Expressed Genes in Idiopathic Pulmonary Fibrosis by Bioinformatics and Next-Generation Sequencing Data Analysis

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease with reduced quality of life and earlier mortality, but its pathogenesis and key genes are still unclear. In this investigation, bioinformatics was used to deeply analyze the pathogenesis of IPF and related key genes, so as to investigate the potential molecular pathogenesis of IPF and provide guidance for clinical treatment. Next-generation sequencing dataset GSE213001 was obtained from Gene Expression Omnibus (GEO), and the differentially expressed genes (DEGs) were identified between IPF and normal control group. The DEGs between IPF and normal control group were screened with the DESeq2 package of R language. The Gene Ontology (GO) and REACTOME pathway enrichment analyses of the DEGs were performed. Using the g:Profiler, the function and pathway enrichment analyses of DEGs were performed. Then, a protein-protein interaction (PPI) network was constructed via the Integrated Interactions Database (IID) database. Cytoscape with Network Analyzer was used to identify the hub genes. miRNet and NetworkAnalyst databaseswereused to construct the targeted microRNAs (miRNAs), transcription factors (TFs), and small drug molecules. Finally, receiver operating characteristic (ROC) curve analysis was used to validate the hub genes. A total of 958 DEGs were screened out in this study, including 479 up regulated genes and 479 down regulated genes. Most of the DEGs were significantly enriched in response to stimulus, GPCR ligand binding, microtubule-based process, and defective GALNT3 causes HFTC. In combination with the results of the PPI network, miRNA-hub gene regulatory network and TF-hub gene regulatory network, hub genes including LRRK2, BMI1, EBP, MNDA, KBTBD7, KRT15, OTX1, TEKT4, SPAG8, and EFHC2 were selected. Cyclothiazide and rotigotinethe are predicted small drug molecules for IPF treatment. Our findings will contribute to identification of potential biomarkers and novel strategies for the treatment of IPF, and provide a novel strategy for clinical therapy.

MDA5-autoimmunity and Interstitial Pneumonitis Contemporaneous with the COVID-19 Pandemic (MIP-C)

Background

Anti-MDA5 (Melanoma differentiation-associated protein-5) positive dermatomyositis (MDA5 + -DM) is characterised by rapidly progressive interstitial lung disease (ILD) and high mortality. MDA5 senses single-stranded RNA and is a key pattern recognition receptor for the SARS-CoV-2 virus.

Methods

This is a retrospective observational study of a surge in MDA5 autoimmunity, as determined using a 15 muscle-specific autoantibodies (MSAs) panel, between Janurary 2018-December 2022 in Yorkshire, UK. MDA5-positivity was correlated with clinical features and outcome, and regional SARS-CoV-2 positivity and vaccination rates. Gene expression patterns in COVID-19 were compared with autoimmune lung disease and idiopathic pulmonary fibrosis (IPF) to gain clues into the genesis of the observed MDA5 + -DM outbreak.

Results

Sixty new anti-MDA5+, but not other MSAs surged between 2020-2022, increasing from 0.4% in 2019 to 2.1% (2020), 4.8% (2021) and 1.7% (2022). Few (8/60) had a prior history of confirmed COVID-19, peak rates overlapped with regional SARS-COV-2 community positivity rates in 2021, and 58% (35/60) had received anti-SARS-CoV-2 RNA vaccines. Few (8/60) had a prior history of COVID-19, whereas 58% (35/60) had received anti-SARS-CoV-2 RNA vaccines. 25/60 cases developed ILD which rapidly progression with death in 8 cases. Among the 35/60 non-ILD cases, 14 had myositis, 17 Raynaud phenomena and 10 had dermatomyositis spectrum rashes. Transcriptomic studies showed strong IFIH1 (gene encoding for MDA5) induction in COVID-19 and autoimmune-ILD, but not IPF, and IFIH1 strongly correlated with an IL-15-centric type-1 interferon response and an activated CD8+ T cell signature that is an immunologic hallmark of progressive ILD in the setting of systemic autoimmune rheumatic diseases. The IFIH1 rs1990760TT variant blunted such response.

Conclusions

A distinct pattern of MDA5-autoimmunity cases surged contemporaneously with circulation of the SARS-COV-2 virus during COVID-19. Bioinformatic insights suggest a shared immunopathology with known autoimmune lung disease mechanisms.

Survival and soluble immune mediators of immune checkpoint inhibitor-induced interstitial lung disease in patients with non-small cell lung cancer

BACKGROUND

Immune checkpoint inhibitor-related interstitial lung disease (ICI-ILD) is a serious adverse event frequently observed in patients with non-small cell lung cancer (NSCLC). We investigated the clinical effects and mechanism of action of ICI-ILD in NSCLC patients treated with ICI.

METHODS

We retrospectively screened patients with advanced or recurrent NSCLC who received PD-1/PD-L1 inhibitor monotherapy and examined the prognostic impact of ICI-ILD. In addition, we analyzed the levels of 72 different soluble immune mediators in pre-treatment plasma to explore possible mechanisms associated with the development of ICI-ILD. Furthermore, the relationships between soluble immune mediators associated with ICI-ILD development and survival were analyzed.

RESULTS

Of 141 patients with NSCLC, 25 (17.7%) developed ICI-ILD. Logistic regression analysis revealed that pre-treatment CXCL9, MMP-1, IL-6, and IL-19 levels were associated with ICI-ILD development. There were no significant differences in progression-free survival (PFS) and overall survival (OS) between patients with or without ICI-ILD. In patients with ICI-ILD, patients with lower grade ICI-ILD had better OS than those with higher-grade ICI-ILD. In ICI-ILD patients, there was a trend for patients with lower-grade ICI-ILD to have better PFS and OS than those with higher-grade ICI-ILD. Among four soluble immune mediators associated with ICI-ILD, a high level of IL-19 was significantly correlated with worse OS and PFS.

CONCLUSION

The identified soluble immune mediators, including CXCL9, MMP-1, IL-6, and IL-19, may be useful as biomarkers to associate with ICI-ILD development. Although we did not detect significant differences in PFS and OS between patients with and without ICI-ILD, PFS and OS were longer in those with lower-grade ICI-ILD than in patients with higher-grade ICI-ILD. Among biomarkers, IL-19 may be a causal and prognostic factor for ICI-ILD.

Discovering the Protective Effects of Quercetin on Aflatoxin B1-Induced Toxicity in Bovine Foetal Hepatocyte-Derived Cells (BFH12)

Aflatoxin B1 (AFB1) induces lipid peroxidation and mortality in bovine foetal hepatocyte-derived cells (BFH12), with underlying transcriptional perturbations associated mainly with cancer, cellular damage, inflammation, bioactivation, and detoxification pathways. In this cell line, curcumin and resveratrol have proven to be effective in mitigating AFB1-induced toxicity. In this paper, we preliminarily assessed the potential anti-AFB1 activity of a natural polyphenol, quercetin (QUE), in BFH12 cells. To this end, we primarily measured QUE cytotoxicity using a WST-1 reagent. Then, we pre-treated the cells with QUE and exposed them to AFB1. The protective role of QUE was evaluated by measuring cytotoxicity, transcriptional changes (RNA-sequencing), lipid peroxidation (malondialdehyde production), and targeted post-transcriptional modifications (NQO1 and CYP3A enzymatic activity). The results demonstrated that QUE, like curcumin and resveratrol, reduced AFB1-induced cytotoxicity and lipid peroxidation and caused larger transcriptional variations than AFB1 alone. Most of the differentially expressed genes were involved in lipid homeostasis, inflammatory and immune processes, and carcinogenesis. As for enzymatic activities, QUE significantly reverted CYP3A variations induced by AFB1, but not those of NQO1. This study provides new knowledge about key molecular mechanisms involved in QUE-mediated protection against AFB1 toxicity and encourages in vivo studies to assess QUE's bioavailability and beneficial effects on aflatoxicosis.

Distribution and chemotactic mechanism of CD4+ T cells in traumatic tracheal stenosis

A systemic and local inflammatory immune imbalance is thought to be the cause of traumatic tracheal stenosis (TS). However, with CD4+ T lymphocytes being the predominant immune cells in TS, the mechanism of action and recruitment has not been described. In our research, using flow cytometry, ELISA, immunofluorescence, and Transwell chamber assays, the expression, distribution, and potential chemotactic function of CD4+ T cells in TS patients were examined before and after treatment. The results showed that the untreated group had significantly more CD4+ T cells and their secreted TGF-β1 than the treated group. Additionally, the untreated group's CD4+ T cells showed a significant rise in CCL22 and CCL1, as well as a larger proportion of CCR4 and CCR8. CD4+ T cells and CD68+ macrophages located in TS also expressed CCL1 and CCL22. In vitro, anti-CCL1 and anti-CCL22 can partially block the chemoattractant effect of TS bronchoalveolar lavage (BAL) on purified CD4+ T cells. The findings of this study indicated that TS contained unbalanced CD4 immune cells that were actively recruited locally by CCR4/CCL22 and CCR8/CCL1. As a result, it is anticipated that CD4 immune rebalancing can serve as a novel treatment for TS.

Role of miR-15a-5p and miR-199a-3p in the inflammatory pathway regulated by NF-κB in experimental and human atherosclerosis

BACKGROUND

Cardiovascular diseases (CVDs) prevalence has significantly increased in the last decade and atherosclerosis development is the main trigger. MicroRNAs (miRNAs) are non-coding RNAs that negatively regulate gene expression of their target and their levels are frequently altered in CVDs.

METHODS

By RT-qPCR, we analysed miR-9-5p, miR-15a-5p, miR-16-5p and miR-199a-3p levels in aorta from apolipoprotein knockout (ApoE-/- ) mice, an experimental model of hyperlipidemia-induced atherosclerosis, and in human aortic and carotid atherosclerotic samples. By in silico studies, Western blot analysis and immunofluorescence studies, we detected the targets of the altered miRNAs.

RESULTS

Our results show that miR-15a-5p and miR-199a-3p are significantly decreased in carotid and aortic samples from patients and mice with atherosclerosis. In addition, we found an increased expression in targets of both miRNAs that participate in the inflammatory pathway of nuclear factor kappa B (NF-κB), such as IKKα, IKKβ and p65. In human vein endothelial cells (HUVECs) and vascular smooth muscle cells (VSMCs), the overexpression of miR-15a-5p or miR-199a-3p decreased IKKα, IKKβ and p65 protein levels as well as NF-κB activation. On the other hand, miR-15a-5p and miR-199a-3p overexpression reduced ox-LDL uptake and the inflammation regulated by NF-κB in VSMCs. Moreover, although miR-15a-5p and miR-199a-3p were significantly increased in exosomes from patients with advanced carotid atherosclerosis, only in the ROC analyses for miR-15a-5p, the area under the curve was 0.8951 with a p value of .0028.

CONCLUSIONS

Our results suggest that the decrease of miR-199a-3p and miR-15a-5p in vascular samples from human and experimental atherosclerosis could be involved in the NF-κB activation pathway, as well as in ox-LDL uptake by VSMCs, contributing to inflammation and progression atherosclerosis. Finally, miR-15a-5p could be used as a novel diagnostic biomarker for advanced atherosclerosis.

Clinically Relevant Biomarkers in Connective Tissue Disease-Associated Interstitial Lung Disease

Interstitial lung disease (ILD) complicates connective tissue disease (CTD) with variable incidence and is a leading cause of death in these patients. To improve CTD-ILD outcomes, early recognition and management of ILD is critical. Blood-based and radiologic biomarkers that assist in the diagnosis CTD-ILD have long been studied. Recent studies, including -omic investigations, have also begun to identify biomarkers that may help prognosticate such patients. This review provides an overview of clinically relevant biomarkers in patients with CTD-ILD, highlighting recent advances to assist in the diagnosis and prognostication of CTD-ILD.

Development of a new HISCL automated CXCL9 immunoassay

C-X-C motif chemokine ligand 9 (CXCL9), a candidate biomarker, reflects type 1 (T1) inflammation pathology. Here, we report the analytical performance and clinical characteristics of a new CXCL9 reagent for a fully automated immunoassay device. We evaluated the limits of blank, detection, and quantitation (LoQ) along with other efficacy parameters, and the ability of the assay to report patient health, COVID-19 status, and the presence of asthma and/or interstitial lung diseases (ILDs). The coefficient of variation for 5-day total precision using two instruments was 7% across two controls, serum, and plasma panels. LoQ of 2.2 pg/mL suggested the efficacy of the assay in detecting T1 inflammation in plasma or serum; no cross-reactivity or interference was observed. We identified high serum CXCL9 levels in samples from patients with acute COVID-19 infections (n = 57), chronic bird-related hypersensitivity pneumonitis (n = 61), asthma (n = 194), and ILDs (n = 84) compared to healthy individuals (< 39.0 pg/mL). Furthermore, CXCL9 levels increased with age in asthma patients, and an opposite trend was observed for T2 inflammatory factors. These results suggest the utility of the automated CXCL9 immunoassay for measuring CXCL9 in clinical samples and reflect its role in T1 inflammation.

Human Metapneumovirus (hMPV) Infection and MPV467 Treatment in Immunocompromised Cotton Rats Sigmodon hispidus

Human metapneumovirus (hMPV) is an important cause of respiratory disease in immunocompromised individuals, yet hMPV infection has not been modeled before in immunocompromised animals. In this work, cotton rats S. hispidus immunosuppressed by cyclophosphamide were infected with hMPV, and viral replication and pulmonary inflammation in these animals were compared to those in normal hMPV-infected S. hispidus. The efficacy of prophylactic and therapeutic administration of the anti-hMPV antibody MPV467 was also evaluated. Immunosuppressed animals had higher pulmonary and nasal titers of hMPV on day 5 post-infection compared to normal animals, and large amounts of hMPV were still present in the respiratory tract of immunosuppressed animals on days 7 and 9 post-infection, indicating prolonged viral replication. Immunosuppression was accompanied by reduced pulmonary histopathology in hMPV-infected cotton rats compared to normal animals; however, a delayed increase in pathology and pulmonary chemokine expression was seen in immunosuppressed cotton rats. Prophylactic and therapeutic MPV467 treatments protected both upper and lower respiratory tracts against hMPV infection. The lung pathology and pulmonary expression of IP-10 and MIP-1α mRNA were reduced by therapeutic MPV467 administration. These results indicate that immunosuppressed cotton rats represent a useful model for studying hMPV pathogenesis and for evaluating therapeutics that could alleviate hMPV-induced disease in immunocompromised subjects.

One Hundred Consecutive Neutropenic Febrile Episodes Demonstrate That CXCR3 Ligands Have Predictive Value in Discriminating the Severity of Infection in Children with Cancer

This study assesses the value of the CXCR3 ligands CXCL9/MIG, CXCL10/IP-10 and CXCL11/I-TAC when used to supplement the standard infection markers C-reactive protein (CRP) and procalcitonin (PCT) in the diagnostic algorithm of neutropenic fever in children with cancer. The concentration of CRP, PCT and chemokines was determined during the first hour of fever and 12-24 h afterwards in pediatric oncology patients with neutropenia. Among 100 consecutive febrile episodes in neutropenic patients, 34 cases demonstrated fever of unknown origin (FUO) (group A), 47 demonstrated mild clinically or microbiologically proven infection (Group B) and 19 severe infection (Group C). Significantly higher PCT-1 levels were found in group C (0.24 ng/mL) vs. group A (0.16 ng/mL), and PCT-2 in group C (1.2 ng/mL) vs. A (0.17 ng/mL), and in C vs. B (0.2 ng/mL). Chemokine concentrations (I-TAC-1, IP-10-1, IP-10-2) were significantly lower in Group A vs. B+C; I-TAC 1: 48.64 vs. 70.99 pg/mL, p = 0.03; IP-10 1: 59.95 vs. 96.84 pg/mL, p = 0.04; and IP-10 2: 102.40 vs. 149.39 pg/mL, p = 0.05. The selected pro-inflammatory chemokines I-TAC and IP10 might help to distinguish cancer patients with febrile neutropenia with the highest risk of infection. Although procalcitonin could serve as a marker of a high risk of infection, its delayed response diminishes its usefulness.

Interstitial Pneumonia with Autoimmune Features: What the Rheumatologist Needs to Know

PURPOSE OF REVIEW

This narrative review will focus on the role of the rheumatologist in evaluating patients with interstitial lung disease (ILD) without a defined rheumatic disease and will outline the current classification criteria for interstitial pneumonia with autoimmune features (IPAF) and describe what is known regarding IPAF pathobiology, natural history, prognosis, and treatment. Lastly, knowledge gaps and opportunities for future research will be discussed.

RECENT FINDINGS

IPAF is a recently defined classification of ILD patients who have features suggesting an autoimmune-mediated process, but do not fulfill current rheumatic disease criteria. The goal of the IPAF criteria is to provide a uniform case definition for the study of autoimmune ILD patients who do not currently fit within standard ILD diagnostic categories, ultimately improving diagnosis and therapy. Many of these patients are referred for rheumatologic evaluation to aid the diagnostic process. The care of the IPAF patient is complex and is multidisciplinary with pulmonology, rheumatology, pathology, radiology, physical therapy, primary care, pulmonary transplant providers all serving vital roles. The rheumatologist has several roles which include classification, disease monitoring, and management.

The Ameliorative Effect of Dexamethasone on the Development of Autoimmune Lung Injury and Mediastinal Fat-Associated Lymphoid Clusters in an Autoimmune Disease Mouse Model

In our previous study, we revealed the ameliorative therapeutic effect of dexamethasone (Dex) for Lupus nephritis lesions in the MRL/MpJ-Fas ^lpr/lpr (Lpr) mouse model. The female Lpr mice developed a greater number of mediastinal fat-associated lymphoid clusters (MFALCs) and inflammatory lung lesions compared to the male mice. However, the effect of Dex, an immunosuppressive drug, on both lung lesions and the development of MFALCs in Lpr mice has not been identified yet. Therefore, in this study, we compared the development of lung lesions and MFALCs in female Lpr mice that received either saline (saline group “SG”) or dexamethasone (dexamethasone group “DG”) in drinking water as a daily dose along with weekly intraperitoneal injections for 10 weeks. Compared to the SG group, the DG group showed a significant reduction in the levels of serum anti-dsDNA antibodies, the size of MFALCs, the degree of lung injury, the area of high endothelial venules (HEVs), and the number of proliferating and immune cells in both MFALCs and the lungs. A significant positive correlation was observed between the size of MFALCs and the cellular aggregation in the lungs of Lpr mice. Therefore, this study confirmed the ameliorative effect of Dex on the development of lung injury and MFALCs via their regressive effect on both immune cells’ proliferative activity and the development of HEVs. Furthermore, the reprogramming of MFALCs by targeting immune cells and HEVs may provide a therapeutic strategy for autoimmune-disease-associated lung injury.

Inflammatory marker trajectories associated with frailty and ageing in a 20‐year longitudinal study

Objective

The aim of this exploratory study was to investigate the development of low‐grade inflammation during ageing and its relationship with frailty.

Methods

The trajectories of 18 inflammatory markers measured in blood samples, collected at 5‐year intervals over a period of 20 years from 144 individuals aged 65–75 years at the study endpoint, were related to the degree of frailty later in life.

Results

IFN‐γ‐related markers and platelet activation markers were found to change in synchrony. Chronically elevated levels of IL‐6 pathway markers, such as CRP and sIL‐6R, were associated with more frailty, poorer lung function and reduced physical strength. Being overweight was a possible driver of these associations. More and stronger associations were detected in women, such as a relation between increasing sCD14 levels and frailty, indicating a possible role for monocyte overactivation. Multivariate prediction of frailty confirmed the main results, but predictive accuracy was low.

Conclusion

In summary, we documented temporal changes in and between inflammatory markers in an ageing population over a period of 20 years, and related these to clinically relevant health outcomes.

Platelets and Antiplatelet Medication in COVID-19-Related Thrombotic Complications

Coronavirus disease 2019 (COVID-19) induces a hypercoagulatory state that frequently leads to thromboembolic complications. Whereas anticoagulation is associated with reduced mortality, the role of antiplatelet therapy in COVID-19 is less clear. We retrospectively analyzed the effect of anticoagulation and antiplatelet therapy in 578 hospitalized patients with COVID-19 and prospectively monitored 110 patients for circulating microthrombi and plasma markers of coagulation in the first week of admission. Moreover, we determined platelet shape change and also thrombi in postmortem lung biopsies in a subset of patients with COVID-19. We observed no association of antiplatelet therapy with COVID-19 survival. Adverse outcome in COVID-19 was associated with increased activation of the coagulation cascade, whereas circulating microthrombi did not increase in aggravated disease. This was in line with analysis of postmortem lung biopsies of patients with COVID-19, which revealed generally fibrin(ogen)-rich and platelet-low thrombi. Platelet spreading was normal in severe COVID-19 cases; however, plasma from patients with COVID-19 mediated an outcome-dependent inhibitory effect on naïve platelets. Antiplatelet medication disproportionally exacerbated this platelet impairment in plasma of patients with fatal outcome. Taken together, this study shows that unfavorable outcome in COVID-19 is associated with a profound dysregulation of the coagulation system, whereas the contribution of platelets to thrombotic complications is less clear. Adverse outcome may be associated with impaired platelet function or platelet exhaustion. In line, antiplatelet therapy was not associated with beneficial outcome.

Review: Serum Biomarkers of Lung Fibrosis in Interstitial Pneumonia with Autoimmune Features-What Do We Already Know?

Interstitial pneumonia with autoimmune features (IPAF) belongs to a group of diseases called interstitial lung diseases (ILDs), which are disorders of a varied prognosis and course. Finding sufficiently specific and sensitive biomarkers would enable the progression to be predicted, the natural history to be monitored and patients to be stratified according to their treatment. To assess the significance of pulmonary fibrosis biomarkers studied thus far, we searched the PubMed, Medline and Cochrane Library databases for papers published between January 2015 and June 2021. We focused on circulating biomarkers. A primary review of the databases identified 38 articles of potential interest. Overall, seven articles fulfilled the inclusion criteria. This review aims to assess the diagnostic and prognostic value of molecules such as KL-6, SP-A, SP-D, circulating fibrocytes, CCL2, CXCL13, CXCL9, CXCL10 and CXCL11. All of these biomarkers have previously been studied in idiopathic pulmonary fibrosis (IPF) and connective tissue disease-associated interstitial lung disease (CTD-ILD). IPAF is a disorder of a heterogeneous nature. It explains the lack of coherent observations in terms of correlations with functional parameters. There is still no meta-analysis of pulmonary fibrosis biomarkers in IPAF. This is mainly due to the heterogeneity of the methodology and groups analysed in the research. More research in this area is needed.

Natural history and screening of interstitial lung disease in systemic autoimmune rheumatic disorders

Interstitial lung disease (ILD) is a relatively frequent manifestation of systemic autoimmune rheumatic disorders (SARDs), including systemic sclerosis (SSc), rheumatoid arthritis (RA), idiopathic inflammatory myopathies (IIM), systemic lupus erythematosus (SLE), primary Sjögren's syndrome (pSS), and anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis. Interstitial pneumonia with autoimmune features (IPAF) has been proposed to describe patients with ILD who have clinical or serological findings compatible with SARDs but they are not sufficient for a definite diagnosis. ILD may present with different patterns among patients with SARDs, but most commonly as nonspecific interstitial pneumonia (NSIP), with the exception of RA and ANCA vasculitis that more often present with usual interstitial pneumonia (UIP). The natural history of ILD is quite variable, even among patients with the same SARD. It may present with subclinical features following a slow progressively course or with acute manifestations and clinically significant rapid progression leading to severe deterioration of pulmonary function and respiratory failure. The radiographic pattern of ILD, the extent of the disease, the baseline pulmonary function, the pulmonary function deterioration rate over time and clinical variables related to the primary SARD, such as age, sex and the clinical phenotype, are considered prognostic factors for SARDs-ILD associated with adverse outcomes and increased mortality. Different modalities can be employed for ILD detection including clinical evaluation, pulmonary function tests, high resolution computed tomography and novel techniques such as lung ultrasound and serum biomarkers. ILD may determine the clinical outcome of SARDs, since it is associated with significant morbidity and mortality and therefore screening of patients with SARDs for ILD is of great clinical importance.

Serum TARC Levels in Patients with Systemic Sclerosis: Clinical Association with Interstitial Lung Disease

Systemic sclerosis (SSc) is a multisystem fibrotic disorder with autoimmune background. Accumulating evidence has highlighted the importance of T helper (Th) 2 cells in the pathogenesis of SSc and its complications. Because thymus and activation-regulated chemokine (TARC) is a potent chemoattractant for Th2 cells, we measured serum TARC levels in SSc patients and analyzed their correlation with interstitial lung disease (ILD), a major complication of SSc. Serum TARC levels were significantly elevated in patients with SSc, especially in those with the diffuse subtype, compared with healthy controls. In particular, dcSSc patients with SSc-associated ILD (SSc-ILD) showed higher TARC levels than those without SSc-ILD. However, there was no significant correlation between serum TARC levels and pulmonary function in SSc patients. Serum TARC levels did not correlate with serum levels of interleukin-13, an important Th2 cytokine, either. Furthermore, in the longitudinal study, serum TARC levels did not predict the onset or progression of SSc-ILD in patients with SSc. These results were in contrast with those of KL-6 and surfactant protein D, which correlated well with the onset, severity, and progression of SSc-ILD. Overall, these results suggest that serum TARC levels are not suitable for monitoring the disease activity of SSc-ILD.