Severe Interstitial Lung Disease Research Articles

Rheumatoid arthritis disease activity significantly impacts on the severity of interstitial lung disease

ObjectivesRheumatoid arthritis (RA) related interstitial lung disease (ILD) impacts on the treatment strategy and its prognosis in patients with RA. However, the relationship between RA disease activity and the severity of comorbid ILD has not been fully investigated. This study aimed to investigate the impact of RA disease activity on the severity of comorbid ILD in detail based on currently established visual scoring method along with physiological severity.MethodsConsecutive patients with RA visiting to our Rheumatology Centre between December 2020 and December 2023 were analysed. The radiological severity of ILD was evaluated by averaging the extent of the combined lesion of ground glass opacity, reticulation and honeycombing in 5% increments in six representative high-resolution computed tomography slices ranging from 0% (no involvement) to 100% (all lung fields affected) according to Goh and Walsh’s method. Associations between the radiological and physiological severity of ILD and patients’ features were investigated using linear regression analysis.ResultsAmong 124 patients (32 men, 92 women), the median age was 70 years, and the median disease duration was 2.92 years. Radiological severity of ILD was 0% (without ILD) in 107 (86.2%), ILD with extent < 10% in nine (7.2%), ILD with extent ≥10% and < 20% in three (2.4%), ILD with extent ≥20% in five (4.0%). Both disease activity score (DAS)28-erythrocyte sedimentation rate (ESR) (standardized coefficient = 0.199, P = 0.03) and rheumatoid factor titre (standardized coefficient = 0.247, P = 0.01) were significantly associated with the radiological quantitative severity of ILD in multivariate analysis adjusted for age, sex, disease duration, smoking status and anti-citrullinated peptide antibody titre. DAS28-ESR was significantly associated with forced vital capacity% predicted (standardized coefficient = -0.230, P = 0.047).ConclusionsDisease activity of RA was significantly associated with the severity of RA-ILD both radiologically and physiologically.

A PD-1highCD4+ T Cell Population With a Cytotoxic Phenotype is Associated With Interstitial Lung Disease in Systemic Sclerosis.

T cells contribute to tissue injury in systemic sclerosis (SSc), yet the specific T cell subsets expanded in patients with SSc remain incompletely defined. Here we evaluated specific phenotypes and functions of peripheral helper T (Tph) and follicular helper T (Tfh) cells, which have been implicated in autoantibody production, and assessed their associations with clinical features in a well-characterized cohort of patients with SSc. Mass cytometry of T cells from peripheral blood mononuclear cells of patients with SSc and controls were evaluated using t-distributed stochastic neighbor embedding visualization, biaxial gating, and marker expression levels. Findings were validated with flow cytometry and in vitro assays. The frequencies of PD-1highCXCR5+ Tfh cells and PD-1highCXCR5- Tph cells were similar in patients with SSc and controls. t-distributed stochastic neighbor embedding visualization (tSNE) revealed distinct populations within the PD-1highCXCR5- cells distinguished by expression of HLA-DR and inducible costimulator (ICOS). Among PD-1highCXCR5- cells, only the HLA-DR+ICOS- cell population was expanded in patients with SSc. Cytometric and RNA sequencing analyses indicated that these cells expressed cytotoxic rather than B cell helper features. HLA-DR+ICOS- PD-1highCXCR5- cells were less potent in inducing B cell plasmablast differentiation and antibody production than comparator T helper cell populations. HLA-DR+ICOS-PD-1highCXCR5- cells were significantly associated with the presence and severity of interstitial lung disease among patients with SSc. Among PD-1highCXCR5- T cells, a subset of HLA-DR+ICOS- cells with cytotoxic features is specifically expanded in patients with SSc and is significantly associated with interstitial lung disease severity. This potential cytotoxicity appearing in the CD4 T cell population can be evaluated as a prognostic disease biomarker in patients with SSc.

P149 Association between nailfold videocapillaroscopy findings and sKL-6 levels in patients with idiopathic inflammatory myopathies-related interstitial lung disease

Abstract Background/Aims Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of acquired muscle diseases with distinct clinical, pathological and histological features. Interstitial lung disease (ILD) is a frequent pulmonary manifestation in IIM (IIM-ILD) and considerably influences morbidity and mortality. Krebs von den Lungen 6 (sKL-6) has been proposed as a potential biomarker reflecting the severity of ILD in connective tissue diseases. Raynaud’s phenomenon is very frequent and the presence of microvascular changes in IIM have been described however, the role of nailfold videocapillaroscopy (NVC) in diagnosis and prognosis in IIM is not clearly established. We aim to determine if there is any association between NVC findings, sKL-6 levels and pulmonary involvement in patients with inflammatory myopathies. Methods We performed a retrospective study of IIM patients followed in a reference center and compared them according to the presence of ILD. Epidemiological, clinical and immunological data, pulmonary function tests (forced vital capacity and diffusing capacity for carbon monoxide), sKL-6 levels and NVC finding were retrieved. Statistical analysis was performed by T-test and Fisher’s exact test to compare qualitative and/or quantitative variables and multiple logistic regression modelling to identify correlation between pulmonary function tests, NVC findings and sKL-6 levels. Results 95 patients were included, 47 patients (49%) with ILD. 34% were male with a median age at inclusion of 55.3±24 years. Avascular areas and capillary lossshowed a significant association with the presence of ILD (OR 2.43, 95% CI 1.3-5.7, p 0.004) and (OR 1.7, 95% CI 1.48-3.1, p 0.04). A negative correlation between capillary loss and enlarged capillaries was also found with FVC% (β=-0.46, p 0.001 and β=-0.57, p &amp;lt; 0.0001) and DLCO% (β=-0.32, p 0.04 and β=- 0.23, p 0.03), respectively. When we studied the correlation between sKL-6 levels, positive correlations with the presence of ILD (β = 0.77, p 0.0004), the presence of hemorrhages (β = 0.21, p 0.04) and avascular areas in NVC (β = 0.64, p 0.03) and negative correlations with FVC% (β=-0.47, p 0.001) and DLCO% (β=-0.59, p, 0.005) were found. Male sex, respiratory symptoms, %FVC and %DLCO, sKL-6 levels, anti-Jo1 positivity and the presence of avascular areas and enlarged capillaries in NVC were identified as IIM-ILD predictors (R2=0.974, p = 0.006). Conclusion Capillary loss and avascular areas showed a significant association with the presence of ILD, worse FVC and DLCO values and sKL-6 levels. We identified nine predictors for developing ILD in IIM. NVC assessment and sKL-6 levels can have a predictive role for studying pulmonary function and assessing the prognosis of IIM-ILD. Disclosure C. Sieiro Santos: None. J. Tandaipan: None. D. Castillo: None. L. Martínez Martínez: None. H. Codes: None. L. Sainz: None. B. Magallares: None. P. Moya: None. H. Corominas: None. E. Díez Álvarez: None. I. Castellvi: None.

Autoimmunity against melanoma differentiation–associated gene 5 induces interstitial lung disease mimicking dermatomyositis in mice

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive dermatomyositis (DM) is characterized by amyopathic DM with interstitial lung disease (ILD). Patients with anti-MDA5 antibody-associated ILD frequently develop rapidly progression and present high mortality rate in the acute phase. Here, we established a murine model of ILD mediated by autoimmunity against MDA5. Mice immunized with recombinant murine MDA5 whole protein, accompanied with complete Freund's adjuvant once a week for four times, developed MDA5-reactive T cells and anti-MDA5 antibodies. After acute lung injury induced by intranasal administration of polyinosinic-polycytidylic acid [poly (I:C)] mimicking viral infection, the MDA5-immunized mice developed fibrotic ILD representing prolonged respiratory inflammation accompanied by fibrotic changes 2 wk after poly (I:C)-administration, while the control mice had quickly and completely recovered from the respiratory inflammation. Treatment with anti-CD4 depleting antibody, but not anti-CD8 depleting antibody, suppressed the severity of MDA5-induced fibrotic ILD. Upregulation of interleukin (IL)-6 mRNA, which was temporarily observed in poly (I:C)-treated mice, was prolonged in MDA5-immunized mice. Treatment with anti-IL-6 receptor antibody ameliorated the MDA5-induced fibrotic ILD. These results suggested that autoimmunity against MDA5 exacerbates toll-like receptor 3-mediated acute lung injury, and prolongs inflammation resulting in the development of fibrotic ILD. IL-6 may play a key role initiating ILD in this model.

Abstract LB058: N-glycan deglycosylation ameliorates anti-HER2 antibody drug conjugate-induced interstitial pneumonia in preclinical models

Abstract Background: Current clinical application of trastuzumab deruxtecan (T-DXd), an anti-HER2 antibody-drug conjugate (ADC) has been severely limited by interstitial lung disease (ILD). Recent studies suggest a correlation between ILD and the uptake of T-DXd by alveolar macrophages (AMs), which are major innate immune cells in lung tissues. This underlying mechanism of AMs phagocytosing T-DXd was predicted to be the binding interaction between the crystallizable fragment (Fc) of trastuzumab and the Fcγ receptors on the cell surface of AMs, exerting effector functions. Since monoclonal antibodies typically undergo N-glycosylation in the Fc fragment, here we investigate the impacts of antibody N-glycan deglycosylation on T-DXd-induced ILD in preclinical models. Methods: N-glycan removal was performed on trastuzumab and T-DXd using PNGase F. Using immunofluorescence imaging combined with flow cytometry, we conducted a comparative analysis of the binding affinity and internalization efficiency of wild type and fully N-glycan deglycosylated HER2 antibodies. Next, we determined the in vitro cytotoxicity of WT and N-glycan deglycosylated T-DXd against both macrophages and HER2-positive cancer cells using CCK-8 assay. Furthermore, the deposition of N-glycan deglycosylated T-DXd in healthy lungs and their effects in ILD incidence and severity was determined in immunocompetent BALB/c mice carrying HER2-positive tumors. Results: First, we obtained complete N-glycan deglycosylated HER2 antibodies confirmed by SDS-PAGE and mass spectrometry. Next, we showed that N-glycan removal by PNGase F did not affect the Fab fragments of HER2 antibodies binding to the HER2 antigens on HER2-expressing cancer cells (OE19, SK-OV-3 and CT26-hHER2). Importantly, we did observe an approximately 30-50% reduction in the N-glycan deglycosylated HER2 antibodies binding with a panel of three macrophages (MH-S, RAW264.7, and PMA-induced THP-1) in comparison with WT antibodies, indicating a significant impact of N-glycan removal on innate immune cell-mediated effector functions. Moreover, in vitro cytotoxicity studies further support these observations that N-glycan deglycosylated T-DXd has significantly lower cytotoxicities against MH-S (p=0.046) and RAW264.7(p=0.020) in comparison with WT T-DXd. Correlating with our in vitro findings, in vivo biodistribution data showed a reduced lung deposition of HER2 antibodies and T-DXd after N-glycan removal. Immunofluorescence staining confirms the co-localization of HER2 antibodies with CD68-positive macrophages, indicating that AMs are the major contributor to the lung deposition of HER2 antibodies and T-DXd and N-glycan removal could effectively avoid ADC being phagocytosed by AMs. We also demonstrated chronic administration of N-glycan deglycosylated T-DXd could reduce ADC-associated ILD incidence and ameliorate ILD severity. Conclusions: Collectively, our study suggests that antibody N-glycan deglycosylation has important roles in regulating interactions between ADC and innate immune cells. This finding provides valuable clues for further optimizing ADC design and treatment strategies. Citation Format: Yu-Xuan Yang, Le-Tao Ma, Peng Guo. N-glycan deglycosylation ameliorates anti-HER2 antibody drug conjugate-induced interstitial pneumonia in preclinical models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB058.

Severity-stratification of interstitial lung disease by deep learning enabled assessment and quantification of lesion indicators from HRCT images.

Interstitial lung disease (ILD) represents a group of chronic heterogeneous diseases, and current clinical practice in assessment of ILD severity and progression mainly rely on the radiologist-based visual screening, which greatly restricts the accuracy of disease assessment due to the high inter- and intra-subjective observer variability. To solve these problems, in this work, we propose a deep learning driven framework that can assess and quantify lesion indicators and outcome the prediction of severity of ILD. In detail, we first present a convolutional neural network that can segment and quantify five types of lesions including HC, RO, GGO, CONS, and EMPH from HRCT of ILD patients, and then we conduct quantitative analysis to select the features related to ILD based on the segmented lesions and clinical data. Finally, a multivariate prediction model based on nomogram to predict the severity of ILD is established by combining multiple typical lesions. Experimental results showed that three lesions of HC, RO, and GGO could accurately predict ILD staging independently or combined with other HRCT features. Based on the HRCT, the used multivariate model can achieve the highest AUC value of 0.755 for HC, and the lowest AUC value of 0.701 for RO in stage I, and obtain the highest AUC value of 0.803 for HC, and the lowest AUC value of 0.733 for RO in stage II. Additionally, our ILD scoring model could achieve an average accuracy of 0.812 (0.736-0.888) in predicting the severity of ILD via cross-validation. In summary, our proposed method provides effective segmentation of ILD lesions by a comprehensive deep-learning approach and confirms its potential effectiveness in improving diagnostic accuracy for clinicians.

Predictors and prognosis of pulmonary hypertension complicating interstitial lung disease in systemic sclerosis.

To identify those with concurrent pulmonary hypertension (PH) and interstitial lung disease (ILD) in systemic sclerosis (SSc) and determine their disease severity, therapeutic approach, and survival. Consecutive SSc patients enrolled in the Australian Scleroderma Cohort Study (ASCS) who were diagnosed on right heart catherisation with pulmonary hypertension were included. Logistic regression was used to determine the associations of ILD with PH hemodynamic parameters and therapeutic approach. Kaplan-Meier survival curves were used to estimate survival. Of 1,883 SSc patients, 164 (8.7%) developed incident PH over a median follow up of 4.3 (1.7-7.9) years. Of these, 43.9% had concurrent ILD at PH diagnosis (PH-ILD) and 56.1% had Group 1 PAH. Extensive ILD was present at PH diagnosis in 40.3%. Despite these distinct PH cohorts, a similar frequency of each PH cohort was treated with vasodilatory therapy at PH diagnosis, regardless of the presence or severity of ILD. The majority (87.5%) of those with extensive ILD and PH received upfront vasodilatory therapy at PH diagnosis with no difference in its tolerability or therapy cessation compared with Group 1 PAH. Although vasodilator therapy was not associated with a survival advantage in those with extensive ILD, its use was associated with an improvement in symptoms, physical function, and quality of life (QoL). Despite vasodilator therapy, survival in SSc-PH is poor, with the presence of concurrent ILD associated with worse survival. Although vasodilator therapy commenced at PH diagnosis does not portray an improved survival in PH with extensive ILD, it appears well tolerated and may improve symptoms, physical function, and QoL.

Forensic application of three interstitial pneumonia markers: search for new pneumonia markers in dead bodies.

In forensic cases, detailed identification of pneumonia is important. Our objective was to statistically determine the applicability of three interstitial lung disease (ILD) markers for forensic diagnosis using serum collected from dead bodies with various postmortem intervals (PMIs). We retrospectively analyzed the levels of postmortem serum Krebs von den Lungen-6 (KL-6) and pulmonary surfactant-associated proteins A and D (SP-A and SP-D) using 221 samples obtained during forensic autopsy at our facility from 2019 to 2023. We evaluated the diagnostic efficacy of ILD markers for various pneumonias against the pathological diagnosis, and examined the assessment of the severity of ILD. When comparing the ILD group with bacterial pneumonia (BP) versus the control group, there was a significant increase in KL-6 in the ILD group. When comparing the severe ILD (SILD) group with the mild ILD (MILD) group, there was a significant increase in KL-6 and SP-D in the SILD group. The optimal cutoff values for differentiating SILD were 607.0 U/mL for KL-6, 55.5ng/mL for SP-A, and 160.0ng/mL for SP-D, and the sensitivity/specificity (%) of KL-6, SP-A, and SP-D for SILD were 84.1/95.2, 55.6/85.7, and 66.7/74.6, respectively. This is the first study to examine KL-6 in postmortem serum in forensic medicine. By analyzing dead bodies with various PMIs, our results confirmed statistically that postmortem serum KL-6 specifically detects ILD, postmortem serum SP-A has high sensitivity to lung injury, and postmortem serum SP-D is potentially useful in assessing the severity of ILD.

Validation of a Dyspnea Visual Analogue Scale in Fibrotic Interstitial Lung Disease.

A visual analogue scale (VAS) is a simple and easily administered tool for measuring impact of disease; however, little is known about the use of a Dyspnea VAS in interstitial lung disease (ILD). To validate the use of a Dyspnea VAS in a large and heterogenous cohort of patients with fibrotic ILD, including its minimal clinically important difference (MCID), responsiveness to change, and prognostic significance. Patients with fibrotic ILD were identified from a large prospective registry. Validity of a 100mm Dyspnea VAS was assessed by testing its correlation in change score with other measures of ILD severity, including the University of California San Diego Shortness of Breath Questionnaire (UCSDSOBQ), King's Brief Interstitial Lung Disease quality of life questionnaire Breathlessness and Activities Domain (KBILD-B), European Quality of Life visual analogue scale (EQ-VAS), forced vital capacity (FVC), and diffusion capacity of the lung for carbon monoxide (DLCO). Responsiveness of the Dyspnea VAS was qualitatively confirmed based on there being an observable difference in the change in Dyspnea VAS across tertiles of change in anchor variables. The minimum clinically important difference (MCID) in Dyspnea VAS was calculated using both anchor (linear regression) and distribution (one-half standard deviation) approaches, with anchors including the above variables that had a correlation with Dyspnea VAS (|r|0.30). The association of Dyspnea VAS with time to death or transplant was determined. The cohort included 826 patients with fibrotic ILD, including 127 patients with follow-up measurements at 6 months. Mean baseline Dyspnea VAS was 5324mm. Dyspnea VAS change scores were moderately correlated with UCSDSOBQ (|r|=0.55) and KBILD-B (|r|=0.44), and weakly correlated with EQ-VAS (|r|=0.19), FVC% (|r|=0.21) and DLCO% (|r|=0.05). MCID was 2.7 to 4.5 using the more reliable anchor-based methods and 12.0 based on distribution-based methods. Dyspnea VAS was associated with time to death or transplant in unadjusted models and after adjustment for age and sex (hazard ratio 1.16 and 1.15 respectively, p<0.05 for both). This study provides support for the use of Dyspnea VAS in patients with fibrotic ILD, with an estimated anchor-based MCID of 5mm.

Histogram-Based Densitometry Index to Assess the Severity of Interstitial Lung Disease in Systemic Sclerosis in Standard and Low-Dose Computed Tomography.

Mean lung attenuation, skewness, and kurtosis are histogram-based densitometry variables that quantify systemic sclerosis-associated interstitial lung disease (SSc-ILD) and were recently merged into a computerized integrated index (CII). Our work tested the CII in low-dose 9-slice (reduced) and standard high-resolution computed tomography (CT) scans to evaluate extensive SSc-ILD and predict mortality. CT scans from patients with SSc-ILD were assessed using the software Horos to compute standard and reduced CIIs. Extensive ILD was determined following the Goh staging system. The association between CIIs and extensive ILD was analyzed with a generalized estimating equation regression model, the predictive ability of CIIs by the area under the receiver-operation characteristic curve (AUC), and the association between CIIs and death by Kaplan-Meier analysis. Among 243 patients with standard and reduced CT scans available, 157 CT scans from 119 patients with SSc-ILD constituted the derivation cohort. The validation cohort included 116 standard and 175 reduced CT scans. Both CIIs from standard (odds ratio [OR] 0.53, 95% CI 0.37-0.75; AUC 0.77, 95% CI 0.68-0.87) and reduced CT scans (OR 0.54, 95% CI 0.35-0.82; AUC 0.78, 95% CI 0.70-0.87) were significantly associated with extensive ILD. A threshold of CII ≤ -0.96 for standard CT scans and CII ≤ -1.85 for reduced CT scans detected extensive ILD with high sensitivity in both derivation and validation cohorts. Extensive ILD according to Goh staging (OR 2.94, 95% CI 1.10-7.82) and standard CII ≤ -0.96 (OR 1.78, 95% CI 1.24-2.56) significantly predicted mortality; a marginal P value was observed for reduced CII ≤ -1.85 (OR 1.27, 95% CI 0.93-1.75). Thresholds for both standard and reduced CII to identify extensive ILD were developed and validated, with an additional association with mortality. CIIs might help in clinical practice when radiology expertise is missing.

Rituximab compared to intravenous cyclophosphamide in adults with connective tissue disease-associated interstitial lung disease: the RECITAL RCT

Background Interstitial lung disease frequently complicates systemic autoimmune disorders including scleroderma, idiopathic inflammatory myositis and mixed connective tissue disease, resulting in considerable morbidity and mortality. Based on the results of trials undertaken in scleroderma, cyclophosphamide is the standard of care for individuals with severe or progressive connective tissue disease-associated interstitial lung disease. Observational studies suggest that the anti-CD20 monoclonal antibody, rituximab is an effective rescue therapy in treatment of refractory connective tissue disease-associated interstitial lung disease, but it has not been studied as first-line therapy in clinical trials. Objectives To compare the safety and efficacy of rituximab against that of cyclophosphamide as treatment for individuals with severe, progressive interstitial lung disease associated with scleroderma, idiopathic inflammatory myositis or mixed connective tissue disease. Methods This was a Phase IIb, multicentre, randomised, double-blind, double-dummy study assessing the superiority of rituximab compared with cyclophosphamide, conducted in rheumatology or interstitial lung disease units at 11 UK centres. The study recruited individuals with extensive and/or progressive connective tissue disease-associated interstitial lung disease, excluding those with significant comorbidities, including airflow obstruction. Participants were randomised 1 : 1 to receive either rituximab 1 g given intravenously, twice at an interval of 2 weeks, or intravenous cyclophosphamide given monthly for 6 months at a dose of 600 mg/m2 body surface area. The primary end point for the study was the change in forced vital capacity at 24 weeks. Secondary end points included safety and tolerability, corticosteroid exposure, forced vital capacity change at 48 weeks and patient-reported quality of life. A cost-effectiveness analysis was undertaken to assess the impact of rituximab use in the United Kingdom National Health Service. Results One hundred and one subjects (70 females) with a mean age of 56.3 years were randomised; 51 to rituximab and 50 to cyclophosphamide. Ninety-seven were included in the modified intention-to-treat population for the primary and secondary efficacy analyses (49 in the rituximab group and 48 in the cyclophosphamide group). 38.6% had scleroderma, 44.6% idiopathic inflammatory myositis and 16.8% mixed connective tissue disease. Four subjects withdrew prior to the first dose of therapy (two in each arm). At 24 weeks, both rituximab and cyclophosphamide improved forced vital capacity from baseline [(mean ± standard deviation) 97 ± 234 and 99 ± 329 ml, respectively]. Using an adjusted mixed-effects model corrected for diagnosis and baseline forced vital capacity the difference in forced vital capacity at 24 weeks between rituximab and cyclophosphamide was −40 ml (95% CI −153 to 74 ml), p = 0.49. Other physiological and quality-of-life parameters improved in both arms following treatment but were not statistically significantly different between groups. Numerically fewer adverse events were reported by subjects receiving rituximab. Corticosteroid exposure over the 48 weeks of the trial was numerically less in the rituximab arm [13,291 (±14,657) mg of hydrocortisone equivalent per subject in the cyclophosphamide arm versus 11,469 (±10,041) mg per subject in the rituximab group; these differences did not reach statistical significance]. Limitations of the study include a disproportionate number of subjects being recruited from a single centre and insufficient subjects in each subgroup to determine whether there were treatment differences between individual connective tissue diseases. Based on the results of the trial, from a UK healthcare payer perspective, rituximab is more cost-effective than cyclophosphamide as a treatment for severe or progressive connective tissue disease-interstitial lung disease. Conclusions Rituximab improved forced vital capacity and patient-reported quality of life at 24 weeks but was not superior to cyclophosphamide. Rituximab should be considered as a therapeutic alternative to cyclophosphamide in individuals with connective tissue disease-associated interstitial lung disease requiring systemic therapy. Future work should explore the role of repeated dosing of rituximab and the use of rituximab earlier in the course of connective tissue disease-associated interstitial lung disease. Trial registration This trial is registered as ISRCTN16474148. Funding This award was funded by the National Institute for Health and Care Research (NIHR) Efficacy and Mechanism Evaluation Programme (NIHR award ref: 11/116/03) and is published in full in Efficacy and Mechanism Evaluation; Vol. 11, No. 4. See the NIHR Funding and Awards website for further award information.

Localized Administration of Bcar3 siRNA via Nano-Self-Assembly to Treat Idiopathic Pulmonary Fibrosis by Disrupting Macrophage-Fibroblast Crosstalk.

Idiopathic pulmonary fibrosis (IPF) is a severe interstitial lung disease characterized by chronic lung injury leading to macrophage infiltration and fibroblast activation. However, there is no effective therapeutic strategy targeting the crucial crosstalk between macrophages and fibroblasts to halt IPF progression. Studies were conducted in IPF patients and fibrotic mice models to elucidate the role of Bcar3 in the pathogenesis of pulmonary fibrosis. The effect of Bcar3 on macrophage polarization, fibroblast activation, and related signaling pathways were next investigated to unravel the underlying mechanisms. Our study elucidates a marked increase in Bcar3 expression in lung tissues from IPF patients and fibrotic mice, recording 1.7 and 7.8-fold increases compared to control subjects, respectively. Additionally, Bcar3 was found to significantly enhance macrophage activation and fibroblast differentiation, observable in both in vivo and in vitro settings. Mechanistically, the upregulation of Bcar3 in macrophages was reliant on Stat6, while in fibroblasts, it depended on TGFβR1/Smad3. Furthermore, Bcar3 augmented IL-4/Stat6 pathway in macrophages and TGF-β/Smad3 pathway in fibroblasts, supporting a synergistic activation loop that expedited lung fibrogenesis. Notably, intratracheal injection of liposomes containing Bcar3 siRNA precisely delivered gene therapeutics to lung macrophages and fibroblasts, effectively reducing Bcar3 expression to 59% of baseline levels. Importantly, this intervention protected mice from lung fibrosis induced by either FITC or bleomycin, as well as human precision-cut lung slices against TGF-β1 stimulation. Our study underscores the pivotal role of Bcar3 in orchestrating the macrophage-fibroblast crosstalk during pulmonary fibrosis progression. Targeting Bcar3 emerges as a novel therapeutic avenue to halt IPF progression and enhance patient prognosis.

Assessment of the value of 6-min walk test to predict the severity of interstitial lung disease among Indian patients

Introduction: The prevalence of interstitial lung disease (ILD) is increasing. High-resolution computerized tomography (HRCT), despite having limitations, remains the choice of method for diagnosis and assessment of severity of ILD. Objective: To determine the efficacy of 6-min walk test to assess the severity of the ILD compared to HRCT. Methodology: A cross-sectional study was done among 40 patients with ILD in a tertiary hospital in Hyderabad. The data included age, gender, smoking, HRCT, 6-min walk test, spirometry, diffusion lung capacity and medical history. Mann–Whitney U test, Kruskal–Wallis test, and ROC curve were used to determine the outcomes. Results: The mean age of participants was 57.18 + 13.01 years. 62.5% never smoked. Overall, 50% had severe ILD, and the rest had mild to moderate. The distance walked per 6-min, SpO2 before and SpO2 after, was significantly lower (p = 0.001; 0.002; &lt;0.001, respectively) among patients with severe ILD than mild or moderate. The sensitivity and 1-specificity of the distance walked in 6-min to detect the severity of ILD was 0.90 and 0.31, respectively; sensitivity and 1-specificity of SpO2 before the test was 0.81 and 0.34, while that of SpO2 after the test was 0.90 and 0.17, respectively. Conclusion: This study found that the 6-min walk test is highly sensitive and specific for predicting the severity of ILD among patients. All three components of the 6-min walk test: distance, oxygen saturation before, and oxygen saturation after the test significantly lowered and were independent predictors of severe ILD.

Clinicopathological characteristics of everolimus-associated interstitial lung disease: A single-center consecutive analysis.

Everolimus, a mammalian target of rapamycin inhibitor used as an antineoplastic drug, is associated with a remarkably high incidence of interstitial lung disease (ILD). The clinical and pathological characteristics of ILD caused by everolimus have not been thoroughly investigated; therefore, we aimed to elucidate the features of everolimus-associated ILD. We retrospectively reviewed the medical records of patients who received everolimus for cancer treatment at our hospital. Patient backgrounds were compared between the ILD and non-ILD groups. Chest computed tomography (CT), changes in biomarkers, and lung histopathological features were analyzed for ILD cases. Sixty-six patients were reviewed, and ILD developed in 19. There were no differences in patient demographics between the ILD and non-ILD groups. The severity of ILD was grade 1 (G1) in 9 and grade 2 (G2) in 10 cases. Chest CT showed organizing pneumonia (OP) or a hypersensitive pneumonia pattern. The levels of lactate dehydrogenase, C-reactive protein, Krebs von den lungen-6, and surfactant protein-D (SP-D) at the onset of ILD were significantly higher than those at baseline. Analysis of G1 and G2 ILD subgroups showed a higher SP-D levels in the G2 subgroup. Five patients underwent lung biopsies; all specimens demonstrated alveolitis with lymphocytic infiltration and granulomatous lesions, and some had OP findings. Everolimus-associated ILD is mild and has a favorable prognosis. Patients with symptomatic ILD were more likely to have higher SP-D levels than those with asymptomatic ILD. Granulomatous lesions are an important pathological feature of everolimus-associated ILD.

Predictive factors for severe radiation-induced lung injury in patients with lung cancer and coexisting interstitial lung disease

Background and purposeThis study aimed to investigate the predictive factors of severe radiation-induced lung injury (RILI) in patients with lung cancer and coexisting interstitial lung disease (ILD) undergoing conventionally fractionated thoracic radiotherapy. Materials and methodsThe study includes consecutive patients treated with thoracic radiotherapy for lung cancer at two tertiary centers between 2010 and 2021. RILI severity was graded using the National Cancer Institute Common Terminology Criteria version 5.0, with severe RILI defined as toxicity grade ≥4, and symptomatic RILI as grade ≥2. The absolute neutrophil count (ANC), absolute lymphocyte count (ALC), and C-reactive protein were collected within 4 weeks before starting radiotherapy. Neutrophil–lymphocyte ratios (NLR) were calculated as ANC/ALC. The median follow-up was 9 (range, 6–114) months. ResultsAmong 54 patients, 22 (40.7 %) had severe RILI. On multivariate logistic regression analysis, high pretreatment ANC (p = 0.030, OR = 4.313), pretreatment NLR (p = 0.007, OR = 5.784), and ILD severity (p = 0.027, OR = 2.416) were significant predictors of severe RILI. Dosimetric factors were not associated with severe RP. Overall survival was significantly worse for patients with severe RILI than those without, with 1-year cumulative overall survival rates of 7.4 % and 62.8 %, respectively. ConclusionPretreatment blood NLR, ANC, and ILD severity were associated with severe RILI. Overall survival was dismal for patients with severe RILI.

Clinical and molecular analysis of a novel variant in heme oxygenase-1 deficiency: Unraveling its role in inflammation, heme metabolism, and pulmonary phenotype

Heme oxygenase 1 (HO-1) is the pivotal catalyst for the primary and rate-determining step in heme catabolism, playing a crucial role in mitigating heme-induced oxidative damage. Pathogenic variants in the HMOX1 gene which encodes HO-1, are responsible for a severe, multisystem disease characterized by recurrent inflammatory episodes, organ failure, and an ultimately fatal course. Chronic hemolysis and abnormally low bilirubin levels are cardinal laboratory features of this disorder. In this study, we describe a patient with severe interstitial lung disease, frequent episodes of hyperinflammation non-responsive to immunosuppression, and fatal pulmonary hemorrhage. Employing exome sequencing, we identified two protein truncating variants in HMOX1, c.262_268delinsCC (p.Ala88Profs*51) and a previously unreported variant, c.55dupG (p.Glu19Glyfs*14). Functional analysis in patient-derived lymphoblastoid cells unveiled the complete absence of HO-1 protein expression and a marked reduction in cell viability upon exposure to hemin. These findings confirm the pathogenicity of the identified HMOX1 variants, further underscoring their association with severe pulmonary manifestations . This study describes the profound clinical consequences stemming from disruptions in redox metabolism.

Aggressive multi-combination therapy for anti-MDA5 antibody-positive dermatomyositis-rapidly progressive interstitial lung disease.

To elucidate the efficacy and safety of aggressive multi-combination therapy with mycophenolate mofetil, rituximab, and plasma exchange or polymyxin B immobilized fiber column direct hemoperfusion followed by conventional therapy with corticosteroids, calcineurin inhibitors, and intravenous pulse cyclophosphamide in patients with rapidly progressive interstitial lung disease (RPILD) with anti-melanoma differentiation-associated gene 5 (MDA5)-antibody-positive dermatomyositis (DM). A total of 23 patients with anti-MDA5 antibody-positive DM-RPILD were enrolled, with nine patients in Group A (treated conventionally before March 2015) and 14 patients in Group B (received aggressive treatment after April 2015). Pretreatment severity of interstitial lung disease (ILD) did not differ between the two groups. However, Group B exhibited a higher cumulative survival rate at 48 weeks than Group A (64.3% vs. 33.3%). The corticosteroid dose, divided by the initial dose at 3 months and 12 months, was significantly lower in Group B than in Group A (p = .046 and .026, respectively). Among the ILD-related deaths in Group B, there was a tendency toward a higher proportion of males and more severe ILD. The incidence of infection did not differ between the groups, but leukopenia was more common in Group B. This aggressive multi-combination therapy may improve the survival outcome of patients with anti-MDA5 antibody-positive DM-RPILD. However, careful management of complications, such as opportunistic infections and leukopenia, is essential. Future refinement through longitudinal investigations tracking the long-term efficacy, safety, and cost-effectiveness of this treatment strategy is needed.

Exploring the mechanism of Gentiana rigescens Franch. in the treatment of pulmonary fibrosis based on network pharmacology

Pulmonary fibrosis (PF) is a severe chronic interstitial lung disease with high mortality, and there is currently a lack of definite and effective treatment methods. Studies have found that gentiopicroside, a secoiridoid glycoside compound derived from plants of the Gentiana genus, can significantly improve pulmonary inflammation and fibrosis lesions in mice with pulmonary fibrosis. However, the mechanism of its anti-fibrotic effect is unclear. Therefore, in this study, we employed network pharmacology's virtual computer technology to investigate the potential mechanism underlying the anti-pulmonary fibrosis effect of Gentianae Radix et Rhizome (Longdan in Chinese, GRR). Our findings offer valuable theoretical insights and serve as a guiding reference for future experimental investigations. A total of 10 active compounds and 920 drug-target proteins were identified from the TCMSP database. The compound-target-pathway-disease network showed that GRR could potentially treat PF by regulating the MDM2, ERBB2 and VEGFA, signaling pathways through its key targets, including AKT1, TNF, and MAPK1. The protein‒protein interaction network revealed that these targets had strong interactions with each other, indicating a potential synergistic effect of GRR in treating PF. The GO and KEGG enrichment analyses further supported the potential anti-pulmonary fibrosis mechanisms of GRR, including regulating the inflammatory response, ECM-receptor interaction, and TGF-beta signaling pathways. Our study provides a systematic analysis of the potential anti-pulmonary fibrosis mechanisms of GRR based on network pharmacology. These findings could contribute to the development of novel treatments for PF and provide a basis for further experimental studies.

Gender differences in patients with anti-MDA5-positive dermatomyositis: a cohort study of 251 cases.

To investigate the impact of sex differences on the clinical characteristics and prognosis of patients with anti-melanoma differentiation-associated gene 5-positive dermatomyositis (MDA5+ DM). We retrospectively analyzed a cohort of 251 patients with MDA5+ DM, including 71 in the male group and 180 in the female group. A multivariate logistic regression model was built to analyze independent risk factors for RPILD in each group. An ROC curve was drawn to evaluate the predictive value of independent risk factors. Kaplan‒Meier analysis was used to compare the cumulative survival rates, while the log-rank test was used to test for significant differences between the two groups. Patients in the male group had a significantly higher prevalence of heliotrope rash, V sign, severe interstitial lung disease (ILD), and rapidly progressive interstitial lung disease (RPILD) than those in the female group. Anti-Ro52 positivity, high CRP level and short disease were identified as independent risk factors for RPILD in both male and female groups by multivariate logistic regression analysis. The mortality rates of males and females were 33.8% and 22.0%, respectively, and the survival time of patients in the male group was shorter than that in the female group. Male patients with MDA5+ DM exhibit an increased risk of RPILD, elevated mortality rates and reduced overall survival time compared to their female counterparts, and anti-Ro52 positivity may be an unfavorable prognostic factor for these patients. Key Points • The prevalence of solar rash, V sign, severe interstitial lung disease (ILD) and rapidly progressive interstitial lung disease (RPILD) in anti-MDA5-positive female patients was significantly lower than that in male patients. • Positive Anti-Ro52, high CRP level, and short course of disease were independent risk factors for RPILD in both men and women. • Female patients exhibited a lower mortality rate than male patients (22.0% vs 33.8%) and demonstrated longer survival time.

Significance of serum Krebs von den Lungen-6 in systemic sclerosis

BackgroundSystemic sclerosis (SSc) is a well-known multi-system connective tissue disease, it has an unidentified aetiology that is characterised by abnormal immune system activation, vascular injury, which may progress to faulty neovascularization and inadequate vessel remodelling, and tissue scarring of the skin, lungs, and other internal viscera. Krebs von den Lungen-6 is a kind of transmembrane glycoprotein of type II alveolar epithelial cells and is specific for determining its damage. Regardless of the cause, serum Krebs von den Lungen-6 levels have been investigated in interstitial lung disease (ILD) of several etiologies and have been found to be a significant serum marker for ILD. The current research aims to look into the relationship between serum Krebs von den Lungen-6 levels and disease severity and clinical manifestations, specifically interstitial pulmonary fibrosis, in patients with SSc. In this study, 30 patients with systemic sclerosis and 30 control subjects—15 dermatomyositis patients and 15 healthy volunteers— were also incorporated to see if the change in serum Krebs von den Lungen-6 levels is specific for SSc as dermatomyositis is another connective tissue disorder with lung affection.ResultsA statistically significant difference (P < 0.001) in the median value of Krebs von den Lungen-6 when compared to the control groups was observed, which was 447.95 (145.68–817.98) in the SSc patients group, 158.80 (130.00–730.70) in the dermatomyositis group, and 48.10 (39.50–103.90) in the healthy control group. A significantly higher median value of Krebs von den Lungen-6 in ground glass, honeycombing, and nodular HRCT was established, with P-value (P < 0.001). There was a highly statistically significant discrepancy in the median Krebs von den Lungen-6 value between patients with ILD (717.7) and patients without ILD (145.7) with P-value (P < 0.001). A statistically significant positive correlation was found between Krebs von den Lungen-6 (U/ml) and Disease duration (years), Medsger severity scale, Digital ulceration, modified Rodnan skin score (MRSS), and P-value (P < 0.05).ConclusionKrebs von den Lungen-6 could be a scleroderma biomarker. It has been linked to the development and severity of interstitial lung disease in systemic sclerosis patients and may shed light on the pathophysiology of some fibrotic lung changes.