An Official ATS/ERS/JRS/ALAT Clinical Practice Guideline: Treatment of Idiopathic Pulmonary Fibrosis. An Update of the 2011 Clinical Practice Guideline

Early-Life Exposure to Tobacco Smoke and the Risk of Idiopathic Pulmonary Fibrosis: A Population-Based Cohort Study

Rationale: Tobacco smoking is a well-established risk factor for idiopathic pulmonary fibrosis (IPF), yet the influence of early-life tobacco exposure on future IPF risk remains poorly understood. Objectives: We sought to test the hypothesis that early-life tobacco exposure may elevate the risk of developing IPF, with this effect potentially modified by genetic susceptibility to IPF and mediated through accelerated biological aging. Methods: Using data from over 430,000 participants in the UK Biobank, we performed a prospective cohort study to examine the associations of maternal smoking around birth and age of smoking initiation with IPF risk. We evaluated the combined effects and interactions between early-life tobacco exposure and genetic susceptibility to IPF, which were quantified using polygenic risk scores. We assessed biological aging, as measured by telomere length and phenotypic age, as potential mediators in the associations between early-life tobacco exposure and IPF risk. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results: Maternal smoking around birth was associated with a higher risk of IPF (HR = 1.26; 95% CI = 1.11-1.43). Compared with never-smokers, individuals who initiated smoking in childhood (HR = 3.65; 95% CI = 3.02-4.41), adolescence (HR = 2.64; 95% CI = 2.28-3.05), and adulthood (HR = 2.09; 95% CI = 1.79-2.44) exhibited increased IPF risk (P for trend <0.001). An additive interaction was observed between age of smoking initiation and genetic risk for IPF. Individuals with high genetic risk, maternal smoking exposure, and childhood smoking initiation had a 16-fold greater risk of IPF (HR = 16.47; 95% CI = 9.57-28.32), compared with those with low genetic risk and no tobacco exposure. Telomere length and phenotypic age each mediated approximately 10% of the effect of maternal smoking on IPF, with weaker mediation effects observed for later ages of smoking initiation. Conclusions: Early-life tobacco exposure may elevate the risk of IPF, with effects modified by genetic susceptibility and partially mediated through accelerated biological aging.

Idiopathic Pulmonary Fibrosis, Today and Tomorrow: Certainties and New Therapeutic Horizons

Idiopathic pulmonary fibrosis (IPF) represents a clinical and therapeutic challenge characterized by progressive fibrosis and destruction of the lung architecture. The pathogenesis of IPF has been long debated; while it is generally believed that repeated lung injury and abnormal wound repair are the main pathogenetic mechanisms, clear understanding of disease development and efficacious treatment remain important unmet needs. Indeed, current standard of care (i.e., the antifibrotic drugs pirfenidone and nintedanib) can slow down lung function decline and disease progression without halting the disease. In the last 2 decades, several clinical trials in IPF have been completed mostly with negative results. Yet, unprecedented numbers of clinical trials of pharmacological interventions are currently being conducted. In this review, we summarize and critically discuss the current and future treatment landscape of IPF, with emphasis on the most promising developmental molecules.

Clinical significance of anti-neutrophil cytoplasmic antibody in idiopathic interstitial pneumonia: a retrospective observational study

BACKGROUND

Patients with anti-neutrophil cytoplasmic antibody (ANCA)-positive interstitial lung disease (ILD) but without evidence of systemic vasculitis have been reported in studies and are classified as isolated ANCA-positive idiopathic interstitial pneumonia (IIP). However, the clinical significance of ANCA, particularly myeloperoxidase (MPO) -ANCA in IIP remains poorly understood. This study aims to investigate the differences between ANCA-positive and ANCA-negative IIP patients and further explore the impact of MPO-ANCA on clinical manifestations and prognostic outcomes.

METHODS

We reviewed 408 ILD patients with available ANCA results from January 2012 to September 2021. 61 patients diagnosed with microscopic polyangiitis-associated ILD were not included in the analysis. A comparative analysis was performed between 61 isolated ANCA-positive IIP patients (ANCA-IIP group) and 286 ANCA-negative IIP patients (IIP group). We further conducted subgroup analyses based on the status of MPO-ANCA.

RESULTS

Baseline clinical characteristics, pulmonary function tests, radiological features and all-cause mortality were similar between ANCA-IIP and IIP groups. When comparing the MPO-ANCA-IIP group with the IIP group and the non-MPO-ANCA-IIP group separately, a higher proportion of fibrotic features was observed on imaging (P = 0.004 vs IIP group; P = 0.031 vs non-MPO-ANCA-IIP group). After one year of treatment, the MPO-ANCA-IIP group showed a significantly greater decline in pulmonary function parameters compared to both the IIP group and the non-MPO-ANCA-IIP group. The frequency of pulmonary function decline was significantly higher in the MPO-ANCA-IIP group compared to the non-MPO-ANCA-IIP group (P = 0.026). Additionally, MPO-ANCA was not found to be statistically associated with mortality among patients with IIP.

CONCLUSION

ANCA-IIP patients had similar clinical characteristics and prognoses with IIP patients. MPO-ANCA-IIP patients had more prominent fibrosis on imaging and a greater decline in pulmonary function following treatment. Special attention should be paid to MPO-ANCA positivity during the diagnosis and treatment of IIP patients.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT04413149, May 2020.

Patient characteristics and pharmacologic treatment patterns in antifibrotic-treated patients with fibrosing interstitial lung diseases: real-world results from a claims database

BACKGROUND

Antifibrotics have been approved for use in many countries, including Japan, based on the results of several phase III clinical trials in patients with IPF, SSc-ILD, and PPF, which showed slower lung function decline with antifibrotic treatment. There is a paucity of information on the real-world use of antifibrotics in clinical practice.

METHODS

Baseline characteristics, comorbidities, and drugs used prior to and concomitant with antifibrotics were collected for patients with IPF, SSc-ILD, and PPF using a health insurance claims database in Japan from 1 January 2013 to 30 June 2023. Descriptive statistics were generated for all study variables.

RESULTS

This study included 657 nintedanib users with IPF; 418 pirfenidone users with IPF; 4160 nintedanib users with PPF; 18,403 users of glucocorticoids/immunosuppressants for ILD treatment with PPF; 676 nintedanib users with SSc-ILD; and 698 users of glucocorticoids/immunosuppressants for ILD treatment with SSc-ILD. At index, pirfenidone users with IPF were the oldest (mean [SD] 74.8 [7.3] years), and nintedanib users with SSc-ILD were the youngest (mean [SD] 65.6 [11.7] years). In nintedanib users with IPF, 76.7% were prescribed nintedanib as monotherapy, and 75.6% of pirfenidone users were prescribed pirfenidone, as monotherapy. In patients with IPF, 75.2% were prescribed nintedanib, and 76.1% were prescribed pirfenidone, as first-line therapy. In patients with SSc-ILD, 34.9% were prescribed nintedanib as monotherapy for ILD treatment, and 38.6% as first-line therapy. Approximately half of patients with PPF were prescribed nintedanib concomitantly with other glucocorticoids/immunosuppressant drugs, and after one or more glucocorticoids/immunosuppressant drugs. The most common concomitant drug in all patient groups was glucocorticoids. In patients with IPF, 18.6% of nintedanib users and 18.2% of pirfenidone users were prescribed glucocorticoids concomitantly. Concomitant glucocorticoid use was 52.7% for nintedanib users with SSc-ILD, and 44.1% for nintedanib users with PPF.

CONCLUSIONS

These results provide real-world evidence of antifibrotic use in clinical practice. Most patients with IPF were prescribed antifibrotics as monotherapy for ILD treatment whereas antifibrotics were used concomitantly with glucocorticoids/immunosuppressants in many patients with SSc-ILD and PPF. While most patients with IPF were prescribed antifibrotics as first-line therapy, patients with SSc-ILD and PPF were more likely to be prescribed nintedanib as second-line or later-line treatment after glucocorticoids/immunosuppressants.

A nomogram-based clinical prediction model for adverse clinical outcomes in non-HIV Pneumocystis jirovecii pneumonia patients

BACKGROUND

Non-human immunodeficiency virus (HIV) immunocompromised patients with Pneumocystis jirovecii pneumonia (PJP) face rapid progression and high mortality, necessitating a predictive model to identify patients at risk of adverse clinical outcomes for timely interventions and improved stratification.

METHODS

Patients admitted between January 2011 and June 2024 at Beijing Chao-Yang Hospital were retrospectively analyzed. Collected data included patients' demographics, smoking status, comorbidities, immunosuppressive diseases, blood laboratory tests, in-hospital treatment, and adverse clinical outcomes. Predictor selection was performed using the least absolute shrinkage and selection operator (LASSO) and logistic regression, with selected features incorporated into a nomogram. Internal validation was conducted using a 500-bootstrap resampling method to ensure model robustness. Model performance was assessed via the area under the receiver operating curve (AUC), calibration plots, decision curve analysis (DCA), and clinical impact curve (CIC).

RESULTS

Among the 431 patients, 243 (56.4%) experienced adverse clinical outcomes. LASSO regression screened 21 variables, selecting 9 predictors with non-zero coefficients through 10-fold cross-validation at lambda.1se = 0.0453 (log(lambda.1se) = -3.092). Multivariate logistic regression identified 7 independent risk factors for adverse clinical outcomes: smoking status, cytomegalovirus infection, diabetes, neutrophil-lymphocyte ratio (NLR), lactate dehydrogenase (LDH), PaO2/FiO2 (PFR), and lymphocyte subset. These factors were incorporated into a nomogram, achieving an AUC of 0.89 (95% CI: 0.86-0.92), with the Hosmer-Lemeshow test (p = 0.134) and calibration curves showing strong agreement between predicted and observed outcomes. Internal validation via 500-bootstrap resampling yielded a bias-corrected AUC of 0.83 (95% CI: 0.80-0.86). DCA demonstrated strong clinical decision-making utility, while the CIC confirmed its practical reliability.

CONCLUSIONS

Regression analysis identified smoking status, CMV infection, diabetes, NLR, LDH, PFR, and lymphocyte subset as independent risk factors for adverse clinical outcomes in non-HIV PJP patients. The predictive model constructed from these factors exhibited robust accuracy and reliability.

Lamellarin D Acts as an Inhibitor of Type I Collagen Production

Idiopathic pulmonary fibrosis (IPF) is a progressive and chronic interstitial lung disease characterized by irreversible loss of lung function and a poor prognosis. Type I collagen, a major component of the extracellular matrix, plays a central role in the pathogenesis of fibrosis and is considered a key molecular target for therapeutic intervention. While current anti-fibrotic therapies demonstrate limited efficacy in slowing disease progression, their clinical impact remains suboptimal due to poor pharmacokinetic properties and non-curative therapy. Moreover, the development of effective anti-fibrotic agents targeting collagen synthesis is hindered by the absence of robust, cost-effective, high-throughput drug screening platforms. In this study, we established a novel screening system designed to identify small molecules that inhibit the expression of the COL1A2 gene, which encodes type I collagen. Utilizing this system, we screened a library of natural and synthetic compounds developed at Nagasaki University and identified lamellarin D as a potent inhibitor of COL1A2 expression and subsequent type I collagen production. These findings suggest that lamellarin D, through its unique molecular mechanism, may serve as the foundation for the development of a new class of IPF treatments aimed at targeting the underlying fibrotic processes.

Idiopathic pleuroparenchymal fibroelastosis: diagnosis and management

INTRODUCTION

Idiopathic pleuroparenchymal fibroelastosis (iPPFE) is a rare progressive interstitial lung disease characterized by upper-lobe fibrosis, severe restrictive impairment, and poor prognosis. Unlike idiopathic pulmonary fibrosis, in which acute exacerbations, chronic respiratory failure, and lung cancer are the major causes of death, iPPFE primarily leads to progressive respiratory failure, often complicated by malnutrition and recurrent pneumothorax. Despite growing recognition, its pathogenesis remains unclear and no effective treatments exist.

AREAS COVERED

This review summarizes the epidemiological, clinical, radiological, and pathological features of iPPFE, as well as diagnostic and prognostic advancements. Key prognostic factors include weight loss, reduced forced vital capacity, hypercapnia, and lower-lobe interstitial pneumonia. Serum biomarkers (e.g. latent transforming growth factor-beta binding protein-4) are being explored for early detection and prognostic purposes. Although antifibrotic agents show limited efficacy, supportive care - pulmonary rehabilitation, nutritional management, and pneumothorax prevention - remains essential. Research on the fibroelastotic pathways may inform the development of future therapies.

EXPERT OPINION

IPPFE remains a challenging disease. Therefore, early diagnosis and comprehensive management of this condition are crucial. Future research should refine prognostic models and explore novel therapeutic approaches for treating fibroelastosis. Lung transplantation may be an option for select patients. Further studies are required to optimize these outcomes.

Development of cysteine-sensitive bimodal probes for in situ monitoring of early-stage pulmonary fibrosis progression and therapeutic effects

Pulmonary fibrosis (PF) is a chronic interstitial lung disease characterized by excessive extracellular matrix deposition and lung scarring, leading to impaired lung function, severe respiratory distress, and potentially fatal outcomes. Early diagnosis of PF is crucial for optimizing treatment strategies to improve patient prognosis. However, an activated near-infrared fluorescent (NIRF) and photoacoustic (PA) bimodal probe for non-invasive in situ imaging of PF is still lacking. In this study, we developed a novel cysteine-sensitive NIRF/PA dual-modal probe, MR-Cys, for in situ monitoring of early progression and the therapeutic response in a mouse model of PF. The probe MR-Cys selectively detects cysteine (Cys) levels in vivo, thereby activating both NIRF and PA signals. Using NIRF/PA dual-modal imaging technology, MR-Cys successfully tracked fluctuations in Cys levels within the PF mouse model. After treatment with nintedanib (OFEV), a notable decrease in both PA and NIRF signal intensities was observed in the treated mice, indicating that MR-Cys can be used to assess the therapeutic efficacy for PF. Therefore, MR-Cys not only holds great promise for early detection of pulmonary fibrosis progression, but also offers a precise monitoring tool for the optimization of personalized treatment plans.

Molecular Hydrogen Ameliorates Anti-Desmoglein 1 Antibody-Induced Pemphigus-Associated Interstitial Lung Disease by Inhibiting Oxidative Stress

Pemphigus-associated interstitial lung disease (P-ILD) is a severe complication observed in pemphigus patients that is characterized by pulmonary interstitial inflammation and fibrosis. This study investigated the role of anti-desmoglein (Dsg) 1/3 antibodies in P-ILD pathogenesis and evaluated the therapeutic potential of molecular hydrogen (H2). Using a BALB/cJGpt mouse model, we demonstrated that anti-Dsg 1 antibodies, but not anti-Dsg 3 antibodies, induced interstitial inflammation and fibrosis. Immunofluorescence staining confirmed IgG deposition in the alveolar epithelium, suggesting immune complex formation and epithelial damage. Gene expression analysis revealed elevated pro-inflammatory cytokines (IL-1β, IL-13) and upregulated pro-fibrotic markers (α-SMA, S100A4, TGF-β, and collagen genes) in P-ILD progression. Elevated oxidative stress and impaired ROS metabolism further implied the role of oxidative damage in disease pathogenesis. To assess H2's therapeutic potential, hydrogen-rich water was administered to P-ILD mice. H2 treatment significantly reduced oxidative stress, attenuated interstitial inflammation, and prevented pulmonary fibrosis. These protective effects were attributed to H2's antioxidant properties, which restored the pro-oxidant-antioxidant balance. Our findings underscore the critical role of anti-Dsg 1 antibodies and oxidative stress in P-ILD and highlight H2 as a promising therapeutic agent for mitigating anti-Dsg 1 antibody-induced lung injury.

An Elastase Inhibitor ShSPI from Centipede Attenuates Bleomycin-Induced Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterized by the fibrotic thickening of the alveolar walls, resulting in compromised gas exchange, restricted ventilation, and respiratory failure. It has been indicated that elastase inhibitors reduced the severity of IPF by neutralizing excessive elastase levels in the lungs. ShSPI is an elastase inhibitor derived from centipede toxin. The present study evaluates the therapeutic effects of ShSPI in a bleomycin-induced idiopathic pulmonary fibrosis model. According to the results, ShSPI markedly reduced the weight loss, showing the improvement of health status in bleomycin-induced mice. Its robust antifibrotic effects were evidenced by the mitigation of alveolar structural damage, reduction in inflammatory cell infiltration, inhibition of collagen deposition, and suppression of fibrotic nodule formation. ShSPI effectively attenuated inflammatory responses by downregulating pro-inflammatory factors (IL-6, IL-1β, and MCP-1) and upregulating the anti-inflammatory factor interleukin-10 (IL-10). After delivered via inhalation, ShSPI exhibited favorable pharmacokinetic properties. It could be detected at 8 h at doses of 1 mg/kg and achieved maximum plasma concentrations (Cmax) of 188.00 ± 64.40 ng/mL in vivo. At high doses (160 mg/kg), ShSPI maintained a strong safety profile, with no detectable toxicity observed. This feature shows the therapeutic potential of ShSPI in the treatment of idiopathic pulmonary fibrosis and provides valuable evidence for its development as a novel peptide-based therapy.

Characteristics, clinical findings, and treatment of idiopathic pulmonary fibrosis in Japanese patients registered with a medical subsidy system for intractable diseases

BACKGROUND

The Japanese government operates a medical subsidy system for intractable diseases, including idiopathic pulmonary fibrosis (IPF). Registering with this system requires filling out a clinical survey form, which encompasses multiple survey items regarding the patient's disease and functional status. In this study, we retrospectively analyzed the forms of new applicants with IPF in 2019 to evaluate the clinical and functional characteristics.

METHODS

The following patient data were collected: sex, age, smoking status, history of surgical lung biopsy, disease severity (using Japanese severity classification [JSC]), serum biomarkers, findings on chest high-resolution computed tomography (HRCT), functional status, symptoms, and treatment.

RESULTS

Of the 4796 patients reviewed (76.1 % males; mean age = 73.4 ± 8.1 years), 23.6 % had a mild disease (JSC stages I-II) and 76.4 % had a severe disease (stages III-IV). The HRCT of most patients revealed honeycombing, traction bronchiectasis and/or bronchiolectasis, reticular shadows, and subpleural shadows. The positivity rates for elevated serum levels of Krebs von Lungen-6 (KL-6) and surfactant protein-D (SP-D) were 92.6 % and 89.3 %, respectively. As the severity increased, the biomarker positivity rate increased. Approximately half of the patients with milder diseases experienced transportation challenges, and 30 % complained of pain and/or discomfort and anxiety and/or depression.

CONCLUSIONS

In approximately 90 % of patients, serum KL-6 and SP-D levels increased and the positive rate increased as the disease severity increased. Even patients with mild diseases experience challenges in transportation as well as pain, discomfort, anxiety, or depression.

Expanding the horizons of bicyclol in multiple diseases: Mechanisms, therapeutic implications and challenges

Bicyclol, a drug stemmed from the traditional Chinese medicine Schisandra chinensis, has been widely utilized in clinical practice due to its efficacy and safety to manage hepatopathy. Its diverse biological properties-including antiviral, anti-inflammatory, antifibrotic, immunomodulatory, antioxidative, antisteatotic, and antitumor effects-underscore its significant medicinal effects in versatile hepatic disorders, incorporating viral hepatitis, non-alcoholic fatty liver disease, hepatocellular carcinoma, acute hepatic failure, hepatic fibrosis as well as drug-induced liver injury. Furthermore, ongoing researches into the molecular mechanisms, biological activities and mode of actions concerning bicyclol have uncovered its potential therapeutic implications in other multiple diseases/conditions. Studies have indicated promising efficacy pertaining to bicyclol to treat idiopathic pulmonary fibrosis, acute lung injury, cerebral ischemia/reperfusion injury, renal dysfunction, renal cell carcinoma, and cardiovascular diseases. Accordingly, this narrative review article summarizes the current understanding of diverse biological activities and underpinning mechanisms of bicyclol across a range of diseases, as well as its pharmacokinetics, toxicity profile and shed light on future perspectives.

Hypnotics and Mortality in Idiopathic Pulmonary Fibrosis: Hospital and National Data-Based Analysis

BACKGROUND

Patients with idiopathic pulmonary fibrosis (IPF) may experience insomnia and use hypnotics. However, the effect of the use of hypnotics on their clinical course remains unclear.

RESEARCH QUESTION

Is the use of hypnotics associated with an increased risk of mortality in patients with IPF?

STUDY DESIGN AND METHODS

This study included 99 patients with IPF from the Hamamatsu hospital-based cohort and 123 patients with IPF from the Seirei hospital-based cohort, as well as 30,218 patients with IPF from the National Database of Health Insurance Claims and Specific Health Checkups of Japan (the NDB cohort). To analyze the association of hypnotics use with outcomes avoiding immortal time bias, multivariable Cox models with time-dependent covariates and target trial emulation with a new user design were used for the hospital- and NDB-based cohorts.

RESULTS

In the cohorts studied, the 3-year cumulative incidence of new use of hypnotics following the IPF diagnosis ranged from 13.4% to 24.1%. In both hospital-based cohorts, the continuous use of hypnotics was associated with an increased risk of all-cause mortality and disease progression. In the NDB cohort, the continuous use of hypnotics was also associated with an increased risk of all-cause mortality. Subgroup analysis found associations between the continuous use of hypnotics and increased mortality regardless of sex and comorbidities, excluding certain subpopulations.

INTERPRETATION

This study found that continuous use of hypnotics was associated with an increased risk of mortality in patients with IPF. Given the relatively high cumulative incidence of hypnotics use in this population, there is an urgent need to reassess the appropriate use of hypnotics for patients with IPF.

Proteomic profiling identifies classic Hodgkin lymphoma patients at risk of bleomycin pulmonary toxicity

Advances in treating classic Hodgkin lymphoma (cHL) have improved cure rates, with overall survival exceeding 80%, resulting in a growing population of survivors at risk of long-term complications, particularly cardiac and pulmonary toxicity. Bleomycin, a key component of combination chemotherapy, is associated with bleomycin-induced pulmonary toxicity (BPT). Using label-free quantification nano liquid chromatography-tandem mass spectrometry, protein expression in diagnostic lymphoma samples from patients with and without BPT was compared. Results showed differential protein expression and disrupted cellular pathways, suggesting biological differences in BPT risk. Immunohistochemical analysis revealed higher expression of JAK3, BID, and MMP9, and lower expression of CD20, TPD52, and PIK3R4 in patients with BPT. High BID and low CD20 expression were associated with inferior overall survival, while high BID and low JAK3 and CD20 expression were linked to poorer progression-free survival. These findings highlight altered protein profiles in pretreatment cHL biopsies associated with BPT development.

Calcium-Sensing Receptor as a Novel Target for the Treatment of Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a disease with a poor prognosis and no curative therapies. Fibroblast activation by transforming growth factor β1 (TGFβ1) and disrupted metabolic pathways, including the arginine-polyamine pathway, play crucial roles in IPF development. Polyamines are agonists of the calcium/cation-sensing receptor (CaSR), activation of which is detrimental for asthma and pulmonary hypertension, but its role in IPF is unknown. To address this question, we evaluated polyamine abundance using metabolomic analysis of IPF patient saliva. Furthermore, we examined CaSR functional expression in human lung fibroblasts (HLFs), assessed the anti-fibrotic effects of a CaSR antagonist, NPS2143, in TGFβ1-activated normal and IPF HLFs by RNA sequencing and immunofluorescence imaging, respectively; and NPS2143 effects on polyamine synthesis in HLFs by immunoassays. Our results demonstrate that polyamine metabolites are increased in IPF patient saliva. Polyamines activate fibroblast CaSR in vitro, elevating intracellular calcium concentration. CaSR inhibition reduced TGFβ1-induced polyamine and pro-fibrotic factor expression in normal and IPF HLFs. TGFβ1 directly stimulated polyamine release by HLFs, an effect that was blocked by NPS2143. This suggests that TGFβ1 promotes CaSR activation through increased polyamine expression, driving a pro-fibrotic response. By halting some polyamine-induced pro-fibrotic changes, CaSR antagonists exhibit disease-modifying potential in IPF onset and development.

Fibrotic Pulmonary Sarcoidosis-From Pathogenesis to Management

Sarcoidosis is a multiorgan, granulomatous disease of an unknown etiology. The characteristic feature of the disease is the formation of noncaseating granulomas. Spontaneous resolution occurs in most patients, but the clinical course may be chronic or progressive, complicated by pulmonary fibrosis, which is a major cause of mortality in sarcoidosis. Recent studies have provided new information on the immunological mechanisms of pulmonary fibrosis. Its pathogenesis includes the alteration of lymphocyte activity and the imbalance between their subpopulations, the polarization of macrophages to the profibrotic phenotype, and an imbalance between the activity of metalloproteinases and their tissue inhibitors. A multidisciplinary approach is required for the optimal management of fibrotic pulmonary sarcoidosis. Clinical symptoms, serum biomarkers, imaging, pulmonary function test results, other organ involvement, comorbidities, and complications should be considered when assessing disease activity and selecting the most appropriate treatment. The use of anti-inflammatory drugs is often discussed. There has been no consensus reached on whether antifibrotic agents should be added or used in monotherapy as initial treatment in such cases. This article will review all the information on fibrotic pulmonary sarcoidosis and present factors associated with fibrosis development, prognosis, and treatment options.

Targeted therapy for idiopathic pulmonary fibrosis: a bibliometric analysis of 2004-2024

Background

Idiopathic pulmonary fibrosis (IPF) is a progressive and irreversible interstitial lung disease characterized by high mortality rates. An expanding body of evidence highlights the critical role of targeted therapies in the management of IPF. Nevertheless, there is a paucity of bibliometric studies that have comprehensively assessed this domain. This study seeks to examine global literature production and research trends related to targeted therapies for IPF.

Method

A literature search was conducted using the Web of Science Core Collection, encompassing publications from 2004 to 2024, focusing on targeted therapies for IPF. The bibliometric analysis utilized tools such as VOSviewer, CiteSpace, and the "bibliometrix" package in R.

Results

A total of 2,779 papers were included in the analysis, demonstrating a general trend of continuous growth in the number of publications over time. The United States contributed the highest number of publications, totaling 1,052, while France achieved the highest average citation rate at 75.74. The University of Michigan Medical School was the leading institution in terms of publication output, with 88 papers. Principal Investigator Naftali Kaminski was identified as the most prolific researcher in the field. The American Journal of Respiratory Cell and Molecular Biology emerged as the journal with the highest number of publications, featuring 98 articles. In recent years, the research has emerged surrounding targeted therapies for IPF, particularly focusing on agents such as TGF-β, pathogenesis, and autotaxin inhibitor.

Conclusion

In this bibliometric study, we systematically analyze research trends related to targeted therapies for IPF, elucidating recent research frontiers and emerging directions. The selected keywords-idiopathic pulmonary fibrosis, targeted therapy, bibliometric analysis, transforming growth factor β, and autotaxin inhibitor-capture the essential aspects of this research domain. This analysis serves as a reference point for future investigations into targeted therapies.

Epidemiology of idiopathic pulmonary fibrosis in central and Western Pennsylvania

BACKGROUND/RATIONALE

Idiopathic Pulmonary Fibrosis (IPF) is a chronic, progressive disease of unknown origin. Establishing the epidemiology of IPF has been challenging due to diagnostic complexity, poor survival, low prevalence, and heterogeneity of ascertainment methodologies.

OBJECTIVES

This research aimed to estimate the rates of IPF in central and western Pennsylvania and to pilot the use of capture recapture (CR) methods to estimate the disease incidence.

METHODS

We identified adults ≥ 30 years old diagnosed with IPF (by ICD-9/10 coding) between 2013 to 2021 from two health systems (UPMC Health System and Penn State Health) participating in the PaTH Clinical Research Network. We extracted information on patients' sex, race, date of birth and 3-digit zip code from electronic health records (EHR). Incidence rate of IPF among Pennsylvania residents was calculated using three case definitions (broad and two restricted) and piloted the use of CR in estimating IPF incidence.

RESULTS

IPF incidence rates were 8.42, 6.95 and 4.4 per 100,000 person-years for the unrestricted (n = 3148), partially restricted (n = 2598) and fully restricted (n = 1661) samples, respectively. Low case overlap between two sites resulted in a highly inflated estimate of IPF incidence, using the CR methodology.

CONCLUSIONS

The rate of IPF in central and western Pennsylvania was similar to previously published statistics. The application of CR to IPF epidemiology could be further investigated in health systems with greater overlap of patients utilizing more than one system.

Long-Term Air Pollution Exposure and Severity of Idiopathic Pulmonary Fibrosis: Data from the Idiopathic Pulmonary Fibrosis Prospective Outcomes (IPF-PRO) Registry

Rationale: Although exposure to air pollution is a known risk factor for adverse pulmonary outcomes, its impact in individuals with idiopathic pulmonary fibrosis (IPF) is less well understood. Objectives: To investigate the effects of long-term exposure to air pollution on disease severity and progression in patients with IPF and to determine whether genomic factors, such as MUC5B promoter polymorphism or telomere length, modify these associations. Methods: We performed analyses at enrollment and after 1 year of follow-up in the IPF-PRO (Idiopathic Pulmonary Fibrosis Prospective Outcomes) Registry, a prospective observational registry that enrolled individuals with IPF at 46 U.S. sites from June 2014 to October 2018. Five-year average pollution exposures (particulate matter ≤2.5 μm in aerodynamic diameter [PM2.5], nitrogen dioxide, ozone) before the enrollment date were estimated at participants' residential addresses with validated national spatiotemporal models. Multivariable regression models estimated associations between pollution exposure and physiologic measurements (forced vital capacity [FVC], diffusing capacity of the lung for carbon monoxide, supplemental oxygen use at rest) and quality-of-life measurements (St. George's Respiratory Questionnaire, EuroQoL, Cough and Sputum Assessment Questionnaire) at enrollment. Cox proportional hazards models estimated associations between pollutants and a composite outcome of death, lung transplant, or >10% absolute decline in FVC percent predicted in the year after enrollment. Models were adjusted for individual-level and spatial confounders, including proxies for disease onset. Gene-environment interactions with MUC5B and telomere length were assessed. Results: Of 835 participants, 94% were non-Hispanic White individuals, 76% were male, and the mean (standard deviation) age was 70 (7.7) years. In fully adjusted analyses, higher PM2.5 exposure was associated with worse quality of life per St. George's Respiratory Questionnaire activity score (3.48 [95% confidence interval (CI), 0.64, 6.32] per 2 μg/m3 PM2.5) and EuroQoL scores (-0.04 [95% CI, -0.06, -0.01] per 2 μg/m3 PM2.5), as well as lower FVC percent predicted and lower diffusing capacity of the lung for carbon monoxide percent predicted at enrollment. Each 3 parts per billion difference in O3 exposure was associated with a 1.57% (95% CI, 0.15, 2.98) higher FVC percent predicted at enrollment, although this effect was attenuated in multipollutant models. There was no association between nitrogen dioxide and enrollment measures or between pollution exposure and 1-year outcomes and no evidence for gene-environment interactions. Conclusions: In the IPF-PRO Registry, long-term exposure to PM2.5 was associated with worse quality of life and lung function at enrollment, but not with short-term disease progression or mortality. There was no evidence of effect modification by interaction of genomic factors with pollution. The reason for the unexpected relationship between O3 exposure and higher FVC is unclear. Clinical trial registered with www.clinicaltrials.gov (NCT01915511).

Advances in idiopathic pulmonary fibrosis diagnosis and treatment

Significant advances have been made in diagnosing and treating idiopathic pulmonary fibrosis (IPF) in the last decade. The incidence and prevalence of IPF are increasing, and morbidity and mortality remain high despite the two Food and Drug Administration (FDA)-approved medications, pirfenidone and nintedanib. Hence, there is an urgent need to develop new diagnostic tools and effective therapeutics to improve early, accurate diagnosis of IPF and halt or reverse the progression of fibrosis with a better safety profile. New diagnostic tools such as transbronchial cryobiopsy and genomic classifier require less tissue and generally have good safety profiles, and they have been increasingly utilized in clinical practice. Advances in artificial intelligence-aided diagnostic software are promising, but challenges remain. Both pirfenidone and nintedanib focus on growth factor-activated pathways to inhibit fibroblast activation. Novel therapies targeting different pathways and cell types (immune and epithelial cells) are being investigated. Biomarker-based personalized medicine approaches are also in clinical trials. This review aims to summarize recent diagnostic and therapeutic development in IPF.

Combined therapy with pirfenidone and nintedanib counteracts fibrotic silicosis in mice

BACKGROUND AND PURPOSE

Pneumoconiosis, especially silicosis, is a prevalent occupational disease with substantial global economic implications and lacks a definitive cure. Both pneumoconiosis and idiopathic pulmonary fibrosis (IPF) are interstitial lung diseases, which share many common physiological characteristics. Because pirfenidone and nintedanib are approved to treat IPF, their potential efficacy as antifibrotic agents in advanced silicosis deserves further exploration. Thus, we aimed to evaluate the individual and combined effects of pirfenidone and nintedanib in treating advanced silicosis mice and elucidate the underlying mechanisms of their therapeutic actions via multiomics.

EXPERIMENTAL APPROACH

We administered monotherapy or combined therapy of pirfenidone and nintedanib, with low and high doses, in silicosis established after 6 weeks and evaluated lung function, inflammatory responses and fibrotic status. Additionally, we employed transcriptomic and metabolomic analyses to uncover the mechanisms underlying different therapeutic strategies.

KEY RESULTS

Both pirfenidone and nintedanib were effective in treating advanced silicosis, with superior outcomes observed in combination therapy. Transcriptomic and metabolomic analyses revealed that pirfenidone and nintedanib primarily exerted their therapeutic effects by modulating immune responses, signalling cascades and metabolic processes involving lipids, nucleotides and carbohydrates. Furthermore, we experimentally validated both monotherapy and combined therapy yielded therapeutic benefits through two common signalling pathways: steroid biosynthesis and purine metabolism.

CONCLUSION AND IMPLICATIONS

In conclusion, pirfenidone and nintedanib, either individually or in combination, demonstrate substantial potential in advanced silicosis. Furthermore, combined therapy outperformed monotherapy, even at low doses. These therapeutic benefits are attributed to their influence on diverse signalling pathways and metabolic processes.

Predictive Value of Serum sIL-2R Levels and Th17/Treg Immune Balance for Disease Progression in Patients With Rheumatoid Arthritis-Associated Interstitial Lung Disease

BACKGROUND

This article analyzed the relationship between serum sIL-2R levels and Th17/Treg immune balance in patients with rheumatoid arthritis-associated interstitial lung disease (RA-ILD) and their prognostic value.

METHODS

RA patients (n = 311) were retrospectively selected for research and then allocated to the RA and RA-ILD groups. Baseline data and 3-year follow-up records of all patients were attained to assess disease progression. Serum sIL-2R levels were examined with ELISA, and Th17 and Treg cell clusters were tested with flow cytometry, followed by the calculation of the Th17/Treg ratio. The correlation of serum sIL-2R with Th17/Treg and related cytokines (IL-17, IL-6, IL-10, and TGF-β1) in RA-ILD patients were analyzed with Spearman's analysis. ROC curves were plotted for analyzing the performance of serum sIL-2R levels and the Th17/Treg ratio for predicting disease progression in RA-ILD patients. A multivariate Cox regression model was developed to screen independent risk factors for disease progression in RA-ILD patients.

RESULTS

RA-ILD patients had elevated serum levels of sIL-2R, Th17 cells, IL-17, and IL-6 and an increased ratio of Th17/Treg, accompanied by a decreased Treg cell population and IL-10 and TGF-β1 levels. Serum sIL-2R levels were correlated positively with IL-17 levels and the Th17/Treg ratio in RA-ILD patients and negatively with IL-10 levels. DAS28 scores, serum sIL-2R levels, and an elevated Th17/Treg ratio were independent risk factors for disease progression in RA-ILD patients, and increased FEV1 and FEV1/FVC were protective factors.

CONCLUSION

Serum sIL-2R levels in conjunction with Th17/Treg immune balance can assist in predicting 3-year disease progression in RA-ILD patients.

FGF21 Signaling Exerts Antifibrotic Properties during Pulmonary Fibrosis

Rationale: Idiopathic pulmonary fibrosis (IPF) is a lethal disease with limited therapeutic options. FGF21 (fibroblast growth factor 21), an endocrine fibroblast growth factor that acts through the FGFR1 (fibroblast growth factor receptor 1)/KLB (β-Klotho) pathway, mitigates liver fibrosis. Objectives: We hypothesized that FGF21 could exert antifibrotic properties in the lung. Methods: The concentrations of FGF21 and KLB in the plasma of patients with IPF and control subjects were assessed. Pulmonary fibrosis development was assessed in Fgf21-deficient mice compared with wild-type littermates, at Day 14 (D14) after the intratracheal injection of bleomycin. We determined the effect of repeated subcutaneous injections of a PEGylated FGF21 analog at D7, D10, D14, and D17 after bleomycin on the development of pulmonary fibrosis. Mice were killed at D21. The effects of FGF21, alone or with KLB, on apoptosis in murine lung epithelial 15 cells and on the phenotype of human lung fibroblasts were assessed in vitro. Measurements and Main Results: In the plasma of patients with IPF, FGF21 concentrations were increased, while KLB concentrations were decreased. Fgf21-deficient mice showed increased sensitivity to bleomycin in comparison with their wild-type littermates. Treatment with PEGylated FGF21 mitigated lung fibrogenesis, as evidenced by a lower injury score and decreased fibrosis markers and profibrotic mediator expression compared with the control group receiving the diluent. In murine lung epithelial 15 cells, stimulation with FGF21 and KLB inhibited apoptosis, through the decrease of BAX and BIM. Fibroblastic phenotype remained unaltered. Conclusions: Our data indicate a possible antifibrotic effect of FGF21 in the lung achieved through the inhibition of alveolar type 2 cell apoptosis.

Non-Pharmacological Management of Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a relatively common progressive fibrotic interstitial lung disease associated with significant morbidity and mortality. The available medications for IPF only slow down the disease process, with lung transplantation the only option for a cure. Non-pharmacological therapies are significant adjuncts that can improve symptom burden and quality of life with minimal or no side effects. Supplemental oxygen can improve exercise capacity and the sensation of dyspnea in a significant portion of patients with resting or exertional hypoxemia and has been supported by several professional societies. Pulmonary rehabilitation is a comprehensive program that includes education and therapeutic exercises to improve patient stamina and strength. It is one of the few interventions that have been shown to produce a meaningful increase in a patient's exercise capacity, but its wide adoption is limited by availability, especially in rural areas. Sleep optimization with supplemental oxygen and positive airway pressure therapy should actively be investigated for all patients diagnosed with IPF. Although gastroesophageal reflux control with non-pharmacological means is still controversial as an intervention to reduce the rate of lung function decline, it can help control reflux symptoms and improve cough intensity. IPF patients should be educated on the importance of balanced nutrition and the potential benefits of screening for lung transplantation. Palliative medicine can help with symptom control and should be considered for all patients regardless severity, but especially in those in the later stages of disease.

Pathophysiology of small airways in idiopathic pulmonary fibrosis (IPF): the silent zone

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease characterized by distorted alveolar structure and reduced lung compliance, and impaired ventilation-perfusion. Small airway disease (SAD) is  often termed a 'quietzone' due to its asymptomatic nature. Around 30-40% of IPF patients exhibit SAD, which is associated with worse prognosis, higher fibrosis and emphysema scores, and elevated mortality risk. We used PubMed and Google Scholar for literature search.

AREAS COVERED

This review explores the pathophysiology of small airways in IPF, focusing on 1. Risk factors, including age, gender, smoking and occupational dust exposure, and ozone. 2. Diagnostic challenges: SAD is difficult to detect through traditional spirometry or high-resolution computed tomography  imaging due to resolution limitations.  3. Early physiological changes of small airways include airway wall thickening, lumen distortion, and reduced terminal bronchioles, preceding microscopic fibrosis, occurs in the early process of IPF. 4. Pathological mechanisms: The review examines the underlying mechanisms driving small airway disease in IPF.

EXPERT OPINION

A comprehensive approach is essential to improve the understanding and management of SAD in IPF. Priorities include identifying therapeutic targets, advanced imaging and functional assessments. Forced oscillation technique should be introduced for early detection for small airway abnormalities in IPF.

Beyond Tumors: The Pivotal Role of TRIM Proteins in Chronic Non-Tumor Lung Diseases

While TRIM proteins are extensively studied in the context of lung tumors, their roles in non-tumor chronic lung diseases remain underexplored. This review delves into the emerging significance of TRIM family proteins in the pathogenesis of idiopathic pulmonary fibrosis (IPF), asthma, chronic obstructive pulmonary disease (COPD), and pulmonary hypertension (PH). TRIM proteins modulate key pathological processes, including inflammation, fibrosis, and cellular remodeling, contributing to disease progression. We highlight their potential as biomarkers and therapeutic targets, offering promising avenues for drug development in these debilitating respiratory disorders. However, the translation of these findings into clinical applications faces significant challenges. These include the dual functional nature of TRIM proteins, their context-dependent roles, the complexity of their downstream signaling networks, and the limitations of current therapeutic strategies in achieving tissue-specific targeting with minimal off-target effects. Addressing these challenges will require innovative approaches and interdisciplinary efforts to unlock the therapeutic potential of TRIM proteins in non-tumor chronic lung diseases.

The effectiveness and risks of Treating people with Idiopathic Pulmonary fibrosis with the Addition of Lansoprazole (TIPAL): study protocol for a randomised placebo-controlled multicentre clinical trial

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive fibrotic lung disease frequently complicated by gastro-oesophageal reflux disease. Although several observational studies and a pilot study have investigated the role of proton pump inhibitors (PPIs) in IPF, their efficacy is unknown and there is much debate in international IPF guidelines on their use. We aim to undertake an adequately powered double-blind placebo-controlled randomised multicentre clinical trial to assess the change in forced vital capacity (FVC), cough and other important patient-reported outcomes, following 12-month therapy with PPIs in people with IPF.

METHODS AND ANALYSIS

A total of 298 patients with IPF diagnosed by a multidisciplinary team according to international guidelines who are not receiving PPIs will be enrolled. Patients are randomised equally to receive two capsules of lansoprazole or two placebo capsules, two times per day for 12 months. The primary outcome for the trial is change in FVC, measured at home, between the first week and last week of the study period. Secondary assessments include cough frequency (in a subgroup) measured using the VitaloJAK cough monitor, the King's Brief Interstitial Lung Disease questionnaire, the Raghu Scale for Pulmonary Fibrosis, Medical Research Council dyspnoea score, EQ-5D-5L, Leicester Cough Questionnaire, modified DeMeester reflux symptoms questionnaire and opportunistically captured routine lung function measurements. High-resolution CT scoring will be undertaken in a subgroup. The trial is designed to determine whether treating people with IPF with lansoprazole will reduce the reduction in FVC over a year. The COVID-19 pandemic required the study to be undertaken as a remote trial.

ETHICS AND DISSEMINATION

This study received ethical approval from the East of England Cambridgeshire and Hertfordshire Research Ethics Committee (reference 20/EE/0043; integrated research application system number 269050). Trial results will be published in a peer-reviewed journal upon completion.

TRIAL REGISTRATION NUMBER

ISRCTN13526307; ClinicalTrials.gov NCT04965298.

Real-World Safety, Tolerability and Effectiveness of Nintedanib in Patients with Idiopathic Pulmonary Fibrosis: Final Report of Post-marketing Surveillance in Japan

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrotic interstitial pneumonia, which is characterised by progressive worsening of dyspnoea and lung function. Nintedanib treatment is recommended to slow IPF disease progression. The aim of this post-marketing surveillance (PMS) study was to evaluate the safety and effectiveness of nintedanib over 24 months in patients with IPF in a real-world setting in Japan.

METHODS

This prospective, non-interventional, all-case PMS study of nintedanib included Japanese patients with IPF who started nintedanib between 7 October 2015 and 2 May 2023. The primary outcome was to determine the proportion of patients with adverse drug reactions (ADRs), and the secondary outcome was the adjusted absolute change from baseline in forced vital capacity (FVC) at 24 months.

RESULTS

In total, 5717 patients from 1013 institutions were included in the safety analysis (mean ± standard deviation age 71.7 ± 8.1 years, 78.1% male, 70.8% current or former smokers). Most patients (83.9%) had initiated nintedanib at a dose of 150 mg capsules twice daily. At 24 months, 2841 patients (64.8%) had discontinued nintedanib, mainly due to adverse events (44.0%), ADRs (24.1%) or insufficient effectiveness (5.7%). The most common ADRs were diarrhoea (35.5%), hepatic function abnormal (14.4%), decreased appetite (9.9%), liver disorders (7.8%) and nausea (5.8%). The adjusted absolute mean change in FVC from baseline to 24 months was - 212.3 mL (95% confidence interval - 235.3, - 189.3).

CONCLUSION

This is the largest prospective study to investigate patients with IPF who were treated with nintedanib. The safety and effectiveness of nintedanib treatment in this real-world setting of Japanese patients with IPF was similar to that reported in previous studies. Nintedanib effectively slowed the progression of IPF. No new safety concerns were identified, and the need for appropriate management of hepatic disorders and diarrhoea (as per the approved product information) was confirmed.

STUDY REGISTRATION

ClinicalTrials.gov (NCT02607722)/European Union electronic register of Post-Authorisation Studies (EUPAS10891).

Single Cell RNA-Seq Identifies Cell Subpopulations Contributing to Idiopathic Pulmonary Fibrosis in Humans

The cell populations, particularly subpopulations, involved in the onset and progression of idiopathic pulmonary fibrosis (IPF) remain incompletely understood. This study employed single-cell RNA-seq to identify cell populations and subpopulations with significantly altered proportions in the lungs of patients with IPF. In IPF lungs, endothelial cell proportions were significantly increased, while alveolar epithelial cell proportions were markedly decreased. Among the three identified fibroblast subpopulations, the proportion of myofibroblasts was significantly increased, while the proportions of the other two fibroblast subtypes were reduced. Similarly, within the three macrophage subpopulations, the macrophage_SPP1 subpopulation, localised to fibroblastic foci, showed a significant increase in proportion, while the alveolar macrophage subpopulation was significantly reduced. Trajectory analysis revealed that fibroblasts in IPF lungs could differentiate into myofibroblasts, and alveolar macrophages could transition into the macrophage_SPP1 subpopulation. Among T-cell subpopulations, only the CD4 T_FOXP3 subpopulation exhibited a significant change, whereas all four B-cell subpopulations showed significant proportional shifts. These findings provide a comprehensive view of the cellular alterations contributing to IPF pathogenesis. Extensive interactions among various cell populations and subpopulations were identified. The proportions of various cell populations and subpopulations in IPF lungs, including endothelial cells, fibroblasts, macrophages and B cells, were significantly altered. Further in-depth investigation into the roles of cell subpopulations with significantly altered proportions in the onset and progression of IPF will provide valuable insights into the pathological mechanisms underlying the disease. This understanding could facilitate the development of novel therapeutic strategies and medications for IPF treatment.

Commonly prescribed medications and risk of pneumonia and all-cause mortality in people with idiopathic pulmonary fibrosis: a UK population-based cohort study

BACKGROUND

A growing body of evidence suggests that prolonged use of inhaled corticosteroids (ICS) and proton pump inhibitors (PPIs) is associated with increased risks of pneumonia. A substantial proportion of people with idiopathic pulmonary fibrosis (IPF) are prescribed PPIs or ICS to treat common comorbidities, giving rise to concerns that use of these medications may be associated with potential harms in this patient population.

METHODS

We used UK Clinical Practice Research Datalink (CPRD) Aurum primary care data linked to national mortality and hospital admissions data to create a cohort of people diagnosed with IPF on or after 1 January 2010. Patients were assigned to one of three exposure categories according to their prescribing history in the 12 months prior to IPF diagnosis as follows: "regular" users (≥ 4 prescriptions), "irregular" users (1-3 prescriptions) and "non-users" (no prescriptions). We explored the association between PPI/ICS prescription and pneumonia hospitalisation and all-cause mortality using multinomial Cox regression models.

RESULTS

A total of 17,105 people met our study inclusion criteria; 62.6% were male and 15.9% were current smokers. Median age at IPF diagnosis was 76.7 years (IQR: 69.6-82.7). 19.9% were regularly prescribed PPIs, and 16.0% ICS, prior to IPF diagnosis. Regular prescribing of PPIs and ICS was positively associated with hospitalisation for pneumonia; the adjusted HR for pneumonia hospitalisation comparing regular PPI users with non-users was 1.14 (95%CI: 1.04-1.24); for regular ICS users the corresponding HR was 1.40 (95%CI: 1.25-1.55). We also observed a small increased risk for all-cause mortality in the "regular ICS user" group compared with the "non-user" control group (HRadj = 1.19, 1.06-1.33). We found no evidence of an association between PPI prescribing and all-cause mortality.

CONCLUSION

Prolonged prescription of medications used to treat common comorbidities in IPF may be associated with increased risks for severe respiratory infections. These findings point to a need to adopt an adequate risk-benefit balance approach to the prescribing of ICS-containing inhalers and PPIs in people with IPF without evidence of comorbidities, especially older patients and/or those with more advanced disease in whom respiratory infections are more likely to result in poorer outcomes.

Jinbei oral liquid for idiopathic pulmonary fibrosis: a randomized placebo-controlled trial

The traditional Chinese medicine compound preparation known as Jinbei Oral Liquid (JBOL) consists of 12 herbs, including Astragalus membranaceus (Fisch.) Bge, Codonopsis pilosula (Franch.) Nannf, et al. Having been used for over 30 years in the treatment of pulmonary diseases, JBOL was evaluated in this study in order to assess its effect on idiopathic pulmonary fibrosis as well as its safety (ChiCTR2000035351, Chictr.org.cn.09/08/2020). A double-blind, multicenter, randomized, proof-of-concept trial was conducted to assess the efficacy of oral JBOL 40 ml and Corbrin Capsules 1 g compared to a placebo and Corbrin Capsules in patients with idiopathic pulmonary fibrosis (IPF). Over a 26-week period, patients received the active treatment or placebo three times daily, in a 1:1 ratio. This clinical study uses a randomized method, with a cycle of every 4 patients. TCM doctors at or above the deputy director level of the research center conduct TCM dialectics on IPF patients. To assess efficacy, over the duration of the trial, we measured serial changes in a composite indicator encompassing time to first acute exacerbation of IPF (first hospitalization or death due to respiratory cause), total lung capacity (TLC) (mL), predicted forced vital capacity (FVC%), forced vital capacity (FVC) (mL), predicted diffusing capacity of the lungs for carbon monoxide (predicted DLco%), 6-minute walk distance (6MWD), St. George's Respiratory Questionnaire (SGRQ) total score, and arterial oxygen partial pressure (PaO2) from baseline to week 26 versus placebo. A total of 103 patients were screened, and 72 received the study medication. Of these, 68 patients were included in the analysis set, with 34 receiving JBOL and 34 receiving a placebo. After 26 weeks, a statistically significant reduction in total lung capacity (TLC) was observed for the JBOL group, with a change of 136 mL compared to -523 mL for the placebo group (difference 659 mL, 95% CI -1215 to -104 mL, p = 0.02). The study found that the change in FVC% predicted was - 1.48% and - 3.58% for the JBOL and placebo groups, respectively (difference of 2.10%, 95% CI -7.13 to 2.93, p = 0.41). Additionally the differences between the two groups in changes in FVC (mL), DLCO % predicted, PaO2 (mmHg) measures were - 67 mL (95% CI -238 to 104), -7.74% (95% CI -17.26 to 1.79), and - 3.57 mmHg (95% CI -10.02 to 2.87), respectively. Treatment with JBOL compared to placebo resulted in sequential changes in acute exacerbation, with no significant difference in SGRQ scores. It was not found that there was a statistically significant difference between the JBOL and placebo groups in TEAE reporting and serious TEAE reporting. Compared to the placebo group, there was a statistically significant reduction (p < 0.021) in TLC (mL) after 26 weeks for JBOL. The rates of FVC % predicted, FVC, DLCO % predicted, and PaO2 in the group treatment with JBOL were numerically lower than those in the placebo treatment group, although these differences did not reach statistical significance. JBOL exhibited comparable safety to placebo. This study has preliminarily shown the efficacy and safety of JBOL for IPF, but this is an exploratory clinical trial, more patient-involved studies should be needed in the near future.Trial registration: Chictr.org.cn ChiCTR2000035351; the trial was prospective clinical studies registered on August 9, 2020.

The histone demethylase KDM6B links obstructive sleep apnea to idiopathic pulmonary fibrosis

Obstructive sleep apnea (OSA) is increasingly recognized for its link to idiopathic pulmonary fibrosis (IPF), though the underlying mechanisms remain poorly understood. Histone lysine demethylase 6B (KDM6B) may either prevent or promote organ fibrosis, but its specific role in IPF is yet to be clarified. This study aimed to investigate the function and mechanisms of KDM6B in IPF and the exacerbating effects of OSA. We assessed KDM6B levels in lung tissues from IPF patients, IPF mouse models, and a dual-hit model combining OSA-associated intermittent hypoxia (IH) with bleomycin (BLM) or TGF-β1. We evaluated pulmonary fibrosis, myofibroblast activation, and oxidative stress. KDM6B levels were elevated in lung tissues from IPF patients and BLM-treated mice, as well as in TGF-β1-stimulated myofibroblasts. Importantly, IH significantly worsened BLM-induced pulmonary fibrosis and TGF-β1-induced myofibroblast activation, further amplifying KDM6B expression both in vivo and in vitro. Inhibition of KDM6B reduced pulmonary fibrosis and decreased fibroblast activation and migration in IPF and dual-hit models. Mechanistically, KDM6B inhibition led to decreased NOX4 expression and reduced oxidative stress. KDM6B plays a critical role in promoting pulmonary fibrosis and mediating the exacerbating effects of OSA on this condition. Our findings identify KDM6B as a novel potential therapeutic target for IPF.

Human Umbilical Cord-Mesenchymal Stem Cells Combined With Low Dosage Nintedanib Rather Than Using Alone Mitigates Pulmonary Fibrosis in Mice

Pulmonary fibrosis (PF) is a lethal pathological change of fibrotic interstitial lung diseases (ILDs) with abundant fibroblasts proliferation after severely or continually alveolar epithelial cells (AECs) injury. Barely therapies are helpful for PF. Here we use bleomycin intratracheally injection to model PF with or without human umbilical cord-mesenchymal stem cells (hUC-MSCs) and/or nintedanib intervention. RNA-Seq followed with real-time PCR and western blot were used to find out the specific possible mechanisms of the effects of hUC-MSC and nintedanib on PF. Immunostaining, cell counting kit-8 (CCK-8), and 5-bromo-2'-deoxyuridine (BrdU) incorporation assay were used to detect the cell proliferation in vivo or in vitro separately. We found that hUC-MSCs alone had prophylactic, but not therapeutic effects on bleomycin induced mouse PF. Nevertheless, the combination therapy of hUC-MSCs and low-dose nintedanib significantly improved survival and reversed lung fibrosis in PF model mice. The factors secreted by hUC-MSCs have promotional effects on the proliferation both of fibroblasts and AECs. Nintedanib could hamper the facilitation of fibroblasts caused by hUC-MSCs without influence on AECs proliferation, which might be related with the inhibition on FGFR, PDGFR, and VEGFR activities. Our study indicated that the combination therapy of hUC-MSCs and nintedanib should be a promising strategy for PF.

Traditional Chinese Medicine Ion Introduction Therapy Reduces the Incidence of Acute Exacerbation of Idiopathic Pulmonary Fibrosis: A Prospective Cohort Study

Objective

To evaluate the effectiveness and safety of traditional Chinese medicine (TCM) ion introduction therapy in the treatment of patients with acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF).

Methods

This study adopts a prospective cohort study design, with 60 AE-IPF patients as the research subjects. Divided into an exposed group and a non exposed group, with 30 cases in each group, based on the frequency of TCM ion introduction treatment as the exposure factor. Follow-up for 1 year to observe the acute exacerbation of the patient. The main indicator is the annual incidence of acute exacerbation, and the secondary indicators are hospitalization time, readmission rate, time to first acute exacerbation, mortality rate, all-cause mortality rate, inflammatory indicators, quality of life, etc.

Results

51 patients completed a one-year clinical observation, including 27 in the exposed group and 24 in the non exposed group. Compared to the non exposed group, significant differences were observed in the annual incidence of acute exacerbation [incidence rate ratios (IRR) = 0.556, 95% CI: 0.315, 0.980; P = 0.035] and hospitalization time (P = 0.040), readmission rate (IRR = 0.533, 95% CI: 0.288, 0.988; P = 0.037), time to first acute exacerbation (P = 0.045), and quality of life (P < 0.05). However, there was no statistically significant difference in mortality rate and all-cause mortality rate between the two groups (P > 0.05).

Conclusion

Compared to the non exposed group, TCM ion introduction can reduce the annual incidence of acute exacerbation of IPF patients. Hospitalization time, readmission rate, time to first acute exacerbation, quality of life improved, but mortality rate and all-cause mortality rate did not improve.

Health-related quality of life and health state utility value in idiopathic pulmonary fibrosis: a systematic review and meta-analysis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is associated with high mortality, heavy economic burden, limited treatment options and poor prognosis, and seriously affects the health-related quality of life (HRQoL) and life expectancy of patients. This systematic review and meta-analysis of HRQoL and health state utility value (HSUV) in IPF patients and the instruments used in this assessment aimed to provide information sources and data support for the future research on IPF HRQoL and HSUV.

METHODS

We searched the PubMed, EMBASE, Web of Science and Cochrane Library databases for studies reporting the HRQoL or HSUV of IPF patients, with the retrieval time from the establishment of each database to April 2024. After two researchers independently screened the literature, extracted the data, and evaluated the risk of bias in the included studies, pooled analysis was performed on the measurement tools adopted in more than two studies. Subgroup analysis was employed to explore the source of heterogeneity, and sensitivity analysis was used to assess the robustness of the results. Funnel-plot directed evaluation combined with Egger's test quantitative evaluation was conducted to detect publication bias.

RESULTS

Sixty-nine studies were ultimately included, covering eighteen measurement tools. The literature quality was generally excellent. The St. George's Respiratory Questionnaire (SGRQ), EuroQoL Five Dimensions Questionnaire (EQ-5D), Short Form-36 (SF-36) and the King's Brief Interstitial Lung Disease (KBILD) were the most common instruments, among which the EQ-5D included the HSUV and the visual analog scale (VAS). The results of the meta-analysis revealed that the pooled SGRQ total score was 45.28 (95% confidence interval [CI] 41.10-49.47), the mean EQ-5D utility score was 0.75 (95% CI: 0.72-0.79), the total EQ-5D VAS score was 66.88 (95% CI: 63.75-70.01), and the pooled SF-36 physical component summary (PCS) and mental component summary (MCS) score were 36.70 (95% CI: 32.98-40.41) and 48.99 (95% CI: 47.44-50.55), respectively. The total KBILD score was 58.31 (95% CI: 55.43-61.19), the IPF specific version of the SGRQ (SGRQ-I) was 40.38 (95% CI: 28.81-51.96) and the Leicester Cough Questionnaire (LCQ) score was 16.09 (95% CI: 15.45-16.74). The pooled result of the University of California San Diego Shortness of Breath Questionnaire (USCD-SOBQ) was 45.05 (95% CI: 41.56-48.55). The results of other instruments, such as the tool to assess quality of life in IPF (ATAQ-IPF), the World Health Organization Quality of Life assessment 100 (WHOQoL-100) and the 12-item short-form health survey (SF-12) were similar to those of the above measurement tools. Regretfully, subgroup analyses did not identify the source of heterogeneity, but sensitivity analyses demonstrated robustness of our results. Except for the SGRQ total, our results showed little possibility of publication bias.

CONCLUSIONS

HRQoL in IPF patients is generally poor, and all domains are severely affected. With the aggravation of disease, HRQoL and HSUV shows a relatively downward trend, and income level is also an important factor affecting HRQoL and HSUV. At present, the published studies on IPF HRQoL and HSUV have applied many measurement tools with high interstudy heterogeneity, and future research on the optimal disease measurement tools should be strengthened. Our study provides high-quality comprehensive evidence for IPF HRQoL and HSUV, which can be used to guide clinical and economic evaluation in the future.

Common biomarkers of idiopathic pulmonary fibrosis and systemic sclerosis based on WGCNA and machine learning

Interstitial lung disease (ILD) is known to be a major complication of systemic sclerosis (SSc) and a leading cause of death in SSc patients. As the most common type of ILD, the pathogenesis of idiopathic pulmonary fibrosis (IPF) has not been fully elucidated. In this study, weighted correlation network analysis (WGCNA), protein‒protein interaction, Kaplan-Meier curve, univariate Cox analysis and machine learning methods were used on datasets from the Gene Expression Omnibus database. CCL2 was identified as a common characteristic gene of IPF and SSc. The genes associated with CCL2 expression in both diseases were enriched mainly in chemokine-related pathways and lipid metabolism-related pathways according to Gene Set Enrichment Analysis. Single-cell RNA sequencing (sc-RNAseq) revealed a significant difference in CCL2 expression in alveolar epithelial type 1/2 cells, mast cells, ciliated cells, club cells, fibroblasts, M1/M2 macrophages, monocytes and plasma cells between IPF patients and healthy donors. Statistical analyses revealed that CCL2 was negatively correlated with lung function in IPF patients and decreased after mycophenolate mofetil (MMF) treatment in SSc patients. Finally, we identified CCL2 as a common biomarker from IPF and SSc, revealing the common mechanism of these two diseases and providing clues for the study of the treatment and mechanism of these two diseases.

Potential of phosphodiesterase 4B inhibition in the treatment of progressive pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is often regarded as the archetypal progressive fibrosing interstitial lung disease (ILD). The term "progressive pulmonary fibrosis" (PPF) generally describes progressive lung fibrosis in an individual with an ILD other than IPF. Both IPF and PPF are associated with loss of lung function, worsening dyspnea and quality of life, and premature death. Current treatments slow the decline in lung function but have side effects that may deter the initiation or continuation of treatment. There remains a high unmet need for additional therapies that can be used alone or in combination with current therapies to preserve lung function in patients with IPF and PPF. Phosphodiesterase-4 (PDE4) is an enzyme involved in the regulation of inflammatory processes. Pre-clinical studies have shown that preferential inhibition of PDE4B has anti-inflammatory and antifibrotic effects and a lower potential for gastrointestinal adverse events than pan-PDE4 inhibition. The preferential PDE4B inhibitor nerandomilast demonstrated efficacy in preserving lung function in a phase II trial in patients with IPF and is under investigation in phase III trials as a treatment for IPF and PPF.

Optimising pirfenidone dosage regimens in idiopathic pulmonary fibrosis: towards a guide for personalised treatment

Idiopathic Pulmonary Fibrosis (IPF) is a chronic respiratory disorder for which pirfenidone is the recommended first-line anti-fibrotic treatment. While pirfenidone has demonstrated efficacy in slowing the progression of IPF, its use is associated with several challenges and unresolved issues that impact patient outcomes. Pirfenidone administration can result in gastrointestinal side effects, photosensitivity reactions, and significant drug interactions, particularly in patients with hepatic impairment. For those who experience intolerable side effects, dose reductions or temporary discontinuations are frequently employed. However, there is limited data on the efficacy of reduced doses, creating uncertainty about the balance between tolerability and therapeutic benefit.The aim of this study is to evaluate the currently proposed dosage adjustments and to develop new dosage regimens tailored to the needs of patients. Simulations were conducted to explore pirfenidone pharmacokinetics under various challenging conditions, including dose titration, withdrawal, retitration, moderate and severe hepatic impairment, co-administration of moderate (e.g. omeprazole) and strong (e.g. smoking) inducers of the CYP1A2 enzyme, gastrointestinal adverse events, and photosensitivity reactions.Simulations led to specific recommendations for physicians regarding dosage regimens in each condition. The recommended dosage adjustments are designed to maintain concentrations within acceptable levels, ensuring both safe and effective treatment.

Orderly Regulation of Macrophages and Fibroblasts by Axl in Bleomycin-Induced Pulmonary Fibrosis in Mice

Pulmonary fibrosis is a pathological manifestation that occurs upon lung injury and subsequence aberrant repair with poor prognosis. However, current treatment is limited and does not distinguish different disease stages. Here, we aimed to study the differential functions of Axl, a receptor tyrosine kinase expressing on both macrophages and fibroblasts, in the whole course of pulmonary fibrosis. We used mice with Axl total knockout, conditionally knockout in macrophages or fibroblasts, or treating with Axl inhibitors in inflammation or fibrosis stages to examine the effect of temporary dysfunction of Axl on bleomycin (BLM)-induced pulmonary fibrosis. Primary bone marrow-derived monocytes and primary fibroblasts from mice were used for cell-type-specific studies. Lung tissue and plasma samples were collected from idiopathic pulmonary fibrosis (IPF) patients and healthy controls to assess the Axl levels. We found that Axl inhibited the M1 polarisation of macrophages; inhibition of Axl during acute phase exacerbated inflammatory response and subsequent pulmonary fibrosis. On the other hand, Axl promoted the proliferation and invasion of the fibroblasts, partially by accelerating the focal adhesion turnover; inhibiting Axl during the fibrotic phase significantly alleviated pulmonary fibrosis. Consistently, phosphorylated Axl levels increased in fibrotic foci in the lung sample of IPF patients. In contrast, the soluble Axl (sAxl) level decreased in their plasma as compared to healthy controls. These results indicate that Axl may sequentially and differentially regulate macrophages and fibroblasts in acute and fibrosis phases, implying the necessity of a stage-specific treatment for pulmonary fibrosis. In addition, the activated Axl on fibroblasts may be reflected by the lowered plasma sAxl level, which may act as a biomarker for IPF. Trial Registration: ClinicalTrials.gov identifier: NCT03730337.

Prognostic value of the 6-min walk test derived attributes in patients with idiopathic pulmonary fibrosis

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) is a fatal progressive fibrosing lung disease. A decreased 6-min walk distance (6MWD) and exercise-induced oxygen desaturation measured during the 6-min walk test (6MWT), are known predictors of mortality in patients with IPF. However, the use of antifibrotic drugs showed a survival benefit in IPF. Therefore, this study aimed to evaluate to what extend 6MWT-derived attributes are associated with two-year survival when antifibrotic drugs were introduced as part of standard IPF-care.

METHODS

This real-world data-study included patients with IPF with a 6MWT between 2015 and 2020, and used composite outcome: mortality or lung transplantation within 2 years of follow-up. Data were collected systematically, including demographics, pulmonary function tests, comorbidities, medications and 6MWT-derived attributes. The prediction attributes of 6MWT were studied with a Cox Proportional-Hazards model and Kaplan-Meier survival curves. The best discriminating attribute to predict mortality was added to the prediction model Gender-Age-Physiology (GAP).

RESULTS

In 216 patients, 2-year transplant-free survival cut-off points were identified for the 6MWD (≥413 m), 6MWD %predicted (≥83 %), SpO2-nadir (≥86 %) and distance-saturation-product (≥374 m%), with the best discriminative value for SpO2-nadir (area under the curve: 0.761). 2-Year survival percentage of patients with SpO2-nadir below or above threshold (86 %) was 37.1 % and 80.0 %, respectively. Exercise-induced oxygen desaturation added to the GAP model showed an improvement in its predictive power.

CONCLUSION

Patients with IPF who have an exercise-induced oxygen desaturation have worse prognosis. Addition of SpO2-nadir to the GAP model seems promising for use in clinical care of IPF patients.

Identifying outcome domains to establish a core outcome set for progressive pulmonary fibrosis: a scoping review

INTRODUCTION

People with idiopathic pulmonary fibrosis (IPF) and other forms of progressive pulmonary fibrosis (PPF) have a high symptom burden and a poor health-related quality of life (HRQoL). Despite efforts to offer specialised treatment, clinical care for these patients remains suboptimal and several nonmedical needs remain unaddressed. Developing a core outcome set (COS) can help to identify a minimum set of agreed-upon outcomes that should be measured and acted-upon in clinical care.

AIM

As a first step towards developing a COS for IPF/PPF, we aimed to identify outcome domains investigated in IPF/PPF research.

METHODS

Conducted within the COCOS-IPF (Co-designing a Core Outcome Set for and with patients with IPF) project, this scoping review follows Joanna Briggs Institute methodology and PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines to search PubMed, Embase and Web of Science for quantitative, qualitative and mixed-methods papers. We extracted each paper's outcomes verbatim and classified them using the COMET (Core Outcome Measures in Effectiveness Trials) taxonomy. Then, the research team structured outcomes or concepts with similar meanings inductively into outcome domains.

RESULTS

We included 428 papers, extracting 1685 outcomes. Most outcomes (n=1340) were identified in quantitative sources, which we could classify in 64 outcome domains, with the main domains being "all-cause survival" (n=237), "lung function" (n=164) and "exercise capacity" (n=99). Qualitative sources identified 51 outcome domains, with the most frequent being "capability to do activities you enjoy" (n=31), "anxiety, worry and fear" (n=26) and "dealing with disease progression" (n=25).

CONCLUSIONS

The identified outcomes, spanning diverse domains, highlight the complexity of patient experiences and can form the basis to develop a COS for IPF/PPF clinical care, as well as future research.

Antifibrotic therapy combined with pulmonary vasodilator therapy may improve survival in patients with pulmonary fibrosis and pulmonary hypertension: a retrospective cohort study

BACKGROUND

Pulmonary fibrosis is a severe, progressive form of interstitial lung disease associated with increased morbidity and mortality. Pulmonary hypertension often accompanies severe pulmonary fibrosis and is also associated with worse outcomes. Antifibrotic therapy and pulmonary vasodilator therapy have demonstrated clinical benefits in pulmonary fibrosis and pulmonary hypertension, respectively. However, the benefit of combined antifibrotic and pulmonary vasodilator therapy in patients with both pulmonary fibrosis and pulmonary hypertension is less established.

OBJECTIVES

We aimed to determine the effectiveness of a combination pulmonary vasodilator and antifibrotic therapy with regard to transplant-free survival and six-minute walk distance improvement in patients with pulmonary fibrosis and pulmonary hypertension.

DESIGN

This was a retrospective cohort study of patients with pulmonary fibrosis (idiopathic pulmonary fibrosis, combined pulmonary fibrosis and emphysema, and other fibrotic interstitial lung disease) and pulmonary hypertension diagnosed via right heart catheterization. Patients received antifibrotic therapy with or without pulmonary vasodilator therapy.

METHODS

Patients who received combination antifibrotic therapy and pulmonary vasodilator therapy were compared to those prescribed antifibrotic therapy alone. Transplant-free survival and change in six-minute walk distance were compared between the two groups. Multivariable Cox regression was performed to determine predictors of transplant-free survival.

RESULTS

Patients who received antifibrotic and pulmonary vasodilator therapy had significantly improved transplant-free survival (log rank p = 0.001). Treatment with antifibrotic and pulmonary vasodilator therapy was significantly and independently associated with reduced risk of death or lung transplantation (HR 0.24, 95% CI 0.06-0.93, p = 0.04). These patients had worse pulmonary hemodynamics than those receiving antifibrotic therapy alone.

CONCLUSION

We found a potential survival benefit when pulmonary vasodilator therapy was given in combination with antifibrotic therapy in patients with pulmonary fibrosis and pulmonary hypertension. This may be reflective of a pulmonary vascular phenotype among those with pulmonary fibrosis and pulmonary hypertension. Further trials are needed to better elucidate which patients benefit from combination therapy.

Otilonium bromide ameliorates pulmonary fibrosis in mice through activating phosphatase PPM1A

Pulmonary fibrosis (PF) is a chronic, progressive and irreversible interstitial lung disease characterized by unremitting pulmonary myofibroblasts activation, extracellular matrix (ECM) deposition and inflammatory recruitment. PF has no curable medication yet. In this study we investigated the molecular pathogenesis and potential therapeutic targets of PF and discovered drug lead compounds for PF therapy. A murine PF model was established in mice by intratracheal instillation of bleomycin (BLM, 5 mg/kg). We showed that the protein level of pulmonary protein phosphatase magnesium-dependent 1A (PPM1A, also known as PP2Cα) was significantly downregulated in PF patients and BLM-induced PF mice. We demonstrated that TRIM47 promoted ubiquitination and decreased PPM1A protein in PF progression. By screening the lab in-house compound library, we discovered otilonium bromide (OB, clinically used for treating irritable bowel syndrome) as a PPM1A enzymatic activator with an EC50 value of 4.23 μM. Treatment with OB (2.5, 5 mg·kg-1·d-1, i.p., for 20 days) significantly ameliorated PF-like pathology in mice. We constructed PF mice with PPM1A-specific knockdown in the lung tissues, and determined that by targeting PPM1A, OB treatment suppressed ECM deposition through TGF-β/SMAD3 pathway in fibroblasts, repressed inflammatory responses through NF-κB/NLRP3 pathway in alveolar epithelial cells, and blunted the crosstalk between inflammation in alveolar epithelial cells and ECM deposition in fibroblasts. Together, our results demonstrate that pulmonary PPM1A activation is a promising therapeutic strategy for PF and highlighted the potential of OB in the treatment of the disease.

Overlapping Systemic Proteins in COVID-19 and Lung Fibrosis Associated with Tissue Remodeling and Inflammation

Background/Objectives: A novel patient group with chronic pulmonary fibrosis is emerging post COVID-19. To identify patients at risk of developing post-COVID-19 lung fibrosis, we here aimed to identify systemic proteins that overlap with fibrotic markers identified in patients with idiopathic pulmonary fibrosis (IPF) and may predict COVID-19-induced lung fibrosis. Methods: Ninety-two proteins were measured in plasma samples from hospitalized patients with moderate and severe COVID-19 in Sweden, before the introduction of the vaccination program, as well as from healthy individuals. These measurements were conducted using proximity extension assay (PEA) technology with a panel including inflammatory and remodeling proteins. Histopathological alterations were evaluated in explanted lung tissue. Results: Connecting to IPF pathology, several proteins including decorin (DCN), tumor necrosis factor receptor superfamily member 12A (TNFRSF12A) and chemokine (C-X-C motif) ligand 13 (CXCL13) were elevated in COVID-19 patients compared to healthy subjects. Moreover, we found incrementing expression of monocyte chemotactic protein-3 (MCP-3) and hepatocyte growth factor (HGF) when comparing moderate to severe COVID-19. Conclusions: Both extracellular matrix- and inflammation-associated proteins were identified as overlapping with pulmonary fibrosis, where we found DCN, TNFRSF12A, CXCL13, CXCL9, MCP-3 and HGF to be of particular interest to follow up on for the prediction of disease severity.

Endoplasmic reticulum stress in acute lung injury and pulmonary fibrosis

Pulmonary fibrosis (PF) is a progressive and irreversible lung disease that leads to diminished lung function, respiratory failure, and ultimately death and typically has a poor prognosis, with an average survival time of 2 to 5 years. Related articles suggested that endoplasmic reticulum (ER) stress played a critical role in the occurrence and progression of PF. The ER is responsible for maintaining protein homeostasis. However, factors such as aging, hypoxia, oxidative stress, or inflammation can disrupt this balance, promoting the accumulation of misfolded proteins in the ER and triggering ER stress. To cope with this situation, cells activate the unfolded protein response (UPR). Since acute lung injury (ALI) is one of the key onset events of PF, in this review, we will discuss the role of ER stress in ALI and PF by activating multiple signaling pathways and molecular mechanisms that affect the function and behavior of different cell types, with a focus on epithelial cells, fibroblasts, and macrophages. Linking ER stress to these cell types may broaden our understanding of the mechanisms underlying lung fibrosis and help us target these cells through these mechanisms. The relationship between ER stress and PF is still evolving, and future research will explore new strategies to regulate UPR pathways, providing novel therapeutic targets.

Pulmonary fibrosis treatment in children - What have we learnt from studies in adults?

Pulmonary fibrosis (PF) in children is a rare complication of specific forms of childhood interstitial lung diseases (chILD) with extremely limited scientific evidence to guide optimal management. Whilst there continues to be significant progress in PF management for adult populations, paediatric guidelines have stagnated. New anti-fibrotic medications (nintedanib and pirfenidone) are finding regular use amongst adult PF patients but remain largely unstudied and untested in children. Although there are major differences between the two age-group populations, it is useful to learn from the evolution of adult PF management, especially in the absence of dedicated paediatric studies. Whilst there have been recent trials aimed at assessing the safety and efficacy of drugs such as nintedanib and hydroxychloroquine, there is still a dire need for more research aimed at further assessing current treatment practices and evaluating the safety and efficacy of new emerging treatments in the paediatric population.

Molecular imaging in experimental pulmonary fibrosis reveals that nintedanib unexpectedly modulates CCR2 immune cell infiltration

BACKGROUND

Pulmonary fibrosis is a challenging clinical problem with lung pathology featuring immune cell infiltrates, fibroblast expansion, and matrix deposition. Molecular analysis of diseased lungs and preclinical models have uncovered C-C chemokine receptor type 2 (CCR2)+ monocyte egress from the bone marrow into the lung, where they acquire profibrotic activities. Current drug treatment is focused on fibroblast activity. Alternatively, therapeutic targeting and monitoring CCR2+ cells may be an effective patient management strategy.

METHODS

Inhibition of CCR2+ cells and, as a benchmark, the clinical antifibrotic agent, nintedanib, were used in mouse lung fibrosis models. Lungs were evaluated directly for CCR2+ cell infiltration and by non-invasive CCR2+ positron emission tomography imaging (CCR2-PET).

FINDINGS

Lung CCR2+ cells were significantly elevated in the bleomycin model as determined by tissue evaluation and CCR2-PET imaging. A protective treatment protocol with an oral CCR2 inhibitor was compared to oral nintedanib. While we expected disparate effects on CCR2+ cells, each drug similarly decreased lung CCR2+ cells and fibrosis. Chemotaxis assays showed nintedanib indirectly inhibited C-C motif chemokine 2 (CCL2)-mediated migration of CCR2+ cells. Even delayed therapeutic administration of nintedanib in bleomycin and the silicosis progressive fibrosis models decreased the accumulation of CCR2+ lung cells. In these treatments early CCR2-PET imaging predicted the later development of fibrosis.

INTERPRETATION

The inhibition of CCR2+ cell egress is likely a critical controller for stabilising lung fibrosis, as provided by nintedanib. Imaging with CCR2-PET may be useful to monitor nintedanib treatment responses, guide decision-making in the treatment of patients with progressive pulmonary fibrosis, and as a biomarker for drug development.

FUNDING

National Institutes of Health (NIH), R01HL131908 (SLB), R35HL145212 (YL), P41EB025815 (YL), K01DK133670 (DHK); Barnes Jewish Hospital Foundation (SLB).

Patient Profile-Based Management with Nintedanib in Patients with Idiopathic Pulmonary Fibrosis

A severe and progressive interstitial lung disease (ILD) known as idiopathic pulmonary fibrosis (IPF) has an unknown etiology with poorly defined mechanisms of development. Among the currently prescribed pharmacological interventions for IPF, nintedanib demonstrates the ability to decelerate the deterioration of lung function and yield positive clinical outcomes. Multiple randomized placebo-controlled trials have confirmed the efficacy and acceptable safety profile of nintedanib. Real-world evidence studies also support the use of nintedanib in IPF, being an efficient and well-tolerated treatment option. It has the potential to stabilize the disease progression in patients with ILD. Patients with IPF frequently have comorbidities like diabetes and hypertension, which can exacerbate the course of disease, reduce quality of life, and decrease treatment adherence. For well-informed decision-making, it is important for healthcare professionals to recognize the position of nintedanib therapy in IPF with comorbidities. The gastrointestinal adverse effects, notably diarrhea, dominate the nintedanib safety profile. These can be effectively controlled by closely monitoring side effects, administering anti-diarrheal and anti-emetic drugs, reducing the nintedanib dose, and discontinuing it in case of severe symptoms with an option to reintroduce the treatment after side effects subside. Symptomatic interventions and monitoring of liver enzymes may reduce the occurrence of permanent treatment discontinuations.