Respir Res. 2022 Aug 13;23(1):206. doi: 10.1186/s12931-022-02129-z.

ABSTRACT

BACKGROUND: Variants of NHL repeat-containing protein 2 (NHLRC2) have been associated with severe fibrotic interstitial lung disease in early childhood and NHLRC2 has been listed as a differentially expressed gene between rapidly and slowly progressing idiopathic pulmonary fibrosis (IPF) patients. However, its cell type-specific localization in human lung tissue is unknown. The aim of this study was to evaluate NHLRC2 mRNA and protein expression in different cell types of lung tissue samples and to investigate the effect of transforming growth factor (TGF)-β1 exposure on NHLRC2 expression in vitro.

METHODS: The NHLRC2 expression in lung tissue samples was studied by immunohistochemistry (50 IPF, 10 controls) and mRNA in situ hybridization (8 IPF, 3 controls). The immunohistochemical NHLRC2 expression was quantified with image analysis software and associated with the clinical and smoking data of the patients. NHLRC2 expression levels in primary stromal and small airway epithelial cell lines after exposure to TGF-β1 was measured by quantitative reverse transcription polymerase chain reaction and Western blot analysis.

RESULTS: NHLRC2 expression was detected especially in bronchiolar epithelial cells, type II pneumocytes and macrophages in normal lung. In the lungs of IPF patients, NHLRC2 was mainly expressed in hyperplastic alveolar epithelial cells lining fibroblast foci and honeycombs. NHLRC2 expression assessed by image analysis was higher in IPF compared to controls (p < 0.001). Ever-smokers had more prominent NHLRC2 staining than non-smokers (p = 0.037) among IPF patients. TGF-β1 exposure did not influence NHLRC2 levels in lung cell lines.

CONCLUSIONS: NHLRC2 expression was higher in IPF compared to controls being widely expressed in type II pneumocytes, macrophages, bronchiolar epithelium, and hyperplastic alveolar epithelium. Additionally, its expression was not regulated by the exposure to TGF-β1 in vitro. Further studies are needed to clarify the role of NHLRC2 in IPF.

PMID:35964085 | DOI:10.1186/s12931-022-02129-z

Pulmonology. 2022 Aug 10:S2531-0437(22)00137-4. doi: 10.1016/j.pulmoe.2022.06.008. Online ahead of print.

NO ABSTRACT

PMID:35963830 | DOI:10.1016/j.pulmoe.2022.06.008

Eur J Med Chem. 2022 Aug 6;241:114643. doi: 10.1016/j.ejmech.2022.114643. Online ahead of print.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a highly fatal disease that lacks appropriate treatments and highly effective drugs. Many reported indicated that the TGF-β1/Smad3 signaling pathway played a pivotal role in development of IPF. In this case, it was hypothesized that discovery novel compounds to block the TGF-β1/Smad3 signaling pathway might be useful for treatment of IPF. Therefore, a high-throughput screening system based on stably transfected CAGA-NIH3T3 cells was established for discovering lead compounds which could validly suppress the TGF-β1/Smad3 signal path. In this study, a series of novel Pleuromutilin derivatives were prepared and quickly evaluated by high-throughput assay. The lead compound 32 was discovered to be able to remarkably suppress the TGF-β1/Smad3 pathway in vitro. Further biological evaluation revealed that compound 32 could remarkably decrease the myofibroblast stimulation and extracellular matrix (ECM) deposition. More importantly, compound 32 could remarkably mitigate bleomycin (BLM)-triggered lung fibrosis in mice models. Additionally, the lead compound possess excellent pharmacokinetics properties, good oral availability and low toxicity. In general, our study has demonstrated the potency of a novel Pleuromutilin derivative (compound 32), which might be a prospective candidate for developing anti-IPF medicines by suppress the TGF-β1/Smad3 signal pathway.

PMID:35961069 | DOI:10.1016/j.ejmech.2022.114643

Medicine (Baltimore). 2022 Aug 12;101(32):e29936. doi: 10.1097/MD.0000000000029936.

ABSTRACT

Several previous reports have shown interstitial lung disease (ILD) to be a predictor of poor prognosis in patients with chronic pulmonary aspergillosis (CPA). However, there is a lack of clarity regarding patient background and the prognostic factors in CPA associated with ILD (CPA-ILD). Therefore, we assessed these points to obtain valuable information for clinical practice. We retrospectively surveyed and collected data from 459 patients who had serum examination for anti-Aspergillus antibody. Of these patients, we extracted and investigated CPA-ILD patients. We ultimately analyzed 32 CPA-ILD patients. Patient background factors more frequently showed the patients to be older (mean: 74.9 years), male (75.0%), and to have a smoking history (71.9%). Median survival time from the diagnosis of ILD was 76.0 months, whereas that from the diagnosis of CPA-ILD was 25.5 months. No significant differences in survival were found in regard to each ILD pattern and the presence of idiopathic pulmonary fibrosis. A higher level of C-reactive protein was a significant predictor of mortality by Cox regression analysis. CPA complicating ILD is associated with poor prognosis. ILD patients with older age, male sex, and smoking history should be aware of the potential for the development of CPA in ILD. If such patients have elevated markers of inflammation, prompt induction of antifungal treatment may improve their prognosis. Clinicians should be aware of which complications of CPA may lead to a poor prognosis for any ILD not just those limited to idiopathic pulmonary fibrosis or usual interstitial pneumonia pattern.

PMID:35960067 | DOI:10.1097/MD.0000000000029936

Cells. 2022 Aug 3;11(15):2396. doi: 10.3390/cells11152396.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a devastating interstitial lung disease with dire consequences and in urgent need of improved therapies. Compelling evidence indicates that damage or dysfunction of AT2s is of central importance in the development of IPF. We recently identified a novel AT2 subpopulation characterized by low SFTPC expression but that is enriched for PD-L1 in mice. These cells represent quiescent, immature AT2 cells during normal homeostasis and expand upon pneumonectomy (PNX) and were consequently named injury-activated alveolar progenitors (IAAPs). FGF10 is shown to play critical roles in lung development, homeostasis, and injury repair demonstrated in genetically engineered mice. In an effort to bridge the gap between the promising properties of endogenous Fgf10 manipulation and therapeutic reality, we here investigated whether the administration of exogenous recombinant FGF10 protein (rFGF10) can provide preventive and/or therapeutic benefit in a mouse model of bleomycin-induced pulmonary fibrosis with a focus on its impact on IAAP dynamics. C57BL/6 mice and SftpcCreERT2/+; tdTomatoflox/+ mice aged 8-10 weeks old were used in this study. To induce the bleomycin (BLM) model, mice were intratracheally (i.t.) instilled with BLM (2 μg/g body weight). BLM injury was induced after a 7-day washout period following tamoxifen induction. A single i.t. injection of rFGF10 (0.05 μg/g body weight) was given on days 0, 7, 14, and 21 after BLM injury. Then, the effects of rFGF10 on BLM-induced fibrosis in lung tissues were assessed by H&E, IHC, Masson's trichrome staining, hydroxyproline and Western blot assays. Immunofluorescence staining and flow cytometry was used to assess the dynamic behavior of AT2 lineage-labeled SftpcPos (IAAPs and mature AT2) during the course of pulmonary fibrosis. We observed that, depending on the timing of administration, rFGF10 exhibited robust preventive or therapeutic efficacy toward BLM-induced fibrosis based on the evaluation of various pathological parameters. Flow cytometric analysis revealed a dynamic expansion of IAAPs for up to 4 weeks following BLM injury while the number of mature AT2s was drastically reduced. Significantly, rFGF10 administration increased both the peak ratio and the duration of IAAPs expansion relative to EpCAMPos cells. Altogether, our results suggest that the administration of rFGF10 exhibits therapeutic potential for IPF most likely by promoting IAAP proliferation and alveolar repair.

PMID:35954241 | DOI:10.3390/cells11152396

Cells. 2022 Jul 28;11(15):2322. doi: 10.3390/cells11152322.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) affects an increasing number of people globally, yet treatment options remain limited. At present, conventional treatments depending on drug therapy do not show an ideal effect in reversing the lung damage or extending the lives of IPF patients. In recent years, more and more attention has focused on extracellular vesicles (EVs) which show extraordinary therapeutic effects in inflammation, fibrosis disease, and tissue damage repair in many kinds of disease therapy. More importantly, EVs can be modified or used as a drug or cytokine delivery tool, targeting injury sites to enhance treatment efficiency. In light of this, the treatment strategy of mesenchymal stem cell-extracellular vesicles (MSC-EVs) targeting the pulmonary microenvironment for IPF provides a new idea for the treatment of IPF. In this review, we summarized the inflammation, immune dysregulation, and extracellular matrix microenvironment (ECM) disorders in the IPF microenvironment in order to reveal the treatment strategy of MSC-EVs targeting the pulmonary microenvironment for IPF.

PMID:35954166 | DOI:10.3390/cells11152322

Am J Respir Crit Care Med. 2022 Aug 11. doi: 10.1164/rccm.202207-1301LE. Online ahead of print.

NO ABSTRACT

PMID:35950929 | DOI:10.1164/rccm.202207-1301LE

Am J Pathol. 2022 Aug 7:S0002-9440(22)00213-9. doi: 10.1016/j.ajpath.2022.07.005. Online ahead of print.

ABSTRACT

Idiopathic subglottic stenosis (iSGS) is a localized airway disease that almost exclusively affects females. Understanding the molecular mechanisms involved may provide insights leading to therapeutic interventions. Next-generation sequencing was performed on tissue sections from patients with iSGS (n=22), antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV, n=5), and matched controls (n=9) to explore candidate genes and mechanisms of disease. Gene expression changes were validated, and selected markers were identified by immunofluorescence staining. Epithelial-mesenchymal transition (EMT) and leukocyte extravasation pathways were the biological mechanisms most relevant to iSGS pathogenesis. Alternatively activated macrophages (M2) were abundant in the subepithelium and perisubmucosal glands of the airway in iSGS and AAV. Increased expression of the mesenchymal marker S100A4 and decreased expression of the epithelial marker EPCAM further supported a role for EMT, but to different extents in iSGS and ANCA-SGS. High expression of PMEPA1, an EMT regulator, in iSGS patients was associated with a shorter recurrence interval (25 vs. 116 months: HR=4.16, P=0.041, 95% CI: 1.056-15.60). Thus, EMT is a key pathogenetic mechanism of subglottic stenosis in iSGS and AAV. M2 macrophages contribute to the pathogenesis of both diseases, suggesting a shared pro-fibrotic mechanism, and PMEPA1 may be a biomarker for predicting disease recurrence in iSGS.

PMID:35948078 | DOI:10.1016/j.ajpath.2022.07.005

Int J Surg Pathol. 2022 Aug 9:10668969221117984. doi: 10.1177/10668969221117984. Online ahead of print.

ABSTRACT

Idiopathic pulmonary fibrosis is often associated with lung cancer, but early malignant lesions mixed with fibrous lesions are not always easy to diagnose. A 78-year-old woman was referred to our hospital due to a ground-glass nodule in the left upper lobe detected on chest high resolution computed tomography during follow-up of chronic idiopathic interstitial pneumonia. Pathological examination of the resected specimen revealed that the ground-glass nodule was locally progressed usual interstitial pneumonia (UIP). It should be noted that focal progression of UIP may occur and present with ground-glass nodule mimicking lung cancer, even if lesions in other areas remain unchanged. Moreover, in such cases, recognition of nodular lesions by the gross findings on the pleural surface and palpation during surgical resection are difficult and require precise marking.

PMID:35946121 | DOI:10.1177/10668969221117984

Am J Respir Crit Care Med. 2022 Aug 9. doi: 10.1164/rccm.202201-0124OC. Online ahead of print.

ABSTRACT

RATIONALE: Criteria for progressive pulmonary fibrosis (PPF) have been proposed, but their prognostic value beyond categorical decline in forced vital capacity (FVC) remains unclear.

OBJECTIVE: To determine whether proposed PPF criteria predict transplant-free survival (TFS) in patients with non-idiopathic pulmonary fibrosis (IPF) forms of interstitial lung disease (ILD).

METHODS: A retrospective, multi-center cohort analysis was performed. Patients diagnosed with fibrotic connective tissue disease associated ILD, fibrotic hypersensitivity pneumonitis and non-IPF idiopathic interstitial pneumonia from three US centers and one UK center comprised test and validation cohorts, respectively. Cox proportional hazards regression was used to test the association between five-year TFS and 10% FVC decline, followed by thirteen additional PPF criteria satisfied in the absence of >=10% FVC decline.

MAIN RESULTS: One thousand three hundred forty-one patients met inclusion criteria. A >=10% relative FVC decline was the strongest predictor of reduced TFS and showed consistent TFS association across cohorts, ILD subtypes and treatment groups, resulting in a phenotype that closely resembled IPF. Ten additional PPF criteria satisfied in the absence of >=10% relative FVC decline were also associated with reduced TFS in the US test cohort, with six maintaining TFS association in the UK validation cohort. Validated PPF criteria requiring a combination of physiologic, radiologic, and symptomatic worsening performed similarly to their stand-alone components but captured a smaller number of patients.

CONCLUSIONS: An FVC decline of >=10% and six additional PPF criteria satisfied in the absence of such decline identify non-IPF ILD patients at increased risk of death or lung transplant.

PMID:35943866 | DOI:10.1164/rccm.202201-0124OC

Am J Respir Crit Care Med. 2022 Aug 9. doi: 10.1164/rccm.202205-0910LE. Online ahead of print.

NO ABSTRACT

PMID:35943331 | DOI:10.1164/rccm.202205-0910LE

Am J Ind Med. 2022 Aug 8. doi: 10.1002/ajim.23419. Online ahead of print.

ABSTRACT

BACKGROUND: To evaluate trends of nonmalignant respiratory disease (NMRD) mortality among US underground uranium miners on the Colorado Plateau, and to estimate the exposure-response association between cumulative radon progeny exposure and NMRD subtype mortality.

METHODS: Standardized mortality ratios (SMRs) and excess relative rates per 100 working level months (excess relative rate [ERR]/100 WLM) were estimated in a cohort of 4021 male underground uranium miners who were followed from 1960 through 2016.

RESULTS: We observed elevated SMRs for all NMRD subtypes. Silicosis had the largest SMR (n = 52, SMR = 41.4; 95% confidence interval [CI]: 30.9, 54.3), followed by other pneumoconiosis (n = 49, SMR = 39.6; 95% CI: 29.6, 52.3) and idiopathic pulmonary fibrosis (IPF) (n = 64, SMR = 4.77; 95% CI 3.67, 6.09). SMRs for silicosis increased with duration of employment; SMRs for IPF increased with duration of employment and calendar period. There was a positive association between cumulative radon exposure and silicosis with evidence of modification by smoking (ERR/100 WLM≥10 pack-years = 0.78; 95% CI: 0.05, 24.6 and ERR/100 WLM<10 pack-years = 0.01; 95% CI: -0.03, 0.52), as well as a small positive association between radon and IPF (ERR/100 WLM = 0.06, 95% CI: 0.00, 0.24); these associations were driven by workers with prior employment in hard rock mining.

CONCLUSIONS: Uranium mining workers had excess NMRD mortality compared with the general population; this excess persisted throughout follow-up. Exposure-response analyses indicated a positive association between radon exposure and IPF and silicosis, but these analyses have limitations due to outcome misclassification and missing information on occupational co-exposures such as silica dust.

PMID:35941829 | DOI:10.1002/ajim.23419

Semin Oncol. 2022 Jul 21:S0093-7754(22)00057-4. doi: 10.1053/j.seminoncol.2022.07.003. Online ahead of print.

ABSTRACT

Shared decision making (SDM) is an important part of lung cancer screening (LCS) that includes discussing the risks and benefits of screening, potential outcomes, patient eligibility and willingness to participate, tobacco cessation, and tailoring a strategy to an individual patient. More than other cancer screening tests, eligibility for LCS is nuanced, incorporating the patient's age as well as tobacco use history and overall health status. Since comorbidities and multimorbidity (ie, 2 or more comorbidities) impact the risks and benefits of LCS, these topics are a fundamental part of decision-making. However, there is currently little evidence available to guide clinicians in addressing comorbidities and an individual's "appropriateness" for LCS during SDM visits. Therefore, this literature review investigates the impact of comorbidities and multimorbidity among patients undergoing LCS. Based on available evidence and guideline recommendations, we identify comorbidities that should be considered during SDM conversations and review best practices for navigating SDM conversations in the context of LCS. Three conditions are highlighted since they concomitantly portend higher risk of developing lung cancer, potentially increase risk of screening-related evaluation and treatment complications and can be associated with limited life expectancy: chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, and human immunodeficiency virus infection.

PMID:35940959 | DOI:10.1053/j.seminoncol.2022.07.003

Thorax. 2022 Aug 8:thoraxjnl-2022-219068. doi: 10.1136/thorax-2022-219068. Online ahead of print.

ABSTRACT

Interstitial lung abnormalities (ILA) can be incidentally detected in patients undergoing low-dose CT screening for lung cancer. In this retrospective study, we explore the downstream impact of ILA detection on interstitial lung disease (ILD) diagnosis and treatment. Using a targeted approach in a lung cancer screening programme, the rate of de novo ILD diagnosis was 1.5%. The extent of abnormality on CT and severity of lung function impairment, but not symptoms were the most important factors in differentiating ILA from ILD. Disease modifying therapies were commenced in 39% of ILD cases, the majority being antifibrotic therapy for idiopathic pulmonary fibrosis.

PMID:35940878 | DOI:10.1136/thorax-2022-219068

Ther Adv Respir Dis. 2022 Jan-Dec;16:17534666221117002. doi: 10.1177/17534666221117002.

ABSTRACT

Interstitial lung diseases (ILDs) other than idiopathic pulmonary fibrosis (IPF) have an array of immunomodulatory treatment options compared with IPF, due to their inflammatory component. However, there is a relative paucity of guidance on the management of this heterogeneous group of diseases. In ILDs other than IPF, immunosuppression is the cornerstone of therapy, with varying levels of evidence for different immunomodulatory agents and for each specific ILD. Classification of ILDs is important for guiding treatment decisions. Immunomodulatory agents mainly include corticosteroids, mycophenolate mofetil (MMF), azathioprine, methotrexate, cyclophosphamide and rituximab. In this review, the available evidence for single agents in the most common ILDs is first discussed. We then reviewed practical therapeutic approaches in connective tissue disease-related ILD and interstitial pneumonia with autoimmune features, scleroderma-related ILD, vasculitis and dermatomyositis with hypoxemic respiratory failure, idiopathic non-specific interstitial pneumonia, hypersensitivity pneumonitis sarcoidosis, fibrosing organizing pneumonia and eosinophilic pneumonia. The treatment of acute exacerbations of ILD is also discussed. Therapy augmentation in ILD is dictated by the recognition of progression of disease. Criteria for the evaluation of progression of disease are then discussed. Finally, specific protocol and measures to increase patients' safety are reviewed as well, including general monitoring and serologic surveillance, Pneumocystis jirovecii prophylaxis, patients' education, genetic testing for azathioprine, MMF serum levels and cyclophosphamide administration protocols. Immunomodulatory therapies are largely successful in the management of ILDs and can be safely managed with the application of specific protocols, precautions and monitoring.

PMID:35938712 | DOI:10.1177/17534666221117002

Curr Opin Pulm Med. 2022 Sep 1;28(5):407-413. doi: 10.1097/MCP.0000000000000908.

ABSTRACT

PURPOSE OF REVIEW: Idiopathic pulmonary fibrosis (IPF), characterized by relentless disease progression from the time of diagnosis, is part of a larger group of chronic fibrosing interstitial lung diseases (ILDs). A proportion of patients with non-IPF ILDs may develop, despite conventional treatment, a progressive pulmonary fibrosis (PPF), also referred to as ILD with a progressive fibrosing phenotype (PF-ILD). These patients experience worsening of respiratory symptoms, decline in lung function, and early mortality. The goal of this review is to describe the epidemiology and recent real-life cohorts of PF-ILD, with implications for management.

RECENT FINDINGS: The relatively new concept of PF-ILD has aroused active clinical research over the past years. To understand risk factors for progression and the real burden of the disease is crucial to improve management. In the last 2 years, different cohort studies have addressed these questions. They showed that almost one-third of the non-IPF fibrotic ILD patients develop PF-ILD or PPF.

SUMMARY: Emerging data show similarities in prognosis between patients with IPF or with non-IPF PF-ILD patients. Early detection and appropriate treatment of this group of patients is a priority. Further research is needed to identify risk factors of progression, to clarify the assessment of progression in clinical practice, for a better management of patients with PF-ILD in a real-world setting.

PMID:35938201 | DOI:10.1097/MCP.0000000000000908

Curr Opin Pulm Med. 2022 Sep 1;28(5):399-406. doi: 10.1097/MCP.0000000000000900.

ABSTRACT

PURPOSE OF REVIEW: The aim of this review was to summarize the recent data concerning interstitial lung disease after COVID-19, a field where knowledge is evolving very quickly.

RECENT FINDINGS: It has been found that a proportion of patients displayed fibrotic-like pattern on chest computed tomography shortly after COVID-19 pneumonia. Those lesions can potentially represent precursors of fibrosis, although most of them will resolve until 1 year postinfection. There was a wide range of the prevalence of post-COVID-19 interstitial lung disease detected in the literature, which can be attributed to the heterogeneous definition of lung abnormalities and the discrepancy of study design. The severity of acute COVID-19 disease has been linked to increased risk of residual imaging and functional abnormalities, while reduced DLco was the most common functional abnormality in long-term survivors. Studies indicated that pathophysiology of post-COVID interstitial lung disease shares common mechanisms with idiopathic pulmonary fibrosis. Regarding therapeutic strategies of post-COVID-19 interstitial lung disease, the role of immunosuppressive and antifibrotic treatment is currently under investigation.

SUMMARY: We still need to learn about the natural history of COVID-19 disease, allowing for a better targeting of therapeutic interventions through a multidisciplinary approach.

PMID:35938200 | DOI:10.1097/MCP.0000000000000900

Front Pharmacol. 2022 Jul 21;13:963054. doi: 10.3389/fphar.2022.963054. eCollection 2022.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease. Recent studies have identified the key role of crosstalk between dysregulated epithelial cells, mesenchymal, immune, and endothelial cells in IPF. In addition, genetic mutations and environmental factors (e.g., smoking) have also been associated with the development of IPF. With the recent development of sequencing technology, epigenetics, as an intermediate link between gene expression and environmental impacts, has also been reported to be implicated in pulmonary fibrosis. Although the etiology of IPF is unknown, many novel therapeutic targets and agents have emerged from clinical trials for IPF treatment in the past years, and the successful launch of pirfenidone and nintedanib has demonstrated the promising future of anti-IPF therapy. Therefore, we aimed to gain an in-depth understanding of the underlying molecular mechanisms and pathogenic factors of IPF, which would be helpful for the diagnosis of IPF, the development of anti-fibrotic drugs, and improving the prognosis of patients with IPF. In this study, we summarized the pathogenic mechanism, therapeutic targets and clinical trials from the perspective of multiple cell types, gene mutations, epigenetic and environmental factors.

PMID:35935869 | PMC:PMC9349351 | DOI:10.3389/fphar.2022.963054

Aging Cell. 2022 Aug 7. doi: 10.1111/acel.13674. Online ahead of print.

ABSTRACT

Mitochondrial dysfunction has been associated with age-related diseases, including idiopathic pulmonary fibrosis (IPF). We provide evidence that implicates chronic elevation of the mitochondrial anion carrier protein, uncoupling protein-2 (UCP2), in increased generation of reactive oxygen species, altered redox state and cellular bioenergetics, impaired fatty acid oxidation, and induction of myofibroblast senescence. This pro-oxidant senescence reprogramming occurs in concert with conventional actions of UCP2 as an uncoupler of oxidative phosphorylation with dissipation of the mitochondrial membrane potential. UCP2 is highly expressed in human IPF lung myofibroblasts and in aged fibroblasts. In an aging murine model of lung fibrosis, the in vivo silencing of UCP2 induces fibrosis regression. These studies indicate a pro-fibrotic function of UCP2 in chronic lung disease and support its therapeutic targeting in age-related diseases associated with impaired tissue regeneration and organ fibrosis.

PMID:35934931 | DOI:10.1111/acel.13674

Animal Model Exp Med. 2022 Aug 7. doi: 10.1002/ame2.12263. Online ahead of print.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF), characterized by aggravated alveolar destruction and fibrotic matrix deposition, tendentiously experiences the stage called acute exacerbation IPF (AE-IPF) and progresses to multiple organ damage, especially liver injury. Recent studies have found a variety of immune microenvironment disorders associated with elevated IPF risk and secondary organ injury, whereas current animal models induced with bleomycin (BLM) could not completely reflect the pathological manifestations of AE-IPF patients in clinic, and the exact underlying mechanisms are not yet fully explored. In the current study, we established an AE-IPF model by tracheal administration of a single dose of BLM and then repeated administrations of lipopolysaccharide in mice. This mouse model successfully recapitulated the clinical features of AE-IPF, including excessive intrapulmonary inflammation and fibrosis and extrapulmonary manifestations, as indicated by significant upregulation of Il6, Tnfa, Il1b, Tgfb, fibronectin, and Col1a1 in both lungs and liver and elevated serum aspartate transaminase and alanine transaminase levels. These effects might be attributed to the regulation of Th17 cells. By sharing this novel murine model, we expect to provide an appropriate experimental platform to investigate the pathogenesis of AE-IPF coupled with liver injury and contribute to the discovery and development of targeted interventions.

PMID:35934841 | DOI:10.1002/ame2.12263