Heart Lung. 2024 Apr 2;67:1-4. doi: 10.1016/j.hrtlng.2024.03.007. Online ahead of print.

ABSTRACT

BACKGROUND: Few studies have investigated the prevalence of pathogens in patients with acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF), specifically, the interactions between respiratory pathogens and AE-IPF during the coronavirus disease 2019 (COVID-19) pandemic.

OBJECTIVES: We aimed to analyze pathogens in patients with AE-IPF between September 2020 and December 2022.

METHODS: This retrospective observational study was conducted at our hospital between September 2020 and December 2022. In patients with AE-IPF, pre-hospitalization polymerase chain reaction (PCR) tests for respiratory pathogens, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), were performed using multiplex PCR or Smart Gene assay with nasopharyngeal swab specimens. Microbiological assays, including Gram staining, sputum cultures, blood cultures, and urinary antigen tests for Streptococcus pneumoniae and Legionella pneumophila, were also performed.

RESULTS: Forty-nine patients with AE-IPF were included. The median age was 75 years old and 42 (86 %) were male. Only one of the 49 patients (2 %) was positive for SARS-CoV-2. Two of 28 patients (7 %) were positive for human rhinovirus/enterovirus. No bacteria were detected in sputum culture, blood culture, or urinary antigen tests.

CONCLUSIONS: The detection frequency of SARS-CoV-2 infection in patients with AE-IPF was lower than that of human rhinovirus/enterovirus. Continuous analysis for the presence of pathogens is necessary for appropriate infection control because respiratory viruses may increase as the coronavirus pandemic subsides.

PMID:38569435 | DOI:10.1016/j.hrtlng.2024.03.007

BMC Pulm Med. 2024 Apr 3;24(1):163. doi: 10.1186/s12890-024-02974-2.

ABSTRACT

BACKGROUND: Observational studies have shown that smoking is related to the diffusing capacity of the lungs for carbon monoxide (DLCO) in individuals with idiopathic pulmonary fibrosis (IPF). Nevertheless, further investigation is needed to determine the causal effect between these two variables. Therefore, we conducted a study to investigate the causal relationship between smoking and DLCO in IPF patients using two-sample Mendelian randomization (MR) analysis.

METHODS: Large-scale genome-wide association study (GWAS) datasets from individuals of European descent were analysed. These datasets included published lifetime smoking index (LSI) data for 462,690 participants and DLCO data for 975 IPF patients. The inverse-variance weighting (IVW) method was the main method used in our analysis. Sensitivity analyses were performed by MR‒Egger regression, Cochran's Q test, the leave-one-out test and the MR-PRESSO global test.

RESULTS: A genetically predicted increase in LSI was associated with a decrease in DLCO in IPF patients [ORIVW = 0.54; 95% CI 0.32-0.93; P = 0.02].

CONCLUSIONS: Our study suggested that smoking is associated with a decrease in DLCO. Patients diagnosed with IPF should adopt an active and healthy lifestyle, especially by quitting smoking, which may be effective at slowing the progression of IPF.

PMID:38570751 | DOI:10.1186/s12890-024-02974-2

BMJ Open Respir Res. 2023 Dec 12;10(1):e001850. doi: 10.1136/bmjresp-2023-001850.

ABSTRACT

BACKGROUND: Collagen XIII is a transmembrane collagen associated with neuromuscular junction development, and in humans its deficiency results in congenital myasthenic syndrome type 19 (CMS19), which leads to breathing difficulties. CMS19 patients usually have restricted lung capacity and one patient developed chronic lung disease. In single-cell RNA sequencing studies, collagen XIII has been identified as a marker for pulmonary lipofibroblasts, which have been implicated in the resolution of pulmonary fibrosis.

METHODS: We investigated the location and function of collagen XIII in the lung to understand the origin of pulmonary symptoms in human CMS19 patients. Additionally, we performed immunostainings on idiopathic pulmonary fibrosis (IPF) samples (N=5) and both normal and fibrotic mouse lung. To study whether the lack of collagen XIII predisposes to restrictive lung disease, we exposed Col13a1-modified mice to bleomycin-induced pulmonary fibrosis.

RESULTS: Apparently normal alveolar septum sections of IPF patients' lungs stained faintly for collagen XIII, and its expression was pinpointed to the septal fibroblasts in the mouse lung. Lung capacity was increased in mice lacking collagen XIII by over 10%. In IPF samples, collagen XIII was expressed by basal epithelial cells, hyperplastic alveolar epithelial cells and stromal cells in fibrotic areas, but the development of pulmonary fibrosis was unaffected in collagen XIII-deficient mice.

CONCLUSIONS: Changes in mouse lung function appear to represent a myasthenic manifestation of collagen XIII deficiency. We suggest that respiratory muscle myasthenia is the primary cause of the breathing problems suffered by CMS19 patients in addition to skeletal deformities. Induction of collagen XIII expression in the IPF patients' lungs warrants further studies to reveal collagen XIII-dependent disease mechanisms.

PMID:38568728 | DOI:10.1136/bmjresp-2023-001850

Sarcoidosis Vasc Diffuse Lung Dis. 2024 Mar 26;41(1):e2024002. doi: 10.36141/svdld.v41i1.15264.

ABSTRACT

BACKGROUND AND AIM: Idiopathic pulmonary fibrosis (IPF) is a fatal and progressive interstitial lung disease with varying degrees of hypoxemia. Long-term oxygen therapy (LTOT) is frequently used to treat hypoxemia, however the prognostic factors for better survival in IPF patients after initiation of LTOT remain unknown.

METHODS: We retrospectively investigated favorable factors of survival in consecutive 55 IPF patients with chronic respiratory failure who were introduced LTOT.

RESULTS: The 6-, 12-, 18-, and 24-month survival rates in IPF patients after introduction of LTOT were 70.9%, 49.0%, 45.2%, and 32.3%, respectively. Univariate analysis demonstrated that low Glasgow Prognostic Score (GPS) (hazard ratio [HR] 0.482, p=0.043) and treatment with antifibrotic agents (HR 0.401, p=0.013) were associated with favorable survival, while multivariate analysis revealed that treatment with antifibrotic agents was the independent predictor (HR 0.449, p=0.032). Moreover, IPF patients treated with antifibrotic agents with LTOT had significantly longer survival than those without antifibrotic agents (p = 0.0106).

CONCLUSION: In IPF patients who were introduced LTOT, treatment with antifibrotic agents was the independent factor for favorable survival. Treatment with antifibrotic agents may improve prognosis of IPF even after initiation of LTOT.

PMID:38567555 | DOI:10.36141/svdld.v41i1.15264

Front Immunol. 2024 Mar 19;15:1375171. doi: 10.3389/fimmu.2024.1375171. eCollection 2024.

ABSTRACT

BACKGROUND: The underlying molecular pathways of idiopathic pulmonary fibrosis (IPF), a progressive lung condition with a high death rate, are still mostly unknown. By using microarray datasets, this study aims to identify new genetic targets for IPF and provide light on the genetic factors that contribute to the development of IPF.

METHOD: We conducted a comprehensive analysis of three independent IPF datasets from the Gene Expression Omnibus (GEO) database, employing R software for data handling and normalization. Our evaluation of the relationships between differentially expressed genes (DEGs) and IPF included differential expression analysis, expression quantitative trait loci (eQTL) analysis, and Mendelian Randomization(MR) analyses. Additionally, we used Gene Set Enrichment Analysis (GSEA) and Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis to explore the functional roles and pathways of these genes. Finally, we validated the results obtained for the target genes.

RESULTS: We identified 486 highly expressed genes and 468 lowly expressed genes that play important roles in IPF. MR analysis identified six significantly co-expressed genes associated with IPF, specifically C12orf75, SPP1, ZG16B, LIN7A, PPP1R14A, and TLR2. These genes participate in essential biological processes and pathways, including macrophage activation and neural system regulation. Additionally, CIBERSORT analysis indicated a unique immune cell distribution in IPF, emphasized the significance of immunological processes in the disease. The MR analysis was consistent with the results of the analysis of variance in the validation cohort, which strengthens the reliability of our MR findings.

CONCLUSION: Our findings provide new insights into the molecular basis of IPF and highlight the promise of therapeutic interventions. They emphasize the potential of targeting specific molecular pathways for the treatment of IPF, laying the foundation for further research and clinical work.

PMID:38566986 | PMC:PMC10985171 | DOI:10.3389/fimmu.2024.1375171

Respirology. 2024 Apr 2. doi: 10.1111/resp.14719. Online ahead of print.

NO ABSTRACT

PMID:38565293 | DOI:10.1111/resp.14719

Respir Investig. 2024 Apr 1;62(3):465-480. doi: 10.1016/j.resinv.2024.03.006. Online ahead of print.

ABSTRACT

While idiopathic interstitial pneumonia (IIP) centering on idiopathic pulmonary fibrosis (IPF) is the most prevalent interstitial lung disease (ILD), especially in the older adult population, connective tissue disease (CTD)-related ILD is the second most prevalent ILD. The pathogenesis of IPF is primarily fibrosis, whereas that of other ILDs, particularly CTD-ILD, is mainly inflammation. Therefore, a precise diagnosis is crucial for selecting appropriate treatments, such as antifibrotic or immunosuppressive agents. In addition, some patients with IIP have CTD-related features, such as arthritis and skin eruption, but do not meet the criteria for any CTD, this is referred to as interstitial pneumonia with autoimmune features (IPAF). IPAF is closely associated with idiopathic nonspecific interstitial pneumonia (iNSIP) and cryptogenic organizing pneumonia (COP). Furthermore, patients with iNSIP or those with NSIP with OP overlap frequently develop polymyositis/dermatomyositis after the diagnosis of IIP. Acute exacerbation of ILD, the most common cause of death, occurs more frequently in patients with IPF than in those with other ILDs. Although acute exacerbation of CTD-ILD occurs at a low rate of incidence, patients with rheumatoid arthritis, microscopic polyangiitis, or systemic sclerosis experience more acute exacerbation of CTD-ILD than those with other CTD. In this review, the features of each IIP, focusing on CTD-related signatures, are summarized, and the pathogenesis and appropriate treatments to improve the prognoses of patients with various ILDs are discussed.

PMID:38564878 | DOI:10.1016/j.resinv.2024.03.006

Respir Res. 2024 Apr 2;25(1):153. doi: 10.1186/s12931-024-02786-2.

ABSTRACT

BACKGROUND: Wnt/β-catenin signaling is critical for lung development and AT2 stem cell maintenance in adults, but excessive pathway activation has been associated with pulmonary fibrosis, both in animal models and human diseases such as idiopathic pulmonary fibrosis (IPF). IPF is a detrimental interstitial lung disease, and although two approved drugs limit functional decline, transplantation is the only treatment that extends survival, highlighting the need for regenerative therapies.

METHODS: Using our antibody-based platform of Wnt/β-catenin modulators, we investigated the ability of a pathway antagonist and pathway activators to reduce pulmonary fibrosis in the acute bleomycin model, and we tested the ability of a WNT mimetic to affect alveolar organoid cultures.

RESULTS: A WNT mimetic agonist with broad FZD-binding specificity (FZD1,2,5,7,8) potently expanded alveolar organoids. Upon therapeutic dosing, a broad FZD-binding specific Wnt mimetic decreased pulmonary inflammation and fibrosis and increased lung function in the bleomycin model, and it impacted multiple lung cell types in vivo.

CONCLUSIONS: Our results highlight the unexpected capacity of a WNT mimetic to effect tissue repair after lung damage and support the continued development of Wnt/β-catenin pathway modulation for the treatment of pulmonary fibrosis.

PMID:38566174 | DOI:10.1186/s12931-024-02786-2

Respir Res. 2024 Apr 2;25(1):154. doi: 10.1186/s12931-024-02777-3.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fatal, and aging-associated interstitial lung disease with a poor prognosis and limited treatment options, while the pathogenesis remains elusive. In this study, we found that the expression of nuclear receptor subfamily 2 group F member 2 (NR2F2), a member of the steroid thyroid hormone superfamily of nuclear receptors, was reduced in both IPF and bleomycin-induced fibrotic lungs, markedly in bleomycin-induced senescent epithelial cells. Inhibition of NR2F2 expression increased the expression of senescence markers such as p21 and p16 in lung epithelial cells, and activated fibroblasts through epithelial-mesenchymal crosstalk, inversely overexpression of NR2F2 alleviated bleomycin-induced epithelial cell senescence and inhibited fibroblast activation. Subsequent mechanistic studies revealed that overexpression of NR2F2 alleviated DNA damage in lung epithelial cells and inhibited cell senescence. Adenovirus-mediated Nr2f2 overexpression attenuated bleomycin-induced lung fibrosis and cell senescence in mice. In summary, these data demonstrate that NR2F2 is involved in lung epithelial cell senescence, and targeting NR2F2 may be a promising therapeutic approach against lung cell senescence and fibrosis.

PMID:38566093 | DOI:10.1186/s12931-024-02777-3

BMC Pulm Med. 2024 Apr 2;24(1):160. doi: 10.1186/s12890-024-02947-5.

ABSTRACT

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has had a significant impact on global health and economies, resulting in millions of infections and deaths. This retrospective cohort study aimed to investigate the effect of antifibrotic agents (nintedanib and pirfenidone) on 1-year mortality in COVID-19 patients with acute respiratory failure.

METHODS: Data from 61 healthcare organizations in the TriNetX database were analyzed. Adult patients with COVID-19 and acute respiratory failure were included. Patients with a pre-existing diagnosis of idiopathic pulmonary fibrosis before their COVID-19 diagnosis were excluded. The study population was divided into an antifibrotic group and a control group. Propensity score matching was used to compare outcomes, and hazard ratios (HR) for 1-year mortality were calculated.

RESULTS: The antifibrotic group exhibited a significantly lower 1-year mortality rate compared to the control group. The survival probability at the end of the study was 84.42% in the antifibrotic group and 69.87% in the control group. The Log-Rank test yielded a p-value of less than 0.001. The hazard ratio was 0.434 (95% CI: 0.264-0.712), indicating a significant reduction in 1-year mortality in the antifibrotic group. Subgroup analysis demonstrated significantly improved 1-year survival in patients receiving nintedanib treatment and during periods when the Wuhan strain was predominant.

DISCUSSION: This study is the first to demonstrate a survival benefit of antifibrotic agents in COVID-19 patients with acute respiratory failure. Further research and clinical trials are needed to confirm the efficacy of these antifibrotic agents in the context of COVID-19 and acute respiratory failure.

PMID:38566026 | DOI:10.1186/s12890-024-02947-5

Sci Rep. 2024 Apr 2;14(1):7805. doi: 10.1038/s41598-024-58417-9.

ABSTRACT

Given the pleiotropic effects of statins beyond their lipid-lowering effects, there have been attempts to evaluate the role of statin therapy in IPF, but they have shown inconclusive results. Data from the National Health Insurance Service (NHIS) database of South Korea were used to investigate the effects of statin therapy on IPF. The IPF cohort consisted of a total of 10,568 patients who were newly diagnosed with IPF between 2010 and 2017. These patients were then matched in a 1:3 ratio to 31,704 subjects from a control cohort without IPF, with matching based on age and sex. A case-control study was performed to evaluate the association between statin use and the risk for IPF, and the multivariable analysis revealed that statin use was associated with a lower risk for IPF (adjusted OR 0.847, 95% CI 0.800-0.898). Using the IPF cohort, we also evaluated whether statin use at the time of diagnosis was associated with future clinical outcomes. The statin use at the time of IPF diagnosis was associated with improved overall survival (adjusted HR 0.779, 95% CI 0.709-0.856). Further prospective studies are needed to clarify the role of statin therapy in IPF.

PMID:38565856 | DOI:10.1038/s41598-024-58417-9

Int J Tuberc Lung Dis. 2024 Apr 1;28(4):183-188. doi: 10.5588/ijtld.23.0474.

ABSTRACT

<sec id="st1"><title>BACKGROUND</title>Due to paucity of literature data, we aimed at evaluating the prognostic role of the ratio of tricuspid annular plane systolic excursion (TAPSE) to systolic pulmonary artery pressure (SPAP) in idiopathic pulmonary fibrosis (IPF) patients without severe pulmonary hypertension and at assessing its correlation with effective arterial elastance index (EaI).</sec><sec id="st2"><title>METHODS</title>Multi-instrumental data obtained in 60 IPF patients (73.2 ± 6.8 years) and 60 matched controls were retrospectively analysed. Primary endpoint was all-cause mortality, while secondary endpoint was the composite of all-cause mortality and re-hospitalisations for all-causes over medium-term follow-up.</sec><sec id="st3"><title>RESULTS</title>At baseline, TAPSE/SPAP was significantly lower in patients with IPF than in controls (0.36 ± 0.25 vs. 0.77 ± 0.18 mm/mmHg; P < 0.001). TAPSE/SPAP was inversely correlated with EaI (r = -0.96) in IPF patients. During follow-up (3.5 ± 1.5 years), 21 patients died and 25 were re-hospitalised due to cardiopulmonary causes. TAPSE/SPAP was independently associated with both primary (HR 0.79, 95%CI 0.65-0.97) and secondary (HR 0.94, 95%CI 0.92-0.97) endpoints. A TAPSE/SPAP ratio of <0.20 and <0.44 mm/mmHg showed the greatest sensitivity and specificity for predicting primary (AUC 0.98) and secondary (AUC 0.99) endpoints, respectively.</sec><sec id="st4"><title>CONCLUSIONS</title>TAPSE/SPAP is a strong predictor of adverse outcomes in mild-to-moderate IPF. The strong correlation between TAPSE/SPAP and EaI might be an expression of a systemic fibrotic process which involves the heart, lungs and circulation.</sec>.

PMID:38563341 | DOI:10.5588/ijtld.23.0474

Eur J Pharmacol. 2024 Mar 30:176547. doi: 10.1016/j.ejphar.2024.176547. Online ahead of print.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) associated to pulmonary hypertension (PH) portends a poor prognosis, characterized by lung parenchyma fibrosis and pulmonary artery remodeling. Serum and parenchyma levels of Interleukin 11 (IL-11) are elevated in IPF-PH patients and contributes to pulmonary artery remodeling and PH. However, the effect of current approved therapies against IPF in pulmonary artery remodeling induced by IL-11 is unknown. The aim of this study is to analyze the effects of nintedanib and pirfenidone on pulmonary artery endothelial and smooth muscle cell remodeling induced by IL-11 in vitro. Our results show that nintedanib (NTD) and pirfenidone (PFD) ameliorates endothelial to mesenchymal transition (EnMT), pulmonary artery smooth muscle cell to myofibroblast-like transformation and pulmonary remodeling in precision lung cut slices. This study provided also evidence of the inhibitory effect of PFD and NTD on IL-11-induced endothelial and muscle cells proliferation and senescence. The inhibitory effect of these drugs on monocyte arrest and angiogenesis was also studied. Finally, we observed that IL-11 induced canonical signal transducer and activator of transcription 3 (STAT3) and non-canonical mitogen-activated protein kinase 1/2 (ERK1/2) phosphorylation, but, PFD and NTD only inhibited ERK1/2 phosphorylation. Therefore, this study provided evidence of the inhibitory effect of NTD and PFD on markers of pulmonary artery remodeling induced by IL-11.

PMID:38561103 | DOI:10.1016/j.ejphar.2024.176547

Biochem Pharmacol. 2024 Mar 30:116187. doi: 10.1016/j.bcp.2024.116187. Online ahead of print.

ABSTRACT

Metabolic reprogramming underlies the etiology and pathophysiology of respiratory diseases such as asthma, idiopathic pulmonary fibrosis (IPF), and chronic obstructive pulmonary disease (COPD). The dysregulated cellular activities driving airway inflammation and remodelling in these diseases have reportedly been linked to aberrant shifts in energy-producing metabolic pathways: glycolysis and oxidative phosphorylation (OXPHOS). The rewiring of glycolysis and OXPHOS accompanying the therapeutic effects of many clinical compounds and natural products in asthma, IPF, and COPD, supports targeting metabolism as a therapeutic approach for respiratory diseases. Correspondingly, inhibiting glycolysis has largely attested effective against experimental asthma, IPF, and COPD. However, modulating OXPHOS and its supporting catabolic pathways like mitochondrial pyruvate catabolism, fatty acid β-oxidation (FAO), and glutaminolysis for these respiratory diseases remain inconclusive. An emerging repertoire of metabolic enzymes are also interconnected to these canonical metabolic pathways that similarly possess therapeutic potential for respiratory diseases. Taken together, this review highlights the urgent demand for future studies to ascertain the role of OXPHOS in different respiratory diseases, under different stimulatory conditions, and in different cell types. While this review provides strong experimental evidence in support of the inhibition of glycolysis for asthma, IPF, and COPD, further verification by clinical trials is definitely required.

PMID:38561090 | DOI:10.1016/j.bcp.2024.116187

Cureus. 2024 Mar 1;16(3):e55344. doi: 10.7759/cureus.55344. eCollection 2024 Mar.

ABSTRACT

An uncommon illness known as fibrosing mediastinitis causes the mediastinum to grow excessively thick fibrous tissue. Fungal or idiopathic origins are the most common etiologies of pathology. In an individual suffering from chronic obstructive pulmonary disease (COPD), fibrosing mediastinitis, which resembled a bronchogenic cancer, was identified during anatomopathological examination following mediastinoscopy.

PMID:38559524 | PMC:PMC10981926 | DOI:10.7759/cureus.55344

Respir Med Case Rep. 2024 Mar 22;49:102016. doi: 10.1016/j.rmcr.2024.102016. eCollection 2024.

ABSTRACT

Oscillometry is an emerging pulmonary function testing tool that is conducted during tidal breaths with minimal patient effort. It is highly sensitive to changes in lung mechanics. Oscillometry was recently shown to be highly associated with disease severity in idiopathic pulmonary fibrosis (IPF). The usefulness of oscillometry after single lung transplant in IPF patients is not well understood. Our study demonstrated that oscillometry can detect changes in the graft despite presence of a native fibrotic lung to provide useful information to complement spirometry.

PMID:38559325 | PMC:PMC10973643 | DOI:10.1016/j.rmcr.2024.102016

bioRxiv [Preprint]. 2024 Mar 17:2024.03.15.584457. doi: 10.1101/2024.03.15.584457.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is characterized by progressive scarring and loss of lung function. With limited treatment options, patients succumb to the disease within 2-5 years. The molecular pathogenesis of IPF regarding the immunologic changes that occur is poorly understood. We characterize a role for non-canonical aryl-hydrocarbon receptor signaling (ncAHR) in dendritic cells (DCs) that leads to production of IL-6 and IL-17, promoting fibrosis. TLR9 signaling in myofibroblasts is shown to regulate production of TDO2 which converts tryptophan into the endogenous AHR ligand kynurenine. Mice with augmented ncAHR signaling were created by crossing floxed AHR exon-2 deletion mice (AHR Δex2 ) with mice harboring a CD11c-Cre. Bleomycin was used to study fibrotic pathogenesis. Isolated CD11c+ cells and primary fibroblasts were treated ex-vivo with relevant TLR agonists and AHR modulating compounds to study how AHR signaling influenced inflammatory cytokine production. Human datasets were also interrogated. Inhibition of all AHR signaling rescued fibrosis, however, AHR Δex2 mice treated with bleomycin developed more fibrosis and DCs from these mice were hyperinflammatory and profibrotic upon adoptive transfer. Treatment of fibrotic fibroblasts with TLR9 agonist increased expression of TDO2. Study of human samples corroborate the relevance of these findings in IPF patients. We also, for the first time, identify that AHR exon-2 floxed mice retain capacity for ncAHR signaling.

PMID:38559175 | PMC:PMC10980010 | DOI:10.1101/2024.03.15.584457

bioRxiv [Preprint]. 2024 Mar 22:2024.03.15.585249. doi: 10.1101/2024.03.15.585249.

ABSTRACT

Investigating the molecular, cellular, and tissue-level changes caused by disease, and the effects of pharmacological treatments across these biological scales, necessitates the use of multiscale computational modeling in combination with experimentation. Many diseases dynamically alter the tissue microenvironment in ways that trigger microvascular network remodeling, which leads to the expansion or regression of microvessel networks. When microvessels undergo remodeling in idiopathic pulmonary fibrosis (IPF), functional gas exchange is impaired due to loss of alveolar structures and lung function declines. Here, we integrated a multiscale computational model with independent experiments to investigate how combinations of biomechanical and biochemical cues in IPF alter cell fate decisions leading to microvascular remodeling. Our computational model predicted that extracellular matrix (ECM) stiffening reduced microvessel area, which was accompanied by physical uncoupling of endothelial cell (ECs) and pericytes, the cells that comprise microvessels. Nintedanib, an FDA-approved drug for treating IPF, was predicted to further potentiate microvessel regression by decreasing the percentage of quiescent pericytes while increasing the percentage of pericytes undergoing pericyte-myofibroblast transition (PMT) in high ECM stiffnesses. Importantly, the model suggested that YAP/TAZ inhibition may overcome the deleterious effects of nintedanib by promoting EC-pericyte coupling and maintaining microvessel homeostasis. Overall, our combination of computational and experimental modeling can explain how cell decisions affect tissue changes during disease and in response to treatments.

PMID:38559112 | PMC:PMC10979947 | DOI:10.1101/2024.03.15.585249

bioRxiv [Preprint]. 2024 Mar 14:2024.03.13.584814. doi: 10.1101/2024.03.13.584814.

ABSTRACT

Pulmonary fibrosis is a devastating disease with no effective treatments to cure, stop or reverse the unremitting, fatal fibrosis. A critical barrier to treating this disease is the lack of understanding of the pathways leading to fibrosis as well as those regulating the resolution of fibrosis. Fibrosis is the pathologic side of normal tissue repair that results when the normal wound healing programs go awry. Successful resolution of tissue injury requires several highly coordinated pathways, and this research focuses on the interplay between these overlapping pathways: immune effectors, inflammatory mediators and fibroproliferation in the resolution of fibrosis. Previously we have successfully prevented, mitigated, and even reversed established fibrosis using vaccinia vaccination immunotherapy in two models of murine lung fibrosis. The mechanism by which vaccinia reverses fibrosis is by vaccine induced lung specific Th1 skewed tissue resident memory (TRMs) in the lung. In this study, we isolated a population of vaccine induced TRMs - CD49a + CD4 + T cells - that are both necessary and sufficient to reverse established pulmonary fibrosis. Using adoptive cellular therapy, we demonstrate that intratracheal administration of CD49a + CD4 + TRMs into established fibrosis, reverses the fibrosis histologically, by promoting a decrease in collagen, and functionally, by improving lung function, without the need for vaccination. Furthermore, co-culture of in vitro derived CD49 + CD4 + human TRMs with human fibroblasts from individuals with idiopathic pulmonary fibrosis (IPF) results in the down regulation of IPF fibroblast collagen production. Lastly, we demonstrate in human IPF lung histologic samples that CD49a + CD4 + TRMs, which can down regulate human IPF fibroblast function, fail to increase in the IPF lungs, thus potentially failing to promote resolution. Thus, we define a novel unappreciated role for tissue resident memory T cells in regulating established lung fibrosis to promote resolution of fibrosis and re-establish lung homeostasis. We demonstrate that immunotherapy, in the form of adoptive transfer of CD49a + CD4 + TRMs into the lungs of mice with established fibrosis, not only stops progression of the fibrosis but more importantly reverses the fibrosis. These studies provide the insight and preclinical rationale for a novel paradigm shifting approach of using cellular immunotherapy to treat lung fibrosis.

PMID:38559095 | PMC:PMC10980005 | DOI:10.1101/2024.03.13.584814

Yakugaku Zasshi. 2024;144(4):397-402. doi: 10.1248/yakushi.23-00165-2.

ABSTRACT

Cysts are abnormal fluid-filled sacs found in various human organs, including the liver. Liver cysts can be associated with known causes such as parasite infections and gene mutations, or simply aging. Among these causes, simple liver cysts are often found in elderly people. While they are generally benign, they may occasionally grow but rarely shrink with age, indicating their clear association with aging. However, the mechanism behind the formation of simple liver cysts has not been thoroughly investigated. Recently, we have generated transgenic mice that specifically overexpress fibroblast growth factor (FGF)18 in hepatocytes. These mice exhibit severe liver fibrosis without inflammation and spontaneously develop liver cysts that grow with age. Our findings suggest that simple liver cysts can be induced by fibrosis accompanied by sterile inflammation or injury, whereas fibrosis accompanied by severe inflammation or injury may lead to cirrhosis. We also discuss the detrimental effects of disease- and aging-associated fibrosis in various organs, such as the heart, lungs, and kidneys. Additionally, we provide a brief summary of the two currently approved anti-fibrotic drugs for idiopathic pulmonary fibrosis, nintedanib and pirfenidone, as well as their possibility of future expansion of application toward other fibrotic diseases.

PMID:38556314 | DOI:10.1248/yakushi.23-00165-2