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Background: Water electrospray technology has been developed and extensively studied for its physical properties and potential application as a non-chemical biocide against airborne pathogens. However, there are still concerns regarding the safety and potential toxicity of inhaling water electrospray (WE) particles. To address these potential hazards and offer insights into the impact of WE on humans, we analyzed the immunopathological response to WE by employing an intranasal challenge C57BL/6 mouse model. This analysis aimed to compare the effects of WE with those of sodium hypochlorite (SH), a well-known biocidal agent. Results: The study findings suggest that the WE did not trigger any pathological immune reactions in the intranasal-challenged C57BL/6 mouse model. Mice challenged with WE did not experience body weight loss, and there was no increase in inflammatory cytokine production compared to SH-treated mice. Histopathological analysis revealed that WE did not cause any damage to the lung tissue. In contrast, mice treated with SH exhibited significant lung tissue damage, characterized by the infiltration of neutrophils and eosinophils. Transcriptomic analysis of lung tissue further confirmed the absence of a pathological immune response in mice treated with WE compared to those treated with SH. Upon intranasal challenge with WE, the C57BL/6 mouse model did not show any evidence of immunopathological damage. Conclusions: The results of this study suggest that WE is a safe technology for disinfecting airborne pathogens. It demonstrated little to no effect on immune system activation and pathological outcomes in the intranasal challenge C57BL/6 mouse model. These findings not only support the potential use of WE as an effective and safe method for air disinfection but also highlight the value of the intranasal challenge of the C57BL/6 mouse model in providing significant immunopathological insights for assessing the inhalation of novel materials for potential use. [ABSTRACT FROM AUTHOR]

There is a reciprocal relationship between extracellular matrix (ECM) remodelling and inflammation that could be operating in the progression of severe COVID-19. To explore the immune-driven ECM remodelling in COVID-19, we in this explorative study analysed these interactions in hospitalised COVID-19 patients. RNA sequencing and flow analysis were performed on peripheral blood mononuclear cells. Inflammatory mediators in plasma were measured by ELISA and MSD, and clinical information from hospitalised COVID-19 patients (N=15) at admission was included in the analysis. Further, we reanalysed two publicly available datasets: (1) lung tissue RNA-sequencing dataset (N=5) and (2) proteomics dataset from PBCM. ECM remodelling pathways were enriched in PBMC from COVID-19 patients compared to healthy controls. Patients treated at the intensive care unit (ICU) expressed distinct ECM remodelling gene profiles compared to patients in the hospital ward. Several markers were strongly correlated to immune cell subsets, and the dysregulation in the ICU patients was positively associated with plasma levels of inflammatory cytokines and negatively associated with B-cell activating factors. Finally, our analysis of publicly accessible datasets revealed (i) an augmented ECM remodelling signature in inflamed lung tissue compared to non-inflamed tissue and (ii) proteomics analysis of PBMC from severe COVID-19 patients demonstrated an up-regulation in an ECM remodelling pathway. Our results may suggest the presence of an interaction between ECM remodelling, inflammation, and immune cells, potentially initiating or perpetuating pulmonary pathology in severe COVID-19. [ABSTRACT FROM AUTHOR]

Abstract Background Water electrospray technology has been developed and extensively studied for its physical properties and potential application as a non-chemical biocide against airborne pathogens. However, there are still concerns regarding the safety and potential toxicity of inhaling water electrospray (WE) particles. To address these potential hazards and offer insights into the impact of WE on humans, we analyzed the immunopathological response to WE by employing an intranasal challenge C57BL/6 mouse model. This analysis aimed to compare the effects of WE with those of sodium hypochlorite (SH), a well-known biocidal agent. Results The study findings suggest that the WE did not trigger any pathological immune reactions in the intranasal-challenged C57BL/6 mouse model. Mice challenged with WE did not experience body weight loss, and there was no increase in inflammatory cytokine production compared to SH-treated mice. Histopathological analysis revealed that WE did not cause any damage to the lung tissue. In contrast, mice treated with SH exhibited significant lung tissue damage, characterized by the infiltration of neutrophils and eosinophils. Transcriptomic analysis of lung tissue further confirmed the absence of a pathological immune response in mice treated with WE compared to those treated with SH. Upon intranasal challenge with WE, the C57BL/6 mouse model did not show any evidence of immunopathological damage. Conclusions The results of this study suggest that WE is a safe technology for disinfecting airborne pathogens. It demonstrated little to no effect on immune system activation and pathological outcomes in the intranasal challenge C57BL/6 mouse model. These findings not only support the potential use of WE as an effective and safe method for air disinfection but also highlight the value of the intranasal challenge of the C57BL/6 mouse model in providing significant immunopathological insights for assessing the inhalation of novel materials for potential use.

Abstract Background Conventional natural killer (cNK) cells play an important role in the innate immune response by directly killing infected and malignant cells and by producing pro- and anti-inflammatory cytokines. Studies on their role in malaria and its complications have resulted in conflicting results. Methods Using the commonly used anti-NK1.1 depletion antibodies (PK136) in an in-house optimized experimental model for malaria-associated acute respiratory distress syndrome (MA-ARDS), the role of cNK cells was investigated. Moreover, flow cytometry was performed to characterize different NK cell populations. Results While cNK cells were found to be dispensable in the development of MA-ARDS, the appearance of a NK1.1+ cell population was observed in the lungs upon infection despite depletion with anti-NK1.1. Detailed characterization of the unknown population revealed that this population consisted of a mixture of monocytes and macrophages that bind the anti-NK1.1 antibody in an aspecific way. This aspecific binding may occur via Fcγ receptors, such as FcγR4. In contrast, in vivo depletion using anti-NK1.1 antibodies was proved to be specific for cNK cells. Conclusion cNK cells are dispensable in the development of experimental MA-ARDS. Moreover, careful flow cytometric analysis, with a critical mindset in relation to potential aspecific binding despite the use of commercially available Fc blocking reagents, is critical to avoid misinterpretation of the results.

The COVID-19 pandemic remains a serious public health problem globally. During winter influenza seasons, more aggressive SARS-CoV-2 infections and fatalities have been documented, indicating that influenza co-infections may significantly impact the disease outcome of COVID-19. Both influenza and SARS-CoV-2 viruses share many similarities in their transmission and their cellular tropism for replication in the human respiratory tract. However, the complex intricacies and multi-faceted dynamics of how the two pathogens interact to ensure their survival in the same lung microenvironment are still unclear. In addition, clinical studies on influenza co-infections in COVID-19 patients do not provide conclusive evidence of how influenza co-infection mechanistically modifies disease outcomes of COVID-19. This review discusses various viral as well as host factors that potentially influence the survival or synergism of these two respiratory pathogens in the infected lung microenvironment. [ABSTRACT FROM AUTHOR]

The primary targets of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the lungs are type I pneumocytes, macrophages, and endothelial cells. We aimed to identify lung cells targeted by SARS-CoV-2 using viral nucleocapsid protein staining and morphometric features on patients with fatal COVID-19. We conducted a retrospective analysis of fifty-one autopsy cases of individuals who tested positive for SARS-CoV-2. Demographic and clinical information were collected from forensic reports, and lung tissue was examined for microscopic lesions and the presence of specific cell types. Half of the evaluated cohort were older than 71 years, and the majority were male (74.5%). In total, 24 patients presented diffuse alveolar damage (DAD), and 50.9% had comorbidities (56.9% obesity, 33.3% hypertension, 15.7% diabetes mellitus). Immunohistochemical analysis showed a similar pattern of infected macrophages, infected type I pneumocytes, and endothelial cells, regardless of the presence of DAD (p > 0.5). The immunohistochemical reactivity score (IRS) was predominantly moderate but without significant differences between patients with and without DAD (p = 0.633 IRS for type I pneumocytes, p = 0.773 IRS for macrophage, and p = 0.737 for IRS endothelium). The nucleus/cytoplasm ratio shows lower values in patients with DAD (median: 0.29 vs. 0.35), but the difference only reaches a tendency for statistical significance (p = 0.083). Our study confirms the presence of infected macrophages, type I pneumocytes, and endothelial cells with a similar pattern in patients with and without diffuse alveolar damage. [ABSTRACT FROM AUTHOR]

Background: Conventional natural killer (cNK) cells play an important role in the innate immune response by directly killing infected and malignant cells and by producing pro- and anti-inflammatory cytokines. Studies on their role in malaria and its complications have resulted in conflicting results. Methods: Using the commonly used anti-NK1.1 depletion antibodies (PK136) in an in-house optimized experimental model for malaria-associated acute respiratory distress syndrome (MA-ARDS), the role of cNK cells was investigated. Moreover, flow cytometry was performed to characterize different NK cell populations. Results: While cNK cells were found to be dispensable in the development of MA-ARDS, the appearance of a NK1.1+ cell population was observed in the lungs upon infection despite depletion with anti-NK1.1. Detailed characterization of the unknown population revealed that this population consisted of a mixture of monocytes and macrophages that bind the anti-NK1.1 antibody in an aspecific way. This aspecific binding may occur via Fcγ receptors, such as FcγR4. In contrast, in vivo depletion using anti-NK1.1 antibodies was proved to be specific for cNK cells. Conclusion: cNK cells are dispensable in the development of experimental MA-ARDS. Moreover, careful flow cytometric analysis, with a critical mindset in relation to potential aspecific binding despite the use of commercially available Fc blocking reagents, is critical to avoid misinterpretation of the results. [ABSTRACT FROM AUTHOR]

CD8+ T cells are critical to the adaptive immune response against viral pathogens. However, overwhelming antigen exposure can result in their exhaustion, characterised by reduced effector function, failure to clear virus, and the upregulation of inhibitory receptors, including programmed cell death 1 (PD-1). However, exhausted T cell responses can be "re-invigorated" by inhibiting PD-1 or the primary ligand of PD-1: PD-L1. Further, the absence of the type I interferon receptor IFNAR1 also results in T cell exhaustion and virus persistence in lymphocytic choriomeningitis virus Armstrong (LCMV-Arm)-infected mice. In this study, utilizing single- and double-knockout mice, we aimed to determine whether ablation of PD-1 could restore T cell functionality in the absence of IFNAR1 signalling in LCMV-Arm-infected mice. Surprisingly, this did not re-invigorate the T cell response and instead, it converted chronic LCMV-Arm infection into a lethal disease characterized by severe lung inflammation with an infiltration of neutrophils and T cells. Depletion of CD8+ T cells, but not neutrophils, rescued mice from lethal disease, demonstrating that IFNAR1 is required to prevent T cell exhaustion and virus persistence in LCMV-Arm infection, and in the absence of IFNAR1, PD-L1 is required for survival. This reveals an important interplay between IFNAR1 and PD-L1 with implications for therapeutics targeting these pathways. [ABSTRACT FROM AUTHOR]

Background: With increasing reports of accelerated and acute silicosis, PMF, and autoimmune disease among coal miners and silica‐exposed countertop workers, we present previously incompletely‐described pulmonary pathology of accelerated silicosis and correlations with mineralogy, radiography, and disease progression in 46 Texas oilfield pipe sandblasters who were biopsied between 1988 and 1995. Methods: Worker examinations included pulmonary function tests, chest X‐ray (CXR), high‐resolution computed tomography (HRCT), and Gallium‐67 scans. Quantitative mineralogic analysis of pulmonary parenchymal burden of silica, silicates, and metal particles used scanning electron microscopy with energy dispersive x‐ray spectroscopy (SEM EDS). Results: Workers had clinical deterioration after <10 years exposure in dusty workplaces. Although initial CXR was normal in 54%, Gallium‐67 scans were positive in 68% of those with normal CXR, indicating pulmonary inflammation. The histology of accelerated silicosis is diffuse interstitial infiltration of macrophages filled with weakly birefringent particles with or without silicotic nodules or alveolar proteinosis. Lung silica concentrations were among the highest in our database, showing a dose–response relationship with CXR, HRCT, and pathologic changes (macrophages, fibrosis, and silicotic nodules). Radiographic scores and diffusing capacity worsened during observation. Silica exposure was intensified, patients presented younger, with shorter exposure, more severe clinical abnormalities, higher lung particle burdens, and more rapid progression in a subset of patients exposed to recycled blasting sand. Conclusions: Accelerated silicosis may present with a normal CXR despite significant histopathology. Multivariable analyses showed silica, and not other particles, is the driver of observed radiologic, physiologic, and histologic outcomes. Eliminating this preventable disease requires higher physician, public health, and societal awareness. [ABSTRACT FROM AUTHOR]

Introduction: Workplace exposure to respirable crystalline silica (cSiO2) has been epidemiologically linked to lupus. Consistent with this, repeated subchronic intranasal cSiO2 instillation in lupus-prone NZBWF1 mice induces inflammation-/autoimmune-related gene expression, ectopic lymphoid tissue (ELT), autoantibody (AAb) production in the lung within 5 to 13 wk followed systemic AAb increases and accelerated onset and progression of glomerulonephritis within 13 to 17 wk. Interestingly, dietary docosahexaenoic acid (DHA) supplementation suppresses these pathologic effects, but the underlying molecular mechanisms remain unclear. Methods: This study aimed to test the hypothesis that dietary DHA supplementation impacts acute transcriptional and autoantibody responses in the lungs of female NZBWF1 mice 1 and 4 wk after a single high-dose cSiO2 challenge. Groups of mice were initially fed a control (Con) diet or a DHAcontaining diet (10 g/kg). Cohorts of Con- and DHA-fed were subjected to a single intranasal instillation of 2.5 mg cSiO2 in a saline vehicle (Veh), while a Confed cohort was instilled with Veh only. At 1 and 4 wk post-instillation (PI), we compared cSiO2's effects on innate-/autoimmune-related gene expression and autoantibody (AAb) in lavage fluid/lungs of Con- and DHA-fed mice and related these findings to inflammatory cell profiles, histopathology, cell death, and cytokine/chemokine production. Results: DHA partially alleviated cSiO2-induced alterations in total immune cell and lymphocyte counts in lung lavage fluid. cSiO2-triggered dead cell accumulation and levels of inflammation-associated cytokines and IFN stimulated chemokines were more pronounced in Con-fed mice than DHA-fed mice. Targeted multiplex transcriptome analysis revealed substantial upregulation of genes associated with autoimmune pathways in Con-fed mice in response to cSiO2 that were suppressed in DHA-fed mice. Pathway analysis indicated that DHA inhibited cSiO2 induction of proinflammatory and IFNregulated gene networks, affecting key upstream regulators (e.g., TNFa, IL-1b, IFNAR, and IFNg). Finally, cSiO2-triggered AAb responses were suppressed in DHA-fed mice. Discussion: Taken together, DHA mitigated cSiO2-induced upregulation of pathways associated with proinflammatory and IFN-regulated gene responses within 1 wk and reduced AAb responses by 4 wk. These findings suggest that the acute short-term model employed here holds substantial promise for efficient elucidation of the molecular mechanisms through which omega-3 PUFAs exert protective effects against cSiO2-induced autoimmunity. [ABSTRACT FROM AUTHOR]

Early-life respiratory syncytial virus (RSV) infection (eRSV) is one of the leading causes of serious pulmonary disease in children. eRSV is associated with higher risk of developing asthma and compromised lung function later in life. Cadmium (Cd) is a toxic metal, widely present in the environment and in food. We recently showed that eRSV reprograms metabolism and potentiates Cd toxicity in the lung, and our transcriptome-metabolome-wide study showed strong associations between S-palmitoyl transferase expression and Cd-stimulated lung inflammation and fibrosis signaling. Limited information is available on the mechanism by which eRSV reprograms metabolism and potentiates Cd toxicity in the lung. In the current study, we used a mouse model to examine the role of protein S-palmitoylation (Pr-S-Pal) in low dose Cd-elevated lung metabolic disruption and inflammation following eRSV. Mice exposed to eRSV were later treated with Cd (3.3 mg CdCl2/l) in drinking water for 6 weeks (RSV + Cd). The role of Pr-S-Pal was studied using a palmitoyl transferase inhibitor, 2-bromopalmitate (BP, 10 µM). Inflammatory marker analysis showed that cytokines, chemokines, and inflammatory cells were highest in the RSV + Cd group, and BP decreased inflammatory markers. Lung metabolomics analysis showed that pathways including phenylalanine, tyrosine and tryptophan, phosphatidylinositol and sphingolipid were altered across treatments. The BP antagonized metabolic disruption of sphingolipid and glycosaminoglycan metabolism by RSV + Cd, consistent with BP effect on inflammatory markers. This study shows that Cd exposure following eRSV has a significant impact on subsequent inflammatory response and lung metabolism, which is mediated by Pr-S-Pal, and warrants future research for a therapeutic target. [ABSTRACT FROM AUTHOR]

IntroductionMilitary personnel and local civilians at various deployment locations are plagued with serious health conditions. Evidence points to burn pit emissions as the cause of these pathologies; however, similar diseases are also caused by environmental exposures, smoking, genetic predispositions, or other comorbidities. Burn pits, which are large smoldering piles of refuse ignited with jet or diesel fuel, contain human and medical waste as well as paint, plastics, ammunition, and other materials—each of which can be attributed to health concerns in other industrial settings. Here we compare various pathologies attributable to toxic aerosol exposures and discuss distinct pathologies that may be linked to burn pit exposures.ObjectivesWe performed a literature review where we provide information on toxic exposures that may pose relevance to burn pit exposure and furthermore, highlight what is already known about burn pit exposures and what steps need to be taken to diagnose and correlate certain respiratory pathologies to chronic exposure from overseas burn pits.Data sourcesWe conducted searches through PubMed and Google Scholar to determine where gaps in our knowledge of burn pit exposure lie. Thorough review on jet-fuel properties and particulate matter were performed as supporting evidence of potential toxins from burn pit emissions.ResultsTo date, studies on burn pit emissions consist mainly of systematic reviews and discussions to address the problem, with very few acute-exposure studies and little to no chronic-exposure studies. We found that symptoms range from respiratory pathologies to neurological deficits, but treatment has been limited as medical facilities, such as the Veterans Administration (VA), require proof that a condition is service-connected.ConclusionsTo determine the effects of burn pit exposure on humans, chronic exposure to mimicked burn pit emissions is necessary to draw definitive conclusions between phenotypic differences in pathologies linked to exposure. By determining phenotypic differences, conclusions can be made about the pathologic origins, potentially leading to future diagnoses and treatments for veterans and affected civilians.

There is a reciprocal relationship between extracellular matrix (ECM) remodelling and inflammation that could be operating in the progression of severe COVID-19. To explore the immune-driven ECM remodelling in COVID-19, we in this explorative study analysed these interactions in hospitalised COVID-19 patients. RNA sequencing and flow analysis were performed on peripheral blood mononuclear cells. Inflammatory mediators in plasma were measured by ELISA and MSD, and clinical information from hospitalised COVID-19 patients (N=15) at admission was included in the analysis. Further, we reanalysed two publicly available datasets: (1) lung tissue RNA-sequencing dataset (N=5) and (2) proteomics dataset from PBCM. ECM remodelling pathways were enriched in PBMC from COVID-19 patients compared to healthy controls. Patients treated at the intensive care unit (ICU) expressed distinct ECM remodelling gene profiles compared to patients in the hospital ward. Several markers were strongly correlated to immune cell subsets, and the dysregulation in the ICU patients was positively associated with plasma levels of inflammatory cytokines and negatively associated with B-cell activating factors. Finally, our analysis of publicly accessible datasets revealed (i) an augmented ECM remodelling signature in inflamed lung tissue compared to non-inflamed tissue and (ii) proteomics analysis of PBMC from severe COVID-19 patients demonstrated an up-regulation in an ECM remodelling pathway. Our results may suggest the presence of an interaction between ECM remodelling, inflammation, and immune cells, potentially initiating or perpetuating pulmonary pathology in severe COVID-19.

Acute and chronic eosinophilic pneumonia (AEP and CEP) include a group of rare interstitial lung diseases characterized by peripheral blood eosinophilia, increased eosinophils in bronchoalveolar lavage fluid, or eosinophilic infiltration of lung parenchyma. AEP is characterized by rapid onset, fast response to steroid treatment, and no relapse. CEP is characterized by marked tissue and peripheral blood eosinophilia, rapid response to steroid therapy, and tendency to disease recurrence. In addition, we briefly describe other eosinophilic lung diseases that must be considered in differential diagnosis of AEP and CEP. Eosinophilic pneumonias may be idiopathic or due to known causes such as medications or environmental exposure. At variance with previous reviews on this topic, a particular look in this overview was directed at pathological findings and radiological patterns.

Mice develop pathology in the lungs as they age and this may be accelerated by a high calorie diet (HCD). ES-62 is a protein secreted by the parasitic worm Acanthocheilonema viteae that is immunomodulatory by virtue of covalently attached phosphorylcholine (PC) moieties. In this study, we show that weekly treatment of C57BL/6J mice with ES-62 protected against pathology in the lungs in male but not female mice fed a HCD from 10 weeks of age as shown by reductions in cellular infiltration and airway remodelling, particularly up to 160 days of age. ES-62 also reduced gene expression of the cytokines IL-4 and IL-17 and in addition the TLR/IL-1R adaptor MyD88, in the lungs of male mice although HCD-induced increases in these inflammatory markers were not detected until between 340 and 500 days of age. A combination of two drug-like ES-62 PCbased small molecule analogues (SMAs), produced broadly similar protective effects in the lungs of male mice with respect to both lung pathology and inflammatory markers, in addition to a decrease in HCD-induced IL-5 expression. Overall, our data show that ES-62 and its SMAs offer protection against HCDaccelerated pathological changes in the lungs during ageing. Given the targeting of Th2 cytokines and IL-17, we discuss this protection in the context of ES-62’s previously described amelioration of airway hyper-responsiveness in mouse models of asthma. [ABSTRACT FROM AUTHOR]

Background: Abnormal remodelling of the extracellular matrix (ECM) has generally been linked to pulmonary inflammation and fibrosis and may also play a role in the pathogenesis of severe COVID‐19. To further elucidate the role of ECM remodelling and excessive fibrogenesis in severe COVID‐19, we examined circulating levels of mediators involved in various aspects of these processes in COVID‐19 patients. Methods: Serial blood samples were obtained from two cohorts of hospitalised COVID‐19 patients (n = 414). Circulating levels of ECM remodelling mediators were quantified by enzyme immunoassays in samples collected during hospitalisation and at 3‐month follow‐up. Samples were related to disease severity (respiratory failure and/or treatment at the intensive care unit), 60‐day total mortality and pulmonary pathology after 3‐months. We also evaluated the direct effect of inactivated SARS‐CoV‐2 on the release of the different ECM mediators in relevant cell lines. Results: Several of the measured markers were associated with adverse outcomes, notably osteopontin (OPN), S100 calcium‐binding protein A12 and YKL‐40 were associated with disease severity and mortality. High levels of ECM mediators during hospitalisation were associated with computed tomography thorax pathology after 3‐months. Some markers (i.e. growth differential factor 15, galectin 3 and matrix metalloproteinase 9) were released from various relevant cell lines (i.e. macrophages and lung cell lines) in vitro after exposure to inactivated SARS‐CoV‐2 suggesting a direct link between these mediators and the causal agent of COVID‐19. Conclusion: Our findings highlight changes to ECM remodelling and particularly a possible role of OPN, S100A12 and YKL‐40 in the pathogenesis of severe COVID‐19. [ABSTRACT FROM AUTHOR]

Nontuberculous mycobacterial pulmonary disease (NTM-PD) is a potentially fatal infectious disease requiring long treatment duration with multiple antibiotics and against which there is no reliable cure. Among the factors that have hampered the development of adequate drug regimens is the lack of an animal model that reproduces the NTM lung pathology required for studying antibiotic penetration and efficacy. Given the documented similarities between tuberculosis and NTM immunopathology in patients, we first determined that the rabbit model of active tuberculosis reproduces key features of human NTM-PD and provides an acceptable surrogate model to study lesion penetration. We focused on clarithromycin, a macrolide and pillar of NTM-PD treatment, and explored the underlying causes of the disconnect between its favorable potency and pharmacokinetics and inconsistent clinical outcome. To quantify pharmacokinetic-pharmacodynamic target attainment at the site of disease, we developed a translational model describing clarithromycin distribution from plasma to lung lesions, including the spatial quantitation of clarithromycin and azithromycin in mycobacterial lesions of two patients on long-term macrolide therapy. Through clinical simulations, we visualized the coverage of clarithromycin in plasma and four disease compartments, revealing heterogeneous bacteriostatic and bactericidal target attainment depending on the compartment and the corresponding potency against nontuberculous mycobacteria in clinically relevant assays. Overall, clarithromycin's favorable tissue penetration and lack of bactericidal activity indicated that its clinical activity is limited by pharmacodynamic, rather than pharmacokinetic, factors. Our results pave the way toward the simulation of lesion pharmacokinetic-pharmacodynamic coverage by multidrug combinations to enable the prioritization of promising regimens for clinical trials.

The COVID-19 pandemic remains a serious public health problem globally. During winter influenza seasons, more aggressive SARS-CoV-2 infections and fatalities have been documented, indicating that influenza co-infections may significantly impact the disease outcome of COVID-19. Both influenza and SARS-CoV-2 viruses share many similarities in their transmission and their cellular tropism for replication in the human respiratory tract. However, the complex intricacies and multi-faceted dynamics of how the two pathogens interact to ensure their survival in the same lung microenvironment are still unclear. In addition, clinical studies on influenza co-infections in COVID-19 patients do not provide conclusive evidence of how influenza co-infection mechanistically modifies disease outcomes of COVID-19. This review discusses various viral as well as host factors that potentially influence the survival or synergism of these two respiratory pathogens in the infected lung microenvironment.

The primary targets of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the lungs are type I pneumocytes, macrophages, and endothelial cells. We aimed to identify lung cells targeted by SARS-CoV-2 using viral nucleocapsid protein staining and morphometric features on patients with fatal COVID-19. We conducted a retrospective analysis of fifty-one autopsy cases of individuals who tested positive for SARS-CoV-2. Demographic and clinical information were collected from forensic reports, and lung tissue was examined for microscopic lesions and the presence of specific cell types. Half of the evaluated cohort were older than 71 years, and the majority were male (74.5%). In total, 24 patients presented diffuse alveolar damage (DAD), and 50.9% had comorbidities (56.9% obesity, 33.3% hypertension, 15.7% diabetes mellitus). Immunohistochemical analysis showed a similar pattern of infected macrophages, infected type I pneumocytes, and endothelial cells, regardless of the presence of DAD (p > 0.5). The immunohistochemical reactivity score (IRS) was predominantly moderate but without significant differences between patients with and without DAD (p = 0.633 IRS for type I pneumocytes, p = 0.773 IRS for macrophage, and p = 0.737 for IRS endothelium). The nucleus/cytoplasm ratio shows lower values in patients with DAD (median: 0.29 vs. 0.35), but the difference only reaches a tendency for statistical significance (p = 0.083). Our study confirms the presence of infected macrophages, type I pneumocytes, and endothelial cells with a similar pattern in patients with and without diffuse alveolar damage.

Mice develop pathology in the lungs as they age and this may be accelerated by a high calorie diet (HCD). ES-62 is a protein secreted by the parasitic worm Acanthocheilonema viteae that is immunomodulatory by virtue of covalently attached phosphorylcholine (PC) moieties. In this study, we show that weekly treatment of C57BL/6J mice with ES-62 protected against pathology in the lungs in male but not female mice fed a HCD from 10 weeks of age as shown by reductions in cellular infiltration and airway remodelling, particularly up to 160 days of age. ES-62 also reduced gene expression of the cytokines IL-4 and IL-17 and in addition the TLR/IL-1R adaptor MyD88, in the lungs of male mice although HCD-induced increases in these inflammatory markers were not detected until between 340 and 500 days of age. A combination of two drug-like ES-62 PC-based small molecule analogues (SMAs), produced broadly similar protective effects in the lungs of male mice with respect to both lung pathology and inflammatory markers, in addition to a decrease in HCD-induced IL-5 expression. Overall, our data show that ES-62 and its SMAs offer protection against HCD-accelerated pathological changes in the lungs during ageing. Given the targeting of Th2 cytokines and IL-17, we discuss this protection in the context of ES-62’s previously described amelioration of airway hyper-responsiveness in mouse models of asthma.

Background: Antibody deficiencies result from reduced immunoglobulin levels and function, increasing susceptibility to, primarily, bacterial infection. Primary antibody deficiencies comprise intrinsic defects in B-cell physiology, often due to inherited errors. Hematological malignancies or B-cell suppressive therapy are major causes of secondary antibody deficiency. Although immunoglobulin replacement therapy (IGRT) reduces infectious burden in antibody deficiency patients, respiratory tract infections remain a significant health burden. We hypothesize that lung pathology and gastroesophageal reflux disease (GORD) increase the risk of pneumonia in antibody deficiency patients, as in the general population. Objective: For our cohort of patients with primary antibody deficiency and secondary antibody deficiency, we reviewed their respiratory infectious burden and the impact of lung pathologies and GORD. Methods: The medical records of 231 patients on IGRT at a tertiary referral center, from October 26, 2014, to February 19, 2021, were reviewed to determine microbial isolates from sputum samples and prevalence of common lung pathologies and GORD. Results: Haemophilus and Pseudomonas species represent a large infectious burden, being identified in 30.2% and 21.4% of sputum samples demonstrating growth, respectively; filamentous fungal and mycobacterial infections were rare. Diagnosed lung pathology increased the proportion of patients with Pseudomonas, Klebsiella, Stenotrophomonas, and Candida species isolated in their sputum, and diagnosed GORD increased the proportion with Enterobacter and Candida species isolated. Conclusions: Bacterial respiratory infectious burden remains in primary antibody deficiency and secondary antibody deficiency despite IGRT. Lung pathologies encourage growth of species less susceptible to IGRT, so specialist respiratory medicine input and additional treatments such as inhaled antibiotics are indicated to optimize respiratory outcomes.

Introduction: The use of chest Computed Tomography (CT) scans has significantly increased in recent times, and it is also considered the preferred investigation method in various cases, including occult pneumothorax and interstitial lung diseases. Aim: To assess the relationship between chest CT scan findings/outcomes, clinicians’ expectations, and their influence on treatment outcomes. Materials and Methods: The present retrospective analytical observational study was conducted in the Department of Radiodiagnosis and Respiratory Medicine at a tertiary-level hospital, Adesh Medical College and Hospital, Kurukshetra, Haryana, India. The findings of the selected chest CT scans were classified as normal, incidental, or pathological. The response of the consulting physicians to these scans was divided into three grades: highly expected, moderately expected, and unexpected. The impact of these scans on patients’ treatment was divided into three categories: major, minor, and none. The collected data were analysed using the Statistical Package for Social Sciences (SPSS) version 28.0, and the Chi-square test was used to assess the association between different variables. Results: The mean age of study participants was approximately 58±15 years. Out of the total 74 scans (each belonging to a different individual), the findings of the chest CT scans revealed that 59 (79.7%) scans were pathological, 11 (14.9%) were incidental, and only 4 (5.4%) were normal. The outcomes of these scans were highly expected in 42 (56.7%) cases, moderately expected in 25 (33.8%), and unexpected in 7 (9.5%). These scans had a major impact on the patient’s treatment course in 28 (37.8%) cases, minor impact in 40 (54%), and no influence in 6 (8.1%) cases. The Chi-square test showed a significant association between chest CT scan outcomes and clinicians’ expectations, chest CT scan outcomes and their influence on treatment, as well as clinicians’ expectations and the effect of scans on treatment. The p-value

CD8+ T cells are critical to the adaptive immune response against viral pathogens. However, overwhelming antigen exposure can result in their exhaustion, characterised by reduced effector function, failure to clear virus, and the upregulation of inhibitory receptors, including programmed cell death 1 (PD-1). However, exhausted T cell responses can be “re-invigorated” by inhibiting PD-1 or the primary ligand of PD-1: PD-L1. Further, the absence of the type I interferon receptor IFNAR1 also results in T cell exhaustion and virus persistence in lymphocytic choriomeningitis virus Armstrong (LCMV-Arm)-infected mice. In this study, utilizing single- and double-knockout mice, we aimed to determine whether ablation of PD-1 could restore T cell functionality in the absence of IFNAR1 signalling in LCMV-Arm-infected mice. Surprisingly, this did not re-invigorate the T cell response and instead, it converted chronic LCMV-Arm infection into a lethal disease characterized by severe lung inflammation with an infiltration of neutrophils and T cells. Depletion of CD8+ T cells, but not neutrophils, rescued mice from lethal disease, demonstrating that IFNAR1 is required to prevent T cell exhaustion and virus persistence in LCMV-Arm infection, and in the absence of IFNAR1, PD-L1 is required for survival. This reveals an important interplay between IFNAR1 and PD-L1 with implications for therapeutics targeting these pathways.

Introduction: The use of chest Computed Tomography (CT) scans has significantly increased in recent times, and it is also considered the preferred investigation method in various cases, including occult pneumothorax and interstitial lung diseases. Aim: To assess the relationship between chest CT scan findings/outcomes, clinicians' expectations, and their influence on treatment outcomes. Materials and Methods: The present retrospective analytical observational study was conducted in the Department of Radiodiagnosis and Respiratory Medicine at a tertiary-level hospital, Adesh Medical College and Hospital, Kurukshetra, Haryana, India. The findings of the selected chest CT scans were classified as normal, incidental, or pathological. The response of the consulting physicians to these scans was divided into three grades: highly expected, moderately expected, and unexpected. The impact of these scans on patients' treatment was divided into three categories: major, minor, and none. The collected data were analysed using the Statistical Package for Social Sciences (SPSS) version 28.0, and the Chi-square test was used to assess the association between different variables. Results: The mean age of study participants was approximately 58±15 years. Out of the total 74 scans (each belonging to a different individual), the findings of the chest CT scans revealed that 59 (79.7%) scans were pathological, 11 (14.9%) were incidental, and only 4 (5.4%) were normal. The outcomes of these scans were highly expected in 42 (56.7%) cases, moderately expected in 25 (33.8%), and unexpected in 7 (9.5%). These scans had a major impact on the patient's treatment course in 28 (37.8%) cases, minor impact in 40 (54%), and no influence in 6 (8.1%) cases. The Chi-square test showed a significant association between chest CT scan outcomes and clinicians' expectations, chest CT scan outcomes and their influence on treatment, as well as clinicians' expectations and the effect of scans on treatment. The p-value <0.05 was considered statistically significant for all three cases. Conclusion: Chest CT scans significantly impact the diagnostic and treatment pathway for patients. [ABSTRACT FROM AUTHOR]

The presence of the Tuberculosis (TB) disease-causing pathogen, Mycobacterium Tuberculosis (Mtb), induces the development of a pathological feature termed granuloma, which the host uses to contain the bacteria. However, the granuloma may dissociate resulting in detrimental caseation of the lung. The disease contributes to a growing global burden of lung function challenges, warranting for more understanding of the TB-induced immunopathology. The current study aims to explore in detail host factors that drive pathological features of TB contributing to extensive lung tissue destruction. Lung tissue sections obtained from patients undergoing surgical resection will be processed and analyzed using histopathological assays including Immunohistochemistry, Immunofluorescence, Hematoxylin and Eosin staining and Laser Capture Microdissection. The findings will provide key host factors that associate with exacerbated lung immunopathology during TB.

Background: Low body mass index (BMI) is associated with COPD, but temporal relationships between airflow obstruction (AO) development and emphysematous change are unclear. We investigated longitudinal changes in BMI, AO, and lung density throughout adulthood using data from the Framingham Offspring Cohort (FOC). Methods: BMI trajectories were modelled throughout adulthood in 4587 FOC participants from Exam 2 (mean age = 44), through Exam 9 (mean age = 71), in AO participants and non-AO participants (AO n = 1036), determined by spirometry, using fractional polynomial growth curves. This process was repeated for low lung density (LLD) and non LLD participants (LLD n = 225) determined by Computed Tomography. Spirometry decline was compared separately between tertiles of BMI in those aged <40 years and associations between fat and lean mass (measured using Dual Energy X-ray Absorptiometry, DEXA) and development of AO and LLD were also assessed. Additional analyses were performed with adjustment for smoking volume. Results: The BMI trajectory from 30 years of age was visually lower in the AO group than both non-AO smokers (non- 1/ FVC ratio in both sexes. Conclusion: Mean BMI is lower throughout adulthood in AO and LLD participants. Lower BMI is associated with a steeper decline in the ratio of FEV1/FVC. These findings suggest body mass may precede and potentially have a role in the development of COPD lung pathophysiology [ABSTRACT FROM AUTHOR]

Respiratory syncytial virus (RSV) infection causes serious pulmonary disease and death in high-risk infants and elderly. Cadmium (Cd) is a toxic environmental metal contaminant and constantly exposed to humans. Limited information is available on Cd toxicity after early-life respiratory virus infection. In this study, we examined the effects of low-dose Cd exposure following early-life RSV infection on lung metabolism and inflammation using mouse and fibroblast culture models. C57BL/6J mice at 8 days old were exposed to RSV 2 times with a 4-week interval. A subset of RSV-infected mice was subsequently treated with Cd at a low dose in drinking water (RSV infection at infant age [RSVinf]+Cd) for 16 weeks. The results of inflammatory marker analysis showed that the levels of cytokines and chemokines were substantially higher in RSVinf+Cd group than other groups, implying that low-dose Cd following early-life RSV infection enhanced lung inflammation. Moreover, histopathology data showed that inflammatory cells and thickening of the alveolar walls as a profibrotic signature were evident in RSVinf+Cd. The metabolomics data revealed that RSVinf+Cd-caused metabolic disruption in histamine and histidine, vitamin D and urea cycle, and pyrimidine pathway accompanying with mechanistic target of rapamycin complex-1 activation. Taken together, our study demonstrates for the first time that cumulative Cd exposure following early-life RSV infection has a significant impact on subsequent inflammation and lung metabolism. Thus, early-life respiratory infection may reprogram metabolism and potentiate Cd toxicity, enhance inflammation, and cause fibrosis later in life. [ABSTRACT FROM AUTHOR]

SARS‐CoV‐2 has evolved into a panel of variants of concern (VOCs) and constituted a sustained threat to global health. The wildtype (WT) SARS‐CoV‐2 isolates fail to infect mice, while the Beta variant, one of the VOCs, has acquired the capability to infect standard laboratory mice, raising a spreading risk of SARS‐CoV‐2 from humans to mice. However, the infectivity and pathogenicity of other VOCs in mice remain not fully understood. In this study, we systematically investigated the infectivity and pathogenicity of three VOCs, Alpha, Beta, and Delta, in mice in comparison with two well‐understood SARS‐CoV‐2 mouse‐adapted strains, MASCp6 and MASCp36, sharing key mutations in the receptor‐binding domain (RBD) with Alpha or Beta, respectively. Our results showed that the Beta variant had the strongest infectivity and pathogenicity among the three VOCs, while the Delta variant only caused limited replication and mild pathogenic changes in the mouse lung, which is much weaker than what the Alpha variant did. Meanwhile, Alpha showed comparable infectivity in lungs in comparison with MASCp6, and Beta only showed slightly lower infectivity in lungs when compared with MASCp36. These results indicated that all three VOCs have acquired the capability to infect mice, highlighting the ongoing spillover risk of SARS‐CoV‐2 from humans to mice during the continued evolution of SARS‐CoV‐2, and that the key amino acid mutations in the RBD of mouse‐adapted strains may be referenced as an early‐warning indicator for predicting the spillover risk of newly emerging SARS‐CoV‐2 variants. [ABSTRACT FROM AUTHOR]

Background: Lung ischemia reperfusion injury (IRI) is the principal cause of primary graft dysfunction (PGD) after lung transplantation, affecting short-term and long-term mortality post-transplantation. PANoptosis, a newly identified form of regulated cell death involving apoptosis, necroptosis, and pyroptosis, is now considered a possible cause of organ damage and IRI. However, the specific role of PANoptosis to the development of lung IRI following lung transplantation is still not fully understood., Methods: In this study, we identified differentially expressed genes (DEGs) by analyzing the gene expression data from the GEO database related to lung IRI following lung transplantation. PANoptosis-IRI DEGs were determined based on the intersection of PANoptosis-related genes and screened DEGs. Hub genes associated with lung IRI were further screened using Lasso regression and the SVM-RFE algorithm. Additionally, the Cibersort algorithm was employed to assess immune cell infiltration and investigate the interaction between immune cells and hub genes. The upstream miRNAs that may regulate hub genes and compounds that may interact with hub genes were also analyzed. Moreover, an external dataset was utilized to validate the differential expression analysis of hub genes. Finally, the expressions of hub genes were ultimately confirmed using quantitative real-time PCR, western blotting, and immunohistochemistry in both animal models of lung IRI and lung transplant patients., Results: PANoptosis-related genes, specifically interferon regulatory factor 1 (IRF1) and interleukin 1 alpha (IL1A), have been identified as potential biomarkers for lung IRI following lung transplantation. In mouse models of lung IRI, both the mRNA and protein expression levels of IRF1 and IL1A were significantly elevated in lung tissues of the IRI group compared to the control group. Moreover, lung transplant recipients exhibited significantly higher protein levels of IRF1 and IL1A in PBMCs when compared to healthy controls. Patients who experienced PGD showed elevated levels of IRF1 and IL1A proteins in their blood samples. Furthermore, in patients undergoing lung transplantation, the protein levels of IRF1 and IL1A were notably increased in peripheral blood mononuclear cells (PBMCs) compared to healthy controls. In addition, patients who developed primary graft dysfunction (PGD) exhibited even higher protein levels of IRF1 and IL1A than those without PGD. Furthermore, PANoptosis was observed in the lung tissues of mouse models of lung IRI and in the PBMCs of patients who underwent lung transplantation., Conclusions: Our research identified IRF1 and IL1A as biomarkers associated with PANoptosis in lung IRI, suggesting their potential utility as targets for diagnosing and therapeutically intervening in lung IRI and PGD following lung transplantation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Nobiletin (NOB), a polymethoxylated flavone isolated from citrus peels, is a promising dietary treatment for lung diseases, such as pulmonary fiborsis. In this work, the underlying mechanisms of NOB's preventative effect on pulmonary fibrosis were explored using bleomycin-exposed mice and IL-4-induced M2 polarization of the macrophages. Results showed that NOB treatment could significantly ameliorate lung fibrosis by suppressing pathological damages, collagen deposition, and fibroblat activation. Moreover, NOB obviously reduced the M2 macrophage-related proteins, including CD206, Arg1, and pro-fibrotic mediators such as TGF-β and CTGF, which might contribute to the antifibrosis effect of NOB. Network analysis of the differentially expressed genes in NOB-treated M2 macrophages showed that autophagy, mTOR signaling pathway, and AMPK signaling pathway might be involved in the effects of NOB. Further exploration illustrated that autophagy was enhanced in NOB-treated lung and M2 macrophages.The addition of 3MA, an autophagy inhibitor, could significantly weaken the effect of NOB on lung fibrosis and macrophage M2 polarization. Additionally, NOB also markedly decreased the expression of p-AMPK, p-mTOR, and p-P70S6K in the M2 macrophages and lung tissues of BLM-exposed mice. Compound C, an AMPK agonist, significantly suppressed NOB-induced activation of AMPK and mTOR signals, as well as its inhibitory effect on autophagy, M2 macrophages and lung fibrosis both in vitro and in vivo, supporting the requirement of AMPK-mTOR-mediated autophagy for the NOB's antifibrosis activity. Taken together, this study suggests that NOB ameliorates pulmonary fibrosis likely involving the inhibition of M2 macrophage via activating AMPK-mTOR-mediated autophagy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Idiopathic pulmonary fibrosis (IPF) is a progressive and incurable lung disease characterized by unknown etiology. This study employs robust ranking aggregation to identify consistent differential genes across multiple datasets, aiming to enhance prognostic evaluation and facilitate the development of more effective immunotherapy strategies for IPF. Using the GSE10667, GSE110147, and GSE24206 datasets, the analysis identifies 92 robust differentially expressed genes (DEGs), including SPP1, IGF1, ASPN, and KLHL13, highlighted as potential biomarkers through machine learning and experimental validation. Additionally, significant differences in immune cell types between IPF samples and controls, such as Plasma cells, Macrophages M0, Mast cells resting, T cells CD8, and NK cells resting, inform the construction of diagnostic and survival prediction models, demonstrating good applicability. These findings provide insights into IPF pathophysiology and suggest potential therapeutic targets., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Fibrosis is a pathological change mainly characterized by an increase of fibrous connective tissue and decrease of parenchymal cells. Its continuous progress may lead to the destruction of organ structure and function decline. An excess of alternatively activated M2 macrophages have been considered crucial candidates in the progression of fibrosis. Bone morphogenetic proteins (BMPs), a group of multifunctional growth factors, are essential for organ development and pathophysiological process, however, the roles that BMPs play in innate immune homeostasis in the development of fibrosis and the downstream signals have not been fully explored. In the current study, we firstly found that the expression of BMP4 was significantly down-regulated in human and mouse fibrosis samples. Then we investigated the effects of BMP4 on macrophage polarization in IL-4 environment and related molecular mechanisms, and found that BMP4 caused a decrease in polarized response towards M2, reflected in the expression of the markers Fizz1, Ym1 and Arg1, together with an inhibition in Stat6 phosphorylation. This relied on the Smad1/5/8 signaling, which had a crosstalk with Stat6. Moreover, the in vivo study showed that BMP4 treatment can reduce collagen deposition and delay the development of experimental pulmonary fibrosis in mice by inhibiting M2 macrophages through adoptive transfer experiment. These findings revealed a novel role of BMP4 in regulating macrophages, offering potential strategies for treating pulmonary fibrosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The eradication of tuberculosis remains a global challenge. Despite being the only licensed vaccine, Bacillus Calmette-Guérin (BCG) confers limited protective efficacy in adults and individuals with latent tuberculosis infections (LTBI). There is an urgent need to develop novel vaccines that can enhance the protective effect of BCG. Protein subunit vaccines have garnered significant research interest due to their safety and plasticity. Based on previous studies, we selected three antigens associated with LTBI (Rv2028c, Rv2029c, Rv3126c) and fused them with an immunodominant antigen Ag85A, resulting in the construction of a multistage protein subunit vaccine named A986. We evaluated the protective effect of recombinant protein A986 adjuvanted with MPL/QS21 as a booster vaccine for BCG against Mycobacterium tuberculosis (Mtb) infection in mice. The A986 + MPL/QS21 induced the secretion of antigen-specific Th1 (IL-2 + , IFN-γ + and TNF-α + ) and Th17 (IL-17A + ) cytokines in CD4 + and CD8 + T cells within the lung and spleen of mice, while also increased the frequency of central memory and effector memory T cells. Additionally, it also induced the enhanced production of IgG antibodies. Compared to BCG alone, A986 + MPL/QS21 boosting significantly augmented the proliferation of antigen-specific multifunctional T cells and effectively reduced bacterial load in infected mice. Taken together, A986 + MPL/QS21 formulation induced robust antigen-specific immune responses and provided enhanced protection against Mtb infection as a booster of BCG vaccine., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The pathogenesis of SSc pulmonary fibrosis is complex and prognosis is poor. In order to find biomarkers to provide assistance in the diagnosis and treatment of systemic sclerosis (SSc), this study explored the role of SSc-related differentially expressed circRNAs in the fibrosis process. This study explored whether circular RNA (circRNA) mediated the mTOR signaling pathway by interacting with the eukaryotic translation initiation factor eIF4E-binding protein 1 (4E-BP1), participated in a competing endogenous RNA (ceRNA) network, and regulated the mechanism of pulmonary fibrosis in systemic sclerosis (SSc). The results showed that the expression of mmu&#95;circ&#95;0005373 was reduced, and mmu&#95;circ&#95;0005373 may regulate the mTOR signaling pathway by inhibiting the interacting with 4E-BP1 protein in the lung of SSc mice, and promote fibrosis in SSc. Hsa&#95;circ&#95;0136255, which is homologous to mmu&#95;circ&#95;0005373, is also reduced in SSc peripheral blood mononuclear cells, and predicted to interact with 4E-BP1 protein. Hsa&#95;circ&#95;0136255/hsa-miR-330-3p/TNFAIP3 ceRNA network had biological significance in SSc, and correlated with clinical data, including high-resolution CT, average expiratory flow at 25% vital capacity, neutrophil count, lymphocyte percentage, standard deviation of red blood cell distribution width, coefficient of variation of red blood cell distribution width, platelet distribution width, glutamic transaminase, γ-glutamyl transpeptidase, lymphocyte percentage, basophils percentage, red blood cell, plateletcrit, cholinesterase, and mean corpuscular hemoglobin concentration. Hsa&#95;circ&#95;0136255, hsa-miR-330-3p, and TNFAIP3 may be used as biomarkers for clinical diagnosis and treatment of SSc., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Purpose: To investigate esketamine's impact on inflammation and oxidative stress in ventilated chronic obstructive pulmonary disease (COPD) rats, examining its regulatory mechanisms., Methods: Rats were divided into four groups: control group (Con), COPD model group (M), COPD model with saline treatment group (M+S), and COPD model with esketamine treatment group (M+K), with 12 rats in each group. After two months, all rats underwent anesthesia and mechanical ventilation. Group M+K received 5 mg/kg esketamine intravenously, while Group M+S received the same volume of saline. Lung tissues were collected for analysis two hours later, including airway peak pressure, wet-to-dry(W/D) ratio, lung permeability index(LPI), hematoxylin and eosin(H&E) staining, and transmission electron microscopy(TEM). Tumor necrosis factor-alpha(TNF-α), interleukin-6(IL-6), interleukin-8(IL-8), and interleukin-10(IL-10) levels were determined by enzyme-linked immunosorbent assay(ELISA); phosphorylated Nuclear Factor Kappa B(p-NF-κB), mitogen-activated protein kinase 14(p38), phosphorylated p38 (p-p38), c-Jun N-terminal kinase(JNK), and phosphorylated JNK (p-JNK) expressions by Western blotting and immunohistochemistry; and malondialdehyde(MDA), myeloperoxidase(MPO), and superoxide dismutase(SOD) levels were also measured by corresponding biochemical assays., Results: Lung specimens from groups M, M+S, and M+K manifested hallmark histopathological features of COPD. Compared with group Con, group M displayed increased peak airway pressure, W/D ratio, and LPI. In group M+K, compared with group M, esketamine significantly reduced the W/D ratio, LPI, and concentrations of pro-inflammatory cytokines TNF-α, IL-6, and IL-8 while concurrently elevating IL-10 levels. Furthermore, the treatment attenuated the activation of the NF-κB and MAPK pathways, indicated by decreased levels of p-NF-κB, p-p38, and p-JNK.Additionally, compared to group M, group M+K showed decreased MDA and MPO levels and increased SOD levels in lung tissue., Conclusion: Esketamine attenuates mechanical ventilation-induced lung injury in COPD rat models by inhibiting the MAPK/NF-κB signaling pathway and reducing oxidative stress., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Chronic obstructive pulmonary disease (COPD) is a common disease with high global morbidity and mortality. Macrophages release IL-1β and orchestrate airway inflammation in COPD. Previously, we explored the role of a new lncRNA, LincR-PPP2R5C, in regulating Th2 cells in asthma. Here, we established a murine model of COPD and explored the roles and mechanisms by which LincR-PPP2R5C regulates IL-1β in macrophages. LincR-PPP2R5C was highly expressed in pulmonary macrophages from COPD-like mice. LincR-PPP2R5C deficiency ameliorated emphysema and pulmonary inflammation, as characterized by reduced IL-1β in macrophages. Unexpectedly, in both lung tissues and macrophages, LincR-PPP2R5C deficiency decreased the expression of the IL-1β protein but not the IL-1β mRNA. Furthermore, we found that LincR-PPP2R5C deficiency increased the level of ubiquitinated IL-1β in macrophages, which was mediated by PP2A activity. Targeting PP2A with FTY720 decreased IL-1β and improved COPD. In conclusion, LincR-PPP2R5C regulates IL-1β ubiquitination by affecting PP2A activity in macrophages, contributing to the airway inflammation and emphysema in a murine model of COPD. PP2A and IL-1β ubiquitination in macrophages might be new therapeutic avenues for COPD therapy., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Acute lung injury (ALI) is a severe clinical condition in the intensive care units, and obesity is a high risk of ALI. Paradoxically, obese ALI patients had better prognosis than non-obese patients, and the mechanism remains largely unknown., Methods: Mouse models of ALI and diet-induced-obesity (DIO) were used to investigate the effect of exosomes derived from adipose tissue. The adipose-derived exosomes (ADEs) were isolated by ultracentrifugation, and the role of exosomal miRNAs in the ALI was studied., Results: Compared with ADEs of control mice (C-Exo), ADEs of DIO mice (D-Exo) increased survival rate and mitigated pulmonary lesions of ALI mice. GO and KEGG analyses showed that the target genes of 40 differentially expressed miRNAs between D-Exo and C-Exo were mainly involved with inflammation, apoptosis and cell cycle. Furthermore, the D-Exo treatment significantly decreased Ly6G + cell infiltration, down-regulated levels of pro-inflammatory cytokines (IL-6, IL-12, TNF-α, MCP-1) and chemokines (IL-8 and MIP-2), reduced pulmonary apoptosis and arrest at G 0 G 1 phase (P < 0.01). And the protective effects of D-Exo were better than those of C-Exo (P < 0.05). Compared with the C-Exo mice, the levels of miR-16-5p and miR-335-3p in the D-Exo mice were significantly up-regulated (P < 0.05), and the expressions of IKBKB and TNFSF10, respective target of miR-16-5p and miR-335-3p by bioinformatic analysis, were significantly down-regulated in the D-Exo mice (P < 0.05)., Conclusions: Exosomes derived from adipose tissue of DIO mice are potent to attenuate LPS-induced ALI, which could be contributed by exosome-carried miRNAs. Our data shed light on the interaction between obesity and ALI., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Objective: Although some studies suggested that metabolic abnormalities may contribute to the development of pulmonary fibrosis, there are no studies that have reported a clear causal relationship between them, and the aim of this study was to explore the causal relationship between plasma metabolites and pulmonary fibrosis using Mendelian randomization (MR) combined with metabolomics analysis., Methods: Firstly, we explored the causal relationship between 1400 metabolites and pulmonary fibrosis using MR analysis, and detected plasma metabolites in mice with pulmonary fibrosis using metabolomics technology, thus validating the results of MR analysis. In addition, we again used MR to explore the causal relationship between the results of the differential metabolite KEGG in metabolomics and pulmonary fibrosis., Results: A total of 52 metabolites were screened for association with pulmonary fibrosis in the MR analysis of 1400 plasma metabolites with pulmonary fibrosis, based on P < 0.05 for the IVW method, with consistent OR directions for all methods. Four of them were validated in the plasma of mice with pulmonary fibrosis, namely carnitine c18:2 levels (negative correlation), Glutamine degradant levels (positive correlation), Propionylcarnitine (c3) levels (negative correlation), carnitine to palmitoylcarnitine (c16) ratio (negative correlation). In addition, KEGG analysis of plasma differential metabolites revealed that the signaling pathway of biosynthetic of unsaturated fatty acids was most affected in mice with pulmonary fibrosis, and MR analysis showed that imbalance in the ratio of monounsaturated fatty acids was significantly associated with pulmonary fibrosis., Conclusions: Our study suggests that abnormal fatty acid levels due to reduced levels of carnitine-like metabolites, and an imbalance in the ratio of monounsaturated, promote the development of pulmonary fibrosis. This study reveals the marker metabolites and metabolic pathways affecting the development of pulmonary fibrosis to provide a basis for the development of new drugs for the treatment of pulmonary fibrosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The complex pathogenesis of lung ischemia-reperfusion injury (LIRI) was examined in a murine model, focusing on the role of pyroptosis and its exacerbation of lung injury. We specifically examined the levels and cellular localization of pyroptosis within the lung, which revealed alveolar macrophages as the primary site. The inhibition of pyroptosis by VX-765 reduced the severity of lung injury, underscoring its significant role in LIRI. Furthermore, the therapeutic potential of β-hydroxybutyrate (β-OHB) in ameliorating LIRI was examined. Modulation of β-OHB levels was evaluated by ketone ester supplementation and 3-hydroxybutyrate dehydrogenase 1 (BDH-1) gene knockout, along with the manipulation of the SIRT1-FOXO3 signaling pathway using EX-527 and pCMV-SIRT1 plasmid transfection. This revealed that β-OHB exerts lung-protective and anti-pyroptotic effects, which were mediated through the upregulation of SIRT1 and the enhancement of FOXO3 deacetylation, leading to decreased pyroptosis markers and lung injury. In addition, β-OHB treatment of MH-S cells in vitro showed a concentration-dependent improvement in pyroptosis, linking its therapeutic benefits to specific cell mechanisms. Overall, this study highlights the significance of alveolar macrophage pyroptosis in the exacerbation of LIRI and indicates the potential of β-OHB in mitigating injury by modulating the SIRT1-FOXO3 signaling pathway., (© 2024 Federation of American Societies for Experimental Biology.)

Ethnopharmacological Relevance: Dendrobium officinale Kimura et Migo, known as "Tiepi Shihu" in traditional Chinese medicine, boasts an extensive history of medicinal use documented in the Chinese Pharmacopoeia. "Shen Nong Ben Cao Jing" records D. officinale as a superior herbal medicine for fortifying "Yin" and invigorating the five viscera. Erianin, a benzidine compound, emerges as a prominent active constituent derived from D. officinale, with the pharmacological efficacy of D. officinale closely linked to the anti-inflammatory properties of erianin., Aim of the Study: Acute lung injury (ALI) is a substantial threat to global public health, while P-selectin stands out as a promising novel target for treating acute inflammatory conditions. This investigation aims to explore the therapeutic potential of erianin in ALI treatment and elucidate the underlying mechanisms., Experimental Design: The effectiveness of erianin in conferring protection against ALI was investigated through comprehensive histopathological and biochemical analyses of lung tissues and bronchoalveolar lavage fluid (BALF) in an in vivo model of LPS-induced ALI in mice. The impact of erianin on fMLP-induced neutrophil chemotaxis was quantitatively assessed using the Transwell and Zigmond chamber, respectively. To determine the therapeutic target of erianin and elucidate their binding capability, a series of sophisticated assays were employed, including drug affinity responsive target stability (DARTS) assay, cellular thermal shift assay (CETSA), and molecular docking analyses., Results: Erianin demonstrated a significant alleviation of LPS-induced acute lung injury, characterized by reduced total cell and neutrophil counts and diminished total protein contents in BALF. Moreover, erianin exhibited a capacity to decrease proinflammatory cytokine production in both lung tissues and BALF. Notably, erianin effectively suppressed the activation of NF-κB signaling in the lung tissues of LPS- challenged mice; however, it did not exhibit in vitro inhibitory effects on inflammation in LPS-induced human pulmonary microvascular endothelial cells (HPMECs). Additionally, erianin blocked the adhesion and rolling of neutrophils on HPMECs. While erianin did not influence endothelial P-selectin expression or cytomembrane translocation, it significantly reduced the ligand affinity between P-selectin and P-selectin glycoprotein ligand-1 (PSGL-1)., Conclusions: Erianin inhibits P-selectin-mediated neutrophil adhesion to activated endothelium, thereby alleviating ALI. The present study highlights the potential of erianin as a promising lead for ALI treatment., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Ethnopharmacological Relevance: The traditional Chinese medicine (TCM) Xiaoer-Feire-Qing granules (XEFRQ) has been used to treat pyretic pulmonary syndrome (PPS) in children for many years. The function of the lungs is considered to be closely related to the large intestine in TCM., Purpose: We aimed to investigate the effects of XEFRQ on PPS and the underlying mechanisms via network pharmacology and animal experiments., Methods: The TCMSP platform was used to identify the ingredients and potential targets of XEFRQ. The GeneCards, OMIM, and TTD databases were used to predict PPS-associated targets. Cytoscape 3.9.1 was employed to construct the protein-protein interaction network, and target prediction was performed by GO and KEGG analyses. For the animal experiment, a PPS model was constructed by three cycles of nasal drip of Streptococcus pneumoniae (STP; 0.5 mL/kg). The animals were randomly divided into the following four groups according to their weight (n = 10 rats per group): the blank group, the model group, the XEFRQ-L (16.3 g/kg) group, and the XEFRQ-H (56.6 g/kg) group. Rats in the blank group and the model group were given 0.5% CMC-Na by gavage. The general conditions of the rats were observed, and their food-intake, body weight, and body temperature were recorded for 14 days. After the intervention of 14 days, serum was collected to detect inflammatory cytokines (TNF-α, IL-1β, and PGE2) and neurotransmitters (5-HT, SP, and VIP). H&E staining was used to observe the pathological morphology of lung and colon tissue. AQP3 expression was detected by Western blot. In addition, the gut microbiota in cecal content samples were analyzed by 16S rDNA high-throughput sequencing., Results: Our network analysis revealed that XEFRQ may alleviate PPS injury by affecting the levels of inflammatory cytokines and neurotransmitters and mitigating STP-induced PPS.In vivo validation experiments revealed that XEFRQ improved STP-induced PPS and reduced the expression of inflammatory cytokines and neurotransmitters. Notably, XEFRQ significantly decreased the protein expression levels of AQP3, which was associated with dry stool. Our gut microbiota analysis revealed that the relative abundance of [Eubacterium]&#95;ruminantium&#95;group, Colidextribacter, Romboutsia, and Oscillibacter was decreased, which means XEFRQ exerts therapeutic effects against PPS associated with these bacteria., Conclusion: Our results demonstrate that XEFRQ alleviates PPS by affecting the lungs and intestines, further guiding its clinical application., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Ethnopharmacological Relevance: Various components of Lonicera japonica Thunb. (LJT) exhibit pharmacological activities, including anti-inflammatory and antioxidant effects. Nevertheless, the relationship between LJT and ferroptosis remains largely unexplored., Aim of the Study: The purpose of this research was to look into the role of LJT in regulating LPS-induced ferroptosis in ALI and to compare the effects of different parts of LJT., Materials and Methods: We established a mice ALI model by treating with LPS. Administered mice with different doses of Lonicerae Japonicae Flos (LJF), Lonicera Japonica Leaves (LJL) and Lonicerae Caulis (LRC) extracts, respectively. The levels of IL-6, IL-1β, TNF-α, IL-4, IL-10, and PGE2 in bronchoalveolar lavage fluid (BALF) were measured using enzyme-linked immunosorbent assay. Furthermore, the concentrations of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), reactive oxygen species (ROS), and total ferrous ions (Fe 2+ ) in lung tissues were evaluated. Hematoxylin and eosin staining was conducted to examine the morphological structure of lung tissues. Transmission electron microscopy was used to investigate the ultrastructural morphology of mitochondria. Furthermore, the effects of LJT were evaluated via immunohistochemical staining, western blotting, and quantitative real-time polymerase chain reaction analyses. Finally, employing molecular docking and molecular dynamics research techniques, we aimed to identify crucial components in LJT that might inhibit ferroptosis by targeting nuclear factor erythroid 2-related factor 2 (Nrf2) and glutathione peroxidase 4 (GPX4)., Results: We observed that pretreatment with LJT significantly mitigated LPS-induced lung injury and suppressed ferroptosis. This was supported by reduced accumulation of pro-inflammatory cytokines, ROS, MDA, and Fe 2+ , along with increased levels of anti-inflammatory cytokines, SOD, GSH, Nrf2, and GPX4 in the lung tissues of ALI mice. Luteolin-7-O-rutinoside, apigenin-7-O-rutinoside, and amentoflavone in LJT exhibit excellent docking effects with key targets of ferroptosis, Nrf2 and GPX4., Conclusions: Pretreatment with LJT may alleviate LPS-induced ALI, possibly by suppressing ferroptosis. Our initial results indicate that LJT activates the Nrf2/GPX4 axis, providing protection against ferroptosis in ALI. This finding offers a promising therapeutic candidate for ALI treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Ethnopharmacological Relevance: Sepsis poses one of the biggest public health problems, necessitating the search for new therapeutic alternatives. For centuries, propolis has been widely used in folk medicine to treat various inflammatory and infectious diseases. Given its extensive use, it has excellent potential as an adjuvant treatment for patients with sepsis., Objective: This study evaluated prophylactic treatment with standardized propolis extract (EPP-AF®) and followed the prognosis of sepsis induced by ligation and cecal ligation and puncture (CLP)., Methods: Initially, for survival assessment, Swiss mice were separated into five groups: Sham (false operated), control (PBS), ATB (received antibiotic, 8 mg/kg), P10 (received EPP-AF®, 10 mg/kg), and P100 (received EPP-AF®, 100 mg/kg). The animals received PBS, antibiotic, or EPP-AF® by the subcutaneous route 6 h before the CLP procedure. Animal survival was assessed every 12 h for five days when all of them were euthanized., Results: We show that the treatment with EPP-AF® significantly increased the life expectancy of animals with sepsis compared to the control group. Interestingly, prophylactic treatment with EPP-AF® showed no effect on the number of colony-forming units in the peritoneum, blood, or lung. However, there was a decrease in cellular influx in the peritoneum. This alteration was unrelated to the number of bone marrow cells or the differential counting of peripheral blood cells. The coagulogram remained unchanged, including the number of platelets and prothrombin time-activated partial thromboplastin time. However, the inflammatory infiltrate and bleeding in the lung tissue were lower in the animals that received EPP-AF®., Conclusion: Thus, it was possible to conclude that prophylactic treatment with EPP-AF® preserved the lung parenchyma, resulting in an increased lifespan of mice with sepsis. It can be a helpful adjuvant in prophylactic treatment with antibiotics in presurgical conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Ethnopharmacological Relevance: Ginkgo biloba leaf and seed have been traditionally used in ancient China for the treatment of cough and asthma. However, there is limited literature available on the anti-COPD effects and mechanisms of Ginkgo biloba., Aims of the Study: The aim of this study was to comprehensively investigate the therapeutic potential of ginkgo extracts in COPD through a combination of in vivo and in vitro functional experiments. Transcriptomic analyses were also employed to uncover novel molecular mechanisms underlying the therapeutic effects of ginkgetin in COPD., Materials and Methods: The therapeutic efficacy of ginkgo extracts was assessed in a COPD model. The anti-inflammatory effects of ginkgetin and its underlying molecular mechanisms were examined in A549 cells treated with cigarette smoke extract (CSE). Additionally, transcriptomic analyses were conducted to identify novel molecular pathways influenced by ginkgetin. These findings were further validated using quantitative real-time polymerase chain reaction (qPCR) and Western blot techniques., Results: The ethyl acetate extract of Ginkgo biloba L. seeds and ginkgetin treatment significantly reduced cytokine production in COPD mice. Following drug administration, lung function improved in different groups. The transcriptome data strongly supports the inhibitory effect of ginkgetin on CSE-induced inflammation through the downregulation of the c/EBPβ signaling pathway and subsequent inhibition of CCL2 expression., Conclusion: Our results demonstrate that ginkgetin, one of the biflavones found in Ginkgo biloba, exhibits inhibitory effects on smoke-induced airway inflammation. This effect is achieved through the downregulation of the c/EBPβ signaling pathway and the reduction of CCL2 expression., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Headings Ethnopharmacological Relevance: Sangbaipi Decoction (SBPD) is an effective treatment for lung diseases caused by phlegm-heat obstruction according to Jingyue Quanshu, and soothes panting by purging the lung meridian. It is composed of anti-pyretic herbs (e.g., Scutellaria baicalensis Georgi and Coptis chinensis Franch.) and antitussive herbs (e.g., Cortex Mori and Armeniacae Semen Amarum). Therefore, we hypothesized that SBPD has therapeutic effects on lung injury caused by influenza virus., Aim of the Study: This study aimed to explore anti-influenza activity, active components, and mechanisms of SBPD., Materials and Methods: The anti-influenza activities of SBPD were determined in 48 h drug-treated MDCK cell model using CPE and plaque reduction assays, and 24 h drug-treated A549 cells using qRT-PCR. The in vivo efficacy of SBPD (1.0 g/kg/day and 0.5 g/kg/day) was evaluated in PR8 infected BALB/c mice. The chemical component was assessed through HPLC-Q-TOF MS/MS analysis. Network pharmacology was built via TCMSP, GeneCards, DisgeNet, OMIM, DrugBank databases, and Cytoscape software. Additionally, TOA, HI and NAI assays were employed to investigate impact on the virus replication cycle with different concentrations of SBPD (2.5 mg/mL, 1.25 mg/mL, or 0.625 mg/mL)., Results: In MDCK infected with viruses A/PR/8/34, A/Hong Kong/1/68, or A/California/4/2009, the IC 50 values of SBPD were 0.80 mg/mL, 1.20 mg/mL, and 1.25 mg/mL. In A549 cells, SBPD treatment reduced cytokine expression (e.g., TNF-α, IL-6, IL-1β) (p < 0.05). In PR8 infected BALB/c mice, SBPD improved the survival rate of infected mice, reduced lung index (p < 0.05), protected lung tissue from pathological damage, and regulated cytokine overexpression (p < 0.05). 29 components of SBPD were identified in SBPD treated mouse serum including some phytochemicals targeting influenza proteins. HI and NAI assays suggested the potential antiviral mechanism of SBPD through inhibition of HA and NA., Conclusion: This study is the first to demonstrate the anti-influenza and the anti-inflammatory effects of SBPD in vitro and in vivo. Its major anti-influenza phytochemicals were explored and its inhibitory effects on HA and NA protein were proved. It provides more options for anti-influenza drug discovery., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Tripartite motif (Trim) 31 is important for numerous inflammatory diseases. However, whether Trim31 regulates airway inflammation in asthma remains undetermined. The present work explored the role of Trim31 in airway inflammation in asthmatic mice established by ovalbumin (OVA) stimulation. Trim31 expression was markedly downregulated in the lungs of asthmatic mice. Compared with wild-type (WT) mice, Trim31 -/- mice showed more severe pathological changes accompanied by increased inflammatory cell infiltration after OVA induction. House dust mite (HDM) stimulation evoked airway epithelial cell injury and inflammation, which were exacerbated by Trim31 silencing or attenuated by Trim31 overexpression. Further examination revealed that Trim31 deficiency exacerbated the activation of the NLRP3 inflammasome in OVA-induced asthmatic mice and HDM-stimulated airway epithelial cells. The inhibition of NLRP3 markedly diminished the Trim31 silencing-mediated enhancement of HDM-induced injury and inflammation in airway epithelial cells. In conclusion, this work demonstrates that Trim31 acts as a crucial mediator of airway inflammation in asthma. Trim31 deficiency may contribute to the progression of asthma by increasing NLRP3 inflammasome activation, suggesting that Trim31 is a potential therapeutic target for asthma., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Pulmonary fibrosis is a progressive disease with high incidence and poor prognosis. It is urgent to explore new therapeutic methods for pulmonary fibrosis. As a new treatment method, gene therapy has attracted more and more attention. CCDC59 is a transcriptional coactivator of SP-B and SP-C. Our study mainly aims to explore the effect of overexpression of CCDC59 gene in pulmonary fibrosis of mice., Methods: CCDC59 overexpressing lentivirus was constructed and then concentrated. RT-qPCR, Western blotting, and immunofluorescence assays were used to detect the expression of CCDC59, SP-B and SP-C protein in cell line and lung tissues after infected with lentivirus. Immunohistochemical staining and hematoxylin-eosin staining assays were used to assess the degree of fibrosis and ELISA assay was used to detect the concentrations of inflammatory factors, SP-B, and SP-C in bronchoalveolar lavage fluid of mice. Dynamic changes of mice lung function at various time points were assessed by lung function test assay. HIPPO pathway and proliferation capacity of alveolar type II epithelial cells were evaluated by immunofluorescence staining and Western blotting., Results: Results showed that endotracheal instillation of CCDC59 overexpressed lentivirus significantly alleviated bleomycin-induced inflammation and pulmonary fibrosis in mice. Overexpression of CCDC59 protein in type II alveolar epithelial cells can enhance the expression of SP-B and SP-C. Overexpression of CCDC59 protein significantly protected against pulmonary inflammatory response and improved lung function of mice. Overexpression of CCDC59 protein significantly alleviated the hyperactivation of HIPPO pathway and increased the proliferative capacity of type II alveolar epithelial cells in lung., Conclusion: CCDC59 can alleviate inflammation and pulmonary fibrosis in mice by upregulating the expression of SP-B and SP-C in type II alveolar epithelial cells and alleviating the hyperactivation of HIPPO pathway. Our study offers a new potential treatment for pulmonary fibrosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)