Mitigation of acute lung injury by human bronchial epithelial cell-derived extracellular vesicles via ANXA1-mediated FPR signaling

Acute lung injury (ALI) is characterized by respiratory failure resulting from the disruption of the epithelial and endothelial barriers as well as immune system. In this study, we evaluated the therapeutic potential of airway epithelial cell-derived extracellular vesicles (EVs) in maintaining lung homeostasis. We isolated human bronchial epithelial cell-derived EVs (HBEC-EVs), which endogenously express various immune-related surface markers and investigated their immunomodulatory potential in ALI. In ALI cellular models, HBEC-EVs demonstrated immunosuppressive effects by reducing the secretion of proinflammatory cytokines in both THP-1 macrophages and HBECs. Mechanistically, these effects were partially ascribed to nine of the top 10 miRNAs enriched in HBEC-EVs, governing toll-like receptor-NF-κB signaling pathways. Proteomic analysis revealed the presence of proteins in HBEC-EVs involved in WNT and NF-κB signaling pathways, pivotal in inflammation regulation. ANXA1, a constituent of HBEC-EVs, interacts with formyl peptide receptor (FPR)2, eliciting anti-inflammatory responses by suppressing NF-κB signaling in inflamed epithelium, including type II alveolar epithelial cells. In a mouse model of ALI, intratracheal administration of HBEC-EVs reduced lung injury, inflammatory cell infiltration, and cytokine levels. Collectively, these findings suggest the therapeutic potential of HBEC-EVs, through their miRNAs and ANXA1 cargo, in mitigating lung injury and inflammation in ALI patients.

Predictors of in-hospital mortality in elderly unvaccinated patients during SARS-CoV-2 Alpha variants epidemic

Background

COVID-19, caused by SARS-CoV-2, has caused a global pandemic. This study aimed to identify predictors of in-hospital mortality in unvaccinated elderly patients with COVID-19 by comparing various predictive factors between the survivors and non-survivors.

Methods

We retrospectively selected 132 unvaccinated patients aged over 65 years with COVID-19 at a hospital in Kanagawa, Japan, during SARS-CoV-2 Alpha variants epidemic. We compared the clinical characteristics, laboratory and radiological findings, treatment, and complications of the survivors and non-survivors. In logistic regression analysis, variables that were significant in the univariate analysis were subjected to multivariate analysis using the variable increase method.

Results

There were 119 and 13 patients in the survivor and non-survivor groups, respectively. Multivariate regression revealed increasing odds with the presence of ARDS and DIC (odd ratio (OR) = 16.35, 34.36; P=0.002, 0.001, respectively) and prolonged hospital stay (OR = 1.17; P=0.004).

Conclusions

We found the complications of ARDS and DIC and hospital length of stay to be independent predictors of in-hospital mortality in elderly unvaccinated patients with COVID-19. Establishing treatments and prevention methods for ARDS and DIC could result in lower mortality rates.

IL-27 regulates the differentiation of follicular helper NKT cells via metabolic adaptation of mitochondria

Invariant natural killer T (iNKT) cells are innate-like T lymphocytes that express an invariant T cell receptor α chain and contribute to bridging innate and acquired immunity with rapid production of large amounts of cytokines after stimulation. Among effecter subsets of iNKT cells, follicular helper NKT (NKTFH) cells are specialized to help B cells. However, the mechanisms of NKTFH cell differentiation remain to be elucidated. In this report, we studied the mechanism of NKTFH cell differentiation induced by pneumococcal surface protein A and α-galactosylceramide (P/A) vaccination. We found that Gr-1+ cells helped iNKT cell proliferation and NKTFH cell differentiation in the spleen by producing interleukin-27 (IL-27) in the early phase after vaccination. The neutralization of IL-27 impaired NKTFH cell differentiation, which resulted in compromised antibody production and diminished protection against Streptococcus pneumoniae infection by the P/A vaccine. Our data indicated that Gr-1+ cell-derived IL-27 stimulated mitochondrial metabolism, meeting the energic demand required for iNKT cells to differentiate into NKTFH cells. Interestingly, Gr-1+ cell-derived IL-27 was induced by iNKT cells via interferon-γ production. Collectively, our findings suggest that optimizing the metabolism of iNKT cells was essential for acquiring specific effector functions, and they provide beneficial knowledge on iNKT cell-mediated vaccination-mediated therapeutic strategies.

Clinical and imaging features of interstitial lung disease in cancer patients treated with trastuzumab deruxtecan

BACKGROUND

Interstitial lung disease/pneumonitis (ILD/pneumonitis) has been identified as a drug-related adverse event of special interest of trastuzumab deruxtecan (T-DXd), but there were a few reports of T-DXd-related ILD/pneumonitis in clinical practice.

METHODS

Between May 25, 2020 (the launch of T-DXd in Japan) and February 24, 2022, there were 287 physician-reported potential ILD/pneumonitis cases from the Japanese post-marketing all-case surveillance. By February 27, 2022, an independent adjudication committee assessed 138 cases and adjudicated 130 cases as T-DXd-related ILD/pneumonitis. The clinical features and imaging characteristics of these cases were evaluated.

RESULTS

The majority of adjudicated T-DXd-related ILD/pneumonitis cases were grade 1 or 2 (100/130, 76.9%). The most common radiological pattern types observed were organizing pneumonia patterns (63.1%), hypersensitivity pneumonitis patterns (16.9%), and diffuse alveolar damage (DAD) patterns (14.6%). Eleven cases (8.5%) from 130 resulted in death; the majority of these (8/11, 72.7%) had DAD patterns. The overall proportion of recovery (including the outcomes of recovered, recovered with sequelae, and recovering) was 76.9%, and the median time to recovery was 83.5 days (interquartile range: 42.25-143.75 days). Most cases (59/71, 83.1%) that were treated with corticosteroids were considered responsive to treatment.

CONCLUSIONS

This is the first report to evaluate T-DXd-related ILD/pneumonitis cases in clinical practice. Our findings are consistent with previous reports and suggest that patients with DAD patterns have poor outcomes. Evaluation of a larger real-world dataset may further identify predictors of clinical outcome.

Simultaneous diagnosis of allergic bronchopulmonary aspergillosis and Mycobacterium avium complex lung disease

Allergic bronchopulmonary aspergillosis (ABPA) and Mycobacterium avium complex lung disease (MAC-LD) often coexist because bronchiectasis, caused by ABPA or MAC, might be an important predisposing factor for both conditions. Here, we describe a man with asthma symptoms who had centrilobular small nodules and mucoid impaction on chest CT. We diagnosed the patient with simultaneous ABPA and MAC-LD on the basis of bronchoscopy findings. Itraconazole monotherapy led to substantial clinical improvement, avoiding the adverse effects of systemic corticosteroids. Sputum culture conversion of MAC was achieved after switching from itraconazole monotherapy to combination therapy comprising clarithromycin, rifampicin and ethambutol. ABPA recurred but was controlled by reinitiation of itraconazole. Overall, corticosteroid management was avoided for 38 months. Itraconazole monotherapy may be selected as initial treatment for ABPA with chronic infection, including MAC.

Cohort study to evaluate prognostic factors in idiopathic pulmonary fibrosis patients introduced to oxygen therapy

While high-level evidence is lacking, numerous retrospective studies have depicted the value of supplemental oxygen in idiopathic pulmonary fibrosis (IPF) and other interstitial lung diseases, and its use should be encouraged where necessary. The clinical course and survival of patients with IPF who have been introduced to oxygen therapy is still not fully understood. The objective of this study was to clarify overall survival, factors associated with prognosis, and causes of death in IPF patients after the start of oxygen therapy. This is a prospective cohort multicenter study, enrolling patients with IPF who started oxygen therapy at 19 hospitals with expertise in interstitial lung disease. Baseline clinical data at the start of oxygen therapy and 3-year follow-up data including death and cause of death were assessed. Factors associated with prognosis were analyzed using univariable and multivariable analyses. One hundred forty-seven eligible patients, of whom 86 (59%) were prescribed ambulatory oxygen therapy and 61 (41%) were prescribed long-term oxygen therapy, were recruited. Of them, 111 died (76%) during a median follow-up of 479 days. The median survival from the start of oxygen therapy was 537 ± 74 days. In the univariable analysis, low body mass index (BMI), low forced vital capacity (FVC), low diffusion capacity (DLCO), resting hypoxemia, short 6 min-walk distance, and high COPD assessment test (CAT) score were significantly associated with poor prognosis. Multivariable analysis revealed low BMI, low FVC, low DLCO, low minimum SpO2 on 6MWT, and high CAT score were independent factors for poor prognosis. The overall survival of IPF patients after starting oxygen therapy is about 1.5 years. In addition to pulmonary function tests, 6MWT and patient reported outcomes can be used to predict prognosis more accurately.Clinical Trial Registration: UMIN000009322.

Fibroblast-derived Extracellular Vesicles Induce Lung Cancer Progression in the Idiopathic Pulmonary Fibrosis Microenvironment

Idiopathic pulmonary fibrosis (IPF) is a progressive aging-related lung disease associated with increased lung cancer risk. Although previous studies have shown that IPF worsens the survival of patients with lung cancer, whether IPF independently affects cancer malignancy and prognosis remains inconclusive. Extracellular vesicles (EVs) have recently emerged as active carriers of molecular biomarkers and mediators of intercellular communication in lung homeostasis and pathogenesis. EV cargo-mediated fibroblast-tumor cell communication might participate in the development and progression of lung cancer by modulating various signaling pathways. In this study, we examined the impact of lung fibroblast (LF)-derived EVs on non-small cell lung cancer (NSCLC) malignancy in the IPF microenvironment. Here, we showed that LFs derived from patients with IPF have phenotypes of myofibroblast differentiation and cellular senescence. Furthermore, we found that IPF LF-derived EVs have markedly altered microRNA compositions and exert proproliferative functions on NSCLC cells. Mechanistically, the phenotype was attributed mainly to the enrichment of miR-19a in IPF LF-derived EVs. As a downstream signaling pathway, mir-19a in IPF LF-derived EVs regulates ZMYND11-mediated c-Myc activation in NSCLC, potentially contributing to the poor prognosis of patients with NSCLC with IPF. Our discoveries provide novel mechanistic insights for understanding lung cancer progression in the IPF microenvironment. Accordingly, blocking the secretion of IPF LF-derived EV miR-19a and their signaling pathways is a potential therapeutic strategy for managing IPF and lung cancer progression.

Can transbronchial lung cryobiopsy benefit adaptive treatment strategies in connective tissue disease-associated interstitial lung disease?

BACKGROUND

Some patients with connective tissue disease (CTD)-associated interstitial lung disease (ILD) progress to pulmonary fibrosis over their disease course despite initial improvement, potentially indicating a poor prognosis. Transbronchial lung cryobiopsy (TBLC) is a new bioptic approach used in diffuse parenchymal lung diseases. This study of CTD-ILD assessed the utility of TBLC in determining therapeutic decision-making strategies.

METHODS

We analyzed medical records of 31 consecutive CTD-ILD patients who underwent TBLC focusing on radio-pathological correlation and disease course. A TBLC-based usual interstitial pneumonia (UIP) score was used that assessed three morphologic descriptors: i) patchy fibrosis, ii) fibroblastic foci, and iii) honeycombing.

RESULTS

Among the patients with CTD-ILD, 3 had rheumatoid arthritis, 2 systemic sclerosis, 5 polymyositis/dermatomyositis, 8 anti-synthetase syndrome, 6 Sjögren's syndrome, and 5 had microscopic polyangiitis. Pulmonary function test results showed a mean %FVC of 82.4% and %DL_CO of 67.7%. Among the 10 CTD patients and TBLC-proven pathological UIP, 3 patients had prominent inflammatory cells in addition to a framework of UIP, and pulmonary function of most patients improved with anti-inflammatory agents. Six (40%) of 15 patients with TBLC-based UIP score ≥ 1 had a progressive disease course during follow-up, of whom 4 patients received anti-fibrotic agents.

CONCLUSIONS

TBLC in patients with CTD-ILD can help determine an appropriate medication strategy, particularly when UIP-like lesions are present. TBLC may be useful when judging which agents to prioritize, anti-inflammatory or anti-fibrotic, is difficult. Moreover, additional information from TBLC may be beneficial when considering early intervention with anti-fibrotic agents in clinical practice.

Drugs against metabolic diseases as potential senotherapeutics for aging-related respiratory diseases

Recent advances in aging research have provided novel insights for the development of senotherapy, which utilizes cellular senescence as a therapeutic target. Cellular senescence is involved in the pathogenesis of various chronic diseases, including metabolic and respiratory diseases. Senotherapy is a potential therapeutic strategy for aging-related pathologies. Senotherapy can be classified into senolytics (induce cell death in senescent cells) and senomorphics (ameliorate the adverse effects of senescent cells represented by the senescence-associated secretory phenotype). Although the precise mechanism has not been elucidated, various drugs against metabolic diseases may function as senotherapeutics, which has piqued the interest of the scientific community. Cellular senescence is involved in the pathogenesis of chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF), which are aging-related respiratory diseases. Large-scale observational studies have reported that several drugs, such as metformin and statins, may ameliorate the progression of COPD and IPF. Recent studies have reported that drugs against metabolic diseases may exert a pharmacological effect on aging-related respiratory diseases that can be different from their original effect on metabolic diseases. However, high non-physiological concentrations are needed to determine the efficacy of these drugs under experimental conditions. Inhalation therapy may increase the local concentration of drugs in the lungs without exerting systemic adverse effects. Thus, the clinical application of drugs against metabolic diseases, especially through an inhalation treatment modality, can be a novel therapeutic approach for aging-related respiratory diseases. This review summarizes and discusses accumulating evidence on the mechanisms of aging, as well as on cellular senescence and senotherapeutics, including drugs against metabolic diseases. We propose a developmental strategy for a senotherapeutic approach for aging-related respiratory diseases with a special focus on COPD and IPF.

COVID-19-Associated Pulmonary Aspergillosis Complicated by Severe Coronavirus Disease: Is Detection of Aspergillus in Airway Specimens Before Disease Onset an Indicator of Antifungal Prophylaxis?

A 55-year-old man was admitted for coronavirus disease 2019 (COVID-19)-related respiratory failure. He was treated with corticosteroids and tocilizumab in the intensive care unit. Aspergillus fumigatus (A. fumigatus) was isolated from his sputum on admission. However, no radiological findings suggesting pulmonary aspergillosis were seen on chest computed tomography (CT). Since the fungus had merely colonized in airways, antifungal drugs were not administered immediately. On day 19 of hospitalization, a high (1→3)-β-D-glucan (BDG) level was noted. A CT scan on day 22 revealed consolidations with a cavity in the right lung. A. fumigatus was isolated from his sputum again. Thus, we diagnosed the patient with COVID-19-associated pulmonary aspergillosis (CAPA) and started voriconazole. After the treatment, BDG levels and radiological findings were noted to improve. In this case, tocilizumab probably had a critical role in developing the disease. Although antifungal prophylaxis therapy for CAPA is not well established, this case shows that detecting Aspergillus in airway specimens before the disease onset possibly implies a high risk of developing CAPA and is an indicator of antifungal prophylaxis.

The usefulness of change in CT score for evaluating the activity of Mycobacterium abscessus (Mab) pulmonary disease (Mab-PD)

OBJECTIVES

Semi-quantitative CT score is generally used for evaluating the disease status of Mycobacterium abscessus (Mab) Pulmonary disease (Mab-PD). However, its accuracy and clinical usefulness are limited, since the CT score is largely affected by coexisting lung disease. Hence, we hypothesized that numerical change in CT score during the observation period may be useful for evaluating disease activity of Mab-PD.

METHODS

Patients diagnosed with Mab-PD based on the official ATS/ERS/ESCMID/IDSA statement at Jikei University Hospital and Jikei Daisan Hospital between 2015 January 1 and 2021 July 31 were included (n = 32). We reviewed the medical records, and bacteriological and laboratory data of the patients. Chest CT was performed at diagnosis in all 32 cases. In 18 cases, chest CT images within 4 years before diagnosis were available. The numerical change in CT score between two time points was calculated and the association of the CT scores with sputum Gaffky score and serum CRP was examined.

RESULTS

CT score at diagnosis was not correlated with sputum Gaffky score nor serum CRP, while the difference of absolute value and change rate in CT score between at diagnosis and immediate past CT were well correlated with both sputum Gaffky score and serum CRP.

CONCLUSIONS

Chronological change in CT score may more precisely reflect the disease activity of airway mycobacterial burden and systemic inflammation in Mab-PD at the timing of diagnosis.

A randomized controlled phase III trial protocol: perioperative pirfenidone therapy in patients with non-small-cell lung cancer combined with idiopathic pulmonary fibrosis to confirm the preventative effect against postoperative acute exacerbation: the PIII-PEOPLE study (NEJ034)

Background

Radical treatment for non-small cell lung cancer (NSCLC) combined with idiopathic pulmonary fibrosis (IPF) is challenging to plan due to the invasiveness of lung cancer and an acute exacerbation (AE) of IPF that is sometimes lethal.

Methods

We intend to conduct the PIII-PEOPLE study (NEJ034), which is a phase III multicenter prospective randomized controlled clinical trial, to validate the effect of perioperative pirfenidone therapy (PPT), involving oral pirfenidone (600 mg) administration for 14 days after registration followed by oral pirfenidone (1,200 mg) for more than 14 days before surgery, with additional oral pirfenidone resumed and continued after surgery. Another group (control) will be allowed to perform any AE preventative treatment, excluding anti-fibrotic agents. Surgery without any preventative measures is also allowed in the control group. The primary endpoint is the IPF exacerbation rate within 30 days postoperatively. The data analysis will be performed in 2023-2024.

Discussion

This trial will validate the perioperative AE suppression effect of PPT, and survival benefits including overall, cancer-free, and IP progression free survival due to PPT. It leads to the establishment of an optimized therapeutic strategy for NSCLC combined with IPF.

Trial Registration

This trial has been registered at the UMIN Clinical Trials Registry as UMIN000029411 (http://www.umin.ac.jp/ctr/).

Minoxidil-induced lung disease, masquerading as hypersensitivity pneumonitis

We report the case of a 71-year-old male with essential thrombosis who presented with ground-glass lung opacity with a mosaic pattern on computed tomography, which resolved spontaneously with hospitalization. This was confused with a case of hypersensitivity pneumonitis (HP), which later turned out to be a drug-induced lung disease caused by surreptitiously administered minoxidil. This case emphasizes the importance of obtaining a correct medication history to make an accurate diagnosis, and this is the first report of minoxidil causing HP-like pulmonary illness.

Long-Term Efficacy and Clinical Remission After Benralizumab Treatment in Patients with Severe Eosinophilic Asthma: A Retrospective Study

BACKGROUND

Few studies on the long-term efficacy of benralizumab, an anti-interleukin-5 receptor α monoclonal antibody, have been conducted for patients with severe eosinophilic asthma (SEA), especially regarding the improvement of pulmonary function and clinical remission in a real-world setting.

OBJECTIVE

To elucidate the long-term efficacy and clinical remission rate (CRR) in patients with SEA.

METHODS

From July 2018 to July 2022, 23 Japanese patients with SEA received benralizumab for two years or more at Jikei University Hospital. We retrospectively evaluated the patients' characteristics, biomarkers, number of exacerbations, pulmonary function, asthma symptoms, maintenance oral corticosteroid (OCS) dose and CRR.

RESULTS

The mean observation period was 38.3 (24-49) months. Among the 23 patients, 10 patients switched from mepolizumab to benralizumab. After administration of benralizumab, the forced expiratory volume in one second (FEV1) increased and was maintained for two years in the biologic-naïve group and in the switching group (177 ± 404 and 151 ± 236 [mL], respectively, P = 0.80). In all patients, the %FEV1 improved from 76.7 ± 22.9% to 84.3 ± 18.4% (P = 0.016), and the number of annual exacerbations decreased from 2.5 ± 3.3 to 0.74 ± 1.7 (P = 0.014). Furthermore, the Asthma Control Test score significantly improved, and the reduction in OCS dose was maintained for three years. Ultimately, five patients met the clinical remission criteria and exhibited stabilization of pulmonary function, no exacerbation, no OCS use and well-controlled symptoms. The CRR was significantly higher in patients with a blood basophil count (BBC) ≥ 22 than in those with a BBC < 22 (/µL) (38.5% vs 0%, respectively, P = 0.046).

CONCLUSION

Long-term treatment with benralizumab significantly improved pulmonary function, alleviated asthma symptoms and decreased the number of exacerbations at two years in a real-world setting. The CRR may be associated with the BBC at baseline.

Frailty and muscle weakness in elderly patients with asthma and their association with cumulative lifetime oral corticosteroid exposure

BACKGROUND

Frailty is a geriatric syndrome of age-related physiological decline, which is associated with higher mortality and decreased healthy life expectancy, and muscle weakness is one of the presentations of frailty. We investigated an association between lifetime oral corticosteroid (OCS) exposure with frailty and muscle weakness among elderly patients with asthma.

METHODS

We studied 203 consecutive elderly outpatients with asthma aged ≥60 years old. They were classified into three groups according to their cumulative lifetime OCS dose (lifetime non-users, lower-dose users, and higher-dose users), which was retrospectively estimated from the response to a structured questionnaire. The prevalence of frailty determined by the Kihon Checklist was compared between the three groups. Hand-grip strength, and lean mass index were also measured as markers of muscle strength.

RESULTS

Thirty-seven percent of the patients studied were considered frail. Higher cumulative lifetime OCS exposure was associated with a significantly higher prevalence of frailty (33% in lifetime non-users, 59% in lower-dose users, and 68% in higher-dose users; P for trend <0.005). This was also associated with lower hand-grip strength in both sexes (P for trend; 0.012 in men, and 0.020 in women), and lower lean mass index in men (P for trend 0.002). However, current doses of OCS were not significantly associated with these outcomes.

CONCLUSIONS

Cumulative lifetime OCS exposure was associated with a higher prevalence of frailty and muscle weakness. These findings emphasize the importance of minimizing lifetime OCS exposure for the prolongation of healthy life expectancy in patients with asthma.

Liquid biopsy for the detection of resistance mutations to ROS1 and RET inhibitors in non-small lung cancers: A case series study

Liquid biopsy can identify gene alterations that are associated with resistance to fusion gene-targeted treatments. In this study, we present three cases of advanced non-small cell lung cancer (NSCLC) harboring gene fusions; cell-free DNA (cfDNA) was used to assess the resistance mutations. A patient with MET amplification underwent RET-fusion NSCLC treatment with selpercatinib. A patient with ROS1 G2032R underwent ROS1-fusion NSCLC treatment with crizotinib. A patient who underwent ROS1-fusion NSCLC treatment with crizotinib harbored no somatic mutations. This case series shows that cfDNA analysis can identify potentially actionable genomic alterations, after disease progression, in targeted therapy for fusion genes. TRIAL REGISTRATION: The study was registered in the UMIN Clinical Trial Registry (UMIN 000017581).

Patient background and prognosis of chronic pulmonary aspergillosis in fibrosing interstitial lung disease

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

Necessity of neutrophil-to-lymphocyte ratio monitoring for hypothyroidism using nivolumab in patients with cancer

BACKGROUND

Low neutrophil-to-lymphocyte ratio (NLR) has been shown to be associated with a favorable therapeutic response to nivolumab. The activation of immunocompetent cells such as lymphocytes exhibits an antitumor effect; however, the development of excessive immune responses in autologous organs along with the breakdown of self-tolerance causes immune-related adverse events, including hypothyroidism. Therefore, the possibility that NLR is associated with immune response shows that NLR can be not only a predictive factor for good response to nivolumab but also a predictive factor for the development of hypothyroidism.

AIM

To evaluate whether continuous NLR monitoring during nivolumab treatment is useful for predicting the incidence and onset period of hypothyroidism.

METHODS

This retrospective study comprised patients who received nivolumab for treating all types of cancer at our hospital between January 2015 and December 2019. The NLRs of patients were measured before each administration, and the patients were followed up till the administration of 12 doses. NLR at treatment initiation was compared between patients with and without hypothyroidism. Patients who developed hypothyroidism were categorized into three groups: those with NLR < 3.5, 3.5 to < 5, and ≥ 5 according to their maximum NLR from treatment initiation to hypothyroidism development. Further, the onset periods of hypothyroidism were compared between the groups.

RESULTS

Overall, 104 patients were included in the analysis. Twenty-one patients developed hypothyroidism throughout the observation period. NLR at treatment initiation was significantly lower (2.54 ± 1.21 vs 4.58 ± 4.03; P = 0.017) in patients with hypothyroidism than in those without hypothyroidism, and patients with NLR < 5 had a significantly higher incidence of hypothyroidism than those with NLR ≥ 5 (26%: 20 of 78 patients vs 4%: 1 of 26 patients; P = 0.022). Additionally, treatment continuity in patients with hypothyroidism was significantly longer than in those without hypothyroidism (median not reached vs 7 times administration, P = 0.010). Patients with maximum NLR < 3.5 until the development of hypothyroidism had a significantly earlier onset of hypothyroidism than those with maximum NLR ≥ 5 (hazard ratio for low tertile [NLR < 3.5] vs high tertile [NLR ≥ 5]: 5.33, P = 0.011).

CONCLUSION

Low NLR at treatment initiation increases the incidence of treatment-induced hypothyroidism. Furthermore, its persistence may be a risk factor for the early onset of hypothyroidism.

Clinical features of organizing pneumonia in anti-aquaporin-4 antibody-positive neuromyelitis optica spectrum disorders

BACKGROUND

Anti-aquaporin-4 (AQP4) antibody is an autoantibody marker often observed in patients with neuromyelitis optica spectrum disorder (NMOSD). The pathological relevance of complicated pulmonary disorders in anti-AQP4 antibody-positive NMOSD remains unclear. We aimed to assess the clinical and histological relevance of complicated pulmonary disorders in anti-AQP4 antibody-positive NMOSD.

METHODS

We retrospectively reviewed the medical records of 52 patients with anti-AQP4 antibody-positive NMOSD and conducted immunohistochemical evaluations of the lung biopsy specimens.

RESULTS

Among 52 patients with anti-AQP4 antibody-positive NMOSD, 4 patients showed pulmonary involvement with a diagnosis of organizing pneumonia (OP). The proportion of males was larger (75% vs. 12.5%; p = 0.013) and creatine kinase levels were higher (458.3 U/L vs. 83.9 U/L; p = 0.003) in patients with OP than in those without OP. OP development preceded or coincided with the NMOSD symptoms. Chest computed tomography findings were consistent with OP in all four patients. Bronchoalveolar lavage fluid predominantly contained lymphocytes. Transbronchial lung biopsy revealed intraluminal plugs of inflammatory debris within the alveoli. Alveolar epithelial cells covering the OP lesions exhibited AQP4 loss, immunoglobulin G deposition, and complement activation. Corticosteroid treatment resulted in clinical improvement of OP.

CONCLUSION

OP may be considered a pulmonary manifestation of anti-AQP4 antibody-positive NMOSD beyond the central nervous system. Complement-dependent cytotoxicity of the lung epithelial cells caused by anti-AQP4 antibody is at least partly involved in OP development. When diagnosing NMOSD, the possibility of OP should be carefully evaluated based on the detailed history and chest imaging findings.

A Convenient Risk Prediction Score for COVID-19 for Determining Whether or Not Hospitalization Is Recommended: Kanagawa Admission Priority Assessment Score

Objective Coronavirus disease 2019 (COVID-19) has caused a collapse of the medical care system, with effective triage proving vital. The Kanagawa admission priority assessment score, version-1 (KAPAS-1) and version-2 (KAPAS-2), was developed to determine the need for hospitalization. Patients with a high KAPAS (≥5) are recommended for hospitalization. We retrospectively investigated the correlation between the KAPAS and oxygen requirement during hospitalization. Methods We collected the clinical data of COVID-19 patients admitted between February 5 and December 6, 2020. Patients were divided into two groups: those who required oxygen therapy during hospitalization (OXY) and those who did not (NOXY). We assessed the correlations between the groups and KAPAS-1 and KAPAS-2. Results Overall, 117 COVID-19 patients were analyzed, including 20 OXY and 97 NOXY and 54 high KAPAS-1 and 63 high KAPAS-2. The median KAPAS-1 and KAPAS-2 were significantly higher in OXY than in NOXY (6.5 vs. 3, and 9 vs. 4, respectively). The areas under the receiver operating characteristic curves of KAPAS-1 and KAPAS-2 for oxygen requirement were 0.777 and 0.825, respectively, and the maximum values of Youden's index were 4 and 6, respectively. The proportions of high KAPAS-1 and high KAPAS-2 were significantly higher in OXY than in NOXY (90.0% vs. 37.1%, and 90.0% vs. 46.4%, respectively). Conclusion The KAPAS was significantly correlated with oxygen requirement. Furthermore, the KAPAS may be useful for deciding which patients are most likely to require hospitalization and for selecting non-hospitalized patients who should be carefully monitored.

Real-life effectiveness of dupilumab in patients with mild to moderate bronchial asthma comorbid with CRSwNP

BACKGROUND

Dupilumab, an anti-IL-4α receptor antibody, is a new treatment for severe or refractory asthma. However, real-world evidence on the efficacy of dupilumab in patients with mild to moderate bronchial asthma is lacking.

METHODS

We retrospectively evaluated the effects of dupilumab in 62 patients who received dupilumab for eosinophilic sinusitis comorbid with asthma at a single centre in Japan. Type 2 inflammatory markers, ACT, respiratory function tests, and forced oscillation technique (FOT) were analysed before, three months after, and one year after dupilumab administration, mainly in patients with mild to moderate asthma.

RESULTS

FEV1, %FEV1, %FVC, treatment steps for asthma and ACT improved significantly after three months of dupilumab treatment. FeNO was markedly decreased, whereas IgE and eosinophil counts showed no significant changes. Pre- and post-treatment respiratory resistance (Rrs) and respiratory reactance (Xrs) correlated significantly with FEV1. Improvement in %FEV1 was associated with higher FeNO and higher serum IgE before dupilumab treatment.

CONCLUSION

Dupilumab treatment for sinusitis may improve respiratory functions, asthma symptoms, and asthma treatment reduction, even if the associated bronchial asthma is not severe.

Aspiration of Cerebrospinal Fluid Rhinorrhea as a Cause of Non-resolving Pneumonia

We herein report two cases of cerebrospinal fluid (CSF) rhinorrhea associated with lung infiltrates. One patient presented with symptomatic non-resolving pneumonia, while the other was asymptomatic. In both cases, the lung infiltrates completely resolved when CSF leakage had subsided. Pulmonary involvement in CSF rhinorrhea is under-recognized, and despite being the definitive treatment, surgery for CSF rhinorrhea is typically postponed due to the presence of lung infiltrates. However, meningitis is a serious complication due to a delay in surgical management. Physicians should be made aware that CSF rhinorrhea is a potential cause of intractable lung infiltrates.

Involvement of Parkin-mediated mitophagy in the pathogenesis of chronic obstructive pulmonary disease-related sarcopenia

BACKGROUND

Sarcopenia is characterized by the loss of skeletal muscle mass and strength and is associated with poor prognosis in patients with chronic obstructive pulmonary disease (COPD). Cigarette smoke (CS) exposure, a major cause for COPD, induces mitochondrial damage, which has been implicated in sarcopenia pathogenesis. The current study sought to examine the involvement of insufficient Parkin-mediated mitophagy, a mitochondrion-selective autophagy, in the mechanisms by which dysfunctional mitochondria accumulate with excessive reactive oxygen species (ROS) production in the development of COPD-related sarcopenia.

METHODS

The involvement of Parkin-mediated mitophagy was examined using in vitro models of myotube formation, in vivo CS-exposure model using Parkin^-/- mice, and human muscle samples from patients with COPD-related sarcopenia.

RESULTS

Cigarette smoke extract (CSE) induced myotube atrophy with concomitant 30% reduction in Parkin expression levels (P < 0.05). Parkin-mediated mitophagy regulated myotube atrophy by modulating mitochondrial damage and mitochondrial ROS production. Increased mitochondrial ROS was responsible for myotube atrophy by activating Muscle Ring Finger 1 (MuRF-1)-mediated myosin heavy chain (MHC) degradation. Parkin^-/- mice with prolonged CS exposure showed enhanced limb muscle atrophy with a 31.7% reduction in limb muscle weights (P < 0.01) and 2.3 times greater MuRF-1 expression (P < 0.01) compared with wild-type mice with concomitant accumulation of damaged mitochondria and oxidative modifications in 4HNE expression. Patients with COPD-related sarcopenia exhibited significantly reduced Parkin but increased MuRF-1 protein levels (35% lower and 2.5 times greater protein levels compared with control patients, P < 0.01 and P < 0.05, respectively) and damaged mitochondria accumulation demonstrated in muscles. Electric pulse stimulation-induced muscle contraction prevented CSE-induced MHC reduction by maintaining Parkin levels in myotubes.

CONCLUSIONS

Taken together, COPD-related sarcopenia can be attributed to insufficient Parkin-mediated mitophagy and increased mitochondrial ROS causing enhanced muscle atrophy through MuRF-1 activation, which may be at least partly preventable through optimal physical exercise.

Extracellular vesicle-mediated cellular crosstalk in lung repair, remodelling and regeneration

The unperturbed lung is highly quiescent, with a remarkably low level of cell turnover. However, once damaged, the lung shows an extensive regenerative capacity, with resident progenitor cell populations re-entering the cell cycle and differentiating to promote repair. This quick and dramatic repair response requires interactions among more than 40 different cell lineages in the lung, and defects in any of these processes can lead to various lung pathologies. Understanding the mechanisms of interaction in lung injury, repair and regeneration thus has considerable practical and therapeutic implications. Moreover, therapeutic strategies for replacing lung progenitor cells and their progeny through cell therapy have gained increasing attention. In the last decade, extracellular vesicles (EVs), including exosomes, have been recognised as paracrine mediators through the transfer of biological cargo. Recent work has revealed that EVs are involved in lung homeostasis and diseases. In addition, EVs derived from specific cells or tissues have proven to be a promising cell-free modality for the treatment of lung diseases. This review highlights the EV-mediated cellular crosstalk that regulates lung homeostasis and discusses the potential of EV therapeutics for lung regenerative medicine.

Possible relationship between esophageal dilatation and severity of M. abscessus pulmonary disease

Objectives

Recently, incidence of Mycobacterium abscessus (Mab) pulmonary disease (Mab-PD) is increasing worldwide. We aimed to identify factors associated with severity of Mycobacterium abscessus (Mab) pulmonary disease (Mab-PD).

Methods

All patients diagnosed as Mab-PD based on the official ATS/IDSA statement between 2017 January 1 and 2021 July 31 were included (n = 13). We reviewed medical records, bacteriological and laboratory data of the patients. Severity of lung lesions and esophageal diameters in chest CT were quantitatively evaluated. Gaffky score in the sputum was used as airway mycobacterial burden. We explored the factors associated with high CT score and high Gaffky score.

Results

Maximum diameter of esophagus (MDE) in severe disease (CT score≧10) was greater than that in milder disease (CT score<10) (18.0±7.9mm, 9.3±3.1mm, respectively, p = 0.01), and MDE was well correlated with CT score (R = 0.69, p = 0.007). MDE in high mycobacterial burden group (Gaffky score ≧5) tended to be greater than that in low mycobacterial burden group (Gaffky score <5) (16.1±6.8mm, 10.1±5.5mm, respectively, p = 0.12), and MDE was well correlated with Gaffky score (R = 0.68, p = 0.009). Lung lesions were bilateral and predominant in middle or lower lobes.

Conclusions

Esophageal dilatation was correlated with severity of Mab-PD and airway mycobacterial burden. Gastroesophageal reflux might be associated with Mab disease progression.

Prognostic value of radiological findings indeterminate for UIP pattern and anterior upper lobe honeycomb-like lesion in chronic fibrosing interstitial lung disease associated with MPO-ANCA

Background

Myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) is often positive in patients with interstitial lung disease (ILD), which is also often present in patients with microscopic polyangiitis (MPA). A possible association between MPO-ANCA, MPA, and idiopathic ILD remains unclear. The objective of this study was to determine whether high-resolution computed tomography (HRCT) classification based on recent idiopathic pulmonary fibrosis guideline and specific CT findings can obtain new knowledge of prognostic factors in all MPO-ANCA-positive patients with ILD including both idiopathic ILD and MPA-ILD.

Methods

We analyzed 101 consecutive MPO-ANCA-positive patients with respiratory disease. We assessed the diagnostic accuracy of CT findings, HRCT pattern, and specific radiological signs. Prognostic predictors were determined using Cox regression models.

Results

Subjects with chronic ILD included 22 patients with MPA-ILD and 39 patients with ILD but without MPA. A quarter of the patients were radiological indeterminate for usual interstitial pneumonia (UIP) pattern, which resulted in a better prognosis than that for UIP pattern. “Increased attenuation around honeycomb and traction bronchiectasis” and “anterior upper lobe honeycomb-like lesion” were found to be highly frequent radiological findings (39% and 30%, respectively). In addition, the latter finding was a significant negative prognostic factor.

Conclusions

Radiological indeterminate for UIP was a useful HRCT classification in MPO-ANCA-positive patients with ILD. In addition, anterior upper lobe honeycomb-like lesion was found to be specific radiological finding that was a significant prognostic factor. The present results might aid in the assessment of appropriate strategies of diagnosis in these patients.

Role of chaperone-mediated autophagy in the pathophysiology including pulmonary disorders

Autophagy is a highly conserved mechanism of delivering cytoplasmic components for lysosomal degradation. Among the three major autophagic pathways, chaperone-mediated autophagy (CMA) is primarily characterized by its selective nature of protein degradation, which is mediated by heat shock cognate 71 kDa protein (HSC70: also known as HSPA8) recognition of the KFERQ peptide motif in target proteins. Lysosome-associated membrane protein type 2A (LAMP2A) is responsible for substrate binding and internalization to lysosomes, and thus, the lysosomal expression level of LAMP2A is a rate-limiting factor for CMA. Recent advances have uncovered not only physiological but also pathological role of CMA in multiple organs, including neurodegenerative disorders, kidney diseases, liver diseases, heart diseases, and cancers through the accumulation of unwanted proteins or increased degradation of target proteins with concomitant metabolic alterations resulting from CMA malfunction. With respect to pulmonary disorders, the involvement of CMA has been demonstrated in lung cancer and chronic obstructive pulmonary disease (COPD) pathogenesis through regulating apoptosis. Further understanding of CMA machinery may shed light on the molecular mechanisms of refractory disorders and lead to novel treatment modalities through CMA modulation.

Solitary pulmonary nodule caused by pulmonary Mycobacterium lentiflavum infection

An 82-year-old Japanese man who previously had descending colon cancer and underwent partial resection showed a growing solitary pulmonary nodule, suspected as lung cancer, on follow-up computed tomography. Thoracoscopic partial lobectomy was therefore performed. The surgical specimen showed granulomatous lesions with necrosis. Mass spectrometry was performed on the sputum specimen collected after surgery, which identified Mycobacterium lentiflavum infection. Antibiotics were not prescribed following surgery, and the patient has not experienced recurrence 2 years since the surgery. To our knowledge, this is the second case of solitary pulmonary nodule and the first case of M. lentiflavum infection treated via surgical resection.

Iliopsoas gravity abscess secondary to a tuberculous empyema

A 29-year-old Japanese man with a history of right-sided tuberculous pleurisy presented with fever and right flank pain. Computed tomography images revealed a right pleural effusion and an area of low attenuation in the right iliopsoas muscle. Percutaneous drainage of the iliopsoas lesion resulted in a bloody pyogenic discharge that tested positive for Mycobacterium tuberculosis by both acid-fast staining and polymerase chain reaction. Enhanced fluoroscopy revealed a perforation of the diaphragm between the thoracic region and the psoas muscle. The patient was diagnosed with an iliopsoas abscess secondary to tuberculous empyema.

Allergic bronchopulmonary aspergillosis in a patient with ankylosing spondylitis treated with adalimumab

We herein report a case of allergic bronchopulmonary aspergillosis (ABPA) that occurred in a man treated with adalimumab for ankylosing spondylitis (AS). A 69-year-old man with a history of ankylosing spondylitis treated by adalimumab, an anti-tumour necrosis factor-α (TNF-α) antibody, developed cough and wheezing. Chest computed tomography showed obstruction of dilated left upper lobe bronchus by high attenuation mucus as well as central bronchiectasis. Both Aspergillus-specific immunoglobulin E (IgE) and Aspergillus precipitating antibody were positive and Aspergillus fumigatus was detected in a sputum culture. According to the new diagnostic criteria, the patient was diagnosed with ABPA. His condition rapidly improved after the withdrawal of adalimumab and initiation of prednisolone and itraconazole. Anti-TNF-α antibody might cause ABPA through both aggravation of the host's T-helper 2 immunological response and anti-fungal response.

Human bronchial epithelial cell-derived extracellular vesicle therapy for pulmonary fibrosis via inhibition of TGF-β-WNT crosstalk

Idiopathic pulmonary fibrosis (IPF) is characterized by devastating and progressive lung parenchymal fibrosis, resulting in poor patient prognosis. An aberrant recapitulation of developmental lung gene expression, including genes for transforming growth factor (TGF)-β and WNT, has been widely implicated in the pathogenic IPF wound healing process that results from repetitive alveolar epithelial injury. Extracellular vesicles (EVs) have been shown to carry bioactive molecules and to be involved in various physiological and pathological processes. Here, we demonstrate that, by attenuating WNT signalling, human bronchial epithelial cell-derived EVs (HBEC EVs) inhibit TGF-β mediated induction of both myofibroblast differentiation and lung epithelial cellular senescence. This effect of HBEC EVs is more pronounced than that observed with mesenchymal stem cell-derived EVs. Mechanistically, the HBEC EV microRNA (miRNA) cargo is primarily responsible for attenuating both myofibroblast differentiation and cellular senescence. This attenuation occurs via inhibition of canonical and non-canonical WNT signalling pathways. Among enriched miRNA species present in HBEC EVs, miR-16, miR-26a, miR-26b, miR-141, miR-148a, and miR-200a are mechanistically involved in reducing WNT5A and WNT10B expression in LFs, and in reducing WNT3A, WNT5A, and WNT10B expression in HBECs. Mouse models utilizing intratracheal administration of EVs demonstrate efficient attenuation of bleomycin-induced lung fibrosis development accompanied by reduced expression of both β-catenin and markers of cellular senescence. These findings indicate that EVs derived from normal resident lung HBECs may possess anti-fibrotic properties. They further suggest that, via miRNA-mediated inhibition of TGF-β-WNT crosstalk, HBEC EVs administration can be a promising anti-fibrotic modality of treatment for IPF.

Impaired TRIM16-Mediated Lysophagy in Chronic Obstructive Pulmonary Disease Pathogenesis

Insufficient autophagic degradation has been implicated in accelerated cellular senescence during chronic obstructive pulmonary disease (COPD) pathogenesis. Aging-linked and cigarette smoke (CS)-induced functional deterioration of lysosomes may be associated with impaired autophagy. Lysosomal membrane permeabilization (LMP) is indicative of damaged lysosomes. Galectin-3 and tripartite motif protein (TRIM) 16 play a cooperative role in recognizing LMP and inducing lysophagy, a lysosome-selective autophagy, to maintain lysosome function. In this study, we sought to examine the role of TRIM16-mediated lysophagy in regulating CS-induced LMP and cellular senescence during COPD pathogenesis by using human bronchial epithelial cells and lung tissues. CS extract (CSE) induced lysosomal damage via LMP, as detected by galectin-3 accumulation. Autophagy was responsible for modulating LMP and lysosome function during CSE exposure. TRIM16 was involved in CSE-induced lysophagy, with impaired lysophagy associated with lysosomal dysfunction and accelerated cellular senescence. Airway epithelial cells in COPD lungs showed an increase in lipofuscin, aggresome and galectin-3 puncta, reflecting accumulation of lysosomal damage with concomitantly reduced TRIM16 expression levels. Human bronchial epithelial cells isolated from COPD patients showed reduced TRIM16 but increased galectin-3, and a negative correlation between TRIM16 and galectin-3 protein levels was demonstrated. Damaged lysosomes with LMP are accumulated in epithelial cells in COPD lungs, which can be at least partly attributed to impaired TRIM16-mediated lysophagy. Increased LMP in lung epithelial cells may be responsible for COPD pathogenesis through the enhancement of cellular senescence.

Effectiveness of Switching Biologics for Severe Asthma Patients in Japan: A Single-Center Retrospective Study

BACKGROUND

In Japan, biologic therapy was initiated for patients with severe asthma in 2009. In recent years, four biologics with different mechanisms of action have become available in the clinical setting. However, the efficacy of switching between biologics remains uncertain.

METHODS

To elucidate the efficacy of switching between biologics, 97 patients were enrolled who had received any biologic therapy for severe asthma at Jikei University Hospital, Tokyo, Japan, from July 2009 to December 2020. We retrospectively examined the patient characteristics, biomarkers, pulmonary function test results, selected biologics, and efficacy.

RESULTS

Thirty-one males and 66 females received any biologics. The mean age was 53.3 years at the initiation of biologic therapy. Initially, 33, 41, 15 and eight patients received omalizumab, mepolizumab, benralizumab, and dupilumab, respectively. Among three representative indicators for biologics administration, the peripheral blood eosinophil count, serum IgE levels and fractional exhaled nitric oxide, 64% of the patients had two indicators, and 28% had three indicators. Thirty-four patients (35%) switched from the initial biologic to another, and the reasons for switching included persistent asthmatic symptoms (n=22), schedule of hospital visits (n=5), and other reasons. Thus, the treatment was effective in 11 patients after switching. In addition, two patients received combination therapy with different biologics. Eighteen patients (19%) interrupted treatment for various reasons. Regardless of whether the biologic was the initial therapy, the overall efficacy of the four biologics was 60% based on the global evaluation of treatment effectiveness.

CONCLUSION

Switching between biologics can be a promising option for severe asthma patients in whom treatment with an initial biologic is ineffective.

Early prediction of COVID-19 severity using extracellular vesicle COPB2

The clinical manifestations of COVID-19 vary broadly, ranging from asymptomatic infection to acute respiratory failure and death. But the predictive biomarkers for characterizing the variability are still lacking. Since emerging evidence indicates that extracellular vesicles (EVs) and extracellular RNAs (exRNAs) are functionally involved in a number of pathological processes, we hypothesize that these extracellular components may be key determinants and/or predictors of COVID-19 severity. To test our hypothesis, we collected serum samples from 31 patients with mild COVID-19 symptoms at the time of their admission for discovery cohort. After symptomatic treatment without corticosteroids, 9 of the 31 patients developed severe/critical COVID-19 symptoms. We analyzed EV protein and exRNA profiles to look for correlations between these profiles and COVID-19 severity. Strikingly, we identified three distinct groups of markers (antiviral response-related EV proteins, coagulation-related markers, and liver damage-related exRNAs) with the potential to serve as early predictive biomarkers for COVID-19 severity. As the best predictive marker, EV COPB2 protein, a subunit of the Golgi coatomer complex, exhibited significantly higher abundance in patients remained mild than developed severe/critical COVID-19 and healthy controls in discovery cohort (AUC 1.00 (95% CI: 1.00-1.00)). The validation set included 40 COVID-19 patients and 39 healthy controls, and showed exactly the same trend between the three groups with excellent predictive value (AUC 0.85 (95% CI: 0.73-0.97)). These findings highlight the potential of EV COPB2 expression for patient stratification and for making early clinical decisions about strategies for COVID-19 therapy.

MelLec Exacerbates the Pathogenesis of Aspergillus fumigatus-Induced Allergic Inflammation in Mice

Environmental factors, particularly fungi, influence the pathogenesis of allergic airway inflammation, but the mechanisms underlying these effects are still unclear. Melanin is one fungal component which is thought to modulate pulmonary inflammation. We recently identified a novel C-type lectin receptor, MelLec (Clec1a), which recognizes fungal 1,8-dihydroxynaphthalene (DHN)-melanin and is able to regulate inflammatory responses. Here we show that MelLec promotes pulmonary allergic inflammation and drives the development of Th17 T-cells in response to spores of Aspergillus fumigatus. Unexpectedly, we found that MelLec deficiency was protective, with MelLec^-/- animals showing normal weight gain and significantly reduced pulmonary inflammation in our allergic model. The lungs of treated MelLec^-/- mice displayed significantly reduced inflammatory foci and reduced bronchial wall thickening, which correlated with a reduced cellular influx (particularly neutrophils and inflammatory monocytes) and levels of inflammatory cytokines and chemokines. Notably, fungal burdens were increased in MelLec^-/- animals, without apparent adverse effects, and there were no alterations in the survival of these mice. Characterization of the pulmonary T-cell populations, revealed a significant reduction in Th17 cells, and no alterations in Th2, Th1 or Treg cells. Thus, our data reveal that while MelLec is required to control pulmonary fungal burden, the inflammatory responses mediated by this receptor negatively impact the animal welfare in this allergic model.

The Usefulness of a Transbronchial Lung Cryobiopsy for Diffuse Bronchiolitis

We herein report four cases of diffuse bronchiolitis proven by a transbronchial lung cryobiopsy (TBLC). Based on various aspects, including the pathological findings, we definitively diagnosed two patients with diffuse panbronchiolitis (DPB) and the other two with primary ciliary dyskinesia (PCD). One of the DPB patients had more severe peribronchiolar fibrosis than the other, and the disease course was refractory to macrolide therapy. One of the PCD patients was additionally diagnosed with combined constrictive bronchiolitis. This report highlights the importance of a TBLC in the differentiation of bronchiolitis, suggesting its utility for helping pulmonologists formulate a treatment strategy.

Effect of anti-interleukin-17 biologics on Krebs von den Lungen-6 level in patients with psoriasis

Interleukin (IL)-17 plays critical roles in the pathogenesis of both psoriasis and interstitial pneumonia (IP). We hypothesized that anti-IL-17 biologics might suppress both clinically relevant and latent IP activity and decrease Krebs von den Lungen-6 (KL-6) level in psoriasis patients. We aimed to elucidate the effects of anti-IL-17 biologics on KL-6 levels. We retrospectively analyzed the clinical data of psoriasis patients treated with anti-IL-17 biologics. KL-6 levels were measured before treatment (baseline) and at 3 and 6 months after the initiation of the treatment, and ratios of KL-6 levels at each time point to the baseline levels were calculated. Chest computed tomography (CT) was performed on patients with coexisting IP. The clinical characteristics and radiographic findings were evaluated. A total of 294 psoriasis patients were treated with anti-IL-17 biologics. Baseline KL-6 levels were higher than 401 U/mL in 34 patients (high baseline KL-6 group). While anti-IL-17 biologics did not affect KL-6 levels and ratios of KL-6 to the baseline levels at any time point in the overall study population, they decreased both KL-6 levels and ratios at 6 months after the initiation of the treatment in the high baseline KL-6 group. A total of 10 patients with coexisting IP showed decreasing ratios of KL-6 to the baseline levels at 6 months without affecting coexisting IP in CT performed at 3-12 months. Anti-IL-17 biologics decreased KL-6 levels in the high baseline KL-6 group regardless of recognizable IP. A decrease in KL-6 levels was not associated with a radiographic improvement of IP, which should be examined in large numbers with long-term observations in future studies.

Radiographic features and poor prognostic factors of interstitial lung disease with nivolumab for non-small cell lung cancer

Nivolumab can cause interstitial lung disease (ILD), which may be fatal; however, mortality risk factors have not been identified. This postmarketing study evaluated the poor prognostic factors of ILD in nivolumab-treated patients with non-small cell lung cancer (NSCLC) in Japan. Clinical and chest imaging findings for each ILD case were assessed by an expert central review committee, and prognosis was evaluated by radiographic findings, including the presence/absence of peritumoral ground-glass opacity (peritumoral-GGO). Poor prognostic factors were identified by univariate and multivariate Cox regression analysis. Of the 238 patients with nivolumab-induced ILD, 37 died. The main radiographic patterns of ILD were cryptogenic organizing pneumonia/chronic eosinophilic pneumonia-like (53.4%), faint infiltration pattern/acute hypersensitivity pneumonia-like (20.2%), diffuse alveolar damage (DAD)-like (10.9%), and nonspecific interstitial pneumonia-like (6.3%). The main poor prognostic factors identified were DAD-like pattern (highest hazard ratio: 10.72), ≤60 days from the start of nivolumab treatment to the onset of ILD, pleural effusion before treatment, lesion distribution contralateral or bilateral to the tumor, and abnormal change in C-reactive protein (CRP) levels. Of the 37 deaths due to ILD, 17 had DAD-like radiographic pattern, three had peritumoral-GGO, and five had a change in radiographic pattern from non-DAD at the onset to DAD-like. Patients with NSCLC who develop ILD during nivolumab treatment should be managed carefully if they have poor prognostic factors such as DAD-like radiographic pattern, onset of ILD ≤60 days from nivolumab initiation, pleural effusion before nivolumab treatment, lesion distribution contralateral or bilateral to the tumor, and abnormal changes in CRP levels.

Localized pleural metastasis without other organ metastases after nephrectomy for renal cell carcinoma

We present a case of a 69-year-old man who had localized pleural metastasis without other organ metastases after nephrectomy for right renal cell carcinoma (RCC). He complained of respiratory symptoms for more than two years after the operation and was confirmed to have right pleural effusion and multiple pleural masses on computed tomography (CT). There were no abnormal findings in the other organs, but the pleural mass gradually increased in size on CT. We suspected malignant tumors such as malignant pleural mesothelioma and synovial sarcoma in addition to RCC metastasis. Finally, we performed surgical resection of the pleural mass under general anesthesia, and we diagnosed pathologically as metastasis from RCC. Distant metastases of RCC are common in the lungs, bones, brain, and liver. To our knowledge, localized pleural metastases from RCC is rare.

Treatment and relapse of interstitial lung disease in nivolumab-treated patients with non-small cell lung cancer

Nivolumab, a human monoclonal antibody against programmed death‐1, is approved for the treatment of non–small cell lung cancer (NSCLC). Although nivolumab is generally well tolerated, it can cause interstitial lung disease (ILD), a rare but potentially fatal immune‐related adverse event. Currently, there are limited data available on the treatment of nivolumab‐induced ILD and its outcome. This retrospective cohort study based on a post–marketing study described the treatment of nivolumab‐induced ILD and its outcome in NSCLC patients in Japan through the assessment of clinical and chest imaging findings by an expert central review committee. Treatment details for patients who experienced a relapse of ILD were also analyzed. Of the 238 patients identified as having nivolumab‐induced ILD, 37 patients died of ILD. Corticosteroids were used in 207 (87.0%) patients. Of those, 172 (83.1%) patients responded well and survived and 35 (16.9%) died (most died during corticosteroid treatment). A total of nine patients experienced a relapse; at the time of relapse, four patients were taking nivolumab. Of those who were receiving corticosteroids at the time of relapse, three of four patients were taking low doses or had nearly completed dose tapering. All patients (except one, whose treatment was unknown) received corticosteroids for the treatment of relapse, but one patient died. Patients with NSCLC who experience nivolumab‐induced ILD are treated effectively with corticosteroids, and providing extra care when ceasing or reducing the corticosteroid dose may prevent relapse of ILD.

Intercellular Communication by Vascular Endothelial Cell-Derived Extracellular Vesicles and Their MicroRNAs in Respiratory Diseases

Respiratory diseases and their comorbidities, such as cardiovascular disease and muscle atrophy, have been increasing in the world. Extracellular vesicles (EVs), which include exosomes and microvesicles, are released from almost all cell types and play crucial roles in intercellular communication, both in the regulation of homeostasis and the pathogenesis of various diseases. Exosomes are of endosomal origin and range in size from 50 to 150 nm in diameter, while microvesicles are generated by the direct outward budding of the plasma membrane in size ranges of 100-2,000 nm in diameter. EVs can contain various proteins, metabolites, and nucleic acids, such as mRNA, non-coding RNA species, and DNA fragments. In addition, these nucleic acids in EVs can be functional in recipient cells through EV cargo. The endothelium is a distributed organ of considerable biological importance, and disrupted endothelial function is involved in the pathogenesis of respiratory diseases such as chronic obstructive pulmonary disease, pulmonary hypertension, and acute respiratory distress syndrome. Endothelial cell-derived EVs (EC-EVs) play crucial roles in both physiological and pathological conditions by traveling to distant sites through systemic circulation. This review summarizes the pathological roles of vascular microRNAs contained in EC-EVs in respiratory diseases, mainly focusing on chronic obstructive pulmonary disease, pulmonary hypertension, and acute respiratory distress syndrome. Furthermore, this review discusses the potential clinical usefulness of EC-EVs as therapeutic agents in respiratory diseases.