Increased Oxidative Stress and Decreased Citrulline in Blood Associated with Severe Novel Coronavirus Pneumonia in Adult Patients.

This study investigated the correlation between oxidative stress and blood amino acids associated with nitric oxide metabolism in adult patients with coronavirus disease (COVID-19) pneumonia. Clinical data and serum samples were prospectively collected from 100 adult patients hospitalized for COVID-19 between July 2020 and August 2021. Patients with COVID-19 were categorized into three groups for analysis based on lung infiltrates, oxygen inhalation upon admission, and the initiation of oxygen therapy after admission. Blood data, oxidative stress-related biomarkers, and serum amino acid levels upon admission were compared in these groups. Patients with lung infiltrations requiring oxygen therapy upon admission or starting oxygen post-admission exhibited higher serum levels of hydroperoxides and lower levels of citrulline compared to the control group. No remarkable differences were observed in nitrite/nitrate, asymmetric dimethylarginine, and arginine levels. Serum citrulline levels correlated significantly with serum lactate dehydrogenase and C-reactive protein levels. A significant negative correlation was found between serum levels of citrulline and hydroperoxides. Levels of hydroperoxides decreased, and citrulline levels increased during the recovery period compared to admission. Patients with COVID-19 with extensive pneumonia or poor oxygenation showed increased oxidative stress and reduced citrulline levels in the blood compared to those with fewer pulmonary complications. These findings suggest that combined oxidative stress and abnormal citrulline metabolism may play a role in the pathogenesis of COVID-19 pneumonia.

Identification of exhaled volatile organic compounds that characterize asthma phenotypes: A J-VOCSA study.

BACKGROUND: Asthma is characterized by phenotypes of different clinical, demographic, and pathological characteristics. Identifying the profile of exhaled volatile organic compounds (VOCs) in asthma phenotypes may facilitate establishing biomarkers and understanding asthma background pathogenesis. This study aimed to identify exhaled VOCs that characterize severe asthma phenotypes among patients with asthma. METHODS: This was a multicenter cross-sectional study of patients with severe asthma in Japan. Clinical data were obtained from medical records, and questionnaires were collected. Exhaled breath was sampled and subjected to thermal desorption gas chromatography-mass spectrometry (GC/MS). RESULTS: Using the decision tree established in the previous nationwide asthma cohort study, 245 patients with asthma were divided into five phenotypes and subjected to exhaled VOC analysis with 50 healthy controls (HCs). GC/MS detected 243 VOCs in exhaled breath samples, and 142 frequently detected VOCs (50% of all samples) were used for statistical analyses. Cluster analysis assigning the groups with similar VOC profile patterns showed the highest similarities between phenotypes 3 and 4 (early-onset asthma phenotypes), followed by the similarities between phenotypes 1 and 2 (late-onset asthma phenotypes). Comparisons between phenotypes 1-5 and HC revealed 19 VOCs, in which only methanesulfonic anhydride showed p < 0.05 adjusted by false discovery rate (FDR). Comparison of these phenotypes yielded several VOCs showing different trends (p < 0.05); however, no VOCs showed p < 0.05 adjusted by FDR. CONCLUSIONS: Exhaled VOC profiles may be useful for distinguishing asthma and asthma phenotypes; however, these findings need to be validated, and their pathological roles should be clarified.

Classifications of moderate to severe asthma phenotypes in Japan and analysis of serum biomarkers: A Nationwide Cohort Study in Japan (NHOM Asthma Study).

BACKGROUND: Asthma is a heterogeneous disease, and phenotyping can facilitate understanding of disease pathogenesis and direct appropriate asthma treatment. This nationwide cohort study aimed to phenotype asthma patients in Japan and identify potential biomarkers to classify the phenotypes. METHODS: Adult asthma patients (n = 1925) from 27 national hospitals in Japan were enrolled and divided into Global Initiative for Asthma (GINA) steps 4 or 5 (GINA 4, 5) and GINA Steps 1, 2, or 3 (GINA 1-3) for therapy. Clinical data and questionnaires were collected. Biomarker levels among GINA 4, 5 patients were measured. Ward's minimum variance hierarchical clustering method and tree analysis were performed for phenotyping. Analysis of variance, the Kruskal-Wallis, and chi-square tests were used to compare cluster differences. RESULTS: The following five clusters were identified: 1) late-onset, old, less-atopic; 2) late-onset, old, eosinophilic, low FEV1; 3) early-onset, long-duration, atopic, poorly controlled; 4) early-onset, young, female-dominant, atopic; and 5) female-dominant, T1/T2-mixed, most severe. Age of onset, disease duration, blood eosinophils and neutrophils, asthma control questionnaire Sum 6, number of controllers, FEV1, body mass index (BMI), and hypertension were the phenotype-classifying variables determined by tree analysis that assigned 79.5% to the appropriate cluster. Among the cytokines measured, IL-1RA, YKL40/CHI3L1, IP-10/CXCL10, RANTES/CCL5, and TIMP-1 were useful biomarkers for classifying GINA 4, 5 phenotypes. CONCLUSIONS: Five distinct phenotypes were identified for moderate to severe asthma and may be classified using clinical and molecular variables (Registered in UMIN-CTR; UMIN000027776.).

Nanofluidic Model Membrane for the Single-Molecule Observation of Membrane Proteins.

Membrane proteins play essential roles in the cell, and they constitute one of the most important targets of drugs. Studying membrane proteins in a controlled model membrane environment can provide unambiguous, quantitative information on their molecular properties and functions. However, reconstituting membrane proteins in a model system poses formidable technological challenges. Here, we developed a novel model membrane platform for highly sensitive observation of membrane proteins by combining a micropatterned lipid membrane and a nanofluidic channel. A micropatterned model membrane was generated by lithographically integrating a polymerized lipid bilayer and a natural (fluid) lipid bilayer. A nanofluidic channel having a defined thickness was formed between the fluid bilayer and a polydimethylsiloxane (PDMS) slab by attaching the polymeric bilayer and PDMS slab using an adhesion layer composed of silica nanoparticles that are coated with a biocompatible polymer brush. As we reconstituted rhodopsin (Rh), a G-protein-coupled receptor (GPCR), from a detergent-solubilized state into the fluid bilayer, only successfully reconstituted Rh molecules diffused laterally in the lipid bilayer and migrated into the nanogap junction, where they could be observed with a vastly improved signal-to-background ratio. The nanogap junction effectively separates the sites of reconstitution and observation and provides a novel platform for studying the molecular properties and functions of membrane proteins at the single-molecular level.

Photosynthetic Model Membranes of Natural Plant Thylakoid Embedded in a Patterned Polymeric Lipid Bilayer.

Thylakoid membranes in the chloroplast of plants, algae, and cyanobacteria are the powerhouse of photosynthesis, capturing solar energy and converting it into chemical energy. Although their structures and functions have been extensively studied, the intrinsically heterogeneous and dynamic nature of the membrane structures is still not fully understood. Investigating native thylakoid membranes in vivo is difficult due to their small size and limited external access to the chloroplast interior, while the bottom-up approaches based on model systems have been hampered by the sheer complexity of the native membrane. Here, we try to fill the gap by reconstituting the whole thylakoid membrane into a patterned substrate-supported planer bilayer. A mixture of thylakoid membrane purified from spinach leaves and synthetic phospholipid 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) vesicles spontaneously formed a laterally continuous and fluid two-dimensional (2D) membrane in the scaffold of the patterned polymeric bilayer. Chlorophyll fluorescence arising from photosystem II (PSII) recovered after photobleaching, suggesting that the membrane components are laterally mobile. The reversible changes of chlorophyll fluorescence in the presence of the electron acceptors and/or inhibitors indicated that the electron transfer activity of PSII was retained. Furthermore, we confirmed the electron transfer activity of photosystem I (PSI) by observing the generation of nicotinamide adenine dinucleotide phosphate (NADPH) in the presence of water-soluble ferredoxin and ferredoxin-NADP+ reductase. The lateral mobility of membrane-bound molecules and the functional reconstitution of major photosystems provide evidence that our hybrid thylakoid membranes could be an excellent experimental platform to study the 2D molecular organization and machinery of photosynthesis.

Alteration of Membrane Physicochemical Properties by Two Factors for Membrane Protein Integration.

After a nascent chain of a membrane protein emerges from the ribosomal tunnel, the protein is integrated into the cell membrane. This process is controlled by a series of proteinaceous molecular devices, such as signal recognition particles and Sec translocons. In addition to these proteins, we discovered two endogenous components regulating membrane protein integration in the inner membrane of Escherichia coli. The integration is blocked by diacylglycerol (DAG), whereas the blocking is relieved by a glycolipid named membrane protein integrase (MPIase). Here, we investigated the influence of these integration-blocking and integration-promoting factors on the physicochemical properties of membrane lipids via solid-state NMR and fluorescence measurements. These factors did not have destructive effects on membrane morphology because the membrane maintained its lamellar structure and did not fuse in the presence of DAG and/or MPIase at their effective concentrations. We next focused on membrane flexibility. DAG did not affect the mobility of the membrane surface, whereas the sugar chain in MPIase was highly mobile and enhanced the flexibility of membrane lipid headgroups. Comparison with a synthetic MPIase analog revealed the effects of the long sugar chain on membrane properties. The acyl chain order inside the membrane was increased by DAG, whereas the increase was cancelled by the addition of MPIase. MPIase also loosened the membrane lipid packing. Focusing on the transbilayer movement, MPIase reduced the rapid flip-flop motion of DAG. On the other hand, MPIase could not compensate for the diminished lateral diffusion by DAG. These results suggest that by manipulating the membrane lipids dynamics, DAG inhibits the protein from contacting the inner membrane, whereas the flexible long sugar chain of MPIase increases the opportunity for interaction between the membrane and the protein, leading to membrane integration of the newly formed protein.

Self-Spreading of Phospholipid Bilayer in a Patterned Framework of Polymeric Bilayer.

Phospholipid bilayers spontaneously spread on a hydrophilic substrate such as glass in aqueous solution due to the energetic gain of surface wetting. This process (self-spreading) was utilized to form a patterned model biological membrane containing reconstituted membrane proteins. A mechanically stable framework of a polymerized lipid bilayer was first generated by the lithographic polymerization of a diacetylene phospholipid. Then, natural lipid membranes (fluid bilayers) were introduced into the channels between polymeric bilayers by the self-spreading from a phospholipid reservoir. The spreading velocity could be fitted into a slope of -0.5 in a double logarithmic plot versus time due to the balance between the spreading force and resistive drag. The preformed polymeric bilayer accelerated the spreading by the energetic gain of covering hydrophobic edges with a lipid bilayer. At the same time, the domains of the polymeric bilayer obstructed spreading, and the spreading velocity linearly decreased with their fractional coverage. Above the critical coverage of ca. 50%, self-spreading was completely blocked (percolation threshold) and the fluid bilayer was confined in the polymer-free regions. Nonspecific adsorption of lipids onto the surface of polymeric bilayers was negligible, which enabled a heightened signal-to-background ratio in the reconstitution and observation of membrane proteins. Self-spread bilayers had a higher density of lipids than those formed by the spontaneous rupture of vesicles (vesicle fusion), presumably due to the continual supply of lipid molecules from the reservoir. These features give the self-spreading important advantages for preparing patterned model membranes with reconstituted membrane proteins.

Hybrid Model Membrane Combining Micropatterned Lipid Bilayer and Hydrophilic Polymer Brush.

Substrate-supported planar lipid bilayers (SPBs) are being utilized as a versatile model system of the biological membrane. However, the proximity between the solid support and membrane limits utility of SPBs for the functional analyses of membrane proteins. Here, we present a model membrane that can enlarge the distance between the substrate surface and the membrane by combining a stable scaffold of polymerized lipid bilayer with a hydrophilic polymer brush. A micropatterned SPB was generated by the lithographic polymerization of diacetylene lipids and subsequent incorporation of natural (fluid) lipid bilayers. Hydrophilic polymer brush of poly-2-methacryloyloxyethyl phosphorylcholine (poly(MPC)) was formed on the surface of polymeric bilayer by the in situ atom transfer radical polymerization (ATRP) in aqueous solution, in the presence of embedded fluid lipid bilayers. A model membrane protein (Haloquadratum walsbyi bacteriorhodopsin: HwBR) could be reconstituted into the polymer brush-supported bilayers with significantly reduced immobile molecules. Furthermore, the polymer brush terminals could be functionalized by successively polymerizing MPC and 2-aminoethyl methacrylate (AMA). The reactive amine moiety of poly(AMA) enables to conjugate a wide range of biological molecules and surfaces to the membrane. The combination of micropatterned bilayer and polymer brush mimics the two- and three-dimensional structures of the biological membrane, providing a platform to assay membrane proteins in a truly biomimetic environment.

Protective Effects of Bisoprolol against Acute Exacerbation in Moderate-to-Severe Chronic Obstructive Pulmonary Disease.

Although recent retrospective studies suggested that the use of ß-blockers appears to help improve the mortality rate and decrease the rate of exacerbation in chronic obstructive pulmonary disease (COPD) patients with heart failure, the effects of ß-blockers on COPD patients without heart failure have not been established. Based on previous reports, we have launched a multicenter, prospective, single-arm phase II study to evaluate the preventive effect of the cardioselective ß-blocker bisoprolol in COPD exacerbation, in Japanese individuals with moderate-to-severe COPD who do not have heart failure but do have hypertension requiring the use of medication. The primary endpoint is the rate of mild-to-severe COPD exacerbation. The results of this study will clarify whether bisoprolol can prevent exacerbation in COPD patients without heart failure.

The Role of the Prod1 Membrane Anchor in Newt Limb Regeneration.

Prod1 is a protein that regulates limb regeneration in salamanders by determining the direction of limb growth. Prod1 is attached to the membrane by a glycosylphosphatidylinositol (GPI) anchor, but the role of membrane anchoring in the limb regeneration process is poorly understood. In this study, we investigated the functional role of the anchoring of Prod1 to the membrane by using its synthetic mimics in combination with solid-state NMR spectroscopy and fluorescent microscopy techniques. Anchoring did not affect the three-dimensional structure of Prod1 but did induce aggregation by aligning the molecules and drastically reducing the molecular motion on the two-dimensional membrane surface. Interestingly, aggregated Prod1 interacted with Prod1 molecules tethered on the surface of opposing membranes, inducing membrane adhesion. Our results strongly suggest that anchoring of the salamander-specific protein Prod1 assists cell adhesion in the limb regeneration process.

Genetic and environmental factors associated with bronchial asthma.

Many genetic and environmental factors associated with bronchial asthma have been investigated. These include disease-related genome, obesity, smoking, and rhinitis. Several susceptibility loci for bronchial asthma were recently identified by genome-wide association study(GWAS). GWAS requires future functional analysis. Obesity, smoking, and rhinitis are each risk factor for development of asthma. Moreover, obesity as well as smoking is asso- ciated with severe or uncontrolled asthma.

Evaluating the Raftophilicity of Rhodopsin Photoreceptor in a Patterned Model Membrane.

Lipid rafts in the cell membrane are believed to affect various membrane functions, including the signaling by G-protein coupled receptors (GPCRs). However, the regulatory roles of lipid rafts on GPCRs' functions are still poorly understood, partially owing to the lack of the methods to quantitatively evaluate the affinity of membrane proteins to lipid raft (raftophilicity). Here, we describe a methodology to gauge the raftophilicity of a representative GPCR in vertebrate photoreceptor, i.e., rhodopsin (Rh), and its cognate G protein transducin (Gt) by using a patterned model membrane. We generated a substrate-supported planar lipid bilayer that has patterned regions of liquid-ordered (Lo) and liquid-disordered (Ld) membrane domains. We reconstituted Rh and Gt into the patterned membrane and observed their lateral distribution and diffusion. Mobile and functional Rh molecules could be reconstituted through the rapid dilution of solubilized Rh, by optimizing the reconstitution conditions including the chamber design, protein/detergent concentrations, and solution mixing. We determined the partition and diffusion coefficients of Rh and Gt in the Lo-rich and Ld-rich regions. Both Rh and Gt were predominantly localized in the Ld phase, suggesting their low affinity to lipid rafts. Patterned model membrane offers a robust and scalable platform for systematically and quantitatively studying the functional roles of lipid rafts in biological membranes including retinal disk membranes.

Contrasting roles for the receptor for advanced glycation end-products on structural cells in allergic airway inflammation vs. airway hyperresponsiveness.

The receptor for advanced glycation end-products (RAGE) is a multiligand receptor that belongs to the immunoglobulin superfamily. RAGE is reported to be involved in various inflammatory disorders; however, studies that address the role of RAGE in allergic airway disease are inconclusive. RAGE-sufficient (RAGE+/+) and RAGE-deficient (RAGE-/-) mice were sensitized to ovalbumin, and airway responses were monitored after ovalbumin challenge. RAGE-/- mice showed reduced eosinophilic inflammation and goblet cell metaplasia, lower T helper type 2 (Th2) cytokine production from spleen and peribronchial lymph node mononuclear cells, and lower numbers of group 2 innate lymphoid cells in the lung compared with RAGE+/+ mice following sensitization and challenge. Experiments using irradiated, chimeric mice showed that the mice expressing RAGE on radio-resistant structural cells but not hematopoietic cells developed allergic airway inflammation; however, the mice expressing RAGE on hematopoietic cells but not structural cells showed reduced airway inflammation. In contrast, absence of RAGE expression on structural cells enhanced innate airway hyperresponsiveness (AHR). In the absence of RAGE, increased interleukin (IL)-33 levels in the lung were detected, and blockade of IL-33 receptor ST2 suppressed innate AHR in RAGE-/- mice. These data identify the importance of RAGE expressed on lung structural cells in the development of allergic airway inflammation, T helper type 2 cell activation, and group 2 innate lymphoid cell accumulation in the airways. RAGE on lung structural cells also regulated innate AHR, likely through the IL-33-ST2 pathway. Thus manipulating RAGE represents a novel therapeutic target in controlling allergic airway responses.

Effect of a cysteinyl leukotriene receptor antagonist on experimental emphysema and asthma combined with emphysema.

The incidence of overlapping bronchial asthma and chronic obstructive pulmonary disease has increased in recent years. Cysteinyl leukotrienes (CysLTs) play an important role in asthma, and the type 1 CysLT receptor (CysLT1R) is expressed by many inflammatory cells. We evaluated the effect of montelukast, a CysLT1R antagonist, on mouse models of asthma, porcine pancreatic elastase (PPE)-induced emphysema, and asthma combined with emphysema. Mice were sensitized with ovalbumin (OVA) on Days 0 and 14 and subsequently challenged with OVA on Days 28, 29, and 30. Pulmonary emphysema was induced by intratracheal instillation of PPE on Day 25. Mice were treated subcutaneously with montelukast or vehicle from Day 25 to Day 31. Airway hyperresponsiveness (AHR), static compliance; the number of inflammatory cells, the levels of cytokines, chemokines, LTs, and perforin in the bronchoalveolar lavage fluid, and the quantitative morphometry of lung sections were analyzed on Day 32. Treatment with montelukast significantly attenuated the AHR and eosinophilic airway inflammation in OVA-sensitized and OVA-challenged mice. Administration of montelukast significantly reduced the AHR, static compliance, and neutrophilic airway inflammation, while attenuating emphysematous lung changes, in PPE-treated mice. In PPE-treated mice subjected to allergen sensitization and challenges, montelukast significantly suppressed the AHR, static compliance, and eosinophilic and neutrophilic airway inflammation in addition to the development of experimentally induced emphysema in the lungs. Our data suggest that CysLT1R antagonists may be effective in ameliorating the consequences of PPE-induced lung damage and the changes that follow allergen sensitization and challenges.

An immunocompetent case of chronic pulmonary aspergillosis caused by Aspergillusviridinutans.

We encountered an extremely rare immunocompetent case of chronic pulmonary aspergillosis (CPA) caused by Aspergillus viridinutans. A 74-year-old woman was admitted with fever and hemoptysis. Chest computed tomography revealed a nodule in the left upper lobe. Bronchoscopy was performed, and the transbronchial biopsy specimen revealed Aspergillus fungi. Treatment of the nodule was initially ineffective with voriconazole but effective with liposomal amphotericin B. The causative organism was later identified as A. viridinutans based on the gene sequence of ß-tubulin. This is the first immunocompetent case of CPA caused by A. viridinutans.

Predictors of exacerbation in Japanese patients with severe asthma: Analysis of the severe asthma research program (Okayama-SARP) cohort.

BACKGROUND: Because exacerbation of severe asthma decreases patients' quality of life, this study aimed to identify predictive factors for asthma exacerbation. METHODS: Japanese patients with severe asthma requiring treatment according to the Global Initiative for Asthma (GINA) guidelines ≥ Step 4 between January 2018 and August 2021 were prospectively enrolled and followed up for one year at facilities participating in the Okayama Respiratory Disease Study Group (Okayama Severe Asthma Research Program). RESULTS: A total of 85 patients (29 men and 56 women) were included. The median age was 64 (interquartile range [IQR], 51-72) years. Treatment according to GINA Steps 4 and 5 was required in 29 and 56 patients, respectively, and 44 patients (51.8%) were treated with biologics. The median peripheral-blood eosinophil count, fractional exhaled nitric oxide, IgE level, and percent predicted FEV1 (%FEV1) at enrollment were 204 (IQR, 49-436)/µL, 28 (IQR, 15-43) ppb, 172 (IQR, 56-473) IU/mL, and 80.0 (IQR, 61.1-96.1) %, respectively. Exacerbation during the previous year, asthma control test (ACT) score <20, %FEV1 <60%, and serum IL-10 level >6.7 pg/mL were associated with exacerbation during the observation period. CONCLUSIONS: Exacerbation during the previous year, low ACT score, and low %FEV1 were predictive factors of future exacerbation, even in a cohort with >50% of patients treated with biologics. Furthermore, high serum IL-10 levels might be a new predictive factor.

Inhibition of neutrophil elastase attenuates airway hyperresponsiveness and inflammation in a mouse model of secondary allergen challenge: neutrophil elastase inhibition attenuates allergic airway responses.

BACKGROUND: Chronic asthma is often associated with neutrophilic infiltration in the airways. Neutrophils contain elastase, a potent secretagogue in the airways, nonetheless the role for neutrophil elastase as well as neutrophilic inflammation in allergen-induced airway responses is not well defined. In this study, we have investigated the impact of neutrophil elastase inhibition on the development of allergic airway inflammation and airway hyperresponsiveness (AHR) in previously sensitized and challenged mice. METHODS: BALB/c mice were sensitized and challenged (primary) with ovalbumin (OVA). Six weeks later, a single OVA aerosol (secondary challenge) was delivered and airway inflammation and airway responses were monitored 6 and 48 hrs later. An inhibitor of neutrophil elastase was administered prior to secondary challenge. RESULTS: Mice developed a two-phase airway inflammatory response after secondary allergen challenge, one neutrophilic at 6 hr and the other eosinophilic, at 48 hr. PAR-2 expression in the lung tissues was enhanced following secondary challenge, and that PAR-2 intracellular expression on peribronchial lymph node (PBLN) T cells was also increased following allergen challenge of sensitized mice. Inhibition of neutrophil elastase significantly attenuated AHR, goblet cell metaplasia, and inflammatory cell accumulation in the airways following secondary OVA challenge. Levels of IL-4, IL-5 and IL-13, and eotaxin in BAL fluid 6 hr after secondary allergen challenge were significantly suppressed by the treatment. At 48 hr, treatment with the neutrophil elastase inhibitor significantly reduced the levels of IL-13 and TGF-ß1 in the BAL fluid. In parallel, in vitro IL-13 production was significantly inhibited in spleen cells from sensitized mice. CONCLUSION: These data indicate that neutrophil elastase plays an important role in the development of allergic airway inflammation and hyperresponsiveness, and would suggest that the neutrophil elastase inhibitor reduced AHR to inhaled methacholine indicating the potential for its use as a modulator of the immune/inflammatory response in both the neutrophil- and eosinophil-dominant phases of the response to secondary allergen challenge.

IL-17A is essential to the development of elastase-induced pulmonary inflammation and emphysema in mice.

BACKGROUND: Pulmonary emphysema is characterized by alveolar destruction and persistent inflammation of the airways. Although IL-17A contributes to many chronic inflammatory diseases, it's role in the inflammatory response of elastase-induced emphysema remains unclear. METHODS: In a model of elastase-induced pulmonary emphysema we examined the response of IL-17A-deficient mice, monitoring airway inflammation, static compliance, lung histology and levels of neutrophil-related chemokine and pro-inflammatory cytokines in bronchoalveolar lavage (BAL) fluid. RESULTS: Wild-type mice developed emphysematous changes in the lung tissue on day 21 after elastase treatment, whereas emphysematous changes were decreased in IL-17A-deficient mice compared to wild-type mice. Neutrophilia in BAL fluid, seen in elastase-treated wild-type mice, was reduced in elastase-treated IL-17A-deficient mice on day 4, associated with decreased levels of KC, MIP-2 and IL-1 beta. Elastase-treated wild-type mice showed increased IL-17A levels as well as increased numbers of IL-17A+ CD4 T cells in the lung in the initial period following elastase treatment. CONCLUSIONS: These data identify the important contribution of IL-17A in the development of elastase-induced pulmonary inflammation and emphysema. Targeting IL-17A in emphysema may be a potential therapeutic strategy for delaying disease progression.

Radiation-Induced Lung Injury With Lung Cancer Treated With the Combination Therapy of Nintedanib and Dexamethasone.

Radiation-induced lung injury (RILI) associated with lung cancer becomes refractory. Nintedanib is a multi-kinase inhibitor that suppresses the development of pulmonary fibrosis. Herein, we report a case of RILI with progressive pulmonary fibrosis after stereotactic body radiation therapy in a 70-year-old man with lung cancer. The patient responded well to the initial prednisolone therapy but became resistant during tapering. The combination therapy of nintedanib and dexamethasone resulted in a temporary improvement in RILI. Nintedanib is not a standard therapy for RILI, and further investigation is needed to evaluate the effects of nintedanib on RILI complicated by lung cancer.

Retarded Diffusion and Confinement of Membrane-Bound Molecules in a Patterned Hybrid Membrane of Phospholipid Bilayers and Monolayers.

The biological membrane is a complex two-dimensional fluid, in which various molecular interactions regulate the lateral diffusion of membrane-associated molecules. Pinning of membrane proteins or lipids by extra-membrane proteins impedes the diffusion. In addition, coupling between two monolayer leaflets within a phospholipid bilayer via interdigitation plays important roles, though this effect remains elusive. Here, we fabricate a substrate-supported model membrane with patterned bilayer/monolayer regions to explore the influences of interleaflet coupling. A patterned monolayer of polymerized diacetylene phospholipid, 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine (DiynePC), was lithographically generated and used to form patterned lipid bilayers and monolayers. A phospholipid monolayer was formed on top of the polymerized monolayer. The bilayer/monolayer hybrid membrane was continuous and fluid, but lateral diffusion in the monolayer region was significantly retarded, suggesting the influences of interleaflet coupling. We reconstituted photoreceptor rhodopsin (Rh) and G-protein transducin (Gt) as model transmembrane and peripheral proteins. Rh diffused laterally only in the bilayer region, whereas Gt diffused in both bilayer and monolayer regions. The patterned hybrid bilayer/monolayer membrane reproduces the retarded diffusion and confinement of membrane-bound molecules in a controlled manner and provides insight into the physicochemical and functional roles of semipermeable corrals in the cell membrane.