Severe Lung Inflammation Research Articles

Pulmonary Thromboembolism in COVID-19: Venous Thromboembolism or Arterial Thrombosis?

PurposeTo investigate CT pulmonary angiography findings of pulmonary thromboembolism (PTE) in coronavirus disease 2019 (COVID-19) and its association with clinical and radiologic conditions.Materials and MethodsThis retrospective study includes 109 hospitalized patients with COVID-19 who underwent CT pulmonary angiography for suspected PTE from March 20 to May 3, 2020. Data were collected from our PACS. CT pulmonary angiography findings of PTE were evaluated. On the basis of the presence or absence of PTE, patients were divided into two groups, and their clinical and radiologic conditions were compared using the Mann–Whitney U test and χ2 test.ResultsThe study population comprised 82 men and 19 women, with a mean age of 64.1 years ± 15.0 (95% confidence interval [CI]: 60.4, 67.6) years. CT pulmonary angiography was performed 19.8 days ± 6.1 (95% CI: 18.1, 20.2) after symptom onset and 10.5 days ± 3.8 (95% CI: 10.2, 12.9) after admission. Of 101 patients, 41 had PTE (40.6%). PTE was mostly bilateral or only right (37/41 [90.2%]), mainly involved segmental (37/41 [90.2%]) or subsegmental (25/41 [61.0%]) arteries and affected mainly the branches of the lower lobe (30/41 [73.2%]). Parenchymal segments supplied by segmental arteries with PTE showed a prevalent consolidation pattern (25/37 [67.6%]). Deep vein thrombosis was present only in five of 41 (12.2%) patients. Comparing groups with and without PTE, no significant difference was observed in age, sex, symptom onset, comorbidities, tumor history, use of respiratory supports, activated partial thromboplastin time, prothrombin time, and deep vein thrombosis. Conversely, differences were evaluated in CT lesion score (15.7 ± 1.4 [95% CI: 15.3, 16.1] vs 14.1 ± 1.1 [95% CI: 13.8, 14.4]; P = .035), d-dimer level (P < .001), lactate dehydrogenase level (P < .001), and C-reactive protein level (P = .042).ConclusionPTE in COVID-19 involves mainly the segmental and subsegmental arteries of segments affected by consolidations in patients with more severe lung disease. The authors hypothesize that the development of PTE in COVID-19 might be a pulmonary artery thrombosis because of severe lung inflammation and hypercoagulability rather than thromboembolism.© RSNA, 2020

First person – Stephen Kershaw and David Morgan

ABSTRACT First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping early-career researchers promote themselves alongside their papers. Stephen Kershaw and David Morgan are co-first authors on ‘Glucocorticoids inhibit cell migration through a novel, non-transcriptional mechanism involving HDAC6’, published in JCS. Stephen is a postdoc in the lab of Dr Claus Jorgensen at the Cancer Research UK Manchester Institute investigating the role of intra-tumour heterogeneity on genetic dependencies in pancreatic ductal adenocarcinoma. David is a postdoc in the lab of Prof. Tracy Hussell at Manchester Collaborative Centre for Inflammation, Lydia Becker Institute of Immunology and Inflammation, The University of Manchester, UK, investigating how resolution of severe lung inflammation impacts alveolar macrophage function, and defining the immune landscape of adenoid cystic carcinoma.

MicroRNA‑93 contributes to the suppression of lung inflammatory responses in LPS‑induced acute lung injury in mice via the TLR4/MyD88/NF‑κB signaling pathway.

Acute lung injury (ALI) is a severe inflammatory lung disease with a rapid onset. The anti-inflammatory functions of microRNA-93 (miRNA/miR-93) have been described in various types of tissue injury and disease. However, the biological role of miR-93 and its molecular mechanisms underlying the initiation and progression of ALI have not yet been reported, at least to the best of our knowledge. The present study aimed to investigate the regulatory effects exerted by miR-93 in ALI. Using an in vivo murine model of ALI induced by lipopolysaccharide (LPS), miR-93 expression was found to be downregulated in the lung tissues and bronchoalveolar lavage fluid (BALF) compared with the control group. Following agomiR-93 injection, it was observed that agomiR-93 attenuated lung injury, as evidenced by decreased lung permeability, a reduced lung wet/dry weight ratio and an increased survival rate of the mice. Concomitantly, agomiR-93 significantly reduced LPS-induced the interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α levels in BALF. Of note, Toll-like receptor 4 (TLR4), an upstream regulator of the nuclear factor (NF)-κB signaling pathway, was directly suppressed by miR-93 in RAW 264.7 cells. Importantly, agomiR-93 induced a significant suppression of the TLR4/myeloid differentiation primary response 88 (MyD88)/NF-κB signaling pathway, as demonstrated by the downregulation of MyD88, and the phosphorylation of IκB-α and p65 in the lung tissues of mice with ALI. Taken together, the findings of the present study indicate that miR-93 attenutes LPS-induced lung injury by regulating the TLR4/MyD88/NF-κB signaling pathway, suggesting that miR-93 may prove to be a potential therapeutic target for ALI.

Modulation of fear behavior and neuroimmune alterations in house dust mite exposed A/J mice, a model of severe asthma

Fear-associated conditions such as posttraumatic stress disorder (PTSD) and panic disorder (PD) are highly prevalent. There is considerable interest in understanding contributory risk and vulnerability factors. Accumulating evidence suggests that chronically elevated inflammatory load may be a potential risk factor for these disorders. In this regard, an association of asthma, a chronic inflammatory condition, with PTSD and PD has been reported. Symptoms of PD and PTSD are more prevalent in severe asthmatics, compared to those with mild or moderate asthma suggesting that factors that influence the severity of asthma, may also influence susceptibility to the development of fear-related disorders. There has been relatively little progress in identifying contributory factors and underlying mechanisms, particularly, the translation of severe asthma-associated lung inflammation to central neuroimmune alterations and behavioral manifestations remains unclear. The current study investigated the expression of behaviors relevant to PD and PTSD (CO2 inhalation and fear conditioning/extinction) in A/J mice using a model of severe allergic asthma associated with a mixed T helper 2 (Th2) and Th17 immune response. We also investigated the accumulation of Th2- and Th17-cytokine expressing cells in lung and brain tissue, microglial alterations, as well as neuronal activation marker, delta FosB (ΔFosB)) in fear and panic regulatory brain areas. HDM-exposed mice elicited higher freezing during fear extinction. CO2-associated spontaneous and conditioned freezing, as well as anxiety or depression-relevant exploratory and coping behaviors were not altered by HDM treatment. A significant increase in brain Th17-associated inflammatory mediators was observed prior to behavioral testing, accompanied by microglial alterations in specialized blood brain barrier-compromised circumventricular area, subfornical organ. Post extinction measurements revealed increased ΔFosB staining within the medial prefrontal cortex and basolateral amygdala in HDM-treated mice. Collectively, our data show modulation of brain immune mechanisms and fear circuits by peripheral airway inflammation, and is relevant to understanding the risk and comorbidity of asthma with fear-associated disorders such as PTSD.

Radiographic and Clinical Features of Children With Coronavirus Disease (COVID-19) Pneumonia

Objective: The purpose of this study was to investigate chest computed tomography (CT) findings in children with coronavirus disease-19 (COVID-19) pneumonia in our hospital. Methods: This study included 22 pediatric patients with confirmed COVID-19 from January to March, 2020. The chest CT images and clinical data were reviewed. Results: The most prevalent presenting symptoms were fever (64%) and cough (59%), and a mildly elevated mean (SD) C-reactive protein (CRP) level of 11.22(11.06) and erythrocyte sedimentation rateof 18.8(15.17) were detected. The major CT abnormalities observed were mixed ground-glass opacity and consolidation lesions (36%), consolidations (32%), and groundglass opacities (14%). Peripheral distribution (45%) of lung lesions was predominant. Most of the lesions were multilobar(68%), with an average of three lung segments involved. Conclusion: Children with COVID-19 had relatively milder symptoms and less severe lung inflammation than adults.Chest CT plays an important role in the management of children with COVID-19 pneumonia.

Transcriptome Profiling of Lung Innate Immune Responses Potentially Associated With the Pathogenesis of Acinetobacter baumannii Acute Lethal Pneumonia.

Acinetobacter baumannii is one of the dominating causes of nosocomial pneumonia, however, very little is known about the host immune response associated with pathogenesis of A. baumannii infection. Here, we used a hypervirulent A. baumannii to establish an acute lethal pneumonia, supported by high bacterial burdens, severe inflammatory cells infiltration and lung damage. The lung transcriptome changes in response to A. baumannii lethal pneumonia were detected by RNA sequencing. The results showed that 6,288 host genes changed expression, with 3,313 upregulated genes and 2,975 downregulated genes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that genes related to TNF, cytokine-cytokine receptor interaction, Toll-like receptor, NOD-like receptor, NF-κB, Jak-STAT, HIF-1 signaling pathways, apoptosis, and phagosome were significantly upregulated. Whereas, genes associated with PI3K-AKT signaling pathway, glycolysis/gluconeogenesis, amino acid and fatty acid metabolism were downregulated. Immune cell typing highlighted the inflammatory response of innate immune cells headed by neutrophils. The reliability of RNA sequencing results were verified with selected differentially expressed genes by real-time PCR. This work provides an insight into the pathogenesis of lethal A. baumannii lung infection.

Ozone-Induced Aryl Hydrocarbon Receptor Activation Controls Lung Inflammation via Interleukin-22 Modulation.

Airborne ozone exposure causes severe lung injury and inflammation. The aryl hydrocarbon Receptor (AhR) (1), activated in pollutant-induced inflammation, is critical for cytokine production, especially IL-22 and IL-17A. The role of AhR in ozone-induced lung inflammation is unknown. We report here that chronic ozone exposure activates AhR with increased tryptophan and lipoxin A4 production in mice. AhR−/− mice show increased lung inflammation, airway hyperresponsiveness, and tissue remodeling with an increased recruitment of IL-17A and IL-22-expressing cells in comparison to control mice. IL-17A- and IL-22-neutralizing antibodies attenuate lung inflammation in AhR−/− and control mice. Enhanced lung inflammation and recruitment of ILC3, ILC2, and T cells were observed after T cell-specific AhR depletion using the AhRCD4cre-deficient mice. Together, the data demonstrate that ozone exposure activates AhR, which controls lung inflammation, airway hyperresponsiveness, and tissue remodeling via the reduction of IL-22 expression.

Deficiency of HIF-1α enhances influenza A virus replication by promoting autophagy in alveolar type II epithelial cells

ABSTRACT Infection of influenza A virus (IAV) can trigger exaggerated pulmonary inflammation and induce acute lung injury (ALI). Limiting IAV replication and alleviation of pulmonary inflammation are two important therapeutic strategies for influenza virus infection. Recent studies have shown that hypoxia inducible factor-1α (HIF-1α) is an essential factor for the development and repair of ALI; however, the role and the underlying mechanisms of HIF-1α in IAV-induced ALI remain elusive. Here, we demonstrated that lung epithelial cell-specific Hif1α knockout mice infected with IAV developed more lung IAV replication and severe lung inflammation, which led to increased mortality compared to IAV-infected control mice. Moreover, knockdown of HIF1A in A549 cells (human alveolar type II epithelial cell line) promoted IAV replication in vitro. Mechanistically, knockdown of HIF1A reduced glycolysis by regulating transcription of glycolysis-related enzymes, which subsequently activated the AMPKα-ULK1 signalling pathway. Interestingly, AMPKα-ULK1 signalling promoted autophagy and augmented IAV replication. Taken together, deficiency of HIF-1α in lung epithelial cells reduces glycolysis and enhances AMPKα-ULK1-mediated autophagy, which finally facilitates IAV replication. These findings have deepened our understanding of the role of HIF-1α in regulating IAV replication and provided us novel therapeutic targets for combating influenza infection.

The pathophysiology of the haematological manifestations of COVID-19 : a review

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and the coronavirus disease 2019 (COVID-19) it causes, are associated with several haematological abnormalities which manifest as some of the clinical syndromes seen in COVID-19. The main organ affected by COVID-19 is the lung, where an intense inflammatory response occurs in the alveoli and the lung vasculature. This may result in severely compromised gaseous exchange consistent with acute respiratory disease syndrome (ARDS). Multiple organ failure and death may ensue. The extent to which SARS-CoV-2 directly affects erythroid, granulocytic and monocytic progenitors is unknown, however related Coronaviridae have previously been shown to infect megakaryocytes and their progenitors. Furthermore, SARS-CoV-2 may directly infect lymphocytes or monocytes causing the production of cytokines and chemokines, which then cause lymphocyte death and lymphopenia. The quantitative changes seen in monocytes and granulocytes are at least partly due to the marked increase in various cytokines also called the “cytokine storm” and the downstream effects of these cytokines. A COVID-19-associated coagulopathy (CAC) may occur, which ranges from a mild derangement of laboratory haemostatic tests, through to sepsis-induced coagulopathy (SIC), and later, frank disseminated intravascular coagulation (DIC). The most common and devastating haemostatic abnormality is widespread thrombosis, which is associated with severe lung inflammation, hypoxia and death. COVID-19 is associated with immune perturbation states namely, immune thrombocytopenia (ITP), Guillain-Barré syndrome, the anti-phospholipid syndrome and a Kawasaki-like syndrome in children. The pathophysiology of the haematological abnormalities seen in COVID-19 is briefly reviewed in this article.

B Cell-Based Vaccine Transduced With ESAT6-Expressing Vaccinia Virus and Presenting α-Galactosylceramide Is a Novel Vaccine Candidate Against ESAT6-Expressing Mycobacterial Diseases

Early secretory antigenic target-6 (ESAT6) is a potent immunogenic antigen expressed in Mycobacterium tuberculosis as well as in some non-tuberculous mycobacteria (NTM), such as M. kansasii. M. kansasii is one of the most clinically relevant species of NTM that causes mycobacterial lung disease, which is clinically indistinguishable from tuberculosis. In the current study, we designed a novel cell-based vaccine using B cells that were transduced with vaccinia virus expressing ESAT6 (vacESAT6), and presenting α-galactosylceramide (αGC), a ligand of invariant NKT cells. We found that B cells loaded with αGC had increased levels of CD80 and CD86 after in vitro stimulation with NKT cells. Immunization of mice with B/αGC/vacESAT6 induced CD4+ T cells producing TNF-α and IFN-γ in response to heat-killed M. tuberculosis. Immunization of mice with B/αGC/vacESAT6 ameliorated severe lung inflammation caused by M. kansasii infection. We also confirmed that immunization with B/αGC/vacESAT6 reduced M. kansasii bacterial burden in the lungs. In addition, therapeutic administration of B/αGC/vacESAT6 increased IFN-γ+ CD4+ T cells and inhibited the progression of lung pathology caused by M. kansasii infection. Thus, B/αGC/vacESAT6 could be a potent vaccine candidate for the prevention and treatment of ESAT6-expressing mycobacterial infection caused by M. kansasii.

Glycyrrhizin mitigates radiation-induced acute lung injury by inhibiting the HMGB1/TLR4 signalling pathway.

Radiation‐induced lung injury (RILI) is the major complication of thoracic radiation therapy, and no effective treatment is available. This study explored the role of high‐mobility group box 1 (HMGB1) in acute RILI and the therapeutic effect of glycyrrhizin, an inhibitor of HMGB1, on RILI. C57BL/6 mice received a 20 Gy dose of X‐ray radiation to the whole thorax with or without administration of glycyrrhizin. Severe lung inflammation was present 12 weeks after irradiation, although only a mild change was noted at 2 weeks and could be alleviated by administration of glycyrrhizin. Glycyrrhizin decreased the plasma concentrations of HMGB1 and sRAGE as well as TNF‐α, IL‐1β and IL‐6 levels in the bronchoalveolar lavage fluid (BALF). The expression of RAGE was decreased while that of TLR4 was significantly increased at 12 weeks, but not 2 weeks, after irradiation in mouse lung tissue. In vitro, the expression of TLR4 increased in RAW 264.7 cells after conditioning with the supernatant from the irradiated MLE‐12 cells containing HMGB1 but showed no change when conditioned medium without HMGB1 was used. However, conditioned culture had no effect on RAGE expression in RAW 264.7 cells. Glycyrrhizin also inhibited the related downstream transcription factors of HMGB/TLR4, such as NF‐κB, JNK and ERK1/2, in lung tissue and RAW 264.7 cells when TLR4 was activated. In conclusion, the HMGB1/TLR4 pathway mediates RILI and can be mitigated by glycyrrhizin.

CDK 4/6 inhibitors linked with severe lung inflammation

CDK 4/6 inhibitors linked with severe lung inflammation

Toll Like Receptor 4 Mediated Lymphocyte Imbalance Induces Nec-Induced Lung Injury.

Necrotizing enterocolitis (NEC) is the leading cause of death from gastrointestinal disease in premature infants, and is associated with the development of severe lung inflammation. The pathogenesis of NEC-induced lung injury remains unknown, yet infiltrating immune cells may play a role. In support of this possibility, we now show that NEC in mice and humans was associated with the development of profound lung injury that was characterized by an influx of Th17 cells and a reduction in T regulatory lymphocytes (Tregs). Importantly, the adoptive transfer of CD4 T cells isolated from lungs of mice with NEC into the lungs of immune incompetent mice (Rag1 mice) induced profound inflammation in the lung, while the depletion of Tregs exacerbated NEC induced lung injury, demonstrating that imbalance of Th17/Treg in the lung is required for the induction of injury. In seeking to define the mechanisms involved, the selective deletion of toll-like receptor 4 (TLR4) from the Sftpc1 pulmonary epithelial cells reversed lung injury, while TLR4 activation induced the Th17 recruiting chemokine (C-C motif) ligand 25 (CCL25) in the lungs of mice with NEC. Strikingly, the aerosolized inhibition of both CCL25 and TLR4 and the administration of all trans retinoic acid restored Tregs attenuated NEC-induced lung injury. In summary, we show that TLR4 activation in Surfactant protein C-1 (Sftpc1) cells disrupts the Treg/Th17 balance in the lung via CCL25 leading to lung injury after NEC and reveal that inhibition of TLR4 and stabilization of Th17/Treg balance in the neonatal lung may prevent this devastating complication of NEC.

Platelet PI3K Modulates Innate Leukocyte Extravasation during Acid-Induced Acute Lung Inflammation.

Blood platelets are increasingly recognized as modulators of leukocyte effector functions in various pathologies including acute lung injury (ALI). ALI is a life-threatening disease, caused by damage to the alveolar epi- and endothelium. Excessive accumulation of leukocytes leads to severe lung inflammation, resulting in impaired lung function and hypoxemia. Since leukocyte migration is modulated by activated platelets and phosphatidylinositol 3-kinase (PI3K) signaling is involved in platelet function, we aimed to elucidate the effect of PI3K on platelet-mediated immune responses. We generated a mouse model with a platelet-specific deletion of p85α, the most important regulatory subunit of the class IA PI3K, and evaluated platelet function and platelet-leukocyte interactions. Moreover, we analyzed the impact of platelet-specific p85α gene deficiency during sterile peritonitis and acid-induced ALI. In vitro analyses of platelets revealed that lack of p85α led to decreased downstream signaling and diminished expression of surface activation markers, for example, CD62P and CD63, as well as reduced platelet aggregation. Moreover, platelet PI3K essentially mediated direct interactions of platelets with monocytes and neutrophils. In mice, platelet-specific p85α deficiency prevented leukocyte infiltration into the peritoneum and the bronchoalveolar compartment during sterile peritonitis and ALI, respectively. Additionally, the release of the inflammatory cytokine interleukin-12/23 was diminished in platelet p85α-deficient mice during ALI. In contrast to PI3K, neither overexpression nor depletion of platelet phosphatase and tensin homolog, the endogenous antagonist of PI3K, significantly modulated platelet function. Our data indicate a crucial role of platelet PI3K signaling for leukocyte extravasation upon inflammatory stimuli in various diseases models.

Immunosuppression Reduces Lung Injury Caused by Mycoplasma pneumoniae Infection

The underlying mechanisms of Mycoplasma pneumoniae pneumonia (MPP) pathogenesis are not clearly understood. This study aimed to investigate the correlation between immune response and lung injury in MPP. The clinical characteristics of MPP were compared between patients treated with and without immunosuppressive chemotherapy, and demographic, clinical, and laboratory data were compared between patients with severe and mild MPP. To determine the effect of immune response on lung lesions, mouse MPP and immunosuppression models were established by intranasal inoculation of M129 and intraperitoneal injection of cyclophosphamide, respectively. Myeloperoxidase and oxidant–antioxidant enzyme activities were evaluated for mechanism studies. The immunosuppressant group had a lower incidence of MPP and fewer cases of severe MPP than the non-immunosuppressant group. The severe MPP group had a greater incidence of severe immune disorders than the mild MPP group. Relative to immunosuppressed mice, wild mice exhibited more severe inflammatory infiltration and lung injury as well as a significant increase in myeloperoxidase and malondialdehyde levels and a decrease in superoxide dismutase level after MP infection. In conclusion, immunological responses likely play a vital role in MPP pathogenesis. Lung injury occurring after MP infection—which might be caused by oxidant–antioxidant imbalance—can be reduced by immunosuppression.

Chronic inflammatory response in the rat lung to commonly used contrast agents for videofluoroscopy.

ObjectivesContrast agents (CAs) are essential for upper gastrointestinal and videofluoroscopic swallow studies (VFSSs). Recently, we reported that small amounts of Ba aspiration caused severe acute lung inflammation in a rodent model. However, the underlying molecular biological mechanisms of chronic response to CA aspiration remain unclear. The aims of this study were to explore the underlying molecular biological mechanisms of the chronic response to three kinds of CA aspiration on the lung.Study DesignAnimal model.MethodsEight‐week‐old male Sprague Dawley rats were divided into five groups (n = 6, each group). Three groups underwent tracheal instillation of one of three CAs: barium sulfate (Ba), ionic iodinated contrast agent (ICA), and nonionic iodinated contrast agent (NICA). A sham group was instilled with air and a control group was instilled with saline. All animals were euthanized 30 days after treatment and histological and gene analyses were performed.ResultsNo animal died after CA or sham/control aspiration. Ba particles remained after 30 days and caused histopathologic changes and inflammatory cell infiltration. Iodinated ICA and NICA did not result in perceptible histologic change. Expression of Tnf, an inflammatory cytokine was increased in only Ba aspirated rats (P = .0076). Other inflammatory cytokines and fibrosis‐related genes did not alter between groups.ConclusionAspirated Ba particles did not clear from the lung within a month and caused mild chronic pulmonary inflammation. ICA and NICA did not cause any inflammatory responses in the lungs, suggesting that ICA and NICA may be safer CAs for VFSS than Ba.Level of EvidenceNA

P53: The endothelium defender.

P53 represents the paradigm of a multitalented transcription factor, responsible for the cellular defense against a plethora of potentially harmful stimuli. It exercises the ability to strongly oppose both cancer and inflammation, partially due to the fact that both conditions are highly interrelated. Endothelium hyperpermeability is considered the hallmark of severe lung inflammation, and the cardinal feature of the lethal acute respiratory distress syndrome. An emerging body of evidence suggests a strategic role of P53 towards vascular barrier integrity. The "endothelium defender" orchestrates meticulously devised responses; to counteract toxin-induced destructions of endothelium monolayers. The present effort seeks to further our understanding on the expanding P53 universe, discussing the most recent information regarding the involvement of that molecule in the pulmonary function.

POM121 inhibits the macrophage inflammatory response by impacting NF-κB P65 nuclear accumulation

The nuclear pore membrane protein 121 (POM121) was originally thought to be a constitutive protein of the nuclear pore complex (NPC). In addition to being involved in NPC assembly, abnormal POM121 expression has been found to be associated with many diseases. In this study, we explored, in detail, the effect of POM121 on the macrophage inflammatory response and found that its expression was significantly lower in LPS-stimulated macrophages, substantially amplifying pro-inflammatory cytokine (TNF-α and IL-6) production, suggesting that POM121 exerts a potent inhibitory effect on macrophage inflammation. Consistent with this notion, greater susceptibility to LPS-induced acute lung injury (ALI) as well as more severe tissue inflammation were found in POM121fl/fl Lyzm-Cre+ mice compared to those in control mice, as evidenced by the more severe lung injury and inflammation, increased TNF-α and IL-6 production and more abundant proteins in bronchoalveolar lavage fluid (BALF). This inflammation-modulating effect of POM121 relied on its ability to repress the NF-κB signal pathway via inhibition of phosphorylated P65 (phos-P65) nuclear accumulation. In the present study, we reported that in addition to acting as a constitutive NPC component, POM121 also modulated LPS-induced macrophage inflammation via repressing nuclear P65 translocation. Our study may pave the way for regulating LPS-induced massive macrophage inflammation and providing evidence for the functional diversity of nucleoporins (Nups).

Suppression of lung inflammation by the ethanol extract of Chung-Sang and the possible role of Nrf2

BackgroundAsian traditional herbal remedies are typically a concoction of a major and several complementary herbs. While balancing out any adverse effect of the major herb, the complementary herbs could dilute the efficacy of the major herb, resulting in a suboptimal therapeutic effect of an herbal remedy. Here, we formulated Chung-Sang (CS) by collating five major herbs, which are used against inflammatory diseases, and tested whether an experimental formula composed of only major herbs is effective in suppressing inflammation without significant side effects.MethodsThe 50% ethanol extract of CS (eCS) was fingerprinted by HPLC. Cytotoxicity to RAW 264.7 cells was determined by an MTT assay and a flow cytometer. Nuclear NF-κB and Nrf2 were analyzed by western blot. Ubiquitinated Nrf2 was similarly analyzed following immunoprecipitation of Nrf2. Acute lung inflammation and sepsis were induced in C57BL/6 mice. The effects of eCS on lung disease were measured by HE staining of lung sections, a differential cell counting of bronchoalveolar lavage fluid, a myeloperoxidase (MPO) assay, a real-time qPCR, and Kaplan-Meier survival of mice.ResultseCS neither elicited cytotoxicity nor reactive oxygen species. While not suppressing NF-κB, eCS activated Nrf2, reduced the ubiquitination of Nrf2, and consequently induced the expression of Nrf2-dependent genes. In an acute lung inflammation mouse model, an intratracheal (i.t.) eCS suppressed neutrophil infiltration, the expression of inflammatory cytokine genes, and MPO activity. In a sepsis mouse model, a single i.t. eCS was sufficient to significantly decrease mouse mortality.ConclusionseCS could suppress severe lung inflammation in mice. This effect seemed to associate with eCS activating Nrf2. Our findings suggest that herbal remedies consisting of only major herbs are worth considering.

The Mouse as a Model for Pulmonary Legionella Infection.

Infection of C57BL/6 mice with wild-type Legionella pneumophila typically results in very mild disease. However, in mice where the cytosolic recognition of flagellin is impaired by mutation, L. pneumophila infection results in more severe lung inflammation that is reminiscent of Legionnaires' disease. This can be replicated in wild-type mice by using aflagellated mutants of L. pneumophila. These models greatly facilitate the investigation of L. pneumophila virulence factors and the complex pulmonary immune system that is triggered by infection. Here we describe methods for infecting C57BL/6 mice with aflagellated L. pneumophila, the quantification of bacterial load in the lungs and isolation and analysis of invading immune cells. These assays enable the identification of phagocyte subsets and can determine whether phagocytic cells act as a replicative niche for L. pneumophila replication.