Loss of endothelial CFTR drives barrier failure and edema formation in lung infection and can be targeted by CFTR potentiation.

Pneumonia is the most common cause of the acute respiratory distress syndrome (ARDS). Here, we identified loss of endothelial cystic fibrosis transmembrane conductance regulator (CFTR) as an important pathomechanism leading to lung barrier failure in pneumonia-induced ARDS. CFTR was down-regulated after Streptococcus pneumoniae infection ex vivo or in vivo in human or murine lung tissue, respectively. Analysis of isolated perfused rat lungs revealed that CFTR inhibition increased endothelial permeability in parallel with intracellular chloride ion and calcium ion concentrations ([Cl-]i and [Ca2+]i). Inhibition of the chloride ion-sensitive with-no-lysine kinase 1 (WNK1) protein with tyrphostin 47 or WNK463 replicated the effect of CFTR inhibition on endothelial permeability and endothelial [Ca2+]i, whereas WNK1 activation by temozolomide attenuated it. Endothelial [Ca2+]i transients and permeability in response to inhibition of either CFTR or WNK1 were prevented by inhibition of the cation channel transient receptor potential vanilloid 4 (TRPV4). Mice deficient in Trpv4 (Trpv4-/-) developed less lung edema and protein leak than their wild-type littermates after infection with S. pneumoniae. The CFTR potentiator ivacaftor prevented lung CFTR loss, edema, and protein leak after S. pneumoniae infection in wild-type mice. In conclusion, lung infection caused loss of CFTR that promoted lung edema formation through intracellular chloride ion accumulation, inhibition of WNK1, and subsequent disinhibition of TRPV4, resulting in endothelial calcium ion influx and vascular barrier failure. Ivacaftor prevented CFTR loss in the lungs of mice with pneumonia and may, therefore, represent a possible therapeutic strategy in people suffering from ARDS due to severe pneumonia.

Transcriptomic comparison of primary human lung cells with lung tissue samples and the human A549 lung cell line highlights cell type specific responses during infections with influenza A virus.

Influenza A virus (IAV) causes pandemics and annual epidemics of severe respiratory infections. A better understanding of the molecular regulation in tissue and cells upon IAV infection is needed to thoroughly understand pathogenesis. We analyzed IAV replication and gene expression induced by IAV strain H3N2 Panama in isolated primary human alveolar epithelial type II cells (AECIIs), the permanent A549 adenocarcinoma cell line, alveolar macrophages (AMs) and explanted human lung tissue by bulk RNA sequencing. Primary AECII exhibit in comparison to AM a broad set of strongly induced genes related to RIG-I and interferon (IFN) signaling. The response of AECII was partly mirrored in A549 cells. In human lung tissue, we observed induction of genes unlike in isolated cells. Viral RNA was used to correlate host cell gene expression changes with viral burden. While relative induction of key genes was similar, gene abundance was highest in AECII cells and AM, while weaker in the human lung (due to less IAV replication) and A549 cells (pointing to their limited suitability as a model). Correlation of host gene induction with viral burden allows a better understanding of the cell-type specific induction of pathways and a possible role of cellular crosstalk requiring intact tissue.

Initial Experience With SARS-CoV-2-Neutralizing Monoclonal Antibodies in Kidney or Combined Kidney-Pancreas Transplant Recipients.

Background: Antiviral drugs have shown little impact in patient infected with acute respiratory coronavirus 2 (SARS-CoV-2). Especially for immunocompromised persons positive for SARS-CoV-2, novel treatments are warranted. Recently, the U.S. FDA has granted an emergency use authorization (EUA) to two monoclonal antibodies (mAb) targeting the viral spike protein: bamlanivimab and casivirimab and imdevimab. As per the EUA, all SARS-CoV-2 positive organ transplant recipients can receive mAb treatment. Patients and methods: We queried our center's transplant registry to identify SARS-CoV-2 infected recipients treated with single doses of either Bamlanivimab or casivirimab/imdevimab up to May 31, 2021. We analyzed clinical outcomes, renal function and virus-specific antibodies. The co-primary endpoints were hospitalization due to COVID-19 and SARS-CoV-2 RT-PCR negativity. Results: Thirteen patients at a median interval of 55 (IQR, 26-110) months from transplant were treated: 8 with bamlanivimab and 5 with casivirimab/imdevimab. In all, 4/13 (31%) patients were hospitalized at some time, while 11/13 (85%) achieved PCR negativity. 2/4 hospitalized patients received mAb as rescue treatment. Overall mortality was 23%, with one death attributable to transplant-associated lymphoma. All six patients infected with the B 1.1.7 variant were alive at last contact. Conclusion: mAb treatment appears effective when administered early to SARS-CoV-2-infected transplant recipients.

Effectiveness of Immune Checkpoint Inhibition vs Chemotherapy in Combination With Radiation Therapy Among Patients With Non-Small Cell Lung Cancer and Brain Metastasis Undergoing Neurosurgical Resection.

Importance: Patients with brain metastases from non-small cell lung cancer (NSCLC) have regularly been excluded from prospective clinical trials that include therapy with immune checkpoint inhibitors (ICIs). Clinical data demonstrating benefit with ICIs, specifically following neurosurgical brain metastasis resection, are scarce. Objective: To evaluate and compare the association of radiation therapy with ICIs vs classic therapy involving radiation therapy and chemotherapy regarding overall survival in a cohort of patients who underwent NSCLC brain metastasis resection. Design, Setting and Participants: This single-center 1:1 propensity-matched comparative effectiveness study at the largest neurosurgical clinic in Germany included individuals who had undergone craniotomy with brain metastasis resection from January 2010 to December 2021 with histologically confirmed NSCLC. Of 1690 patients with lung cancer and brain metastasis, 480 were included in the study. Key exclusion criteria were small-cell lung cancer, lack of tumor cells by means of histopathological analysis on brain metastasis resection, and patients who underwent biopsy without tumor resection. The association of overall survival with treatment with radiation therapy and chemotherapy vs radiation therapy and ICI was evaluated. Exposures: Radiation therapy and chemotherapy vs radiation therapy and ICI following craniotomy and microsurgical brain metastasis resection. Main Outcomes and Measures: Median overall survival. Results: From the whole cohort of patients with NSCLC (N = 384), 215 (56%) were male and 169 (44%) were female. The median (IQR) age was 64 (57-72) years. The 2 cohorts of interest included 108 patients (31%) with radiation therapy and chemotherapy and 63 patients (16%) with radiation therapy and ICI following neurosurgical metastasis removal (before matching). Median (IQR) follow-up time for the total cohort was 47.9 (28.2-70.1) months with 89 patients (23%) being censored and 295 (77%) dead at the end of follow-up in December 2021. After covariate equalization using propensity score matching (62 patients per group), patients receiving radiation therapy and chemotherapy after neurosurgery had significantly lower overall survival (11.8 months; 95% CI; 9.1-15.2) compared with patients with radiation therapy and ICIs (23.0 months; 95% CI; 20.3-53.8) (P < .001). Conclusions and Relevance: Patients with NSCLC brain metastases undergoing neurosurgical resection had longer overall survival when treated with radiation therapy and ICIs following neurosurgery compared with those receiving platinum-based chemotherapy and radiation. Radiation and systemic immunotherapy should be regularly evaluated as a treatment option for these patients.

Complement activation induces excessive T cell cytotoxicity in severe COVID-19.

Severe COVID-19 is linked to both dysfunctional immune response and unrestrained immunopathology, and it remains unclear whether T cells contribute to disease pathology. Here, we combined single-cell transcriptomics and single-cell proteomics with mechanistic studies to assess pathogenic T cell functions and inducing signals. We identified highly activated CD16+ T cells with increased cytotoxic functions in severe COVID-19. CD16 expression enabled immune-complex-mediated, T cell receptor-independent degranulation and cytotoxicity not found in other diseases. CD16+ T cells from COVID-19 patients promoted microvascular endothelial cell injury and release of neutrophil and monocyte chemoattractants. CD16+ T cell clones persisted beyond acute disease maintaining their cytotoxic phenotype. Increased generation of C3a in severe COVID-19 induced activated CD16+ cytotoxic T cells. Proportions of activated CD16+ T cells and plasma levels of complement proteins upstream of C3a were associated with fatal outcome of COVID-19, supporting a pathological role of exacerbated cytotoxicity and complement activation in COVID-19.

Impact of Ventilation Modes on Bronchoscopic Chartis Assessment Outcome in Candidates for Endobronchial Valve Treatment.

BACKGROUND: Endobronchial valve therapy has proven to reduce lung hyperinflation and decrease disease burden in patients with severe lung emphysema. Exclusion of collateral ventilation (CV) of the targeted lobe by using an endobronchial assessment system (Chartis; PulmonX, Drive Redwood City, CA, USA) in combination with software-based fissure integrity analysis (FCS [fissure completeness score]) of computed tomography scans of the lung are established tools to select appropriate patients for endobronchial valve treatment. So far, there is no conclusive evidence if the ventilation mode during bronchoscopy impacts the outcome of Chartis assessments. METHODS: Patients with Chartis assessments and software-based quantification of FCS (StratX; PulmonX, Drive Redwood City, CA, USA) were enrolled in this retrospective study. During bronchoscopy, pulmonary fissure integrity was evaluated with the Chartis assessment system in each patient first under spontaneous breathing and subsequently under high-frequency (HF) jet ventilation. RESULTS: In total, 102 patients were analyzed. Four Chartis phenotypes CV positive (CV+), CV negative (CV-), low flow, and low plateau in spontaneous breathing and HF jet ventilation were identified. The frequency of each Chartis phenotype per lobe was similar in both settings. When comparing Chartis assessments in spontaneous breathing and HF jet ventilation, there was an overall good concordance rate for all analyzed fissures. In agreement, receiver operating characteristic analysis of the FCS showed an almost similar prediction for CV+ and CV- status independent of the ventilation modes. CONCLUSION: Chartis assessment in spontaneous breathing and HF jet ventilation had similar rates in detecting CV in lung emphysema. Our results suggest that both modes are equivalent for the assessment of CV.

SARS-CoV-2 infection triggers profibrotic macrophage responses and lung fibrosis.

COVID-19-induced "acute respiratory distress syndrome" (ARDS) is associated with prolonged respiratory failure and high mortality, but the mechanistic basis of lung injury remains incompletely understood. Here, we analyze pulmonary immune responses and lung pathology in two cohorts of patients with COVID-19 ARDS using functional single-cell genomics, immunohistology, and electron microscopy. We describe an accumulation of CD163-expressing monocyte-derived macrophages that acquired a profibrotic transcriptional phenotype during COVID-19 ARDS. Gene set enrichment and computational data integration revealed a significant similarity between COVID-19-associated macrophages and profibrotic macrophage populations identified in idiopathic pulmonary fibrosis. COVID-19 ARDS was associated with clinical, radiographic, histopathological, and ultrastructural hallmarks of pulmonary fibrosis. Exposure of human monocytes to SARS-CoV-2, but not influenza A virus or viral RNA analogs, was sufficient to induce a similar profibrotic phenotype in vitro. In conclusion, we demonstrate that SARS-CoV-2 triggers profibrotic macrophage responses and pronounced fibroproliferative ARDS.

Temporal omics analysis in Syrian hamsters unravel cellular effector responses to moderate COVID-19.

In COVID-19, immune responses are key in determining disease severity. However, cellular mechanisms at the onset of inflammatory lung injury in SARS-CoV-2 infection, particularly involving endothelial cells, remain ill-defined. Using Syrian hamsters as a model for moderate COVID-19, we conduct a detailed longitudinal analysis of systemic and pulmonary cellular responses, and corroborate it with datasets from COVID-19 patients. Monocyte-derived macrophages in lungs exert the earliest and strongest transcriptional response to infection, including induction of pro-inflammatory genes, while epithelial cells show weak alterations. Without evidence for productive infection, endothelial cells react, depending on cell subtypes, by strong and early expression of anti-viral, pro-inflammatory, and T cell recruiting genes. Recruitment of cytotoxic T cells as well as emergence of IgM antibodies precede viral clearance at day 5 post infection. Investigating SARS-CoV-2 infected Syrian hamsters thus identifies cell type-specific effector functions, providing detailed insights into pathomechanisms of COVID-19 and informing therapeutic strategies.

KRASG12C/TP53 co-mutations identify long-term responders to first line palliative treatment with pembrolizumab monotherapy in PD-L1 high (≥50%) lung adenocarcinoma.

BACKGROUND: Pembrolizumab is a standard of care as first line palliative therapy in PD-L1 overexpressing (≥50%) non-small cell lung cancer (NSCLC). This study aimed at the identification of KRAS and TP53-defined mutational subgroups in the PD-L1 high population to distinguish long-term responders from those with limited benefit. METHODS: In this retrospective, observational study, patients from 4 certified lung cancer centers in Berlin, Germany, having received pembrolizumab monotherapy as first line palliative treatment for lung adenocarcinoma (LuAD) from 2017 to 2018, with PD-L1 expression status and targeted NGS data available, were evaluated. RESULTS: A total of 119 patients were included. Rates for KRAS, TP53 and combined mutations were 52.1%, 47.1% and 21.9%, respectively, with no association given between KRAS and TP53 mutations (P=0.24). By trend, PD-L1 expression was higher in KRAS-positive patients (75% vs. 65%, P=0.13). Objective response rate (ORR), median progression-free survival (PFS) and overall survival (OS) in the KRASG12C group (n=32, 51.6%) were 63.3%, 19.8 months (mo.) and not estimable (NE), respectively. Results in KRASother and wild type patients were similar and by far lower (42.7%, P=0.06; 6.2 mo., P<0.001; 23.4 mo., P=0.08). TP53 mutations alone had no impact on response and survival. However, KRASG12C/TP53 co-mutations (n=12) defined a subset of long-term responders (ORR 100.0%, PFS 33.3 mo., OS NE). In contrast, patients with KRASother/TP53 mutations showed a dismal prognosis (ORR 27.3%, P=0.002; PFS 3.9 mo., P=0.001, OS 9.7 mo., P=0.02). CONCLUSIONS: A comprehensive assessment of KRAS subtypes and TP53 mutations allows a highly relevant prognostic differentiation of patients with metastatic, PD-L1 high LuAD treated upfront with pembrolizumab.

Ultra-fast proteomics with Scanning SWATH.

Accurate quantification of the proteome remains challenging for large sample series and longitudinal experiments. We report a data-independent acquisition method, Scanning SWATH, that accelerates mass spectrometric (MS) duty cycles, yielding quantitative proteomes in combination with short gradients and high-flow (800 µl min-1) chromatography. Exploiting a continuous movement of the precursor isolation window to assign precursor masses to tandem mass spectrometry (MS/MS) fragment traces, Scanning SWATH increases precursor identifications by ~70% compared to conventional data-independent acquisition (DIA) methods on 0.5-5-min chromatographic gradients. We demonstrate the application of ultra-fast proteomics in drug mode-of-action screening and plasma proteomics. Scanning SWATH proteomes capture the mode of action of fungistatic azoles and statins. Moreover, we confirm 43 and identify 11 new plasma proteome biomarkers of COVID-19 severity, advancing patient classification and biomarker discovery. Thus, our results demonstrate a substantial acceleration and increased depth in fast proteomic experiments that facilitate proteomic drug screens and clinical studies.

Pembrolizumab as First-Line Palliative Therapy in PD-L1 Overexpressing (≥ 50%) NSCLC: Real-world Results with Special Focus on PS ≥ 2, Brain Metastases, and Steroids.

INTRODUCTION: Pembrolizumab is a highly effective standard of care in PD-L1 overexpressing (≥ 50%) non-small-cell lung cancer. However, a substantial share of patients from everyday clinical practice is treated without clear evidence from clinical trials. PATIENTS AND METHODS: We performed a retrospective multicentric study including all consecutive patients from 6 certified lung cancer centers in Berlin, Germany, having received pembrolizumab as first-line palliative therapy from January 1 until December 31, 2017. Aims were to validate published clinical trials with a special focus on efficacy and outcome in patients with reduced performance status (PS), brain metastases, and steroids. RESULTS: A total of 153 patients were included (median age 69 years, 58% men, 69% adenocarcinoma). Rates for PS ≥ 2, brain metastases, and steroids were 24.8%, 20.9%, and 24.2%, respectively. Median objective response rate, progression-free and overall survival were 48.5%, 8.2 and 22.0 months for all patients and 52.4%, 8.8 and 29.2 months in patients fulfilling the inclusion criteria for the KEYNOTE-024 trial. Patients with a comorbidity-defined PS ≥ 2, symptomatic brain metastases requiring upfront radiotherapy, or baseline steroids had significantly reduced survival. In contrast, durable responses occurred with a tumor-related PS ≥ 2 or asymptomatic brain metastases. Grade 3/4 and 5 immune-related adverse events affected 13.7% and 2.0% of patients. CONCLUSION: Real-world and clinical trial efficacy with upfront pembrolizumab correspond well. Pembrolizumab may sufficiently control asymptomatic brain metastases and may improve a cancer-related reduced PS. However, the frail share of patients with a comorbidity-defined PS ≥ 2, symptomatic brain metastases, or baseline steroids derives no relevant benefit.

Clonal expansion of CD4+CD8+ T cells in an adult patient with Mycoplasma pneumoniae-associated Erythema multiforme majus.

BACKGROUND: Erythema multiforme (EM) is an acute, immune-mediated mucocutaneous disease, most often preceded by herpes simplex virus (HSV) infection or reactivation. Mycoplasma pneumoniae (Mp) is considered the second major trigger of EM and is often associated with an atypical and more severe presentation of disease, characterized by prominent mucosal involvement. However, contrary to HSV-associated Erythema multiforme (HAEM), immunological mechanisms of Mp-associated EM remain unclear. CASE PRESENTATION: We present the case of a 50-year-old male patient presenting with community-acquired pneumonia (CAP) and erythema multiforme majus (EMM). Acute Mp infection was diagnosed by seroconversion, with no evidence of HSV infection as a cause of EMM. We performed immune phenotyping of blister fluid (BF) and peripheral blood (PB) T cells and detected a clonally expanded TCRVß2+ T cell population that was double positive for CD4 and CD8, and expressed the cytotoxic markers granulysin and perforin. This CD4+CD8+ population comprised up to 50.7% of BF T cells and 24.9% of PB T cells. Two years prior to the onset of disease, the frequency of PB CD4+CD8+T cells had been within normal range and it gradually returned to baseline levels with the resolution of symptoms, suggesting an involvement of this population in EMM disease pathophysiology. CONCLUSIONS: This report is the first to provide a phenotypic description of lesional T cells in Mp-associated EMM. Characterizing the local immune response might help to address pathophysiological questions and warrants further systematic research.

Reversion of Pneumolysin-Induced Executioner Caspase Activation Redirects Cells to Survival.

Apoptosis is an indispensable mechanism for eliminating infected cells and activation of executioner caspases is considered to be a point of no return. Streptococcus pneumoniae, the most common bacterial pathogen causing community-acquired pneumonia, induces apoptosis via its pore-forming toxin pneumolysin, leading to rapid influxes of mitochondrial calcium [Ca2+]m as well as fragmentation, and loss of motility and membrane potential, which is accompanied by caspase-3/7 activation. Using machine-learning and quantitative live-cell microscopy, we identified a significant number of alveolar epithelial cells surviving such executioner caspase activation after pneumolysin attack. Precise single-cell analysis revealed the [Ca2+]m amplitude and efflux rate as decisive parameters for survival and death, which was verified by pharmacological inhibition of [Ca2+]m efflux shifting the surviving cells towards the dying fraction. Taken together, we identified the regulation of [Ca2+]m as critical for controlling the cellular fate under pneumolysin attack, which might be useful for therapeutic intervention during pneumococcal infection.

Dynamics of cytokines, immune cell counts and disease severity in patients with community-acquired pneumonia - Unravelling potential causal relationships.

BACKGROUND: Community acquired pneumonia (CAP) is a severe and often rapidly deteriorating disease. To better understand its dynamics and potential causal relationships, we analyzed time series data of cytokines, blood and clinical parameters in hospitalized CAP patients. METHODS: Time series data of 10 circulating cytokines, blood counts and clinical parameters were related to baseline characteristics of 403 CAP patients using univariate mixed models. Bivariate mixed models were applied to analyze correlations between the time series. To identify potential causal relationships, we inferred cross-lagged relationships between pairs of parameters using latent curve models with structured residuals. RESULTS: IL-6 levels decreased faster over time in younger patients (Padj = 0.06). IL-8, VCAM-1, and IL-6 correlated strongly with disease severity as assessed by the sequential organ failure assessment (SOFA) score (r = 0.49, 0.48, 0.46, respectively; all Padj < 0.001). IL-6 and bilirubin correlated with respect to their mean levels and slopes over time (r = 0.36 and r = 0.46, respectively; Padj < 0.001). A number of potential causal relationships were identified, e.g., a negative effect of ICAM-1 on MCP-1, or a positive effect of the level of creatinine on the subsequent VCAM-1 concentration (P < 0.001). CONCLUSIONS: These results suggest that IL-6 trajectories of CAP patients are associated with age and run parallel to bilirubin levels. The time series analysis also unraveled directed, potentially causal relationships between cytokines, blood parameters and clinical outcomes. This will facilitate the development of mechanistic models of CAP, and with it, improvements in treatment or surveillance strategies for this disease. TRIAL REGISTRATION: clinicaltrials.gov NCT02782013, May 25, 2016, retrospectively registered.

Pemetrexed-Based Chemotherapy Is Inferior to Pemetrexed-Free Regimens in Thyroid Transcription Factor 1 (TTF-1)-Negative, EGFR/ALK-Negative Lung Adenocarcinoma: A Propensity Score Matched Pairs Analysis.

INTRODUCTION: Thyroid transcription factor 1 (TTF-1) is a prognostic biomarker in lung adenocarcinoma; however, TTF-1-positive patients also display more favorable factors like actionable target mutations. In contrast, TTF-1-negative cancer is a poorly described entity. We performed a retrospective study to characterize a TTF-1-negative phenotype and to evaluate outcome depending on the chemotherapy regimen applied in the EGFR/ALK-negative population. PATIENTS AND METHODS: Phenotypic traits were analyzed in 741 patients with evaluable TTF-1 expression status, among them 529 patients with platinum-based first-line chemotherapy, with disease diagnosed between 2009 and 2016 at a tertiary referral university hospital. The influence of TTF-1 and several cofactors on progression-free survival and overall survival (OS) were analyzed using a 1:1 propensity score matching model, depending on the platinum doublet chemotherapy's incorporating pemetrexed or not, with subsequent Cox regression. RESULTS: TTF-1 negativity implied a distinct cancer phenotype with the predominance of male sex, worse Eastern Cooperative Oncology Group performance status, greater metastatic burden at primary diagnosis, and more adrenal gland metastases. These patients had improved progression-free survival (hazard ratio, 0.42; P = .001) and OS (hazard ratio, 0.40; P < .001) when gemcitabine-, taxane-, or vinorelbine-based regimens were provided instead of pemetrexed. None of the regimens was superior in TTF-1-positive patients with regard to OS. Overall, TTF-1 expression was strongly prognostic with a substantial increase in progression-free survival (hazard ratio, 0.54; P < .001) and OS (hazard ratio, 0.53; P < .001). CONCLUSION: TTF-1 negativity is associated with a distinct cancer phenotype. Incorporation of this biomarker may be helpful when choosing an appropriate therapy regimen.

COVID-19 severity correlates with airway epithelium-immune cell interactions identified by single-cell analysis.

To investigate the immune response and mechanisms associated with severe coronavirus disease 2019 (COVID-19), we performed single-cell RNA sequencing on nasopharyngeal and bronchial samples from 19 clinically well-characterized patients with moderate or critical disease and from five healthy controls. We identified airway epithelial cell types and states vulnerable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In patients with COVID-19, epithelial cells showed an average three-fold increase in expression of the SARS-CoV-2 entry receptor ACE2, which correlated with interferon signals by immune cells. Compared to moderate cases, critical cases exhibited stronger interactions between epithelial and immune cells, as indicated by ligand-receptor expression profiles, and activated immune cells, including inflammatory macrophages expressing CCL2, CCL3, CCL20, CXCL1, CXCL3, CXCL10, IL8, IL1B and TNF. The transcriptional differences in critical cases compared to moderate cases likely contribute to clinical observations of heightened inflammatory tissue damage, lung injury and respiratory failure. Our data suggest that pharmacologic inhibition of the CCR1 and/or CCR5 pathways might suppress immune hyperactivation in critical COVID-19.

Indwelling pleural catheters for non-malignant pleural effusions: report on a single centre's 10 years of experience.

BACKGROUND: Recurrent pleural effusion is a common cause of dyspnoea, cough and chest pain during the course of infectious pleurisy and non-malignant diseases like congestive heart failure (CHF) or liver cirrhosis with hepatic hydrothorax (HH). With regard to the chronic character of the underlying diseases, indwelling pleural catheters (IPC) are increasingly used, not only assuring immediate symptom relief but also potentially leading to pleurodesis without sclerosing agents. PATIENTS AND METHODS: In this single-centre retrospective observational study, patient characteristics, procedural variables and outcome in patients with IPC in non-malignant pleural effusion (NMPE) were evaluated and prognostic factors for pleurodesis were identified. RESULTS: From 2006 to 2017, 54 patients received 62 IPC, of whom 48.4% with CHF and 43.5% with HH. The median length of insertion was 1.5 months (IQR 0.6-2.9 months), the median survival time after insertion 3.2 months (IQR 1.1-16.0). An adequate symptom relief was achieved in 93.2% with no need for subsequent interventions. In patients surviving ≥30 days after IPC insertion, pleurodesis was observed in 45.9%, being associated to age (<55 years, p=0.02), the primary diagnosis (p=0.03) and interventions for the underlying disease (p<0.001). Complications occurred in 24.2% of all procedures (n=15), the majority concerning mechanical obstructions (n=10) and infections (n=4). Patients with HH had an excess risk for complications (37.3%). CONCLUSION: Efficacy in symptom relief and a generally manageable safety profile recommend IPC as a first-line treatment option in NMPE, where disease-specific treatments are exhausted. Caution is warranted in patients with HH due to an excess risk for complications.

Association of proteome and metabolome signatures with severity in patients with community-acquired pneumonia.

A combined OMICS screening approach of human plasma and serum was used to characterize protein and metabolome signatures displaying association to severity of Community-acquired pneumonia (CAP). 240 serum and BD P100 EDTA plasma samples from patients diagnosed with CAP, collected during the day of enrolment to the hospital, were analyzed by a metabolomic and proteomic approach, respectively. Disease severity of CAP patients was stratified using the Sequential Organ Failure Assessment (SOFA) score. Quantitative proteome and metabolome data, derived by LC-MS/MS, were associated to SOFA and specific parameters of SOFA using linear regression models adjusted for age, BMI, sex, smoking and technical variables. Both proteome and metabolome profiling revealed remarkable strong changes in plasma and serum composition in relation to severity of CAP. Proteins and metabolites displaying SOFA associated levels are involved in immune response, particularly in processes of lipid metabolism. Proteins, which show an association to SOFA score, are involved in acute phase response, coagulation, complement activation and inflammation. Many of these metabolites and proteins displayed not only associations to SOFA, but also to parameters of SOFA score, which likely reflect the strong influence of lung-, liver-, kidney- and heart-dysfunction on the metabolome and proteome patterns. SIGNIFICANCE: Community-acquired pneumonia is the most frequent infection disease with high morbidity and mortality. So far, only few studies focused on the identification of proteins or metabolites associated to severity of CAP, often based on smaller sample sets. A screening for new diagnostic markers requires extensive sample collections in combination with high quality clinical data. To characterize the proteomic and metabolomics pattern associated to severity of CAP we performed a combined metabolomics and proteomic approach of serum and plasma sample from a multi-center clinical study focused on patients with CAP, requiring hospitalization. The results of this association study of omics data to the SOFA score enable not only an interpretation of changes in molecular patterns with severity of CAP but also an assignment of altered molecules to dysfunctions of respiratory, renal, coagulation, cardiovascular systems as well as liver.

Induction of Krüppel-Like Factor 4 Mediates Polymorphonuclear Neutrophil Activation in Streptococcus pneumoniae Infection.

The recruitment and activation of polymorphonuclear neutrophils (PMNs) are of central importance for the elimination of pathogens in bacterial infections. We investigated the Streptococcus pneumoniae-dependent induction of the transcription factor Krüppel-like factor (KLF) 4 in PMNs as a potential regulator of PMN activation. We found that KLF4 expression is induced in human blood-derived PMNs in a time- and dose-dependent manner by wild-type S. pneumoniae and capsule knockout mutants. Unencapsulated knockout mutants induced stronger KLF4 expression than encapsulated wild types. The presence of autolysin LytA-competent (thus viable) pneumococci and LytA-mediated bacterial autolysis were required for KLF4 induction in human and murine PMNs. LyzMcre-mediated knockdown of KLF4 in murine blood-derived PMNs revealed that KLF4 influences pneumococci killing and increases the release of the proinflammatory cytokines tumor necrosis factor α and keratinocyte chemoattractant and decreases the release of the anti-inflammatory cytokine interleukin-10. Thus, S. pneumoniae induces KLF4 expression in PMNs, which contributes to PMN activation in S. pneumoniae infection.