Search

Pneumothorax and persistent air leak (PAL) are documented complications of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. Patients that fall in this category are often poor candidates for invasive thoracic surgical intervention. Endobronchial valves offer an effective and less invasive treatment option and can successfully treat PAL and support the weaning of patients with SARS-CoV-2 pneumonia off ventilation.

A defining pathological feature of human lung fibrosis is localized tissue heterogeneity, which challenges the interpretation of transcriptomic studies that typically lose spatial information. Here we investigate spatial gene expression in diagnostic tissue using digital profiling technology. We identify distinct, region-specific gene expression signatures as well as shared gene signatures. By integration with single-cell data, we spatially map the cellular composition within and distant from the fibrotic niche, demonstrating discrete changes in homeostatic and pathologic cell populations even in morphologically preserved lung, while through ligand-receptor analysis, we investigate cellular cross-talk within the fibrotic niche. We confirm findings through bioinformatic, tissue, and in vitro analyses, identifying that loss of NFKB inhibitor zeta in alveolar epithelial cells dysregulates the TGFβ/IL-6 signaling axis, which may impair homeostatic responses to environmental stress. Thus, spatially resolved deconvolution advances understanding of cell composition and microenvironment in human lung fibrogenesis.

Objectives To demonstrate the feasibility and preliminary outcomes of a novel hybrid technique combining percutaneous microwave ablation and wire-assisted wedge resection for patients with multiple pulmonary metastases using intraoperative imaging. Methods We describe our technique and present a retrospective case series of 4 patients undergoing iCART at our institution between August 2018 and January 2020. Procedures were performed in a hybrid operating suite using the ARTIS Pheno cone beam computerized tomography scanner (Siemens Healthineers, Erlangen, German). Patient information included past history of malignancy as well as lesion size, depth, location, and histology result. Surgical complications and length of stay were also recorded. Results Five procedures were performed on 4 patients during the study period. One patient underwent bilateral procedures 4 weeks apart. All patients underwent at least 1 ablation and 1 wedge resection during the combined procedure. Patient ages ranged from 40 to 66 years and the majority (75%) were men. All had a past history of cancer. Lesions were treated in every lobe. Size and depth ranged from 6 to 24 mm and 21 to 33 mm, respectively, for ablated nodules and 5 to 27 mm and 0 to 22 mm, respectively, for the wedge resected nodules. Three procedures were completed uniportal and operative time ranged from 51 to 210 minutes. All cases sustained, Graphical abstract

To demonstrate the safety and feasibility of advanced nurse practitioner-led (ANP-led) outpatient follow-up after discharge with ambulatory chest drains for prolonged air leak and excessive fluid drainage.Patients discharged with ambulatory chest drains between January 2017 and December 2019 were retrospectively reviewed. Discharge criteria included air leak 200 ml/min or fluid drainage 100 ml/24 h on a digital drain. Patients were reviewed weekly in the clinic by ANPs, a highly skilled cohort of nurses with physician support available. Outcomes included length of stay, duration of air or fluid leak and complications.Two-hundred patients were included, amounting to 368 clinic episodes. The median age was 68 ± 13 years and 119 (60%) were male. 112 (56%) patients underwent anatomical lung resection (total anatomical lung resections during the study period = 917) equating to a discharge with ambulatory chest drain rate of 12.2% in this group. The median length of stay was 6 ± 3 days and 176 (88%) patients were discharged with air leak versus 24 (12%) with excessive fluid drainage. The median time to drain removal was 12 ± 11 days. Complications occurred in 16 patients (8%) and 12 (6%) required readmission. An estimated 2075 inpatient days were saved over the study period equating to an annual cost saving of £123,167 (US$149,032) per annum.Patients with air leak or excessive fluid drainage can safely be discharged with ambulatory chest drains, allowing them to return to their familiar home environment safely and quickly. ANP-led clinics are a robust and cost-effective follow-up strategy and are associated with a low complication rate.

Extracellular matrix (ECM) stiffening with downstream activation of mechanosensitive pathways is strongly implicated in fibrosis. We previously reported that altered collagen nanoarchitecture is a key determinant of pathogenetic ECM structure-function in human fibrosis (Jones et al., 2018). Here, through human tissue, bioinformatic and ex vivo studies we provide evidence that hypoxia-inducible factor (HIF) pathway activation is a critical pathway for this process regardless of the oxygen status (pseudohypoxia). Whilst TGFβ increased the rate of fibrillar collagen synthesis, HIF pathway activation was required to dysregulate post-translational modification of fibrillar collagen, promoting pyridinoline cross-linking, altering collagen nanostructure, and increasing tissue stiffness. In vitro, knockdown of Factor Inhibiting HIF (FIH), which modulates HIF activity, or oxidative stress caused pseudohypoxic HIF activation in the normal fibroblasts. By contrast, endogenous FIH activity was reduced in fibroblasts from patients with lung fibrosis in association with significantly increased normoxic HIF pathway activation. In human lung fibrosis tissue, HIF-mediated signalling was increased at sites of active fibrogenesis whilst subpopulations of human lung fibrosis mesenchymal cells had increases in both HIF and oxidative stress scores. Our data demonstrate that oxidative stress can drive pseudohypoxic HIF pathway activation which is a critical regulator of pathogenetic collagen structure-function in fibrosis.

Clarke et al. interrogate human TRM cells from cancer and nonmalignant tissue. These analyses highlight that PD-1 expression in tumor-infiltrating TRM cells was positively correlated with features suggestive of active proliferation and superior functionality rather than dysfunction., High numbers of tissue-resident memory T (TRM) cells are associated with better clinical outcomes in cancer patients. However, the molecular characteristics that drive their efficient immune response to tumors are poorly understood. Here, single-cell and bulk transcriptomic analysis of TRM and non-TRM cells present in tumor and normal lung tissue from patients with lung cancer revealed that PD-1–expressing TRM cells in tumors were clonally expanded and enriched for transcripts linked to cell proliferation and cytotoxicity when compared with PD-1–expressing non-TRM cells. This feature was more prominent in the TRM cell subset coexpressing PD-1 and TIM-3, and it was validated by functional assays ex vivo and also reflected in their chromatin accessibility profile. This PD-1+TIM-3+ TRM cell subset was enriched in responders to PD-1 inhibitors and in tumors with a greater magnitude of CTL responses. These data highlight that not all CTLs expressing PD-1 are dysfunctional; on the contrary, TRM cells with PD-1 expression were enriched for features suggestive of superior functionality., Graphical Abstract

Micro-computed tomography (µCT) provides non-destructive three-dimensional (3D) imaging of soft tissue microstructures. Specific features in µCT images can be identified using correlated two-dimensional (2D) histology images allowing manual segmentation. However, this is very time-consuming and requires specialist knowledge of the tissue and imaging modalities involved. Using a custom-designed µCT system optimized for imaging unstained formalin-fixed paraffin-embedded soft tissues, we imaged human lung tissue at isotropic voxel sizes less than 10 µm. Tissue sections were stained with haematoxylin and eosin or cytokeratin 18 in columnar airway epithelial cells using immunofluorescence (IF), as an exemplar of this workflow. Novel utilization of tissue autofluorescence allowed automatic alignment of 2D microscopy images to the 3D µCT data using scripted co-registration and automated image warping algorithms. Warped IF images, which were accurately aligned with the µCT datasets, allowed 3D segmentation of immunoreactive tissue microstructures in the human lung. Blood vessels were segmented semi-automatically using the co-registered µCT datasets. Correlating 2D IF and 3D µCT data enables accurate identification, localization and segmentation of features in fixed soft lung tissue. Our novel correlative imaging workflow provides faster and more automated 3D segmentation of µCT datasets. This is applicable to the huge range of formalin-fixed paraffin-embedded tissues held in biobanks and archives.

Extracellular matrix (ECM) stiffening with downstream activation of mechanosensitive pathways is strongly implicated in fibrosis. We previously reported that altered collagen nanoarchitecture is a key determinant of pathogenetic ECM structure-function in human fibrosis (Jones et al., 2018). Here, through human tissue, bioinformatic and ex vivo studies we show that hypoxia-inducible factor (HIF) pathway activation is a critical pathway for this process regardless of oxygen status (pseudohypoxia). Whilst TGFβ increased rate of fibrillar collagen synthesis, HIF pathway activation was required to dysregulate post-translational modification of fibrillar collagen, promoting ‘bone-type’ cross-linking, altering collagen nanostructure, and increasing tissue stiffness. In vitro, knock down of Factor Inhibiting HIF (FIH) or oxidative stress caused pseudohypoxic HIF activation in normal fibroblasts. In contrast, endogenous FIH activity was reduced in fibroblasts from patients with lung fibrosis in association with significantly increased normoxic HIF pathway activation. In human lung fibrosis tissue, HIF mediated signalling was increased at sites of active fibrogenesis whilst subpopulations of IPF lung mesenchymal cells had increases in both HIF and oxidative stress scores. Our data demonstrate that oxidative stress can drive pseudohypoxic HIF pathway activation which is a critical regulator of pathogenetic collagen structure-function in fibrosis.

IntroductionGabapentin is an antiepileptic drug currently licensed to treat epilepsy and neuropathic pain but has been used off-label to treat acute postoperative pain. The GAP study will compare the effectiveness, cost-effectiveness and safety of gabapentin as an adjunct to standard multimodal analgesia versus placebo for the management of pain after major surgery.Methods and analysisThe GAP study is a multicentre, double-blind, randomised controlled trial in patients aged 18 years and over, undergoing different types of major surgery (cardiac, thoracic or abdominal). Patients will be randomised in a 1:1 ratio to receive either gabapentin (600 mg just before surgery and 600 mg/day for 2 days after surgery) or placebo in addition to usual pain management for each type of surgery. Patients will be followed up daily until hospital discharge and then at 4 weeks and 4 months after surgery. The primary outcome is length of hospital stay following surgery. Secondary outcomes include pain, total opioid use, adverse health events, health related quality of life and costs.Ethics and disseminationThis study has been approved by the Research Ethics Committee . Findings will be shared with participating hospitals and disseminated to the academic community through peer-reviewed publications and presentation at national and international meetings. Patients will be informed of the results through patient organisations and participant newsletters.Trial registration numberISRCTN63614165.

Idiopathic pulmonary fibrosis (IPF) is the prototypic progressive fibrotic lung disease with a median survival of 2 to 4 years. Injury to and/or dysfunction of the alveolar epithelium is strongly implicated in IPF disease initiation, but the factors that determine whether fibrosis progresses rather than normal tissue repair occurs remain poorly understood. We previously demonstrated that zinc finger E-box-binding homeobox 1-mediated epithelial-mesenchymal transition in human alveolar epithelial type II (ATII) cells augments transforming growth factor-β-induced profibrogenic responses in underlying lung fibroblasts via paracrine signaling. Here, we investigated bidirectional epithelial-mesenchymal crosstalk and its potential to drive fibrosis progression. RNA-Seq of lung fibroblasts exposed to conditioned media from ATII cells undergoing RAS-induced epithelial-mesenchymal transition identified many differentially expressed genes including those involved in cell migration and extracellular matrix regulation. We confirmed that paracrine signaling between RAS-activated ATII cells and fibroblasts augmented fibroblast recruitment and demonstrated that this involved a zinc finger E-box-binding homeobox 1-tissue plasminogen activator axis. In a reciprocal fashion, paracrine signaling from transforming growth factor-β-activated lung fibroblasts or IPF fibroblasts induced RAS activation in ATII cells, at least partially through the secreted protein acidic and rich in cysteine, which may signal via the epithelial growth factor receptor via epithelial growth factor-like repeats. Together, these data identify that aberrant bidirectional epithelial-mesenchymal crosstalk in IPF drives a chronic feedback loop that maintains a wound-healing phenotype and provides self-sustaining profibrotic signals.

Background: Altered collagen architecture with increased “bone-type” pyridinoline collagen cross-linking, rather than collagen quantity, is a key determinant of abnormal tissue structure-function in Idiopathic Pulmonary Fibrosis (IPF). We recently identified that hypoxia inducible factor (HIF) pathway activation promotes induction of the bone-type collagen cross-linking enzymes lysyl hydroxylase 2 and lysyl oxidase-like 2, yet the consequences of this on collagen structure-function in lung fibrosis remain unknown. Methods: Using a long term 3D in vitro model of the fibroblastic focus we cultured primary lung fibroblasts from IPF donors without or with the HIF-stabilising compound IOX2. Hydroxyproline and mature pyridinium cross-links were measured by colorimetric assays, and collagen ultrastructure assessed by electron microscopy (EM). The biomechanical effects of HIF stabilisation were investigated by parallel plate compression testing. Results: IOX2 stabilised HIF within the 3D fibroblastic focus model, promoting HIF pathway activation to disproportionately induce collagen-modifying enzymes relative to collagen fibril synthesis. After 6 weeks of culture, mature pyridinium cross-links were significantly increased by IOX2 to levels we have previously observed in IPF tissue. Ultrastructural analysis of the collagen fibrils with EM identified that IOX2 significantly reduced fibril diameter to sizes comparable with collagen fibrils enzymatically extracted from IPF tissue. IOX2 induced a greater than 3-fold increase in tissue stiffness. Conclusions: HIF pathway activation is a core regulator of bone-type collagen fibrillogenesis and altered structure-function in lung fibrosis.

Benign tracheal tumours have an incidence of 1 in 1,000,000, of which leiomyomas represent only 1%. We report a case of tracheal leiomyoma masquerading as asthma for over 20 years. A 48-year-old man presented aged 26 years with asthma symptoms unresponsive to treatments and an obstructive spirometry pattern. Symptoms were not particularly troubling but suddenly exacerbated 22 years later. Flow-volume studies were consistent with upper airway obstruction. Computed tomography chest revealed a 2.3 cm mass arising from the posterior aspect of the trachea 2 cm above the carina. Bronchoscopic resection was performed using a Nd:YAG laser. Histology confirmed leiomyoma. Follow-up after 6 weeks revealed complete resolution of symptoms with normal spirometry. Tracheal masses should be considered in any patient with atypical asthma. A flow-volume loop may provide a clue to diagnosis and bronchoscopic laser resection is a minimally invasive treatment option.

BackgroundThe role of tumor-associated macrophages (TAMs) in determining the outcome between the antitumor effects of the adaptive immune system and the tumor’s anti-immunity stratagems, is controversial. Macrophages modulate their activities and phenotypes by integration of signals in the tumor microenvironment. Depending on how macrophages are activated, they may adopt so-called M1-like, antitumor or M2-like, protumor profiles. In many solid tumors, a dominance of M2-like macrophages is associated with poor outcomes but in some tumor types, strong M1-like profiles are linked to better outcomes. We aimed to investigate the interrelationship of these TAM populations to establish how they modulate the efficacy of the adaptive immune system in early lung cancer.MethodsMacrophages from matched lung (non-tumor-associated macrophages (NTAMs)) and tumor samples (TAMs) from resected lung cancers were assessed by bulk and single-cell transcriptomic analysis. Protein expression of genes characteristic of M1-like (chemokine (C-X-C motif) ligand 9) or M2-like (matrix metallopeptidase 12) functions was confirmed by confocal microscopy. Immunohistochemistry related the distribution of TAM transcriptomic signatures to density of CD8+tissue-resident memory T cells (TRM) in tumors and survival data from an independent cohort of 393 patients with lung cancer.ResultsTAMs have significantly different transcriptomic profiles from NTAMs with >1000 differentially expressed genes. TAMs displayed a strong M2-like signature with no significant variation between patients. However, single-cell RNA-sequencing supported by immuno-stained cells revealed that additionally, in 25% of patients the M2-like TAMs also co-expressed a strong/hot M1-like signature (M1hot). Importantly, there was a strong association between the density of M1hotTAMs and TRMcells in tumors that was in turn linked to better survival. Our data suggest a mechanism by which M1hotTAMs may recruit TRMcells via CXCL9 expression and sustain them by making available more of the essential fatty acids on which TRMdepend.ConclusionsWe showed that in early lung cancer, expression of M1-like and M2-like gene signatures are not mutually exclusive since the same TAMs can simultaneously display both gene-expression profiles. The presence of M1hotTAMs was associated with a strong TRMtumor-infiltrate and better outcomes. Thus, therapeutic approaches to re-program TAMs to an M1hotphenotype are likely to augment the adaptive antitumor responses.

Sternal osteomyelitis is a morbid and challenging condition, which can rarely occur after trauma, with no established consensus over best therapeutic options. In this case, a 47-year-old man with history of intravenous drug use presented 11 weeks after a minor blunt chest trauma with a severe necrotizing osteomyelitis involving sternum, muscles, fascia and subcutaneous tissue and positive blood cultures for Methicillin Sensitive Staphylococcus aureus. Alongside tailored antibiotic therapy, extensive surgical debridement was performed, leaving a full thickness 3 × 4 cm sternal defect and a large skin defect. After 4 weeks of antibiotics and Vacuum-Assisted-Closure pump, a novel reconstruction technique was utilized, with full collaborations of thoracic surgeons, orthopaedic surgeons and plastic surgeons. An autologous tricortical iliac crest bone graft was harvested and shaped to fit the full-thickness sternal defect, while two titanium sigmoid-shaped clavicle plates were used for internal fixation of the autograft. The large skin defect was covered with a pedicled myocutaneous latissimus dorsi flap. Integrity and stability of the chest wall was fully restored, and infection was completely eradicated. No complications occurred and the patient was well at the 18 months follow-up. To the best of our knowledge, this is the first report on autologous iliac crest bone graft in the treatment of sternal osteomyelitis. In this case, it proved to be a viable therapeutic option, providing good long-term clinical and cosmetic results.

Background The role of tumor-associated macrophages (TAMs) in determining the outcome between the antitumor effects of the adaptive immune system and the tumor’s anti-immunity stratagems, is controversial. Macrophages modulate their activities and phenotypes by integration of signals in the tumor microenvironment. Depending on how macrophages are activated, they may adopt so-called M1-like, antitumor or M2-like, protumor profiles. In many solid tumors, a dominance of M2-like macrophages is associated with poor outcomes but in some tumor types, strong M1-like profiles are linked to better outcomes. We aimed to investigate the interrelationship of these TAM populations to establish how they modulate the efficacy of the adaptive immune system in early lung cancer. Methods Macrophages from matched lung (non-tumor-associated macrophages (NTAMs)) and tumor samples (TAMs) from resected lung cancers were assessed by bulk and single-cell transcriptomic analysis. Protein expression of genes characteristic of M1-like (chemokine (C-X-C motif) ligand 9) or M2-like (matrix metallopeptidase 12) functions was confirmed by confocal microscopy. Immunohistochemistry related the distribution of TAM transcriptomic signatures to density of CD8+ tissue-resident memory T cells (TRM) in tumors and survival data from an independent cohort of 393 patients with lung cancer. Results TAMs have significantly different transcriptomic profiles from NTAMs with >1000 differentially expressed genes. TAMs displayed a strong M2-like signature with no significant variation between patients. However, single-cell RNA-sequencing supported by immuno-stained cells revealed that additionally, in 25% of patients the M2-like TAMs also co-expressed a strong/hot M1-like signature (M1hot). Importantly, there was a strong association between the density of M1hot TAMs and TRM cells in tumors that was in turn linked to better survival. Our data suggest a mechanism by which M1hot TAMs may recruit TRM cells via CXCL9 expression and sustain them by making available more of the essential fatty acids on which TRM depend. Conclusions We showed that in early lung cancer, expression of M1-like and M2-like gene signatures are not mutually exclusive since the same TAMs can simultaneously display both gene-expression profiles. The presence of M1hot TAMs was associated with a strong TRM tumor-infiltrate and better outcomes. Thus, therapeutic approaches to re-program TAMs to an M1hot phenotype are likely to augment the adaptive antitumor responses.

To determine the nature of CD4+ T cells that provide ‘help’ for generating robust anti-tumor CD8+ cytotoxic T cell (CTL) responses, we profiled the transcriptomes of patient-matched CD4+ and CD8+ T cells present in the tumor micro-environment (TME) and analyzed them jointly using integrated weighted gene correlation network analysis. We found the follicular helper T cell (TFH) program in CD4+ T cells was strongly associated with proliferation and tissue-residency in CD8+ CTLs. Single-cell analysis demonstrated the presence of TFH-like cells and features linked to cytotoxic function and their provision of CD8+ T cell ‘help’. Tumor-infiltrating TFH-like cells expressed PD-1 and were enriched in tumors following checkpoint blockade, suggesting that they may respond to anti-PD-1 therapy. Adoptive transfer or induction of TFH cells in mouse models resulted in augmented CD8+ CTL responses and impairment of tumor growth, indicating an important role of TFH-like CD4+ T cells in anti-tumor immunity.

Idiopathic pulmonary fibrosis (IPF) is a chronic scarring disease in which aging, environmental exposure(s) and genetic susceptibility have been implicated in disease pathogenesis, however, the causes and mechanisms of the progressive fibrotic cascade are still poorly understood. As epithelial–mesenchymal interactions are essential for normal wound healing, through human 2D and 3D in vitro studies, we tested the hypothesis that IPF fibroblasts (IPFFs) dysregulate alveolar epithelial homeostasis. Conditioned media from IPFFs exaggerated the wound-healing response of primary human Type II alveolar epithelial cells (AECs). Furthermore, AECs co-cultured with IPFFs exhibited irregular epithelialization compared with those co-cultured with control fibroblasts (NHLFs) or AECs alone, suggesting that epithelial homeostasis is dysregulated in IPF as a consequence of the abnormal secretory phenotype of IPFFs. Secretome analysis of IPFF conditioned media and functional studies identified the matricellular protein, SPARC, as a key mediator in the epithelial–mesenchymal paracrine signaling, with increased secretion of SPARC by IPFFs promoting persistent activation of alveolar epithelium via an integrin/focal adhesion/cellular-junction axis resulting in disruption of epithelial barrier integrity and increased macromolecular permeability. These findings suggest that in IPF fibroblast paracrine signaling promotes persistent alveolar epithelial activation, so preventing normal epithelial repair responses and restoration of tissue homeostasis. Furthermore, they identify SPARC-mediated paracrine signaling as a potential therapeutic target to promote the restoration of lung epithelial homoestasis in IPF patients.

Immune checkpoint blockade (ICB) has shown remarkable clinical success in boosting anti-tumor immunity. However, the breadth of its cellular targets and specific mode of action remain elusive. We find that T follicular regulatory (TFR) cells are present in high numbers in multiple tumors, inhibit anti-tumor immunity and are responsive to ICB. TCR-seq data, trajectory analyses and adoptive transfer studies indicate intratumoral TREG to TFR cell conversion. When compared to TREG cells, TFR cells exhibited enhanced suppressive capacity. In syngeneic tumor models, anti-PD-1 treatment increased the number of tumor-infiltrating TFR cells. Conditional knockout of TFR cells or depletion of TFR cells with anti-CTLA-4 antibody prior to anti-PD-1 treatment, improved tumor control in mice. Notably, in a cohort of melanoma patients, treatment with anti-CTLA-4 followed by anti-PD-1 at progression was associated with better long-term survival outcomes than anti-PD-1 or anti-CTLA-4 monotherapy, anti-PD-1 followed by anti CTLA-4 at progression or concomitant combination therapy.

Objective The aim of the study was to report the safety and efficacy of video-assisted thoracoscopic (VATS) plication of the diaphragm at our institution between 2006 and 2016. Methods Adult patients selected on etiology and combination of investigations including plain chest x-ray, computed tomography of chest and abdomen, lung functions in supine and sitting positions, radiological/ultrasonic screening for diaphragmatic movement, and phrenic nerve conduction studies. We incorporated a triportal VATS and Endostitch device for plication, using CO2 insufflation to maximum 12 mm Hg. Bilateral simultaneous plication and high-risk patients were electively admitted to intensive therapy unit postoperatively. Results Thirty-five patients (24 males) had their diaphragm plicated. The mean age was 56.6 years (range = 23–76 years). The mean body mass index was 32.1 (range = 22.2–45.4). Twenty one were right, 13 left, 2 patients had VATS simultaneous bilateral plication, and 1 had sequential VATS bilateral plication. Paralysis was idiopathic in 17, posttraumatic in 5, postremoval of mediastinal tumor in 4, and postcardiac surgery in 3. All patients presented with lifestyle-limiting dyspnea and orthopnea, three were on nocturnal noninvasive ventilation. Five were diabetic and 16 were smokers. The mean supine forced expiratory volume in the first second was 62.5% of predicted. Twenty two were performed by VATS (63%), three converted to thoracotomy, and 13 were open limited thoracotomy (historic). The mean hospital stay was 4.5 days (range = 1–18, mode 2 days). Intensive therapy unit admission was required in six patients for mechanical ventilation 0 to 3 days. Five patients (14%) had no improvement in symptoms. There were no deaths, no 30-day readmissions, and no long-term neuralgia in this series. Conclusions We found minimal access VATS plication of the diaphragm to be feasible and safe, but no firm conclusions should be drawn from our limited resources. We report the feasibility of concomitant bilateral VATS plication of the diaphragm in two adults, and this was not previously reported in the adult population. There is a need for further good quality, prospective studies, and randomized controlled studies evaluating efficacy of VATS diaphragmatic plication.

Posterolateral thoracotomy is required to gain access to the thoracic cavity. The patient is placed on the operating table in a lateral decubitus position and a single-lung ventilation technique is employed by using a double-lumen endotracheal tube. The incision is made on the side of the chest towards the back between the ribs. Many thoracic surgical procedures can be performed using this approach including lung resections. Pneumonectomy is a surgical procedure to remove the whole lung and is usually performed by posterolateral thoracotomy. It can also be performed using a video-assisted (VATS) technique. Pneumonectomy is indicated where curative surgical resection is not possible with lesser resection. Prior to pneumonectomy, a thorough preoperative assessment of the patient is performed as per the British Thoracic Society guidelines. This procedure leads to considerable reduction in respiratory reserve and is also associated with significant morbidity and mortality. Common complications include arrhythmias, myocardial infarction, pulmonary embolism, pneumonia, empyema, respiratory failure and bronchopleural fistula. The perioperative mortality rate ranges between 6 and 8%. Very dedicated and careful postoperative management is required in specialized centres to avoid complications.

In this issue of Neuron, van Veluw et al. (2020) show that elimination of solutes from the brain along arterial walls is driven by low-frequency arteriolar oscillations and suggest that age-related reduction of this vasomotion may contribute to impaired clearance of Aβ.

Background: Altered collagen architecture, rather than collagen quantity, is a key determinant of abnormal tissue structure-function in idiopathic pulmonary fibrosis (IPF), with the collagen cross-linking enzymes lysyl hydroxylase 2 (LH2) and lysyl oxidase-like 2 (LOXL2) promoting pathological bone-type collagen crosslinking and increased tissue stiffness (Jones et al eLife. 2018;7:e36354). However, the upstream mechanisms regulating this process remain unknown. Objective: To determine the cellular provenance of LOXL2 and LH2 in IPF tissue and identify the mechanisms promoting their dysregulation. Methods: Cellular provenance of LH2 and LOXL2 was analysed using mRNA in-situ hybridisation. IPF lung fibroblasts were cultured under a range of conditions that have been associated with IPF pathogenesis and their effects on LH2 and LOXL2 induction assessed by RTqPCR and Western Blotting. Small-interfering RNAs (siRNA) were transfected into IPF fibroblasts to investigate signalling pathways of interest and their role in regulating LH2 and LOXL2 expression. Results: LH2 and LOXL2 were co-expressed within fibroblastic foci in IPF tissue. Hypoxia-inducible factor (HIF) pathways were the strongest inducers of both LOXL2 and LH2 in IPF fibroblasts. siRNA mediated knockdown of HIF-1α but not HIF-2α prevented LH2 induction, whilst knockdown of both HIF-1α and HIF-2α was required to prevent LOXL2 induction. Conclusions: Our results suggest that HIF pathway activation via LH2/LOXL2 may be a core regulator of bone-type collagen fibrillogenesis in IPF.

Introduction: The lung epithelium is a functional interface between our body and the outside environment and it plays a key role in the respiratory physiology and pathology. Recurring alveolar epithelial injury is a hallmark of idiopathic pulmonary fibrosis (IPF) that lead to aberrant fibroblast activation resulting in the progressive destruction of the lung parenchymal architecture and impairment of gas exchange. The complex interactions between the persistent injured epithelium and the abnormal activated fibroblasts seems to be the main factors determining initiation and progression of the disease in association with aging, environmental exposure and genetic susceptibility. A better understanding of the epithelial-mesenchymal signaling in IPF is needed for the development of more efficient therapeutic strategies that promote restoration of normal epithelium integrity and limit the progression of fibrosis. Aim: Characterize the paracrine signaling between alveolar cells (AECs) and lung fibroblasts (FFs) and investigate its role in injury/repair of the epithelium. Methods: we established and characterize an ex-vivo co-culture models of AECs and FFs to mimic the epithelial-mesenchymal paracrine interaction in injured alveoli. Results and Conclusions: we detected abnormal epithelialization in co-culture of AECs and IPF FFs compared to co-culture of AECs and healthy FFs. Mass spectrometry analysis of fibroblasts secretome identified different extracellular matrix (ECM) proteins that are involved in tissue repair and fibrosis. Gene silencing of the ECM protein osteonectin in IPF FFs restored the alveolar epithelium homeostasis. These results suggest that IPF FFs secrete factors that alter the normal epithelial repair responses preventing the restoration of tissue homeostasis.

Introduction: Idiopathic pulmonary fibrosis (IPF) is a progressive disease with a poor prognosis and limited therapeutic options. Increasing evidence suggests that alveolar epithelial damage and resulting abnormal epithelial-mesenchymal crosstalk may contribute to the aberrant wound healing response observed in the lungs of IPF patients. The epithelial-mesenchymal trophic unit (EMTU) describes the functional interactions between epithelial cells, mesenchymal cells and the ECM which are necessary to regulate lung development, repair of damaged tissue and inflammatory responses. Thus characterization of EMTU in IPF will help to understand the pathofisiology of the disease. Aim: Characterize the paracrine crosstalk between alveolar cells (AECs) and lung fibroblasts (FFs) and investigate its role in injury and repair of the epithelium. Methods: we enstablished an ex-vivo co-culture models of AECs and FFs to mimic the EMTU of the respiratory epithelium. Epithelial cell layer intergrity was assed by immunofluorescence. Oxidative stress and injury/repair response were analysed using qPCR, western blot and time-laspe microscopy. Results and Conclusions: we detected abnormal epithelialization in co-culture of AECs and IPF FFs compared to co-culture of AECs and healthy FFs while western blot and qPCR data show increase in markers of cell motility. These results suggest that IPF FFs alter the normal epithelial repair responses preventing the restoration of lung tissue homeostasis. Therefore characterization of the EMTU in IPF will help the development of more efficient therapeutic strategies to limit the progression of fibrosis and promote restoration of the normal lung epithelium in IPF patients.

The contribution of epithelial-mesenchymal transition (EMT) to human lung fibrogenesis is controversial. Here we provide evidence that ZEB1-mediated EMT in human alveolar epithelial type II (ATII) cells contributes to the development of lung fibrosis by paracrine signalling to underlying fibroblasts. Activation of EGFR-RAS-ERK signalling in ATII cells induced EMT via ZEB1. ATII cells had extremely low extracellular matrix gene expression even after induction of EMT, however conditioned media from ATII cells undergoing RAS-induced EMT augmented TGFβ-induced profibrogenic responses in lung fibroblasts. This epithelial-mesenchymal crosstalk was controlled by ZEB1 via the expression of tissue plasminogen activator (tPA). In human fibrotic lung tissue, nuclear ZEB1 expression was detected in alveolar epithelium adjacent to sites of extracellular matrix (ECM) deposition, suggesting that ZEB1-mediated paracrine signalling has the potential to contribute to early fibrotic changes in the lung interstitium. Targeting this novel ZEB1 regulatory axis may be a viable strategy for the treatment of pulmonary fibrosis.

Immune evasion is a hallmark of cancer. Losing the ability to present neoantigens through human leukocyte antigen (HLA) loss may facilitate immune evasion. However, the polymorphic nature of the locus has precluded accurate HLA copy-number analysis. Here, we present loss of heterozygosity in human leukocyte antigen (LOHHLA), a computational tool to determine HLA allele-specific copy number from sequencing data. Using LOHHLA, we find that HLA LOH occurs in 40% of non-small-cell lung cancers (NSCLCs) and is associated with a high subclonal neoantigen burden, APOBEC-mediated mutagenesis, upregulation of cytolytic activity, and PD-L1 positivity. The focal nature of HLA LOH alterations, their subclonal frequencies, enrichment in metastatic sites, and occurrence as parallel events suggests that HLA LOH is an immune escape mechanism that is subject to strong microenvironmental selection pressures later in tumor evolution. Characterizing HLA LOH with LOHHLA refines neoantigen prediction and may have implications for our understanding of resistance mechanisms and immunotherapeutic approaches targeting neoantigens. VIDEO ABSTRACT.

Development of distant metastases from renal cell carcinoma (RCC) is a frequent occurrence and, in nearly 95% of the cases, secondary lesions present within 5 years following nephrectomy. We performed a left pneumonectomy for a peri-hilar lung mass in an 81-year-old man with history of kidney cancer, resected 37 years earlier. Histopathological examination revealed a solitary lung metastasis from RCC, relapsed after an extraordinary 37-year time interval. To the best of our knowledge, this remarkable case represents the longest time interval between radical nephrectomy for RCC and the occurrence of a pulmonary metastasis. After an uneventful post-operative recovery, there are no signs of disease recurrence at a 3-year follow-up. The possibility of a lung metastasis should be taken into account in patients with history of RCC who present with pulmonary nodules, even decades after treatment of the primary neoplasm.

Therapies that boost the anti-tumor responses of cytotoxic T lymphocytes (CTLs) have shown promise; however, clinical responses to the immunotherapeutic agents currently available vary considerably, and the molecular basis of this is unclear. We performed transcriptomic profiling of tumor-infiltrating CTLs from treatment-naive patients with lung cancer to define the molecular features associated with the robustness of anti-tumor immune responses. We observed considerable heterogeneity in the expression of molecules associated with activation of the T cell antigen receptor (TCR) and of immunological-checkpoint molecules such as 4-1BB, PD-1 and TIM-3. Tumors with a high density of CTLs showed enrichment for transcripts linked to tissue-resident memory cells (TRM cells), such as CD103, and CTLs from CD103(hi) tumors displayed features of enhanced cytotoxicity. A greater density of TRM cells in tumors was predictive of a better survival outcome in lung cancer, and this effect was independent of that conferred by CTL density. Here we define the 'molecular fingerprint' of tumor-infiltrating CTLs and identify potentially new targets for immunotherapy.

Following a pneumonectomy, excessive mediastinal shift can cause rare complications involving the post-pneumonectomy cavity, which can become the seat of herniation of the residual lung and of the heart. We herein report an even more rare event, entailing an impressive herniation of the actual entire post-pneumonectomy cavity through an intercostal space, which developed spontaneously nearly 3 years after surgery. Surgical excision of the hernia sac and repair of the defect with polypropylene mesh provided adequate treatment and good cosmetic results. Postoperative recovery was uneventful and no signs of recurrence have been observed.

Thoracoplasty is a technique used to obliterate residual intrapleural spaces after lung resection for infection or other causes. It involves multiple osteotomies on several ribs and then collapsing them into the space to be obliterated; however, this results in a distorted and asymmetrical chest wall. We report a case of a 34-year-old female with completely destroyed right upper lobe secondary to chronic Aspergillus infection. She underwent a completion right upper lobectomy and modified thoracoplasty with the use of a breast implant to obliterate the residual pleural space without any distortion of the chest wall, with an excellent outcome.

Aims: To (i) investigate the effects of Romidepsin in vitro using fibroblasts and alveolar cells (ATII); (ii) in vivo in Bleomycin treated mice; and (iii) to identify biomarkers in order to monitor response to therapy in a future clinical trial. Background: Idiopathic pulmonary fibrosis (IPF) is a complex chronic fibroproliferative disease of unknown aetiology and with limited therapeutic options.Numerous 9single pathway9 agents have failed to show efficacy in IPF clinical trial. By targeting multiple genes and pathways, HDAC inhibitors offer novel therapeutic strategies that could be used alone or in combination with existing agents (Pirfenidone and Nintedanib). Methods: Fibroblast and ATII cell proliferation were determined by cell counting and MTS assay. Myofibroblast differentiation was analysed by western blotting (WB) for α -SMA and Lysyl Oxidase (LOX). The antifibrotic effects of Romidepsin on bleomycin treated mice were assessed by RTqPCR, histology and WB. Broncho-alveolar-lavage (BAL) fluid from IPF patients was analysed by WB. Results: Romidepsin caused a strong inhibition of IPF fibroblast proliferation, myofibroblast differentiation and secretion of LOX. Comparison of the effect of Romidepsin on ATII cells and IPF fibroblasts showed that the ATII cells were significantly less sensitive. Romidepsin reduced bleomycin-induced lung fibrosis in mice and suppressed the expression of LOX. We detected elevated levels of LOX in the BALF of IPF patients. Conclusions: Romidepsin shows strong anti-fibrotic effects without harmful consequences on ATII cells. It is therefore a potential novel anti-fibrotic therapy and LOX may be a potential biomarker of response.

IntroductionLung cancer is the leading cause of cancer-related death worldwide. The discovery of new biomarkers could aid early diagnosis and monitoring of recurrence following tumor resection.MethodsWe have prospectively collected serum from 97 lung cancer patients undergoing surgery with curative intent and compared their serum proteomes with those of 100 noncancer controls (59 disease-free and 41 with a range of nonmalignant lung conditions). We initially analyzed serum from 67 lung cancer patients and 73 noncancer control subjects by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry using immobilized metal affinity capture ProteinChip arrays and subsequently validated our findings with an independent analysis of 30 lung cancer patients and 27 noncancer subjects.ResultsThe data from both experiments show many significant differences between the serum proteomes of lung cancer patients and nondiseased control subjects, and a number of these polypeptides have been identified. However, the profiles of patients with benign lung diseases resembled those of lung cancer patients such that very few significant differences were found when these cohorts were compared.ConclusionsThis report provides clear evidence of the need to account for the confounding effects of benign diseases when designing lung cancer serum biomarker discovery projects.

Endoscopic harvesting of the long saphenous vein has been introduced to decrease the morbidity of obtaining venous conduit for coronary artery bypass grafting. Herein is described an endoscopic method using carbon dioxide insufflation into the tissues around the vein. This has several advantages; improved vision, no physical retraction required, easier development of tissue planes, and improved hemostasis.

7560 Background: Mesothelioma is a rare, aggressive cancer associated with asbestos inhalation. Treatment results are poor regardless of the modality used, with median survival of 4-18 months. Immu...