ABSTRACT: Comparison of endotracheal aspirate and bronchoalveolar lavage fluid metagenomic next-generation sequencing in severe pneumonia: a nested, matched case-control study
Project description:Some patients infected with Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) develop severe pneumonia and the acute respiratory distress syndrome (ARDS). Distinct clinical features in these patients have led to speculation that the immune response to virus in the SARS-CoV-2-infected alveolus differs from other types of pneumonia. We collected bronchoalveolar lavage fluid samples from 88 patients with SARS-CoV-2-induced respiratory failure and 211 patients with known or suspected pneumonia from other pathogens and subjected them to flow cytometry and bulk transcriptomic profiling. We performed single-cell RNA-seq on 10 bronchoalveolar lavage fluid samples collected from patients with severe COVID-19 within 48 hours of intubation. In the majority of patients with SARS-CoV-2 infection, the alveolar space was persistently enriched in T cells and monocytes. Bulk and single-cell transcriptomic profiling suggested that SARS-CoV-2 infects alveolar macrophages, which in turn respond by producing T cell chemoattractants. These T cells produce interferon-gamma to induce inflammatory cytokine release from alveolar macrophages and further promote T cell activation. Collectively, our results suggest that SARS-CoV-2 causes a slowly-unfolding, spatially-limited alveolitis in which alveolar macrophages harboring SARS-CoV-2 and T cells form a positive feedback loop that drives persistent alveolar inflammation.
Project description:Ventilator associated pneumonia (VAP) is the 2nd most common hospital acquired infection associated with high morbidity, mortality and increased hospitalization. Current practice of diagnosis is based on clinical symptoms and bronchoalvolar lavage (BAL) culture. The procedures of BAL collections are invasive whereas, endotracheal aspirate (ETA), a matrix of upper airway collection is minimally invasive and underexplored in VAP diagnosis. The study describes first in detail characterization of proteome of longitudinal ETA collections from 16 intubated patients including 11 VAP patients and explores potential utility of ETA in VAP diagnosis.
Project description:CX3CR1pos monocytes are mobilized upon infection and undergo monocyte-to-macrophage transition in inflamed tissues. Using scRNA-seq of CD11c+ cells from bronchoalveolar lavage fluid (BALF) infected with IAV (PR/8, H1N1 ,we demonstrate that, during severe viral pneumonia, bone marrow-derived macrophages (BMDM) pass co-ordinated trajectories of pro-inflammatory-to-tissue-healing phenotypes, before differentiating into tissue-resident alveolar macrophages, that retain a long-term tissue-protective phenotype.
Project description:This study aimed to delineate molecular phenotypes of the lung microenvironment across idiopathic interestitial pneumonias, namely interstitial pneumonia with autoimmune features (IPAF)and idiopathic pulmonary fibrosis (IPF) through proteomic analysis of bronchoalveolar lavage fluid (BALF).
Project description:Chronic Lung Allograft Dysfunction (CLAD) is the main limitation to long-term survival after lung transplantation. Although CLAD is usually not responsive to treatment, earlier identification may improve treatment prospects. In a nested case control study, 1-year post transplant surveillance bronchoalveolar lavage (BAL) fluid samples were obtained from incipient CLAD (n=9) and CLAD free (n=8) lung transplant recipients. Incipient CLAD cases were diagnosed with CLAD within 2 years, while controls were free from CLAD for at least 4 years following bronchoscopy. Transcription profiles in the BAL cell pellets were assayed with the HG-U133 Plus 2.0 microarray (Affymetrix). Differential gene expression analysis was performed to identify a candidate list of differentially expressed probe sets.
Project description:We conducted single-cell and T-cell receptor transcriptomic sequencing on the bronchoalveolar lavage fluid from five patients with grade ≥2 immune checkpoint inhibitor-related pneumonitis. Our analyses revealed a prominent enrichment of T cells in the bronchoalveolar lavage fluid of patients with immune checkpoint inhibitor-related pneumonitis.
Project description:Bronchoalveolar lavage samples collected from lung transplant recipients. Numeric portion of sample name is an arbitrary patient ID and AxBx number indicates the perivascular (A) and bronchiolar (B) scores from biopsies collected on the same day as the BAL fluid was collected. Several patients have more than one sample in this series and can be determined by patient number followed by a lower case letter. Acute rejection state is determined by the combined A and B score - specifically, a combined AB score of 2 or greater is considered an acute rejection. Keywords = Bronchoalveolar lavage Keywords = lung transplant Keywords: other
