Project description:BackgroundThe diagnosis of active pulmonary tuberculosis (TB) remains a challenge in clinic, especially for sputum negative pulmonary TB. Bronchoalveolar lavage fluid (BALF) has higher sensitivity than sputum for detection of Mycobacterium tuberculosis (Mtb). However, bronchoscopy is invasive and costly, and not suitable for all patients. In order to make TB patients get more benefit from BALF for diagnosis, we explore which indicator might be used to optimize the choice of bronchoscopy.MethodsA total of 1539 sputum-smear-negative pulmonary TB suspects who underwent bronchoscopy were recruited for evaluation. The sensitivity, specificity and accuracy of Mtb detection in sputum and BALF were compared. Odds ratios and 95% confidence intervals were used to assess variables that associated with positive acid-fast bacilli (AFB) smear, Mtb culture and nucleic acid amplification test (NAAT) of BALF in sputum-negative and non-sputum-producing pulmonary TB suspects.ResultsBALF has significantly higher sensitivity (63.4%) than sputum (43.5%) for Mtb detection by culture and NAAT. 19.7% (122/620) sputum-negative and 40.0% (163/408) non-sputum-producing suspects had positive bacteriological results in BALF. Among sputum-negative and non-sputum-producing pulmonary TB suspects, the positivity of Mtb detection in BALF is associated with a younger age, the presence of pulmonary cavities and a positive result of interferon-gamma release assay (IGRA). Sputum-negative patients under 35 years old with positive IGRA and pulmonary cavity had 84.8% positivity of Mtb in BALF.ConclusionsOur study indicated that combination of age, the presence of pulmonary cavity, and the result of IGRA is useful to predict the positivity of Mtb detection in BALF among sputum-negative and non-sputum producing pulmonary TB suspects. Those who are under 35 years old, positive for the presence of pulmonary cavity and IGRA, should undergo bronchoscopy to collect BAFL for Mtb tests, as they have the highest possibility to get bacteriologically confirmation of TB.
Project description:BackgroundIt is now possible to comprehensively characterize the microbiota of the lungs using culture-independent, sequencing-based assays. Several sample types have been used to investigate the lung microbiota, each presenting specific challenges for preparation and analysis of microbial communities. Bronchoalveolar lavage fluid (BALF) enables the identification of microbiota specific to the lower lung but commonly has low bacterial density, increasing the risk of false-positive signal from contaminating DNA. The objectives of this study were to investigate the extent of contamination across a range of sample densities representative of BALF and identify features of contaminants that facilitate their removal from sequence data and aid in the interpretation of BALF sample 16S sequencing data.ResultsUsing three mock communities across a range of densities ranging from 8E+ 02 to 8E+ 09 16S copies/ml, we assessed taxonomic accuracy and precision by 16S rRNA gene sequencing and the proportion of reads arising from contaminants. Sequencing accuracy, precision, and the relative abundance of mock community members decreased with sample input density, with a significant drop-off below 8E+ 05 16S copies/ml. Contaminant OTUs were commonly inversely correlated with sample input density or not reproduced between technical replicates. Removal of taxa with these features or physical concentration of samples prior to sequencing improved both sequencing accuracy and precision for samples between 8E+ 04 and 8E+ 06 16S copies/ml. For the lowest densities, below 8E+ 03 16S copies/ml BALF, accuracy and precision could not be significantly improved using these approaches. Using clinical BALF samples across a large density range, we observed that OTUs with features of contaminants identified in mock communities were also evident in low-density BALF samples.ConclusionRelative abundance data and community composition generated by 16S sequencing of BALF samples across the range of density commonly observed in this sample type should be interpreted in the context of input sample density and may be improved by simple pre- and post-sequencing steps for densities above 8E+ 04 16S copies/ml.
Project description:The long-term goal of our study is to identify chronic obstructive pulmonary disease (COPD)-related bronchoalveolar lavage fluid (BALF) nitroproteins to clarify COPD pathological mechanisms and to discover biomarkers of COPD. The goal of the present study was to detect the presence of, and potential roles of, nitroproteins in, human ex-smoker (without COPD) BALF samples. Nitroproteins were immunoprecipitated from two separate BALF samples, and digested with trypsin; and tryptic peptides were analyzed with matrix-assisted laser desorption/ionization (MALDI)-tandem mass spectrometry (MS/MS). Each MS/MS spectrum was composed of accumulated scans (n = 50-100). The MS/MS data were searched with BioWorks 2.0 TuboSequest in the SwissProt database to generate the amino acid sequence, which was evaluated manually. Eleven nitrotyrosine sites were identified in eight proteins, including progestin and adipoQ receptor family member III, zinc finger protein 432, proteasome subunit alpha type 2, NADH-ubiquinone oxidoreductase B14, slit homolog 1 protein, lysozyme, aldose 1-epimerase, and PTS system lactose-specific EIICB component. Each nitrotyrosine site was located within a specific protein domain and motif. Those identified nitrated proteins could be involved in multiple functional metabolic systems, including transcriptional regulation, mitochondrial complex, immune system, and energy metabolism.
Project description:Global-scale examination of protein phosphorylation in human biological fluids by phosphoproteomics approaches is an emerging area of research with potential for significant contributions towards discovery of novel biomarkers. In this pilot work, we analyzed the phosphoproteome in human bronchoalveolar lavage fluid (BAL) from nondiseased subjects. The main objectives were to assess the feasibility to probe phosphorylated proteins in human BAL and to obtain the initial catalog of BAL phosphoproteins, including protein identities and exact description of their phosphorylation sites. We used a gel-free bioanalytical workflow that included whole-proteome digestion of depleted BAL proteins, enrichment of phosphopeptides by immobilized metal ion affinity chromatography (IMAC), LC-MS/MS analyses with a linear ion trap mass spectrometer, and searches of a protein sequence database to generate a panel of BAL phosphoproteins and their sites of phosphorylation. Based on sequence-diagnostic MS/MS fragmentation patterns, we identified a collection of 36 phosphopeptides that contained 26 different phosphorylation sites. These phosphopeptides mapped to 21 phosphoproteins including, for example, vimentin, plastin-2, ferritin heavy chain, kininogen-1, and others. The characterized phosphoproteins have diverse characteristics in terms of cellular origin and biological function. To the best of our knowledge, results of this study represent the first description of the human BAL phosphoproteome.
Project description:The aim of the project was to explore large extracellular vesicles capacity to seperate non lung cancer from lung cancer cases. A case control study of patients suspected for lung cancer (12 non lung cancer and 12 lung cancers). The raw files are labeled according to clinical status. Small and large extracellular vesicles were isolated by differential centrifugation. The proteome of full BAL, vesicle depleted BAL, small and large extracellular vesicles were characterized by LC-MS. Small extracellular vesicles were further analyzed by nanoparticle tracking analysis, Transmission electron microscopy and western blots.
Project description:Rationale: Airspace macrophages are the most abundant cell in airspaces and are viewed as a homogeneous population during health. Single cell RNA sequencing allows for examination of transcriptional heterogeneity between cells and between individuals. Understanding the conserved repertoire of airspace leukocytes during health is essential to understanding cellular programing during disease. Objective: We sought to determine the transcriptional heterogeneity of human bronchoalveolar lavage cells in healthy adults. Methods: Ten healthy subjects underwent bronchoscopy. Cells obtained from lavage fluid were subjected to single cell RNA sequencing. Unique cell populations and putative functions were identified. Transcriptional profiles were compared across individuals. Measurements and Main Results: Based on transcriptional profiling we identify highly conserved macrophage, monocyte-like, lymphocyte, dendritic cell, and cycling cell populations. We define two unique subgroups of resident airspace macrophages - one defined by a pro-inflammatory profile and one by metallothionein gene expression. We identify distinct subsets of monocyte-like cells and directly compared them to peripheral blood mononuclear cells. Finally, we compare global macrophage and monocyte programing between male and female subjects. Conclusions: Healthy human airspaces contain multiple populations of leukocytes that are highly conserved between individuals and between the sexes. Resident macrophages comprise the largest population and include novel subsets defined by inflammatory and metal-binding gene signatures. Monocyte-like cells within the airspaces are transcriptionally distinct from circulating blood cells and include a rare population defined by expression of cell-matrix interaction genes. This study is the first to define airspace immune cell heterogeneity and identifies three previously unrecognized myeloid cell subsets.
Project description:Mass spectrometry based proteome analysis on an observational prospective cohort consisting of 90 suspected lung cancer cases (suspicious=7, no lung cancer suspicion=47 and lung cancer=36 as diagnosed in 2014) which were followed during two years (suspicious=2, no lung cancer suspicion= 39 and Lung cancer=49).
Project description:Background: Aspergillus colonization after lung transplant is associated with an increased risk of chronic lung allograft dysfunction (CLAD). We hypothesized that gene expression during Aspergillus colonization could provide clues to CLAD pathogenesis. Methods: We examined transcriptional profiles in 3 or 6-month surveillance bronchoalveolar lavage fluid cell pellets from recipients with A. fumigatus colonization (n=12) and without colonization (n=10). Among the Aspergillus colonized, we also explored profiles in those who developed CLAD (n=6) or remained CLAD free (n=6). Transcription profiles were assayed with the HG-U133 Plus 2.0 microarray (Affymetrix). Statistical Analysis: Differential gene expression analyses were performed to select candidate lists of genes. Functional analyses on these selected genes were explored.
Project description:The analysis of airway fluid, as sampled by bronchoalveolar lavage (BAL), provides a minimally invasive route to interrogate lung biology in health and disease. Here, we used immunodepletion, coupled with gel- and label-free LC-MS/MS, for quantitation of the BAL fluid (BALF) proteome in samples recovered from human subjects following bronchoscopic instillation of saline, lipopolysaccharide (LPS) or house dust mite antigen into three distinct lung subsegments. Among more than 200 unique proteins quantified across nine samples, neutrophil granule-derived and acute phase proteins were most highly enriched in the LPS-exposed lobes. Of these, peptidoglycan response protein 1 was validated and confirmed as a novel marker of neutrophilic inflammation. Compared to a prior transcriptomic analysis of airway cells in this same cohort, the BALF proteome revealed a novel set of response factors. Independent of exposure, the enrichment of tracheal-expressed proteins in right lower lung lobes suggests a potential for constitutive intralobar variability in the BALF proteome; sampling of multiple lung subsegments also appears to aid in the identification of protein signatures that differentiate individuals at baseline. Collectively, this proof-of-concept study validates a robust workflow for BALF proteomics and demonstrates the complementary nature of proteomic and genomic techniques for investigating airway (patho)physiology.
Project description:The lung is an important reservoir of human immunodeficiency virus (HIV). Individuals infected with HIV are more prone to pulmonary infections and chronic lung disorders. We hypothesized that comprehensively profiling the proteomic landscape of bronchoalveolar lavage fluid (BALF) in patients with HIV would provide insights into how this virus alters the lung milieu and contributes to pathogenesis of HIV-related lung diseases. BALF was obtained from five HIV-negative (HIV(-)) and six asymptomatic HIV-positive (HIV(+)) subjects not on antiretroviral therapy. Each sample underwent shotgun proteomic analysis based on HPLC-tandem mass spectrometry. Differentially expressed proteins between the groups were identified using statistical methods based on spectral counting. Mechanisms of disease were explored using functional annotation to identify overlapping and distinct pathways enriched between the BALF proteome of HIV(+) and HIV(-) subjects. We identified a total of 318 unique proteins in BALF of HIV(-) and HIV(+) subjects. Of these, 87 were differentially up- or downregulated between the two groups. Many of these differentially expressed proteins are known to interact with key HIV proteins. Functional analysis of differentially regulated proteins implicated downregulation of immune responses in lungs of HIV(+) patients. Combining shotgun proteomic analysis with computational methods demonstrated that the BALF proteome is significantly altered during HIV infection. We found that immunity-related pathways are underrepresented in HIV(+) patients. These findings implicate mechanisms whereby HIV invokes local immunosuppression in the lung and increases the susceptibility of HIV(+) patients to develop a wide range of infectious and noninfectious pulmonary diseases.