Dataset Information

A detailed phenotypic analysis of immune cell populations in the bronchoalveolar lavage fluid of atopic asthmatics after segmental allergen challenge.

ABSTRACT: BACKGROUND:Atopic asthma is characterized by intermittent exacerbations triggered by exposure to allergen. Exacerbations are characterized by an acute inflammatory reaction in the airways, with recruitment of both innate and adaptive immune cells. These cell populations as well as soluble factors are critical for initiating and controlling the inflammatory processes in allergic asthma. Detailed data on the numbers and types of cells recruited following allergen challenge is lacking. In this paper we present an extensive phenotypic analysis of the inflammatory cell infiltrate present in the bronchoalveolar lavage (BAL) fluid following bronchoscopically directed allergen challenge in mild atopic asthmatics. METHODS:A re-analysis of pooled data obtained prior to intervention in our randomized, placebo controlled, double blinded study (costimulation inhibition in asthma trial [CIA]) was performed. Twenty-four subjects underwent bronchoscopically directed segmental allergen challenge followed by BAL collection 48 hours later. The BAL fluid was analyzed by multi-color flow cytometry for immune cell populations and multi-plex ELISA for cytokine detection. RESULTS:Allergen instillation induced pro-inflammatory cytokines (IL-6) and immune modulating cytokines (IL-2, IFN-?, and IL-10) along with an increase in lymphocytes and suppressor cells (Tregs and MDSC). Interestingly, membrane expression of CD30 was identified on lymphocytes, especially Tregs, but not eosinophils. Soluble CD30 was also detected in the BAL fluid after allergen challenge in adult atopic asthmatics. CONCLUSIONS:After segmental allergen challenge of adult atopic asthmatics, cell types associated with a pro-inflammatory as well as an anti-inflammatory response are detected within the BAL fluid of the lung.

SUBMITTER: Boomer JS

PROVIDER: S-EPMC3848528 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A detailed phenotypic analysis of immune cell populations in the bronchoalveolar lavage fluid of atopic asthmatics after segmental allergen challenge.

Boomer Jonathan S JS Parulekar Amit D AD Patterson Brenda M BM Yin-Declue Huiqing H Deppong Christine M CM Crockford Seth S Jarjour Nizar N NN Castro Mario M Green Jonathan M JM

Allergy, asthma, and clinical immunology : official journal of the Canadian Society of Allergy and Clinical Immunology 20130917 1

<h4>Background</h4>Atopic asthma is characterized by intermittent exacerbations triggered by exposure to allergen. Exacerbations are characterized by an acute inflammatory reaction in the airways, with recruitment of both innate and adaptive immune cells. These cell populations as well as soluble factors are critical for initiating and controlling the inflammatory processes in allergic asthma. Detailed data on the numbers and types of cells recruited following allergen challenge is lacking. In t ...[more]

PMID: 24330650

Similar Datasets

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:Segmental instillation of lipopolysaccharide (LPS) by bronchoscopy can be used as a model to safely induce transient airway inflammation in the human lung. The LPS challenge model enables investigation of cellular mechanisms involved in pulmonary inflammatory processes as well as pharmacodynamic analysis of investigational drugs for the treatment of respiratory diseases. Aim of this work was to describe the transcriptomic profile of the human segmental LPS challenge model with contextualization to major respiratory diseases. Pre-challenge bronchoalveolar lavage fluid (BAL) and biopsies were sampled from twenty-eight smoking, healthy subjects, followed by segmental LPS challenge and saline control challenge. Twenty-four hours post instillation, BAL and biopsies were collected from the challenged lung segments. Total RNA of cells from BAL and biopsy samples were sequenced for subsequent data analysis. Differential gene expression analysis resulted in 6316 upregulated differentially expressed genes (DEGs) and 241 downregulated DEG in BAL, but only one downregulated DEG in biopsy samples after LPS challenge compared to saline challenge. Upregulated DEG in BAL were related to molecular functions such as “Inflammatory response” or “antimicrobial humoral immune response mediated by antimicrobial peptide”, enriched biological processes such as “chemokine receptor activity”, and upregulated pro-inflammatory pathways such as “Wnt signaling pathway”, “Ras signaling pathway” or “JAK-STAT signaling pathway”. Furthermore, the segmental LPS challenge model resembled aspects of the five most prevalent respiratory diseases chronic obstructive pulmonary disease (COPD), asthma, pneumonia, tuberculosis and lung cancer and featured similarities with acute exacerbations in COPD (AECOPD) and community-acquired pneumonia (CAP). Overall, our study provides extensive information about the transcriptomic profile from BAL cells and mucosal biopsies following LPS challenge in healthy smokers. It expands the knowledge about the LPS challenge model providing potential overlap with respiratory diseases in general and infection-triggered respiratory insults such as AECOPD in particular.

Dataset Information

A detailed phenotypic analysis of immune cell populations in the bronchoalveolar lavage fluid of atopic asthmatics after segmental allergen challenge.

Publications

A detailed phenotypic analysis of immune cell populations in the bronchoalveolar lavage fluid of atopic asthmatics after segmental allergen challenge.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets