The bronchial microbiome and airway hyperresponsiveness in asthma
The presence of specific bacterial species in the lower airways has previously been associated with asthma. However, given that the vast majority of bacteria are unculturable and that they exist in polymicrobial communities on other human mucosal surfaces, relationships between the airway microbiota and clinical features of asthma are relatively unexplored.
In a study published in the February 2011 issue of The Journal of Allergy and Clinical Immunology (JACI), Huang et al investigated the microbiota present in bronchial epithelium-protected brush specimens from asthmatics using inhaled corticosteroids and healthy subjects. Bacterial communities were profiled using a high-density phylogenetic microarray based on the 16S ribosomal RNA gene. The number of different bacterial types detected in the bronchial microbiome was far greater than previously recognized. Moreover, compared to healthy subjects, asthmatics exhibited significantly higher bacterial burden and diversity in their airways; airway microbiota diversity was significantly correlated with the degree of airway hyperresponsiveness. More specifically, the relative abundance of approximately 100 taxa was positively correlated with airway hyperresponsiveness.
The study's findings illustrate the potential clinical and pathophysiologic relevance of the bronchial microbiome in asthma. Further structural and functional studies of the airway microbiome, especially in asthmatic patients naive to inhaled corticosteroid treatment, may prove key to understanding its contribution to asthma pathogenesis
“Airway Microbiota and Bronchial Hyperresponsiveness in Patients with Sub-optimally Controlled Asthma” Remarks by Huang et al.
(JACI February 2011 / Volume 127, No. 2)
The Journal of Allergy and Clinical Immunology (JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.