Bronchial epithelium in children: a key player in asthma

Abstract

Bronchial epithelium is a key element of the respiratory airways. It constitutes the interface between the environment and the host. It is a physical barrier with many chemical and immunological properties. The bronchial epithelium is abnormal in asthma, even in children. It represents a key component promoting airway inflammation and remodelling that can lead to chronic symptoms. In this review, we present an overview of bronchial epithelium and how to study it, with a specific focus on children. We report physical, chemical and immunological properties from ex vivo and in vitro studies. The responses to various deleterious agents, such as viruses or allergens, may lead to persistent abnormalities orchestrated by bronchial epithelial cells. As epithelium dysfunctions occur early in asthma, reprogramming the epithelium may represent an ambitious goal to induce asthma remission in children. @ERSpublications Bronchial epithelium is a morphological and functional dysregulated gatekeeper in asthmatic children http://ow.ly/Y4MaM

Intranasal administration of mesenchymoangioblast‐derived mesenchymal stem cells abrogates airway fibrosis and airway hyperresponsiveness associated with chronic allergic airways disease

“…This proliferation is particularly extensive in severe asthma, where expansion of the epithelium leads to airway obstruction (39). Given that this reprogramming occurs early in the pathogenesis of asthma (40), asthma therapy should target the epithelium. When administered through IV injection, MCA‐MSCs did not significantly affect the Ova‐induced epithelial thickness.…”

Prenatal particulate matter exposure and wheeze in Mexican children

“…We can hypothesize that early toxicant exposure may impact the global transcriptional program of progenitor cells meant to differentiate into bronchial epithelium and other crucial components of future airway structure and defense. 37 However, further work is needed in order to better elucidate windows of susceptibility to these exposures.…”

Pro‐inflammatory mediator responses from neonatal airway epithelial cells and early childhood wheeze

“…There is a substantial literature, summarised in two recent reviews, which demonstrates that in vitro AEC function is different in children with asthma compared to those without asthma but what has been uncertain is whether the AEC dysfunction is the cause or the consequence of asthma. Nasal AEC from children with wheeze released less IL‐8/CXCL8, IL‐6, and GMCSF compared to non‐wheezing controls and bronchial AEC from adults with asthma have evidence of reduced innate immune responses after exposure to rhinovirus .…”

“…The AEC provides a physical barrier against penetration of environmental exposures into the respiratory tissues, and this cell layer is now understood to be an important component of the innate immune system. Furthermore, AEC function is known to be different in children and adults with asthma compared to their non‐asthmatic peers . Although it is known that AEC abnormalities are present in asthma, the fundamental question as to whether this is present at birth, that is, preceding the development of asthma and wheezing illness, remains unanswered.…”