The Impact of Microbiome on Childhood Asthma

This article is a review of current evidence on influence of microbiome on asthma development. The prevalence of asthma and allergic disease  has been on constant increase during the last century. The scientific community has begun to understand more about possible factors that have contributed to the epidemic.  Such sharp rise in prevalence cannot be explained by genetic factors as these changes occur over much longer period of time. Stemming from research based on environmental factors and ‘hygiene hypothesis’, there is a large body of evidence that commensal microbiota is an important regulator of early life immune system development and could protect against subsequent asthma and allergic disease. This review is focused on a broader and mechanistic context of hygiene hypothesis reviewing evidence on how gut and respiratory microbiota shape immune responses and influence asthma risk during childhood. Microbial metabolites, diet and its interaction with host immune system are discussed. Also, dynamics of respiratory microbiota, its determinants and interactions with viral infections during early life that predispose to subsequent childhood asthma are summarised. Conclusion – The composition of gut and respiratory microbiome could determine the risk of childhood asthma development.