Immune development and wheeze: directed by postnatal exposures

Published online: January 14, 2017

Recurrent wheezing in early infancy is a common prelude to development of asthma in later childhood. Identifying patterns of immune development during these early years of life, where personal characteristics and environmental exposures first interact with the immune system, could open the door to new approaches for primary prevention. This could be especially important in low-income urban children, who have high rates of recurrent wheeze and asthma.

In a recent study, published in the The Journal of Allergy and Clinical Immunology (JACI), Gern and colleagues  examined urban children, with an increased risk of asthma and allergy, beginning at birth and continuing through the third year of life, analyzed the immune responses of peripheral blood cells to determine how personal characteristics and urban environmental exposures affect immune development, as well as  identifying patterns of immune development that occurred in children with recurrent wheezing illnesses or early evidence of respiratory allergies.

Personal characteristics such as ethnicity and month of birth affected immune responses. The immune responses at birth most notably had little influence on subsequent patterns of immune development at ages one and three years suggesting that postnatal exposures might shape subsequent responses. In fact, exposure to allergens (such as cockroach and dust mite) and the bacterial product endotoxin were positively associated with certain immune responses. Finally, low anti-inflammatory responses to endotoxin predicted the development of recurrent wheeze by age three.  These findings suggest that early immune development is shaped by postnatal exposures to allergens and microbes, and that immune responses to specific microbial stimuli are associated with the development of allergic sensitization and recurrent wheeze.

The Journal of Allergy and Clinical Immunology (JACI) is an official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.
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