TLR Activation and Allergic Disease: Early Life Microbiome and Treatment

  • Kathryn R. MichelsEmail author
  • Nicholas W. Lukacs
  • Wendy Fonseca
Basic and Applied Science (I Lewkowich, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Basic and Applied Science


Purpose of Review

Allergy and asthma are growing problems in the developed world. The accelerated increase of these diseases may be related to microbiome modification that leads to aberrant activation of Toll-like receptors (TLRs). Current research supports the concept that changes in microbial communities in early life impact TLR activation, resulting in an altered risk for the development of asthma and allergies.

Recent Findings

Prenatal and early childhood events that generate microbiome modification are closely related with TLR activation. Early childhood exposure to a rich array of TLR agonists, particularly lipopolysaccharide, strongly predicts protection against allergic disease later in life even when other lifestyle factors are accounted for. Genetic deletion of TLR signaling components in mice results in reduced function of tolerogenic cell populations in the gut. In contrast, weak TLR signaling can promote allergic sensitization later in life.


This review summarizes the role of TLR signaling in microbiome-mediated protection against allergy.


TLRs Allergy Microbiome Asthma TLR sensitization Tregs Tolerogenic DC 


Compliance with Ethical Standards

Conflict of Interest

The authors declare no conflicts of interest relevant to this manuscript.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.


Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major Importance

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Kathryn R. Michels
    • 1
    Email author
  • Nicholas W. Lukacs
    • 1
    • 2
  • Wendy Fonseca
    • 1
  1. 1.Department of PathologyUniversity of Michigan Medical SchoolAnn ArborUSA
  2. 2.Mary H. Weiser Food Allergy CenterUniversity of MichiganAnn ArborUSA

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