Seminars in Immunopathology

, Volume 30, Issue 1, pp 53–62 | Cite as

Defining a role for ambient TLR ligand exposures in the genesis and prevention of allergic diseases



Environmental variables responsible for the increasing allergic disease burden observed in developed countries over the last century have yet to be adequately characterized. Meta-analyses of epidemiological studies presented in the first half of this paper demonstrate a correlation between farm-associated exposures (i.e., livestock, pets, unpasteurized milk, and endotoxin) and a reduction in allergic risk during childhood. Laboratory investigations discussed in the second half of the paper characterize the intrinsic immunostimulatory activities of living environments. Considered together, experimental findings presented herein suggest a novel paradigm by which early life home exposures to microbial products and other allergen-nonspecific immunostimulants modify allergic risk.


Hygiene Hypothesis Toll-like receptor Endotoxin Environment Allergy 


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  1. 1.Departments of Medicine and The Sam and Rose Stein Institute for AgingUniversity of California San DiegoLa JollaUSA

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