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The many faces of the hygiene hypothesis
Bianca Schaub1, Roger Lauener, Erika von Mutius
1University Children's Hospital Munich, Dr von Haunersches Kinderspital, Pediatric Pulmonary Division, LMU Munich, Germany. bianca.schaub@med.uni-muenchen.de
The Journal of Allergy and Clinical Immunology
|May 6, 2006
Summary
The hygiene hypothesis suggests early life infections and microbial exposures may protect against allergic diseases. Research explores microbial roles in immunity, potentially leading to new allergy prevention and treatments.
Area of Science:
- Immunology
- Epidemiology
- Allergy Research
Background:
- The hygiene hypothesis, proposed 15 years ago, suggests infections and unhygienic contact protect against allergic illnesses.
- Numerous modifications have refined the hypothesis, focusing on infections, environmental microbes, and immune responses.
Purpose of the Study:
- To review the evolving understanding of the hygiene hypothesis.
- To explore the interplay of host immunity, microbial factors, environmental exposures, and genetics in allergic diseases.
- To highlight the importance of immune system interactions in allergic conditions, including asthma phenotypes.
Main Methods:
- Review of epidemiological, clinical, and immunological research.
- Analysis of three major research tracts: overt infections, environmental microbial compounds, and their impact on immunity.
- Discussion of host-microbe interactions and genetic influences on allergic disease development.
Main Results:
- No single unifying concept has emerged, but a complex interplay is evident.
- Factors include host immune responses, microbial characteristics, environmental exposure levels and diversity, and genetic background.
- These influences are determinants for various allergic illnesses, including asthma syndromes.
Conclusions:
- The complex interactions between the immune system, microbes, environment, and genetics are key determinants of allergic diseases.
- While direct practical applications are not yet available, findings hold significant potential for future preventive and therapeutic strategies.
- Further research into these interactions could lead to novel approaches for managing and preventing allergic conditions.
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