Interaction of allergic airway inflammation and innate immunity: hygiene and beyond

Area of Science:

• * Immunology
• * Respiratory Medicine
• * Microbiology

Background:

• * The lungs are continuously exposed to environmental microbes, with respiratory infections being common.
• * The hygiene hypothesis suggests early microbial exposure protects against asthma by modulating the immune system.
• * Asthma exacerbations are often triggered by infections, yet childhood microbial exposure may be protective.

Purpose of the Study:

• * To explore the complex interplay between microbial stressors and the immune system in allergic airway diseases.
• * To review animal models investigating the effects of microbial stimuli on allergic lung inflammation.
• * To understand how allergic inflammation affects antimicrobial defense.

Main Methods:

• * Review of animal models examining the impact of bacterial products on allergen-induced lung inflammation.
• * Analysis of studies investigating the interaction between the innate and adaptive immune systems and microbial challenges.
• * Examination of how allergic inflammation influences susceptibility to bacterial infections.

Main Results:

• * Bacterial products have demonstrated a protective effect against allergen-induced lung inflammation in various studies.
• * Allergic inflammation can impair the lung's antimicrobial defenses, increasing susceptibility to bacterial infections.
• * Animal models are crucial for dissecting the immune system's response to microbial stressors in allergic diseases.

Conclusions:

• * The relationship between microbial exposure, the immune system, and allergic airway diseases is intricate.
• * Animal models provide valuable insights into the mechanisms underlying asthma and respiratory infections.
• * Further research is needed to fully elucidate the protective and detrimental roles of microbes in lung health.