Examining the Interaction between Allergic Asthma and Air Pollution: a Potential Role for Trained Immunity

Area of Science:

• Environmental Health
• Immunology
• Respiratory Medicine

Background:

• Asthma incidence has risen globally, paralleling increased air pollution.
• The biological mechanisms linking air pollution to asthma are not fully understood.
• Innate immune memory, or trained immunity, is implicated in asthma, but its role in air pollution's effects is unclear.

Purpose of the Study:

• To review emerging findings on how air pollution influences trained immunity in asthma.
• To synthesize current knowledge on air pollution's impact on inflammatory lung diseases.
• To highlight the role of trained immunity in air pollution-induced asthma.

Main Methods:

• Literature review of recent studies on air pollution, trained immunity, and asthma.
• Synthesis of evidence linking environmental exposures to immune system changes.
• Analysis of molecular mechanisms including epigenomic and metabolic alterations.

Main Results:

• Air pollutants induce epigenetic modifications like gene acetylation and methylation.
• Pollutants disrupt the metabolism of innate immune cells.
• These changes align with characteristics of trained immunity, suggesting a mechanism for long-term immune effects.
• Air pollution imprints lasting epigenomic and immunometabolic changes on innate immune cells.

Conclusions:

• Air pollution contributes to asthma susceptibility and severity by shaping trained immunity.
• Epigenomic and immunometabolic alterations in innate immune cells are key pathways.
• Further mechanistic research is needed to understand how pollutants dysregulate innate immune memory.