Microglia Activation in Asthma
The goal of this clinical trail is to learn about how asthma influences brain function. The main questions it aims to answer are: * How airway inflammation in asthma affects the brain; and, * Whether airway inflammation in asthma is related to symptoms of depression and anxiety Over the course of 6 visits, participants will: * Complete questionnaires * Complete computer tasks * Undergo allergy skin test * Undergo breathing tests including two whole lung allergen challenges * Give four blood samples * Complete brain imaging scans
• Individuals with no health concerns that might affect the outcome of the study.
• Age 18-75 years of age.
• Physician diagnosis of asthma for at least six months prior to screening (can be determined at the discretion of an asthma/allergy physician member of the study team). Mild asthma will be defined as asthma that is well controlled with low-intensity treatment, e.g., SABA alone, as-needed low-dose ICS-LABA, or low-dose ICS plus as-needed SABA.
• An increase in FEV1 \> 10% predicted after up to 8 puffs of albuterol OR positive methacholine defined as PD20 ≤ 400 mcg. (Historical data that is approved by the investigator is acceptable).
• FEV1 ≥ 75% predicted at screening Visit 0a.FEV1 ≥ 70% predicted at baseline.
• Positive immediate skin test for allergies to cat hair and reports asthma symptoms to cats, house dust mite and reports asthma symptoms to dust, or ragweed and reports asthma symptoms to ragweed (historical data documented within the last 5 years with our research group is acceptable).
• Ability to tolerate a simulated MRI brain scanning session.
• In the opinion of the investigator, capable and willing to grant written informed consent and cooperate with study procedures and requirements.
• High-affinity TSPO-binding genotype. Mixed (high/low) binding-affinity genotype may be included at PIs discretion.