Intervention: Segmental airway allergen challenge

Three types of subjects are studied in this arm:

1) Volunteers with neither asthma nor allergy (as established by skin prick testing); 2) Volunteers with allergy (as established by skin prick testing) but without asthma; and 3) Volunteers with both asthma and allergy (as established by skin prick testing)

For each participant with Allergic Asthma, a baseline airway epithelial brushing was performed, allergen was instilled into one segment of the lung, and diluent (control) was instilled into another segment. Both segments were brushed for epithelial cells 24 hours later. After processing brushes to RNA and generating RNA sequencing data, the RNA transcript read counts for each gene underwent variance stabilized log normalization. Then we built a regression model which estimated the difference in miRNA read count in the allergen challenged as compared to the baseline sample and the difference in miRNA read count in the diluent challenged segment as compared to baseline for each participant. The change from baseline read count for each miRNA in the allergen samples was compared to the change in the diluent samples and statistical significance was assessed using the unadjusted p-value(<0.05). The direction of change does not have clinical significance; this was a mechanistic study.

For each participant with Allergic Asthma, a baseline airway epithelial brushing was performed, allergen was instilled into one segment of the lung, and diluent (control) was instilled into another segment. Both segments were brushed for epithelial cells 7 days later. After processing the brushes to RNA and generating RNA sequencing data, the RNA transcript read counts for each gene underwent variance stabilized log normalization. Then we built a regression model which estimated the difference in miRNA read count in the allergen challenged as compared to the baseline sample and the difference in miRNA read count in the diluent challenged segment as compared to baseline for each participant. The change from baseline read count for each miRNA in the allergen samples was compared to the change in the diluent samples and statistical significance was assessed using the unadjusted p-value(<0.05). The direction of change does not have clinical significance; this was a mechanistic study.

) Volunteers with allergy (as established by skin prick testing) but without asthma

Volunteers with neither asthma nor allergy (as established by skin prick testing)

For each participant with Allergic Asthma, a baseline airway epithelial brushing was performed, allergen was instilled into one segment of the lung, and diluent (control) was instilled into another segment. Both segments were brushed for epithelial cells 24 hours later. After processing brushes to RNA and generating RNA sequencing data, the RNA transcript read counts for each gene underwent variance stabilized log normalization. Then we built a regression model which estimated the difference in miRNA read count in the allergen challenged as compared to the baseline sample and the difference in miRNA read count in the diluent challenged segment as compared to baseline for each participant. The change from baseline read count for each miRNA in the allergen samples was compared to the change in the diluent samples and statistical significance was assessed using the unadjusted p-value(<0.05). The direction of change does not have clinical significance; this was a mechanistic study.

Our pre-specified primary outcome was limited to Allergic Asthmatics only. The rationale for this is that participants without allergy or asthma do not respond to Allergen Challenge and therefore the changes in miRNA are uninformative.

Volunteers with both asthma and allergy (as established by skin prick testing)

Participant was not pregnant upon enrollment (confirmed via urine pregnancy test). Participant later notified study team of pregnancy and was withdrawn prior to Visit 2 and Visit 3 bronchoscopies. Event was reported to sponsor and medical monitor.