IL1A and chronic obstructive pulmonary disease: Interestingly, the increased AIM2 expression in stable COPD-derived PBMCs was not associated with a higher activity of AIM2 after stimulation with Poly dA:dT in terms of IL-1α release (Figures 1A,B, red bars), as instead observed for exacerbated patients (Figures 1A,B, black bars).