In a model of severe bronchiolitis using IRF7-deficienct mice, neonatal infection with PVM led to release of IL-33 and HMGB1 (high-mobility group box 1), another nuclear alarmin, both of which contributed to ILC2 proliferation, type 2 inflammation, and airway remodeling (195). This evidence concerns the gene HMGB1 and bronchiolitis.