MLKL and bronchiolitis: The third study demonstrated that pharmacological inhibition of the programmed death response (receptor-interacting serine/threonine-protein kinase 1 (RIPK1) or mixed lineage kinase domain like pseudokinase (MLKL) inhibition) both in vitro and in vivo reduced HMGB1 release and attenuated the development of bronchiolitis and type 2 inflammation in vivo in IRF7-deficient mice, a strain of animals predisposed to developing severe bronchiolitis in response to PVM infection [130].