AHR and chronic obstructive pulmonary disease: We have previously shown that the AhR attenuates pulmonary neutrophilia in response to acute and sub-chronic cigarette smoke exposure (Thatcher et al., 2007; de Souza et al., 2014; Rico de Souza et al., 2021) and prevents the development of a COPD-like phenotype (Guerrina et al., 2021).