CD4 and pulmonary emphysema: To explore a potential protective role of Mirlet7 in experimentally induced emphysema, we generated mice which allowed for selective induction of Mirlet7g in T cells using the published rtTA-iLet7 mice crossed to CD4-Cre (herein referred to as let7GOF;Figure 6A; Angelou et al., 2019; Belteki et al., 2005; Pobezinskaya et al., 2019; Wells et al., 2017; Zhu et al., 2011).