Notably, IAS expression strongly correlated with the expression of CDKN1A and with senescence (SenMayo signature), with cells double positive for the IAS and senescence markers (CDKN1Ahigh/IAShigh and SenMayohigh/IAShigh) being significantly more abundant in patients with IPF compared to control donors, both when studied in the whole lung or in several individual cell types (Fig. 6i–l and Extended Data Fig. 7d,e). The gene discussed is CDKN1A; the disease is idiopathic pulmonary fibrosis.