In parallel, MAIT-enriched regions displayed a transcriptional programme characteristic of tissue-positioned MAIT cells, prominently expressing KLRB1 and DPP4—consistently highlighted in MAIT signatures from liver scRNA-seq [8], COVID-19 MAIT activation studies [9], and anti-mycobacterial response profiling [10]—alongside CXCR6 and IL7R. The gene discussed is DPP4; the disease is COVID-19.