Clustering and shared upregulation of glycolytic enzyme encoding genes GALM, GAPDH, GPI, and ALDOA together with HIF1A, and transcripts regulating exhaustion (TIGIT and LAG3) (Fig. 7b) suggested that hypoxia/anaerobic axis is associated with impaired CD8+TM function in COVID-19 BALF. This evidence concerns the gene HIF1A and COVID-19.