Our findings that DDR1 is upregulated in the renal cortices of mice subjected to severe AKI; it is expressed by proximal tubule cells in vitro (present paper and ref. 11); and it is upregulated in proximal tubules in patients with AKI who received a kidney transplant (11) as well as in mice subjected to AKI (present paper), clearly suggest that DDR1 expression on proximal tubule cells contributes to disease. Here, DDR1 is linked to acute kidney injury.