DPEP1 (dipeptidase 1) is a multifunctional protein with critical roles in inflammation and disease pathogenesis. Primary function: DPEP1 serves as a neutrophil adhesion receptor on endothelial cells of lungs, liver, and kidneys, independent of its enzymatic activity 1, 2. Mechanism: DPEP1 mediates leukocyte recruitment through CD44-dependent interactions 2 and regulates glutathione metabolism through leukotriene D4 catabolism 3, 4. Disease relevance: DPEP1 is upregulated in microsatellite-stable colorectal cancer (MSS-CRC), where it promotes immune exclusion by recruiting neutrophils that suppress CD8+ T cell infiltration 5, 6. DPEP1 variants regulate food allergen absorption in the intestine, modulating anaphylaxis susceptibility 3. Clinical significance: DPEP1 inhibition via cilastatin or antagonistic peptides reduces acute kidney injury from ischemia-reperfusion injury 2 and decreases neutrophil-driven lung inflammation 1. DPEP1 serves as a fibroblast marker in cardiovascular disease 7 and is a potential therapeutic target for colorectal cancer immunotherapy and food allergy management.