Hydrolyzes a wide range of dipeptides including the conversion of leukotriene D4 to leukotriene E4 (PubMed:2303490, PubMed:31442408, PubMed:32325220, PubMed:6334084). Hydrolyzes cystinyl-bis-glycine (cys-bis-gly) formed during glutathione degradation (PubMed:32325220). Possesses also beta lactamase activity and can hydrolyze the beta-lactam antibiotic imipenem (PubMed:32325220, PubMed:6334084). ; Independently of its dipeptidase activity, acts as an adhesion receptor for neutrophil recruitment from bloodstream into inflamed lungs and liver.