LTA4H (Leukotriene A4-hydrolase ) is a Zn2+-containing enzyme with both epoxide hydrolase and aminopeptidase activity. As an epoxide hydrolase, LTA4H catalyzes the hydration of LTA4 to leukotriene B4 (LTB4, 5S,12R-dihydroxy-6,14-cis-8,10-trans-eicosatetraenoic acid), a potent lipid chemoattractant that influences inflammation, immune responses, and host defense against infection. As an aminopeptidase, LTA4H catalyzes the cleavage of amides of para-nitroaniline. The human LTA4H gene encodes a 610 amino acid protein.