The enzyme 15-hydroxy prostaglandin dehydrogenase (15-PGDH) initiates the catabolism of PGs and related eicosanoids. SW033291 is a potent inhibitor of 15-PGDH (Ki = ~0.1 nM) that has activity in vivo. It rapidly increases the levels of PGE2 in bone marrow and other tissues in mice after intraperitoneal injection. SW033291 accelerates hematopoietic recovery in mice receiving bone marrow transplant and promotes tissue regeneration in mouse models of colon and liver injury.