title: Post-exposure therapeutic efficacy of COX-2 inhibition against Burkholderia pseudomallei.
abstract: Burkholderia pseudomallei is a Gram-negative, facultative intracellular bacillus and the etiologic agent of melioidosis, a severe disease in Southeast Asia and Northern Australia. Like other multidrug-resistant pathogens, the inherent antibiotic resistance of B. pseudomallei impedes treatment and highlights the need for alternative therapeutic strategies that can circumvent antimicrobial resistance mechanisms. In this work, we demonstrate that host prostaglandin E2 (PGE2) production plays a regulatory role in the pathogenesis of B. pseudomallei. PGE2 promotes B. pseudomallei intracellular survival within macrophages and bacterial virulence in a mouse model of pneumonic melioidosis. PGE2-mediated immunosuppression of macrophage bactericidal effector functions is associated with increased arginase 2 (Arg2) expression and decreased nitric oxide (NO) production. Treatment with a commercially-available COX-2 inhibitor suppresses the growth of B. pseudomallei in macrophages and affords significant protection against rapidly lethal pneumonic melioidosis when administered post-exposure to B. pseudomallei-infected mice. COX-2 inhibition may represent a novel immunotherapeutic strategy to control infection with B. pseudomallei and other intracellular pathogens.
authors.affiliation: Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America.
authors.forename: Saja
authors.initials: S
authors.lastname: Asakrah
authors.forename: Wildaliz
authors.initials: W
authors.lastname: Nieves
authors.forename: Zaid
authors.initials: Z
authors.lastname: Mahdi
authors.forename: Mallory
authors.initials: M
authors.lastname: Agard
authors.forename: Arnold H
authors.initials: AH
authors.lastname: Zea
authors.forename: Chad J
authors.initials: CJ
authors.lastname: Roy
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Morici
mesh_terms: D000818:Animals; D016957:Burkholderia pseudomallei / Q000276:immunology*; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D052246:Cyclooxygenase 2 Inhibitors / Q000008:administration & dosage*; D004195:Disease Models, Animal; D005260:Female; D008264:Macrophages / Q000201:enzymology / Q000276:immunology / Q000382:microbiology; D008554:Melioidosis / Q000188:drug therapy* / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D011014:Pneumonia / Q000188:drug therapy* / Q000382:microbiology; D016896:Treatment Outcome
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2