title: Production of prostaglandin E2 in monocytes stimulated in vitro by Chlamydia trachomatis, Chlamydophila pneumoniae, and Mycoplasma fermentans.
abstract: Chlamydia trachomatis (CT) as well as Chlamydophila pneumoniae (CP) cause chronic inflammatory diseases in humans. Persistently infected monocytes are involved in the pathogenesis by inducing mediators of inflammation. An in vitro system of chlamydial persistence in human peripheral blood monocytes (HPBM) was used to investigate prostaglandin E(2) (PGE(2)) production and the expression of the key enzyme for prostaglandin production, cyclooxygenase-2 (COX-2). PGE(2) production was determined by PGE(2)-ELISA of HPBM-culture supernatants. Cox-2 mRNA expression was measured by real-time RT-PCR of total RNA isolated from HPBM. Both, CT and CP, stimulated PGE(2) production of HPBM in vitro. Equivalent numbers of CT per host cell induced a higher PGE(2)-response compared to CP. The amount of synthesized PGE(2) depended on the chlamydial multiplicity of infection (MOI). Even at an MOI of 10 the amount of CT- and CP-induced prostaglandin, respectively, was lower than the amount of prostaglandin induced by E. coli lipopolysaccharide (LPS) at a concentration of 10microg/ml. In contrast to stimulation with LPS, Chlamydia-induced PGE(2) production as well as cox-2 mRNA decreased after day 1 post infection (p.i.). These data indicate that Chlamydia stimulate PGE(2) production in human monocytes. Since Chlamydia are often contaminated by mycoplasma, the influence of mycoplasma on the prostaglandin production was investigated additionally. Mycoplasma fermentans (MF) also stimulated PGE(2) production. The co-infection of mycoplasma and Chlamydia resulted in an additive effect in the production of PGE(2). Thus it is important to use host cells and Chlamydia free of mycoplasma contamination for the analysis of Chlamydia-induced prostaglandin production.
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany. krausse-opatz.birgit@mh-hannover.de
authors.forename: Birgit
authors.initials: B
authors.lastname: Krausse-Opatz
authors.forename: Cornelia
authors.initials: C
authors.lastname: Schmidt
authors.forename: Ursula
authors.initials: U
authors.lastname: Fendrich
authors.forename: Anke
authors.initials: A
authors.lastname: Bialowons
authors.forename: Volkhard
authors.initials: V
authors.lastname: Kaever
authors.forename: Henning
authors.initials: H
authors.lastname: Zeidler
authors.forename: Jens
authors.initials: J
authors.lastname: Kuipers
authors.forename: Lars
authors.initials: L
authors.lastname: Köhler
mesh_terms: D002692:Chlamydia trachomatis / Q000276:immunology*; D016993:Chlamydophila pneumoniae / Q000276:immunology*; D051546:Cyclooxygenase 2; D015232:Dinoprostone / Q000378:metabolism*; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism; D008565:Membrane Proteins; D009000:Monocytes / Q000276:immunology / Q000378:metabolism / Q000382:microbiology*; D016858:Mycoplasma fermentans / Q000276:immunology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism
chemical_list: D007527:Isoenzymes; D008565:Membrane Proteins; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D015232:Dinoprostone