title: Tumor necrosis factor alpha and prostaglandin E2 production by human monocyte-derived macrophages infected with spotted fever group rickettsiae.
abstract: Infection of macrophages by intracellular parasites might modulate production of tumor necrosis factor (TNF) and prostaglandin E2 (PGE2), which, in turn, might have a profound effect on the outcome of the infection in vivo. In this study we examined in an in vitro system, the rickettsial yield in human monocyte-derived macrophages (MdM) and the PGE2 and TNF production by MdM infected with Rickettsia conorii RC, Casablanca strain) or Israeli spotted fever (ISF, G-212 strain). TNF and PGE2 were determined in the media of MdM infected with RC or ISF. TNF reached maximum levels 24 h post-infection and then declined, while PGE2 levels increased continuously during the infection up to 96 h post-infection. Addition of dexamethasone inhibited both TNF and PGE2 production and enhanced rickettsial yield in MdM. Inhibition of PGE2 production by indomethacin resulted in increased production of TNF from rickettsial-infected MdM, while addition of PGE2 caused partial inhibition of TNF production from infected MdM.
authors.affiliation: Virology Unit, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel.
authors.forename: E
authors.initials: E
authors.lastname: Manor
authors.forename: I
authors.initials: I
authors.lastname: Sarov
mesh_terms: D003907:Dexamethasone / Q000494:pharmacology; D015232:Dinoprostone / Q000096:biosynthesis*; D006801:Humans; D008264:Macrophages / Q000378:metabolism* / Q000382:microbiology; D009000:Monocytes / Q000378:metabolism; D012282:Rickettsia Infections / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
chemical_list: D014409:Tumor Necrosis Factor-alpha; D003907:Dexamethasone; D015232:Dinoprostone