Human cytomegalovirus circumvents NF-kappa B dependence in retinal pigment epithelial cells.
The human CMV (HCMV) is a persistent virus that may cause severe inflammatory responses especially in immunocompromised hosts. In different cell types, HCMV infection leads to the activation of the pleiotropic transcription factor, NF-kappaB, which triggers virus replication but also propagates cell-mediated inflammatory mechanisms that largely depend on PG synthesis. We investigated the interactions of HCMV and the NF-kappaB-dependent PG synthesis pathway in cultures of retinal pigment epithelial (RPE) cells that are known to be infected in HCMV retinitis patients. Unlike in other cell types, HCMV increased neither NF-kappaB activity nor p65 and p105/50 mRNA levels in RPE cells. Both TNF-alpha and phorbol ester 12,0-tetradecanoylphorbol 13-acetate (TPA) enhanced NF-kappaB activity but only TPA increased HCMV replication. Cyclooxygenase-2 expression and PGE2 release was increased by TPA and TNF-alpha but not by HCMV infection. Stimulatory activity of TPA on HCMV replication was suppressed by protein kinase C inhibitors and inhibitors of p42/44 and p38 mitogen-activated protein kinases but not by NF-kappaB inhibitors. In conclusion, HCMV circumvents the NF-kappaB route in favor of the protein kinase C-dependent mitogen-activated protein kinase pathway in RPE cells. This virus/host cell interaction might be a mechanism that promotes HCMV persistence in immune-privileged organs such as the eye.
Cinatl
J
J
Zentrum der Hygiene, Institut für Medizinische Virologie, Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany. cinatl@em.uni-frankfurt.de
Margraf
S
S
Vogel
J U
JU
Scholz
M
M
Cinatl
J
J
Doerr
H W
HW
D002478:Cells, Cultured; D051546:Cyclooxygenase 2; D003587:Cytomegalovirus / Q000187:drug effects / Q000502:physiology*; D015232:Dinoprostone / Q000378:metabolism; D006801:Humans; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics; D008565:Membrane Proteins; D020928:Mitogen-Activated Protein Kinases / Q000502:physiology; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D052002:NF-kappa B p50 Subunit; D010857:Pigment Epithelium of Eye / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism* / Q000821:virology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis / Q000235:genetics; D011493:Protein Kinase C / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D051996:Transcription Factor RelA; D014158:Transcription, Genetic; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D015854:Up-Regulation; D014779:Virus Replication / Q000187:drug effects
D007527:Isoenzymes; D008565:Membrane Proteins; D016328:NF-kappa B; D052002:NF-kappa B p50 Subunit; D012333:RNA, Messenger; D051996:Transcription Factor RelA; D014409:Tumor Necrosis Factor-alpha; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D011493:Protein Kinase C; D020928:Mitogen-Activated Protein Kinases; D015232:Dinoprostone; D013755:Tetradecanoylphorbol Acetate