title: Inhibition of epithelial cell apoptosis by Porphyromonas gingivalis.
abstract: Porphyromonas gingivalis is periodontal pathogen that is capable of invading gingival epithelial cells (GECs). Apoptotic responses of primary cultures of GECs to P. gingivalis were investigated with a DNA fragmentation ELISA assay. P. gingivalis induced a transient increase in GEC DNA fragmentation; however, after prolonged incubation GECs did not undergo apoptosis. Furthermore, P. gingivalis blocked apoptosis in GECs following stimulation with camptothecin. Immunoblotting of GECs with Bcl-2 or Bax antibodies showed that P. gingivalis up-regulated Bcl-2 levels in GECs, whereas Bax levels were transiently elevated and declined after 24 h stimulation. Streptococcus gordonii did not affect levels of either molecule. RT-PCR demonstrated that induction of Bcl-2 occurs at the transcriptional level. The results suggest that P. gingivalis can inhibit apoptosis in GECs by up-regulation of the anti-apoptotic molecule Bcl-2. The prevention of host cell apoptosis may represent a strategy for P. gingivalis survival within invaded GECs.
authors: Department of Oral Biology, Box 357132, University of Washington, Seattle, WA 98195, USA.
authors: S F
authors: SF
authors: Nakhjiri
authors: Y
authors: Y
authors: Park
authors: O
authors: O
authors: Yilmaz
authors: W O
authors: WO
authors: Chung
authors: K
authors: K
authors: Watanabe
authors: A
authors: A
authors: El-Sabaeny
authors: K
authors: K
authors: Park
authors: R J
authors: RJ
authors: Lamont
mesh_terms: D017209:Apoptosis; D002478:Cells, Cultured; D004848:Epithelium / Q000378:metabolism / Q000382:microbiology* / Q000473:pathology; D006801:Humans; D016966:Porphyromonas gingivalis / Q000502:physiology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger