|
|||||
|
|
Treatment of HeLa cells with bacterial water extracts inhibits Shigella flexneri invasion |
|
| Authors: | Bonny Breckinridge DiNovo Richard Doan Roy B Dyer Samuel Baron Norbert K Herzog David W Niesel |
| Institution: | Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, TX 77555-1019, USA;Department of Pathology, The University of Texas Medical Branch, Galveston, TX 77555-0609, USA;The WHO Collaborating Center for Tropical Diseases, The University of Texas Medical Branch, Galveston, TX 77555-0609, USA |
| Abstract: | Abstract Pathogenesis mediated by Shigella flexneri requires invasion of the gastrointestinal epithelium. It has been previously shown that HeLa cells challenged with S. flexneri show alterations in their phosphotyrosine-containing protein profile. In this report, we demonstrated that bacterial water extracts (WE) abrogated the invasion of HeLa cells by S. flexneri in a dose-dependent manner. A proteinaceous component of S. flexneri was shown to be responsible for this inhibitory activity. Proteins encoded on the 140-MDa plasmid were not responsible for the observed inhibition. WE from other Gram-negative bacteria also inhibited Shigella invasion of HeLa cells. HeLa cells pretreated with WE showed changes in the profile and the intensity of phosphotyrosine-containing protein bands. These data were consistent with a surface protein component in WE which initiated aberrant host cell signaling at the membrane which may account for the inhibition of bacterial entry. |
| Keywords: | Shigella flexneri Cellular invasion Cell signaling |