|
|
||||||||
1From the Departments of Ophthalmology and 2Microbiology and Immunology, University of Oklahoma Health Sciences Center, Dean A. McGee Eye Institute, Oklahoma City, Oklahoma; and 3Dipartimento di Patologia Sperimentale, Biotecnologie Mediche, Infettivologia ed Epidemiologia, Universitá di Pisa, Pisa, Italy.
PURPOSE. Bacillus cereus causes one of the most rapidly blinding forms of bacterial endophthalmitis. Migration of B. cereus throughout the eye during endophthalmitis is a unique aspect of this disease that may contribute to intraocular virulence. This study was conducted to analyze the contribution of swarming and intraocular migration to the pathogenesis of experimental endophthalmitis.
METHODS. Eyes were injected intravitreally with 100 colony-forming units (CFU) of either wild-type, nonswarming, or swarming-complemented strains of B. cereus. Pathogenicity was compared throughout the course of infection by biomicroscopy, histology, electroretinography, and bacterial and inflammatory cell quantitation.
RESULTS. Wild-type, nonswarming, and swarming-complemented B. cereus strains grew to a similar number in the vitreous throughout the course of infection. Unlike the wild-type and swarming-complemented strains, the nonswarming mutant did not migrate to the anterior segment during infection. The rate of decrease in retinal responses of eyes infected with the all strains was similar, resulting in near complete elimination of retinal function by 12 hours. All Bacillus strains caused similar degrees of posterior segment inflammation and retinal destruction. However, the accumulation of inflammatory cells in the anterior chamber, hyphemae, and corneal ring abscesses did not occur in eyes infected with the nonswarming mutant.
CONCLUSIONS. The deficiency in swarming had little effect on retinal function loss or the overall course or severity of experimental B. cereus endophthalmitis. However, a deficiency in swarming prevented Bacillus from migrating to the anterior segment, leading to less severe anterior segment disease.
This article has been cited by other articles:
![]() |
S. Salvetti, E. Ghelardi, F. Celandroni, M. Ceragioli, F. Giannessi, and S. Senesi FlhF, a signal recognition particle-like GTPase, is involved in the regulation of flagellar arrangement, motility behaviour and protein secretion in Bacillus cereus Microbiology, August 1, 2007; 153(8): 2541 - 2552. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Ghelardi, F. Celandroni, S. Salvetti, M. Ceragioli, D. J. Beecher, S. Senesi, and A. C. L. Wong Swarming Behavior of and Hemolysin BL Secretion by Bacillus cereus Appl. Envir. Microbiol., June 15, 2007; 73(12): 4089 - 4093. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |