IAI FigSearch
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Callegan, M. C.
Right arrow Articles by Gilmore, M. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Callegan, M. C.
Right arrow Articles by Gilmore, M. S.

 Previous Article  |  Next Article 

Infection and Immunity, July 1999, p. 3357-3366, Vol. 67, No. 7
0019-9567/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.

Role of Hemolysin BL in the Pathogenesis of Extraintestinal Bacillus cereus Infection Assessed in an Endophthalmitis Model

Michelle C. Callegan,1,2 Bradley D. Jett,1,2,dagger Lynn E. Hancock,3 and Michael S. Gilmore1,2,3,*

Department of Ophthalmology,1 Department of Microbiology and Immunology,3 and Molecular Pathogenesis of Eye Infections Research Center, Dean A. McGee Eye Institute,2 University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma

Received 21 December 1998/Returned for modification 3 February 1999/Accepted 12 April 1999

Bacillus cereus is a rare cause of serious human infection but, paradoxically, causes one of the most severe posttraumatic or endogenous infections of the eye, endophthalmitis, which frequently results in blindness. The virulence of B. cereus endophthalmitis historically has been attributed to toxin production. We therefore sought to examine the contribution of the dermonecrotic toxin, hemolysin BL, to the pathogenesis of B. cereus infection in an endophthalmitis system that is highly amenable to study. The pathogenesis of infection resulting from intravitreal injection of 102 CFU of either a clinical ocular isolate of B. cereus producing hemolysin BL (HBL+) or an isogenic mutant in this trait (HBL-) was assessed bacteriologically and by slit lamp biomicroscopy, electroretinography, histology, and inflammatory cell enumeration. Both HBL+ and HBL- strains evoked severe intraocular inflammatory responses as early as 12 h postinfection, with complete loss of retinal responsiveness by 12 h. The infections caused by both strains spread of the infection to adjacent tissues by 18 h. No significant differences in intraocular bacterial growth (P >=  0.21) or inflammatory changes (P >=  0.21) were observed in eyes infected with either HBL+ or HBL- strains during the course of infection. The level of retinal responsiveness was greater in HBL- infected eyes than in HBL+-infected eyes at 6 h only (P = 0.01). These results indicate that hemolysin BL makes no essential contribution to the severe and rapid course of infection in the endophthalmitis model.

* Corresponding author. Mailing address: Department of Ophthalmology, University of Oklahoma Health Sciences Center, 608 Stanton L. Young Blvd., Oklahoma City, OK 73104. Phone: (405) 271-1084. Fax: (405) 271-8128. E-mail: mgilmore{at}aardvark.ou.edu.

dagger Present address: Department of Biology, Oklahoma Baptist University, Shawnee, Okla.

Infection and Immunity, July 1999, p. 3357-3366, Vol. 67, No. 7
0019-9567/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. J. Virol. Eukaryot. Cell
Microbiol. Mol. Biol. Rev. Clin. Vaccine Immunol. All ASM Journals

Copyright © 1999 by the American Society for Microbiology. All rights reserved.