Contribution of pneumolysin and autolysin to the pathogenesis of experimental pneumococcal endophthalmitis
| Autor: | J Ricardo Costa, Eugene W.M. Ng, Donald J. D'Amico, Nasrollah Samiy, Kathryn L. Ruoff, Felecia V Cousins, Edward Connolly |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Male
Virulence medicine.disease_cause Eye Infections Bacterial Pneumococcal Infections Microbiology Pathogenesis Endophthalmitis Bacterial Proteins Streptococcus pneumoniae medicine Animals Pneumolysin business.industry Cytotoxins Autolysin General Medicine N-Acetylmuramoyl-L-alanine Amidase Eye infection medicine.disease Rats Ophthalmology Rats Inbred Lew Intraocular Infection Streptolysins business |
| Zdroj: | Retina (Philadelphia, Pa.). 22(5) |
| ISSN: | 0275-004X |
| Popis: | Purpose To determine the contribution of pneumolysin and autolysin, two putative pneumococcal virulence proteins, to the pathogenesis of Streptococcus pneumoniae endophthalmitis. Methods Endophthalmitis was established in Lewis rats by intravitreal injection of pneumococcal strains at an inoculum of 10 organisms. The virulence of three closely related type 2 S. pneumoniae strains were compared: a pneumolysin-deficient derivative (PLN-A), an autolysin-deficient derivative (AL-6), and their isogenic wild-type parent (D 39). Clinical and histologic inflammation scores were compared 24 hours and 48 hours after inoculation. Results Eyes infected with PLN-A and AL-6 strains showed less anterior segment inflammation clinically at 24 hours than did eyes infected with the wild-type strain. Histologic examination at 24 hours showed significantly less corneal infiltration and vitritis and more relative preservation of retinal tissue in eyes infected with PLN-A and AL-6 strains than in eyes infected with the wild-type strain. At 48 hours, no observable differences between PLN-A and wild-type strains were present clinically or histologically. Histologically, however, the AL-6 strain caused less retinal damage than did the wild-type strain. Conclusions Intraocular infection with pneumolysin-deficient S. pneumoniae results in less severe tissue damage in the first 24 hours of disease compared with infection with pneumolysin-producing S. pneumoniae. Autolysin-deficient S. pneumoniae shows a similar degree of attenuated virulence. Pneumolysin and autolysin may contribute to the early pathogenesis of pneumococcal endophthalmitis. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|