| First Author | Talreja D | Year | 2015 |
| Journal | Invest Ophthalmol Vis Sci | Volume | 56 |
| Issue | 3 | Pages | 1719-32 |
| PubMed ID | 25678692 | Mgi Jnum | J:230974 |
| Mgi Id | MGI:5766605 | Doi | 10.1167/iovs.14-16087 |
| Citation | Talreja D, et al. (2015) In Vivo Role of TLR2 and MyD88 Signaling in Eliciting Innate Immune Responses in Staphylococcal Endophthalmitis. Invest Ophthalmol Vis Sci 56(3):1719-32 |
| abstractText | PURPOSE: The purpose of this study was to investigate the protective mechanisms evoked by TLR2 and MyD88 signaling in bacterial endophthalmitis in vivo. METHODS: Endophthalmitis was induced in wild-type (WT), TLR2(-/-), MyD88(-/-), and Cnlp(-/-) mice by intravitreal injections of a laboratory strain (RN6390) and two endophthalmitis isolates of Staphylococcus aureus. Disease progression was monitored by assessing corneal and vitreous haze, bacterial burden, and retinal tissue damage. Levels of inflammatory cytokines/chemokines were determined using quantitative RT-PCR (qRT-PCR) and ELISA. Flow cytometry was used to assess neutrophil infiltration. Cathelicidin-related antimicrobial peptide (CRAMP) expression was determined by immunostaining and dot blot. RESULTS: Eyes infected with either laboratory or clinical isolates exhibited higher levels of inflammatory mediators at the early stages of infection (</=24 hours) in WT mice than in TLR2(-/-) or MyD88(-/-) mice. However, their levels surpassed that of WT mice at the later stages of infection (>48 hours), coinciding with increased bacterial burden and retinal damage. Both TLR2(-/-) and MyD88(-/-) retinas produced reduced levels of CRAMP, and its deficiency (Cnlp(-/-)) rendered the mice susceptible to increased bacterial burden and retinal tissue damage as early as 1 day post infection. Analyses of inflammatory mediators and neutrophil levels in WT versus Cnlp(-/-) mice showed a trend similar to that observed in TLR2 and MyD88 KO mice. Furthermore, we observed that even a 10-fold lower infective dose of S. aureus was sufficient to cause endophthalmitis in TLR2(-/-) and MyD88(-/-) mice. CONCLUSIONS: TLR2 and MyD88 signaling plays an important role in protecting the retina from staphylococcal endophthalmitis by production of the antimicrobial peptide CRAMP. |
