Monitoring of strain-dependent responsiveness to TLR activation in the mouse anterior segment using SD-OCT.

Abstract

PURPOSE:

To determine whether spectral-domain optical coherence tomography (SD-OCT) can be used to longitudinally monitor inflammation in the mouse anterior segment and to identify any strain-dependent differences in responsiveness to distinct toll-like receptor (TLR) ligands.

METHODS:

Corneal inflammation was induced in BALB/c and C57BL/6 mice following central corneal abrasions and topical application of saline, TLR-4 ligand, lipopolysaccharide (LPS), or TLR-9 ligand, CpG-oligodeoxynucleotide (CpG-ODN; CpG). Anterior-segment images were captured using SD-OCT at baseline, 24 hours, and 1 week post treatment. Corneal thickness, stromal haze, and the number of keratic precipitates (KP) and anterior chamber (AC) cells were longitudinally compared to determine differences between mouse strains, time points, and TLR activation.

RESULTS:

In both mouse strains, treatment with CpG, but not saline or LPS, resulted in a similar number of KPs and AC cells. In C57BL/6 mice, central corneal thickness (CCT) increased in CpG- and LPS-treated eyes at 24 hours, which normalized by 1 week. In BALB/c mice, a significant increase in CCT occurred in eyes treated with CpG at 1 week. Stromal haze peaked in C57BL/6 eyes treated with LPS- or CPG-treatment at 24 hours; however, BALB/c eyes showed persistent and marked increases in corneal haze compared with baseline at 1 week post treatment.

CONCLUSIONS:

Spectral-domain OCT enables high-resolution, longitudinal, in vivo imaging of anterior segment inflammation in mice and revealed novel strain- and time-dependent differences in response to distinct TLR activation in the cornea.

• Authors: Laura Elizabeth Downie, Matthew James Stainer, Holly Rose Chinnery
• Journal: Investigative ophthalmology & visual science (Invest Ophthalmol Vis Sci) Vol. 55 Issue 12 Pg. 8189-99 (Nov 20 2014) ISSN: 1552-5783 [Electronic] United States
• PMID: 25414189 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Chemical References

• CPG-oligonucleotide
• Lipopolysaccharides
• Oligodeoxyribonucleotides
• Toll-Like Receptor 4
• Toll-Like Receptor 9

Topics

• Analysis of Variance
• Animals
• Anterior Chamber (cytology)
• Anterior Eye Segment (drug effects, pathology)
• Corneal Edema (diagnosis, drug therapy, pathology)
• Corneal Stroma (pathology)
• Disease Models, Animal
• Female
• Lipopolysaccharides (pharmacology)
• Longitudinal Studies
• Mice
• Mice, Inbred BALB C
• Mice, Inbred C57BL
• Oligodeoxyribonucleotides (pharmacology)
• Toll-Like Receptor 4 (physiology)
• Toll-Like Receptor 9 (physiology)
• Tomography, Optical Coherence