title: Monitoring of strain-dependent responsiveness to TLR activation in the mouse anterior segment using SD-OCT.
abstract: OBJECTIVE
  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.affiliation: Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Laura Elizabeth
authors.initials: LE
authors.lastname: Downie
authors.affiliation: Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Matthew James
authors.initials: MJ
authors.lastname: Stainer
authors.affiliation: Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Holly Rose
authors.initials: HR
authors.lastname: Chinnery
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000867:Anterior Chamber / Q000166:cytology; D000869:Anterior Eye Segment / Q000187:drug effects* / Q000473:pathology; D015715:Corneal Edema / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology; D003319:Corneal Stroma / Q000473:pathology; D004195:Disease Models, Animal; D005260:Female; D008070:Lipopolysaccharides / Q000494:pharmacology; D008137:Longitudinal Studies; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009838:Oligodeoxyribonucleotides / Q000494:pharmacology; D051197:Toll-Like Receptor 4 / Q000502:physiology*; D051217:Toll-Like Receptor 9 / Q000502:physiology*; D041623:Tomography, Optical Coherence
chemical_list: C408982:CPG-oligonucleotide; D008070:Lipopolysaccharides; D009838:Oligodeoxyribonucleotides; D051197:Toll-Like Receptor 4; D051217:Toll-Like Receptor 9
keywords: SD-OCT; cornea; imaging; inflammation; toll-like receptors