September 2016
Volume 57, Issue 12
Open Access
ARVO Annual Meeting Abstract  |   September 2016
Ocular inflammatory cell infiltrates and angiogenesis are augmented by administration of the toll-like receptor-2 (TLR-2) ligand in a mouse model of choroidal neovascularization (CNV)
Author Affiliations & Notes
  • Stephen H Poor
    Novartis, Cambridge, Massachusetts, United States
  • Yubin Qiu
    Novartis, Cambridge, Massachusetts, United States
  • Adrian Will-Orrego
    Novartis, Cambridge, Massachusetts, United States
  • Elizabeth Fassbender
    Novartis, Cambridge, Massachusetts, United States
  • Siyuan Shen
    Novartis, Cambridge, Massachusetts, United States
  • Maura Crowley
    Novartis, Cambridge, Massachusetts, United States
  • Sha-Mei Liao
    Novartis, Cambridge, Massachusetts, United States
  • Bruce D Jaffee
    Novartis, Cambridge, Massachusetts, United States
  • Footnotes
    Commercial Relationships   Stephen Poor, Noavartis (E); Yubin Qiu, Novartis (E); Adrian Will-Orrego, Novartis (E); Elizabeth Fassbender, Novartis (E); Siyuan Shen, Novartis (E); Maura Crowley, Novartis (E); Sha-Mei Liao, Novartis (E); Bruce Jaffee, Novartis (E)
  • Footnotes
    Support  None
Investigative Ophthalmology & Visual Science September 2016, Vol.57, 484. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to Subscribers Only
      Sign In or Create an Account ×
    • Get Citation

      Stephen H Poor, Yubin Qiu, Adrian Will-Orrego, Elizabeth Fassbender, Siyuan Shen, Maura Crowley, Sha-Mei Liao, Bruce D Jaffee; Ocular inflammatory cell infiltrates and angiogenesis are augmented by administration of the toll-like receptor-2 (TLR-2) ligand in a mouse model of choroidal neovascularization (CNV). Invest. Ophthalmol. Vis. Sci. 2016;57(12):484.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose : Modified lipids and proteins present in AMD tissues might activate innate immune system including toll-like receptors. Our study investigates the effect of TLR-2 activation on ocular inflammation and angiogenesis in a murine laser-induced CNV model.

Methods : PAM3CSK4 (PAM) is a synthetic lipopeptide mimicking bacterial cell walls, activating TLR-2. Single i.p. injections of 50 µg of PAM (a dose previously identified to optimally induce retinal cytokine production) were administered at either day -1, 0, 1, 2, 3, or 4 relative to laser application. Laser pulses were applied to mice eyes and CNV area measured 7 days later by i.v. injection of a vascular label, flat mount imaging, and quantification of CNV area by morphometric analysis. There were 3 laser pulses per eye and 10 mice per group, yielding 60 data points per condition. Mice challenged with PAM or saline were also administered systemic VEGF antibodies (“4G3” at 3 mg/kg dosed 3x per week i.p.).
To study cellular infiltration, labeled antibodies were used to identify neutrophils and microglia (GR-1 and Iba-1) at day 3 and 7 after laser in the RPE-choroid complex. Images were captured with a single fluorescent microscope with consistent exposure times on the same day for each experiment. Intensity of CNV label was assessed in MatLab. To confirm PAM’s mechanism of action, CNV area was assessed in sex matched TLR-2 KO and wild-type litter-mate controls.

Results : Single i.p. injections of PAM increased CNV area with the largest effect at 2 days after laser increasing CNV area by an average of 67% (+/- 18%, p ≤ 0.003, n = 4 independent studies) compared to mice injected with saline. . I.p. injections of PAM increased neutrophil and microglia cell intensity in the CNV lesion by 480% and 89% on day 3 compared to mice injected with PBS. Minimal differences in antibody label intensity were observed in day 7 tissues. CNV area was similar in both WT and TLR-2 KO mice injected with PBS. PAM increased CNV area in WT mice, but not in the TLR-2 KO mice. Anti-VEGF Ab administration reduces laser-induced CNV area 62% (p < 0.0001 vs vehicle) in mice challenged with PAM i.p. injections 2 days after laser.

Conclusions : PAM injection increases ocular inflammation and exacerbates ocular angiogenesis by a TLR-2 dependent mechanism that is also sensitive to VEGF inhibition.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×