April 2014
Volume 55, Issue 13
Free
ARVO Annual Meeting Abstract  |   April 2014
Genetic model system for microglia depletion in the adult mouse retina
Author Affiliations & Notes
  • Lian Zhao
    Unit on Neuron-Glia Interactions in Retinal Disease, National Eye Institute, Bethesda, MD
  • Xu Wang
    Unit on Neuron-Glia Interactions in Retinal Disease, National Eye Institute, Bethesda, MD
  • Christopher Parkhurst
    Department of Physiology and Neuroscience, New York University School of Medicine, New York, NY
  • Wen-biao Gan
    Department of Physiology and Neuroscience, New York University School of Medicine, New York, NY
  • Robert N Fariss
    Biological Imaging Core, National Eye Institute, Bethesda, MD
  • Wai T Wong
    Unit on Neuron-Glia Interactions in Retinal Disease, National Eye Institute, Bethesda, MD
Investigative Ophthalmology & Visual Science April 2014, Vol.55, 2265. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Lian Zhao, Xu Wang, Christopher Parkhurst, Wen-biao Gan, Robert N Fariss, Wai T Wong; Genetic model system for microglia depletion in the adult mouse retina. Invest. Ophthalmol. Vis. Sci. 2014;55(13):2265.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose: Microglia have been implicated as a contributing factor to retinal disease in humans and animal models. However, endogenous functions of microglia in the healthy adult retina have not yet been well-defined. We describe the use of a genetic model system for depleting microglia in the retina that can be used to study the constitutive contributions of retinal microglia to retinal function.

Methods: Transgenic mice on a C57Bl6 background in which the Cx3cr1 gene was replaced by a sequence encoding a mutant Cre protein with a tamoxifen (TAM)-dependent estrogen ligand-binding domain (Cx3cr1CreER) were crossed with mice carrying lox-P-flanked (‘floxed’) diphtheria toxin (DTA) to create Cx3cr1CreER/+DTA+/-(TG) mice. TG mice were gavaged with TAM (500mg/kg) at different time intervals and the density and distribution of retinal microglia analyzed.

Results: Histological comparisons of retinas from young adult (6-12 weeks old) wild type C57Bl6 mice (WT) and control TG mice (not treated with TAM) demonstrated similarities with respect to: 1) retinal anatomy (lamination and thickness of retinal layers), and 2) retinal microglia (distribution, density and morphology). Following gavage with TAM (2 cycles, 2 days apart), near-complete depletion of microglia in all retinal locations and layers was achieved 2 days post-gavage (DPG) as evidenced by Iba1 and CD11b immunohistochemical analyses. Beginning at around 9 DPG, isolated Iba1+ cells with amoeboid to ramified morphologies appeared in the IPL in the peripapillary retinal, spreading into the equatorial retina by 16 DPG. Colonization of the retina from central to the peripheral retina was relatively complete by 30 DPG. Near-complete microglia depletion in the retina was sustained for up to 30 days by repeated TAM gavage, maintaining total retinal microglia densities at ≈0.5% of that in control TG retina.

Conclusions: In the absence of TAM exposure, TG mice demonstrated normal retinal anatomy and retinal microglial distribution, but become highly depleted of microglia following a brief period of TAM exposure. Sustained and near-complete depletion up to 30 days can be induced by maintaining TAM exposure. This genetic system demonstrates utility in studies aimed at studying the contributions of microglia to retinal structure, physiology, and disease.

Keywords: 595 microglia  
×
×

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.

×