Histochemistry and Cell Biology

, Volume 142, Issue 6, pp 601–617 | Cite as

Characterization of dsRed2-positive cells in the doublecortin-dsRed2 transgenic adult rat retina

  • A. Trost
  • F. Schroedl
  • J. Marschallinger
  • F. J. Rivera
  • B. Bogner
  • C. Runge
  • S. Couillard-Despres
  • L. Aigner
  • H. A. Reitsamer
Original Paper


Doublecortin (DCX) is predominantly expressed in neuronal precursor cells and young immature neurons of the developing and adult brain, where it is involved in neuronal differentiation, migration and plasticity. Moreover, its expression pattern reflects neurogenesis, and transgenic DCX promoter-driven reporter models have been previously used to investigate adult neurogenesis. In this study, we characterize dsRed2 reporter protein-expressing cells in the adult retina of the transgenic DCX promoter-dsRed2 rat model, with the aim to identify cells with putative neurogenic activity. Additionally, we confirmed the expression of the dsRed2 protein in DCX-expressing cells in the adult hippocampal dentate gyrus. Adult DCX-dsRed2 rat retinas were analyzed by immunohistochemistry for expression of DCX, NF200, Brn3a, Sox2, NeuN, calbindin, calretinin, PKC-a, Otx2, ChAT, PSA-NCAM and the glial markers GFAP and CRALBP, followed by confocal laser-scanning microscopy. In addition, brain sections of transgenic rats were analyzed for dsRed2 expression and co-localization with DCX, NeuN, GFAP and Sox2 in the cortex and dentate gyrus. Endogenous DCX expression in the adult retina was confined to horizontal cells, and these cells co-expressed the DCX promoter-driven dsRed2 reporter protein. In addition, we encountered dsRed2 expression in various other cell types in the retina: retinal ganglion cells (RGCs), a subpopulation of amacrine cells, a minority of bipolar cells and in perivascular cells. Since also RGCs expressed dsRed2, the DCX-dsRed2 rat model might offer a useful tool to study RGCs in vivo under various conditions. Müller glial cells, which have previously been identified as cells with stem cell features and with neurogenic potential, did express neither endogenous DCX nor the dsRed2 reporter. However, and surprisingly, we identified a perivascular glial cell type expressing the dsRed2 reporter, enmeshed with the glia/stem cell marker GFAP and colocalizing with the neural stem cell marker Sox2. These findings suggest the so far undiscovered existence of perivascular associated cell with neural stem cell-like properties in the adult retina.


Doublecortin Retina Retinal ganglion cells Perivascular cells Dentate gyrus Cortex 





Inner nuclear layer


Inner plexiform layer


Ganglion cell layer


Retinal ganglion cells



The work was supported by Adele Rabensteiner Foundation, Fuchs-Foundation, Lotte Schwarz Endowment for Experimental Ophthalmology and Glaucoma Research, PMU-FFF (R-10/03/016-TRO) and FWF (FWF-P15729).


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • A. Trost
    • 1
    • 3
  • F. Schroedl
    • 1
    • 2
  • J. Marschallinger
    • 3
    • 5
  • F. J. Rivera
    • 3
    • 5
  • B. Bogner
    • 1
  • C. Runge
    • 1
  • S. Couillard-Despres
    • 4
    • 5
  • L. Aigner
    • 3
    • 5
  • H. A. Reitsamer
    • 1
  1. 1.Ophthalmology/OptometryParacelsus Medical UniversitySalzburgAustria
  2. 2.AnatomyParacelsus Medical UniversitySalzburgAustria
  3. 3.Molecular Regenerative MedicineParacelsus Medical UniversitySalzburgAustria
  4. 4.Institute of Experimental NeuroregenerationParacelsus Medical UniversitySalzburgAustria
  5. 5.Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS)Paracelsus Medical UniversitySalzburgAustria

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