Analysis of Photoreceptor Rod Outer Segment Phagocytosis by RPE Cells In Situ

  • Saumil Sethna
  • Silvia C. Finnemann
Part of the Methods in Molecular Biology book series (MIMB, volume 935)


Counting rhodopsin-positive phagosomes residing in the retinal pigment epithelium (RPE) in the eye at different times of day allows a quantitative assessment of engulfment and digestion phases of diurnal RPE phagocytosis, which efficiently clears shed photoreceptor outer segment fragments (POS) from the neural retina. Comparing such activities among age- and background-matched experimental wild-type and mutant mice or rats serves to identify roles for specific proteins in the phagocytic process. Here, we describe experimental procedures for mouse eye harvest, embedding, sectioning, immunofluorescence labeling of rod POS phagosomes in RPE cells in sagittal eye sections, imaging of POS phagosomes in the RPE by laser scanning confocal microscopy, and POS quantification.

Key words

Mouse eye Retina Retinal pigment epithelium Diurnal photoreceptor outer segment phagocytosis Rhodopsin-positive phagosome quantification Immunofluorescence microscopy Paraffin sectioning 



This work was supported by NIH grant EY013295.


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Department of Biological SciencesFordham UniversityBronxUSA
  2. 2.Department of Biological Sciences, Larkin HallFordham UniversityBronxUSA

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