Biogenesis of Multilamellar Membrane Incorporations (Myeloid Bodies) in the Eolagurus Luteus Pigmented Epithelium

The study detected common ultrastructure of pigmented epithelium cells of Eolagurus luteus and other mammals and described its features characteristic of this species. Stages of interactions between the pigmented epithelium cells and external segments of retinal rod cells were studied. Migration of the external segments to the apical zone of a pigmented epithelium cell was observed. A pigmented epithelium cell was characterized by the presence of tubular endoplasmic reticulum and electron dense cytoplasm with processes directed to the retina. Multilamellar formations were detected, regarded as the initial stages of the myeloid body formation. These structures were characterized by periodicity of layers of ~4.2 and ~13.3 nm. The periodicity of layers in the formed myeloid body was ~23 nm. Interactions between the external segments and cells of pigmented epithelium, leading to formation of myeloid bodies, and the signifi cance of this process for normal work of retinal elements are discussed.