Organotypic culture system of chicken retina

Analysis of developmental mechanisms during neuroembryogenesis, evaluation of toxicological effects and testing of neuroprotheses rely to an increasing extent on in vivo-like in vitro models. We have developed a novel organotypic culture system of the chick retina. Tissue slices of embryonic retinae were immobilized on glass coverslips by a fibrin clot and permanently rotated between the gas and medium phase, resulting in regular formation and the maintenance of the retinal cytoarchitecture. Selection of embryonic stage, slice thickness and specimen processing were optimized for culturing. Scanning electron microscopy revealed degradation during increasing culture periods of the fibrin clot, which was used for initial immobilization of explants on glass coverslips. Simultaneously, retinal cells became exposed on the tissue surface. Even after several weeks in vitro, formation and maintenance of plexiform and nuclear layers was evident as revealed by two specific monoclonal antibodies. Immunocytochemistry employing two additional photoreceptor- and radial Müller-antibodies indicated differentiation of neuronal and glial cells specific for the retina. The organotypic culture system promises to facilitate developmental studies of retinal development. Quantitative evaluation of Na(+)-channel blocker mexiletine impact on the histogenesis of retinal explants proved the organotypic culture system to be a valuable tool also for neurotoxicological investigations.