Isolation, characterization and establishment of an equine retinal glial cell line: a prerequisite to investigate the physiological function of Müller cells in the retina.

Abstract

Retinal Müller glial cells are of vital importance for maintaining a physiological environment within the retina. To this end, they provide highly specialized physiological properties to support neurons in structure, nutrition and metabolism. The purpose of this study was to isolate Müller cells from the equine retina, determine their characteristics and subsequently establish a stable equine Müller cell line (eqMC) that will provide a prerequisite for investigations on their physiological properties. Dissociated retinal cells were obtained from equine retinas by a papain digestion technique followed by trituration and a cell attachment method by which pure Müller cell cultures were achieved. Morphological examination was performed using phase-contrast microscopy, and further characterization of different subcultures was accomplished by immunocytochemistry. Cells of passage 1 showed distinct signals for glutamine synthetase and vimentin, whereas glial fibrillary acidic protein expression was almost absent. Characteristic expression patterns remained unaltered in all subcultures. Furthermore, cultured Müller cells stably expressed the microfilament alpha-smooth muscle actin, the proliferation marker Ki67 and the membrane channels Kir4.1 and aquaporin 4. The present study introduces the eqMC-7 that will facilitate studies investigating the physiological role of Müller cells within the equine retina.