Functional and molecular characterization of ex vivo cultured neuronal- and glial- like cells from idiopathic epiretinal membranes

Purpose To test the proliferating potential and characterize the functional and molecular profile of cells growing out of human idopathic epiretinal membranes (iERMs) ex vivo. Methods iERMs were obtained from uneventful vitrectomies from cases with iERM. Preoperative and postoperative BCVA, CFT and TMV were compared. Ex vivo cultivation under adherent conditions was carried out and followed up to 6 days. Morphological and immunocytochemical characterization of the cells was carried out. The dynamics of the intracellular calcium was measured using fluorescent dye Fura-2 and imaged in response to pharmacological stimulation by acetylcholine (ACh) or mechanostimulation. Results Visual acuity improved in 9/10 patients. CFT and TMV dereased significantly 3 months after surgery. The cells from the iERMs formed sphere-like structures when cultured ex vivo. The diameter of the spheres increased by 5% at day 6 and kept an increasing tendency over a month. The cells growing out of the iERM spheres had mainly a glial- and some neuronal- like morphology. Stimulation of these cells with ACh or mechanostimulation induced intracellular calcium propagation in both cell phenotypes – in the neuronal-like cells resembling action potential from the soma to the dendrites. Immunocytochemistry confirmed presence of glial- and neuronal cell phenotype in the iERMs, as well as presence of pluripotency marker. Conclusion iERMs contain cells of neuronal- and glial- like origin which have proliferative and pluripotent potential, show functionality reflected through calcium dynamics upon ACh and mechano- stimulation, and a corresponding molecular phenotype.