Fig. 1

Diagrammatic representation of key steps in the ‘pull-off’. A: After enucleation of the eye, an incision is made immediately posterior to the limbus (as indicated by the dashed line) and the anterior segment is removed by cutting circumferentially. B: Afterwards, the lens and vitreous are removed, exposing the retina. C, D: Four relieving cuts are made in the retina, which is then dissected out and laid flat on aPES filter, with the photoreceptor side facing down and making contact with the matte surface of the filter. E: The retina and filter are placed with the retina facing up on blotting paper, and a glass coverslip is gently placed on the nerve fiber layer of the retina. F: The filter-retina-coverslip stack is carefully inverted, and 7 µl of collagenase working solution are added to the back of the filter. After this is absorbed, another 7 µl of collagenase working solution are added. G: Once the collagenase has been completely absorbed, a 200 mg weight is lowered onto the inverted stack. The blotting paper is used to lift the entire assembly and place it in a 100 mm petri dish, which is then covered and placed on a heating block at 37 °C to incubate. H: After incubation, the weight is removed and the stack carefully placed on dry blotting paper with the coverslip facing up. After brief additional drying, the coverslip is gently removed, separating the inner limiting membrane and retinal astrocytes from the underlying retina