Fig. 1

Schematic of the mechanical stress device. RPE cells were grown on porous membranes of Transwell inserts (a). After 4 weeks, Transwells were placed upside down on a custom-made stage under a pen tip and controlled with a rotor (b). The pen tip was pushed against the Transwell membrane to permanently stretch focal regions of the membrane (c). The Transwell insert was rotated between impacts to produce 60 non-overlapping bumps in 2 min (approximately 2 s per impact) (d, e). The black boxes correspond to the perforated areas of the Transwell inserts and the inserts’ rotation is indicated following step d”