Schematic drawing of the retina and depiction of the localization of the adeno-associated viral (AAV) particles found by electron microscopy. (a) Localization of AAV particles in the retina of P1, after subretinal injection of a rAAV2/4 vector. (b) Localization of AAV particles in the retina of D1 after subretinal injection of an AAV2/5 vector. (c) Localization of AAV particles in the retina of D2 after subretinal injection of an AAV2/2 vector. The red spotted circles indicate the location, where particles are found. The green circles indicate the cells in which transgene expression can be observed. IPL, inner plexiform layer; OPL, outer plexiform layer; RPE, retinal pigment epithelium.