Drusen-associated photoreceptor changes in the retina. (
A) MWS-cone opsin immunoreactivity (
red) demonstrates the physicial deflection of a cone outer segment (OS) that overlies three small drusen. ApoE immunoreactivity (
blue) labels drusen, as well as the choroid and portions of the retina. Faint lipofuscin autofluorescence within the RPE can also be detected (
red). (
B) Severe disruption of MWS-cone opsin immunoreactive OS (
green) is associated with large drusen (compare with
Fig. 2A ). Faint vimentin immunoreactivity (
red) can be detected in the retina, RPE, and choroid. Autofluorescent lipofuscin granules are also detectable within the RPE in this image. (
C) Severe disrpuption of cone OS (
green) length and density occurs overlying two drusen (ApoE,
blue). Adjacent Müller glial cells show increased vimentin immunoreactivity (
red). (
D) Intermediate filament expression in Müller cell processes (vimentin,
green) in the inner (INL) and outer nuclear layers (ONL) increases over drusen. MWS-opsin immunoreactivity labels the few remaining cone outer segments (
red) and ApoE (
blue) labels drusen. (
E) Müller glial cell microvilli (
arrows; CD44,
red) rarely exhibit detectable changes within the interphotoreceptor space, even in the presence of very large drusen. RPE autofluorescence is also
red in this image and drusen are labeled with anti-apoE (
blue). (
F) A large glial scar (GFAP,
green) has formed among rod opsin-immunoreactive inner segments (IS) and OS (
red) overlying drusen deposits (
asterisks,
blue). Opsin immunoreactivity is also present in rod cell bodies overlying this glial scar (
arrow). (
G) ApoE immunostaining (
blue) reveals the fuzzy borders and amorphous shape of soft drusen in the macula (
brackets). ApoE immunoreactivity is also present in Müller glial processes within the outer plexiform layer (OPL) of the retina. MWS-cone opsin immunolabeling (
green) over soft drusen is less frequent and more disorganized compared with adjacent regions not overlying soft drusen. (
H) A large glial scar (GFAP,
green) has formed over ApoE-immunoreactive soft drusen (
blue, brackets). Opsin antibodies (
red) intensely label rod cell bodies, axons, and axon terminal in this region of the retina.