Gene therapy restores vision-dependent behavior as well as retinal structure and function in a mouse model of RPE65 Leber congenital amaurosis.
Retinal pigment epithelium-specific protein 65 kDa (RPE65) is a protein responsible for isomerization of all-trans-retinaldehyde to its photoactive 11-cis-retinaldehyde and is essential for the visual cycle. RPE65 mutations can cause severe, early onset retinal diseases such as Leber congenital amaurosis (LCA). A naturally occurring rodent model of LCA with a recessive nonsense Rpe65 mutation, the rd12 mouse, displays a profoundly diminished rod electroretinogram (ERG), an absence of 11-cis-retinaldehyde and rhodopsin, an overaccumulation of retinyl esters in retinal pigmented epithelial (RPE) cells, and photoreceptor degeneration. rd12 mice were injected subretinally at postnatal day 14 with rAAV5-CBA-hRPE65 vector. RPE65 expression was found over large areas of RPE soon after treatment. This led to improved rhodopsin levels with ERG signals restored to near normal. Retinyl ester levels were maintained at near normal, and fundus and retinal morphology remained normal. All parameters of restored retinal health remained stable for at least 7 months. The Morris water maze behavioral test was modified to test rod function under very dim light; rd12 mice treated in one eye performed similar to normally sighted C57BL/6J mice, while untreated rd12 mice performed very poorly, demonstrating that gene therapy can restore normal vision-dependent behavior in a congenitally blind animal.
Pang
Ji-jing
JJ
Department of Ophthalmology, University of Florida, Gainesville, FL 32610, USA. jpang@eye.ufl.edu
Chang
Bo
B
Kumar
Ashok
A
Nusinowitz
Steven
S
Noorwez
Syed M
SM
Li
Jie
J
Rani
Asha
A
Foster
Thomas C
TC
Chiodo
Vince A
VA
Doyle
Thomas
T
Li
Huashi
H
Malhotra
Ritu
R
Teusner
Jacqueline T
JT
McDowell
J Hugh
JH
Min
Seok-Hong
SH
Li
Qiuhong
Q
Kaushal
Shalesh
S
Hauswirth
William W
WW
D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D002352:Carrier Proteins / Q000235:genetics*; D000229:Dependovirus; D004195:Disease Models, Animal; D004952:Esters; D005136:Eye Proteins / Q000235:genetics*; D015316:Genetic Therapy; D005822:Genetic Vectors; D051379:Mice; D008810:Mice, Inbred C57BL; D029242:Optic Atrophy, Hereditary, Leber / Q000235:genetics* / Q000473:pathology / Q000628:therapy*; D012160:Retina / Q000033:anatomy & histology* / Q000473:pathology / Q000502:physiology*; D012243:Rhodopsin / Q000096:biosynthesis; D014785:Vision, Ocular / Q000235:genetics*; D019745:cis-trans-Isomerases; D000099178:Retinoid Isomerohydrolase
D002352:Carrier Proteins; D004952:Esters; D005136:Eye Proteins; D012243:Rhodopsin; D019745:cis-trans-Isomerases; D000099178:Retinoid Isomerohydrolase