Human melanopsin-AAV2/8 transfection to retina transiently restores visual function in rd1 mice.
OBJECTIVE
To explore whether ectopic expression of human melanopsin can effectively and safely restore visual function in rd1 mice.


METHODS
Hematoxylin-eosin staining of retinal sections from rd1 mice was used to detect the thickness of the outer nuclear layer to determine the timing of surgery. We constructed a human melanopsin-AAV2/8 viral vector and injected it into the subretinal space of rd1 mice. The Phoenix Micron IV system was used to exclude the aborted injections, and immunohistochemistry was used to validate the ectopic expression of human melanopsin. Furthermore, visual electrophysiology and behavioral tests were used to detect visual function 30 and 45d after the injection. The structure of the retina was compared between the human melanopsin-injected group and phosphate buffer saline (PBS)-injected group.


RESULTS
Retinas of rd1 mice lost almost all of their photoreceptors on postnatal day 28 (P28). We therefore injected the human melanopsin-adeno-associated virus (AAV) 2/8 viral vector into P30 rd1 mice. After excluding aborted injections, we used immunohistochemistry of the whole mount retina to confirm the ectopic expression of human melanopsin by co-expression of human melanopsin and YFP that was carried by a viral vector. At 30d post-injection, visual electrophysiology and the behavioral test significantly improved. However, restoration of vision disappeared 45d after human melanopsin injection. Notably, human melanopsin-injected mice did not show any structural differences in their retinas compared with PBS-injected mice.


CONCLUSIONS
Ectopic expression of human melanopsin effectively and safely restores visual function in rd1 mice.
Southwest Hospital, Southwest Eye Hospital, Third Military Medical University, Chongqing 400038, China; Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing 400038, China.
Ming-Ming
MM
Liu
Southwest Hospital, Southwest Eye Hospital, Third Military Medical University, Chongqing 400038, China; Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing 400038, China.
Jia-Man
JM
Dai
Southwest Hospital, Southwest Eye Hospital, Third Military Medical University, Chongqing 400038, China; Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing 400038, China.
Wen-Yi
WY
Liu
Southwest Hospital, Southwest Eye Hospital, Third Military Medical University, Chongqing 400038, China; Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing 400038, China.
Cong-Jian
CJ
Zhao
Departments of Anatomy and Ophthalmology, Li Ka Shing Faculty of Medicine, the University of Hong Kong, Hong Kong 200131, China.
Bin
B
Lin
Southwest Hospital, Southwest Eye Hospital, Third Military Medical University, Chongqing 400038, China; Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing 400038, China.
Zheng-Qin
ZQ
Yin
human melanopsin; retinal degenerative diseases; visual restoration