Lentiviral vector delivery of short hairpin RNA to NG2 and neurotrophin-3 promotes locomotor recovery in injured rat spinal cord.
OBJECTIVE
In this study we investigated the effect of neurotrophin-3 (NT-3) and knockdown of NG2, one of the main inhibitory chondroitin sulfate proteoglycans (CSPG), in the glial scar following spinal cord injury (SCI).


METHODS
Short hairpin (sh) RNA were designed to target NG2 and were cloned into a lentiviral vector (LV). A LV was also constructed containing NT-3. LV expressing NT-3, shRNA to NG2 or combinations of both vectors were injected directly into contused rat spinal cords 1 week post-injury. Six weeks post-injection of LV, spinal cords were examined by histology for changes in scar size and by immunohistochemistry for changes in expression of CSPG, NT-3, astrocytes, neurons and microglia/macrophages. Motor function was assessed using the Basso, Beattie and Bresnahan (BBB) locomotor scale.


RESULTS
Animals that received the combination treatment of LV shNG2 and LV NT-3 showed reduced scar size. These animals also showed an increase in levels of neurons and NG2, a decrease in levels of astrocytes and a significant functional recovery as assessed using the BBB locomotor scale at 2 weeks post-treatment.


CONCLUSIONS
The improvement in locomotor recovery and decrease in scar size shows the potential of this gene therapy approach as a therapeutic treatment for SCI.
Regenerative Medicine Institute , NUI Galway, Galway, Ireland.
Eleanor M
EM
Donnelly
Nicolas N
NN
Madigan
Gemma E
GE
Rooney
Andrew
A
Knight
Bingkun
B
Chen
Bret
B
Ball
Lisa
L
Kinnavane
Yolanda
Y
Garcia
Peter
P
Dockery
John
J
Fraher
Padraig M
PM
Strappe
Anthony J
AJ
Windebank
Timothy
T
O'Brien
Siobhan S
SS
McMahon
D000818:Animals; D000941:Antigens / Q000235:genetics / Q000627:therapeutic use*; D039481:CD11b Antigen / Q000378:metabolism; D060833:Cellular Microenvironment; D011508:Chondroitin Sulfate Proteoglycans / Q000378:metabolism; D002921:Cicatrix / Q000473:pathology / Q000503:physiopathology; D005260:Female; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000235:genetics; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007150:Immunohistochemistry; D016086:Lentivirus / Q000235:genetics*; D008124:Locomotion; D058580:Neurocan; D020933:Neurotrophin 3 / Q000235:genetics / Q000627:therapeutic use*; D011509:Proteoglycans / Q000235:genetics / Q000627:therapeutic use*; D034741:RNA, Small Interfering / Q000008:administration & dosage*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020127:Recovery of Function; D013119:Spinal Cord Injuries / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D013194:Staining and Labeling; D014404:Tubulin / Q000378:metabolism; D000099216:Chondroitin Sulfate Proteoglycan 4
D000941:Antigens; D039481:CD11b Antigen; D011508:Chondroitin Sulfate Proteoglycans; D005904:Glial Fibrillary Acidic Protein; D058580:Neurocan; D020933:Neurotrophin 3; D011509:Proteoglycans; D034741:RNA, Small Interfering; D014404:Tubulin; D000099216:Chondroitin Sulfate Proteoglycan 4; C539091:Ncan protein, rat; C488416:Tubb3 protein, rat