Soluble FLT1 Gene Therapy Alleviates Brain Arteriovenous Malformation Severity

Authors

Wan Zhu, University of California, San Francisco
Fanxia Shen, University of California, San Francisco
Lei Mao, University of California, San Francisco
Lei Zhan, University of California, San Francisco
Shuai Kang, University of California, San Francisco
Zhengda Sun, University of California, San Francisco
Jeffrey Nelson, University of California, San Francisco
Rui Zhang, University of California, San Francisco
Dingquan Zou, University of California, San Francisco
Cameron M. McDougall, University of California, San Francisco
Michael T. Lawton, University of California, San FranciscoFollow
Thiennu H. Vu, University of California, San Francisco
Zhijian Wu, National Eye Institute (NEI)
Abraham Scaria, Sanofi S.A.
Peter Colosi, BioMarin Pharmaceutical Inc.
John Forsayeth, University of California, San Francisco
Hua Su, University of California, San Francisco

Document Type

Article

Abstract

Background and Purpose - Brain arteriovenous malformation (bAVM) is an important risk factor for intracranial hemorrhage. Current therapies are associated with high morbidities. Excessive vascular endothelial growth factor has been implicated in bAVM pathophysiology. Because soluble FLT1 binds to vascular endothelial growth factor with high affinity, we tested intravenous delivery of an adeno-associated viral vector serotype-9 expressing soluble FLT1 (AAV9-sFLT1) to alleviate the bAVM phenotype. Methods - Two mouse models were used. In model 1, bAVM was induced in R26CreER;Eng2f/2f mice through global Eng gene deletion and brain focal angiogenic stimulation; AAV2-sFLT02 (an AAV expressing a shorter form of sFLT1) was injected into the brain at the time of model induction, and AAV9-sFLT1, intravenously injected 8 weeks after. In model 2, SM22αCre;Eng2f/2f mice had a 90% occurrence of spontaneous bAVM at 5 weeks of age and 50% mortality at 6 weeks; AAV9-sFLT1 was intravenously delivered into 4- to 5-week-old mice. Tissue samples were collected 4 weeks after AAV9-sFLT1 delivery. Results - AAV2-sFLT02 inhibited bAVM formation, and AAV9-sFLT1 reduced abnormal vessels in model 1 (GFP versus sFLT1: 3.66±1.58/200 vessels versus 1.98±1.29, P<0.05). AAV9-sFLT1 reduced the occurrence of bAVM (GFP versus sFLT1: 100% versus 36%) and mortality (GFP versus sFLT1: 57% [12/22 mice] versus 24% [4/19 mice], P<0.05) in model 2. Kidney and liver function did not change significantly. Minor liver inflammation was found in 56% of AAV9-sFLT1-treated model 1 mice. Conclusions - By applying a regulated mechanism to restrict sFLT1 expression to bAVM, AAV9-sFLT1 can potentially be developed into a safer therapy to reduce the bAVM severity.

Publication Date

5-1-2017

Publication Title

Stroke

ISSN

00392499

E-ISSN

15244628

Volume

48

Issue

5

First Page

1420

Last Page

1423

PubMed ID

28325846

Digital Object Identifier (DOI)

10.1161/STROKEAHA.116.015713

Recommended Citation

Zhu, Wan; Shen, Fanxia; Mao, Lei; Zhan, Lei; Kang, Shuai; Sun, Zhengda; Nelson, Jeffrey; Zhang, Rui; Zou, Dingquan; McDougall, Cameron M.; Lawton, Michael T.; Vu, Thiennu H.; Wu, Zhijian; Scaria, Abraham; Colosi, Peter; Forsayeth, John; and Su, Hua, "Soluble FLT1 Gene Therapy Alleviates Brain Arteriovenous Malformation Severity" (2017). Neurosurgery. 1181.
https://scholar.barrowneuro.org/neurosurgery/1181