RT Journal Article
SR Electronic
T1 Development and characterization of a human model of arteriovenous malformation (AVM)-on-a-chip
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2022.01.20.477166
DO 10.1101/2022.01.20.477166
A1 Soon, Kayla
A1 Li, Mengyuan
A1 Wu, Ruilin
A1 Turner, Williamson D.
A1 Wythe, Joshua D.
A1 Fish, Jason E.
A1 Nunes, Sara S
YR 2022
UL http://biorxiv.org/content/early/2022/01/28/2022.01.20.477166.abstract
AB Brain arteriovenous malformations (AVMs) are a disorder wherein abnormal, enlarged blood vessels connect arteries directly to veins, without an intervening capillary bed. AVMs are one of the leading causes of hemorrhagic stroke in children and young adults. Most human sporadic brain AVMs are associated with genetic activating mutations in the KRAS gene. Our goal was to develop an in vitro model that would allow for simultaneous morphological and functional phenotypic data capture in real time during AVM disease progression. By generating human endothelial cells harboring a clinically relevant mutation found in most human patients (activating mutations within the small GTPase KRAS) and seeding them in a dynamic microfluidic cell culture system that enables vessel formation and perfusion, we demonstrate that vessels formed by KRAS4AG12V mutant endothelial cells (ECs) were significantly wider and more leaky than vascular beds formed by wild-type ECs, recapitulating key structural and functional hallmarks of human AVM pathogenesis. Immunofluorescence staining revealed a breakdown of adherens junctions in mutant KRAS vessels only, leading to increased vascular permeability, a hallmark of hemorrhagic stroke. Finally, pharmacological blockade of MEK kinase activity, but not PI3K inhibition, improved endothelial barrier function (decreased permeability) without affecting vessel diameter. Collectively, our studies describe the creation of human KRAS-dependent AVM-like vessels in vitro in a self-assembling microvessel platform that is amenable to phenotypic observation and drug delivery.Competing Interest StatementThe authors have declared no competing interest.