Transcriptional and Structural Consequences of Acute Neurovascular Permeability on the Cerebral Endothelium via Low-Intensity Pulsed Ultrasound: Modeling Acute Blood Brain Barrier Disruption in Humans

Friday, May 3, 2024

1:55 PM – 1:59 PM CT

Location: S401ab

Presenting Author(s)

Andrew Gould

Medical Student
Department of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA

Co-Author(s)

CA

Christina Amidei, PhD

Research Associate Professor of Neurological Surgery
Department of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, United States
Victor A. Arrieta Gonzalez, MD PhD (he/him/his)

Post Doctoral Scientist
Department of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
Chicago, Illinois, United States
JB

John Bebawy, MD

Professor of Anesthesiology (Neuroanesthesia) and Neurological Surgery
Department of Anesthesiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, United States
GB

Guillaume Bouchoux, PhD

Investigator
Carthera, Lyon, France, United States
MC

Michael Canney, PhD

Investigator
Carthera, Lyon, France, United States
Brandyn Castro, MD

Resident
Department of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago,
Chicago, Illinois, United States
LC

Li Chen, MD PhD

Lab Manager
Department of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, United States
CD

Crismita Dmello, PhD

Post Doctoral Scientist
Department of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, United States
CG

Cristal Gomez, n/a

Clinical Research Coordinator
Department of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago,, United States
KH

Karl Habashy, MD

Research Fellow
Northwestern University
Beirut, Lebanon
YH

Ye Hou, PhD

Post-Doctoral Fellow
Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, United States
LI

Luisa Iruela Arispe, PhD

Chair, Department of Cell and Developmental Biology
Department of Cell and Developmental Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, United States
MK

Mikoto Kobayashi, n/a

Investigator
Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, United States
FK

Farida Korbova, PhD

Research Assistant Professor of Cell and Developmental Biology
Department of Cell and Developmental Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, United States
YL

Yu Luan, PhD

Post-Doctoral Fellow
Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, United States
HN

Hinda Najem, MD

Post Doctoral Scientist
Department of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, United States
AS

Adam Sonabend Wothalter, MD

Associate Professor of Neurological Surgery
Department of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
Chicago, Illinois, United States
Roger Stupp, MD

Chief of Neuro-oncology in the Department of Neurology
Northwestern Medicine Malnati Brain Tumor Institute of the Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University
Chicago, Illinois, United States
RW

Rachel Ward, n/a

Nurse Clinician
Department of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, United States
MY

Mark Youngblood, MD, PhD

Resident
Department of Neurosurgery, Northwestern University Feinberg School of Medicine, United States
FY

Feng Yue, PhD

Professor of Biochemistry and Molecular Genetics and Pathology
Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, United States
DZ

Daniel Zhang, B.A.

Medical Student
Rush University Medical Center, United States

Disclosure(s):

Andrew Gould: No financial relationships to disclose

Introduction: Transient permeability of the blood-brain barrier (BBB) has been observed following acute injury to the neurovasculature. Animal studies have shown that compromise of barrier integrity results in profound transcriptional and ultrastructural changes to the cerebral endothelium, indicating that these cells could play a role in reestablishing barrier function. This process is understudied in humans but could reveal valuable insights into mechanisms of neurovascular repair following injury. We therefore sought to characterize the transcriptional and structural consequences of BBB dysfunction in the human cerebral endothelium.

Methods: We used low-intensity pulsed ultrasound with microbubbles (LIPU/MB) to induce targeted and temporary BBB dysfunction in ineloquent peri-tumoral brain tissues of 6 patients undergoing stereotactic resection of recurrent glioblastoma. Intraoperative fluorescent microscopy was used to visualize opening of the BBB in real time. LIPU/MB-treated (“sonicated”) tissues were readily identifiable by their hyperfluorescence compared to non-sonicated tissues. Biopsies for sonicated and non-sonicated ineloquent peritumoral brain were acquired from each patient and analyzed using single-cell RNA sequencing and transmission electron microscopy (TEM).

Results: Transcriptional analysis showed that sonicated and non-sonicated endothelial cells clustered separately. Sonicated endothelial cells exhibited significantly different expression of genes previously linked to BBB function, such as MFSD2A (log2 Fold Change = 0.592, p=1.31E-36), Cav1 (log2 FC = -0.77, p=1.14E-32), VE-Cadherin (log2 FC= -0.2884647, adjusted p=3E-7), and COL4A1 (log2FC=-0.34, adjusted p=7.9E-10). These changes aligned with gene ontology themes such as Regulation of Endocytosis (Normalized expression score [NES] =-2.01), Cell-Cell Adhesion (NES = -2.04), Abnormality of the Cerebral Vasculature (NES = -2.01), and others. TEM analysis revealed a time-dependent decrease in the frequency of endothelial caveolae and an increase in the frequency of cytoplasmic vacuoles, granular deposits within the basement membrane, and rarefaction of the cytosol.

Conclusion : Our observations suggest that the gene expression and ultrastructural changes following LIPU/MB reflect the mechanical stress induced by the ultrasound. These alterations could signify efforts by the endothelium to restore its connection to the basement membrane. Future studies should investigate these pathways as mechanisms of neurovascular repair following injury.