Non-invasive delivery of small interfering ribonucleic acid for reduction of Huntingtin expression in the brain is achieved using focused ultrasound to disrupt the blood-brain barrier

AbstractAn emerging approach with potential in improving the treatment of neurodegenerative diseases and brain tumors is the use of focused ultrasound (FUS) to bypass the blood–brain barrier (BBB) in a non-invasive and localized manner. A large body of pre-clinical work has paved the way for the gradual clinical implementation of FUS-induced BBB opening. Even though the safety profile of FUS treatments in rodents has been extensively studied, the histological and behavioral effects of clinically relevant BBB opening in large animals are relatively understudied. Here, we examine the histological and behavioral safety profile following localized BBB opening in non-human primates (NHPs), using a neuronavigation-guided clinical system prototype. We show that FUS treatment triggers a short-lived immune response within the targeted region without exacerbating the touch accuracy or reaction time in visual-motor cognitive tasks. Our experiments were designed using a multiple-case-study approach, in order to maximize the acquired data and support translation of the FUS system into human studies. Four NHPs underwent a single session of FUS-mediated BBB opening in the prefrontal cortex. Two NHPs were treated bilaterally at different pressures, sacrificed on day 2 and 18 post-FUS, respectively, and their brains were histologically processed. In separate experiments, two NHPs that were earlier trained in a behavioral task were exposed to FUS unilaterally, and their performance was tracked for at least 3 weeks after BBB opening. An increased microglia density around blood vessels was detected on day 2, but was resolved by day 18. We also detected signs of enhanced immature neuron presence within areas that underwent BBB opening, compared to regions with an intact BBB, confirming previous rodent studies. Logistic regression analysis showed that the NHP cognitive performance did not deteriorate following BBB opening. These preliminary results demonstrate that neuronavigation-guided FUS with a single-element transducer is a non-invasive method capable of reversibly opening the BBB, without substantial histological or behavioral impact in an animal model closely resembling humans. Future work should confirm the observations of this multiple-case-study work across animals, species and tasks.

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BOT-01 BLOOD-BRAIN BARRIER OPENING USING 220-KHZ TRANSCRANIAL MRI-GUIDED FOCUSED ULTRASOUND AND MICROBUBBLES IN MOUSE AND RAT

Neuro-Oncology Advances ◽

10.1093/noajnl/vdz039.053 ◽

2019 ◽

Vol 1 (Supplement_2) ◽

pp. ii12-ii12

Author(s):

Michiharu Yoshida ◽

Kazuo Maruyama ◽

Yasutaka Kato ◽

Rachmilevitch Itay ◽

Syuji Suzuki ◽

...

Keyword(s):

Brain Tumors ◽

Blood Brain Barrier ◽

Focused Ultrasound ◽

Brain Barrier ◽

Maximum Temperature ◽

Non Invasive ◽

Therapeutic Drugs ◽

Blood Brain ◽

Mri Guided ◽

Bbb Opening

Abstract OBJECTIVE In neuro-oncology, it is believed that one major obstacle to effective chemotherapy is the high vascularity and heterogenous permeability of brain tumors. Focused ultrasound (FUS) exposure with the microbubbles has been shown to transiently open the blood-brain barrier (BBB) without depositing thermal energy, and thus may enhance the delivery of various therapeutic drugs into brain tumors. The aim of this study was to evaluate the BBB opening using 220-kHz transcranial MRI-guided FUS (TcMRgFUS) device and microbubbles in mouse and rat. METHODS The experiments were performed with the 220-kHz ExAblate Neuro TcMRgFUS system (InSightec) and novel lipid bubbles (LB, Teikyo Univ.). Normal mouse and rat brains were irradiated with TcMRgFUS (output power, 5W; duration of irradiation, 30 s; duty cycle 100%) following intravenous injection of 6x107 LB per mouse and rat, respectively. On irradiation, target temperature rise & cavitation signal were monitored by MR thermometry and cavitation receiver, respectively. Immediately after irradiation, BBB opening and complications were detected based on T1, T2, T2*, and Gadolinium (Gd) enhanced T1-weighted images. RESULTS The maximum temperature of brain tissue was under 42 C. There were no risky-cavitation signals causing hemorrhage. The FUS-LB exposure induced successful BBB opening effect in both mouse and rat, confirmed by Gd enhancement in the target region, lateral ventricles, and sulcus. In addition, there were no complications such as edema, coagulation, and hemorrhage. CONCLUSIONS Although there remain many conditions to be optimized, BBB opening using a 220-kHz TcMRgFUS device and LB can offer a non-invasive and feasible drug delivery for brain malignancies.

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Moving toward Noninvasive, Focused Ultrasound Therapeutic Delivery of Drugs in the Brain: Prolonged Opening of Blood-Brain Barrier May Not Be Needed

Radiology ◽

10.1148/radiol.2019190410 ◽

2019 ◽

Vol 291 (2) ◽

pp. 467-468

Author(s):

Alexander L. Klibanov ◽

Nathan J. McDannold

Keyword(s):

Blood Brain Barrier ◽

Focused Ultrasound ◽

Brain Barrier ◽

Therapeutic Delivery ◽

Blood Brain ◽

The Brain

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Non-invasive delivery of stealth, brain-penetrating nanoparticles across the blood − brain barrier using MRI-guided focused ultrasound

Journal of Controlled Release ◽

10.1016/j.jconrel.2014.06.031 ◽

2014 ◽

Vol 189 ◽

pp. 123-132 ◽

Cited By ~ 132

Author(s):

Elizabeth Nance ◽

Kelsie Timbie ◽

G. Wilson Miller ◽

Ji Song ◽

Cameron Louttit ◽

...

Keyword(s):

Blood Brain Barrier ◽

Focused Ultrasound ◽

Brain Barrier ◽

Non Invasive ◽

Blood Brain ◽

Mri Guided

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Claudin-5 binder enhances focused ultrasound-mediated opening in an in vitro blood-brain barrier model

10.1101/2021.08.01.454692 ◽

2021 ◽

Author(s):

Ratneswary Sutharsan ◽

Liyu Chen ◽

Jonathan LF Lee ◽

Esteban Cruz ◽

Tishila Palliyaguru ◽

...

Keyword(s):

Cell Line ◽

Blood Brain Barrier ◽

Focused Ultrasound ◽

Brain Barrier ◽

Sodium Fluorescein ◽

General Strategy ◽

Blood Brain ◽

Barrier Opening ◽

The Brain ◽

Bbb Opening

Rationale: The blood-brain barrier (BBB) while functioning as a gatekeeper of the brain, impedes cerebral drug delivery. An emerging technology to overcome this limitation is focused ultrasound (FUS). When FUS interacts with intravenously injected microbubbles (FUS+MB), the BBB opens, transiently allowing the access of therapeutic agents into the brain. However, the ultrasound parameters need to be tightly tuned: when the acoustic pressure is too low there is no opening, and when it is too high, bleeds can occur. We therefore asked whether BBB permeability can be increased by combining FUS+MB with a second modality such that in a clinical setting lower acoustic pressures could be potentially used. Methods: Given that FUS achieves BBB opening by the disruption of tight junction (TJ) proteins such as claudin-5 of brain endothelial cells, we generated a stable MDCK II cell line (eGFP-hCldn5-MDCK II) that expresses fluorescently tagged human claudin-5. Two claudin-5 binders, mC5C2 (a peptide) and cCPEm (a truncated form of an enterotoxin), that have been reported previously to weaken the barrier, were synthesized and assessed for their abilities to enhance the permeability of cellular monolayers. We then performed a comparative analysis of single and combination treatments. Results: We successfully generated a novel cell line that formed functional monolayers as validated by an increased transendothelial electrical resistance (TEER) reading and a low (< 0.2%) permeability to sodium fluorescein (376 Da). We found that the binders exerted a time- and concentration-dependent effect on BBB opening when incubated over an extended period, whereas FUS+MB caused a rapid barrier opening followed by recovery after 12 hours within the tested pressure range. Importantly, preincubation with cCPEm prior to FUS+MB treatment resulted in greater barrier opening compared to either FUS+MB or cCPEm alone as measured by reduced TEER values and an increased permeability to fluorescently labelled 40 kDa dextran (FD40). Conclusion: The data suggest that pre-incubation with clinically suitable binders to TJ proteins may be a general strategy to facilitate safer and more effective ultrasound-mediated BBB opening in cellular and animal systems and potentially also for the treatment of human diseases of the brain.

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A Noninvasive Approach to Optogenetics Using Focused Ultrasound Blood Brain Barrier Disruption for the Delivery of Radioluminescent Particles

10.1101/2020.08.20.248302 ◽

2020 ◽

Author(s):

Megan Rich ◽

Eric Zhang ◽

Ashley Dickey ◽

Haley Jones ◽

Kelli Cannon ◽

...

Keyword(s):

Blood Brain Barrier ◽

Focused Ultrasound ◽

Brain Regions ◽

Brain Barrier ◽

Receptor Subtype ◽

Spatiotemporal Resolution ◽

Light Emitting ◽

Non Invasive ◽

Blood Brain ◽

Essential Components

AbstractOptogenetics, the genetic incorporation of light-sensitive proteins such as Channelrhodopsin-2 (ChR2) into target mammalian neurons, has enabled activation, silencing, and receptor subtype specific neuromodulation with high spatiotemporal resolution. However, the essential components of the ontogenetic system require invasive procedures with very few non-invasive alternatives preventing its use as a translational tool. The implantation of light emitting fibers deep within brain structures is both technically demanding and causes tissue scarring in target brain regions. To overcome these limitations, while maintaining the highly-tuned components of optogenetics we have developed a novel noninvasive alternative. Our approach replaces fibers with light-emitting radioluminescent particles (RLPs) that can be activated non-invasively with X-ray exposure. Here, we report successful noninvasive delivery of RLPs to target brain regions using MRI-guided focused ultrasound (FUS) blood brain barrier opening. In addition, FUS BBBO can be used to deliver viral vectors for light sensitive channel expression. Combined, these components can provide a completely non-invasive optogenetic system.

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Ultrasound-Mediated Blood-Brain Barrier Opening Improves Whole Brain Gene Delivery in Mice

Pharmaceutics ◽

10.3390/pharmaceutics13081245 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1245

Author(s):

Marie-Solenne Felix ◽

Emilie Borloz ◽

Khaled Metwally ◽

Ambre Dauba ◽

Benoit Larrat ◽

...

Keyword(s):

Gene Therapy ◽

Gene Delivery ◽

Blood Brain Barrier ◽

Focused Ultrasound ◽

Fold Increase ◽

Brain Barrier ◽

Whole Brain ◽

External Threats ◽

Blood Brain ◽

The Brain

Gene therapy represents a powerful therapeutic tool to treat diseased tissues and provide a durable and effective correction. The central nervous system (CNS) is the target of many gene therapy protocols, but its high complexity makes it one of the most difficult organs to reach, in part due to the blood-brain barrier that protects it from external threats. Focused ultrasound (FUS) coupled with microbubbles appears as a technological breakthrough to deliver therapeutic agents into the CNS. While most studies focus on a specific targeted area of the brain, the present work proposes to permeabilize the entire brain for gene therapy in several pathologies. Our results show that, after i.v. administration and FUS sonication in a raster scan manner, a self-complementary AAV9-CMV-GFP vector strongly and safely infected the whole brain of mice. An increase in vector DNA (19.8 times), GFP mRNA (16.4 times), and GFP protein levels (17.4 times) was measured in whole brain extracts of FUS-treated GFP injected mice compared to non-FUS GFP injected mice. In addition to this increase in GFP levels, on average, a 7.3-fold increase of infected cells in the cortex, hippocampus, and striatum was observed. No side effects were detected in the brain of treated mice. The combining of FUS and AAV-based gene delivery represents a significant improvement in the treatment of neurological genetic diseases.

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