Assessment of Blood-Brain Barrier Disruption in Stroke

Blood-brain barrier (BBB) damage is an important pathophysiological feature of ischemic stroke. It responds to stroke injury with increased permeability and reduced barrier function, along with degeneration of the basal lamina of the vessel wall. Due to increased BBB permeability, many secondary injury cascades are activated, including cytotoxic edema, disruption of cellular water and ion homeostasis, vasogenic edema, and fluid extravasation into the brain parenchyma. To better understand stroke pathogenesis and develop therapeutic interventions, ischemia-related BBB disruption needs to be studied using different preclinical stroke models.

Fig. 1. Disruption of the blood brain barrier 24 h following the photothrombotic stroke. (Weber et al., 2020)

Our BBB Disruption Assessment Service in Stroke

Ace Therapeutics provides a comprehensive service to evaluate BBB disruption during stroke for clients worldwide. Our experts can characterize BBB integrity in different stroke models.

Assessment of BBB Permeability in Vitro

We examine BBB function in the transendothelial electrical resistance (TEER) by measuring the electrical resistance of cell monolayers (e.g., brain endothelial cell lines, astrocytes). The TEER value reflects the integrity and permeability of the endothelial cells in a culture. This method is non-invasive and enables continuous monitoring of living cells at all stages from BBB disruption to post-stroke repair.

In addition, we offer BBB models composed of human primary brain endothelial cells, pericytes, and astrocytes for permeability assays and BBB pharmacokinetic studies.

Ex Vivo Assessment of BBB Disruption

After obtaining brain tissue from animal models of stroke, we offer a range of tools to quantify BBB disruption at various levels of injury severity.

• Evans Blue (EB) Dye

We can qualitatively assess BBB disruption by simple visualization of Evans blue-albumin complex within sectioned brain tissue. We offer colorimetric, spectrophotometric, or optical imaging to quantify the amount of EB extravasation in brain sections, regions of interest, or the entire brain. Data acquisition for this method is limited to a single time point, and results show complete extravasation of Evans blue-albumin complex from stroke onset to the time point of execution.

• Immunohistochemical or Immunofluorescent Staining

We can assess BBB destruction by immunohistochemical or immunofluorescent staining of blood proteins. We use microscopy to identify exuded albumin, fibrinogen, IgM, and IgG. This method allows cost-effective semi-quantitative assessment of BBB destruction and obtains spatial visualization information. Results are shown as total exudates since stroke induction.

• Quantitative Radiation Autoradiography

We can use a variety of radiolabeled compounds as tracers, such as the amino acid [14C] α-aminoisobutyric acid and 4-[18F] flunantipyrine, to perform quantitative radioautography to derive kinetic parameters of extravasation for BBB destruction. We can also prepare customized radiolabeled compounds to assess the transfer of specific compounds across the BBB.

In Vivo Assessment of BBB Disruption

We offer a variety of imaging techniques to monitor changes in blood-brain barrier permeability, assess effects on therapeutic drug uptake into the brain, and assess activity indicators such as transporter gene polymorphisms in animal models of stroke.

• Fluorescence Imaging
• Magnetic Resonance Imaging (MRI)
• Positron Emission Tomography (PET) Imaging
• Single-photon Emission Computed Tomography (SPECT) Imaging

Applications of BBB Disruption Assessment Service in Stroke

Our BBB disruption assessment service allows us to assist clients in:

• Studying the mechanisms of BBB disruption in stroke.
• Developing potential therapeutic targets to protect BBB integrity after stroke.

Ace Therapeutics combines different techniques to assess BBB permeability and dysfunction in preclinical animal stroke models to help you gain a comprehensive understanding of the pathological process of stroke. If you are interested in our services, please do not hesitate to contact us!

1. Weber, R. Z., et al. (2020). Characterization of the blood brain barrier disruption in the photothrombotic stroke model. Frontiers in physiology, 11, 586226.