- Branch Retinal Vein Occlusion (BRVO)
- Cancer Vaccines
- CAR T-Cell Therapy
- Case Report Form (CRF)
- Celiac Disease
- Cell and Gene Therapies
- Cell Therapy
- Central Nervous System (CNS)
- Central Retinal Vein Occlusion (CRVO)
Blood-Brain Barrier (BBB)
What Is The Blood-Brain Barrier (BBB)? The blood-brain barrier (BBB) is a specialized network of cells and blood vessels that protect the brain from harmful substances in the blood while allowing essential nutrients to pass through.
The cells within the blood-brain barrier include:
- Endothelial cells
- Capillary basement membrane
What Does The Blood-Brain Barrier (BBB) Do?
- Maintains the homeostasis of the brain microenvironment
- Prevents the entry of toxic substances, pathogens, and immune cells into the brain
- Regulates the transport of nutrients and metabolic waste products
How Is The Blood-Brain Barrier Regulated?
The structure of the endothelial cells lining the capillaries is largely responsible for the degree of impermeability of the blood-brain barrier through:
- Stronger tight junctions seal the passage of substances between adjacent cells.
- Lack of fenestrations.
- Active transport mechanisms instead of passive uptake, such as pinocytic activity.
- Use of efflux transporters, such as P-glycoprotein, BRCP, and OATP, which actively remove compounds from the endothelial cells back into the peripheral circulation, thereby reducing CNS exposure.
- Metabolism of drugs and other endogenous substances by leveraging the actions of CYP 450 enzymes in the endothelium.
Source: Abbott NJ, Patabendige AAK, Dolman DEM, Yusof SR, Begley DJ. Structure and function of the blood-brain barrier. Neurobiol Dis. 2010;37(1):13-25. doi: 10.1016/j.nbd.2009.07.030.