Table of Contents
What bacteria can cross the blood-brain barrier?
A limited number of blood-borne bacteria can cross the blood–CNS barriers and cause meningitis. The extracellular pathogens that are involved are usually Neisseria meningitidis, Streptococcus pneumoniae or, in newborns, group B Streptococcus and Escherichia coli K1.
How do microbes cross the blood-brain barrier?
Bacteria enter the central nervous system following a direct interaction with the luminal side of the cerebral endothelium, which constitutes the blood-brain barrier. To breach the barriers protecting the brain, extracellular pathogens must cross a monolayer of tight junction-expressing endothelial or epithelial cells.
What gets through the blood-brain barrier?
What is the blood-brain barrier and what does it do? Only water, certain gases (e.g. oxygen), and lipid-soluble substances can easily diffuse across the barrier (other necessary substances like glucose can be actively transported across the blood-brain barrier with some effort).
What is blood-brain barrier disruption?
Blood-brain barrier disruption therapy (BBBD) is an intensive, effective way of sending medication to brain tumors. The BBBD treatment allows medication to pass through the protective barrier. The largest possible amount of the drug is sent to the tumor and nearby tissue.
What structures create the blood-brain barrier?
The blood-brain barrier (BBB) is a diffusion barrier, which impedes influx of most compounds from blood to brain. Three cellular elements of the brain microvasculature compose the BBB-endothelial cells, astrocyte end-feet, and pericytes (PCs).
What structures make up the blood-brain barrier?
The blood-brain barrier is a multicellular, compound structure composed of endothelial cells, pericytes and astrocytes in direct contact with brain tissue. The BBB is a compound structure following the brain’s labyrinth of vasculature.
How do microorganisms cross the blood-brain barrier?
Three mechanisms for microorganism transfer across the blood-brain barrier: A) transcellular route, B) paracellular route and C) infected phagocyte route (Trojan Horse). Microbes that cross the BBB through the transcellular method cross into the CNS through endothelial cells.
What is the blood-brain barrier made of?
Diagram of a microvessel in the brain lined by the blood-brain barrier. The blood-brain barrier is a multicellular, compound structure composed of endothelial cells, pericytes and astrocytes in direct contact with brain tissue.
How does the brain protect itself from pathogens?
The brain is well protected against microbial invasion by cellular barriers, such as the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (BCSFB). In addition, cells within the central nervous system (CNS) are capable of producing an immune response against invading pathogens.
What is the blood bacterial barrier (BBB)?
Composed of many cell types, the BBB is both a structural and functional roadblock to microorganisms, such as bacteria, fungi, viruses or parasites, that may be circulating in the bloodstream.