Mycobacteria employ two different mechanisms to cross the blood-brain barrier
Abstract
Central nervous system (CNS) infection by Mycobacterium tuberculosis is one of the most devastating complications of tuberculosis, in particular in early childhood. In order to induce CNS infection, M. tuberculosis needs to cross specialised barriers protecting the brain. How M. tuberculosis crosses the blood-brain barrier (BBB) and enters the CNS is not well understood. Here, we use transparent zebrafish larvae and the closely related pathogen Mycobacterium marinum to answer this question. We show that in the early stages of development, mycobacteria rapidly infect brain tissue, either as free mycobacteria or within circulating macrophages. After the formation of a functionally intact BBB, the infiltration of brain tissue by infected macrophages is delayed, but not blocked, suggesting that crossing the BBB via phagocytic cells is one of the mechanisms used by mycobacteria to invade the CNS. Interestingly, depletion of phagocytic cells did not prevent M. marinum from infecting the brain tissue, indicating that free mycobacteria can independently cause brain infection. Detailed analysis showed that mycobacteria are able to cause vasculitis by extracellular outgrowth in the smaller blood vessels and by infecting endothelial cells...Continue Reading
References
Citations
Clofazimine functionalized polymeric nanoparticles for brain delivery in the tuberculosis treatment.
Methods Mentioned
Software Mentioned
Related Concepts
Related Feeds
Blood Brain Barrier
The blood brain barrier is a border that separates blood from cerebrospinal fluid. Discover the latest search on this highly selective semipermeable membrane here.
Blood Brain Barrier Regulation in Health & Disease
The blood brain barrier is essential in regulating the movement of molecules and substances in and out of the brain. Disruption to the blood brain barrier and changes in permeability allow pathogens and inflammatory molecules to cross the barrier and may play a part in the pathogenesis of neurodegenerative disorders. Here is the latest research in this field.
Blood Brain Barrier Chips
The blood brain barrier (BBB) is comprised of endothelial cells that regulate the influx and outflux of plasma concentrations. Lab-on-a-chip devices allow scientists to model diseases and mechanisms such as the passage of therapeutic antibodies across the BBB. Discover the latest research on BBB chips here.