Borel,
The endothelial cells in the brain being discussed are the lining of the blood vessels. The tight junctions between the epithelial cells of the blood vessels are part of the blood brain barrier (BBB) keeping unwanted cells and large molecules out of the brain. The brain is fussy about who and what it allows in. Blood vessels traverse the brain but are not really brain tissue (like the glass tunnels in the aquarium. We are near the sharks, not with them).
I expect that the majority of the endothelial inflammation is from viral infection, though cytokines from inflammation elsewhere can result in damage/leaky junctions in the blood vessels and disruption of the BBB.
RANTES can be produced outside or inside the brain in response to infection or injury. Macrophages and T cells can follow the gradient into the brain across a disrupted bbb, though antigen specific T cells, even with an intact BBB, can enter, if antigen presenting cells (microglia
and I believe astrocytes) with the antigen to which the T cells are attracted lie just on the other side of the BBB. Leronlimab will stop trafficking of the “non-specific” macrophage response due to RANTES, but not to
my knowledge antigen-driven T cell migration.
I believe this is mostly correct. MD Virologist, Ohm20
and others can correct my (hopefully minor) errors.
The endothelial cells in the brain being discussed are the lining of the blood vessels. The tight junctions between the epithelial cells of the blood vessels are part of the blood brain barrier (BBB) keeping unwanted cells and large molecules out of the brain. The brain is fussy about who and what it allows in. Blood vessels traverse the brain but are not really brain tissue (like the glass tunnels in the aquarium. We are near the sharks, not with them).
I expect that the majority of the endothelial inflammation is from viral infection, though cytokines from inflammation elsewhere can result in damage/leaky junctions in the blood vessels and disruption of the BBB.
RANTES can be produced outside or inside the brain in response to infection or injury. Macrophages and T cells can follow the gradient into the brain across a disrupted bbb, though antigen specific T cells, even with an intact BBB, can enter, if antigen presenting cells (microglia
and I believe astrocytes) with the antigen to which the T cells are attracted lie just on the other side of the BBB. Leronlimab will stop trafficking of the “non-specific” macrophage response due to RANTES, but not to
my knowledge antigen-driven T cell migration.
I believe this is mostly correct. MD Virologist, Ohm20
and others can correct my (hopefully minor) errors.
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