Impairment of blood-cerebrospinal fluid barrier properties by retrovirus-activated T lymphocytes: reduction in cerebrospinal fluid-to-blood efflux of prostaglandin E2.

The choroid plexus epithelium forms the interface between the blood and the CSF. In conjunction with the tight junctions restricting the paracellular pathway, polarized specific transport systems in the choroidal epithelium allow a fine regulation of CSF-borne biologically active mediators. The highly vascularized stroma delimited by the choroidal epithelium can be a reservoir for retrovirus-infected or activated immune cells.

Pro-inflammatory cytokines modulate matrix metalloproteinase secretion and organic anion transport at the blood-cerebrospinal fluid barrier.

Neuroinflammation and neuroinfection trigger cytokine-mediated responses that include an increase in the cerebrospinal fluid (CSF) levels of pro-inflammatory matrix metalloproteinases (MMPs) and organic anions such as leukotrienes and prostaglandins. The choroid plexus (CP) epithelium forming the interface between the blood and the CSF regulates the CSF concentration of bioactive organic anions and is involved in neuro-immune regulation. We demonstrated that both fourth and lateral ventricle CPs are a source of pro- and active MMP-2 and MMP-9 in the brain.