part of part of epithelium choroid plexus choroid plexus epithelium epithelial tissue of chorioid plexus of cerebral hemisphere MA:0000824 UMLS:C1516506 UBERON:0003911 NCIT:C42079 The epithelial component of the choroid plexus. Consists of cuboidal epithelial cells surrounding a core of capillaries and loose connective tissue. epithelium of choroid plexus choroid plexus epithelial tissue BTO:0006008 FMA:242811 epithelial tissue of choroid plexus The CP epithelial layer is continuous with the ependymal cell layer that lines the ventricles, but unlike the ependyma, the epithelial layer has tight gap junctions between the cells on the side facing the ventricle (apical surface). These gap junctions prevent the majority of substances from crossing the cell layer into the CSF; thus the CP acts as a blood-CSF barrier EMAPA:36608