Organization of the basement membranes in the choroid plexus villi of the human brain

Abstract

BACKGROUND: The choroid plexus of the brain is the source of cerebrospinal fluid and a major component of the blood–cerebrospinal fluid barrier, providing active transport of only essential substances and preventing the entry of harmful substances, including proinflammatory molecules, pathogens, and toxins. Basement membranes of the choroid plexus play a special role in the implementation of barrier functions, which underlie the choroidal epithelium and capillary endothelium, and serve as an additional filter for substances penetrating from the blood into the cerebrospinal fluid. The morphological organization of basement membranes in the villi of the human choroid plexus has not been examined extensively. AIM: to analyze the organization of basement membranes in the villi of the human telencephalon choroid plexus by immunohistochemical detection of type IV collagen. MATERIALS AND METHODS: The study was performed on archival materials from the choroid plexus of the human brain (n=10; age 29–50 years) using immunohistochemical methods for detecting type IV collagen. RESULTS: An immunohistochemical reaction using antibodies to type IV collagen showed the distribution of this protein in the subepithelial area and stroma of the choroid plexus villi. All immunopositive structures had clear contours. No reaction in the cell cytoplasm or a nonspecific background was noted. Contacts of subepithelial and subcapillary basement membranes labeled with antibodies to type IV collagen were not detected. CONCLUSION: The results showed different organization of the basement membranes of the villi of the choroid plexus of the human brain in the subepithelial and perivascular areas. In this case, the subepithelial and perivascular components containing type IV collagen did not merge.