title: HIV infection of human choroid plexus: a possible mechanism of viral entry into the CNS.
abstract: The present study examines the hypothesis that HIV infection of the choroid plexus (CPx) may be an important site of viral entry into the brain. Formalin-fixed, paraffin-embedded CPx was obtained from 25 patients with AIDS and 13 nonAIDS patients and was processed for light microscopy and for immunohistochemical detection of HIV gp41, T and B lymphocytes, monocytes/macrophages and endothelial cells. Eleven of the 13 nonAIDS CPx were normal and 2 contained inflammatory foci of undetermined etiology. The stroma contained T lymphocytes in all and monocytes in 22%; B lymphocytes and HIV antigen were absent. Choroid plexus of the AIDS cases contained opportunistic infections or lymphoma in 12 and inflammatory foci alone in 6; 7 were normal. T lymphocytes were present in 70% and monocytes in 50%. In addition to the stromal localization, monocytes also were present in supra-epithelial regions and within or adjacent to the capillary endothelium. HIV-positive cells in the CPx were found in 11 cases (44%) and in the supra-epithelial area in another 2. Their presence correlated with neither infection nor lymphoma of the CPx or brain. They were situated in the stroma, supra-epithelial region and (rarely) capillary endothelium. Immunohistochemistry on serial sections identified the HIV-infected cells as monocytes, including those by capillary endothelium and in supra-epithelial areas. The study demonstrates that the CPx contains HIV-infected monocytes in almost half of the cases. Their apposition to endothelium suggests hematogenous origin. These results support the hypothesis that HIV encephalitis may develop from CPx infection.
authors.affiliation: Department of Pathology, University of Miami School of Medicine, FL 33136, USA.
authors.forename: M F
authors.initials: MF
authors.lastname: Falangola
authors.forename: A
authors.initials: A
authors.lastname: Hanly
authors.forename: B
authors.initials: B
authors.lastname: Galvao-Castro
authors.forename: C K
authors.initials: CK
authors.lastname: Petito
mesh_terms: D017088:AIDS-Related Opportunistic Infections; D000163:Acquired Immunodeficiency Syndrome / Q000503:physiopathology / Q000821:virology*; D000328:Adult; D001812:Blood-Brain Barrier; D002490:Central Nervous System / Q000821:virology; D002831:Choroid Plexus / Q000821:virology*; D005260:Female; D015497:HIV-1 / Q000302:isolation & purification* / Q000502:physiology; D006801:Humans; D016483:Lymphoma, AIDS-Related; D008297:Male; D008875:Middle Aged