title: IL-16 expression in lymphocytes and microglia in HIV-1 encephalitis.
abstract: IL-16 is a natural ligand for the CD4 molecule and is known for its chemotactic and anti-HIV-1 activities. We determined IL-16 expression in human brain tissue with HIV-1 encephalitis by specific immunocytochemistry and showed that infiltrating lymphocytes and activated microglia express IL-16. IL-16 immunoreactivity was particularly pronounced in microglial nodules. In vitro, human foetal microglia and not astrocytes produce IL-16, and HIV-1 infection up-regulates microglial IL-16 release in a Nef-dependent manner. These results support the notion that, in the brain, IL-16 is a macrophage-lineage specific modulator of the inflammatory response and HIV-1 expression. Recruitment of IL-16+ T cells and microglia/macrophages may represent an innate response to HIV-1 infection in the central nervous system that counterbalances viral stimulatory factors.
authors.affiliation: Department of Pathology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
authors.forename: M-L
authors.initials: ML
authors.lastname: Zhao
authors.forename: Q
authors.initials: Q
authors.lastname: Si
authors.forename: S C
authors.initials: SC
authors.lastname: Lee
mesh_terms: D015526:AIDS Dementia Complex / Q000235:genetics / Q000378:metabolism*; D001253:Astrocytes / Q000378:metabolism; D001921:Brain / Q000473:pathology; D002478:Cells, Cultured; D015497:HIV-1; D006801:Humans; D007150:Immunohistochemistry; D019410:Interleukin-16 / Q000096:biosynthesis* / Q000235:genetics; D008070:Lipopolysaccharides / Q000494:pharmacology; D008214:Lymphocytes / Q000378:metabolism*; D017628:Microglia / Q000378:metabolism*; D016612:Paraffin Embedding; D013268:Stimulation, Chemical; D013601:T-Lymphocytes / Q000378:metabolism; D016707:Tissue Fixation
chemical_list: D019410:Interleukin-16; D008070:Lipopolysaccharides