title: Distribution of immunoglobulin superfamily members ICAM-1, -2, -3, and the beta 2 integrin LFA-1 in multiple sclerosis lesions.
abstract: To identify potential molecular substrates for leukocyte trafficking and activation in multiple sclerosis (MS) brain, we determined the immunocytochemical distribution of the beta, integrin lymphocyte-function-associated antigen-1 (LFA-1) and its major ligands, intercellular adhesion molecule (ICAM)-1, ICAM-2, and ICAM-3 in MS tissue. Colocalization of these adhesion molecules with lineage-specific markers was analyzed by dual-labeling immunocytochemistry and confocal microscopy. ICAM-1 and ICAM-2 were detected on endothelial cells, and ICAM-3 immunoreactivity was restricted to infiltrating leukocytes. In control brain, 10% of glucose transporter-1 positive vessels contained ICAM-1 immunoreactivity on their luminal surface and 21% were ICAM-2-positive. A significant increase in ICAM-1-positive vessels was found in MS brains. This increase was greater in MS lesions (81% of vessels) than in nonlesion areas (37% of vessels). A significant increase in ICAM-1-positive vessels was found in encephalitis (55% of vessels) but not in Parkinson's (17% of vessels) brains. The percentage of vessels expressing ICAM-2 was not increased in MS, encephalitis, or Parkinson's brains. Both ICAM-3 and LFA-1 were detected on the vast majority of infiltrating lymphocytes and monocytes in and near MS lesions, and these cells were often closely apposed to each other. In addition, LFA-1 was detected on activated microglia located close to the edge of demyelinating lesions. ICAM-3-positive leukocytes were often closely apposed to LFA-1-positive microglia. These results suggest a role for ICAM-1, -2, and LFA-1 in the transendothelial migration of leukocytes into MS brain and a role for ICAM 3/LFA-1 interactions in the activation of lymphocytes, monocytes, and microglia in MS lesions.
authors.affiliation: Department of Neurosciences, Cleveland Clinic Foundation, Ohio 44195, USA.
authors.forename: L
authors.initials: L
authors.lastname: Bö
authors.forename: J W
authors.initials: JW
authors.lastname: Peterson
authors.forename: S
authors.initials: S
authors.lastname: Mørk
authors.forename: P A
authors.initials: PA
authors.lastname: Hoffman
authors.forename: W M
authors.initials: WM
authors.lastname: Gallatin
authors.forename: R M
authors.initials: RM
authors.lastname: Ransohoff
authors.forename: B D
authors.initials: BD
authors.lastname: Trapp
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000032:analysis*; D000943:Antigens, Differentiation; D001921:Brain / Q000166:cytology / Q000276:immunology; D001923:Brain Chemistry; D015815:Cell Adhesion Molecules / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D004727:Endothelium / Q000737:chemistry / Q000166:cytology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis*; D007962:Leukocytes / Q000737:chemistry; D016169:Lymphocyte Function-Associated Antigen-1 / Q000032:analysis*; D018613:Microscopy, Confocal; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000276:immunology / Q000378:metabolism*
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D015815:Cell Adhesion Molecules; C065289:ICAM2 protein, human; C483616:ICAM3 protein, human; D016169:Lymphocyte Function-Associated Antigen-1; D018799:Intercellular Adhesion Molecule-1