title: Human brain microvascular endothelial cell traversal by Borrelia burgdorferi requires calcium signaling.
abstract: Neurological manifestations of Lyme disease (or neuroborreliosis) occur variably and while it is clear that Borrelia burgdorferi can invade the nervous system, how it does so is not well understood. Pathogen penetration through the blood brain barrier (BBB) is often influenced by calcium signaling in the endothelial cells triggered by extracellular host-pathogen interactions. We examined the traversal of B. burgdorferi across the human BBB using in vitro model systems constructed of human brain microvascular endothelial cells (HBMEC) grown on Costar Transwell inserts. Pretreatment of the cell monolayers with BAPTA-AM (an intracellular calcium chelator) or phospholipase C (PLC) inhibitor U73122 inhibited B. burgdorferi transmigration. By 5 h, BAPTA-AM significantly inhibited (82-99%; p <0.017) spirochete traversal of HBMEC compared to DMSO controls. Spirochete traversal was almost totally blocked (> or =99%; p <0.017) after pretreatment with the PLC-beta inhibitor U73122 as a result of barrier tightening based on electric cell-substrate impedance sensing (ECIS). The data suggest a role for calcium signaling in CNS spirochete invasion through endothelial cell barriers.
authors.affiliation: Department of Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA. dgrab1@jhmi.edu
authors.forename: D J
authors.initials: DJ
authors.lastname: Grab
authors.forename: E
authors.initials: E
authors.lastname: Nyarko
authors.forename: O V
authors.initials: OV
authors.lastname: Nikolskaia
authors.forename: Y V
authors.initials: YV
authors.lastname: Kim
authors.forename: J S
authors.initials: JS
authors.lastname: Dumler
mesh_terms: D025065:Borrelia burgdorferi / Q000472:pathogenicity*; D001921:Brain / Q000382:microbiology*; D020013:Calcium Signaling; D002460:Cell Line; D004533:Egtazic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D042783:Endothelial Cells / Q000382:microbiology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004963:Estrenes / Q000494:pharmacology; D006801:Humans; D011760:Pyrrolidinones / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D004963:Estrenes; D011760:Pyrrolidinones; C060229:1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione; C070379:1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester; D004533:Egtazic Acid