title: Neutralizing anti-interleukin-1β antibodies modulate fetal blood-brain barrier function after ischemia.
abstract: We have previously shown that increases in blood-brain barrier permeability represent an important component of ischemia-reperfusion related brain injury in the fetus. Pro-inflammatory cytokines could contribute to these abnormalities in blood-brain barrier function. We have generated pharmacological quantities of mouse anti-ovine interleukin-1β monoclonal antibody and shown that this antibody has very high sensitivity and specificity for interleukin-1β protein. This antibody also neutralizes the effects of interleukin-1β protein in vitro. In the current study, we hypothesized that the neutralizing anti-interleukin-1β monoclonal antibody attenuates ischemia-reperfusion related fetal blood-brain barrier dysfunction. Instrumented ovine fetuses at 127 days of gestation were studied after 30 min of carotid occlusion and 24h of reperfusion. Groups were sham operated placebo-control- (n=5), ischemia-placebo- (n=6), ischemia-anti-IL-1β antibody- (n=7), and sham-control antibody- (n=2) treated animals. Systemic infusions of placebo (0.154M NaCl) or anti-interleukin-1β monoclonal antibody (5.1±0.6 mg/kg) were given intravenously to the same sham or ischemic group of fetuses at 15 min and 4h after ischemia. Concentrations of interleukin-1β protein and anti-interleukin-1β monoclonal antibody were measured by ELISA in fetal plasma, cerebrospinal fluid, and parietal cerebral cortex. Blood-brain barrier permeability was quantified using the blood-to-brain transfer constant (Ki) with α-aminoisobutyric acid in multiple brain regions. Interleukin-1β protein was also measured in parietal cerebral cortices and tight junction proteins in multiple brain regions by Western immunoblot. Cerebral cortical interleukin-1β protein increased (P<0.001) after ischemia-reperfusion. After anti-interleukin-1β monoclonal antibody infusions, plasma anti-interleukin-1β monoclonal antibody was elevated (P<0.001), brain anti-interleukin-1β monoclonal antibody levels were higher (P<0.03), and interleukin-1β protein concentrations (P<0.03) and protein expressions (P<0.001) were lower in the monoclonal antibody-treated group than in placebo-treated-ischemia-reperfusion group. Monoclonal antibody infusions attenuated ischemia-reperfusion-related increases in Ki across the brain regions (P<0.04), and Ki showed an inverse linear correlation (r= -0.65, P<0.02) with anti-interleukin-1β monoclonal antibody concentrations in the parietal cortex, but had little effect on tight junction protein expression. We conclude that systemic anti-interleukin-1β monoclonal antibody infusions after ischemia result in brain anti-interleukin-1β antibody uptake, and attenuate ischemia-reperfusion-related interleukin-1β protein up-regulation and increases in blood-brain barrier permeability across brain regions in the fetus. The pro-inflammatory cytokine, interleukin-1β, contributes to impaired blood-brain barrier function after ischemia in the fetus.
authors.affiliation: Department of Pediatrics, The Alpert Medical School of Brown University, Women & Infants Hospital of Rhode Island, Providence, RI, USA.
authors.forename: Xiaodi
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Pediatrics, The Alpert Medical School of Brown University, Women & Infants Hospital of Rhode Island, Providence, RI, USA.
authors.forename: Grazyna B
authors.initials: GB
authors.lastname: Sadowska
authors.affiliation: Department of Pediatrics, The Alpert Medical School of Brown University, Women & Infants Hospital of Rhode Island, Providence, RI, USA.
authors.forename: Jiyong
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Pediatrics, The Alpert Medical School of Brown University, Women & Infants Hospital of Rhode Island, Providence, RI, USA.
authors.forename: Jeong-Eun
authors.initials: JE
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, The Alpert Medical School of Brown University, Women & Infants Hospital of Rhode Island, Providence, RI, USA.
authors.forename: Erin E
authors.initials: EE
authors.lastname: Cummings
authors.affiliation: Department of Pediatrics, The Alpert Medical School of Brown University, Women & Infants Hospital of Rhode Island, Providence, RI, USA.
authors.forename: Courtney A
authors.initials: CA
authors.lastname: Bodge
authors.affiliation: ProThera Biologics, Inc., Providence, RI, USA.
authors.forename: Yow-Pin
authors.initials: YP
authors.lastname: Lim
authors.affiliation: Department of Electrical, Computer, and Biomedical Engineering, University of Rhode Island, Kingston, RI, USA.
authors.forename: Oleksandr
authors.initials: O
authors.lastname: Makeyev
authors.affiliation: Department of Electrical, Computer, and Biomedical Engineering, University of Rhode Island, Kingston, RI, USA.
authors.forename: Walter G
authors.initials: WG
authors.lastname: Besio
authors.affiliation: Department of Neurology, The Alpert Medical School of Brown University, Rhode Island Hospital, Providence, RI, USA.
authors.forename: John
authors.initials: J
authors.lastname: Gaitanis
authors.affiliation: Department of Pediatrics, The Alpert Medical School of Brown University, Women & Infants Hospital of Rhode Island, Providence, RI, USA.
authors.forename: Steven W
authors.initials: SW
authors.lastname: Threlkeld
authors.affiliation: Geriatric Research Educational, and Clinical Center, Veterans Affairs Puget Sound Health Care System, Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA, USA.
authors.forename: William A
authors.initials: WA
authors.lastname: Banks
authors.affiliation: Department of Pediatrics, The Alpert Medical School of Brown University, Women & Infants Hospital of Rhode Island, Providence, RI, USA. Electronic address: bstonestreet@wihri.org.
authors.forename: Barbara S
authors.initials: BS
authors.lastname: Stonestreet
mesh_terms: D000818:Animals; D057134:Antibodies, Neutralizing / Q000494:pharmacology / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D001812:Blood-Brain Barrier / Q000187:drug effects* / Q000503:physiopathology; D001921:Brain / Q000196:embryology / Q000378:metabolism; D002199:Capillary Permeability / Q000187:drug effects; D016893:Carotid Stenosis / Q000150:complications; D016207:Cytokines / Q000378:metabolism; D004195:Disease Models, Animal; D004622:Embryo, Mammalian; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005311:Fetal Hypoxia / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology*; D006340:Heart Rate, Fetal / Q000187:drug effects; D053583:Interleukin-1beta / Q000276:immunology* / Q000378:metabolism; D051379:Mice; D011247:Pregnancy; D012039:Regional Blood Flow / Q000187:drug effects; D012756:Sheep; D062725:Tight Junction Proteins / Q000378:metabolism
chemical_list: D057134:Antibodies, Neutralizing; D016207:Cytokines; D053583:Interleukin-1beta; D062725:Tight Junction Proteins
keywords: Blood–brain barrier; Brain; Cytokines; Interleukin-1β; Ischemia–reperfusion; Monoclonal antibody; Ovine fetus; Sheep