title: Brain-penetrating tumor necrosis factor decoy receptor in the mouse.
abstract: Biologic tumor necrosis factor inhibitors (TNFIs) include TNF decoy receptors (TNFRs). TNFα plays a pathologic role in both acute and chronic brain disease. However, biologic TNFIs cannot be developed as brain therapeutics because these large molecule drugs do not cross the blood-brain barrier (BBB). To enable penetration of the brain via receptor-mediated transport, the human TNFR type II was re-engineered as an IgG fusion protein, where the IgG part is a chimeric monoclonal antibody (MAb) against the mouse transferrin receptor (TfR), and this fusion protein is designated cTfRMAb-TNFR. The cTfRMAb part of the fusion protein acts as a molecular Trojan horse to ferry the TNFR across the BBB via transport on the endogenous BBB TfR. cTfRMAb-TNFR was expressed by stably transfected Chinese hamster ovary cells and purified by affinity chromatography to homogeneity on electrophoretic gels. The fusion protein reacted with antibodies to both mouse IgG and the human TNFR and bound TNFα with high affinity (K(d) = 96 ± 34 pM). cTfRMAb-TNFR was rapidly transported into mouse brain in vivo after intravenous administration, and the brain uptake of the fusion protein was 2.8 ± 0.5% of injected dose per gram of brain, which is >45-fold higher than the brain uptake of an IgG that does not recognize the mouse TfR. This new IgG-TNFR fusion protein can be tested in mouse models of brain diseases in which TNFα plays a pathologic role.
authors.affiliation: Department of Medicine, University of California Los Angeles, Los Angeles, California, USA.
authors.forename: Qing-Hui
authors.initials: QH
authors.lastname: Zhou
authors.forename: Ruben J
authors.initials: RJ
authors.lastname: Boado
authors.forename: Eric Ka-Wai
authors.initials: EK
authors.lastname: Hui
authors.forename: Jeff Zhiqiang
authors.initials: JZ
authors.lastname: Lu
authors.forename: William M
authors.initials: WM
authors.lastname: Pardridge
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000378:metabolism; D001812:Blood-Brain Barrier / Q000378:metabolism*; D001921:Brain / Q000378:metabolism; D001927:Brain Diseases / Q000378:metabolism; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011990:Receptors, Transferrin / Q000276:immunology / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014162:Transfection; D053319:Tumor Necrosis Factor Decoy Receptors / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D011990:Receptors, Transferrin; D011993:Recombinant Fusion Proteins; D053319:Tumor Necrosis Factor Decoy Receptors; D014409:Tumor Necrosis Factor-alpha