title: Infliximab counteracts tumor necrosis factor-α-enhanced induction of matrix metalloproteinases that degrade claudin and occludin in non-pigmented ciliary epithelium.
abstract: Infliximab, a monoclonal antibody directed against human tumor necrosis factor-alpha (TNF-α), effectively treats anterior uveitis, which can accompany Behçet's disease. Here, we investigated the underlying mechanism of this action. We examined human, non-pigmented ciliary epithelial cells (HNPCECs), which make up the blood-aqueous barrier (BAB) in the uvea. We measured the expression levels of matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs in the presence or absence of TNF-α using quantitative, real-time polymerase chain reaction and enzyme-linked immunosorbent assays. The expression of MMP-1, MMP-3, and MMP-9 increased in the presence of TNF-α, and the addition of infliximab reversed the increase. The TNF-α effects were more attenuated when infliximab was added before than when it was added after TNF-α exposure. Gelatin zymography demonstrated that the protease activity of these MMPs was also increased in the presence of TNF-α and attenuated with infliximab. Immunostaining showed that MMP-1, MMP-3, and MMP-9 degraded claudin-1 and occludin in HNPCECs and in non-pigmented ciliary epithelial cells of the swine ciliary body. In a monolayer of HNPCECs, we found that permeability was significantly increased with MMP treatment. Thus, TNF-α increased levels of MMPs in cells that form the BAB, and MMPs degraded components of the tight junctions in the BAB, which increased permeability through the cellular barrier. Furthermore, infliximab effectively attenuated the TNF-α-induced increases in MMP expression in cells that make up the BAB. These findings might suggest a basis for the clinical prevention of anterior uveitis.
authors.affiliation: Department of Ophthalmology, Aichi Medical University, Aichi, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamada
authors.forename: Masahiko
authors.initials: M
authors.lastname: Yoneda
authors.forename: Shingo
authors.initials: S
authors.lastname: Inaguma
authors.forename: Daisuke
authors.initials: D
authors.lastname: Watanabe
authors.forename: Shogo
authors.initials: S
authors.lastname: Banno
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yoshikawa
authors.forename: Keigo
authors.initials: K
authors.lastname: Mizutani
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Iwaki
authors.forename: Masahiro
authors.initials: M
authors.lastname: Zako
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology*; D002478:Cells, Cultured; D002924:Ciliary Body / Q000187:drug effects / Q000378:metabolism*; D062445:Claudin-1 / Q000037:antagonists & inhibitors* / Q000378:metabolism; D015536:Down-Regulation / Q000187:drug effects / Q000276:immunology; D004790:Enzyme Induction / Q000187:drug effects / Q000502:physiology; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D000069285:Infliximab; D061965:Matrix Metalloproteinase Inhibitors / Q000378:metabolism / Q000633:toxicity; D020782:Matrix Metalloproteinases / Q000096:biosynthesis / Q000378:metabolism*; D062793:Occludin / Q000037:antagonists & inhibitors* / Q000378:metabolism; D013552:Swine; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors* / Q000633:toxicity*
chemical_list: D000911:Antibodies, Monoclonal; C568108:CLDN1 protein, human; D062445:Claudin-1; D061965:Matrix Metalloproteinase Inhibitors; C568985:OCLN protein, human; D062793:Occludin; D014409:Tumor Necrosis Factor-alpha; D000069285:Infliximab; D020782:Matrix Metalloproteinases