title: Dengue Virus Nonstructural Protein 1-Induced Antibodies Cross-React with Human Plasminogen and Enhance Its Activation.
abstract: Dengue virus (DENV) infection is the most common mosquito-borne viral disease, and it can cause life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Abnormal activation of the coagulation and fibrinolysis system is one of the hallmarks of DHF/DSS. However, the mechanism underlying hemorrhage in DHF/DSS remains elusive. In previous studies, plasminogen (Plg) cross-reactive Abs, which can recognize DENV nonstructural protein (NS) 1, have been found in dengue patients. However, it is unclear whether these Abs are indeed induced by DENV NS1. Thus, we immunized mice with recombinant NS1 from both bacteria and drosophila to determine whether NS1 can induce Plg cross-reactive Abs. The results from the NS1-immunized mouse sera indicated that NS1 immunization induced Abs that could cross-react with Plg. To study the effects of these NS1-induced Plg cross-reactive Abs on fibrinolysis, we isolated several Plg cross-reactive anti-NS1 mAbs from these mice and found that some of them could enhance Plg activation. In addition, epitope mapping with a phage-displayed random peptide library revealed that one of these mAbs (2A5) could recognize NS1 C-terminal residues 305-311, which share sequence homology with Plg residues 590-597. A synthetic peptide of NS1 residues 305-311 could inhibit the binding of both 2A5 and its Fab to Plg and its enhanced activation. Thus, our results suggest that DENV NS1 can induce Plg cross-reactive Abs through molecular mimicry, which can enhance Plg activation and may contribute to the pathogenesis of DHF/DSS.
authors.affiliation: Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan 701; Center of Infectious Disease and Signaling Research, College of Medicine, National Cheng Kung University, Tainan, Taiwan 701; and.
authors.forename: Yung-Chun
authors.initials: YC
authors.lastname: Chuang
authors.affiliation: Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan 701;
authors.forename: Jessica
authors.initials: J
authors.lastname: Lin
authors.affiliation: Center of Infectious Disease and Signaling Research, College of Medicine, National Cheng Kung University, Tainan, Taiwan 701; and Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan 701.
authors.forename: Yee-Shin
authors.initials: YS
authors.lastname: Lin
authors.affiliation: Center of Infectious Disease and Signaling Research, College of Medicine, National Cheng Kung University, Tainan, Taiwan 701; and Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan 701.
authors.forename: Shuying
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan 701; Center of Infectious Disease and Signaling Research, College of Medicine, National Cheng Kung University, Tainan, Taiwan 701; and today@mail.ncku.edu.tw.
authors.forename: Trai-Ming
authors.identifier: http://orcid.org/0000-0003-3172-7432
authors.initials: TM
authors.lastname: Yeh
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology*; D000956:Antigens, Viral / Q000276:immunology; D015153:Blotting, Western; D003429:Cross Reactions / Q000276:immunology; D003716:Dengue Virus / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D018604:Epitope Mapping; D005342:Fibrinolysis / Q000276:immunology*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D018716:Molecular Mimicry; D010958:Plasminogen / Q000276:immunology*; D019595:Severe Dengue / Q000276:immunology; D017361:Viral Nonstructural Proteins / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D017361:Viral Nonstructural Proteins; D010958:Plasminogen