title: Human transbodies to VP40 inhibit cellular egress of Ebola virus-like particles.
abstract: A direct acting anti-Ebola agent is needed. VP40, a conserved protein across Ebolavirus (EBOV) species has several pivotal roles in the virus life cycle. Inhibition of VP40 functions would lessen the virion integrity and interfere with the viral assembly, budding, and spread. In this study, cell penetrable human scFvs (HuscFvs) that bound to EBOV VP40 were produced by phage display technology. Gene sequences coding for VP40-bound-HuscFvs were subcloned from phagemids into protein expression plasmids downstream to a gene of cell penetrating peptide, i.e., nonaarginine (R9). By electron microscopy, transbodies from three clones effectively inhibited egress of the Ebola virus-like particles from human hepatic cells transduced with pseudo-typed-Lentivirus particles carrying EBOV VP40 and GP genes. Computerized simulation indicated that the effective HuscFvs bound to multiple basic residues in the cationic patch of VP40 C-terminal domain which are important in membrane-binding for viral matrix assembly and virus budding. The transbodies bound also to VP40 N-terminal domain and L domain peptide encompassed the PTAPPEY (WW binding) motif, suggesting that they might confer VP40 function inhibition through additional mechanism(s). The generated transbodies are worthwhile tested with authentic EBOV before developing to direct acting anti-Ebola agent for preclinical and clinical trials.
authors.affiliation: Center of Research Excellence on Therapeutic Proteins and Antibody Engineering, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
authors.forename: Salma
authors.initials: S
authors.lastname: Teimoori
authors.affiliation: Center of Research Excellence on Therapeutic Proteins and Antibody Engineering, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
authors.forename: Watee
authors.initials: W
authors.lastname: Seesuay
authors.affiliation: Center of Research Excellence on Therapeutic Proteins and Antibody Engineering, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
authors.forename: Surasak
authors.initials: S
authors.lastname: Jittavisutthikul
authors.affiliation: Department of Tropical Pathology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.
authors.forename: Urai
authors.initials: U
authors.lastname: Chaisri
authors.affiliation: Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
authors.forename: Nitat
authors.initials: N
authors.lastname: Sookrung
authors.affiliation: Center of Research Excellence on Therapeutic Proteins and Antibody Engineering, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand; Graduate Program in Immunology, Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
authors.forename: Jaslan
authors.initials: J
authors.lastname: Densumite
authors.affiliation: Center of Research Excellence on Therapeutic Proteins and Antibody Engineering, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
authors.forename: Nawannaporn
authors.initials: N
authors.lastname: Saelim
authors.affiliation: Center of Research Excellence on Therapeutic Proteins and Antibody Engineering, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
authors.forename: Monrat
authors.initials: M
authors.lastname: Chulanetra
authors.affiliation: Department of Tropical Molecular Biology and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.
authors.forename: Santi
authors.initials: S
authors.lastname: Maneewatch
authors.affiliation: Center of Research Excellence on Therapeutic Proteins and Antibody Engineering, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand. Electronic address: wanpen.cha@mahidol.ac.th.
authors.forename: Wanpen
authors.initials: W
authors.lastname: Chaicumpa
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000473:pathology / Q000648:ultrastructure / Q000821:virology; D045744:Cell Line, Tumor; D029043:Ebolavirus / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D054884:Host-Pathogen Interactions; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology / Q000648:ultrastructure / Q000821:virology; D008855:Microscopy, Electron, Scanning; D008958:Models, Molecular; D019151:Peptide Library; D011485:Protein Binding; D000072417:Protein Domains; D057127:Single-Chain Antibodies / Q000737:chemistry / Q000276:immunology / Q000494:pharmacology*; D014763:Viral Matrix Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D014771:Virion / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D057074:Virus Release / Q000187:drug effects* / Q000502:physiology
chemical_list: D019151:Peptide Library; D057127:Single-Chain Antibodies; C080981:VP40 protein, virus; D014763:Viral Matrix Proteins
keywords: Cell penetrating antibody (transbody); Ebola virus; Human scFv; Scanning electron microscopy; VP40; Virus-like particles