title: Dissection of human humoral immune response against hepatitis C virus E2 glycoprotein by repertoire cloning and generation of recombinant Fab fragments.
abstract: Demonstration of antibodies inhibiting key viral functions is the basis for the design of an effective vaccine. Dissection of the human antibody response by repertoire cloning may be a powerful means to address this issue. In this study, a panel of human monoclonal recombinant Fab fragments specific for hepatitis C virus (HCV) E2 envelope protein was generated. The selection procedure was designed to select for cross-genotype reactive antibodies. Sequences coding five different human recombinant Fabs specific for the HCV/E2 protein were cloned and characterized. The ability of the cloned antibody fragments to inhibit adhesion of recombinant envelope E2 protein to target cells was assayed. While affinity of the different antibody fragments appeared similar, activity in inhibiting E2 binding to target cells varied considerably from one Fab fragment to another. Two Fabs were not able to inhibit E2 binding at high concentration (40 microg/mL), while three other Fab clones were active in neutralizing 50% of the E2 binding at concentrations ranging from 3 to 0.35 microg/mL.
authors.affiliation: Institute of Microbiology, Facoltà di Medicina, Università Cattolica del Sacro Cuore, Roma, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Burioni
authors.forename: P
authors.initials: P
authors.lastname: Plaisant
authors.forename: A
authors.initials: A
authors.lastname: Manzin
authors.forename: D
authors.initials: D
authors.lastname: Rosa
authors.forename: V
authors.initials: V
authors.lastname: Delli Carri
authors.forename: F
authors.initials: F
authors.lastname: Bugli
authors.forename: L
authors.initials: L
authors.lastname: Solforosi
authors.forename: S
authors.initials: S
authors.lastname: Abrignani
authors.forename: P E
authors.initials: PE
authors.lastname: Varaldo
authors.forename: G
authors.initials: G
authors.lastname: Fadda
authors.forename: M
authors.initials: M
authors.lastname: Clementi
mesh_terms: D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology; D018604:Epitope Mapping; D005260:Female; D018937:Hepatitis C Antibodies / Q000276:immunology*; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000276:immunology*; D008875:Middle Aged; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000276:immunology; D014759:Viral Envelope Proteins / Q000276:immunology*; D014765:Viral Vaccines / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D018937:Hepatitis C Antibodies; D007140:Immunoglobulin Fab Fragments; D011994:Recombinant Proteins; D014759:Viral Envelope Proteins; D014765:Viral Vaccines; C091015:glycoprotein E2, Hepatitis C virus