Mouse monoclonal antibody towards e1 specific epitope blocks viral entry and intracellular viral replication in vitro.
We characterized viral neutralization by a murine monoclonal antibody (mAb315) developed against conserved E1 specific epitope aa 315-323 at pre- and post-binding steps of infection into Huh7 cells. Detection of native virus in infected Huh7 cells by mAb315 were demonstrated by immunostaining. Inhibitions of viral entry by three different concentrations of mAb315 were measured by intracellular amplification of HCV RNA post infection. HCV RNA positive sera from 24 patients were used to infect Huh7 cell line in absence or presence of mouse monoclonal antibody produced in Balb/c mice or culture supernatant of mouse hybrid cells. Monoclonal Ab mAb315 could detect synthetic peptide p315 adsorbed on peripheral human lymphocytes by flow cytometry and showed high immuno reactivity to E1 viral antigen in infected Huh7 cells by immunostaining. Antibody-mediated neutralization assays demonstrated the ability of mAb315 to block HCV binding/entry to target cells at 0.73 mg/mL ascitic fluid or 250 µg/mL culture supernatant of mouse hybrid cells. Sixteen of 24 infected sera could infect Huh7 cells (67%). Binding/entry of HCV was completely blocked by mAb315 in 11/16 cases (69%). These findings suggest that mAb315 can induce HCV neutralization in vitro, which makes it a candidate for developing HCV therapeutic antibodies.
a Department of Microbial Biotechnology , National Research Center , Giza , Egypt.
Ashraf A
AA
Tabll
Rehab I
RI
Moustafa
Yasmine S
YS
El Abd
Noha G
NG
Bader El Din
Reem
R
El-Shenawy
Hassan
H
Yousef
Manal
M
Hussein
Reham M
RM
Dawood
Moataza H
MH
Omran
Mostafa K
MK
El-Awady
D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000276:immunology / Q000494:pharmacology*; D057134:Antibodies, Neutralizing / Q000096:biosynthesis / Q000276:immunology / Q000494:pharmacology*; D000915:Antibody Affinity; D000918:Antibody Specificity; D045744:Cell Line, Tumor; D017124:Conserved Sequence; D000939:Epitopes / Q000276:immunology; D016174:Hepacivirus / Q000187:drug effects* / Q000276:immunology; D022781:Hepatocytes / Q000187:drug effects / Q000276:immunology / Q000821:virology; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D010455:Peptides / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000276:immunology; D014759:Viral Envelope Proteins / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000276:immunology; D053586:Virus Internalization / Q000187:drug effects*; D014779:Virus Replication / Q000187:drug effects*
D000911:Antibodies, Monoclonal; D057134:Antibodies, Neutralizing; C087035:E1 protein, Hepatitis C virus; D000939:Epitopes; D010455:Peptides; D014759:Viral Envelope Proteins