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A Human Monoclonal Antibody against Hepatitis B Surface Antigen with Potent Neutralizing Activity.

Cerino A, Bremer CM, Glebe D, Mondelli MU - PLoS ONE (2015)

Bottom Line: We describe the production and characterization of human monoclonal antibodies (mAb) specific for the major hepatitis B virus (HBV) S protein.The former recognized a denaturation-insensitive epitope within the p24 protein whereas the latter recognized a denaturation-sensitive, conformational epitope located within the HBsAg common "a" determinant.Recombinant variable heavy and light domain sequences derived from mAb ADRI-2F3 were cloned into eukaryotic expression vectors and showed identical fine specificity and 1 log10 higher titer than the original IgG1λ.

View Article: PubMed Central - PubMed

Affiliation: Research Laboratories, Department of Infectious Diseases, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.

ABSTRACT
We describe the production and characterization of human monoclonal antibodies (mAb) specific for the major hepatitis B virus (HBV) S protein. The mAbs, two IgG1κ and one IgG1λ, were secreted by B-cell clones obtained from peripheral blood mononuclear cells (PBMC) of one person convalescent from acute hepatitis B and one vaccinated individual. The former recognized a denaturation-insensitive epitope within the p24 protein whereas the latter recognized a denaturation-sensitive, conformational epitope located within the HBsAg common "a" determinant. This mAb, denominated ADRI-2F3, displayed a very high protective titer of over 43,000 IU/mg mAb and showed an extremely potent neutralizing activity in the in vitro model of HBV infection using primary hepatocytes from Tupaia belangeri as target. Recombinant variable heavy and light domain sequences derived from mAb ADRI-2F3 were cloned into eukaryotic expression vectors and showed identical fine specificity and 1 log10 higher titer than the original IgG1λ. It is envisaged that such mAb will be able to efficiently prevent HBV reinfection after liver transplantation for end-stage chronic HBV infection or infection after needle-stick exposure, providing an unlimited source of valuable protective anti-HBs antibody.

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Related in: MedlinePlus

Neutralizing activity of three human monoclonal antibodies PK-3D1, PK-10C7 and ADRI-2F3 in comparison with mouse monoclonal antibody MA18/7.It is shown herein that a dilution of 1:10,000 of monoclonal antibody supernatant ADRI-2F3 completely neutralizes the activity of HBV, whereas EC50 is reached at a dilution of 1: 100,000.
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pone.0125704.g002: Neutralizing activity of three human monoclonal antibodies PK-3D1, PK-10C7 and ADRI-2F3 in comparison with mouse monoclonal antibody MA18/7.It is shown herein that a dilution of 1:10,000 of monoclonal antibody supernatant ADRI-2F3 completely neutralizes the activity of HBV, whereas EC50 is reached at a dilution of 1: 100,000.

Mentions: This was analyzed for both ADRI- and PK-derived humAb using the neutralization assay described above. ADRI-2F3 supernatant showed strong neutralization activity up to 1:10,000 dilution. Since the specific IgG1λ concentration in the supernatant was 27 μg/ml it can be extrapolated that ADRI-2F3 efficiently neutralized HBV at concentrations of at least 2.7 ng/ml (Fig 2). Since the viral inoculum used for infection of PTH was 108/ml it can be derived that no more than 2.7 ng/ml were sufficient to neutralize 108 HBV particles. PK humAb supernatant showed contrasting behaviors. Thus, PK10C7 did not neutralize infection of PTH while PK3D1 showed moderate neutralizing activity down to a dilution of 1:102 (about 200 ng/ml) which proved to be at least as good as the standard murine MA18/7 anti-pre-S1 mAb used as positive neutralization standard (1:100, corresponding to a concentration of 10 μg/ml) (Fig 2).


A Human Monoclonal Antibody against Hepatitis B Surface Antigen with Potent Neutralizing Activity.

Cerino A, Bremer CM, Glebe D, Mondelli MU - PLoS ONE (2015)

Neutralizing activity of three human monoclonal antibodies PK-3D1, PK-10C7 and ADRI-2F3 in comparison with mouse monoclonal antibody MA18/7.It is shown herein that a dilution of 1:10,000 of monoclonal antibody supernatant ADRI-2F3 completely neutralizes the activity of HBV, whereas EC50 is reached at a dilution of 1: 100,000.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4414269&req=5

pone.0125704.g002: Neutralizing activity of three human monoclonal antibodies PK-3D1, PK-10C7 and ADRI-2F3 in comparison with mouse monoclonal antibody MA18/7.It is shown herein that a dilution of 1:10,000 of monoclonal antibody supernatant ADRI-2F3 completely neutralizes the activity of HBV, whereas EC50 is reached at a dilution of 1: 100,000.
Mentions: This was analyzed for both ADRI- and PK-derived humAb using the neutralization assay described above. ADRI-2F3 supernatant showed strong neutralization activity up to 1:10,000 dilution. Since the specific IgG1λ concentration in the supernatant was 27 μg/ml it can be extrapolated that ADRI-2F3 efficiently neutralized HBV at concentrations of at least 2.7 ng/ml (Fig 2). Since the viral inoculum used for infection of PTH was 108/ml it can be derived that no more than 2.7 ng/ml were sufficient to neutralize 108 HBV particles. PK humAb supernatant showed contrasting behaviors. Thus, PK10C7 did not neutralize infection of PTH while PK3D1 showed moderate neutralizing activity down to a dilution of 1:102 (about 200 ng/ml) which proved to be at least as good as the standard murine MA18/7 anti-pre-S1 mAb used as positive neutralization standard (1:100, corresponding to a concentration of 10 μg/ml) (Fig 2).

Bottom Line: We describe the production and characterization of human monoclonal antibodies (mAb) specific for the major hepatitis B virus (HBV) S protein.The former recognized a denaturation-insensitive epitope within the p24 protein whereas the latter recognized a denaturation-sensitive, conformational epitope located within the HBsAg common "a" determinant.Recombinant variable heavy and light domain sequences derived from mAb ADRI-2F3 were cloned into eukaryotic expression vectors and showed identical fine specificity and 1 log10 higher titer than the original IgG1λ.

View Article: PubMed Central - PubMed

Affiliation: Research Laboratories, Department of Infectious Diseases, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.

ABSTRACT
We describe the production and characterization of human monoclonal antibodies (mAb) specific for the major hepatitis B virus (HBV) S protein. The mAbs, two IgG1κ and one IgG1λ, were secreted by B-cell clones obtained from peripheral blood mononuclear cells (PBMC) of one person convalescent from acute hepatitis B and one vaccinated individual. The former recognized a denaturation-insensitive epitope within the p24 protein whereas the latter recognized a denaturation-sensitive, conformational epitope located within the HBsAg common "a" determinant. This mAb, denominated ADRI-2F3, displayed a very high protective titer of over 43,000 IU/mg mAb and showed an extremely potent neutralizing activity in the in vitro model of HBV infection using primary hepatocytes from Tupaia belangeri as target. Recombinant variable heavy and light domain sequences derived from mAb ADRI-2F3 were cloned into eukaryotic expression vectors and showed identical fine specificity and 1 log10 higher titer than the original IgG1λ. It is envisaged that such mAb will be able to efficiently prevent HBV reinfection after liver transplantation for end-stage chronic HBV infection or infection after needle-stick exposure, providing an unlimited source of valuable protective anti-HBs antibody.

Show MeSH
Related in: MedlinePlus