Immunization with GP1 but Not Core-like Particles Displaying Isolated Receptor-Binding Epitopes Elicits...

Area of Science:

• Virology
• Immunology
• Vaccine Development

Background:

• New World arenaviruses, including Junín virus (JUNV), cause severe human diseases like Argentine hemorrhagic fever.
• Current treatment relies on convalescent plasma, but supplies are limited, necessitating alternative antibody-based therapies.
• Rodent reservoir hosts complicate disease control, highlighting the need for effective therapeutic strategies.

Purpose of the Study:

• To induce a neutralizing antibody response against the Junín virus glycoprotein subunit 1 (GP1) in rabbits.
• To evaluate the immunogenicity of specific peptide sequences within GP1 involved in cellular receptor interactions.
• To explore GP1 as a potential target for developing novel immunotherapeutics against JUNV.

Main Methods:

• Rabbits were immunized with specific peptide sequences from JUNV GP1 presented as part of hepatitis B virus core-like particles.
• Recombinant JUNV GP1, purified from mammalian cells, was used to immunize rabbits.
• Virus neutralization assays were performed to assess the antibody response against various JUNV strains.

Main Results:

• Particulate antigen-presented peptides did not efficiently induce neutralizing antibodies.
• Recombinant JUNV GP1 elicited high titers of virus-neutralizing antibodies in rabbits.
• The induced antibodies demonstrated cross-neutralization against multiple unrelated JUNV strains.

Conclusions:

• Junín virus GP1 alone is capable of inducing a potent neutralizing antibody response.
• Epitope presentation is critical for effective antibody induction against JUNV.
• Rabbit antibodies effectively neutralize JUNV, supporting their use in developing humanized monoclonal antibody immunotherapeutics.