DEVELOPMENT OF A POTENT MONOCLONAL ANTIBODY FOR TREATMENT OF HUMAN METAPNEUMOVIRUS INFECTIONS

Area of Science:

• Virology
• Immunology
• Structural Biology

Background:

• Human metapneumovirus (HMPV) causes significant respiratory illness, with limited therapeutic options available.
• Monoclonal antibodies (mAbs) are being explored as potential treatments and preventatives for HMPV infections.

Purpose of the Study:

• To discover and characterize a novel monoclonal antibody (mAb) with broad neutralizing activity against HMPV.
• To elucidate the binding mechanism and efficacy of the identified mAb, named 4F11.

Main Methods:

• Cryo-electron microscopy was used to determine the binding structure of 4F11 to the HMPV prefusion F protein.
• In vitro neutralization assays were performed across diverse HMPV strains.
• In vivo efficacy was assessed using a hamster challenge model.

Main Results:

• 4F11 binds to a unique epitope (site Ø) on the HMPV F protein with a distinct glycan-dependent mechanism.
• The mAb demonstrated potent and broad in vitro neutralization of various HMPV strains with low resistance development.
• 4F11 significantly reduced viral loads in hamsters challenged with HMPV.

Conclusions:

• 4F11 is a potent, broadly neutralizing mAb against HMPV with a unique binding mode.
• Its demonstrated in vitro and in vivo efficacy makes it a promising therapeutic candidate for HMPV, especially for high-risk groups.