Monoclonal antibody against VP0 recognizes a broad range of human parechoviruses

Area of Science:

• Virology
• Immunology
• Molecular Biology

Background:

• Parechoviruses (PeVs) are significant human pathogens, particularly in infants, causing a spectrum of illnesses from mild gastrointestinal or respiratory symptoms to severe central nervous system infections.
• Accurate and rapid diagnosis of PeV infections is crucial for effective patient management and public health, necessitating the development of high-quality diagnostic tools.

Purpose of the Study:

• To develop and characterize monoclonal antibodies with broad specificity against parechoviruses for improved diagnostic applications.
• To identify a functional antigen for generating pan-parechovirus antibodies.

Main Methods:

• Cloning of VP4 and VP2 genes from human parechovirus A1 (PeV-A1) and production of VP0 fusion protein.
• Development and isolation of monoclonal antibodies, with detailed characterization of one IgG1/κ antibody (Mab-PAR-1) using western blot and immunofluorescence assays.
• Epitope mapping using a peptide library screen to identify the antibody's binding site.

Main Results:

• Isolation of two pan-parechovirus antibodies (IgG and IgM).
• Mab-PAR-1 demonstrated broad reactivity against nineteen PeV-A1 isolates and five other parechovirus types (2-6) without cross-reactivity to common enteroviruses and rhinoviruses.
• Identification of a unique epitope for Mab-PAR-1 located at the junction of VP0, VP1, and VP3 capsid proteins.

Conclusions:

• The PeV-A1-VP0 fusion protein serves as an effective antigen for developing broadly reactive monoclonal antibodies against parechoviruses.
• The characterized monoclonal antibody, Mab-PAR-1, holds significant potential for the development of sensitive and specific diagnostic assays for a wide range of parechovirus infections.