Novel Linear B Cell Epitopes of ASFV p54: Screening and Fine-Scale Mapping

Area of Science:

• Veterinary Virology
• Immunology
• Molecular Biology

Background:

• African swine fever (ASF) is a severe, fatal pig disease caused by the African swine fever virus (ASFV).
• Effective vaccines and rapid diagnostic methods are crucial for controlling ASFV outbreaks.
• The ASFV p54 protein is a significant target for diagnostic and vaccine development.

Purpose of the Study:

• To construct, express, and purify the ASFV p54 protein.
• To generate monoclonal antibodies (mAbs) against the p54 protein.
• To identify and characterize the B cell epitopes on the p54 protein for diagnostic and therapeutic applications.

Main Methods:

• Recombinant expression and purification of ASFV p54 protein.
• Generation of three monoclonal antibodies (mAbs): 9A3, 5H2, and 2G6.
• Epitope mapping using alanine scanning mutagenesis to identify linear epitopes and critical residues.

Main Results:

• Three mAbs (9A3, 5H2, 2G6) were successfully generated against ASFV p54 protein.
• Identified two minimal linear epitopes: ⁵⁶KKKAAAI⁶² (recognized by 9A3 and 5H2) and ¹⁰⁸TNRPATN¹¹⁴ (recognized by 2G6).
• ⁵⁶KKKAAAI⁶² represents a newly discovered linear epitope, conserved across ASFV genotypes I and II. Critical residues for antibody recognition were pinpointed.

Conclusions:

• The identified mAbs and epitopes provide a foundation for developing novel ASF diagnostic tools.
• These findings support the development of ASFV vaccines targeting B cell epitopes.
• The study offers theoretical backing for creating ASFV therapeutic antibody drugs.