Identification of a linear B-cell epitope in B117L-213 protein of ASFV using monoclonal antibodies.

African Swine Fever (ASF) is a highly infectious, acute, hemorrhagic Swine disease caused by the African Swine Fever Virus (ASFV). It is lethal to both domestic pigs and wild boars, and has caused significant economic losses to the global pig industry. Vaccines represent the most significant means of preventing and treating viral diseases. However, due to the complex genome and strong immune evasion mechanism of ASFV, there has been no successful development of a vaccine that has been made commercially available on a global scale. Thus, the focus of present research efforts is the study of its viral protein. B117L is a non-structural protein encoded by the ASFV, the function of which has not yet been fully defined. It belongs to a variable region in the viral genome. Direct studies on the B117L protein are relatively scarce, but analogous proteins (MGF360/505 family) have been found to have immunoregulatory functions. B117L may be a potential immunoregulatory protein of ASFV involved in viral immune evasion, replication regulation, or pathogenesis, but further investigation is required to determine its specific function. The amino acid sequence of African swine fever B117L protein is as follows: MGYTIQLDGDYCWDEDPTHHDPYMQANATSHVATSYATTSHAATPHAAAHHTFHEPFIKLNLTDKNIFNGLGFILIVIFIYLLLITLQQMLTRHIYNTVQHCVKAHLDSKNLQ. In order to facilitate a more effective expression of the B117L protein, the hydrophobic side B117L - 213 in amino acid protein is utilized, and its amino acid sequence is MGYTIQLDKDGDYCWDEDPTHHDPYMQANATSHVATSYATTSHAATPHAAAHHTFHEPFIKLNLTDKNIFN. The preparation of B117L-213 monoclonal antibody has the potential to facilitate further understanding of the B117L protein, the development of an ASFV vaccine, and the control of ASFV epidemics. The study encompassed of three strains of ASFV B117L-213 protein-specific monoclonal antibodies: 7F8D2A6, 8B11C8F9 and 8H1D5H8 (IgG2b/Kappa subtypes). The findings of this study are of considerable significance for the design and development of ASFV vaccines, and also provide relevant information for the study of the function of the B117L protein.