Generation, characterization, and protective ability of mouse monoclonal antibodies against the HA of A (H1N1) influenza virus

Abstract

Influenza virus infections pose a continuous threat to human health. Although vaccines function as a preventive and protective tool, they may not be effective due to antigen drift or an inaccurate prediction of epidemic strains. Monoclonal antibodies (mAbs) have attracted wide attention as a promising therapeutic method for influenza virus infections. In this study, three hemagglutinin (HA)-specific mAbs, named 2A1, 2H4, and 2G2, respectively, were derived from mice immunized with the HA protein from A/Michigan/45/2015(H1N1). The isolated mAbs all displayed hemagglutination inhibition activity and the 2G2 mAb exhibited the strongest neutralization effect. Two amino acid mutations (A198E and G173E), recognized in the process of selection of mAb-resistant mutants, were located in antigenic site Sb and Ca1, respectively. In prophylactic experiments, all three mAbs could achieve 100% protection in mice infected with a lethal dose of A/Michigan/45/2015(H1N1).A dose of 1 mg/kg for 2H4 and 2G2 was sufficient to achieve a full protective effect.Therapeutic experiments showed that all three mAbs could protect mice from death if they received the mAb administration at 6 h postinfection, and 2G2 was still protective after 24 h. Our findings indicate that these three mAbs may have potential prevention and treatment value in an H1N1 epidemic, as well as in the study of antigen epitope recognition.

Identification and analysis of B cell epitopes of hemagglutinin of H1N1 influenza virus

“…Therefore, the study of antigenic epitopes is of great significance for the detection and diagnosis of pathogenic microorganisms, the prediction of variation trend, the pathogenic mechanism and the design of epitope vaccine. So far, the main methods for epitope prediction include computer simulation technology and monoclonal antibody (mAb) technology (Devi et al 2021 ; Wang et al 2022 ).…”