Influenza A virus Matrix protein 2 ectodomain-Nucleoprotein fusion antigen (M2e-NP)

The Influenza A virus Matrix protein 2 ectodomain-Nucleoprotein (M2e-NP) fusion antigen is a recombinant protein construct developed as a candidate for universal influenza vaccines. It integrates the highly conserved 23-amino acid extracellular domain of the M2 ion channel (M2e) with the internal nucleoprotein (NP), both of which exhibit minimal antigenic variation across different influenza A subtypes (1.2.1, 1.2.2). M2e serves as a target for broadly reactive antibodies that facilitate the clearance of infected cells through antibody-dependent cellular cytotoxicity (ADCC) and phagocytosis (ADCP) (1.3.2, 1.4.5). NP is a potent inducer of cytotoxic T-lymphocyte (CTL) responses, providing a second layer of protection by recognizing and destroying infected cells via MHC-I presentation (1.3.3, 1.4.3). This dual-action approach aims to provide heterosubtypic immunity, potentially protecting against seasonal drift and pandemic shifts that evade traditional hemagglutinin-based vaccines (1.2.5, 1.4.2). Clinical evaluations of M2e-NP fusion proteins, such as the N8295 candidate, have demonstrated their ability to induce robust immune responses and reduce viral replication in challenge models (1.3.1).

Other names

M2e-NP fusion proteinM2e-NP chimeric proteinUniversal influenza vaccine antigen M2e-NPMatrix protein 2 ectodomain-NucleoproteinInfluenza A virus M2e-NP

Induction of cross-reactive humoral and cellular immunity; anti-M2e antibodies mediate ADCC and ADCP against infected cells, while NP-specific CD8+ T-cells eliminate infected cells via MHC-I recognition.