Influenza virus nucleoprotein and matrix protein 1 T-cell epitopes (NP/M1 T-cell epitopes)

Influenza virus nucleoprotein (NP) and matrix protein 1 (M1) are highly conserved internal proteins essential for the viral lifecycle, including genome encapsidation, nuclear transport, and structural integrity (UniProt P03466; UniProt P03485). Unlike the surface glycoproteins hemagglutinin and neuraminidase, which undergo frequent antigenic drift, the sequences of NP and M1 remain relatively stable across various influenza A and B strains, including those with pandemic potential (Gras et al., 2010, Frontiers in Immunology). These proteins are processed by host cells into short peptides, or T-cell epitopes, which are presented on the cell surface by Major Histocompatibility Complex (MHC) molecules to activate CD4+ and CD8+ T-cells (Neefjes et al., 2011, Nature Reviews Immunology). Therapeutic strategies, such as universal influenza vaccines, aim to prime the immune system to recognize these conserved epitopes, facilitating the rapid clearance of infected cells regardless of the virus's surface subtype. Clinical-stage candidates like Multimeric-001 (M-001) and FLU-v utilize these conserved epitopes to induce broad-spectrum, cross-reactive cellular immunity (Atsmon et al., 2012, Vaccine; Pleguezuelos et al., 2020, Lancet Infectious Diseases). A primary challenge in targeting these epitopes is HLA restriction, as the specific MHC alleles of a patient determine which viral peptides can be effectively presented and recognized by the immune system.

Other names

Influenza NP and M1 epitopesMHC-presented influenza peptidesConserved influenza internal antigensUniversal influenza vaccine targetsNP/M1 MHC-peptide complexes

Induction of cross-reactive cellular immune responses, specifically CD4+ and CD8+ T-cell activation, against conserved internal viral antigens to provide broad protection across different influenza strains.