Multiple epitope string (MES)

A multiple epitope string (MES) is a synthetic molecular construct designed for use in vaccines and immunotherapies, consisting of a series of immunodominant epitopes linked together in a single polypeptide chain (Source: PubMed PMID: 11544351). These epitopes are typically derived from various proteins of a single pathogen or from multiple different pathogens to provide broad-spectrum protection. The primary biological role of an MES is to serve as a concentrated source of antigens that are processed by the host's cellular machinery and presented on Major Histocompatibility Complex (MHC) molecules to trigger robust T-cell and B-cell responses (Source: Frontiers in Immunology, 2020). In clinical applications, MES constructs are often delivered via DNA plasmids or viral vectors, such as Modified Vaccinia Ankara (MVA), to combat complex diseases like malaria, HIV, and various cancers. A critical design challenge for MES involves the use of appropriate linkers to ensure efficient proteasomal processing and to prevent the creation of "junctional neoepitopes" that could divert the immune response away from the intended targets (Source: Vaccine, 2016). By focusing the immune system on specific, highly conserved regions of a pathogen, MES-based strategies aim to overcome the limitations of whole-organism vaccines, such as poor stability or the presence of immunosuppressive decoys. This approach allows for the inclusion of epitopes that bind to a wide variety of Human Leukocyte Antigen (HLA) alleles, potentially increasing the vaccine's efficacy across diverse human populations.

Other names

Multi-epitope stringPoly-epitope stringString-of-beads constructMulti-epitope vaccine

Induction of specific immune responses by presenting multiple immunodominant epitopes to T-cells and B-cells via MHC molecules.