Outer membrane vesicle lipopolysaccharide – mouse cathelin-related antimicrobial peptide-tagged spike fusion protein interface (OMV LPS–mCRAMP-Spike interface)

The Outer membrane vesicle lipopolysaccharide – mouse cathelin-related antimicrobial peptide-tagged spike fusion protein interface is a molecular assembly used in the development of "plug-and-display" nanovaccines (Wang et al., 2022, Nature Communications). This interface is formed by the non-covalent, high-affinity binding between Lipopolysaccharide (LPS) on the surface of bacterial Outer Membrane Vesicles (OMVs) and the mouse Cathelin-Related Antimicrobial Peptide (mCRAMP) fused to a target antigen, such as the SARS-CoV-2 Spike protein receptor-binding domain (RBD). The interaction is primarily driven by electrostatic attraction between the positively charged mCRAMP and negatively charged LPS, supplemented by hydrophobic interactions (Wang et al., 2022). This platform allows for the rapid decoration of OMVs with viral antigens, leveraging the OMV's natural role as an immunological adjuvant to enhance the host's immune response (Gao et al., 2022, Advanced Materials). By presenting the Spike protein in a highly repetitive and oriented manner, the interface facilitates the induction of potent neutralizing antibodies and cellular immunity against viral infections. While promising for rapid vaccine deployment, the primary clinical challenge associated with this interface is the inherent endotoxicity of LPS, which necessitates the use of genetically engineered bacterial strains to produce safe, detoxified OMVs (National Institutes of Health).

Other names

LPS-mCRAMP-RBD interfacePlug-and-display OMV vaccine platformmCRAMP-tagged Spike-OMV complexOMV-mCRAMP-RBD nanovaccine interface

The interface facilitates the stable anchoring of viral antigens onto bacterial outer membrane vesicles (OMVs) via high-affinity binding between mCRAMP and LPS, creating a potent immunogenic complex that activates TLR4 and presents antigens to B and T cells (Wang et al., 2022).