Major histocompatibility complex class I presenting SARS-CoV-2 peptides on artificial antigen-presenting cells (MHC I-SARS-CoV-2-aAPC)

The MHC class I presenting SARS-CoV-2 peptides on artificial antigen-presenting cells (aAPCs) is a synthetic immunological complex designed to mimic natural antigen presentation to stimulate a robust cellular immune response (NexImmune, 2021). This system utilizes nanoparticles or beads (aAPCs) conjugated with HLA-peptide complexes, where the peptides are derived from various SARS-CoV-2 proteins such as Spike, Nucleocapsid, and Membrane proteins (Oelke et al., 2014). By presenting these viral epitopes in the context of MHC class I molecules along with co-stimulatory signals, the aAPCs specifically target and expand CD8+ cytotoxic T lymphocytes (CTLs) capable of recognizing and destroying virus-infected cells (Schütz et al., 2022). This approach is particularly relevant for developing "off-the-shelf" T-cell therapies or vaccines that provide long-term immunity, especially in immunocompromised patients who may not respond well to traditional antibody-inducing vaccines (ClinicalTrials.gov, 2021). The therapeutic focus is on enhancing the T-cell arm of the immune system to provide protection against multiple viral variants by targeting conserved epitopes (PubMed, 2021). The aAPC platform allows for the precise control of the immune signal, potentially reducing the risk of systemic side effects compared to traditional systemic immune stimulants. Clinical development of this target complex, such as in the NEXI-004 program, aims to address the need for durable immunity in the face of evolving viral strains.

Other names

aAPC-MHC-peptide complexNEXI-004Artificial antigen-presenting cells for COVID-19HLA-peptide-aAPC complexSARS-CoV-2 antigen-presenting nanoparticles

Direct activation and expansion of antigen-specific CD8+ T cells through the engagement of T-cell receptors (TCRs) by MHC-peptide complexes and the provision of co-stimulatory signals.