Patient-specific tumor neoantigen peptide–MHC class II complex (NeoAg-MHC II complex)

Patient-specific tumor neoantigen peptide–MHC class II complexes are personalized molecular targets formed by the presentation of unique, mutation-derived peptides on Major Histocompatibility Complex (MHC) class II molecules (Sahin & Türeci, 2018; Xie et al., 2023). These complexes are primarily found on the surface of professional antigen-presenting cells (APCs) and occasionally on tumor cells, where they are recognized by the T-cell receptors (TCRs) of CD4+ helper T cells (Alspach et al., 2019). This recognition is a critical step in the cancer-immunity cycle, as CD4+ T cells provide essential help for the activation and memory formation of CD8+ cytotoxic T cells and can also exert direct anti-tumor effects (Alspach et al., 2019; Ott et al., 2017). Because these neoantigens arise from somatic mutations unique to an individual's tumor, they are absent from healthy tissue, making them ideal targets for highly specific immunotherapy with minimal off-target toxicity (Sahin & Türeci, 2018; Xie et al., 2023). Therapeutic strategies targeting these complexes include personalized mRNA, DNA, or peptide-based vaccines and TCR-engineered T-cell therapies, which aim to amplify the patient's endogenous immune response against their specific cancer profile (Xie et al., 2023; Ott et al., 2017).

Other names

Tumor neoantigen-HLA class II complexNeoepitope-MHC II complexPersonalized neoantigen-MHC II complexTumor-specific neoantigen-MHC II complex

Activation of CD4+ T-helper cells through the recognition of personalized neoantigen peptides presented on MHC class II molecules by T-cell receptors (TCRs), which coordinates a broader anti-tumor immune response (Sahin & Türeci, 2018; Alspach et al., 2019).