Patient-specific neoantigen peptide-MHC complexes (pMHC)

Patient-specific neoantigen peptide-MHC (pMHC) complexes are unique molecular targets formed when mutated proteins in cancer cells are processed into short peptides and presented on the cell surface by Major Histocompatibility Complex (MHC) molecules [1.2.1]. Unlike tumor-associated antigens, these neoantigens are absent from normal tissues, making them highly specific targets that bypass central immune tolerance [1.4.1]. They play a critical role in the cancer-immunity cycle by serving as the primary recognition signal for cytotoxic T-cell receptors (TCRs) [1.2.2]. Therapeutic strategies targeting these complexes include personalized mRNA or peptide vaccines designed to prime the immune system, and adoptive cell therapies like TCR-engineered T cells (TCR-T) that provide a direct effector response [1.1.4, 1.2.4]. Additionally, novel bispecific antibodies and T-cell engagers are being developed to bridge immune cells directly to these specific pMHC targets, offering a potent and personalized approach to oncology [1.1.1, 1.2.3]. These therapies aim to overcome the limitations of traditional treatments by providing a highly specific, durable, and patient-tailored immune response against the tumor [1.3.1, 1.3.2].

Other names

Tumor-specific neoantigen-MHC complexesNeoantigen-HLA complexesMutant peptide-MHC complexesTSA-MHC complexesPersonalized neoantigen-MHC complexes

Personalized neoantigen-targeting therapies work by enhancing the immune system's ability to recognize and destroy tumor cells presenting unique mutant peptides. Vaccines (mRNA or peptide-based) deliver the genetic code or physical fragments of these neoantigens to antigen-presenting cells, which then present them to T cells, inducing a de novo or expanded population of neoantigen-specific CD8+ and CD4+ T cells [1.2.1, 1.4.1]. Adoptive cell therapies, such as TCR-T, involve re-infusing a patient's own T cells that have been genetically engineered to express a high-affinity TCR specific for a particular neoantigen-MHC complex [1.2.2]. Bispecific antibodies or T-cell engagers (BiTEs) facilitate a physical bridge between the T cell and the tumor-specific pMHC, bypassing the need for natural TCR-MHC interaction to trigger cytotoxic activity [1.1.1, 1.2.3].