IDH1 R132H peptide–major histocompatibility complex class II complex (IDH1 R132H pMHC-II complex)

The **IDH1 R132H peptide–major histocompatibility complex class II complex** refers to a molecular complex in which a peptide derived from the IDH1 protein carrying the R132H mutation is presented on the cell surface by MHC class II molecules. This neoantigen complex plays a central role in the immune recognition of tumor cells harboring the IDH1 R132H mutation, most commonly found in low-grade gliomas and other cancers. Peptides containing the R132H mutation are processed intracellularly and loaded onto MHC II molecules, which then present them to CD4+ T helper cells. This presentation can trigger a specific anti-tumor immune response, and the complex is the molecular basis for peptide vaccine therapies targeting IDH1 R132H mutant tumors. The immunogenicity, specificity, and safety of this approach are supported by early-phase clinical data using the NOA-16 vaccine, with patients demonstrating mutation-specific T cell and antibody responses[1][2][6]. Monitoring of D-2-hydroxyglutarate (D-2-HG) can serve as a biomarker for IDH1 mutant activity, and the presence of IDH1 R132H peptide–MHC II complexes can aid patient selection for immunotherapy. The peptide-MHC complex itself is not a “receptor,” but is a validated immunotherapy target and a tool for immune monitoring[1][2][6].

Other names

IDH1 R132H–MHC complexIDH1 R132H neoantigen–MHC complexMutant IDH1 R132H peptide–MHC class II complex

Presentation of IDH1 R132H mutant peptide by MHC class II molecules to CD4+ T cells, inducing mutation-specific T cell responses and antitumor immunity Stimulation of helper T cell responses, promoting broader adaptive anti-tumor immunity Induction of antibody responses against the mutant peptide