Pancreatic autoantigen-derived peptide–major histocompatibility complex (pMHC)

The pancreatic autoantigen-derived peptide–major histocompatibility complex (pMHC) is a molecular assembly consisting of a fragment of a pancreatic protein—such as insulin, glutamic acid decarboxylase 65 (GAD65), or zinc transporter 8 (ZnT8)—presented on the surface of antigen-presenting cells or beta cells within the grooves of MHC class I or II molecules (Roep & Peakman, 2012). In the context of Type 1 Diabetes (T1D), these complexes serve as the primary signal for the activation and recruitment of autoreactive T cells, which mistakenly identify beta cells as foreign and initiate their destruction (Di Lorenzo et al., 2007). Therapeutic strategies targeting these specific pMHC complexes aim to restore immune tolerance without causing systemic immunosuppression. Approaches include the use of pMHC-coated nanoparticles (Navacims) to induce regulatory T cells or peptide-based vaccines designed to desensitize the immune system (Santamaria, 2020). By focusing on the specific pMHC involved in the pathogenic process, these treatments seek to preserve remaining beta-cell function and halt the progression of T1D (Herold et al., 2019). This target represents a high-precision approach to treating autoimmune diseases by addressing the root cause of the immune attack.

Other names

Islet autoantigen-MHC complexInsulin peptide-MHC complexGAD65 peptide-MHC complexProinsulin peptide-HLA complexIslet-specific pMHC

Induction of antigen-specific immune tolerance through the expansion of regulatory T cells (Tregs) and the exhaustion or deletion of autoreactive T cells (Santamaria, 2020).