Thyroglobulin peptide-Major Histocompatibility Complex (TG-pMHC)

The Thyroglobulin peptide-Major Histocompatibility Complex (TG-pMHC) is a molecular assembly consisting of a processed fragment of the thyroglobulin protein (UniProt: P01266) bound to the groove of an MHC molecule, typically MHC Class II such as HLA-DR (PMID: 15105305). This complex plays a pivotal role in the immune system's surveillance and is the primary driver of autoimmune thyroid diseases (AITD) such as Hashimoto's thyroiditis and Graves' disease (PMID: 30364014). In these conditions, the presentation of specific immunodominant thyroglobulin epitopes, such as TG2098 or TG2540, by antigen-presenting cells leads to the activation of autoreactive CD4+ T cells (PMID: 11169395). Therapeutic interventions targeting the TG-pMHC complex are currently focused on antigen-specific immunotherapies designed to restore peripheral tolerance. These approaches, including tolerogenic vaccines and peptide-loaded nanoparticles, aim to induce regulatory T cells or promote the exhaustion of pathogenic T cells specifically reactive to the thyroglobulin peptide. By targeting the specific pMHC complex rather than providing broad immunosuppression, these therapies seek to treat the underlying cause of thyroid autoimmunity while preserving overall immune function.

Other names

Thyroglobulin-derived peptide-MHC complexTG-HLA complexThyroglobulin epitope-MHC complexTG-MHC II complex

Induction of antigen-specific immune tolerance through the modulation of T-cell responses, including the induction of regulatory T cells (Tregs) or the deletion of autoreactive T-cell clones (PMID: 30364014).